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1. Field of the Invention
The present invention relates to processes for producing coke, an artificial graphite having a high graphitization degree, a carbon material for a negative electrode of non-aqueous solvent type secondary battery having a high discharge capacity and a high charge-discharge efficiency, from mesophase pitch (optically anisotropic pitch), and a pitch composition mainly used for the production of these substances.
2. Description of the Prior Art
Mesophase pitch is an excellent carbon material capable of producing pitch coke having a high graphitizability at a high yield. However, when the mesophase pitch is held in an electric furnace and heat-treated therein, gases are generated therefrom, so that the pitch is foamed and the volume thereof increases several tens times. Thus, the production of coke from the mesophase pitch has a problem concerning its productivity. Also, in the case where the mesophase pitch is used as a binder to produce a carbon-based molding material, the pitch is foamed by gases generated. As a result, there arises such a problem that coke derived from the mesophase pitch which is contained in the carbon-based molding material exhibits a low density.
Japanese Patent Application Laid-open No. Heisei 6(1994)-299076 discloses a method of adding carbon black to mesophase pitch in order to inhibit the foaming of the mesophase pitch.
However, the coke produced by the above method of adding carbon black to mesophase pitch, shows a poor graphitizability due to strong interaction between carbon black and mesophase pitch, thereby failing to obtain an artificial graphite having a high graphitization degree. Therefore, it has been required to provide not only a process for producing high-density coke at a high productivity while avoiding foaming of the mesophase pitch, but also a process for producing an artificial graphite having a high graphitization degree.
In addition, recently, lithium ion secondary batteries having a negative electrode made of a carbon material, have been rapidly put into practice as a power source for various electronic devices used in the current high information-oriented society, because these batteries show a high voltage and a high-energy density and are excellent in safety and cycle characteristics.
Natural graphite conventionally used exhibits a high discharge capacity due to its higher crystallinity as compared to those of other carbon materials. However, it is required that the natural graphite is pulverized in order to prepare a negative electrode material therefrom. Therefore, the pulverized natural graphite has a large surface area, which results in low charge-discharge efficiency at initial cycle. In addition, the natural graphite is deteriorated in cycle life since it contains a large amount of impurities such as metal components.
Accordingly, it has also been required to provide carbon materials containing a less amount of impurities such as metal components and exhibiting a high charge-discharge efficiency at initial cycle. As carbon materials satisfying such a requirement, Japanese Patent Application Laid-open No. Heisei 10(1998)-121054 discloses a graphite powder containing a less amount of impurities and exhibiting a crystallinity compatible to that of natural graphite, which is produced by heat-treating specific mesophase pitch in a specific temperature range in a non-oxidative atmosphere, and then successively subjecting the heat-treated material to pulverization and graphitization.
However, the graphite powder obtained in Japanese Patent Application Laid-open No. Heisei 10(1998)-121054 has a highly-oriented flow structure. Therefore, when such a graphite powder is used as an electrode material for secondary batteries, there is caused such a problem that the solvent contained in an electrolyte solution shows a high decomposition activity upon charging due to the crystal structure on the surface of the graphite powder, which results in deteriorated charge-discharge efficiency of the batteries. Further, as described above, the mesophase pitch is undesirably foamed by gases generated when heat-treated in an electric furnace, so that the volume thereof increases up to several tens times, thereby causing the problem concerning its productivity. Accordingly, it has been demanded to provide a process for producing a graphite powder capable of realizing not only a high productivity but also a high discharge capacity and a high charge-discharge efficiency of finally produced batteries. | {
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The present invention is directed to methods and apparatus for joining multilayer joints of pipe. Dual layer and multilayer pipe joints are typically used in specialty pipeline systems, where pipeline repair or replacement is costly and corrosive elements or abrasive pipeline fluids substantially decrease the useful life of typical metal pipes. For instance, dual and multilayer pipelines are typically installed in subsea operations and in pipelines intended for transportation of corrosive or abrasive materials.
Although various barrier systems and reverse current techniques have been used to extend the life of the metal pipelines, pipelines having an inner material in contact with the fluid have been most widely accepted in the industry. Moreover, pipelines formed from only plastic materials have not been widely accepted in large pipeline systems because of poor stress characteristics. On the other hand, piping systems constructed of both metal and plastic layers have been widely accepted within the process piping industry.
A dual layer pipe typically comprises an outer casing which provides bending, tensile and radial strength to the pipe, and an inner plastic or rubber liner which serves as a smooth noncorrosive flow surface. Trilayer pipe typically utilizes a similar outer steel casing and an inner plastic pipe, but an annulus is provided between these layers which is typically filled with a cement grout or other inert material. Pipe with more than three distinct structural layers is also possible, although less common. For the purposes of the present invention, multilayer pipe is defined as pipe with three or more distinct structural layers.
A multilayer pipeline has the same benefit as a dual layer pipeline, but offers additional protection to withstand higher degrees of pressure, shock, impact and cyclic loading. Also, dual layer pipe may be suited for process piping applications, but is not suitable for many pipeline installations (e.g., subterranean applications). Multilayer pipe, on the other hand, is well suited for both process piping applications and pipeline applications. The cement grout provides a convenient means of joining together the outer steel casing and the inner plastic pipe. Further, the cement grout layer enables the multilayer pipeline to better withstand corrosion deterioration of the metal casing, serves as an added barrier between the metal layer and plastic layer to inhibit corrosion of the steel pipe if the plastic pipe were to leak (thereby extending the effective life of a pipeline handling corrosive fluids), serves as an insulator to reduce temperature variations in the transported fluids, and provides a means for regulating the pipeline buoyancy by varying the density of the cement grout mixture.
Corrosion resistant pipe may be formed by painting or coating the interior of a metal pipe. Dual layer pipe, on the other hand, is generally defined as pipe having two layers of distinct structural strength, and may be formed by extruding steel over plastic pipe, by contracting plastic pipe and subsequently expanding the plastic pipe to the interior of a metal pipe, or by wrapping steel bands over plastic pipe. Although dual layer pipe has been used commercially for years, it does not offer the substantial benefits of a multilayer pipe, and is seldom used in the pipeline field. Moreover, industrial acceptance of dual layer pipelines has been limited, in part, because the methods and apparatus for joining dual layer pipe sections have been time consuming and have often not resulted in leakproof seals between the plastic and metal layers of a pipe, especially at higher pressures.
Various types of joints for joining sections of pipe are depicted and described by Robert H. Perry and Cecil H. Chilton in Chemical Engineers' Handbook, Title Edition, commencing at page 6-57. Non-metallic pipe and lined pipe systems, and joints typically used in these systems, are subsequently described at page 6-79. Pipeline joints are also depicted in U.S. Pat. Nos. 3,827,733; 3,986,731; 4,011,652; 4,053,247; and 4,060,263. Yet, none of these joints have proven to be satisfactory in many situations, either because of pressure or expense.
Threaded pipeline joints are not generally accepted because they do not provide a continuous integral wall, and are therefore prohibited in many underground pipeline applications. Threaded joints also provide stress and corrosion concentration points, and do not lend themselves well to dual or multilayer pipe joints. Other joints do not adequately seal the plastic liner and allow corrosive fluid to come in contact with the metal outer casing. Dow Chemical Corporation and Peabody Corporation supply a dual layer plastic lined pipe, but the sections are flanged with molded raised face ends, or with ends suitable for gasketed pipe joints. These pipe sections are thus expensive and time consuming to install. Moreover, special precautions must be taken to insure that no welding operations are done on the pipe or flange components, since excessive heat can cause liner decomposition and failure.
For barrier corrosion control, as in coated pipe, a bell and sleeve joint supplied by AMF Tuboscope is also commercially available for joining pipe sections. This technique, however, requires that each end of pipe section be flared outwardly or belled to allow insertion of a joining sleeve, which substantially increases the cost of the pipe sections. A thin sleeve with an epoxy coating is provided for joining the sections of the pipe, but care must be taken so that the weld does not contact the sleeve when the pipe sections are joined or the epoxy coating may be severely damaged.
The above-described joints do not efficiently and reliably function to join sections of dual layer pipe, and these above-described joints therefore limit the acceptance of dual layer pipeline systems. Moveover none of the above-described joints may be satisfactorily employed to join sections of a steel-cement-plastic layer pipe, as described above. Although multilayer pipe is widely recognized as obtaining the same benefits as dual layer pipe plus significant additional features, the absence of an efficient and reliable multilayer pipe joint limits the industrial use and acceptance of standardized joints of multilayer pipe.
U.S. Pat. No. 3,662,045 describes a method for providing a multilayer pipeline which had proven satisfactory in many applications. The technique described in this patent, however, is particularly suitable for repairing a conventional metallic pipeline by inserting a smaller diameter plastic pipe within the line and subsequently filling the annulus with a cement grout. More particularly, the annulus of the multilayer pipeline described in this patent is filled with cement once the metallic line and inner plastic pipe are in place. This technique does not utilize a prefabricated joint for joining multilayer pipe sections, but rather forms a multilayer pipe in the field and uses flanged or welded joints spaced thousands of feet apart to join sections of pipe, wherein the joint is also formed at the installation site by filling the annulus portion with the cement grout. Thus, the technique described in this patent is not adaptable for forming convenient lengths of multilayer pipe at a plant location and transporting multilayer pipe sections to required installation sites.
The present invention overcomes these problems by providing a multilayer pipe joint which can be easily, effectively and reliably utilized to join prefabricated sections of multilayer pipe at the installation site. This enables convenient length (e.g. 40 foot) of multilayer pipe to be completely formed at a manufacturing plant with a cement grout in place, and the pipe sections may then be joined at the installation site without the need for time consuming cement pumping procedures.
The disadvantages of the prior art are thus overcome with the present invention, and novel methods and apparatus are hereinafter described for efficiently and reliably joining together sections of a multilayer pipeline. | {
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Prediction and control of residence time of an object or particle in a reactor, heat exchanger or holding tube is important for many continuous flow processing operations. One example of a continuous flow processing operation is aseptic processing of liquid based foods, such as potato soup. Usually, liquid based foods include liquid particles, large solid particles and smaller solid particles. The prediction and control a particle""s residence time assures the correct processing time for the particle. The residence time of large solid particles is especially important during the aseptic processing of foods with large solid particles. Continuous flow operations usually involve a flow confined by at least one wall. Hence, the flow of particles may be slower near the wall than away from the wall. In fact in a tube with laminar flow, the outside portion of the flow is usually much slower than the center portion of the flow. This creates a situation where individual particles of the flow can be under-processed or over-processed, due to the different residence times.
Conventional continuous flow reactors, heat exchangers, and holding tubes have relatively wide distributions of residence times for individual particles of the flow. The individual particles can have much longer or shorter processing time than the average processing time of all the particles. A wide distribution of residence times means some particles are processed for much shorter times, while other particles are processed for much longer times. To compensate, often the processing time is increased to insure that the fastest moving particles receive the minimum allowable processing. Whereby, the tradeoff is that the slowest moving particles are over-processed. Depending on the application, this can translate to inferior quality product, increased energy usage and reduced throughput.
Several approaches have been used to resolve the problems associated with the wide distribution of residence times in continuous processing. A first approach is the use of empirical data or mathematical models to determine the distribution of residence times for a particular set of flow conditions of individual particles. Once the distribution is determined, the processing time can be adjusted appropriately. The problem is that accurately modeling the residence time is a complex process because of the interaction of numerous factors. Likewise, the collection of empirical data is difficult because seemingly insignificant, uncontrolled differences in flow conditions can result in important changes of residence time distribution. A second approach is to control flow parameters such as laminar or turbulent flow, tube diameter, tube length, or flow path to create the desired distribution of residence times. The control of flow parameters to achieve the desired distribution of residence times is problematic for the same reasons as the first approach. Furthermore, even if residence time can be accurately predicted or measured, the fact remains that the distribution is often wider than desired and flow parameter control is often inadequate to achieve a narrow distribution of residence times. A third approach is to use batch processing rather than continuous processing. Batch processing can easily provide a narrow distribution of residence times and is often the best solution. The problems with batch processing is that it creates materials handling problems, scheduling problems and is more expensive. A final approach is the development of mechanisms that physically control residence time. Current applications of this approach are not without disadvantages. Some are difficult to implement, some damage particles of the flow, while others do not always provide a uniform control of residence time. Furthermore, they do not specifically control residence time of liquid particles apart from solid particles in the flow. This leads to the over-processing of some of the particles in the flow, thereby resulting in a reduction in product quality.
It is an object of the present invention to provide a system for the uniform processing of a flow of particles.
It is an object of the present invention to provide the control of residence time of individual particles in a continuous flow processing operation.
It is an object of the present invention to provide system to prevent the necessity of over-processing foods to meet safety requirements in a continuous flow processing operation.
The present invention provides a segmented flow device for controlling the residence time of particles in a flow. The device includes a processing conduit having an inlet end and an outlet end. A feed port is at the inlet end for inserting the flow to be processed. A release port is at the outlet end for removing the flow after processing. The device includes a series of barriers moving through the processing conduit to segment the flow during processing to allow control of residence time of the particles of the flow. A continuation section provides a path between the inlet and outlet ends of the processing conduit for receiving the barriers from the outlet end and returning the barriers to the inlet end. A first input in the device is for providing an inlet pressure to the inlet end and a second input for providing an outlet pressure to the outlet end, such that the inlet and outlet pressures are also used for controlling the flow. | {
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Conventionally, an administrator performs administrative functions (i.e., network updates, maintenance, etc.) by establishing connections to one agent at a time to perform such functions. The communication session setup and teardown process across a data network may be used to establish a connection with a single agent to perform the administrative functions, such as execute commands remotely from an administrative client interface. It would be optimal to establish a single client session by the administrator and execute commands simultaneously with multiple agents from the single client session. | {
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It is known that, in image pickup elements, such as CCD sensors and CMOS sensors, a localized sensitivity failure of a semiconductor may occur during a manufacturing process or after the manufacturing process. When such a sensitivity failure occurs, an electric charge output in accordance with an incident light quantity cannot be obtained from a pixel, as a result of which a white spot or a black spot that is unrelated to an object appears on an image pickup screen. Such a pixel that causes a white spot or a black spot unrelated to an object to be output is called a defective pixel. In order to correct image quality degradation caused by such a defective pixel by signal processing, the defective pixel is detected beforehand. First, when manufacturing an image pickup element at a semiconductor factory, any defective pixel in the manufactured image pickup element is detected, and position data of the detected defective pixel is stored in a nonvolatile memory.
Even after installing the image pickup element in an image pickup apparatus, any defective pixel in the image pickup element can be detected. For example, when a mechanical shutter of the image pickup apparatus is in a light-shielding state, a pixel (white-spot defective pixel) whose output level from the image pickup element exceeds a predetermined level is detected. Alternatively, when the shutter is opened, and the incident light quantity is set to a predetermined quantity, any pixel (black-spot defective pixel) at which an output level does not reach the predetermined level is detected. Position data of the detected white-spot defective pixel or the detected black-spot defective pixel is stored in the nonvolatile memory. Because position data of the above-described defective pixels can be stored prior to normal image pickup operation (prior to the imaging apparatus being used for actual imaging of an object), these defective pixels can be referred to as “steady defective pixels”. During normal image pickup operation of the image pickup apparatus, an image signal obtained by imaging an object is corrected with signal processing by taking into account the defective pixels on the basis of the pre-stored position data.
In recent years, the probability with which defective pixels occurs tends to increase due to an increase in the number of pixels of image pickup elements. Further, formation of finer pixels resulting from the increase in the number of pixels of the image pickup elements has caused the recognition of new phenomena that have been hitherto overlooked. For instance, the existence of pixels whose signal levels are read increase or decrease considerably when pixel signals from the image pickup elements are repeatedly read out. Pixels that cause such a phenomena to occur are called blinking defective pixels. There are blinking defective pixels that depend upon temperature and storage time, and blinking defective pixels that do not depend upon temperature and storage time. Blinking defective pixels are variously mechanically generated.
Blinking defective pixels are normal pixels at certain times, and are white-spot defective pixels at other times, so that they act as though they are blinking white-spot defective pixels. Therefore, when a manufacturing process of an image pickup element is performed or when an image pickup apparatus performs a self-measurement operation, all of the blinking defective pixels cannot be detected by detecting each defective pixel once. In addition, the defective pixels are turned on during an actual image taking operation in which an image of a taken object is recorded, as a result of which the blinking defective pixels stand out, thereby degrading the taken image.
In view of such a situation, Japanese Patent Laid-Open No. 2003-37781 discloses a technology in which, on the basis of a plurality of image signals obtained under the same condition, defective pixel addresses of an image pickup element are detected, and the pixel addresses where the number of times by which defects are determined is greater than a predetermined number of times are detected as final defective pixel addresses. | {
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The heart is the center of a person's circulatory system. It includes an electro-mechanical system performing two major pumping functions. The left portions of the heart draw oxygenated blood from the lungs and pump it to the organs of the body to provide the organs with their metabolic needs for oxygen. The right portions of the heart draw deoxygenated blood from the organs and pump it into the lungs where the blood gets oxygenated. The body's metabolic need for oxygen increases with the body's physical activity level. The pumping functions are accomplished by contractions of the myocardium (heart muscles). In a normal heart, the sinoatrial node, the heart's natural pacemaker, generates electrical impulses, known as action potentials, that propagate through an electrical conduction system to various regions of the heart to excite myocardial tissues in these regions. Coordinated delays in the propagations of the action potentials in a normal electrical conduction system cause the various regions of the heart to contract in synchrony such that the pumping functions are performed efficiently.
A blocked or otherwise damaged electrical conduction system causes the myocardium to contract at a rhythm that is too slow, too fast, and/or irregular. Such an abnormal rhythm is generally known as arrhythmia. Arrhythmia reduces the heart's pumping efficiency and hence, diminishes the blood flow to the body. One type of arrhythmia is fibrillation, where the heart quivers instead of beating normally. For instance, atrial fibrillation (AF) is associated with an abnormal heart rhythm where the atria quivers. AF as a disease target represents a significant unmet need with a hospitalization growth rate of 16.7% over last 5 years. AF-related hospitalization charges contribute over $3 B annually to health care system expenditures. Treatments for arrhythmias include electrical therapy such as pacing and defibrillation therapies, ablation and drug therapies. Catheter based therapies for AF are destructive, dangerous, and highly variable. For example, the procedure takes on the average about 4 hours, and has at best 50-80% efficacy. Drug therapy has approximately 60% efficacy and sometimes is proarrhythmic. Moreover, preventive device therapy has been ineffective at suppressing atrial arrhythmias, and shocks are painful device-based therapy that has impacted patient acceptance of implantable cardiac devices (ICD's) both for atrial and ventricular defibrillation. | {
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1. Field of the Invention
The present invention relates to an image forming device, a bias voltage control method for the image forming device, and a computer program product.
2. Description of the Related Art
In an image forming device, with the aim of achieving reduction in the cost of a high-voltage power supply board, a technology is known in which an imaging sequence and an output constraint are set and a common transformer is used for charging and developing purposes; or a technology is known in which a constant-voltage element is configured in between outputs, and the output bias potential difference is maintained at a constant level so as to reduce the terminals of a high-voltage output unit.
For example, in Japanese Patent Application Laid-open No. 2012-53350, a technology is disclosed in which, with the aim of achieving reduction in the cost of a high-voltage power supply, a common transformer is used for a charging grid and a developing output. Moreover, a technology is disclosed in which constant-voltage elements are connected in between a regulation output and a developing output of a developing device, and the potential; difference between those outputs is maintained at a constant level. With that, in a high-voltage output unit, it becomes possible to use the same terminal for the regulation output and the developing output without making the circuitry complex (for example, see Japanese Patent No. 3507571).
However, in the conventional technologies mentioned above, in the case in which developing of reverse polarity to the polarity of charging is to be output for the purpose of cleaning a photosensitive member, it is not possible to obtain the desired potential difference between the constant-voltage elements. Hence, it is not possible to perform photosensitive member cleaning in a stable manner.
In view of the issues mentioned above, there is a need to enable cleaning of a photosensitive member in a stable manner without making the circuitry complex. | {
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1. Field of Invention
This invention concerns novel methods and apparatus for medical applications, specifically wound closure applications. More particularly, the invention manipulates blood fluids, or its components, in new ways to close tissue or vascular wounds.
2. Background Information
Numerous medical applications exist where sealing of biological tissue is desired. U.S. Pat. No. 5,510,102 to Cochrum identifies many of these including trauma of liver, spleen, pancreas, lung, bone, etc., cardiovascular and vascular, such as microvascular anastomoses, vascular grafts, intraoperative bleeding, and aortic repair, for thoracic surgery such as lung biopsy, for transplant of heart, renal, pancreas, lung, bone or bone marrow, for neurosurgery such as nerve anastomoses, or CSF leak repair, for endoscopic surgery, such as hemostasis in hepatic trauma, or bile duct repair, for interventional radiology, such as hemostasis for percutaneous liver biopsy or vascular occlusion, for gastrointestinal surgery such as colonic anastomoses, for obstetrics and gynecology such as rectovaginal fistulas, for pediatric and fetal surgery, for plastic surgery and burn repairs such as grafting process of cultured epidermis, for dermatology such as hair transplants, for dental surgery, for ophthalmic cataract surgery, for urology, for correction of urinary fistulas and such others. With such broad application of the present invention possible, one use is selected for method and apparatus illustrative continuity purposes throughout this document. The selected application is sealing of a vascular wound resulting from percutaneous entry as is frequently done in the performance of angiography, angioplasty, and atherectomy procedures.
Percutaneous vascular access is typically done in the context of performing some minimally invasive surgical procedure. Minimally invasive techniques are used to reduce trauma to the patient. Reduced trauma typically translates to improved patient comfort, less procedural complications, and lower costs. The vessel accessed is typically the femoral or radial artery. Access involves placement of an introducer's distal tip beneath the patient's skin and through the arterial wall. To the extent possible, percutaneous access preserves the integrity of tissue covering the artery. As a result, when the introducer is to be removed the arterial access site is not exposed and the arterial wound is preferably closed without cutting down through the overlaying tissue to expose the site.
To accomplish hemostasis at the wound, numerous methods of post-introducer arterial closure have been invented. Most of these are similar to each other in many respects with some novel differentiating characteristic separating them. Many of them rely upon the clotting cascades being initiated at the wound site. Many prior art devices may be broadly classified into two groups, those that passively support onset of the clotting cascades at the wound site and those that actively cause the clotting cascades at the wound site. By example, mechanical methods of holding the wound closed by clamping or suturing to prevent hemorrhaging are passive methods because they merely prevent continual flushing of the site as the clot attempts to take hold. To a lesser degree the body also does this naturally by vascular constriction. The second grouping—active clotting at the wound site—includes those methods which place a clot inducing material at the wound site. Such clot inducing formulations are many and typically either supply thrombin directly or potentially stimulate thrombin release at the wound site.
Disadvantages of the prior art vary based on the method employed. Generally speaking, passive devices like clamping or suturing are generally complex and/or expensive. Clamping for example can be labor intensive to administer manually and is uncomfortable for the patient by any means. Suturing on the other hand is complex and expensive because the wound site is typically small, remote, and blind to the physician placing the suture. Active devices are often costly and potentially dangerous. Active devices typically require placement of a clot-inducing foreign material in the patient which necessitates either expensive pretesting for potential allergic reactions or accepting the occasional adverse reaction which could lead to anaphylactic shock and even death as reported in J. Trauma, 31:408 (1991). Transmission of infectious disease can occur when the material used was manufactured from pooled human blood as reported in Opth. Surg., 23:640 (1992). Autologous preparations like fibrin glue as described in U.S. Pat No. 5,674,394 to Whitmore are well known but significant preparation with the associated labor and material costs are required and typically an additional thrombin material must still be added at the wound site.
Despite the need for a device and method which overcomes the limitations of the prior art, none insofar as is known has been proposed or developed until the present invention.
Accordingly, it will be appreciated that there is a need for an efficient way of closing wounds. The present inventions provide advantages over the prior devices and the prior methods used to close wounds, and also offers other advantages over the prior art and solves other problems associated therewith. | {
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This invention relates to a method and a device for printing films housed in cartridges.
A conventional device for printing images on a film onto printing paper has a scanner unit and a printing/exposure means arranged along a film feed unit for feeding films in a straight line. The scanner unit reads printing conditions such as image density from a film before printing it. Based on the data thus obtained, the light from a light source is adjusted with a light adjusting filter and the thus adjusted light is used to print film images onto printing paper.
To print films with this type of printers, films have to be pulled out of and detached from cartridges. The films are then fed into the film feed unit as it is or after splicing them in a roll form.
With the conventional device, while the scanner unit is reading image density and other printing data of one film, the printing/exposure unit cannot print another film. While the latter is printing one film, the former cannot read printing data of another film. In other words, these units cannot be driven concurrently, so that the processing speed was insufficient. In order to increase the processing speed, it was proposed to drive the above two units independently of each other and to provide a loop guide therebetween to adjust the film feed rate.
When printing developed films, they may be fed in strips or in a roll after separating them from cartridges. Otherwise, they may be processed without separating them from cartridges. But in order to process films without detaching them from cartridges, a separate driving unit is needed to unwind and rewind films from and into cartridges.
An object of this invention is to provide a method and device for printing films which can print one film in a printing/exposure unit while reading image data in a scanner unit by using a rotary table, which need no separate driving means for opening and closing doors of cartridges mounted on the rotary table and no wire connecting work. | {
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During the past decade there has been substantial effort expended to develop materials for the repair and replacement of various tissues, especially cartilage tissue in the knee joint. Although various polymeric biomaterials have been developed for tissue repair, these biomaterials suffer from immune incompatibility and improper distribution of stress. Furthermore, the use of material from animals, such as cow hide or cartilage from pigs or sharks, has raised concerns of possible contamination by infectious agents, such as prions. Thus, improved materials of biological origin that have improved compatibility, present a reduced risk of contamination, and provide the proper biomechanical characteristics for tissue repair are needed. In addition, these materials will preferably promote the interaction between native tissue and implanted cells. The ability to control the rate of biodegradation of these material is also desirable. | {
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1. Field of the Invention
The present invention relates to a power supply apparatus and an image forming apparatus in which the operation of a control circuit is started and stopped in accordance with an input AC voltage.
2. Description of the Related Art
Power supply apparatuses that employ switching elements are widely prevalent due to having a high conversion efficiency. Japanese Patent Laid-Open No. 2007-006614 proposes a current resonance power supply in which the voltage between both ends of one switching element is detected, and another switching element is switched on when the detected voltage has risen to a predetermined voltage or higher, thus preventing a short circuit caused by resonance deviation when an electrical overload occurs.
According to Japanese Patent Laid-Open No. 2007-006614, a voltage detection circuit detects the voltage at both ends of one switching element and outputs the detected voltage to a control circuit. Generally, only a low-level voltage can be applied to the input terminal of a control circuit, therefore the voltage detection circuit needs a voltage-dividing circuit for dividing a relatively high voltage such as a commercial voltage. Since this voltage-dividing circuit consumes power even when the power supply apparatus shifts to an energy-saving operation mode (a low load mode), power consumption tends to rise.
Incidentally, a control IC controls the operation of the switching elements included in a power supply apparatus, and the control IC includes an enable terminal. The control IC starts operating when a voltage Vsns applied to the enable terminal rises to an operation start voltage Vstart or higher. However, there are cases where a decrease occurs in an input AC voltage Vin that is supplied from a commercial power supply to the power supply apparatus after the control IC has started operating. If the input AC voltage Vin falls to an operation stop voltage Vstop or lower, the current flowing to the primary side becomes excessive in an attempt to maintain the voltage on the secondary side. When the current on the primary side becomes excessive, elements become damaged and the conversion efficiency decreases. In view of this, the control IC is designed so as to stop operating when the input AC voltage Vin falls to the operation stop voltage Vstop or lower.
FIG. 6A shows the relationship between the voltage Vsns at the enable terminal of the control IC and the input AC voltage Vin in an ideal state. In this example, the control IC starts operating when the input AC voltage Vin rises to 80 V or higher, and the control IC stops operating when the input AC voltage Vin falls to 60 V or lower. The control IC starts operating when the voltage Vsns at the enable terminal rises to the operation start voltage Vstart or higher, which is proportional to the input AC voltage Vin of 80 V, and the control IC stops operating when the voltage Vsns falls to the operation stop voltage Vstop or lower, which is proportional to the input AC voltage Vin of 60 V. In this way, the operation start voltage Vstart needs to correspond to 80 V, and the operation stop voltage Vstop needs to correspond to 60 V. However, the operation start voltage Vstart and the operation stop voltage Vstop vary under various circumstances.
FIG. 6B shows the case where the operation start voltage Vstart has become too high. In this example, the operation start voltage Vstart has risen to a voltage that corresponds to the input AC voltage Vin of 100 V, and therefore the control IC cannot start even if the input AC voltage Vin has risen to 80 V or higher.
FIG. 6C shows the case where the operation stop voltage Vstop has become too low. In this example, the operation stop voltage Vstop has decreased to a voltage that corresponds to the input AC voltage Vin of 45 V, and therefore the control IC fails to stop even if the input AC voltage Vin has fallen to 60 V or lower. | {
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The present invention is directed to a fan array fan section utilized in an air-handling system.
Air-handling systems (also referred to as an air handler) have traditionally been used to condition buildings or rooms (hereinafter referred to as “structures”). An air-handling system is defined as a structure that includes components designed to work together in order to condition air as part of the primary system for ventilation of structures. The air-handling system may contain components such as cooling coils, heating coils, filters, humidifiers, fans, sound attenuators, controls, and other devices functioning to meet the needs of the structures. The air-handling system may be manufactured in a factory and brought to the structure to be installed or it may be built on site using the necessary devices to meet the functioning needs of the structure. The air-handling compartment 102 of the air-handling system includes the inlet plenum 112 prior to the fan inlet cone 104 and the discharge plenum 110. Within the air-handling compartment 102 is situated the fan unit 100 (shown in FIGS. 1 and 2 as an inlet cone 104, a fan 106, and a motor 108), fan frame, and any appurtenance associated with the function of the fan (e.g. dampers, controls, settling means, and associated cabinetry). Within the fan 106 is a fan wheel (not shown) having at least one blade. The fan wheel has a fan wheel diameter that is measured from one side of the outer periphery of the fan wheel to the opposite side of the outer periphery of the fan wheel. The dimensions of the handling compartment 102 such as height, width, and airway length are determined by consulting fan manufacturers data for the type of fan selected.
FIG. 1 shows an exemplary prior art air-handling system having a single fan unit 100 housed in an air-handling compartment 102. For exemplary purposes, the fan unit 100 is shown having an inlet cone 104, a fan 106, and a motor 108. Larger structures, structures requiring greater air volume, or structures requiring higher or lower temperatures have generally needed a larger fan unit 100 and a generally correspondingly larger air-handling compartment 102.
As shown in FIG. 1, an air-handling compartment 102 is substantially divided into a discharge plenum 110 and an inlet plenum 112. The combined discharge plenum 110 and the inlet plenum 112 can be referred to as the airway path 120. The fan unit 100 may be situated in the discharge plenum 110 as shown), the inlet plenum 112, or partially within the inlet plenum 112 and partially within the discharge plenum 110. The portion of the airway path 120 in which the fan unit 100 is positioned may be generically referred to as the “fan section” (indicated by reference numeral 114). The size of the inlet cone 104, the size of the fan 106, the size the motor 108, and the size of the fan frame (not shown) at least partially determine the length of the airway path 120. Filter banks 122 and/or cooling coils (not shown) may be added to the system either upstream or downstream of the fan units 100.
For example, a first exemplary structure requiring 50,000 cubic feet per minute of air flow at six (6) inches water gage pressure would generally require a prior art air-handling compartment 102 large enough to house a 55 inch impeller, a 100 horsepower motor, and supporting framework. The prior art air-handling compartment 102, in turn would be approximately 92 inches high by 114 to 147 inches wide and 106 to 112 inches long. The minimum length of the air-handling compartment 102 and/or airway path 120 would be dictated by published manufacturers data for a given fan type, motor size, and application. Prior art cabinet sizing guides show exemplary rules for configuring an air-handling compartment 102. These rules are based on optimization, regulations, and experimentation.
For example, a second exemplary structure includes a recirculation air handler used in semiconductor and pharmaceutical clean rooms requiring 26,000 cubic feet per minute at two (2) inches water gage pressure. This structure would generally require a prior art air-handling system with a air-handling compartment 102 large enough to house a 44 inch impeller, a 25 horsepower motor, and supporting framework. The prior art air-handling compartment 102, in turn would be approximately 78 inches high by 99 inches wide and 94 to 100 inches long. The minimum length of the air-handling compartment 102 and/or airway path 120 would be dictated by published manufacturers data for a given fan type, motor size and application. Prior art cabinet sizing guides show exemplary rules for configuring an air-handling compartment 102. These rules are based on optimization, regulations, and experimentation.
These prior art air-handling systems have many problems including the following exemplary problems: Because real estate (e.g. structure space) is extremely expensive, the larger size of the air-handling compartment 102 is extremely undesirable. The single fan units 100 are expensive to produce and are gene custom produced for each job. Single fan units 100 are expensive to operate.
Single fan units 100 are inefficient in that they only have optimal or peak efficiency over a small portion of their operating range. If a single fan unit 100 breaks down, there is no air conditioning at all. The low frequency sound of the large fan unit 100 is hard to attenuate. The high mass and turbulence of the large fan unit 100 can cause undesirable vibration.
Height restrictions have necessitated the use of air-handling systems built with two fan units 100 arranged horizontally adjacent to each other. It should be noted, however, that a good engineering practice is to design air handler cabinets and discharge plenums 110 to be symmetrical to facilitate more uniform air flow across the width and height of the cabinet. Twin fan units 100 have been utilized where there is a height restriction and the unit is designed with a high aspect ratio to accommodate the desired flow rate. As shown in the Greenheck “Installation Operating and Maintenance Manual,” if side-by-side installation was contemplated, there were specific instructions to arrange the fans such that there was at least one fan wheel diameter spacing between the fan wheels and at least one-half a fan wheel diameter between the fan and the walls or ceilings. The Greenheck reference even specifically states that arrangements with less spacing will experience performance losses.” Normally, the air-handling system and air-handling compartment 102 are designed for a uniform velocity gradient of 500 feet per minute velocity in the direction of air flow. The two fan unit 100 air-handling systems, however, still substantially suffered from the problems of the single unit embodiments. There was no recognition of advantages by increasing the number of fan units 100 from one to two. Further, the two fan unit 100 section exhibits a non-uniform velocity gradient in the region following the fan unit 100 that creates uneven air flow across filters, coils, and sound attenuators.
It should be noted that electrical devices have taken advantage of multiple fan cooling systems. For example, U.S. Pat. No. 6,414,845 to Bonet uses a multiple-fan modular cooling component for installation in multiple component-bay electronic devices. Although some of the advantages realized in the Bonet system would be realized in the present system, there are significant differences. For example, the Bonet system is designed to facilitate electronic component cooling by directing the output from each fan to a specific device or area. The Bonet system would not work to direct air flow to all devices in the direction of general air flow. Other patents such as U.S. Pat. No. 4,767,262 to Simon and U.S. Pat. No. 6,388,880 to El-Ghobashy et al. teach fan arrays for use with electronics.
Even in the computer and machine industries, however, operating fans in parallel is taught against as not providing the desired results except in low system resistance situations where fans operate in near free delivery. For example, Sunon Group has a web page in which they show two axial fans operating in parallel, but specifically state that if ‘the parallel fans are applied to the higher system resistance that [an] enclosure has, . . . less increase in flow results with parallel fan operation.” Similar examples of teaching against using fans in parallel are found in an article accessible from HighBeam Research's library (http://stati.highbeam.com) and an article by Ian McLeod accessible at (http://www.papstplc.com). | {
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Modern storage systems typically include multiple standalone storage devices that are passive and whose performance characteristics are fixed in general once manufacturing is complete. A processor (e.g., RAID controller) executing software (firmware) is necessary to add intelligence to make the collection of unintelligent storage devices work as a unit. Because storage devices, such as solid state drives (SSDs), may be also controlled through the software or firmware, efforts have been made to control operating characteristics of a solid state drive according to the use environment.
The traditional approaches for satisfying user qualification tests require a manufacturer to provide last minute engineering processes to customize the storage devices for each customer. Customers typically wish to recalibrate their software systems whenever new models of storage devices are adopted because the characteristics of the storage devices are widely heterogeneous. However, the assumptions for one storage device are often not valid with another device. Consequently, traditional customization approaches are not sustainable in part because the manufacturer's engineering cost increases with the number of storage devices and customers requiring customization.
Therefore, a framework that enables an easy reconfiguration of storage systems on the behalf of customers is crucial. For instance, solid state disk (SSD) optimization software, such as Magician™ by Samsung, tunes performance of SSDs for a customer's system. However, customers have very limited optimization options, the optimization metrics are device-oriented in contrast to user-oriented, and the optimization is not controlled or quantifiable. In addition, storage device characteristics can change over time due to the degradation of the storage media such as wearing and fatigue. This can violate the initial assumption that the customer had, which cannot be perceived easily until malfunctions happen at the user level.
Another type of reconfigurable storage device process allows a customer to select individual features to configure a storage device. In this approach, instead of adjusting a customer's system to a new storage device, a reconfigurable storage device allows the customer to adjust the storage devices to their systems, which simplifies the maintenance and upgrade process.
Although reconfigurable storage devices can provide more flexibility in performance optimization and allow the customers to do customization, several challenges remain. One challenge is that the recalibration process constitutes a combinatory problem whose complexity increases exponentially with the number of features of the storage device to customize. In other words, current approaches do not provide systematic configuration method for feature selection. For example, if a customer changes the value of three features, it may be difficult for the customer to determine what effect the combination of features will be on the performance of the storage device.
A related challenge is that the selection of features by the customer is accomplished through a software user interface in which the customer selects the features manually. Manual selection of features without a systematic configuration method or performance guideline results is essentially a trial and error process.
Finally, the conventional reconfiguration process does not address the effects of storage device characteristics changing over time due to the degradation of the storage media. Such changes can render the original selection of features for a particular use environment no longer valid.
Accordingly, the trend of software-defined storage (SDS) in which storage resources required by an application can be defined by software and provisioned automatically requires an improved reconfigurable storage process that is more flexible. | {
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1. Field of Invention
The present invention relates to infrared surveys of geographical areas and, more particularly, to an improved survey system and method using infrared and color television images and having means for determining and recording coordinates of points of interest of the survey.
2. Description of the Prior Art
Geographical surveys utilizing infrared sensors are extremely useful for a number of activities. For example, such surveys are applicable to detection of gas pipeline links; detection of problems in electric power transmission lines; determining the density of populated areas; search and rescue missions; pollution studies; and timber surveys. Infrared detection systems provide information concerning areas having a distinct temperature differential from the background temperatures and use of such systems for surveys is known in the art. However, a major problem in such surveys that has not been adequately solved is accurate determination of the location of small ground features detected by an infrared system.
A typical prior art infrared survey system is disclosed by Dibbero, U.S. Pat. No. 3,076,961. An airborne multiple sensor system is used having an infrared camera, a television camera, and a radar scanner. The multiple sensors provide detection and identification of camouflaged targets such as required in military operations. No means for producing accurate ground coordinates of detected targets is provided. Parker et al., in U.S. Pat. No. 3,752,915, teach recording on magnetic tape of thermal ground and reference data obtained from an airborne scanner to produce color images. U.S. Pat. No. 4,516,158 to Grainge et al. shows two airborne infrared scanners that scan in different directions.
None of the above systems provide accurate identification of ground coordinates, such as latitude and longitude, of located targets nor altitude from which the survey was made. Therefore, a need remains for an accurate survey system utilizing infrared scanning, color video, and video recording that includes means for recording the latitudes and longitudes of small areas of interest located during the survey. For aerial surveys in which a system provides latitude and longitude coordinates, which provides means for locating the coordinates with a ground vehicle is required. | {
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1. Field of the Invention
The present invention generally relates to a lamp unit adapted to be disposed above a front fender for overhanging a motorcycle front wheel and, more particularly, to the lamp unit of a design in which a lens member covering at least head lamps can provide varying, but appealing designs one at a time when viewed from front or slantwise from front, depending on the direction of travel of imagewise rays of light reflected from the fender.
2. Description of the Prior Art
As is well known to those skilled in the art, most of the conventional motorcycles have a front fairing or cowling mounted on a front portion thereof. A lamp unit is mounted in the front fairing. The lamp unit encases therein at least one head lamp for illuminating forwardly of the motorcycle and at least one position lamp adapted to be lit during the dusk or parking to provide an indication of the motorcycle to the oncoming vehicles, and is available in two types; a single lamp design having a single lens member disposed at a position intermediate of the width of the motorcycle, and a dual lamp design having left and right lens members one for each of left and right head lamps. The single lamp design and the dual lamp design have their own unique appearances and can therefore provide different impressions. | {
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End users appreciate quality images and video. They also appreciate the ability to easily use devices that create such images and video. Designers and manufacturers may, therefore, endeavor to create and provide technology directed toward at least some of these objectives. | {
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The present invention relates to absorbent articles, and more particularly to absorbent articles having wetness indicating graphics providing an interactive training aid.
The toilet training process may incorporate a wide variety of different aspects, including many training techniques and training aids that may be used by parents and caregivers, hereinafter simply referred to as caregivers. One aspect of the total toilet training process is the change from diapers to training pants to help the child understand that he or she should now use the toilet just like adults. Another aspect of the total toilet training process includes caregiver instruction as a positive encouragement and reinforcement to the child that he or she should now be using a toilet instead of diapers. Although the use of training pants and positive encouragement from the caregiver has been helpful in the toilet training process, there is still much room for improvement. Specifically, caregivers are still searching for easier and quicker ways to guide their children successfully through the toilet training process.
Many caregivers have difficulty in determining the readiness of a child to begin the toilet training process, and underestimate the difficulty of teaching the toilet training process to young children. If a child does not respond to an initial toilet training instruction or introduction, the caregiver can be at a loss for finding techniques, methods, or teaching tools to encourage the child to master the art of toilet training. Thus, while various teaching tools such as books, videotapes, charts with stickers, personalized toilets, and interactive toilet training kits are available, there remains a need for new and improved educational and motivational mechanisms to facilitate the toilet training process. | {
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Liquid crystal display panels are increasingly used for the general display of alpha-numeric information and in particular they are finding application to such areas as control panels in the cockpit of aircraft or the like where the pilot user may view the display by looking down at an angle from the horizontal.
An inherent problem encountered with reflective dynamic scattering liquid crystal displays used in such applications is that of light trapping the specular reflection off of the display surface while providing illumination at angles where liquid crystal scattering is efficient.
Efforts of the prior art to use reflective surfaces to provide light to liquid crystal and other display devices are typified by the following U.S. Pat. Nos. 3,728,007 to Myrenne et al; 3,838,909 to Fitzgibbons; 3,920,311 to Tsuda; and 3,924,932 to Yamamoto. None of these discusses or solves the above problem dealt with by the present invention.
It is an object of this invention to provide a reflective dynamic scattering liquid crystal display and mounting arrangement therefore which solves this light trapping problem and is suitable for such cockpit use. | {
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1. Technical Field
The present invention relates to rotating electric machines which have a coil formed by arranging each corresponding pair of end portions of electric conductors to adjoin each other and welding them at end surfaces thereof, and to methods of manufacturing the rotating electric machines.
2. Description of Related Art
There are known rotating electric machines which have a coil formed by arranging each corresponding pair of end portions of electric conductors to adjoin each other and welding them at end surfaces thereof.
For example, Japanese Patent No. JP3303854B2 discloses an automotive alternator which has a stator coil formed by welding a plurality of substantially U-shaped conductor segments to one another. More specifically, each of end portions of the conductor segments has a cut (or notch) formed therein. Each corresponding pair of the end portions of the conductor segments are arranged to have parts thereof where no cut is formed adjoin each other, and then welded at end surfaces thereof. Consequently, with the cuts formed in the end portions of the conductor segments, it is possible to weld each corresponding pair of the end portions of the conductor segments with a reduced heat input to the pair of the end portions during the welding.
On the other hand, however, due to the cuts, it may become easy for the molten metal mixture to sag outside the pair of the end portions of the conductor segments during the welding. Consequently, it may become difficult for the molten metal mixture to form a uniform weld bead shape. As a result, the strength of a weld formed between the pair of the end portions of the conductor segments may become uneven and thus local stress concentration may occur in the weld. | {
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1. Field of the Invention
This invention relates generally to radio frequency power amplifiers and, more particularly, the invention relates to methods of managing the signal to noise floor ratio as the operational bandwidth of a digital linearized predistortion amplifier is expanded.
2. Description of the Related Art
Radio frequency power amplifiers are widely used to transmit signals in communications systems. Typically a signal to be transmitted is concentrated around a particular carrier frequency occupying a defined channel. Information is sent in the form of modulation of amplitude, phase, and/or frequency such that the information is represented by energy spread over a band of frequencies around the carrier frequency. In many schemes the carrier itself is not sent since it is not essential to the communication of the information.
When a signal that contains amplitude variations is amplified, it will suffer distortion if the amplifier does not exhibit a linear amplitude and phase transfer characteristic. This means that the output is not linearly proportional to the input. The signal will also suffer distortion if the phase shift, which the amplifier introduces, is not linear over the range of frequencies present in the signal or if the phase shift caused by the amplifier varies with the amplitude of the input signal. The distortion introduced typically includes intermodulation of the components of the input signal. The products of the intermodulation appear within the bandwidth of the signal causing undesirable interference. The products of the intermodulation also extend outside the bandwidth originally occupied by the signal. This can cause interference in adjacent channels and violate transmitter licensing and regulatory spectral emission requirements. Although filtering can be used to remove the unwanted out of band distortion, this is not always practical, especially if the amplifier is required to operate on several different frequencies.
Distortion products that occur at multiples of the carrier frequency can also be produced in a non-linear amplifier, but are relatively easy to remove by filtering. Intermodulation is also a problem when multiple signals are amplified in the same amplifier even if individually they do not have amplitude variations. This is because the combination of the multiple signals produces amplitude variations as the various components beat with each other by adding and subtracting as their phase relationships change.
Amplifiers can introduce some distortion even if they are well designed. Perfect linearity over a wide range of amplitude is difficult to realize in practice. In addition, as any amplifier nears its maximum output power capacity, the output no longer increases as the input increases. At this point the amplifier is not regarded as linear. A typical amplifier becomes significantly non-linear at a small fraction of its maximum output capacity. This means that in order to maintain linearity, the amplifier is often operated at an input and output amplitude which is low enough that the signals to be amplified are in a part of its transfer characteristic that is substantially linear. This is a method of operation, described as xe2x80x9cbacked off,xe2x80x9d in which the amplifier has a low supplied power to transmitted power conversion efficiency. A xe2x80x9cClass Axe2x80x9d amplifier operating in this mode may be linear enough for transmitting a signal cleanly but might typically be only 1% efficient. This wastes power and means that the amplifier has to be large and relatively expensive. In addition, the wasted power is dissipated as heat, which generally must be removed by cooling means.
Communication schemes using signals which have constant amplitude with frequency and phase modulation can use highly non-linear amplifiers. These types of signals are unaffected by the distortion and the amplifiers can be smaller, cooler, more power efficient and less expensive. Modulation of this type is used in conventional radio paging systems, which use CPFSK modulation.
Many of the newer, bandwidth efficient modulation schemes have both amplitude and phase variations. There is also frequently a desire to be able to transmit multiple signals on different channels through a single amplifier. This reduces the number of separate amplifiers required and avoids the need for large and costly high level output signal combining filters, which have undesirable power losses.
There is a need for linear amplifiers which are compact, power efficient and inexpensive. Linearized amplifiers can be made by correcting for the non-linearities of amplifiers using methods such as Cartesian feedback, predistortion, and feedforward correction.
Cartesian feedback is a method in which a monitoring system looks at the output of the amplifier and attempts to alter the input of the amplifier so that it produces the intended output. This is accomplished using a direct feedback loop. The delay in the feedback path can cause the input signal to be modified too slowly to provide effective compensation, especially with signals at higher bandwidths.
The traditional predistortion method attempts to correct for the non-linear transfer characteristic of an amplifier by forming an inverse model of its transfer characteristic. This characteristic is applied to the low level signal at the input of the amplifier in a nonlinear memory-less function to predistort the signal such that the amplified signal appears substantially undistorted. This method is capable of excellent results over a relatively small bandwidth. The non-linear memory-less function is updated to account for variations in the amplifier transfer characteristic and this is done by monitoring the output and periodically updating the correction parameters. The non-linear coefficients of the memory-less function may be changed as often as every sample using the values stored in memory.
Feedforward is a method that derives a signal which represents the inverse of the distortions produced by the amplifier. This can be done by comparing the amplifier input and output to extract a distortion signal. A small linear amplifier is used to amplify the distortion signal. The amplified distortion signal is then subtracted from the main amplifier output. This method gives good results over a relatively wide bandwidth. However, balancing the amplitude and delay of the distortion signal so that it cancels the main amplifier errors exactly is difficult to implement.
Both traditional feedforward and predistortion are widely used in commercial products which can amplify multiple signals and operate over a wide range of amplitudes. Both methods are quite complex and the power efficiencies are still not excellent. Feedforward amplifiers are typically only 5% efficient. The complicated processing requirements add to the cost and the power used and significant cooling capacity is still required to remove waste heat. Predistortion is capable of excellent results, but only over a relatively small bandwidth.
The present invention provides methods of managing the signal to noise floor ratio exhibited in individual subbands as the operational bandwidth of a digital linearized predistortion amplifier is expanded.
In one aspect of the invention, a digital input signal is separated into subbands of lower bandwidth. The digital input signal is preferably a wideband signal that has one or both of the following characteristics: (a) the signal exists at one or more frequencies within an operating bandwidth within a time interval that is the reciprocal of the total information bandwidth; (b) the signal consists of multiple information bearing subcarriers and has a spectral occupancy that exceeds 0.1% of the RF carrier frequency. Each of the digital subband signals, which has a lower power than the digital input signal, is separately converted to an analog subband signal using a separate DAC. The separately converted analog subband signals are combined to form an analog input signal. By separating the digital signal into subbands, separate DACs can be used and the power of the signal to be handled by any one DAC is reduced.
In another aspect of the invention, a digital correction signal is created by taking the difference between a digital predistortion signal and the digital input signal. The digital predistortion signal, which is a signal that is typically passed through a Digital to Analog Converter (DAC) and supplied to a non-linear amplifier, can be created using presently available techniques. In accordance with the invention, however, the digital input signal is removed from the digital predistortion signal to leave only the digital correction signal, which has a much lower power than the digital predistortion signal. The digital correction signal and the digital input signal (or its subbands) are separately converted to analog signals using separate DACs. The converted analog signals are combined by analog summation to form an analog predistorted signal. The analog predistorted signal is passed on to a non-linear amplifier.
The aforementioned aspects of the invention result in the separation of a digital signal into separate signals of lower power. In the prior art, a single DAC has been used to convert a combined signal of much higher power. In accordance with the present invention, however, multiple DACs are employed and each DAC converts a digital signal of a lower power. As a result, the available levels of quantization of each DAC are applied to a lower power signal and the lower power per quantum ratio provides a better signal to noise ratio. Accordingly, substantially the entire dynamic range of each DAC can be used to convert a signal to analog form.
In another aspect of the invention, each analog signal is passed through a separate narrow band reconstruction filter before the analog signals are combined. Each reconstruction filter can be configured specifically for a narrow frequency range. By passing each converted signal through a separate narrow reconstruction filter, a significantly higher signal to wideband noise ratio for the composite signal can be achieved. The use of separate reconstruction filters, however, may introduce relative gain, phase, and delay inconsistencies between the separate signals. These relative inconsistencies are caused by the analog nature of the reconstruction filters, which are preferably configured to handle specific narrow frequency bands.
In order to correct the relative inconsistencies between the separate signals, a digital correction filter is introduced in-line along each subband signal path before the DAC. The correction filters are driven by an Adaptive Control Processing and Compensation Estimator (ACPCE) block, which adaptively generates compensation parameters for the filters based on observations of the digital input signal and the output of the amplifier. | {
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1. Field of the Invention
This invention relates to new and useful improvements for liquid pumps and more particularly, to high pressure pumps for delivering a stream of water or other liquid at high velocity for jet washing or cleaning of surfaces.
2. Brief Description of the Prior Art
Sergeant U.S. Pat. No. 745,298 discloses a compressor having a series of pistons of varying diameter for compressing gasses.
Hoerbiger U.S. Pat. No. 1,759,617 discloses a gas compressor with a pair of line cylinders of different diameter and a larger and smaller piston for compression.
Wineman U.S. Pat. No. 2,365,234 discloses a pump having two different cylinders of varying diameter in line and a single piston fitting both the larger and smaller cylinders for delivering liquid and gasses to a common system.
Green U.S. Pat. No. 3,155,041 discloses a pressure apparatus comprising a pump having two or more cylinders of varying diameter and pistons fitting said cylinders and operated by a single pump rod.
There has been a need for a satisfactory high-pressure pump for delivering water or other liquid at very high velocity for jet washing or cleaning of various surfaces. | {
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A network packet carries data via protocols that the Internet uses, such as Transmission Control Protocol/Internet Protocol/Ethernet Protocol (TCP/IP/Ethernet). A typical switch is able to modify various fields of incoming packets prior to sending the packets out to a destination or to another switch. Incoming packets are modified for various reasons, such as where the packets are being forwarded to, the protocol the destination supports, priority of the packets, incoming format of the protocol header, etc. Since network protocols are evolving, one or more fields of a protocol header can be optional, which complicates the hardware of the switch as a given field within a protocol header may not be always at a fixed offset.
During modification of a packet, the prior art switch linearly processes each protocol layer in the packet. Such processing can create network related performance issues, including latency, which can cause an implementation to overprovision processing resources. | {
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The present invention relates to non-aqueous electrolyte secondary batteries using non-aqueous electrolyte with lithium ion conductivity where material capable of incorporating and releasing lithium is used as a negative active material, and in particular, it relates to novel negative active materials capable of proposing improved high-reliable secondary batteries with a longer service life having a satisfactory charge and discharge characteristic of a high voltage and high energy density.
Non-aqueous electrolyte batteries using lithium as a negative active material have various advantages including high reliability ranging long periods due to smaller amounts of self-discharge in addition to a high voltage and higher energy density, therefore they have widely been used as primary batteries of power supplies for memory backup, cameras and the like. However in recent years, following the remarkable development of portable type electronics equipment and devices, communication equipment and devices and so forth, various kinds of equipment and devices have been realized requiring larger current outputs for batteries as a power supply. It is therefore strongly desired to produce high energy density secondary batteries capable of recharging and redischarging from the view point of economics, compact size, and light-weight of the devices. For this reason, the research and development for more satisfactory non-aqueous electrolyte secondary batteries have been considerably promoted, a part of which is now in practical use, however unsatisfactory characteristics still remain in energy density, charge and discharge cycle service life, and reliability.
Conventionally, as a positive active material constituting a positive electrode of the secondary battery of this kind there have been found three kinds of types depending on charge and discharge reaction patterns. Namely, in the first type, only lithium ions (cation) are input into and output from between layers of the crystal, lattice positions or gaps among lattices of the crystal by means of intercalation and deintercalation reactions and the like as is the case of metal chalcogenide such as TiS.sub.2, MoS.sub.2, NbSe.sub.3 and the like, and metal oxide such as MnO.sub.2, MoO.sub.3, V.sub.2 O.sub.5, Li.sub.x CoO.sub.2, Li.sub.x NiO.sub.2, Li.sub.x Mn.sub.2 O.sub.4, and the like. The second type is a type in which mainly only anion is stably input or output by the doping or undoping reactions as in the case of conductive polymers such as polyaniline, polypyrrole, polyparaphenylene and the like. The third type is a type in which both lithium cation and anion can be input and output as in the case of layer-like structure graphite compounds and conductive polymers such as polyacene and the like (intercalation, deintercalation, or dope, undope or the like).
On the other hand, in the negative active material of the battery of this kind, since the use of metal lithium in a simple substance gives the basest electrode potential, it is preferable that the battery combined with the positive electrode using positive active material as described above has the highest voltage and the highest energy density. However, the problem arises in considerable deterioration with charge and discharge and results in a shorter cyclic life because of the generation of dendrite or passive state compounds on the negative electrode due to the charge and discharge. In order to solve this problem, for the negative active material, various possible materials capable of incorporating and releasing lithium ions are proposed; namely, (1) alloy of lithium with other metals such as Al, Zn, Sn, Pb, Bi and Cd; (2) intercalation compounds or insertion compounds in which lithium ions are incorporated into the crystal structure of inorganic compounds such as WO.sub.2, MoO.sub.2, Fe.sub.2 O.sub.3, and TiS.sub.2, graphite, and carbonaceous materials obtained by baking organic materials; (3) conductive polymers such as polyacene, polyacethylene and the like in which lithium ions are doped.
However, in general, in case where, as a negative active material, the negative electrode using materials capable of incorporating and releasing lithium ions (other than metal lithium as described above) is combined with the positive electrode using the positive active material described above to constitute a battery, an electrode potential of the negative active material is nobler than an electrode potential of metal lithium, and the drawback therefore arises in that an operating voltage of the battery is lowered than when using metal lithium in the simple substance as a negative active material. For example, the operating voltage is lowered by 0.2 to 0.8 V when using alloys of lithium with Al, Zn, Pb, Sn, Bi, Cd or the like, by 0 to 1 V when using lithium intercalation compound of carbon, and by 0.5 to 1.5 V when using lithium ion insertion compound such as MoO.sub.2 or WO.sub.2.
Since elements other than lithium are involved as negative electrode constituent elements, the capacity and energy density per volume and weight are considerably lowered.
Further, in case (1) where the alloys of lithium are used with the other metals, a problem occurs because the utilization-efficiency of lithium is low during charge and discharge and repeating charge and discharge causes cracks or breaks in the electrode which results in a shorter cyclic life. It (2) where the battery uses the lithium intercalation compound or insertion compound, deteriorations such as decay of the crystal structure and generation of irreversible substances arise in the case of excess charge and excess discharge, and further there is a drawback of a lower output voltage of the battery because of the higher (nobler) electrode-potential. In case (3), where the conductive polymer is used, the problem is that the charge and discharge capacity, in particular, the charge and discharge capacity per unit volume, is small.
For these reasons, to obtain a secondary battery with a long cyclic service life having a graded charge and discharge characteristic with a high voltage and a high energy density, there is required a negative active material having a larger effective charge and discharge capacity, that is, a larger amount of reversible incorporation and release of lithium ions with a lower (baser) electrode potential for lithium but without deteriorations such as decay of the crystal structure and generation of irreversible substances and the like due to the incorporation and release of the lithium ions during charging and discharging. | {
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Tagging apparatuses include, and may in their most rudimentary form consist exclusively of, a fastener dispensing gun or similar device having a hollow needle through which the fasteners are dispensed and onto which the articles to be tagged and the tags themselves are impaled. When the apparatus is of this most basic type, the operator manually effects impalement of the tags and articles upon the needle of the dispensing device, and then manually actuates the device to effect insertion of an interconnecting filamentary fastener through them. Although perhaps suitable for some occasional tagging operations, the foregoing manual technique is too slow, fatiguing and hazardous for high-production tagging operations, particularly those in which more than a single tag is to be attached to each article. In recognition of this fact, automatic tagging apparatuses have heretofore been proposed.
Illustrative of the previously proposed automatic tagging apparatuses is that disclosed in U.S. Pat. No. 4,235,161, issued Nov. 25, 1980 to Kunreuther and Beringhaus. Such apparatus includes means for mounting the fastener dispensing device in a fixed position, means for effecting automatic operation of the device in response to operator actuation of a readily accessible switch, and means for conducting tags from a supply hopper or the like to and onto the hollow needle of the dispensing device. In one embodiment the apparatus has two tag conveying assemblies that operate in sequence with each other to lessen the time required to secure a plurality of tags to each garment. An apparatus of the aforesaid automatic type can greatly increase the speed, efficiency and safety of the tagging operations, and therefore should significantly reduce the cost of such operations. However, this desirable result has not always been realized by the automatic tagging apparatuses heretofore commercialized, for a variety of reasons. Due to their size and/or complexity, such machines may be unduly expensive and difficult to manufacture, ship, assemble, adjust and/or maintain. Since adjustment of the apparatus is normally necessary not only during initial setup thereof, but also whenever there is a significant change in the size of the tags to be secured to the garments, a capability for rapid adjustment of the apparatus is particularly desirable. An additional disadvantage of those previously proposed "double" apparatuses having a pair of tag supplying mechanisms is that such mechanisms are both used only when a plurality of tags are to be secured to an article. When the tagging operation requires only a single tag per article, one of the tag conveying mechanisms remains unused and unusable. The economic wastefulness of this situation is aggravated if, as might well be the case, there is a concurrent need for another "single" tagging machine in the same plant where the only partially-used "double" machine is present.
With the foregoing in mind, a primary object of the present invention is the provision of a modular tagging apparatus that is of highly compact, efficient, economical and reliable construction, and that may be easily adjusted and/or modified to accommodate tags of differing size and/or to be uable in either single-tag or multiple-tag tagging operations. | {
"pile_set_name": "USPTO Backgrounds"
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The present application relates generally to communication systems and, more particularly, to communication systems in which data is exchanged between a card reader and a contactless smartcard.
Contactless smartcards are widely used to purchase goods and services. For example, it is now possible to pay for gasoline, groceries, and transit fares simply by waving a contactless smartcard in the vicinity of a card reader. Smartcards provide the cardholder with a quick and convenient way to transfer value and often can be recharged or otherwise linked to a line of credit.
A card reader communicates with a contactless smartcard using electromagnetic radiation. Card transactions often involve an over-the-air exchange of sensitive information such as account numbers, key values, and other identifiers. These exchanges are susceptible to eavesdropping which can lead to hacking the smartcard and the theft of its value.
Data encryption can help to reduce the incidence of hacking attacks. However, encryption algorithms can be cracked and are susceptible to unforeseen weaknesses. Moreover, a large body of unencrypted or weakly encrypted smartcards is currently in circulation. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a speech recognition method utilizing the pattern matching method.
In the speech recognition method according to the pattern matching method, the speech information is generally recognized by matching the information of a spectrum obtained from input speech with standard patterns. On the other hand, it has been attempted to positively adopt the information of speech power to improve the recognition accuracy. Recently, a satisfactory result has been reported on a speech recognition of speech patterns made by unspecified talkers (Aikawa, K, et. al.: An Isolated Word Recognition Method Using Power-Weighted Spectral Matching Measure; Transactions of the Committee on Speech Research, Acoust. Soc. Jpn., S81-59 (1981)).
A problem encountered when information of speech power is used to recognize a speech pattern is the difficulty in comparing speech power by use of the absolute values thereof. To solve this problem, it is proposed to normalize the speech power by using the maximum and minimum values of the speech power in the input speech interval, which is also utilized in the method discribed in the above-mentioned report. In this case, relevant processing cannot be initiated until the end of the speech interval because the maximum and minimum values of speech power are needed, that is, the processing cannot be started is principle at the same time when a speech pattern in inputted. This causes the output of the processed recognition results to be delayed, and furthermore, a buffer memory is necessary to store information to be outputted afterward; thus, the size and cost of the speech recognition equipment will be increased.
On the other hand, a pattern matching method according to the dynamic programming (to be abreviated as DP hereinafter) method has been proposed. Especially, a continuous DP matching method has been disclosed as a realtime matching method suitable for continuous speech. (Refer to the Japan Patent Laid-open No. 55-2205 for details.) This method has a feature that the results obtained by matching the input speech with the relevant standard pattern are continuously outputted. However, since the matching results reflect only the evaluation of the average degree of similarity between the input speech and the standard patterns, a problem that the error of recognition therebetween is increased in principle arises for input words including a similar portion. To overcome this difficulty, the inventors of the present invention have proposed a method in which each of the standard patterns is subdivided into a plurality of partial standard patterns and each of these partial standard patterns is compared independently. (See for example, Japan Patent Laid-open No. 58-58598 dated Apr. 7, 1983, only for reference). According to this method, if an input speech is matched with standard patterns and partial patterns thereof under a predetermined condition, the input speech is assumed to fall into the same category as the standard pattern. In this method, however, since each of the standard patterns is matched independently of the partial standard patterns thereof, the standard pattern memory and the load imposed on the matching block are increased. | {
"pile_set_name": "USPTO Backgrounds"
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An organic LED (Light Emitting Diode) element has been widely used for displays, backlights, lighting applications, and the like.
A common organic LED element has a first electrode (anode) placed on a substrate, a second electrode (cathode) and an organic layer placed between the electrodes. When a voltage is applied between the electrodes, holes and electrons are injected from respective electrodes to the organic layer. When the holes and the electrons are recombined in the organic layer, binding energy is generated and an organic light-emitting material in the organic layer is excited by the binding energy. Since light is emitted at the time when the excited light-emitting material is returned to a ground state, a light emitting (LED) element is obtained by utilizing the light emission.
Usually, for the first electrode, i.e., anode, a transparent thin film such as ITO (Indium Tin Oxide) is used and, for the second electrode, i.e., cathode, a metal thin film such as aluminum or silver is used.
Recently, it has been proposed to place a resin-made light scattering layer having scattering materials between an ITO electrode and a substrate (for example, Patent Document 1). In such a constitution, since a part of emitted light generated in the organic layer is scattered by the scattering materials in the light scattering layer, a quantity of light confined in the ITO electrode and substrate (a quantity of totally reflected light) decreases and thus a light extraction efficiency of the organic LED element can be enhanced. | {
"pile_set_name": "USPTO Backgrounds"
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The invention concerns a means for and methods of sealing constructions, in particular earthwork constructions.
Means for and methods of sealing constructions, for example dams and dikes, which use concrete, for example water-impermeable concrete, as a sealing means, are known from the state of the art. The water-impermeable concrete can be introduced into already existing dikes through slot walls or bung bores. That procedure is disadvantageous however precisely in relation to dikes as a rigid body is formed within the dike, which cannot compensate for shifts in the foundation soil so that breaks and cracks can occur in the concrete sealing means. Cracks in the sealing means however mean that the dike or generally the construction becomes water-permeable again and there is the risk of underscouring.
In comparison the use of argillaceous mixtures for sealing constructions, earlier known as ‘puddle’, affords the advantage that this kind of sealing does not form a rigid sealing body so that shifts in foundation soil are compensated and no leaks can occur. Sealing arrangements for constructions comprising argillaceous mixtures involve water-impermeability of approximately the same level as sealing arrangements using concrete. Puddles on the dam outside are also relatively complicated and expensive, require a great deal of construction material, destroy the biotop on the dam surface and do not have particularly long service lives. They are also limited to use in relation to dams or dikes which can be dry at least during the building phase. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a weapon grip including a grip body and a grip shell having an approximately U-shaped cross section and being releasably and replaceably inserted on the grip body. The grip shell is a one-piece component having a rear wall and two side walls formed thereon.
German Offenlegungsschrift (application published without examination) 195 05 829 describes a handgun grip, to the rear side of which a replaceable back part is secured by inserting a lug into a recess of the grip at the upper end of the rear part and inserting a pin through aligned bores in overlapping webs at the lower end of the rear part. By replacing the back part, the grip may be adapted to the hand configuration of the marksman.
U.S. Pat. No. 4,936,036 discloses a handgun grip which is formed of a grip body and a generally U-shaped grip shell which may be releasably inserted on the grip body. The grip shell has a rear wall and two side walls formed thereon to constitute a one-piece component. The grip shell is inserted from behind and is secured by a transverse pin. Such a mode of securement has the disadvantage that it is not play-free.
German Offenlegungsschrift 30 00 017 describes a grip having a grip member which is approximately U-shaped and may be attached to the grip body from behind and may be secured thereto by screws.
U.S. Pat. No. 4,199,887 describes a handgun grip which includes a grip body and a grip shell. The grip shell which has two side walls and a bottom wall connecting the side walls, is inserted from below onto the grip body and is secured by a screw which passes through the bottom wall and is screwed into a yoke. To ensure that the yoke is aligned for allowing the insertion of the screw, the yoke is guided in arcuate grooves provided in the side walls. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a novel derivative of 11-aza-10-deoxo-10-dihydroerythromycin A useful as an antibacterial agent, to intermediates therefor, and to processes for their preparation. More particularly it relates to the N-methyl derivative of 11-aza-10-deoxo-10-dihydroerythromycin A, to pharmaceutically acceptable acid addition salts thereof, and to certain alkanoyl derivatives thereof useful as antibacterial agents, to intermediates therefor, and to processes for their preparation.
Erythromycin A is a macrolide antibiotic produced by fermentation and described in U.S. Pat. No. 2,653,899. Numerous derivatives of erythromycin A have been prepared in efforts to modify its biological and/or pharmacodynamic properties. Erythromycin A esters with mono- and dicarboxylic acids are reported in Antibiotics Annual, 1953-1954, Proc. Symposium Antibiotics (Washington, D.C.), pages 500-513 and 514-521, respectively. U.S. Pat. No. 3,417,077 describes the cyclic carbonate ester of erythromycin A, the reaction product of erythromycin A and ethylene carbonate, as an active and antibacterial agent.
U.S. Pat. No. 4,328,334, issued May 4, 1982, describes 11-aza-10-deoxo-10-dihydroerythromycin A, certain N-acyl- and N-(4-substituted benzenesulfonyl) derivatives thereof having antibacterial properties, and a process for their preparation.
The alkylation of primary and/or secondary amine groups of compounds which include a tertiary amine group is generally complicated. However, it is common practice to protect tertiary amine groups in such compounds by converting them to N-oxides prior to alkylation (Greene, "Protective Groups in Organic Synthesis", John Wiley & Sons, Inc., N.Y., 1981, pg. 281). | {
"pile_set_name": "USPTO Backgrounds"
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The liver is the single organ that is largest in the body and is said to have more than one hundred different kinds of functions including, in addition to metabolism of carbohydrates, lipids, proteins and amino acids, bile production, detoxication, foreign matter treatment, control of hormones, production of prothrombin, one of blood coagulating agents, storage of various constituents of organisms (such as fat, glycogen, proteins, vitamines, etc.) and the like. This organ which has such precise and well-balanced functions possesses a large self-restorative ability and hence is expected to heal spontaneously even if it is functionally disordered. Nevertheless the liver may suffer an acute or chronic lesion due to one or more of various factors such as alcohol, undernutrition, virus infection, medicaments, poisons, biliary obstruction, disorder of the enterohepatic circulatory system and the like and such lesion is manifested as one or more of diseases such as fatty liver, drug-toxic hepatic failure, drug-hypersensitive hepatic failure, alcoholic hepatitis, viral hepatitis, congestive hepatitis, hepatopathy due to biliary engorgement, jaundice, and hepatocirrhosis which is the final picture of the foregoing diseases.
When these hepatic failures are induced, a medication can be employed with the intention of accelerating restoration of cells of the liver parenchyma or alleviating the damage of liver cells with the aid of protection against various hepatopathy-inducing factors, thereby accelerating the recovery from its functional disorder or preventing aggravation.
The inventors have found that paticular cysteine derivatives are effective for the above-mentioned purpose and accomplished the present invention. | {
"pile_set_name": "USPTO Backgrounds"
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Many enterprises employ an interactive voice response (IVR) system that handles calls from telecommunications terminals. An interactive voice response system typically presents a hierarchy of menus to the caller, and prompts the caller for input to navigate the menus and to supply information to the IVR system. For example, a caller might touch the “3” key of his terminal's keypad, or say the word “three”, to choose the third option in a menu. Similarly, a caller might specify his bank account number to the interactive voice response system by inputting the digits via the keypad, or by saying the digits. In many interactive voice response systems the caller can connect to a person in the enterprise by either selecting an appropriate menu option, or by entering the telephone extension associated with that person.
FIG. 1 depicts telecommunications system 100 in accordance with the prior art. Telecommunications system 100 comprises telecommunications network 105, private branch exchange (PBX) 110, and interactive voice response system 120, interconnected as shown.
Telecommunications network 105 is a network such as the Public Switched Telephone Network [PSTN], the Internet, etc. that carries a call from a telecommunications terminal (e.g., a telephone, a personal digital assistant [PDA], etc.) to private branch exchange 110. A call might be a conventional voice telephone call, a text-based instant messaging (IM) session, a Voice over Internet Protocol (VoIP) call, etc.
Private branch exchange (PBX) 110 receives incoming calls from telecommunications network 105 and directs the calls to interactive voice response (IVR) system 120 or to one of a plurality of telecommunications terminals within the enterprise, depending on how private branch exchange 110 is programmed or configured. For example, in an enterprise call center, private branch exchange 110 might comprise logic for routing calls to service agents' terminals based on criteria such as how busy various service agents have been in a recent time interval, the telephone number called, and so forth. In addition, private branch exchange 110 might be programmed or configured so that an incoming call is initially routed to interactive voice response (IVR) system 120, and, based on caller input to IVR system 120, subsequently redirected back to PBX 110 for routing to an appropriate telecommunications terminal within the enterprise. Private branch exchange (PBX) 110 also receives outbound signals from telecommunications terminals within the enterprise and from interactive voice response (IVR) system 120, and transmits the signals on to telecommunications network 105 for delivery to a caller's terminal.
Interactive voice response (IVR) system 120 is a data-processing system that presents one or more menus to a caller and receives caller input (e.g., speech signals, keypad input, etc.), as described above, via private branch exchange 110. Interactive voice response system (IVR) 120 is typically programmable and performs its tasks by executing one or more instances of an IVR system application. An IVR system application typically comprises one or more scripts that specify what speech is generated by interactive voice response system 120, what input to collect from the caller, and what actions to take in response to caller input. For example, an IVR system application might comprise a top-level script that presents a main menu to the caller, and additional scripts that correspond to each of the menu options (e.g., a script for reviewing bank account balances, a script for making a transfer of funds between accounts, etc.).
A popular language for such scripts is the Voice extensible Markup Language (abbreviated VoiceXML or VXML). The Voice extensible Markup Language is an application of the extensible Markup Language, abbreviated XML, which enables the creation of customized tags for defining, transmitting, validating, and interpretation of data between two applications, organizations, etc. The Voice extensible Markup Language enables dialogs that feature synthesized speech, digitized audio, recognition of spoken and keyed input, recording of spoken input, and telephony. A primary objective of VXML is to bring the advantages of web-based development and content delivery to interactive voice response system applications.
FIG. 2 depicts an exemplary Voice extensible Markup Language (VXML) script (also known as a VXML document or page), in accordance with the prior art. The VXML script, when executed by interactive voice response system 120, presents a menu with three options; the first option is for transferring the call to the sales department, the second option is for transferring the call to the marketing department, and the third option is for transferring the call to the customer support department. Audio content (in particular, synthesized speech) that corresponds to text between the <prompt> and </prompt> tags is generated by interactive voice response system 120 and transmitted to the caller.
The VXML script of FIG. 2 also comprises two event handlers. An event can be generated when a caller provides input (e.g., speech, keypad entry, etc.) in response to a prompt from the VXML script, or when there is a prompt timeout (i.e., the caller does not provide any input for a specified time period after a prompt). The first event handler of the VXML script catches and processes events of type telephone.disconnected.hangup, which are generated when a caller hangs up, and the second event handler catches and processes events of type nomatch, which are generated when a caller's input does not match any of a menu's choices.
Another popular standard for IVR system application scripts is Speech Application Language Tags (SALT). FIG. 3 depicts an exemplary XML script of the prior art that contains Speech Application Language Tags (SALT) and provides functionality similar to the VXML script of FIG. 2. | {
"pile_set_name": "USPTO Backgrounds"
} |
Neurogenic inflammation can be triggered by activation of nociceptive and thermal-sensitive nerve endings in tissues. Such activation can be caused by tissue injury, viral infection, or innate conditions, such as autoimmune disease. For example, once an individual has been infected with the herpes virus, the virus will thereafter remain latent in the body. In the latent state, the virus can settle in nerve cell bodies in the ganglia. Stimuli, such as influenza infection, other respiratory disorders, gastrointestinal infections, stress, fatigue, menstruation, pregnancy, allergy, sunlight, or fever, can activate the latent virus, which may then travel from the ganglia to the skin surface and multiply, causing various symptoms. Exemplary symptoms include pain, neurogenic inflammation, blistering, and other somatosensory system manifestations such as, for example, pain, itch, tickle, tingle, and numbness.
At the onset of such symptoms, conventional methods for the treatment of pain and inflammation are often initiated, for example, non-steroidal anti-inflammatory drugs (NSAIDs), antidepressants, and antiviral medications (e.g., acyclovir, famciclovir, or valacyclovir). Such conventional methods often fall short of true treatment by only providing temporary relief, masking symptoms and/or causing serious side effects from prolonged use. Thus, there remains a need for a safe and effective treatment of inflammation and pain which can be used without the side effects associated with long-term use of conventional treatments. | {
"pile_set_name": "USPTO Backgrounds"
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A golf set includes various types of clubs for use in different conditions or circumstances in which a ball is hit during a golf game. A set of clubs typically includes a “driver” for hitting the ball the longest distance on a course. A fairway “wood” can be used for hitting the ball shorter distances than the driver. A set of irons are used for hitting the ball within a range of distances typically shorter than the driver or woods. Every club has an ideal striking location or “sweet spot” that represents the best hitting zone on the face for maximizing the probability of the golfer achieving the best and most predictable shot using the particular club.
An iron has a flat face that normally contacts the ball whenever the ball is being hit with the iron. Irons have angled faces for achieving lofts ranging from about 18 degrees to about 64 degrees. The size of an iron's sweet spot is generally related to the size (i.e., surface area) of the iron's striking face, and iron sets are available with oversize club heads to provide a large sweet spot that is desirable to many golfers. Most golfers strive to make contact with the ball inside the sweet spot to achieve a desired ball speed, distance, and trajectory.
Conventional “blade” type irons have been largely displaced (especially for novice golfers) by so-called “perimeter weighted” irons, which include “cavity-back” and “hollow” iron designs. Cavity-back irons have a cavity directly behind the striking plate, which permits club head mass to be distributed about the perimeter of the striking plate, and such clubs tend to be more forgiving to off-center hits. Hollow irons have features similar to cavity-back irons, but the cavity is enclosed by a rear wall to form a hollow region behind the striking plate. Perimeter weighted, cavity back, and hollow iron designs permit club designers to redistribute club head mass to achieve intended playing characteristics associated with, for example, placement of club head center of mass or a moment of inertia. These designs also permit club designers to provide striking plates that have relatively large face areas that are unsupported by the main body of the golf club head. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of Invention
The invention relates to the field of coded multimedia and its storage and delivery to users, and more particularly to such coding when either the channel and decoding resources may be limited and time varying, or user applications require advanced interaction with coded multimedia objects.
2. Description of Related Art
Digital multimedia offers advantages including manipulation, multigeneration processing, error robustness and others, but incurs constraints due to the storage capacity or transmission bandwidth required, and thus frequently requires compression or coding for practical applications. Further, in the wake of rapid increases in demand for digital multimedia over the Internet and other networks, the need for efficient storage, networked access, search and retrieval, a number of coding schemes, storage formats, retrieval techniques and transmission protocols have evolved. For instance, for image and graphics files, GIF, TIF and other formats have been used. Similarly, audio files have been coded and stored in RealAudio, WAV, MIDI and other formats. Animations and video files have often been stored using GIF89a, Cinepak, Indeo and others.
To play back the plethora of existing formats, decoders and interpreters are often needed and may offer various degrees of speed and quality performance depending on whether these decoders and interpreters are implemented in hardware or in software, and particularly in the case of software, on the capabilities of the host computer. If such content is embedded in web pages accessed via a computer (e.g. a PC), the web browser needs to be set up correctly for all the anticipated content and recognize each type of content and support a mechanism of content handlers (software plugins or hardware) to deal with such content.
The need for interoperability, guaranteed quality and performance and economies of scale in chip design, as well as the cost involved in content generation for a multiplicity of formats has lead to advances in standardization in the areas of multimedia coding, packetization and robust delivery. In particular, ISO MPEG (International Standards Organization Motion Picture Experts Group) has standardized bitstream syntax and decoding semantics for coded multimedia in the form of two standards referred to as MPEG-1 and MPEG-2. MPEG-1 was primarily intended for use on digital storage media (DSM) such as compact disks (CDs), whereas MPEG-2 was primarily intended for use in a broadcast environment (transport stream), although it also supports an MPEG-1 like mechanism for use on DSM (program stream). MPEG-2 also included additional features such as DSM Command and Control for basic user interaction as may be needed for standardized playback of MPEG-2, either standalone or networked.
With the advent of inexpensive boards/PCMCIA cards and with availability of Central Processing Units (CPUs), the MPEG-1 standard is becoming commonly available for playback of movies and games on PCs. The MPEG-2 standard on the other hand, since it addresses relatively higher quality applications, is becoming common for entertainment applications via digital satellite TV, digital cable and Digital Versatile Disk (DVD). Besides the applications and platforms noted, MPEG-1 and MPEG-2 are expected to be utilized in various other configurations, in streams communicated over network and streams stored over hard disks/CDs, as well as in the combination of networked and local access.
The success of MPEG-1 and MPEG-2, the bandwidth limitation of Internet and mobile channels, the flexibility of web-based data access using browsers, and the increasing need for interactive personal communication has opened up new paradigms for multimedia usage and control. In response, ISO-MPEG started work on a new standard, MPEG-4. The MPEG-4 standard has addressed coding of audio-visual information in the form of individual objects and a system for composition and synchronized playback of these objects. While the MPEG-4 development of such a fixed parametric system continues, in the meantime, new paradigms in communication, software and networking such as that offered by the Java language have offered new opportunities for flexibility, adaptivity and user interaction.
For instance, the advent of the Java language offers networking and platform independence critical to downloading and executing of applets (java classes) on a client PC from a web server which hosts the web pages visited by the user. Depending on the design of the applet, either a single access to the data stored on the server may be needed and all the necessary data may be stored on the client PC, or several partial accesses (to reduce storage space and time needed for startup) may be needed. The latter scenario is referred to as streamed playback.
As noted, when coded multimedia is used for Internet and local networked applications on a computer like a PC, a number of situations may arise. First, the bandwidth for networked access of multimedia may be either limited or time-varying, necessitating transmission of the most significant information only and followed by other information as more bandwidth becomes available.
Second, regardless of the bandwidth available, the client side PC on which decoding may have to take place may be limited in CPU and/or memory resources, and furthermore, these resources may be time-varying. Third, a multimedia user (consumer) may require highly interactive nonlinear browsing and playback; this is not unusual, since a lot of textual content on web pages is capable of being browsed using hyperlinked features and the same paradigm is expected for presentations employing coded audio-visual objects. The parametric MPEG-4 system may only be able to deal with the aforementioned situations in a very limited way, such as by dropping objects or temporal occurrences of objects it is incapable of decoding or presenting, resulting in choppy audio-visual presentations. Further, MPEG-4 may not offer any sophisticated control by the user of those kinds of situations. To get around such limitations of the parametric system, one potential option for MPEG-4 development is in a programmatic system.
The use of application programming interfaces (APIs) has been long recognized in the software industry as a means to achieve standardized operations and functions over a number of different types of computer platforms. Typically, although operations can be standardized via definition of the API, the performance of these operations may still differ on various platforms as specific vendors with interest in a specific platform may provide implementations optimized for that platform. In the field of graphics, Virtual Reality Modeling Language (VRML) allows a means of specifying spatial and temporal relationships between objects and description of a scene by use of a scene graph approach. MPEG-4 has used a binary representation (BIFS) of the constructs central to VRML and extended VRML in many ways to handle real-time audio/video data and facial/body animation. To enhance features of VRML and to allow programmatic control, DimensionX has released a set of APIs known as Liquid Reality. Recently, Sun Microsystems has announced an early version of Java3D, an API specification which among other things supports representation of synthetic audiovisual objects as scene graph. Sun Microsystems has also released Java Media Framework Player API, a framework for multimedia playback. However, none of the currently available API packages offer a comprehensive and robust feature set tailed to the demands of MPEG-4 coding and other advanced multimedia content. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to staining techniques for biological specimens which provide for excellent visual clarity and contrast in the stained specimen.
While a variety of stains are available for either light or electron microscopy of glycomacromolecules, such as glycogen, glycoproteins, reticular fibers basement membranes, and nuclear DNA there is a need for a stain that works well for both of the various modes of microscopy.
The use of periodic acid or hydrochloric acid in conjunction with a Schiff reagent are known staining procedure, but does not provide as high a degree of contrast and clarity as one would desire.
Accordingly, it is the primary object of the present invention to provide a procedure for the staining of biological specimens which result in a high degree of visual clarity and contrast in the stained specimen.
This and other objects of the invention will become more apparent from the discussion which follows.
Generally speaking, the present invention provides a procedure for the staining of a biological or other specimen by contacting the specimen sequentially with periodic or hydrochloric acid, thiocarbohydrazide or thiosemicarbazide, and silver methenamine. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to storage containers. More particularly, the present invention relates to proppant discharge systems wherein proppant can be discharged from the storage container. Additionally, the present invention relates to a process for providing proppant to a well site by the transport and delivery of the proppant containers.
2. Description of Related Art
Hydraulic fracturing is the propagation of fractions in a rock layer caused by the presence of pressurized fluid. Hydraulic fractures may form naturally, in the case of veins or dikes, or may be man-made in order to release petroleum, natural gas, coal seam gas, or other substances for extraction. Fracturing is done from a wellbore drilled into reservoir rock formations. The energy from the injection of a highly-pressurized fracking fluid creates new channels in the rock which can increase the extraction rates and ultimate recovery of fossil fuels. The fracture width is typically maintained after the injection by introducing a proppant into the injected fluid. Proppant is a material, such as grains of sand, ceramic, or other particulates, that prevent the fractures from closing when the injection is stopped.
With the rise of hydraulic fracturing over the past decade, there is a steep climb in proppant demand. Global supplies are currently tight. The number of proppant suppliers worldwide has increased since 2000 from a handful to well over fifty sand, ceramic proppant and resin-coat producers.
By the far the dominant proppant is silica sand, made up of ancient weathered quartz, the most common mineral in the Earth's continental crust. Unlike common sand, which often feels gritty when rubbed between the fingers, sand used as a proppant tends to roll to the touch as a result of its round, spherical shape and tightly-graded particle distribution. Sand quality is a function of both deposit and processing. Grain size is critical, as any given proppant must reliably fall within certain mesh ranges, subject to downhole conditions and completion design. Generally, coarser proppant allows the higher now capacity due to the larger pore spaces between grains. However, it may break down or crush more readily under stress due to the relatively fewer grain-to-grain contact points to bear the stress often incurred in deep oil- and gas-bearing formations.
Typically, in any hydraulic fracturing operation, a large amount of such proppant is required. Typically, it has been difficult to effectively store the proppant at the fracturing sites. Additionally, it has been found to be rather difficult to effectively transport the proppant to the desired location. Often, proppant is hauled to the desired locations on the back of trucks and is clumped onsite. Under such circumstances, the proppant is often exposed to adverse weather conditions. This will effectively degrade the quality of the proppant during its storage. Additionally, the maintenance of proppant in containers at the hydraulic fracturing site requires a large capital investment in storage facilities. Typically, the unloading of such storage facilities is carried out on a facility-by-facility basis. As such, there is a need to be able to effectively transport the proppant to and store the proppant in a desired location adjacent to the hydraulic fracturing location.
With the development and acceptance of the well stimulation methodology known as “hydraulic fracturing”, a unique logistics challenge has been created in delivering the massive quantities of proppant from domestic sand mines to the wellhead. This logistics challenge affects every stakeholder up-and-down the logistics chain. In particular, this includes sand mine owners, railroads, trans-loading facilities, oil-field service companies, trucking companies and exploration and production companies. The existing method of delivering sand to the consumer requires the use of expensive specialized equipment and a high level of coordination. This makes the process subject to a myriad of problems that disrupt the efficient flow of proppant to the wellhead. The result of utilizing the current method is the expenditure of hundreds of millions of dollars in largely unnecessary logistics costs.
Sand mines are being rapidly developed all over the United States to satisfy the demand that the “Shale Boom” has created for proppant. Most of the recent mines that have come on-line, or are in varying stages of development, have limited transportation infrastructure to support the export of sand from the sand-pit. As a result, many mines are building rail-spurs that will accommodate up to 100 rail cars or more that can be loaded and stand for transportation to the designated destination. Along with rail-track, these companies are also investing in expensive vertical silo storage facilities to store thousands of tons of proppant. The sand mines are unable to effectively ship proppant to the shale regions without equal fluid trans-loading and storage facilities on the receiving end of the logistics chain. This results in lost revenue and productivity for the mine owner and higher prices for proppant buyers in the destination region.
Railroads are a critical part of the logistics chain required to move proppant from mine to the various shale regions. Due to the lack of rail track and trans-loading facilities in some of these remote regions, the railroad companies must be selective of their customers' delivery locations, and make sure that their customers have the ability to efficiently off-load rail cars. Recently, the railroads have seen the allocated fleet of hopper cars being stranded at those destinations where there is no cost-effective storage option to efficiently off-load those cars. Consequently, there has been a significant opportunity cost that the railroads have been forced to pay. As such, a need has developed for facilitating the ability to quickly and inexpensively off-load proppant from rail cars so as to enable the railroads to improve the velocity, turn-around and revenue-generating capacity of the rail-car fleet.
Limited storage at trans-loading facilities has severely limited many of the current facilities' ability to operate efficiently. Most trans-load facilities are forced to off-load rail hopper cars by bringing in trucks (i.e. pneumatics) along the rail siding, and conveying sand directly from rail to truck. This requires an intense coordination effort on the part of the trans-loader as well as the trucking community. Long truck lines are commonplace, and demurrage fees (i.e. waiting time charged by trucking companies) amount to hundreds of millions of dollars nationwide. As such, the trans-loader is not able to fully realize the utilization of conveying and other material handling equipment. The throughput of these trans-loading terminals severely reduces costing of the terminal meaningful revenue.
Additionally, optimal trans-load terminal locations are immobile and not able to move from one area of the shale pay to another. Investors in immobile silo and flat storage facilities can see the utilization and value of those investments tumble. A potential loss of the investment in such immobile silos can often scare investment capital away from these types of future projects so as to further exacerbate the logistics chain problem. As such, a need has developed for a portable, inexpensive storage and delivery solution for proppant that would help revive the capital needed to improve the facilities and maximize the revenue-generating potential of existing and new trans-load and storage facilities.
The lack of efficient trans-load and storage facilities in shale regions have taken a heavy toll on the efficiencies of trucking fleets. While trucking companies have typically charged demurrage fees to compensate for the waiting time and lost productivity, those types of charges are under significant resistance from the customer base. When trucking companies are required to wait in line to be loaded, or wait at a well-site to be unloaded, the number of turns that the equipment can make in a day is severely limited. Rather than turning two or three loads in a single day, the trucks more typically make one trip per day, and very commonly may make one delivery every two or three days, This lack of efficient fleet utilization results in the trucking, company having to buy more equipment and hire more drivers to move the same amount of material than would be necessary. As such, it would be desirable to eliminate demurrage charges and to present the opportunity for trucking companies to become more profitable while making smaller investments in equipment.
Service companies (such as fracturing companies) are held captive by the current proppant delivery process. This is the result of inefficient trans-load facilities and pneumatic (bulk) truck deliveries. The service company cannot frac a well if it does not have a supply of proppant. It is widely known that the problems surrounding the efficient delivery of proppant to the well-site is one of the primary challenges to the service companies in successfully completing a frac job. Pressure pumps, coiled tubing and other well stimulation equipment, often site idle due to the lack of required proppant at the well-site, “Screening-Out” or running out of proppant is very common at well locations due to the lack of control over what is happening up-stream in the proppant logistics chain. This results in lower profit margins to the service company. Many small to medium-sized hydraulic fracturing companies have little or no logistics infrastructure. Some have entered the marketplace without much thought to the logistics problems associated with taking delivery of the necessary supplies to complete a well. In doing so, many of these companies have been forced to source material and employ very expensive logistics options in order to survive. This has resulted in above-market pricing in order to complete wells. There is also as risk of losing out on otherwise viable hydraulic fracturing contracts. As such, there is a need to lower costs across the board in order to properly compete.
Exploration and production companies, along with the entire U.S. population, pay the ultimate bill for all of the inefficiencies and waste that plagues the proppant supply chain Service companies are forced to price hydraulic fracturing services by taking into account the historical costs of supply chain problems. Exploration and production companies need to pass on the overall increased cost of production. As such, there is a need to provide a cost-effective solution to improve the profitability of stake holders in the proppant logistics chain, while lowering the overall cost to the consumer.
U.S. patent application Ser. No. 13/427,140, filed on Mar. 22, 2012 by the present inventor, describes a system for the delivery of proppant between a loading station and the well site. This application describes the steps of placing the storage container in a location adjacent to a train site such that the proppant, as delivered by the train, can be discharged into the container. The container can then be transported for storage in stacks at the loading area or can be delivered to a tilting mechanism at the loading station. The tilting station will tilt the container so as to allow the proppant to flow outwardly therefrom. This proppant will flow, by a conveyor, to a pneumatic truck. The truck can then transport the proppant over the highways to the well site. At the well site, the proppant from the pneumatic truck can then be discharged into a twenty foot container at the well site. These twenty foot containers can be stored at the well site in a stacked configuration. Ultimately, each of the containers can be transported to another tilting mechanism at the well site so that the proppant within each of the storage containers can be discharged onto a conveyor and ultimately for use during the fracturing operation.
In this U.S. patent application Ser. No. 13/427,140, the twenty-foot ISO container that is utilized is one of the most inexpensive and readily-available pieces of transportation equipment in the world. It was determined that the use of the twenty-foot container allows for the transportation of proppant through various minor modifications to the internal walls and reinforcements of the twenty-foot ISO container. The available capacity is more than acceptable. It was determined that this modified twenty-foot container could hold in excess of forty-five tons of proppant. The cost of an unmodified twenty-foot ISO container is less than four thousand dollars. This makes it very affordable compared to the cost of building, vertical silos or flat storage buildings.
The twenty-foot ISO container was modified by cutting a hole in the top of the container and constructing a water-tight, hinged hatch through which the proppant could be poured by any number of readily-available conveying units. There was also a lower hatch in the twenty-foot ISO container. This lower hatch could be opened to drain the proppant out of the twenty-foot ISO container. Alternatively, a square flow-gate was fabricated and welded to the vertical rear lower side of the twenty-foot container. This gate hatch allowed the container to be tilted in the manner of a dump truck bed. As a result, sand could flow out of the flow gate while moderating the flow of the sand.
This patent application provided the ability to trans-load sand via containers from a standard rail hopper car to the twenty-foot ISO container. It was determined that the container could be loaded in less than twenty minutes with at least fort-five tons of proppant. By pre-positioning the container along, the rail track, movable conveyors could work the train from one end to the other and unload the train in a very efficient and timely manner. This part of the process eliminated the coordination efforts of calling in pneumatic trucks that could be systematically loaded by conveying units. This reduced the time necessary to unload a train's hopper cars by many hours. It also eliminated truck traffic and demurrage charges at the rail-spur and trans-load facility.
Once the proppant is loaded into the container, another piece of specialized equipment would be used to lift the full container and to stack the container upon other containers. The stackable arrangement of containers allows the ability to operate and store proppant within a very small footprint. The specialized equipment that was required to lift the full containers was so heavy and large that it would have to be disassembled into several pieces before moving from one location to another. This created some limitations on the flexibility that such equipment lent to the containerized process.
By “containerizing” proppant, it was found that an inventory management system could be added in order to provide real-time, accurate information pertaining to the volume/inventory of proppant that the customers own in a particular region. Currently, many proppant buyers are subject to inaccurate volume reporting from trans-loading facilities. As such, they May not be certain that the proppant being delivered to the well-site is, in fact, of the quality and grade that they have purchased. By applying an inventory management system, bar coding, and scanning the containers into and out of inventory, the customers would be assured that they have received, their proppant and would be able streamline the procurement process when ordering more material.
In this prior process, since the twenty-foot ISO container needed to be emptied and trans-loaded into pneumatic trailers for delivery to the wellhead, a tilting unit was incorporated into the process. This tilting unit accepted the twenty-foot ISO containers. The tilting unit is able to lift one end of the container and create the required angle to wholly empty the container through the flow gate. Once tilted, the sand would spill onto the belt of the conveyor and rise vertically into a hopper. The hopper rested on a steel fabrication stand. This stand is high enough such that a truck that pulls a pneumatic trailer could drive under the stand and be gravity fed by the hopper so as to fill up the sand trailer. These “loading stations” could be replicated along a path so as to alleviate the bottleneck of trucks at a trans-load facility that has a limited number of conveyors available to load the trucks. Once again, trucking demurrage at this trans-load facility could be dramatically reduced through the process. The railcars can be off-loaded rapidly and released back to the railroads. This also reduced or eliminated demurrage fees charged by the railroads for rail hopper cars that stood waiting to be off-loaded.
This prior process created an inexpensive storage solution, improved the efficiencies of the trans-loading process, added inventory visibility and controls, and reduced both truck and rail demurrage charges. However, it did have several limitations. For example, the twenty-foot ISO container, while capable of handling ninety thousand pounds of proppant, could not be transported legally over a public road. In most states, the maximum allowable total weight of a vehicle and its payload is eighty thousand pounds of gross vehicle weight in order to be considered a legal load. By law, any load that can be broken down by two units or more, in order to achieve a legal weight limit, must be divided into multiple loads. Since proppant is divisible, the law does not allow for heavy or over-weight loads.
The angle of repose of a granular material is the steepest angle of descent or dip of the slope relative to the horizontal plane when material on the slope face is on the verge of sliding. When bulk granular materials are poured onto a horizontal surface, a conical pile will form. The internal angle between the surface of the pile and the horizontal surface is known as the angle of repose and is related to the density, surface area and shape of the particles, and the coefficient of friction of the material. The angle of repose is also gravity-dependent.
When analyzing the angle of repose of proppant poured into a twenty-foot ISO container, it was evident that much of the volume of such a container was void. Specifically, the upper ends of twenty-foot ISO container could not be utilized without somehow manipulating or tilting the container as it was filled by a conveyor. Moreover, when emptying the container, by way of the original bottom hatch, the proppant would pour directly out of the bottom and leave a significant amount of material sitting on the floor of the container.
U.S. patent application Ser. No. 13/555,635, filed on Jul. 23, 2012 by the present inventor, is the parent of the present application. U.S. patent application Ser. No. 13/555,635 described a new generation of the container by taking the original twenty-foot ISO container and splitting it in half. As such, a ten foot ISO container was provided. By breaking the container into a ten foot configuration, it was determined that such a container could hold approximately 45,000-48,000 pounds of proppant. The total gross vehicle weight of such a fully-loaded container could be legally transported over a public road. This was a major breakthrough. The container could be delivered to the wellhead in advance of a frac crew and eliminate sand deliveries during the fracturing process. Because all of the required proppant for any frac job could be delivered and stored on-site, such a ten-foot ISO container effectively eliminated the occurrence of trucking demurrage charges at the well-site. Also, the use of such a ten-foot container effectively eliminated the problems caused by the angle of repose of the proppant and allowed the volumetric capacity of such a ten-foot ISO container to be more fully utilized. It was found to be the optimal configuration, size, and cost for the process.
This prior application utilized an insert that is fabricated, and welded within the interior of the ten-foot ISO container. The insert allowed, the proppant, loaded through the top hatch, to fully flow out of a newly designed bottom flow-gate. The need to manipulate or tilt the container was eliminated. This ten-foot container could now be filled and emptied by using only gravity to do so.
In the past, various patents have issued relating to storage and transport facilities. For example, U.S. Patent Publication No. 2008/0179054, published on Jul. 31, 2008 to McGough et al., shows a bulk material storage and transportation system. In particular, the storage system is mounted on the trailer of a truck. The storage system includes walls that define an interior volume suitable for receiving the aggregate material therein. There are hoppers provided at the bottom of the container. These hoppers have inclined walls. The hoppers can extend so as to allow the material from the inside of the container to be properly conveyed to a location exterior of the container. Actuators are used so as to expand and collapse the container.
U.S. Pat. No. 7,240,681, issued on Jul. 10, 2007 to L. Saik, describes a trailer-mounted mobile apparatus for dewatering and recovering formation sand. The trailer is mounted to a truck-towable trailer so as to receive sand therein. The container has a pair of sloping end walls. The back end of the container is suitably openable so as to allow the sand to be removed therefrom. A pneumatic or hydraulic ram is provided on the forward part of the container so as to allow the container to be lifted angularly upwardly so as to allow sand to be discharged through the gate at the rear of the container.
U.S. Pat. No. 4,247,228, issued on Jan. 27, 1981 to Gray et al., describes a dump truck or trailer with a pneumatic conveyor. The container is mounted to a frame on wheels. A hydraulic ram tilts the container for dumping through a rear outlet. A pneumatic conveyor is carried by the frame with an intake at the rear of the container. A gate allows the solids to be dumped conventionally by gravity or to be blown to a storage facility by the pneumatic container. The container has a top hatch formed therein so as to allow the solids to be introduced into the interior of the container.
U.S. Pat. No. 2,865,521, issued on Dec. 23, 1958 to Fisher et al., shows a bulk material truck that has an interior volume suitable for the receipt of bulk material therein. A pneumatic conveyer is utilized so as to allow the removal of such material from the bottom of the container. A pair of sloping walls are provided on opposite sides of the container so as to allow the bulk material within the container to be passed toward the bottom of the container. A top hatch is provided on the top of the conveyer. The pneumatic conveyer is connected to the bottom of the container.
It is an object of the present invention to provide a proppant storage container that allows proppant to be easily transported and stored.
It is another object of the present invention to provide a proppant storage container that allows the proppant to be easily and efficiently discharged to the bottom of the container.
It is another object of the present invention to provide a proppant storage container which allows for the effective storage of proppant at the fracturing site.
It is another object of the present invention to provide a process for delivering proppants that eliminates the use of pneumatic trailers.
It is further object of the present invention to provide a proppant storage container and a process for delivering proppant in which of the containers can be moved by a simple forklift.
It is another object of the present invention to provide a process for delivering proppants which effectively eliminates demurrage associated with the loading station and at the well site.
It is a further object of the present invention to provide a process of the deliver proppant which avoids the degradation of the proppant as a result of repeated handling.
It is a further object of the present invention to provide a proppant discharge system which provides a premeasured amount of proppant to the drill site.
it is still another object of the present invention to provide a proppant container which satisfies highway regulation and which has less void space within the interior of the container.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims. | {
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Known kneading machines for both domestic and industrial use comprise a container, which is typically made of stainless steel, wherein a rotor provided with a plurality of mixing paddles is arranged; the rotor is rotatably restrained to the shaft of an electric motor.
In order to make an alimentary dough, a certain amount of ingredients in the solid state, such as mixtures of flour and/or meals, is introduced in the container, wherein they are mixed in a continuous manner by rotating the rotor during the preparation of the dough. In the case of the preparation of alimentary doughs for bread or pastry products, the ingredients in the solid state also comprise yeast.
During the mixing step the container is generally closed by a lid and ingredients in the liquid, e.g. water, solid and/or powdered state necessary to the preparation of the desired dough are gradually added to the ingredients in the solid state. The mixing step continues until a smooth dough suitable to be subjected to further processing is obtained.
The European patent EP 2554051 in the applicant's name describes for example a kneading machine for alimentary doughs comprising a container provided with a tight lid and a rotor arranged proximate to or at the bottom of the container and rotatably restrained about a vertical rotation axis. The kneading machine also comprises a plurality of spray nozzles restrained to the lid, which are arranged and oriented so as to direct their jets towards the bottom and the peripheral walls of the container. The rotor comprises a flat base formed of a plurality of arms and a plurality of mixing paddles extending from the arms predominantly perpendicular thereto. The free ends of the paddles are bent towards the rotation axis of the rotor and inclined relative to its flat base, as well as relative to a plane perpendicular thereto and passing through the rotation axis. Thanks to these characteristics, it is possible to generate swirling mixing movements on planes that are perpendicular to each other, thus promoting mixing of the particles of the mixtures of flours and/or meals with the ingredients injected by the nozzles, and hence enhancing homogenization and hydration of the dough.
Once the preparation step is finished an alimentary dough must be discharged from the container of a kneading machine in order to proceed to further steps and/or processing of the production process. At an industrial level this operation is carried out in an automated way.
It is known that a finished alimentary dough has a remarkable compactness and a generally sticky consistency, thereby making it difficult to discharge it from the container of a kneading machine. While in kneading machines wherein the rotor is rotatably arranged about an horizontal axis the rotor can be removed before discharging the dough, in kneading machines having a vertical axis as the kneading machine of the
European patent EP 2554051 this is not possible because the rotor is under the dough relative to the discharging direction.
Consequently, dough residues often remain inside the container of a kneading machine with a vertical rotation axis, which require cleaning operations after discharging of the dough before proceeding to a new preparation step. | {
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Luminaires for providing general illumination to an area are well known and often used in outdoor lighting applications including roadway and sidewalk lighting, parking lot lighting, and residential area lighting. In order to increase luminaire efficiency, light emitting diodes have been incorporated into luminaire designs as a light source. Light emitting diodes offer several advantages including high lighting efficiency, long lifetimes that can exceed 50,000 hours of operation, resistance to physical or mechanical shock and rapid lighting response time.
Conversely, light emitting diodes additionally exhibit several disadvantages which challenge their use in luminaire constructions, including luminaires used for general outdoor illumination. The performance of a light emitting diode, for example, is largely dependent on the temperature of the operating environment. Operating a light emitting diode in high ambient temperatures can lead to overheating and device failure. Moreover, light emitting diodes are generally offered in relatively low lumen packages, necessitating large numbers to create the required lighting levels. As a result, it is difficult to produce a light emitting diode luminaire having the size, shape and light output of existing high intensity discharge (HID) luminaires. | {
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Conventional microelectronics fabrication techniques often involve the fabrication of devices, for example microprocessors, on a semiconductor substrate by the selective doping of regions of the substrate and deposition and patterning of various layers of dielectric, metals, and semiconductor materials. These layers of materials are often very thin, on the order of microns. The resulting devices are effectively two dimensional. Providing additional functionality, for example, by the addition of additional transistors or other features to a device, conventionally requires the surface area of the device to be increased, subsequently reducing the number of devices that can be formed on a single wafer or included within a package of a given size. | {
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Phase-locked loop (PLL) circuits are useful in many electronic systems. For example, PLL circuits may be used for master clock generation for a microprocessor system, clock generation for a sampling clock in an analog-to-digital conversion system, clock generation for data recovery in a low-voltage differential signal (LVDS) driver/receiver system, cathode ray tube (CRT) displays, as well as numerous other applications.
PLL applications typically provide an output clock signal by comparing the output clock signal to a reference clock signal. A phase-frequency detector (PFD) circuit is often employed to provide a raw control signal to a loop filter. The phase-frequency detector circuit provides the raw control signal in response to comparing the phase and frequency of the output clock signal to the reference clock signal. The loop filter often is a low-pass filter (LPF) that is arranged to provide a smoothed or averaged control signal in response to raw control signal. Typically, a voltage-controlled oscillator (VCO) is arranged to receive the control signal from the loop filter. The VCO produces the clock signal in response to the control signal such that the frequency of the clock is varied until the phase and frequency of the clock signal are matched to the reference clock signal.
A PLL circuit may include a PFD circuit that provides UP and DOWN signals in response to the comparison between the output clock signal and the reference clock signal. The UP and DOWN signals are dependent on both the phase and frequency of the output and reference clock signals. The UP signal is active when the frequency of the output clock signal is lower than the reference signal, while the DOWN signal is active when the frequency of the output clock signal is determined to be higher than the reference signal. Similarly, the UP signal is active when the phase of the output clock is lagging behind the phase of the reference clock, and the DOWN signal is active when the phase of the output clock is leading the phase of the reference clock. | {
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The invention relates to a method for distributing audiovisual sequences.
In order to protect an audiovisual sequence against hacking, it is known to tattoo the audiovisual sequence in a visible or invisible way, so as to identify the holder of a pirated copy. It is also known to encipher the audiovisual sequence during a transmission in order to prevent the illegal playing of the sequence. Of course, it is possible to combine the two protection methods by enciphering the audiovisual sequence at the level of an enciphering module on the transmitting side and by tattooing the sequence after the deciphering at the level of a tattooing module on the receiving side. However, such a method would not prevent a fraudor from retrieving the sequence at the output of the deciphering module prior to the passage thereof at the tattooing module. Such a fraudor could then freely use the non tattooed audiovisual sequence if he or she could decipher the sequence.
In order to solve this general problem, a method is known for distributing a marked audiovisual sequence from a nominal audiovisual sequence to a receiving item of equipment, said nominal audiovisual sequence having a nominal content, the method including steps wherein: a first modified flow having a modified content different from the nominal content is generated, and a second marked complementary flow including marked complementary digital information is generated; said first modified flow and said marked complementary information are transmitted to the receiving item of equipment so as to allow the restoration of said marked audiovisual sequence at the receiving item of equipment.
Such a method is known from the application WO 2004/062281. In one embodiment of this application, the complementary flow includes marking instructions intended to insert an invisible and customized mark into the marked audiovisual sequence. In a preferred embodiment of the application WO 2004/062281, these instructions more particularly make it possible to reverse the LSB of some visual coefficients, such as the DC coefficients. The absence or not of a reversion on an LSB will make it possible to determine the first mark inserted into the audiovisual sequence during an identification step. With such instructions being inserted into the complementary flow, a fraudor could not have access to the audiovisual content prior to the application of the marking instructions and thus prior to the insertion of the first customized mark.
However, this type of method cannot be used in combination with known tattooing or marking devices. As a matter of fact, in the above-mentioned application, the elements contained in the marked complementary information enabling the marking of said audiovisual sequence contain instructions which are specific to the marking operation: reversion of the LSB of some visual coefficients. Marking instructions are thus predefined so that it is not possible to mark the audiovisual sequence using a standard marking device thus generating a priori unknown marking information.
Following the above-mentioned document, a problem that the invention intends to solve is thus to facilitate the marking of the audiovisual sequence. Another problem which the invention intends to remedy consists in allowing the marking of an audiovisual sequence while allowing the utilization of any type of marking device or without knowing the marking information beforehand. Such problems are solved by the invention which relates to a method such as described hereabove, wherein the step during which the second mark complementary flow is generated, includes steps wherein: an operation of marking of said nominal audiovisual sequence is carried out so as to determine a marked audiovisual sequence having a marked content; a difference between the marked content, on the one hand, and said modified content or said nominal content, on the other hand, is determined; said marked complementary digital information depending on said difference.
Thus, according to the invention, using the difference between, on the one hand, the marked content and the modified content or the nominal content, on the other hand, it is possible to determine what mark has been applied to the nominal audiovisual sequence during the marking operation, while transmitting data enabling the restoration of the marked audiovisual sequence in a secure way. Thus, it is possible to transmit one securely marked audiovisual sequence without knowing a priori the marking information and thus from any tattooing device.
According to one embodiment of the invention, the step consisting in determining a difference between said nominal content and said modified content includes steps wherein: a second modified complementary flow comprising complementary digital information capable of allowing the restoration of the nominal content from the modified content is generated, at least a piece of marking information is determined as a function of the bit differences between the marked content and the nominal content; said marked complementary digital information are determined as a function of said complementary information and said marking information.This embodiment has the advantage of being implemented on a known protection module. In this embodiment, said marking information, said complementary information and said marked complementary information can have an identical format. This more particularly makes it possible to make the transmission method even safer.
Besides, in one embodiment, the step consisting in generating said second marked complementary flow includes steps wherein: a second modified complementary flow comprising complementary digital information capable of allowing the restoration of the nominal content from the modified content is generated, marking information are determined so as to enable the restoration of said marked audiovisual sequence from said nominal audiovisual sequence, said marking information being determined further to the operation of marking said nominal audiovisual sequence; said marked complementary digital information are determined as a function of said complementary information and said marking information, wherein said marking information, said complementary information and said marked complementary information have an identical format.According to another embodiment of the invention, the step consisting in determining a difference between said marked content and said modified content includes steps wherein: said marked content and said modified content are compared at the bit level so as to determine said difference.This more particularly makes it possible to easily obtain the difference between the marked content and the modified content.
In order to obtain a marked audiovisual sequence which is also customized, said marked complementary information may include a customization identifier. This customization identifier can include a single identifier of said receiving item of equipment and/or a single identifier of a user of said receiving item of equipment, and/or a single identifier of said marking operation. This makes it a customization of the marked content possible as a function of the selected identifier and by possibly using an identifier database. The marking according to the invention can thus include a tattooing and a customization.
In order to improve the protection of the audiovisual sequence against possible fraudors, said marked complementary digital information can include information relating to digital rights associated with the nominal audiovisual sequence. Said marked complementary information include a tattoo so that said marked content is visually and aurally identical to the nominal content, so that possible fraudors will not be able to detect the marking and so that an authorized user will not be disturbed in the consumption of said marked audiovisual sequence. Said nominal audiovisual sequence has a nominal format wherein said modified content has a format identical with said nominal format, so that a user can have access to some information of the nominal audiovisual sequence without being able to consume this sequence in a satisfactory way without a particular authorization.
The invention also relates to a system for distributing a marked audiovisual sequence from a nominal audiovisual sequence to a receiving item of equipment, said nominal audiovisual sequence having a nominal content,
the system including:
means capable of generating a first modified flow having a modified content different from the nominal content, and means capable of generating a second marked complementary flow including marked complementary digital information; means capable of transmitting to the receiving item of equipment said first modified flow and the marked complementary information, so as to allow the restoration of said marked audiovisual sequence at the level of the receiving item of equipment;the system being characterised in that the means for generating a second marked complementary flow include: means capable of carrying out an operation of marking said nominal audiovisual sequence so as to determine the marked audiovisual sequence having a marked content; means capable of determining a difference between, on the one hand, said marked content and on the other hand, said modified content or said nominal content; means capable of generating said marked complementary digital information as a function of said difference.
In the Figures, identical references refer to similar technical elements except otherwise indicated hereinunder. | {
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The invention relates in general to hypodermic syringes for medical injection and more particularly to syringes which are limited to a single use, thereby preventing the spread of disease by drug offenders, and others, through the sharing of syringes. The invention relates also to devices for the protection of medical workers, and others, from accidental syringe needle scratches. | {
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Electronic systems and industrial electronics, especially compute systems, control systems, and devices such as cellular phones, navigations systems, portable digital assistants, and combinations of systems and devices, are providing increasing levels of functionality to support demands of modern life. Efficient and expedient access to data of storage devices by the systems and devices continually grow as research and development in the existing technologies take a myriad of different directions.
The increasing demand for efficient and expedient access to storage devices in modern life requires the combinations of systems and devices to access information at any time, while data rates continue to increase and data latencies continue to decrease. Interface between host systems and storage devices are not efficient.
Thus, a need still remains for an electronic system to provide an improved and more efficient messaging capability with storage devices. In view of the ever-increasing commercial competitive pressures, along with growing consumer expectations and the diminishing opportunities for meaningful product differentiation in the marketplace, it is increasingly critical that answers be found to these problems. Additionally, the need to reduce costs, improve efficiencies and performance, and to meet competitive market pressures, adds an even greater urgency to the critical necessity for finding answers to these problems.
Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art. | {
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Active ingredients, such as drugs or pharmaceuticals, may be prepared in a tablet form to allow for accurate and consistent dosing. However, this form of preparing and dispensing medications has many disadvantages including that a large proportion of adjuvants that must be added to obtain a size able to be handled, that a larger medication form requires additional storage space, and that dispensing includes counting the tablets which has a tendency for inaccuracy. In addition, many persons, estimated to be as much as 28% of the population, have difficulty swallowing tablets. While tablets may be broken into smaller pieces or even crushed as a means of overcoming swallowing difficulties, this is not a suitable solution for many tablet or pill forms. For example, crushing or destroying the tablet or pill form to facilitate ingestion, alone or in admixture with food, may also destroy the controlled release properties.
As an alternative to tablets and pills, films may be used to carry active ingredients such as drugs, pharmaceuticals, and the like. However, historically films and the process of making drug delivery systems therefrom have suffered from a number of unfavorable characteristics that have not allowed them to be used in practice.
Films that incorporate a pharmaceutically active ingredient are disclosed in expired U.S. Pat. No. 4,136,145 to Fuchs, et al. (“Fuchs”). These films may be formed into a sheet, dried and then cut into individual doses. The Fuchs disclosure alleges the fabrication of a uniform film, which includes the combination of water-soluble polymers, surfactants, flavors, sweeteners, plasticizers and drugs. These allegedly flexible films are disclosed as being useful for oral, topical or enteral use. Examples of specific uses disclosed by Fuchs include application of the films to mucosal membrane areas of the body, including the mouth, rectal, vaginal, nasal and ear areas.
Examination of films made in accordance with the process disclosed in Fuchs, however, reveals that such films suffer from the aggregation or conglomeration of particles, i.e., self-aggregation, making them inherently non-uniform. This result can be attributed to Fuchs' process parameters, which although not disclosed likely include the use of relatively long drying times, thereby facilitating intermolecular attractive forces, convection forces, air flow and the like to form such agglomeration.
The formation of agglomerates randomly distributes the film components and any active present as well. When large dosages are involved, a small change in the dimensions of the film would lead to a large difference in the amount of active per film. If such films were to include low dosages of active, it is possible that portions of the film may be substantially devoid of any active. Since sheets of film are usually cut into unit doses, certain doses may therefore be devoid of or contain an insufficient amount of active for the recommended treatment. Failure to achieve a high degree of accuracy with respect to the amount of active ingredient in the cut film can be harmful to the patient. For this reason, dosage forms formed by processes such as Fuchs, would not likely meet the stringent standards of governmental or regulatory agencies, such as the U.S. Federal Drug Administration (“FDA”), relating to the variation of active in dosage forms. Currently, as required by various world regulatory authorities, dosage forms may not vary more than 10% in the amount of active present. When applied to dosage units based on films, this virtually mandates that uniformity in the film be present.
The problems of self-aggregation leading to non-uniformity of a film were addressed in U.S. Pat. No. 4,849,246 to Schmidt (“Schmidt”). Schmidt specifically pointed out that the methods disclosed by Fuchs did not provide a uniform film and recognized that that the creation of a non-uniform film necessarily prevents accurate dosing, which as discussed above is especially important in the pharmaceutical area. Schmidt abandoned the idea that a mono-layer film, such as described by Fuchs, may provide an accurate dosage form and instead attempted to solve this problem by forming a multi-layered film. Moreover, his process is a multi-step process that adds expense and complexity and is not practical for commercial use.
Other U.S. Patents directly addressed the problems of particle self-aggregation and non-uniformity inherent in conventional film forming techniques. In one attempt to overcome non-uniformity, U.S. Pat. No. 5,629,003 to Horstmann et al. and U.S. Pat. No. 5,948,430 to Zerbe et al. incorporated additional ingredients, i.e. gel formers and polyhydric alcohols respectively, to increase the viscosity of the film prior to drying in an effort to reduce aggregation of the components in the film. These methods have the disadvantage of requiring additional components, which translates to additional cost and manufacturing steps. Furthermore, both methods employ the use the conventional time-consuming drying methods such as a high-temperature air-bath using a drying oven, drying tunnel, vacuum drier, or other such drying equipment. The long length of drying time aids in promoting the aggregation of the active and other adjuvant, notwithstanding the use of viscosity modifiers. Such processes also run the risk of exposing the active, i.e., a drug, or vitamin C, or other components to prolonged exposure to moisture and elevated temperatures, which may render it ineffective or even harmful.
In addition to the concerns associated with degradation of an active during extended exposure to moisture, the conventional drying methods themselves are unable to provide uniform films. The length of heat exposure during conventional processing, often referred to as the “heat history”, and the manner in which such heat is applied, have a direct effect on the formation and morphology of the resultant film product. Uniformity is particularly difficult to achieve via conventional drying methods where a relatively thicker film, which is well-suited for the incorporation of a drug active, is desired. Thicker uniform films are more difficult to achieve because the surfaces of the film and the inner portions of the film do not experience the same external conditions simultaneously during drying. Thus, observation of relatively thick films made from such conventional processing shows a non-uniform structure caused by convection and intermolecular forces and requires greater than 10% moisture to remain flexible. The amount of free moisture can often interfere over time with the drug leading to potency issues and therefore inconsistency in the final product.
Conventional drying methods generally include the use of forced hot air using a drying oven, drying tunnel, and the like. The difficulty in achieving a uniform film is directly related to the rheological properties and the process of water evaporation in the film-forming composition. When the surface of an aqueous polymer solution is contacted with a high temperature air current, such as a film-forming composition passing through a hot air oven, the surface water is immediately evaporated forming a polymer film or skin on the surface. This seals the remainder of the aqueous film-forming composition beneath the surface, forming a barrier through which the remaining water must force itself as it is evaporated in order to achieve a dried film. As the temperature outside the film continues to increase, water vapor pressure builds up under the surface of the film, stretching the surface of the film, and ultimately ripping the film surface open allowing the water vapor to escape. As soon as the water vapor has escaped, the polymer film surface reforms, and this process is repeated, until the film is completely dried. The result of the repeated destruction and reformation of the film surface is observed as a “ripple effect” which produces an uneven, and therefore non-uniform film. Frequently, depending on the polymer, a surface will seal so tightly that the remaining water is difficult to remove, leading to very long drying times, higher temperatures, and higher energy costs.
Other factors, such as mixing techniques, also play a role in the manufacture of a pharmaceutical film suitable for commercialization and regulatory approval. Air can be trapped in the composition during the mixing process or later during the film making process, which can leave voids in the film product as the moisture evaporates during the drying stage. The film frequently collapse around the voids resulting in an uneven film surface and therefore, non-uniformity of the final film product. Uniformity is still affected even if the voids in the film caused by air bubbles do not collapse. This situation also provides a non-uniform film in that the spaces, which are not uniformly distributed, are occupying area that would otherwise be occupied by the film composition. None of the above-mentioned patents either addresses or proposes a solution to the problems caused by air that has been introduced to the film.
Therefore, there is a need for methods and compositions for film products, which use a minimal number of materials or components, and which provide a substantially non-self-aggregating uniform heterogeneity throughout the area of the films. Desirably, such films are produced through a selection of a polymer or combination of polymers that will provide a desired viscosity, a film-forming process such as reverse roll coating, and a controlled, and desirably rapid, drying process which serves to maintain the uniform distribution of non-self-aggregated components without the necessary addition of gel formers or polyhydric alcohols and the like which appear to be required in the products and for the processes of prior patents, such as the aforementioned Horstmann and Zerbe patents. Desirably, the films will also incorporate compositions and methods of manufacture that substantially reduce or eliminate air in the film, thereby promoting uniformity in the final film product. | {
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VECSELs typically comprise a first end mirror and an active region formed in a layer sequence, and a second end mirror arranged separated from the layer sequence and forming an external cavity of the laser. In standard setups the external cavity is composed of macroscopic optical elements, which are very bulky and need involved adjustment. By realizing the external optical components from a wafer and bonding this wafer to the wafer carrying the layer sequence, which is typically a GaAs wafer, it is possible to manufacture many thousands of micro-VECSELs in parallel and test them directly on the wafer like VCSELs (vertical cavity surface emitting laser diodes).
Known optically-pumped VECSELs need separated mounting and alignment of the pump lasers to the resonator or cavity of the VECSEL. This requires time-consuming production and bulky modules.
US 20100014547 A1 discloses a device for longitudinal pumping of a solid state laser medium. This device comprises several pump laser diodes which are mounted on side faces of a cooling device of the laser medium. The pump radiation emitted by the laser diodes is reflected by several parabolic mirrors toward one of the end faces of the solid state laser medium. In this device the several parabolic mirrors have to be precisely aligned in order to achieve the desired intensity distribution of the pump radiation at the entrance of the solid state laser medium. | {
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Generally, there has been an increasing need for effective separation, alignment, and manipulations of colloidal and cellular suspensions or droplets and other particles based on the increasing number of systems utilizing microscale transport properties. These types of systems have significant parallelization and high throughput. Examples of applications for these systems include genetic analysis, molecular separations, sensors, imaging, printing, and surface patterning.
In one example, manipulation and positioning of the colloidal and cellular suspensions or droplets, and other particles is useful if imaging of the particles is desired. For example, the use of fluorescence detection is a ubiquitous practice in microbiology and biochemistry as well as colloidal science, biophysics and several other disciplines. Labeling cells, cellular components or individual biomolecules, or particles with molecular or colloidal fluorescent probes has enabled the visualization of several cellular metabolic and bio-molecular assembly processes. As such, methods involving fluorescent tagging, excitation, and detection may rely on methods of aligning, sorting, and manipulations.
An example of a known separation system is a fluorescence activated cell sorting (FACS) system that sorts and manipulates cells in continuous microfluidic flows. Fluorescence labeling of cells combined with traditional macroscopic FACS systems allow for the identification and separation of rare cells from concentrated suspensions, the sequestration of cells displaying desired physiological properties or metabolic states, and the parsing of large combinatorial libraries for specific information. A FACS system, however, can be complex and cumbersome. Furthermore, FACS, as well as other known alignment and sorting methods, may be improved by simplifying signal acquisition and interpretation to allow for closer to real-time feedback. | {
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a. Field of the Invention
The instant invention relates to catheters. In particular, the instant invention relates to a catheter with a steerable distal section having reduced variation in planarity during deflection.
b. Background Art
It is well-known that the pumping action of the heart is controlled by electrical stimulation of myocardial tissue. Stimulation of this tissue in various regions of the heart is controlled by a series of conduction pathways contained within the myocardial tissue.
Cardiac arrhythmias arise when the pattern of the heartbeat is changed by abnormal impulse initiation or conduction in the myocardial tissue. Such disturbances often arise from additional conduction pathways which are present within the heart either from a congenital developmental abnormality or an acquired abnormality which changes the structure of the cardiac tissue, such as a myocardial infarction.
One of the ways to treat such disturbances is to identify the conductive pathways and to sever part of this pathway by destroying these cells which make up a portion of the pathway. Traditionally, this has been done by either cutting the pathway surgically; freezing the tissue, thus destroying the cellular membranes; or by heating the cells, thus denaturing the cellular proteins. The resulting destruction of the cells eliminates their electrical conductivity, thus destroying, or ablating, a certain portion of the pathway. By eliminating a portion of the pathway, the pathway may no longer maintain the ability to conduct, and the arrhythmia ceases.
The success and advancement of current therapies is dependent upon the development and use of more precise localization techniques which allow accurate anatomical determination of abnormal conductive pathways and other arrythmogenic sites. Historically, the electrophysiologist has had to compromise between placing the catheter in the place of greatest clinical interest and areas that are anatomically accessible.
One area of advancement in improving localization techniques and accessing additional sites includes the use of curved and steerable catheters. Curved catheters offer improved maneuverability to specific, otherwise inaccessible sites by being shaped specifically to access a particular site. Although perhaps useful for some more accessible sites, the use of this type of catheter has limitations in reaching sites requiring active articulation during placement. Steerable catheters, which may also be pre-curved, proved additional advantages.
While steerability of catheters has improved, there is a need to eliminate significant variations in planarity during deflection of the distal tips of catheters. In accordance with this invention, a catheter is provided that addresses and potentially eliminates significant variation in planarity during catheter tip deflection. The invention also offers a catheter capable of a multitude of angular shaft deflection trajectories through a two or three dimensional range including a catheter that could initially be straight and, upon complete deflection, turn into a loop-shaped catheter. This invention would improve product reliability, consistency, and performance, as well as improve safety of electrophysiology ablation or diagnostic procedures. | {
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A gear-turbofan engine consists of an epicyclic gear system coupling the turbine to the fan. In this manner, both the fan and the turbine can operate at each component's own optimum speed. The fan and the turbine may be coupled to one another through a gear train that is supported by a journal bearing system.
During powered operation of the engine, lubricant is delivered to the journal bearings by means of one or multiple oil pumps. This lubricant develops a hydrodynamic film at the journal bearing surface between the gear bore and the journal pin shaft in order to minimize wear as these surfaces move with respect to one another. The oil pump(s) pump lubricant from an oil sump and deliver pressurized oil to the journal bearings. At the journal bearings, oil is squeezed by the rotation of the gears and generates a hydrodynamic film which is necessary to prevent undesirable metal-to-metal contact between the gear bore and the journal pin shaft.
During the non-operating condition of the engine, the oil pump(s) stop running. If no lubricant is delivered to the journal bearings, the gear bore is in direct contact with the journal pin shaft under the effect of gravity. Under this circumstance, any relative motion between the gear bore inner surface and the journal pin outer surface can cause premature wear and undesirable damage to these surfaces. An auxiliary oil pump is therefore sometimes provided that is mechanically coupled to the epi-cyclic gear system so that the auxiliary oil pump will rotate with rotation of the engine.
In the engine non-operating mode, rotation of the rotor, and hence the gears, can be caused by wind-milling, a phenomenon resulting from ambient wind blowing through the engine, causing the turbofan engine to rotate due to forces imparted by the wind to engine surfaces. Depending on the wind direction, either toward the fan blade through the nacelle inlet or toward the turbine blade through the exhaust duct, the rotor can rotate in either direction, clockwise or counter-clockwise with respect to the pilot view. Rotation of the rotor during the engine non-operating mode may be caused by other means, such as manual rotation to name just one non-limiting example. Any rotation of the rotor during the engine non-operating mode, no matter what is the cause of the rotation, is referred to herein for convenience as “wind-milling”.
Currently, there are no known means to deliver oil effectively to the journal bearings when the wind-milling phenomenon occurs in both rotational directions. The present disclosure is related to a system and method of supplying lubricant to the journal bearings of a gear-turbofan engine operating with a gear train when the rotor is subjected to a wind-milling condition in both directions, either clockwise or counter-clockwise. The presently disclosed embodiments will also find applicability in other applications where lubrication is to be applied when a gear train is operating in either clockwise or counter-clockwise directions. | {
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Obesity is a life-threatening disorder in which there is an increased risk of morbidity and mortality arising from concomitant diseases such as type II diabetes, hypertension, stroke, cancer and gallbladder disease.
Obesity is now a major healthcare issue in the Western World and increasingly in some third world countries. The increase in numbers of obese people is due largely to the increasing preference for high fat content foods but also, and this can be a more important factor, the decrease in activity in most people's lives. In the last 10 years there has been a 30% increase in the incidence of obesity in the USA and that about 30% of the population of the USA is now considered obese.
Whether someone is classified as overweight or obese is generally determined on the basis of their body mass index (BMI) which is calculated by dividing body weight (kg) by height squared (m2). Thus, the units of BMI are kg/m2 and it is possible to calculate the BMI range associated with minimum mortality in each decade of life. Overweight is defined as a BMI in the range 25-30 kg/m2, and obesity as a BMI greater than 30 kg/m2 (see TABLE below).
CLASSIFICATION OF WEIGHT BYBODY MASS INDEX (BMI)BMICLASSIFICATION<18.5Underweight18.5-24.9Normal25.0-29.9Overweight30.0-34.9Obesity (Class I)35.0-39.9Obesity (Class II)>40Extreme Obesity (Class III)
As the BMI increases there is an increased risk of death from a variety of causes that is independent of other risk factors. The most common diseases with obesity are cardiovascular disease (particularly hypertension), diabetes (obesity aggravates the development of diabetes), gall bladder disease (particularly cancer) and diseases of reproduction. Research has shown that even a modest reduction in body weight can correspond to a significant reduction in the risk of developing coronary heart disease.
There are problems however with the BMI definition in that it does not take into account the proportion of body mass that is muscle in relation to fat (adipose tissue). To account for this, obesity can also be defined on the basis of body fat content: greater than 25% in males and 30% in females.
Obesity considerably increases the risk of developing cardiovascular diseases as well. Coronary insufficiency, atheromatous disease, and cardiac insufficiency are at the forefront of the cardiovascular complication induced by obesity. It is estimated that if the entire population had an ideal weight, the risk of coronary insufficiency would decrease by 25% and the risk of cardiac insufficiency and of cerebral vascular accidents by 35%. The incidence of coronary diseases is doubled in subjects less than 50 years of age who are 30% overweight. The diabetes patient faces a 30% reduced lifespan. After age 45, people with diabetes are about three times more likely than people without diabetes to have significant heart disease and up to five times more likely to have a stroke. These findings emphasize the inter-relations between risks factors for NIDDM and coronary heart disease and the potential value of an integrated approach to the prevention of these conditions based on the prevention of obesity (Perry, I. J., et al., BMJ 310, 560-564 (1995)).
Diabetes has also been implicated in the development of kidney disease, eye diseases and nervous-system problems. Kidney disease, also called nephropathy, occurs when the kidney's “filter mechanism” is damaged and protein leaks into urine in excessive amounts and eventually the kidney fails. Diabetes is also a leading cause of damage to the retina at the back of the eye and increases risk of cataracts and glaucoma. Finally, diabetes is associated with nerve damage, especially in the legs and feet, which interferes with the ability to sense pain and contributes to serious infections. Taken together, diabetes complications are one of the nation's leading causes of death.
The first line of treatment is to offer diet and life style advice to patients such as reducing the fat content of their diet and increasing their physical activity. However many patients find this difficult and need additional help from drug therapy to maintain results from these efforts.
Most currently marketed products have been unsuccessful as treatments for obesity owing to a lack of efficacy or unacceptable side-effect profiles. The most successful drug so far was the indirectly acting 5-hydroxytryptamine (5-HT) agonist d-fenfluramine (Redux™) but reports of cardiac valve defects in up to one third of patients led to its withdrawal by the FDA in 1998.
In addition, two drugs have recently been launched in the USA and Europe: Orlistat (Xenical™), a drug that prevents absorption of fat by the inhibition of pancreatic lipase, and Sibutramine (Reductil™), a 5-HT/noradrenaline re-uptake inhibitor. However, side effects associated with these products may limit their long-term utility. Treatment with Xenical™ is reported to induce gastrointestinal distress in some patients, while Sibutramine has been associated with raised blood pressure in some patients.
Serotonin (5-HT) neurotransmission plays an important role in numerous physiological processes both in health and in psychiatric disorders. 5-HT has been implicated in the regulation of feeding behavior for some time. 5-HT appears to work by inducing a feeling of fullness or satiety so eating stops earlier and fewer calories are consumed. It has been shown that a stimulatory action of 5-HT on the 5HT2C receptor plays an important role in the control of eating and in the anti-obesity effect of d-fenfluramine. As the 5-HT2C receptor is expressed in high density in the brain (notably in the limbic structures, extrapyramidal pathways, thalamus and hypothalamus i.e. PVN and DMH, and predominantly in the choroid plexus) and is expressed in low density or is absent in peripheral tissues, a selective 5-HT2C receptor agonist can be a more effective and safe anti-obesity agent. Also, 5-HT2C knockout mice are overweight with cognitive impairment and susceptibility to seizure.
It is believed that 5HT2C may play a role in obsessive compulsive disorder, some forms of depression, and epilepsy. Accordingly, agonists can have anti-panic properties, and properties useful for the treatment of sexual dysfunction.
In sum, the 5HT2C receptor is a validated and well-accepted receptor target for the treatment of obesity and psychiatric disorders, and it can be seen that there is a need for selective 5HT2C agonists which safely decrease food intake and body weight. The present invention is directed to these, as well as other, important ends. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to an integrated circuit and more particularly to an integrated circuit metallization layer having nitride and silicide regions.
2. Background of the Relevant Art
To form an integrated circuit from a group of devices manufactured simultaneously upon the same monolithic substrate, the devices must be electrically connected to one another. The entire process of making ohmic contact to the devices and routing conducting material between ohmic contacts is defined herein as "metallization." While materials other than metal are often used, the term metallization is generic in its application and is derived from the origins of interconnect technology, where metals were the first conductors used. As the complexity of integrated circuits has increased, the complexity of the metallization composition has also increased. Accordingly, metallization may incorporate conductive materials other than metals.
It is not uncommon to have several levels of metallization spaced from each other across the upper substrate surface. In addition, each level of metallization may contain multi-layers of conductive material. As such, metallization may include one or more layers, whereby certain layers may be used in the contact region and other layers configured as interconnect routing between the contacts. Metallization thereby uses specific composition in the contact area to enhance adherence to the underlying silicon. The material used in the contact area, however, may not be suitable as a routing material. Therefore, routing may, for example, utilize a material which is more highly conductive and easier to deposit and etch than the contact area material.
The low resistivity of aluminum, excellent adherence to both silicon and silicon dioxide, and the ohmic contact it makes to silicon assures it as an attractive conductor for use in the multi-layer metallization scheme. Aluminum can be easily deposited on silicon using conventional techniques such as evaporation or sputtering. Unfortunately, with the advent of high density integrated circuits having thinner diffusion junctions, some of the other properties of aluminum have prevented its complete applicability as the sole composition of the metallization layer.
Referring to FIG. 1, modern integrated circuit manufacture often utilizes relatively thin diffusion junctions 10 placed within the upper surface of silicon or gallium arsenide substrate 12. Junction 10, contained within an active region between thick oxide areas 14, provides an ohmic contact region upon which metallization layer 16 can be deposited. If metallization 16 comprises only aluminum without other multi-layer components, then certain deleterious effects may arise when the aluminum is brought in contact with the doped silicon junction. The most important outcome of aluminum and silicon bonding is silicon's appreciable solubility into the aluminum. Aluminum's ability to dissolve thin layers of silicon or silicon dioxide helps ensure good physical contact or adherence. However, if enough silicon dissolves in the aluminum, small pits can form in the silicon surface. The pits are filled with aluminum and the phenomena, often referred to as aluminum spiking, occurs. As aluminum fills the pits or voids left by the outdiffusing silicon, the amount of aluminum fill can extend completely through a thin junction 10 as shown by reference numeral 18. Aluminum passing completely through the junction provides a conductive path through the junction thereby rendering the device inoperable.
The formation of pits or voids within the silicon is often achieved during sintering operation. Sintering at 300.degree. C. produces discernable pitting at depths to 0.2 .mu.m. At 350.degree. C., pits of 0.5 .mu.m have been observed and at 450.degree. C., pits of 2.0 .mu.m may occur. In order to prevent such pitting, aluminum may be deposited saturated with silicon so that it is unable to absorb any more silicon when contacted with the substrate. Alternatively, or in addition to using saturated aluminum, a thin barrier layer may be placed between the aluminum and silicon. The barrier reduces or minimizes cross-diffusion and destructive reaction between silicon and aluminum, yet allows charge carriers to pass freely from the junction to the overlying metallization.
There are many types of barriers which may be used. A sacrificial barrier is one having a finite lifetime. A sacrificial barrier can be initially placed between the aluminum and silicon where it is eventually consumed by the formation and diffusion of intermediate compounds at the aluminum/barrier interface and the barrier/silicon interface. Sacrificial barriers are predominantly made of pure metals such as transition or refractory metals (or bi-metallic alloys). Aluminides and silicides form at the aluminum/barrier interface and barrier/silicon interface, respectively, and then diffuse outward throughout the barrier material until the initial barrier composition no longer exists. Thus, sacrificial barriers provide only a temporary fix to the problem and do not meet the stringent long-term requirements of very large scale integration (VLSI) or ultra large scale integration (ULSI) technology.
A second class of barrier, known as a diffusion barrier, provides an infinite lifetime--as opposed to the finite lifetime of a sacrificial barrier. A diffusion barrier includes a diffusion layer made of an inert material placed between the aluminum and silicon. Diffusion barriers, being inert, do not substantially react with adjacent aluminum and silicon layers. Inert material, however, offers poor adhesion to the adjacent aluminum and silicon. In order to increase adhesion, multi-layers of dissimilar material are formed within the metallization embodying the barrier. A silicide is often used to aid barrier adhesion to silicon. Silicides generally have very high electrical conductivity and therefore make very dependable ohmic contacts. Silicides are formed by depositing a thin layer of refractory metals over the silicon surface, heating the surface to a high enough temperature for the silicon and metal to react in the active region, and then etch away the unreacted metal on top of the thick oxide. Subsequently, additional metallization layers are added to the exposed upper surface of the refractory barrier metal. Refractory metals often require temperatures near 600.degree. C. for silicide formation.
Many different types of refractory metals may be used to form the barrier layer within metallization. As shown below in Table I, refractory metals such as titanium and tungsten provide very low ohmic contact resistance in the active silicon region and therefore are preferred barrier materials.
TABLE I ______________________________________ Resultant Sinter Silicide Resistivity Temperature ______________________________________ TiSi.sub.2 13-16 .mu..OMEGA./cm.sup.2 900.degree. C. TaSi.sub.2 35-55 .mu..OMEGA./cm.sup.2 1000.degree. C. CrSi.sub.2 600 .mu..OMEGA./cm.sup.2 700.degree. C. MoSi.sub.2 100 .mu..OMEGA./cm.sup.2 1000.degree. C. WSi.sub.2 70 .mu..OMEGA./cm.sup.2 1000.degree. C. FeSi.sub.2 >1000 .mu..OMEGA./cm.sup.2 700.degree. C. PtSi.sub.2 28-35 .mu..OMEGA./cm.sup.2 800.degree. C. CoSi.sub.2 18-25 .mu..OMEGA./cm.sup.2 900.degree. C. NiSi.sub.2 50-60 .mu..OMEGA./cm.sup.2 900.degree. C. ______________________________________
When a blanket film of refractory metal is placed over patterned oxide silicon surface and subjected to a thermal sinter, silicide forms only where the metal is in direct contact with the silicon substrate. The unreacted metal can be removed during wet or dry etch processing leaving silicide only in the active regions or windows (such as over source and drain areas). Silicides so formed are often referred to as self-aligned silicides or salicides. The formation of silicides can increase the effective contact area to enhance device operation.
The idea of opening a contact region using normal photolithography and then placing a barrier layer of refractory metal over the upper surface of the contact window is well known. Moreover, subsequent placement of a conductive material over the barrier and across selective regions of thick oxide is also well known. The fabrication steps necessary to deposit, sinter and pattern the various layers used in multi-layer metallization can be fairly complex and difficult to incorporate in a normal process flow. Generally speaking, barrier material and overlying aluminum can be deposited using conventional sputtering techniques. The barrier, however, is generally annealed prior to placement of overlying aluminum. Without anneal, implant-induced defects within the barrier and underlying junction (or active region) may remain thereby causing inoperable or improper circuit operation. Annealing helps induce the movement of implanted ions to their proper positions within the crystallographic lattice network. Such annealing can be performed in a separate rapid thermal anneal apparatus at high temperature and at high pressure as described in Hara, T., et al., "Formation of Titanium Nitride Layers by the Nitridation of Titanium in High Pressure Ammonium Ambient," Appl. Phys. Lett. 57 (16), 15 Oct. 1990; and, Kamgar, A., et al., "Self-Aligned TiN Barrier Formation by Rapid Thermal Nitridation of TiSi.sub.2 in Ammonia, "J. Appl. Phys. 66 (6), 15 Sep. 1989 (incorporated herein by reference). Both the Hara and Kamgar articles describe rapid thermal anneal (RTA) in the presence of ammonium to produce nitridation at the upper surface of the barrier during the formation of silicide at the barrier/substrate interface. The barrier is specifically described as titanium having a thickness of 900 .ANG. to 1200 .ANG.. Pure titanium barriers, however, do not exhibit columnar microstructure such as that present in a combination tungsten and titanium barrier. Unfortunately, tungsten and titanium films behave as rather poor diffusion barriers unless nitrogen is incorporated into the titanium and tungsten structure. As described in Dirks, A , et al , . "On the Microstructure-Property Relationship of W--Ti--(N) Diffusion Barriers," Thin Solid Films, 193/194 (1990) pp. 201-210, the columnar microstructure of combination titanium and tungsten readily combines with nitrogen to provide a more suitable diffusion barrier than offered by pure titanium or pure tungsten.
Barriers having titanium, tungsten and nitrogen inhibit cross diffusion better than if the barrier is pure titanium or pure tungsten. However, the methodology by which nitrogen is added to the combination barrier is often complex and cumbersome. Adding nitrogen to the barrier can fall outside the normal integrated circuit fabrication flow. Additional process or fab step can increase the cost of circuit manufacture and reduce yields. It is therefore advantageous that nitrogen be added during normal processing flow of the integrated circuit. Preferably, additional steps or equipment must be minimized in order to make titanium-tungsten barriers cost effective. It would therefore be desirable to incorporate nitrogen using the same processing equipment utilized, for example, in doping the substrate. Modification to pre-existing equipment must be eliminated or minimized. It is also important that the concentration of nitrogen be closely monitored during anneal, and that only controlled amounts of certain contaminants be allowed to enter the anneal chamber. It would therefore be desirable to utilize a low-pressure annealling chamber to ensure additional or undesirable contaminants not be allowed to enter the resulting barrier and thereby adversely affect device operation. | {
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This invention relates to the coating of steel sheet with a corrosion resistant nonferrous alloy. It relates particularly to a electrodeposited coating of a steel sheet with a zinc-manganese alloy.
It is well-known that steel sheet can be protected from corrosion by a nonferrous metallic coating, such as aluminum, tin or zinc. It is also well-known that alloys of nonferrous metals, such as zinc-nickel alloy or layers of different nonferrous metals, such as zinc and chromium can be used to coat steel to improve its corrosion resistance and other properties, such as paintability. Alloy coatings have wide application in the automotive industry to protect automotive components from corrosion.
Zinc-manganese alloy coatings have been electroplated on steel sheet with generally good results. A process for electroplating steel sheet with a single layer of zinc-manganese alloy coating is described in a paper entitled "Electrodeposition of Zinc-Manganese on Steel Strip" by M. Sagiyama, et al., appearing in the November, 1987 issue of Plating and Surface Finishing. Society of Automotive Engineers Paper No. 860268 (1986) entitled "Zinc-Manganese Alloy Electroplated Steel for Automotive Body" by M. Sagiyama, et al., further describes the properties of a single layer zinc-manganese alloy coating on sheet steel for automotive applications.
These papers describe that single layer zinc-manganese coatings (30-50%) manganese have good corrosion resistance, both before and after painting.
One problem with many nonferrous alloy coatings is the tendency of such coatings to "powder" when the coated steel sheet is being formed or fabricated. Powdering is characteristic of a number of coatings in which portions of the coating crack and flake off the surface of the coated steel sheet during the stamping or forming of the coated sheet. Not only does this result in a partial loss of the protective coating and possibly tiny cracks in the coating, but also the "powder" tends to buildup in the dies used during the stamping or forming of the coated sheet. The accumulated powder in the dies can then cause imperfections in parts subsequently stamped or formed. | {
"pile_set_name": "USPTO Backgrounds"
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Refrigerator appliances generally include a cabinet that defines a food storage chamber. In addition, refrigerator appliances also generally include a door rotatably hinged to the cabinet to permit selective access to food items stored in the food storage chamber. Certain refrigerator appliances, commonly referred to as door-in-door refrigerator appliances, may also include an outer door rotatably hinged to the inner door to permit selective access to the food storage chamber or, alternatively, a food storage chamber positioned between the inner and outer doors. In addition, door-in-door appliances may also include a gasket positioned on the outer door. Thus, when the outer door is in the closed position, the gasket seals against the inner door to enclose the food storage chamber.
For some refrigerator appliances, a door is provided that includes multiple attached pieces. In some instances, it may be desirable for certain pieces to be formed from a different material from the rest of the door and provide a surface that enhances the appearance and usability of the door. In order to join the separate pieces panel to the rest of the door, some existing refrigerator appliances use one or more adhesives. However, this configuration may present a number of issues or drawbacks, especially for pieces forming an inner surface of the door. As an example, the material of an inner surface may expand/contract at a different rate than the piece or material to which it is attached (e.g., by an adhesive). Over time, the difference in expansion/contraction may deteriorate the bond between the adhesive, door, and separate panel. Even if adhesives are not used, the separate panel may bend or buckle as it expand/contracts differently from the rest of the door.
Accordingly, further improvements are necessary to address one or more of the above-identified issues. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a liquid crystal display device including an illumination unit.
Recently, as the characteristics of liquid crystal display devices have been improved, the range of application of liquid crystal display devices has increased. When liquid crystal display devices are used in toys, clocks, clerical machines, terminal units, automobiles, etc., it is necessary to provide an illumination device which is operable for long periods of time, which has a relatively large panel area, and which is decorative and efficient.
A liquid crystal display device having a backlight unit with a small lamp has been employed for wristwatches. The backlight for such a wristwatch display is used to illuminate the face of the watch to make it possible to read the time at night. Conventional types of backlights for liquid crystal display devices are not fully satisfactory in brightness, illumination intensity uniformity and decorative effect. Accordingly, it would be desirable to provide a liquid crystal display device with a backlight which satisfies the above-described requirements, is thin, highly efficient and can be manufactured at a low cost. | {
"pile_set_name": "USPTO Backgrounds"
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Skateboards use a truck for supporting the board on wheels. Some prior art skateboards may be found in U.S. Pat. No. 4,398,734 issued Aug. 16, 1983 to Robert G. Barnard for “Truck Design for a Skate-Type Device”; U.S. Pat. No. 4,251,087 issued Feb. 17, 1981 to H. Gordon Hansen for “Truck Apparatus for Skate and Skateboard Devices”; U.S. Pat. No. 4,155,565 issued May 22, 1979 to David M. de Caussin et al. for “Adjustable Skateboard”; U.S. Pat. No. 4,152,001 issued May 1, 1979 to Tony Christianson for “Skateboard Truck”; U.S. Pat. No. 4,120,510 issued Oct. 17, 1978 to Thomas Gerald Hillard for “Wheeled Skateboards”; U.S. Pat. No. 4,120,508 issued Oct. 17, 1978 to John Steven Brown et al. for “Wheeled Skateboards”; U.S. Pat. No. 4,060,253, issued Nov. 29, 1977 to Eric W. Oldendorf for “Method and Apparatus for Skateboard Suspension System”; and U.S. Pat. No. 3,862,763 issued Jan. 28, 1975 to Gordon K. Ware for “Roller Skate Construction with Releasably, Lockable and Adjustable Action Screw”.
In general, the prior art limits adjusting the distance the wheels and the skateboard while permitting the wheel angle tilt to accommodate the angle of a skateboard during a turn.
The broad purpose of the present invention is to provide an improved skateboard truck construction, in which the skateboard to wheel ground distance is adjustable, allowing the rider to use one skateboard for many currently commercially available axle assembly heights.
Still further objects and advantages of the invention will become readily apparent to those skilled in the art to which the invention pertains upon reference to the following detailed description of the drawings. | {
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Broadband communication networks provide high-speed data communication to many residential neighborhoods and commercial locations. To achieve efficient and reliable data transmission over a broadband communication link, sampling clocks used to sample and receive data must acquire synchronization with the transmitted data stream. In many broadband communication systems, downstream data is broadcast from a central office to all network units served by the central office. A particular network unit will decode only those portions of the downstream data which are addressed to it. As such, the downstream data link is relatively long-lived and the time to initially acquire sampling clock synchronization will have negligible effect on the performance of the downstream data link.
However, many broadband communication systems do not provide a similar long-lived data link for upstream data. Instead, the upstream data link is shared such that each network unit served by the central office is assigned a particular window during which the network unit may transmit its upstream data. The sampling clocks used to sample and receive data sample on the upstream data link must, therefore, resynchronize with each network unit each time the network unit's transmission window begins. Because the transmission windows are usually not long-lived, the time to acquire resynchronization may have a significant impact on the performance of the upstream data link. | {
"pile_set_name": "USPTO Backgrounds"
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Submicron manufacturing uses lithographic techniques to build up layers of materials on a substrate to create transistors, diodes, light-emitting diodes (LEDS), capacitors, resistors, inductors, sensors, wires, optical wires, microelectromechanical systems (MEMS) and other elements which collectively produce a device that serves some function. Substrate lithography is a printing process in which a mask, sometimes called a reticle, is used to transfer patterns to a substrate to create the device. In the production or manufacturing of a device, such as an integrated circuit or a flat panel display, substrate lithography may be used to fabricate the device. When the device to be created is an integrated circuit, typically the substrate is a silicon wafer. In creating an integrated circuit, the lithography is semiconductor lithography which for high volume production is typically a substrate lithography. Other substrates could include flat panel displays, liquid panel display, a mask for flat panel display, nanoimprint masters, or other substrates, even other masks.
In semiconductor lithography, the mask or multiple masks may contain a circuit pattern corresponding to an individual layer, or a part of a layer in multiple patterning processes, of the integrated circuit. This pattern can be imaged onto a certain area on the substrate that has been coated with a layer of radiation-sensitive material known as photoresist or resist. Once the patterned layer is transferred the layer may undergo various other processes such as etching, ion-implantation (doping), metallization, oxidation, and polishing. These processes are employed to finish an individual layer in the substrate. If several layers are required, then the whole process or variations thereof will be repeated for each new layer. Eventually, a combination of multiples of devices, which may be integrated circuits, will be present on the substrate. These devices may then be separated from one another by dicing or sawing and then may be mounted into individual packages.
Optical lithography may be 193 nm light, with or without immersion, or extreme ultraviolet (EUV) or X-ray lithography, or any other frequencies of light or any combination thereof.
Optical lithography that uses 193 nm light waves works with refractive optics and transmissive photomasks or reticles. The masks block, partially block, or transmit the light waves selectively on to a substrate, which is typically resist-coated during the lithographic process, to partially expose or to expose different parts of the substrate or some material on the substrate. The masks are typically at 4× magnification of the target substrate dimensions.
Extreme Ultraviolet Lithography (EUV) uses approximately 13.5 nm wavelength of light with reflective optics. Some implementations use an anamorphic mask with magnifications of 8× in one dimension and 4× in the other dimension.
In general, smaller wavelengths of light are able to resolve finer geometries, finer spaces in between geometries, and a higher frequency (density) of features on the substrate. Also in general, smaller wavelengths of light are more difficult to reliably produce and control. Economically, it is best to use the largest wavelength of light that is able to resolve the feature sizes, spaces, and frequencies that are needed for the device. It is therefore of interest to enhance the resolution achievable on the substrate with any given wavelength(s) of light.
For any lithography of a particular resolution, additional techniques such as off-axis illumination, phase shift masks, and multiple patterning extend the resolution capabilities. When multiple patterning is used, a single substrate layer is exposed multiple times, each time using a different mask which is called a mask layer.
Masks are created by electron beam (eBeam) machines, which shoot electrons at a photo resist coating a surface, which is then processed to produce the desired openings in the mask. The amount of energy delivered to a spot on the mask is called the dose, which may have no energy at a dose set to 0.0 and a nominal dose set to 1.0 by convention. A pattern will be registered when the dose exceeds a certain threshold, which is often near 0.5 by convention. Critical dimension (CD) variation is, among other things, inversely related to the slope of the dosage curve at the resist threshold, which is called edge slope or dose margin.
There are a number of technologies used by eBeam machines. Three common types of charged particle beam lithography are variable shaped beam (VSB), character projection (CP), and multi-beam projection (MBP). The most commonly-used system for leading edge mask production is VSB. VSB and CP are sub-categories of shaped beam charged particle beam lithography, in which an electron beam is shaped by a series of apertures and steered to expose a resist-coated surface. MBP uses plurality of charged particle beams whereas VSB and CP machines typically have a single beam.
It is difficult to print features whose size is similar to or smaller than the wavelength of the light used for lithography. The industry has applied various techniques to address the difficulty of reliably printing a desired shape on the substrate. A computational lithography field has emerged to use computing to enhance the substrate lithography, which in semiconductor lithography is also referred to as wafer lithography. Reticle Enhancement Technologies (RET) include computational methods and systems to design the target reticle shapes with which to project the desired pattern on the substrate more precisely and more reliably across manufacturing variation. RET often use computation to enhance an image on a mask, to print a desired substrate pattern more accurately and more reliably with resilience to manufacturing variation. The two common techniques in RET are Optical Proximity Correction (OPC) and Inverse Lithography Technology (ILT). OPC and ILT are often iterative optimization algorithms that adjust parameters defining the mask until the predicted pattern on wafer is within acceptable tolerances for a set or a range of conditions. OPC manipulates mask geometries and simulates the wafer pattern near target edges. ILT manipulates the mask transmission as pixels, and ILT typically simulates the entire wafer pattern, a process known as dense simulation. An iterative optimization algorithm typically consists of: (1) evaluate a proposed solution to assign a cost which is trying to be minimized; (2) if cost is below a cost criteria, stop; (3) calculate a gradient for each element of the proposed solution which would lead to a lower cost; (4) adjust the proposed solution according to the calculated gradients; (5) go back to (1). Costs are typically defined with positive values where zero is the best possible score as assumed here. However, alternative cost definitions may be used.
RET in general means to improve the printability of all desired features at nominal (expected) manufacturing conditions and within expected manufacturing variation around the nominal manufacturing conditions. Since manufacturing processes are not perfect, the design needs to be resilient to certain expected manufacturing variation. A larger process window means more resiliency to manufacturing variation, specifically that pattern discrepancies through defocus and dose variation are within an acceptable tolerance. Providing sufficient process window for as many of the features as possible is a goal of RET. The percentage of chips that function as specified after fabrication is often referred to as the yield. Many factors affect yield. Improving the process window is generally considered among those skilled in the art to correlate to improving yield. | {
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The invention relates to a liquid crystal display, in particular for a motor vehicle, having a liquid crystal cell having electrical heating formed by an electrically conductive heating layer on a substrate and two busbars which, on opposite sides of the substrate, lead over the width of the heating layer and are in each case provided with a contact connection for connection to a heating current source.
Liquid crystal displays of the above type are currently known and conventional. The electrical heating makes it possible to achieve short switching times even at low temperatures, with the result that, by way of example, DSTN cells are also suitable for use in the motor vehicle. The two busbars, usually called zero-ohm rails, have the task of ensuring a uniform current flow over the entire width of the electrically conductive heating layer, thereby producing uniform heating of the heating layer and thus of the liquid crystal cell over its entire area.
An attempt has already been made to realize the contact connection of the heating layer by busbars which are to be applied on opposite sides of the heating layer and to which, in turn, an electrical conductor is to be soldered, but this causes considerable costs and does not ensure permanent contact connections.
The invention is based on the problem of designing a liquid crystal display of the type mentioned in the introduction in such a way that the means for contact connection of its heating layer are designed as simply as possible and ensure reliable contact connection.
This problem is solved according to the invention by virtue of the fact that the busbars are in each case formed by a clamp having two limbs, one limb of which clamp reaches over the substrate onto the heating layer and the other limb of which clamp reaches under the substrate, and in that, for connection to the heating current source, a spring element is arranged between one limb of the clamp and a printed circuit board.
Such a clamp can be pushed with little assembly effort onto the substrate, where it forms the busbars for uniform distribution of the electric current. Therefore, it is possible to dispense with separate busbars in the form of conductor tracks applied to the heating layer. The clamp according to the invention may preferably be composed of the same material as the spring element bearing against it, with the result that the transition of the electrical energy from the spring element into the clamp does not pose any difficulties. The substrate may be a separate support or a substrate of the liquid crystal cell.
Particularly uniform current distribution in the layer forming the heating can be achieved if the clamp leads over the entire width of the heating layer.
The clamp can be pushed particularly easily over the edge of the substrate, but is supported with a sufficiently high prestress force on the heating layer, if the limb of the clamp which bears on the heating layer has a profile curved approximately in an S-shaped manner, as seen from the side.
The liquid crystal cell together with the mounted clamp can easily be pushed into a light box of a liquid crystal display without the risk of getting stuck or getting caught if, in accordance with another development of the invention, the lower limb of the clamp is designed as a flat web oriented parallel to the substrate.
Uniformly high press-on forces of the clamp over its entire width onto the heating layer can be achieved by the upper limb of the clamp being formed by a multiplicity of spring tongues running next to one another.
If the liquid crystal display is exposed to particularly strong vibrations and shaking during later operation, another development of the invention can provide for the clamp to be additionally fixed on the substrate by an adhesive.
Production tolerances can be compensated to a particularly great extent if the spring element is a helical spring, because the latter can deform on all sides in order to bridge alignment errors. In addition, the helical spring constitutes a space-saving and cost-effective contact connection. Moreover, construction tolerances can be compensated in a simple manner with such an embodiment.
In order to reduce the diversity of parts, it is also possible, however, for the spring element to be formed by at least one spring limb which is integrally formed on the clamp and whose free end bears with prestress on the printed circuit board.
In order to obtain the simplest possible connection to the heating current source, it is proposed that the spring element is formed by at least one spring lug which is integrally formed on the clamp and on whose other end a plug pin is integrally formed, which is plugged into a plug socket on a printed circuit board.
In order that the electrical resistance is as small as possible, it is proposed that a plurality of spring lugs arranged next to one another merge with a connecting web, on which the plug pin is integrally formed. At the same time, press-in lugs oriented perpendicularly to the plug pin can be provided on said connecting web. Said press-in lugs can make it possible to build up a sufficiently large pressure on the plug pin in order to insert it into the plug socket.
In this arrangement, it is expedient that each spring lug forms an arc whose vertex is remote from the clamp. This form can easily be achieved through a single bending operation. It suffices to reliably compensate the tolerances to be bridged.
The contact connection of the clamp to the heating layer is on the one hand intended to have the smallest possible contact resistance. On the other hand, however, the plug-on force is not intended to be to large because this could possibly destroy the heating layer. Therefore, it is proposed that that limb of the clamp which bears on the heating layer, as viewed from the side, runs into a double arc with two bearing points, and that the lower limb, as viewed from the side, runs in a single arc with one contact point, the contact point of the lower limb lying between the bearing points of the upper limb.
On account of different thermal expansion of the clamp and of the substrate to which the clamp is connected, a relative movement between clamp and substrate can occur in the event of large temperature fluctuations. In order to prevent this, it is advantageous to divide the clamp into a plurality of segments in the longitudinal direction and/or to separate individual spring tongues of the clamp to the greatest possible extent (i.e. that adjacent spring tongues are separated from one another over at least ⅔ of their length). When the clamp is separated into a plurality of segments, a spring element for connection to the heating current source is provided on each segment. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to an improved shelf mounting system and to improved parts for such a shelf mounting system or the like as well as to a method of making such a shelf mounting system.
2. Prior Art Statement
It is known to provide a shelf mounting system wherein a shelf unit is mounted to one side of a wall means solely by a plurality of rigid hangers interconnected by interconnecting portions thereof to the shelf unit and having installing portions thereof respectively disposed in a plurality of openings of the wall means and bearing against the other side of the wall means or being received in studs or the like of the wall structure.
For example, see the following seven U.S. patents:
(1) U.S. Pat. No. 1,636,364--Hoegger PA1 (2) U.S. Pat. No. 2,542,753--DeSwart PA1 (3) U.S. Pat. No. 2,909,352--VanBuren,Jr. PA1 (4) U.S. Pat. No. 3,333,555--Kapnek PA1 (5) U.S. Pat. No. 3,527,175--Kapnek PA1 (6) U.S. Pat. No. 3,752,088--Kapnek PA1 (7) U.S. Pat. No. 4,103,854--Pliml et al. PA1 (8) U.S. Pat. No. 2,789,783--Jones PA1 (9) U.S. Pat. No. 3,094,892--Topf PA1 (10) U.S. Pat. No. 3,289,992--Brooks
It is also known to provide a generally J-shaped mounting hanger.
For example, see the following U.S. patent:
It is also known to provide peg board mounting hangers.
For example, see the following two U.S. patents: | {
"pile_set_name": "USPTO Backgrounds"
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In a transmitter of all modern wireless communication links, an output sequence of bits from an error correcting code can be mapped onto a sequence of complex modulation symbols. These symbols can be then used to create a waveform suitable for transmission across a wireless channel. Particularly as data rates increase, decoding performance on the receiver side can be a limiting factor to achievable data rates. | {
"pile_set_name": "USPTO Backgrounds"
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Treatment of bulky, refractory cancers using adoptive transfer of tumor infiltrating lymphocytes (TILs) represents a powerful approach to therapy for patients with poor prognoses. Gattinoni, et al., Nat. Rev. Immunol. 2006, 6, 383-393. A large number of TILs are required for successful immunotherapy, and a robust and reliable process is needed for commercialization. This has been a challenge to achieve because of technical, logistical, and regulatory issues with cell expansion. IL-2-based TIL expansion followed by a “rapid expansion process” (REP) has become a preferred method for TIL expansion because of its speed and efficiency. Dudley, et al., Science 2002, 298, 850-54; Dudley, et al., J. Clin. Oncol. 2005, 23, 2346-57; Dudley, et al., J. Clin. Oncol. 2008, 26, 5233-39; Riddell, et al., Science 1992, 257, 238-41; Dudley, et al., J. Immunother. 2003, 26, 332-42. REP can result in a 1,000-fold expansion of TILs over a 14-day period, although it requires a large excess (e.g., 200-fold) of irradiated allogeneic peripheral blood mononuclear cells (PBMCs, also known as mononuclear cells (MNCs)), often from multiple donors, as feeder cells, as well as anti-CD3 antibody (OKT3) and high doses of IL-2. Dudley, et al., J. Immunother. 2003, 26, 332-42. TILs that have undergone an REP procedure have produced successful adoptive cell therapy following host immunosuppression in patients with melanoma. Current infusion acceptance parameters rely on readouts of the composition of TILs (e.g., CD28, CD8, or CD4 positivity) and on fold expansion and viability of the REP product.
Current TIL manufacturing processes are limited by length, cost, sterility concerns, and other factors described herein such that the potential to commercialize such processes is severely limited, and for these and other reasons, at the present time no commercial process has become available. There is an urgent need to provide TIL manufacturing processes and therapies based on such processes that are appropriate for commercial scale manufacturing and regulatory approval for use in human patients at multiple clinical centers. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The invention relates to an improvement in lockable gelatine capsules and a method and apparatus for roller shaping a locking groove in the forming pin for the cap.
2. Description of the Prior Art
Self locking gelatine capsules are widely used in the pharmaceutical industry. A common type is described in U.S. Pat. No. 3,399,803 entitled "Self-Locking Medicament Capsule" and assigned to Parke Davis and Company, Detroit, Michigan. A corresponding Canadian Patent No. 805,125 entitled "Self-Locking Gelatine Capsule" issued on Jan. 28, 1969. Both patents describe a gelatine capsule cap having a circumferential annular beveled ridge which extends inward from the cap sidewall. Optionally, the capsule body may have a complimentary circumferential groove to mate with the inwardly projecting circumferential ridge on the cap body. The inwardly directed circumferential ridge on the gelatine cap friction looks with the gelatine body or mates with the circumferential grooves in the gelatine body of the capsule, if such a mating groove is present on the capsule body. The beveled ridge on the capsule cap has a triangular contour including leading and trailing sidewall faces having a bevel angle up to about 10.degree. and an optional flat surface between the two beveled sidewalls.
Silimar capsule structures are described in U.S. Pat. Nos. 3,508,678 and 3,664,495. Canadian Pat. No. 930,674 issued on Jul. 24, 1973 and entitled "Locking Capsule" is the foreign counterpart to U.S. Pat. No. 3,664,495. U.S. Pat. Nos. 3,508,678 and 3,664,495 disclose alternative embodiments for self-locking capsules having locking grooves and ridges in the body and caps of the capsule respectively. In addition, both patents further describe the use of indents to provide additional locking security. The indents, known as "prelocks", provide a mechanical fit as distinguished from the friction fit between the inwardly facing locking ridge of the capsule cap and the optional locking groove of the capsule body. Pre-locking indents are now a common feature of modern gelatine capsules.
Additional efforts have been made to improve the locking characteristics of self-locking gelatine capsules. For example, U.S. Pat. No. 3,584,759 entitled "Separation-Resistant Capsule" describes a gelatine capsule in which the cap and body portions each increase in diameter from their domed end towards their open-end so that they mate tightly with each other. The capsule includes a sealing zone where the actual mating of the cap and body takes place. U.S. Pat. No. 4,247,006 describes another technique in which the open end of the body portion of the capsule has a slightly reduced diameter at its open end so as to improve its mating characteristics with respect to the cap portion of the capsule.
The prior art described above lends to have a number of disadvantages. First, the locking ridge and complimentary groove structure of the capsules tends to have angular, i.e. sharp profiles. Note, for example, the "triangular" contour of the locking ridge described in U.S. Pat. No. 3,399,803. The sharp angle of the locking ridge defines a smaller area of locking contact and therefore a weaker frictional mate with the capsule body. Second, the angular nature of the looking ridge also tends to weaken the sidewall of the gelatine cap. Therefore, it is not uncommon to find that a substantial number of capsules are ultimately broken in the cap region due to the relative weakness in the vicinity of the locking ridge. Third, prior art forming pins tend to wear out quickly. In contrast, the capsule pins formed by the method described in this disclosure tend to have a significantly longer life. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a fuel supply system for a boat and an outboard motor. Specifically, the present invention relates to a fuel supply system for a boat having a second fuel tank connected to a first fuel tank mounted on a hull and an outboard motor.
2. Description of the Related Art
Conventionally, a fuel supply system for a boat having a second fuel tank connected to a first fuel tank mounted on a hull is known (See JP A 2001-140720 and JP A Hei 9-88623, for example).
The fuel supply system for a boat described in JP A 2001-140720 and JP A Hei 9-88623 is a fuel supply system for a boat having an outboard motor. In examples disclosed in JP A 2001-140720 and JP A Hei 9-88623, fuel pumped from a fuel tank (first fuel tank) mounted on a hull is contained in a vapor separator tank (second fuel tank). The fuel contained in the vapor separator tank is supplied to a fuel injection device by a fuel supply pump. The vapor separator tank is disposed close to an engine.
However, in the examples disclosed in JP A 2001-140720 and JP A Hei 9-88623, since the vapor separator tank is disposed close to the engine, it is subject to heat radiated from the engine. Therefore, when the engine of a boat is stopped after a heavily-loaded operation, the fuel temperature in the vapor separator tank is increased by heat radiated from the heated engine. Accordingly, the fuel in the vapor separator tank easily becomes vapor (vaporized fuel) and then returns to the fuel tank mounted on the hull. In this case, fuel in the vapor separator tank decreases due to the vaporized fuel that is returned to the fuel tank mounted on the hull. Therefore, during a restart of the engine, it takes a long time to pump up fuel to the vapor separator tank from the fuel tank on the hull, which makes it difficult for the fuel supply pump to efficiently pump up fuel from the vapor separator tank to supply to the fuel injection device. This hampers smooth engine starting. | {
"pile_set_name": "USPTO Backgrounds"
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This application is a 371 of PCT/EP00/04300, published May 12, 2000.
The present invention relates to novel processes for preparing methoxyimino-acetamides.
A process for preparing N-methyl-[2-(2-hydroxy)phenyl]-2-methoxyimino-acetamide has already been described (cf. EP 0 398 692 A2). However, the compounds prepared by this process are only obtainable in moderate yields.
It has now been found that according to process part 1) compounds of the formula (I)
in which
R1, R2, R3 and R4 are identical or different and independently of one another each represents hydrogen, halogen, cyano, nitro, in each case optionally halogen-substituted alkyl, alkoxy, alkylthio, alkylsulphinyl or alkylsulphonyl,
R5 represents substituted or unsubstituted alkyl,
R6 represents hydrogen, substituted or unsubstituted alkyl,
are obtained when
A) according to process step 2), compounds of the formula (IV),
xe2x80x83in which
R1, R2, R3 and R4 are as defined above,
are reacted, in the presence of an acid or an acidic ion exchanger, with an alcohol of the formula (V),
R7xe2x80x94OHxe2x80x83xe2x80x83(V)
xe2x80x83in which
R7 represents substituted or unsubstituted alkyl,
and with a carbonyl compound, which binds the hydroxylammonium chloride eliminated in the reaction forming an oxime, to give compounds of the formula (VI),
xe2x80x83in which
R1, R2, R3, R4 and R7 are as defined above,
and the resulting compounds of the formula (VI) are either
a) according to process step 3), reacted with a hydroxylammonium salt, if appropriate in the presence of a diluent and if appropriate in the presence of an acid or an acid acceptor, to give compounds of the formula (VII),
xe2x80x83in which
R1, R2, R3, R4 and R7 are as defined above,
and the resulting compounds of the formula (VII) are, according to process step 4), reacted with an alkylating agent of the formula (VIII),
R5xe2x80x94Xxe2x80x83xe2x80x83(VIII)
xe2x80x83in which
R5 is as defined above and
X represents halogen, xe2x80x94Oxe2x80x94COxe2x80x94OR5xe2x80x94 or xe2x80x94Oxe2x80x94SO2xe2x80x94Oxe2x80x94R5, where R5 is as defined above,
if appropriate in the presence of a diluent and if appropriate in the presence of a base,
or
b) are, according to process step 5), reacted with an alkoxyamine of the formula (IX),
R5xe2x80x94Oxe2x80x94NH2xe2x80x83xe2x80x83(IX)
xe2x80x83in which
R5 is as defined above,
xe2x80x94 or an acid addition complex thereofxe2x80x94, if appropriate in the presence of a diluent and if appropriate in the presence of an acid or an acid acceptor,
or when
B) according to process step 6), compounds of the formula (IV),
xe2x80x83in which
R1, R2, R3 and R4 are as defined above,
are reacted with an alkoxyamine of the formula (IX),
R5xe2x80x94Oxe2x80x94NH2xe2x80x83xe2x80x83(IX)
xe2x80x83in which
R5 is as defined above,
xe2x80x94 or an acid addition complex thereofxe2x80x94if appropriate in the presence of a diluent and if appropriate in the presence of an acid,
or when
C) according to process step 7), compounds of formula (IV),
xe2x80x83in which
R1, R2, R3 and R4 are as defined above,
are reacted, in the presence of an acid or an acidic ion exchanger, with an alcohol of the formula (V),
R7xe2x80x94OHxe2x80x83xe2x80x83(V)
in which R7 is as defined above,
if appropriate with addition of a hydroxylammonium salt, and the resulting compounds of the formula (VII),
xe2x80x83in which
R1, R2, R3, R4 and R7 are as defined above,
are reacted according to process step 4),
or when
D) according to process step 8), compounds of the formula (X),
xe2x80x83in which
R1, R2, R3, R4 and R5 are as defined above,
are reacted, in the presence of an acid or an acidic ion exchanger, with an alcohol of the formula (V),
R7xe2x80x94OHxe2x80x83xe2x80x83(V)
xe2x80x83in which R7 is as defined above, if appropriate in the presence of a carbonyl compound which binds the hydroxylammonium chloride eliminated in the reaction forming an oxime,
and the compounds of the formula (II) obtained according to proceses A)-D),
xe2x80x83in which
R1, R2, R3, R4 and R5 are as defined above and
R7 represents unsubstituted or substituted alkyl,
are, if appropriate without intermediate isolation of the compounds of the formula (II) (one-pot process),
reacted according to process step 1) with an alkylamine of the formula (III),
R6xe2x80x94NH2xe2x80x83xe2x80x83(III)
in which R6 is as defined above, if appropriate in the presence of a diluent.
Moreover, it has been found that, according to process part 2), compounds of the formula (XI),
in which
Z represents unsubstituted or substituted cycloalkyl, aryl or heterocyclyl,
Q represents oxygen or sulphur,
Y represents halogen and
R1, R2, R3, R4, R5 and R7 are as defined above,
are obtained when compounds of the formula (I) are reacted according to the novel process part 1), and these compounds (I) are either
E) according to process step 9) reacted with pyrimidine derivatives of the formula (XII),
xe2x80x83in which
T1 and T2 are identical or different and represent halogen or xe2x80x94SO2xe2x80x94R8, where R8 is alkyl, aryl or benzyl, and
Y is as defined above,
if appropriate in the presence of a diluent and if appropriate in the presence of a base, and the resulting compounds of the formula (XIII),
xe2x80x83in which
T2, Y, R1, R2, R3, R4, R5 and R7 are as defined above,
are reacted, according to process step 10), with a cyclic compound of the general formula (XIV),
Zxe2x80x94Qxe2x80x94Hxe2x80x83xe2x80x83(XIV)
xe2x80x83in which
Z and Q are as defined above,
if appropriate in the presence of a diluent and if appropriate in the presence of an acid acceptor and if appropriate in the presence of a catalyst,
or
F) are reacted according to process step 11) with compounds of the formula (XV),
in which
Z, Q, T1 and Y are as defined above,
if appropriate in the presence of a diluent and if appropriate in the presence of a base.
Furthermore, it has been found that the Z-isomeric compounds of the formula (XI) are isomerized to E-isomeric compounds of the formula (XI) when Z isomers or E/Z isomer mixtures of the compounds of the formula (XI) are treated with acids, if appropriate in a diluent. The isomerization affords the E isomers in good yields.
Furthermore, it has been found that the Z-isomeric compounds of the formula (XIII) are isomerized to E-isomeric compounds of the formula (XIII) when Z isomers or E/Z isomer mixtures of the compounds of the formula (XIII) are treated with acids, if appropriate in a diluent. The isomerization affords the E isomers in good yields.
In the definitions, the saturated or unsaturated hydrocarbon chains, such as alkyl, alkanediyl, alkenyl or alkinyl, are, including in combination with heteroatoms, such as, for example, in alkoxy, alkylthio or alkylamino, in each case straight-chain or branched having in particular 4 carbon atoms.
Aryl denotes aromatic, mono- or polycyclic hydrocarbons rings, such as, for example, phenyl, naphthyl, anthranyl, phenanthryl, preferably phenyl or naphthyl, in particular phenyl.
Halogen generally denotes fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, in particular fluorine or chlorine. Heterocyclyl denotes saturated or unsaturated, and also aromatic, cyclic compounds in which at least one ring member is a heteroatom, i.e. an atom different from carbon. If the ring contains a plurality of heteroatoms, these can be identical or different. Preferred heteroatoms are oxygen, nitrogen or sulphur. If appropriate, the cyclic compounds form a polycyclic ring system together with further carbocyclic or heterocyclic fused-on or bridged rings. Preference is given to mono- or bicyclic ring systems, in particular to mono- or bicyclic aromatic ring systems.
Cycloalkyl denotes saturated carbocyclic compounds which may, if appropriate, form a polycyclic ring system with further carbocyclic, fused-on or bridged rings.
Halogenoalkyl denotes partially or fully halogenated alkyl. In the case of polyhalogenated halogenoalkyl, the halogen atoms can be identical or different. Preferred halogen atoms are fluorine and chlorine and in particular fluorine. If the halogenoalkyl also carries other substituents, the maximum number of halogen atoms possible is reduced to the remaining free valencies.
The compounds according to the invention can, if appropriate, be present as mixtures of different possible isomeric forms, in particular of stereoisomers, such as, for example E and Z. What is claimed are both the E and the Z isomers, and any mixtures of these isomers.
In general, Z represents in particular:
cycloalkyl having 3 to 7 carbon atoms which is in each case optionally mono- to disubstituted by halogen, alkyl or hydroxyl;
heterocyclyl having 3 to 7 ring members which is optionally substituted by alkyl having 1 to 4 carbon atoms;
or phenyl or naphthyl, each of which is optionally mono- to tetrasubstituted by identical or different substituents, where the possible substituents are preferably selected from the list below:
halogen, cyano, nitro, amino, hydroxyl, formyl, carboxyl, carbamoyl, thiocarbamoyl;
in each case straight-chain or branched alkyl, hydroxyalkyl, oxoalkyl, alkoxy, alkoxyalkyl, alkylthioalkyl, dialkoxyalkyl, alkylthio, alkylsulphinyl or alkylsulphonyl having in each case 1 to 8 carbon atoms;
in each case straight-chain or branched alkenyl or alkenyloxy having in each case 2 to 6 carbon atoms;
in each case straight-chain or branched halogenoalkyl, halogenoalkoxy, halogenoalkylthio, halogenoalkylsulphinyl or halogenoalkylsulphonyl having in each case 1 to 6 carbon atoms and 1 to 13 identical or different halogen atoms;
in each case straight-chain or branched halogenoalkenyl or halogenoalkenyloxy having in each case 2 to 6 carbon atoms and 1 to 11 identical or different halogen atoms;
in each case straight-chain or branched alkylamino, dialkylamino, alkylcarbonyl, alkylcarbonyloxy, alkoxycarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl, arylalkylaminocarbonyl, dialkylaminocarbonyloxy, alkenylcarbonyl or alkinylcarbonyl having 1 to 6 carbon atoms in the respective hydrocarbon chains;
cycloalkyl or cycloalkyloxy having in each case 3 to 6 carbon atoms;
in each case doubly attached alkylene having 3 or 4 carbon atoms, oxyalkylene having 2 or 3 carbon atoms or dioxyalkylene having 1 or 2 carbon atoms, each of which is optionally mono- to tetrasubstituted by identical or different substituents from the group consisting of fluorine, chlorine, oxo, methyl, trifluoromethyl and ethyl;
or a grouping
xe2x80x83in which
A1 represents hydrogen, hydroxyl or alkyl having 1 to 4 carbon atoms or cycloalkyl having 1 to 6 carbon atoms and
A2 represents hydroxyl, amino, methylamino, phenyl, benzyl or represents in each case optionally cyano-, hydroxyl-, alkoxy-, alkylthio-, alkylamino-, dialkylamino- or phenyl-substituted alkyl or alkoxy having 1 to 4 carbon atoms, or represents alkenyloxy or alkinyloxy having in each case 2 to 4 carbon atoms,
and phenyl, phenoxy, phenylthio, benzoyl, benzoylethenyl, cinnamoyl, heterocyclyl or phenylalkyl, phenylalkyloxy, phenylalkylthio, or heterocyclylalkyl having in each case 1 to 3 carbon atoms in the respective alkyl moieties, each of which is optionally mono- to trisubstituted in the ring moiety by halogen and/or straight-chain or branched alkyl or alkoxy having 1 to 4 carbon atoms.
Generally, R5 represents in particular methyl or ethyl.
Generally, R6 represents in particular hydrogen or methyl.
Generally, R7 represents in particular methyl.
Generally, Q represents in particular oxygen or sulphur.
Generally, Y represents in particular fluorine, chlorine, bromine or iodine.
Generally, T1 represents in particular fluorine or chlorine.
Generally, T2 represents in particular fluorine or chlorine.
In general, R1, R2, R3 and R4 are identical or different and independently of one another each represents in particular hydrogen, halogen, cyano, nitro, or alkyl, alkoxy, alkylthio, alkylsulphinyl or alkylsulphonyl having in each case 1 to 6 carbon atoms and being in each case optionally substituted by 1 to 5 halogen atoms.
Preference is given to inventions in which Z represents cyclopentyl or cyclohexyl, each of which is optionally mono- to disubstituted by fluorine, chlorine, methyl, ethyl or hydroxyl;
represents optionally methyl- or ethyl-substituted thienyl, pyridyl or furyl;
or represents phenyl or naphthyl, each of which is optionally mono- to tetrasubstituted by identical or different substituents, where the possible substituents are preferably selected from the list below:
fluorine, chlorine, bromine, iodine, cyano, nitro, amino, hydroxyl, formyl, carboxyl, carbamoyl, thiocarbamoyl, methyl, ethyl, n- or i-propyl, n-, i-, s- or t-butyl, 1-, 2-, 3-, neo-pentyl, 1-, 2-, 3-, 4-(2-methylbutyl), 1-, 2-, 3-hexyl, 1-, 2-, 3-, 4-, 5-(2-methylpentyl), 1-, 2-, 3-(3-methylpentyl), 2-ethylbutyl, 1-, 3-, 4-(2,2-dimethylbutyl), 1-, 2-(2,3-dimethylbutyl), hydroxymethyl, hydroxyethyl, 3-oxobutyl, methoxymethyl, dimethoxymethyl, methoxy, ethoxy, n- or i-propoxy, methylthio, ethylthio, n- or i-propylthio, methylsulphinyl, ethylsulphinyl, methylsulphonyl or ethylsulphonyl, vinyl, allyl, 2-methylallyl, propene-1-yl, crotonyl, propargyl, vinyloxy, allyloxy, 2-methylallyloxy, propene-1-yloxy, crotonyloxy, propargyloxy;
trifluoromethyl, trifluoroethyl, difluoromethoxy, trifluoromethoxy, difluorochloromethoxy, trifluoroethoxy, difluoromethylthio, trifluoromethylthio, difluorochloromethylthio, trifluoromethylsulphinyl or trifluoromethylsulphonyl, methylamino, ethylamino, n- or i-propylamino, dimethylamino, diethylamino, acetyl, propionyl, methoxycarbonyl, ethoxycarbonyl, methylaminocarbonyl, ethylaminocarbonyl, dimethylaminocarbonyl, diethylaminocarbonyl, dimethylaminocarbonyloxy, diethylaminocarbonyloxy, benzylaminocarbonyl, acryloyl, propioloyl, cyclopentyl, cyclohexyl,
in each case doubly attached propanediyl, ethyleneoxy, methylenedioxy, ethylenedioxy, each of which is optionally mono- to tetrasubstituted by identical or different substituents from the group consisting of fluorine, chlorine, oxo, methyl and trifluoromethyl,
or a grouping
xe2x80x83where
A1 represents hydrogen, methyl or hydroxyl and
A2 represents hydroxyl, methoxy, ethoxy, amino, methylamino, phenyl, benzyl or hydroxyethyl, and
phenyl, phenoxy, phenylthio, benzoyl, benzoylethenyl, cinnamoyl, benzyl, phenylethyl, phenylpropyl, benzyloxy, benzylthio, 5,6-dihydro-1,4,2-dioxazin-3-ylmethyl, triazolylmethyl, benzoxazol-2-ylmethyl, 1,3-dioxan-2-yl, benzimidazol-2-yl, dioxol-2-yl, oxadiazolyl, each of which is optionally mono- to trisubstituted in the ring moiety by halogen and/or straight-chain or branched alkyl or alkoxy having 1 to 4 carbon atoms.
Preference is given to compounds in which R5 represents methyl.
Preference is given to compounds in which R6 represents hydrogen or in particular methyl.
Preference is given to compounds in which R7 represents methyl.
Preference is given to compounds in which Q represents sulphur or in particular oxygen.
Preference is given to compounds in which Y represents fluorine or chlorine.
Preference is given to compounds in which R1, R2, R3 and R4 are identical or different and independently of one another each represents hydrogen, fluorine, chlorine, bromine, cyano, nitro, methyl, ethyl, n- or i-propyl, n-, i-, s- or t-butyl, methoxy, ethoxy, n- or i-propoxy, methylthio, ethylthio, methylsulphinyl, ethylsulphinyl, methylsulphonyl or ethylsulphonyl, trifluoromethyl, trifluoroethyl, difluoromethoxy, trifluoromethoxy, difluorochloromethoxy, trifluoroethoxy, difluoromethylthio, difluorochloromethylthio, trifluoromethylthio, trifluoromethylsulphinyl or trifluoromethylsulphonyl.
In a very particularly preferred group of compounds, Z represents optionally substituted phenyl.
In a further very particularly preferred group of compounds
R1 and R3 independently of one another represent methyl and in particular hydrogen and
R2 and R4 represent hydrogen.
Particular preference is given to compounds in which Y represents fluorine.
Particular preference is given to compounds in which Q represents oxygen.
The abovementioned general or preferred radical definitions apply both to the end products of the formula (I) and/or the formula (XI) and also correspondingly to the starting materials or intermediates required in each case for the preparation.
The radical definitions given in the respective combinations or preferred combinations of radicals for these individual radicals are, independently of the combination of radicals given in each case, also replaced by any radical definitions of other preferred ranges.
These radical definitions can be combined with each other at will, i.e. including combinations between the given ranges of preferred compounds.
The compound of the formula (XI-1, E-isomer) is novel and inventive and forms also part of the subject-matter of the invention. It can be used by way of example as pesticide.
The compound of the formula (XI-1, Z-isomer) is novel and inventive and forms also part of the subject-matter of the invention. It can be used by way of example as pesticide.
The isomerization of the compounds of the formula (XI) is preferably carried out after process steps 10 and 11.
Suitable diluents for carrying out the process according to the invention are, by way of example and by way of preference, alcohols, in particular methanol; ethers, in particular tetrahydrofuran; or alkylnitriles, in particular acetonitrile.
Preferred diluents for carrying out the process step 1 are ethers, in particular tetrahydrofuran; or alcohols, in particular ethanol, preferably methanol.
Preferred diluents for carrying out the process step 2 are alcohols, in particular methanol, pyridine, water or mixtures thereof.
Preferred diluents for carrying out process step 3 are alcohols, in particular methanol; dialkyl ketones, in particular acetone; dialkylformamides, in particular dimethylformamide, pyrrolidone, or dialkylacetamides; in particular dimethylacetamide.
Preferred diluents for carrying out the process step 4 are alkylnitriles, in particular acetonitrile.
Preferred diluents for carrying out the process step 5 are alcohols, in particular methanol, pyridine, water or mixtures thereof.
Preferred diluents for carrying out the process step 6 are alcohols, in particular methanol.
Preferred diluents for carrying out the process step 7 are alcohols, in particular methanol.
Preferred diluents for carrying out the process step 8 are alcohols, in particular methanol.
Preferred diluents for carrying out the process step 9 are alkylnitriles, in particular acetonitrile, dialkyl ketones, in particular acetone, dialkylformamides, in particular dimethylformamide, pyrrolidone, or dialkylacetamides, in particular dimethylacetamide.
Preferred diluents for carrying out the process step 10 are alkylnitriles, in particular acetonitrile, dialkyl ketones, in particular acetone, dialkylformamides, in particular dimethylformamide, pyrrolidone, or dialkylacetamides, in particular dimethylacetamide.
Preferred diluents for carrying out the process step 11 are alkylnitriles, in particular acetonitrile, dialkyl ketones, in particular acetone, dialkylformamides, in particular dimethylformamide, pyrrolidone, or dialkylacetamides, in particular dimethylacetamide.
Suitable diluents for carrying out the isomerization are all inert organic solvents. These preferably include aromatic hydrocarbons, such as for example toluene or xylene, esters, such as, for example, ethyl acetate or n-butylacetate, ethers, such as, for example tert-butyl methyl ether, dioxane, tetrahydrofuran or dimethoxyethane, ketones, such as, for example, acetone, butanone, cyclohexanone or methyl isobutylketone, or alcohols, such as, for example methanol, ethanol, n- or i-propanol, n-, i-, or t- butanol, or mixtures thereof with water.
For the purpose of the invention, acids are relatively highly concentrated acids, in particular mineral acids or hydrogen chloride gas.
The preferred mineral acid is hydrochloric acid, in particular hydrogen chloride gas.
For the isomerization, relatively highly concentrated acids, in particular mineral acids or sulfonic acids, for example and in particular sulfuric acid, methanesulfonic acid, hydrochloric acid and hydrogen chloride gas are employed.
The acidic ion exchangers used in the processes according to the invention are preferably perfluorinated ion exchangers.
The processes according to the invention are, if appropriate, carried out in the presence of a suitable acid acceptor/base. Suitable acid acceptors/bases are all customary inorganic or organic bases. These preferably include alkaline earth metal or alkali metal carbonates, such as, for example, potassium carbonate; alkaline earth metal or alkali metal bicarbonates, such as, for example , potassium bicarbonate; primary amines, such as methylanine, tertiary amines, such as trimethylamine, triethylamine, tributylamine, N,N-dimethylaniline, pyridine, N-methylpiperidine, N-methylmorpholine, N,N-dimethylaminopyridine, diazabicyclooctane (DABCO), diazabicyclononene (DBN) or diazabicycloundecene (DBU), particularly preferably alkali metal acetates, in particular sodium acetate.
In process step 1, preference is given to using methylamine.
In process step 3, preference is given to using sodium acetate.
In process step 4, preference is given to using potassium bicarbonate.
In process step 5, preference is given to using sodium acetate.
In process step 9, preference is given to using potassium carbonate.
In process step 10, preference is given to using potassium carbonate.
In process step 11, preference is given to using potassium carbonate.
The alkoxyamines used in process step 5 are in particular methoxyamine and/or its hydrochloride salt.
The alkoxyamines used in process step 6 are in particular methoxyamine and/or its hydrochloride salt.
When carrying out the processes according to the invention, the reaction temperatures can be varied within a relatively wide range. In general, the processes are carried out in a temperature range of from 0xc2x0 C. to the reflux temperature of the mixture in question, in particular at reflux temperature.
The reactions according to process step 1 are preferably carried out in a temperature range from 0xc2x0 C. to room temperature, in particular at 5-15xc2x0 C.
The reactions according to process step 2 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question, in particular at reflux temperature.
The reactions according to process step 3 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question, in particular at room temperature.
The reactions according to process step 4 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question, in particular at reflux temperature.
The reactions according to process step 5 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question, in particular at reflux temperature.
The reactions according to process step 6 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question, in particular at reflux temperature.
The reactions according to process step 7 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question.
The reactions according to process step 8 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question.
The reactions according to process step 9 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question.
The reactions according to process step 10 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question.
The reactions according to process step 11 are preferably carried out in a temperature range from room temperature to the reflux temperature of the mixture in question.
The reactions of the processes according to the invention are carried out under atmospheric pressure, under elevated or under reduced pressure, preferably under atmospheric pressure.
Preferred carbonyl compounds are dialkyl ketones, in particular acetone, aldehydes or glyoxylic acid.
Preferred alkylating agents are carbonates, in particular dialkyl carbonates, particularly preferably dimethyl carbonate, dialkyl sulphates, in particular dimethyl sulphate, or particularly preferably alkyl halides, in particular methyl chloride.
Preferred pyrimidine derivatives of the formula (XII) in process step 9) are trifluoropyrimidine or fluorodichloropyrimidines, in particular 5-fluoro-4,6-dichloropyrimidine.
Particular preference is given to carrying out process part 1A)a) without intermediate isolation of the compounds of the formulae (VI), (VII) and (II) (one-pot process).
Particular preference is given to carrying out process part 1A)b) without intermediate isolation of the compounds of the formulae (VI) and (II) (one-pot process).
Particular preference is given to carrying out process part 1B) without intermediate isolation of the compounds of the formula (II) (one-pot process)
Particular preference is given to carrying out process part 1C) without intermediate isolation of the compounds of the formula (VII) and (II) (one-pot process).
Particular preference is given to carrying out process part 1D) without intermediate isolation of the compounds of formula (II) (one-pot process).
Particular preference is given to carrying out process part 1 and part 2 without isolation of the intermediate compounds (one-pot process).
The starting materials of the formula (IV) used for carrying out the process steps 2), 6) and 7) are known and can be prepared by known processes (cf. Beilstein, E (II) 17, 462; Mameli, G. 56, 768; Chem. Ber. 35 (1902), 1640-1646; Proc. Indian Acad. Sci. Sect. A (1976) 83A(6), 238-242).
Some of the compounds of the formula (VII) required as starting materials for carrying out the process step 4) according to the invention are known (cf. Giannella; Pigini, FRPSAX, Farmaco Ed.Sci., 28, 1973, 157,159), and they are obtained by a novel route according to process step 7) from compounds of the formula (IV), or according to process step 3) from compounds of the formula (VI).
On the one hand, the compounds of the formula (VI) required as starting materials for carrying out the known process step 5) are known and can be prepared by processes known per se, on the other hand, they are obtained by a novel route according to process step 2).
The compounds of the formula (IV) required as starting materials for carrying out the process step 3) according to the invention have already been described in the description of the process step 5).
The starting materials of the formula (X) used in process step 8) in which R1, R2, R3 and R4 represent hydrogen and R5 represents methyl are mentioned by name in EP-398692, the starting materials of the formula (X), used in process step 8) in which R1, R2, R3 and R4 represent hydrogen and R5 represents alkyl are described under formula (VIII) on page 8 and page 14 and page 36 in WO9746542. They are also described under formula (IV) on page 7 and 8 and on pages 17, 19 and 20 in EP-846691.
The starting materials of the formula (II) used for carrying out the process step 1) can be prepared by process part 1Aa), process part 1Ab), process part 1B, process part 1C or by process part 1D by carrying out the process steps successively or by a one-pot process.
The starting materials used for carrying out the process steps 9), 10) and 11) are described in WO 98/21189.
The compounds of the formula (XI) used for carrying out the isomerization are obtained according to process part 1 and part 2.
All other starting materials are customary commercial products or can be prepared from these by simple processes.
Process step 2 is novel and also forms part of the subject-matter of the invention.
The process step 3) according to the invention yields the compounds of the formula (VII). The compounds of the formula (VII) are novel and inventive and form part of the subject-matter of the invention, except for the compounds of the formula (VII-a)
The process step 7) according to the invention yields the compounds of the formula (VII). The compounds of the formula (VII) are novel and inventive and form part of the subject-matter of the invention.
With the aid of the entire process (process part 1 and process part 2), the preparation of the known pesticides of the formula (XI) (cf. WO 98/21189) is considerably improved and simplified.
The process part 1 according to the invention serves to prepare important intermediates of the formula (I) and gives these intermediates a high and improved yield.
In process part 2 according to the invention, too, an increased yield in comparison to known processes can be observed.
By carrying out the isomerization after process part 2, in particular after process steps 10 and 11, the proportion of the E isomer in the isomer mixture is increased. | {
"pile_set_name": "USPTO Backgrounds"
} |
With the advent of desktop and portable computer systems, the problem of maintaining the confidentiality of secure data is increased. This is a particular problem for laptop computers and hand-held personal digital assistants (PDAs) that are frequently used in public locations. Data security is also a problem for other display systems, such as automated teller machines, and Internet terminals in public locations, such as Internet shops and airports.
In recent years, a great deal of effort has been expended on making flat panel display screens as readable as CRT screens by using active matrix technology. However, enhanced readability of displayed data increases the risk of confidential information being viewable by unauthorized persons when portable displays are used in public locations.
One solution is to provide the display with physical “blinders” mounted on the side of the display to limit the angle at which the display can be seen. Another type of mechanical solution uses microscopic louvers to obscure the screen to any viewer not along the axis of the louvers. However, this does not prevent viewing by a person sitting directly behind the user of the display. In addition, this type of arrangement does not allow the user to leave the equipment unattended.
One manufacturer, InvisiView Technologies, Inc., Boca Raton, Fla., removes the front polarizer from a LCD type of device so the displayed image is no longer visible. If the display is viewed through polarized lenses, it becomes visible. This is a partial solution because anyone wearing consumer-grade polarized sunglasses can defeat the system.
U.S. Pat. No. 5,528,319 “Privacy filter for a display device” issued to Austin on Jun. 18, 1996 describes a privacy filter constructed of spaced-apart opaque grids that can be fitted to a display device. The problems with this arrangement is that it requires physical modification of the device, and like the blinders above, only limits the angle at which the display can be viewed.
U.S. Pat. No. 5,629,984 “System and method for data security” issued to McManis on May 13, 1997 describes a display system that alternates data frames with flash frames where an overwhelming majority of pixels are illuminated so that the flash frames have an average intensity substantially greater than the data frames. The user views the display with a shutter device that is synchronized to the displayed frames. The shutter is open for the data frames, and closed for the flash frames. The interspersed flash frames are intended to make it difficult for a viewer without the optical shutter device to intelligibly read the data frames.
The problem with this system is that most people can perceive images even is the relative intensity of darkest elements is only about 1/100 that of the brightest elements. In other words, the intensity of the flash frames would have to be increased by at least 20 db in order for the device to be effective. In a practical LCD applications, the display elements are usually driven at full power to maximize brightness. Therefore, it is problematic whether the driving voltage can be increased by a factor of a hundred. Even if the flash frames can be displayed, it is well known that over illuminating the display screen greatly shortens its useable life-span. In addition, the flash frames would attract attention to bystanders, and the device is more susceptible to counter attacks. | {
"pile_set_name": "USPTO Backgrounds"
} |
Crude oil, condensate and water produced from wells are typically stored in storage tanks located at or near the well sites. The storage tanks provide temporary storage, as the wells may produce at a slow or uneven rate. Periodically, when a sufficient quantity of liquids have been produced and stored in the storage tank, the liquids are discharged from the tank.
One such method of discharging occurs when a tanker truck visits the well or production site. The truck driver manually connects the storage tank to the truck tanker and discharges the tank contents into the tanker. Another method involves automatically discharging, via a pump, the storage tank into a pipeline such as a sales line, which in turn is connected to a larger pipeline or tanker truck.
For example, one common method is to use, a LACT (Lease Automatic Custody Transfer) unit to automatically discharge and sell the liquids. Most LACT units meter the liquids that are sold so that an accurate measurement is obtained. The TACT unit also operates one or more pumps to move the liquids from the tank to the sales line or tanker truck. The LACT unit operates automatically, with no human intervention needed.
The liquid often contains gas in liquid or vapor form. Gas flashes off of the liquid and rises to the top of the tank. This gas is considered a valuable product and is removed from the tank by separate gas processing equipment for sale.
As liquid is removed from the tank, the pressure of the gas above the liquid decreases due to the increase in gas volume. If the pressure of the gas falls too much, a relief valve on the tank opens to admit atmospheric air into the tank. This is done to prevent the walls and exterior shell of the storage tank from collapsing due to a pressure differential between the outside and inside. The storage tank walls, ceiling and floor are thin and cannot withstand a significant pressure differential.
While admitting air saves the tank from collapse, it has detrimental effects on the downstream gas processing equipment, which includes pipelines, compressors, separation and processing equipment. Air of course contains oxygen and this oxygen causes corrosion and other safety concerns in the downstream equipment.
The same problem arises with water storage tanks. Many wells produce water (typically saltwater), in addition to oil and condensates. Much of the water is separated from the oil at the well site. The water is then stored in a tank that is separate from the oil storage tank. As with the oil, gas flashes off the water and is collected for processing and disposal. A pump removes the water from the storage tank and delivers the water to a pipeline truce, for eventual disposal down a disposal well. The pump can remove the water from the tank too fast, resulting in an inflow of atmospheric air into the tank. This air enters the downstream gas processing equipment.
Thus, it is desired to minimize the admission of air into downstream equipment and in particular into the gas stream or gas circuit of the transfer system. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to a positionally adjustable set of multiple probes particularly suitable for delivering multiple liquid samples, a system incorporating the probes and a process for utilizing the probes.
Prior to the present invention, robots have been used in numerous applications to reduce the labor required for repetitive sample processing. One such application involves processing and spotting samples for analysis by mass spectrometry (MS) from micro titer plates (MTP) on to Matrix-Assisted Laser/Desorption Ionization (MALDI) sample plates. Historically to assure proper sample spotting a robot end-user doing MALDI MS would need to conduct a height calibration for specific sample plates in specific racks on the robot deck to xe2x80x9cteachxe2x80x9d the robot where the surface of the sample plate was located in relation to the outlet end of a hollow robotic probe. Having determined the height calibration, the robot would attempt to dispense a small volume of liquid onto the surface of the plate by positioning the hollow probe containing a liquid sample just above the surface and then allowing a hanging drop of the sample to touch the surface, thus causing it to stick and be deposited on the surface. Robotic workstations can hold many racks, which typically hold many sample plates and can be moved to different locations on the robot deck. Even if the software controlling the robot could make the multiple height calibrations required, the operator would be required to conduct the calibration every time the plate or probe is relocated or replaced.
Sample delivering robotic systems become more complicated when multiple probes (e.g., a one by four row) which move in the Z direction (i.e., up or down) with respect to the robot deck are used in the system, particularly when such probes are rigidly attached to a robotic arm. Even if the multiple probes could be perfectly aligned to each other, only one probe would theoretically be positioned in a plane parallel with the receiving sample plate. Because the row of probe tips will not be in a parallel plane, the distance from tips to plate will vary. If the distance is too great, the droplet of sample will not touch the plate and hence the liquid sample will not spot. Conversely, if there is no distance between the probe and plate, or if this distance is too close, then the chemistry previously deposited on the surface could be damaged or the sample may not deposit or deposit off position. Variations that result from manufacturing the robotic system, the racks and the sample plates have proven to be too great to attain the perfect relative positioning between a sample plate and an array of multiple probes. Matters are even more complicated when probes that are assembled as a three-dimensional array, for example in a four by four arrangement, are moved in the Z direction.
It would be desirable to provide a robotic apparatus, system and process which includes an array of multiple probes for delivering liquid samples which can be positioned at a desired position quickly and automatically. In addition, it would be desirable to provide such an apparatus, system and process wherein the multiple probes can be accurately positioned simultaneously rather than individually.
This invention provides an array of probes capable of simultaneously delivering a plurality of samples to a substrate surface wherein the distance between the outlet end of each probe and the substrate surface is essentially the same for each probe. This distance can be accurately controlled each time the substrate surface is replaced with a new substrate surface. The probes are slidably mounted within a probe housing such that the outlet end of each probe is exposed to allow interaction with the substrate surface, and a wall of the probe is contacted with a friction element which exerts a friction force on the probe to retain the probe in place within the housing. In one embodiment, the probes are hollow tubes and an inlet end of the probe is secured to a flexible conduit which permits movement of the probe and which delivers fluid to the probe or removes fluid from the probe. Movement of the probes from an initial position is effected by the application of a second force that is sufficient to overcome the friction force exerted on the probe wall. When the second force is no longer applied to the probes, the friction force retains the probes at a new position.
For the fluid dispense embodiment discussed above, a cycle for using the probe comprises drawing a vacuum within the probe through the flexible conduits in order to aspirate air into the probes. The air functions as a barrier between a wash liquid and a liquid sample within the probe. The robotic system positions the probe housing over the MTP to allow the probes to aspirate liquid sample from the MTP. Thereafter the probe housing is positioned over a MALDI sample plate and the probe housing is lowered such that the probes are then allowed to contact the surface of the sample plate. The force applied to lower the probes is sufficiently large to overcome the friction force exerted by the friction element so that the probes are moved to come in contact with the substrate surface. Since the position of the substrate surface within the robotic system is almost always nonparallel with the ends of the probes, the outlet ends of the probes will be in different positions and thus the robotic system overdrives the lowering probes to make sure that each probe in the array comes in contact with the substrate surface. The probes are then raised to position the outlet ends of each of the probes at a desired distance from the substrate surface, such as about 0.01 inch from the surface. A positive pressure is then applied to the probe so that the liquid samples are deposited on the substrate surface, such as on a plurality of shallow wells on the MALDI sample plate surface. The probe housing is then raised and a plate integral with the probe housing contacts a fixed surface which moves and resets the probes to their initial position. The probes are then directed to a waste container whereupon the pressure within the probe is increased in order to deliver wash liquid from the flexible conduits through the probes to render them sufficiently clean to process additional samples without contamination. The cycle then is repeated with a replacement sample plate being positioned within the robotic system for sample spotting.
The use of the friction element and the fixed surface to reset the probes permits repeated use of the probes wherein the probes are moved simultaneously to adjust to the surface configuration of a given substrate surface without the need to calibrate the position of each probe individually. | {
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This invention relates in general to apparatus for sensing displacement or position of an object, and in particular to apparatus which utilizes a flexible moveable band or other moveable element to convert a physical measure of displacement and position of an object into an electrical signal representing such measure.
In the operation of various mechanical and electro-mechanical systems, it is necessary to monitor the position and displacement of either some element of the system or some object which is not part of the system. For example, in robotic systems (a technology whose use is dramatically increasing) it is almost always necessary to monitor and control the movement and position of various component parts of the systems, such as an arm, fingers or other grasping elements, etc. Such monitoring and control yields the dexterity and precision required for a robotic system to carry out its functions.
Prior art mechanisms for sensing position and displacement have most often utilized a direct connection between the article or object whose position or displacement was to be monitored, and some type of gauge, needle or other visual indicator. Movement of the article or object would thus cause a corresponding movement of the gauge or needle. As expected, such mechanisms have typically been large and cumbersome and have lacked precision in carrying out the monitoring function. Further, since some type of sliding action of some part of the measuring mechanism typically was involved, friction was present which, of course, resulted in wear.
Although electronic apparatus for measuring position and displacement has come into greater use in recent years and has at least partially solved the bulkiness and imprecision problems of the prior art mechanisms, such apparatus has been complicated in design and, as a result of such complication, generally lacking in reliability. Also, the contact friction and attendant wear generally remained. | {
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Businesses are continually trying to improve the services that they provide to their customers. To better address their customer needs, businesses often provide “customer service departments.” These departments typically employ individuals (sometimes referred to as “agents” or “representatives”) who answer questions, inquiries, complaints and/or other sales and service issues. At a most basic form, an agent communicates with customers via a telephone to orally answer sales/service inquiries of customers who call the customer service department.
Customer relationship management (CRM) systems have become popular in recent years to automate interactions between businesses and customers. Using hardware and software, many tasks traditionally performed by agents may be performed electronically. For instance, customers may listen to prerecorded messages in automated voicemail systems (a form of CRM) and make menu selections using a telephone keypad.
However, businesses, products, and customers may vary greatly from one situation to another. What works very well for one business may not work as well for another. Given this, CRM systems are often customized for each business. This customization may be expensive and lengthy, involving several groups of individuals to provide to businesses with, for example, customized software code, customized hardware, customized applications, and the like.
For example, to allow a business to access client account information via the web, a web application customization may involve a web application developer, a web designer and a database application developer. The web application developer may be responsible for taking business requirements and for developing the complete web application. The web application developer may ask a web designer to create a user interface (UI) mock up.
The web application developer or the designer may be familiar with web development. Either may create files using hypertext markup language (HTML), Active Server Page (ASP) and/or JavaServer Page (JSP) scripting, for example. However, most web application developers and web designers are unfamiliar with the configuration of underlying database(s) and/or database application(s) (e.g. a CRM application) that may provide information and functionality relevant to the application. Therefore, a third group of developers, e.g. database application developers, often help create the custom application.
The database application developer may reconfigure database(s) and/or database application(s) to meet the specific business requirements. For example, a database application developer may configure and/or create templates, applets, repository views, business objects, business components, data services and network services. To accomplish these tasks, the database application developer is usually specially trained in skills specifically relating to a particular database and/or database application. For example, a Siebel® application developer may be trained to work with eScript/Siebel VB™, BrowserScript™, Siebel® object configurations and Siebel® templates.
Once the database(s) and/or the database application(s) are configured and useful interfaces or objects created, the database application developer may then communicate instructions to the web application developer on how to access the interfaces and/or objects. Using these interfaces and objects, the web application developer may create a front end (e.g. a GUI) to provide user access to the database.
This customization process may take weeks, if not months, causing delays in deployment of the application. For example, the web application developer may be unfamiliar with new and/or existing database application interfaces, as well as with the database(s) structure. This unfamiliarity may make it difficult to request the proper modifications. This unfamiliarity may also add development time to allow the web developer to learn how to access and interact with the interfaces in the application code. Even if a web application developer is familiar with the interfaces, the developer may have to write and debug code to create the proper custom application.
Also adding to deployment time is the database application developer's tasks of configuring the database application to support the custom application, e.g. modifying an existing feature, adding a feature, updating a component, installing components, or the like. Thus, what is needed is an improved system and method for generating a custom application. | {
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Orthopaedic surgical procedures often involve the use of a fixation device. Usually an access hole is produced in a bone or soft tissue wherein a suitable fixation device can be fastened. Apart from screws, expandable fixations devices can be used which are inserted into the hole in a collapsed state and transformed into an expanded state once being correctly positioned.
In one example orthopaedic surgical procedure, such as a lumbar microdiscectomy, radiculopathy is treated by surgically removing the herniated nucleus pulposus to achieve neural decompression. The lumbar microdiscectomy is one of the most common spinal surgeries performed today. Many patients find relief with this procedure, but for others, the disc could re-herniate through the opening in the annulus resulting in continuing pain and potentially requiring additional surgery. Currently, the standard microdiscectomy technique does not involve closing the annular defect and presents the surgeon with a dilemma. The surgeon may elect to remove the herniated portion of the nucleus impinging on the nerves, which treats radiculopathy, but may increase the risk of post-operative reherniation of the remaining nucleus through the existing defect of the annulus. Alternately, the surgeon may elect to perform extensive debulking, in which most of the remaining nucleus material is removed in addition to the herniated portion to minimize the risk of post-operative reherniation. However, the risk of post-operative disc height collapse and subsequent progression to lower back pain increases.
Conventional expandable implants include a sleeve with an expandable portion having plurality of fingers or expandable parts formed by intermediate slots or holes in the peripheral wall of the sleeve and a compression element extending through the central bore of the sleeve. The compression element can be coupled to the front end of the sleeve so that upon pulling said compression element towards the rear end of the sleeve said fingers or expandable parts are bent radially outwards so as to transform said expandable portion from its collapsed state to its expanded state. | {
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Traditional approaches for managing enterprise data revolve around a batch driven Extract Transform Load (ETL) process, a one size fits all approach for storage, and an application architecture that is tightly coupled to the underlying data infrastructure. The emergence of Big Data technologies have led to the creation of alternate instantiations of the traditional approach, one where the storage systems have moved from relational databases to NoSQL technologies like Hadoop Distributed File Systems (HDFS). In some cases, traditional approaches to data control in the context of Internet of Things (IoT) and other enterprise data settings have brought forth challenges due to content heterogeneity, requirements of scale, and robustness of ETL processes. | {
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1. Field
The disclosed subject matter relates to a vehicle structure/surface that has a three dimensional tactile coating and its associated method of manufacture. More specifically, the disclosed subject matter relates to a vehicle substrate surface that is provided with a coating that has a three-dimensional tactile pattern as well as a unique three dimensional appearance for either interior or exterior surfaces.
2. Brief Description of the Related Art
The relevant art describes various ways of applying paints and/or metal film layers to substrates in order to achieve a particular visual appearance. These coating methods depend, in part, on the type of substrate, the coatings to be applied, and the desired visual appearance of the substrate. For example, in the automotive industry, it is advantageous to provide certain elements, such as body trim pieces, with a metallic appearance to match an automobile body part, or even to enhance the appearance of said body part.
In the automotive industry, there has been a great demand for a protective, functional, yet decorative coating that would also serve to minimize or mask the appearance of surface defects. However, this demand has not been previously met.
For example, U.S. Pat. No. 5,017,638 describes a novel metallic paint film giving an intensified metallic feeling when viewed at the front, as well as having good flip-flop characteristics. Also, U.S. Pat. No. 3,580,768 describes a paint with a three-dimensional effect created by applying liquid drops onto a painted surface, drying the paint surrounding the liquid drops, then re-spraying the entire surface with the paint. Japanese Patent No. 2000052700 describes an automobile coating film that includes paint particles of coarsened paint to provide mottled patterns of light luminous parts. Further, Japanese Patent No. 10005688 discloses a three-dimensional design pattern for an automobile surface which is accomplished by applying a photo-curable material to the surface, applying a pattern film, photo-curing the exposed photo-curable material, then removing non-cured parts to form a projected pattern. U.S. Patent Publication No. 2002/0119259 describes a physical vapor deposition (PVD) film on an automobile body that provides a decorative metallic appearance and can be coated by ultraviolet (UV) curable paint. Further, U.S. Pat. No. 5,017,638 discloses a metallic paint film that provides a “three-dimensional effect.” Each of the above-described related art references is hereby incorporated by reference in its entirety.
However, the above-described related art does not solve the immediate need for coating a substrate to produce a decorative effect. | {
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In the practice of digital color image processing, an original color image, such as a photographic negative, is sampled periodically in three colors (e.g. red, green and blue) to produce a digital representation of the original color image. The digital color image is processed by applying digital image processing functions to improve such image qualities as sharpness, tone-scale, and color balance. The processed digital color image is then displayed on a display medium such as photographic film or paper.
FIG. 3 is a schematic diagram illustrating apparatus for digital image processing. Such apparatus includes an input device 1 for sampling the original color image in each of three colors, and analog-to-digital converters 2 for producing the digital color image in the three colors. Commonly employed input devices include drum and flat bed scanners, linear and area solid state image sensing arrays, and CRT and laser flying spot scanners, each being provided with appropriate color filters to produce the color separations.
Each digital color separation image is stored in a mass storage memory 3, such as a solid state memory frame-buffer, magnetic tape or disc storage device. A digital computer 4 applies the various image processing functions to the digital color image to produce the processed digital color image.
The digital computer 4 may comprise a main frame general purpose digital computer, or for higher speed operation, a digital computer specially configured for high speed digital processing of color images.
The processed digital color image is converted to sampled analog form by digital-to-analog converters 5 and is displayed on an output device 6 such as a drum or flat bed graphic arts scanner, or a CRT or laser flying spot scanner. The elements of the image reproduction apparatus communicate via a data and control bus 7.
As noted above, among the processing functions performed by the digital computer are the improvement of the tone-scale and color balance of the color image. In the article entitled "Tone Correction of Color Picture by Histogram Modification" by Yoichi Miyake, Nippon Shashin Sakkaishi, V. 48(2), pp. 94-101, 1980, the author proposes a digital color image processing method wherein the tone-scale corrections are effected by modifying the histogram of color values of the green separation image. Color corrections are implemented by solving a conventional set of color masking equations of the form: EQU R'=a.sub.11 R+a.sub.12 G+a.sub.13 B (1) EQU G'=a.sub.21 R+a.sub.22 G+a.sub.23 B (2) EQU B'=a.sub.31 R+a.sub.32 G+a.sub.33 B (3)
where the matrix of color correction coefficients a.sub.ij are determined primarily by the characteristics of the input and output media.
An improvement to this process wherein both tone scale and color balance are corrected using histogram modification techniques is disclosed in copending U.S. patent application Ser. No. 730,627 filed May 6, 1985, by Alkofer.
According to the digital color image processing method of Alkofer, a Laplacian filter is applied to each of the color components of the image to detect local contrast. The color values are divided into contrast intervals, and one of the contrast intervals is selected based on the similarity of the histograms of color values in the selected contrast interval. The histograms of color values in the selected contrast interval are normallized to produce color reproduction functions, and the color reproduction functions are applied to the color components of the digital color image.
The method of Alkofer is based upon two principle observations regarding the statistical properties of the color values in a high quality color image. The first of these principles is that a truly random sample of color values (e.g. photographic density or log radiance) in a high quality color image will form a normal (Gaussian) distribution. The second principle is that the standard deviation of a random sample of color values is invariant with respect to wavelength (i.e. color). A truly random sample of color values of one color will have the same standard deviation as a truly random sample of another color.
The first principle noted above implies that a function that normalizes a random sample of color values will serve well as a color reproduction function, assuming that any deviation from normality in the random sample was caused by some "problem" with the original. The first principle combined with the second principle noted above implies that color values in all three colors having an equal distance in their number of standard deviations from the means of their respective color distributions should always combine to produce a neutral (i.e. gray).
The degree of success (i.e. the appropriateness of the color corrections) achievable by this method is a strong function of the randomness of the sample of color values used to generate the color reproduction functions. Alkofer relied upon the selection of color values from the contrast interval based upon the similarities of the histograms of color values in the contrast interval, to insure the desired randomness in selection of color values from the image. While Alkofer's method represents a subtantial improvement over the prior art, there is still observed to be some situations in which the "randomness" in selecting color values is perturbed by large areas where film grain noise predominates in an image (such as blue sky, causing a subtle yellow shift in the processed image) or areas of fine texture (such as grass or foilage, causing a subtle magenta shift in the processed image).
It is the object of the present invention to provide an improved color digital image processing method, and in particular to provide an improved method for sampling the color values in a color image for use in normalizing the sample of color values to produce color reproduction functions. | {
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1. Field of the Invention
This invention relates to color cathode ray picture tubes, and is addressed specifically to a color cathode ray tube system having an improved unitized, three-beam, in-line electron gun. The system and associated electron gun according to the invention have application to all types of color television picture tubes, including those used in home entertainment television receivers. The system is especially valuable when applied to special-purpose high-resolution color image tubes that require beam spots that are exceptionally small in diameter, uniorm in size, and symmetrical all over the screen. Tubes of this type include medium-resolution and high-resolution monitors. An example of such a special-purpose tube is one that has a flat faceplate and an associated foil tension mask; a tube of this type is described and claimed in referent copending application Ser. No. 832,493 of common ownership herewith.
Desired performance characte-ristics of color cathode ray tube systems include high resolution, picture brightness, and color purity. Resolution is largely a function of the size and symmetry of the beam spots projected by the electron gun of the tube. Beam spots are desirably small, round, and uniform in size at all points of landing on the screen. Achievement of these ideals is difficult because of the many factors which exert an influence on beam spot configuration. As a result of such factors, beam spots that are smal- and symmetrical at the center of the picture imaging field can become distorted at the periphery of the field, for reason which will be described.
Key factors which influence beam spot size, uniformity and symmetry in picture tubes include the following:
(a) electron gun design, especially the design of the means for focusing and converging the beams in three-beam, in-line guns;
(b) potential of the cathode ray tube screen;
(c) magnitude of the beam current;
(d) the "throw" distance from the electron gun to the screen; and,
(e) the magnitude of beam-distorting influences, such as astigmatism engendered by a self-converging yoke, or that inherent in the gun design.
The ability of an electron gun to form small, symmetrical beam spots is a major factor in achieving optimum resolution. The task of designing guns with this capability has become more challenging because of the reduction in diameter of the CRT neck. This physical constraint has been largely overcome by new, more effective gun designs, such as the gun having an extended field main focus lens described and claimed in U.S. Pat. No. 3,995,194 assigned to the assignee of this invention.
Convergence of the three beams of an in-line electron gun is provided in present-day television systems primarily by the self-converging yoke. This type of yoke is a hybrid having toroidal-type vertical deflection coils and saddle-type horizontal deflection coils. The yoke contains windings which produce an astigmatic field component that has the effect of maintaining the beams in convergence as they are swept across the screen. The converging effect is shown highly schematically in FIG. 1, in which an electron gun 10 is depicted graphically as emitting three beams 12, 13 and 14 which diverge from a common plane 16 to impinge on a curved screen 18. The three beams are shown as being converged at the center point 20 of the screen 18. Due to the effect of the self-convrging yoke, the three beams are also caused to be in convergence at the side of the screen 18, as indicated by point 22, even though the distance that beams must travl from the plane of deflection 16 t point 22 is greater than from the plane of deflection 16 to center point 20 of the screen.
The convergence achieved is not without cost, however, as the beam spots are subject to distortion in the peripheral areas of the screen. The distortion is acceptable in conventional tubes that have the curved screen as the benefits and costs savings of the self-converging yoke outweigh its liabilities.
However, when the screen is flat, as indicated by screen 24 in FIG. 2, the self-converging yoke is unable to maintain beam convergence, as indicated by the spread of the beam spots 28 at the sides 26 of screen 24. In addition to the spread, the spots 28 will be noted as being elongated. This elongation is due primarily to the self-converging yoke. The astigmatic field component, while self-converging the beams, undesirably induces deflection defocusing of the beams when the beams are deflected away from the screen center. The effect is indicated diagrammatically in FIG. 3 by beam spots 34. The elongation of the beam spots at the peripheries of the faceplate, and the relative increase in spot size, is indicated in greater detail in FIG. 3A. The beam spots 34 will be seen as comprising a bright core 34A, and transverse to the core, a dim "halo," 34B. The size and contour of the center beam spot 36 is indicated to illustrate the magnitude of the spot size increase and distortion at the corners of the screen. Attempts to focus such beams are largely ineffectual due to the astigmatic effect--focusing merely results in what appears to be a "rotation" of the spot in that the core becomes the halo and the halo becomes the core, without restoration of center-screen dot contour and size.
The distortion of the beam spots at screen peripheries is attributable to the nature of the field of the yoke that provides the desired beam convergence. The field produced by the yoke has the shape of a pin-cushion for the horizontal deflection component, and the shape of a barrel for the vertical deflection component. In addition to the dipole effect which deflects the beams, a quadrupole, astigmatizing effect is also produced which distorts the beams at the screen peripheries, as indicated in FIGS. 3 and 3A.
As has been noted, the effect is tolerable in conventional tubes where the screen is curved, as shown by FIG. 1, and it is acceptably within the capability of the self-converging yoke to converge the beams without undue distortion. However, when the screen is flat, as indicated by FIG. 2, the astigmatic effect of the self-converging yoke is less tolerable, especially in high-resolution cathode ray tubes. Attempts to further modify the configuration of the self-converging yoke field to adapt it to a flat screen may well increase distortion outside the limits of acceptability. The self-converging abiity of the yoke was already stretched to its limit in its application to the curved screen, before the advent of the flat tension mask tube.
2. Prior Art
Prior art structures for statically converging electron beams have relied upon a variety of techniques such as the use of maghetic influences within and/or outside the tube envelope, and the use of electrostatically charged plates. Also, the prior art shows many examples of causing static beam convergence by inducing an asymmety in an electrostatic field formed at the interface of two spaced electrodes. Prior art techniques for inducing electrostatic field asymmetry have included offsetting the apertures in the opposing faces of two electrodes, and slanting one or more of the opposing faces so that the space lying between is in the form of a wedge-techniques described in U.S. Pat. No. 4,058,753 of common ownership herewith, and in U.S. Pat. No. 2,957,106.
Dynamic convergence means is described in U.S. Pat. No. 3,448,316. Three in-line electron beams generated by three cathodes cross over in the electrostatic field of a main lens. The center beam (green) follows a straight-line path, but the two outer "red" and "blue" beams exit the lens in divergent paths. The beams paths are refracted to converge by electron prisms that enclose the beams, and which are located beyond the exit-point of the beams from the gun. The potential on the outer ones of the electron prisms is made adjustable to provide for static convergence of the red and blue beams at the shadow mask. The center beam is unaffected as the potential on the two inner plates through which it passes is left unchanged. Dynamic convergence is attained by changing the convergence control voltage on the outer prisms at the horizontal scanning frequency. The waveform of the convergence voltage is in the form of a parabola.
In U.S. Pat. No. 4,520,292, von Hekken et al discloses means formed in the screen grid of an electron gun for urging the outer two beams of a three-beam electron gun into convergence with the center beam. The screen grid configuration includes a transversely disposed recessed portion having a substantially rectangular central portion and substantially triangular end parts. The total effect is to tilt the field lines within the reessed portion so that the outer beams converge.
In U.S. Pat. No. 4,058,753, of common ownership herewith, there is disclosed a three-beam electron gun for a color cathode ray tube having an extended field main focus lens means. The focus lens means has for each beam at least three electrodes including a focus electrode for receiving a variable potential for electrically adjusting the focus of the beam. In succession down-beam, there are at least two associated electrodes having potentials thereon which form in the gaps between adjacent electrodes significant main focus field components. To adjust beam focus, the strength of a first of these components is controlled by adjustment of the voltage received by the focus electrode. The strength of the second of the field components is relatively less than that of the first component. Each of the lens means is characterized by having addressing faces of the associated electrodes which define the second field component being so structured and disposed as to cause the second field component-to be asymmetrical and effective to significantly divert the beam from its path in convergence of the beams without any significant distortion of the beam, and substantially independently of any beam-focusing adjustments of the first field component. Electrode structures for producing asymmetric field components include a gap angled forwardly and outwardly, a wedge-shaped gap, and radially offset apertures.
An electron gun system providing beam convergence for use in a color CRT display system is disclosed in referent copending application Ser. No. 921,168. Means including cathode means develop three electron beams, two of which are off-axis with respect to a center axis of the gun. A plurality of electrodes means provide shaping and focusing and assist in the converging of the beams at the screen. Means are provided for developing and applying to the electrode means a pattern of potentials which form field components in the gaps therebetween; at least one of the electrode means receives a varying dynamic focusing voltage for dynamically focusing the beams as they are deflected across the screen. At least selected ones of the plurality of electrodes means for the off-axis beams are so structured and arranged as to cause a plurality of the field components to be asymmetric and effective to converge the off-axis beams. The strengths of the asymmetric field components vary in response to changes in the dynamic focus voltage. The asymmetric field components according to the invention have such polarity and strength, due to the structuring and arranging of the electrodes, and the application of the pattern of voltages, that a change in the levels of the dynamic focus voltage causes a change in the strength of each of the asymmetric field in a direction effective to additively deflect a common off-axis beam in a common angular direction so as to create a strong dependency of the convergence of the off-axis beams on variations in the focus voltage.
An electron gun according to the invention disclosed in copending application Ser. No. 832,568 comprises means including cathode means for developing an eletron beam. Main focus lens means provide for receiving the beam and forming a focused electron beam spot at the screen of the tube. The main focus lens means has a plurality of electrodes situated on a common axis. Means are provided for developing and applying to the electrodes potentials effective to form field components in the gaps between adjacent electrodes. The lens means is so structured and arranged as to cause at least one of the field components to be asymmetric and effective to significantly divert the beams from a straight-line path through a predetermined angle. Means for developing and applying a varying voltage to at least one of the electrodes causes the strength of the asymmetric field component, and thus the angle by which the beam is diverted, to vary.
Takenaka et al in U.S. Pat. No. 4,334,169 shows embodiments of an electron gun with a three-element main focus lens (G1, G2 and G3) and outer beam converging means at the field between the center electrode (G2) and the accelerating electrode (G3) of the main focus lens. The convergence means comprise offset apertures and apertures lying at an angle with respect to the gun axis to render the field between asymmetric. The G1 and G2 electrodes are electrically inked and receive the focusing voltage. An aperture electrode is located intermediate to G1 and G2 of the main focus lens and is electrically linked to the accelerating electrode of the prefocusing section. The object is stated to be the maintenance of the pre-established convergence of the outer beams, despite changes in the focusing voltage.
Other representative disclosures having electrode structures that influence beam convergence include:
U.S. Pat. No. 3,952,224 to Evans
U.S. Pat. No. 3,772,554 to Hughes
U.S. Pat. No. 4,473,775 to Hosokoshi et al
U.S. Pat. No. 4,513,222 to Chen
The performance of cathode ray tubes is also a function of the ability of the gun and associated systems to establish and maintain focus at all points on the screen. Conventional curved-screen, curved-mask tubes, because of the curvature of the screen, are able to attain tolerable focusing performance on all points on the screen with little or no dynamic focusing. However, tubes having a flat faceplate exacerbate the focusing problem particularly at the screen edges due to the lack of curvature of the screen. For high-performance flat-faced tubes, dynamic focusing of electron beams is very desirable.
Techniques for dynamically varying the focus of electron beams are well-known in the art. Dynamic focusing is used to cause a beam to be in focus at the sides of the picture imaging field as well as at the center of the field. The need for dynamic focusing arises from the aforedescribed accurate scanning of the beam with relation to the relatively planiform faceplate.
Dynamic focusing of a beam can be accomplished electronically by menns of a focus-control signal modulated at the scanning frequency, with the signal being applied to a suitable beam-focusing electrode. Dynamic focusing means is disclosed by Richard in U.S. Pat. No. 3,412,281. An A. C. control signal is employed which is proportional to the distortion due to defocusing inherent in tube faces, according to Richard. The A.C. control signal is converted into a D.C. control signal which may be added to the relatively high-level constant voltage of the tube focusing circuit. Another approach to dynamic focusing is disclosed by U.S. Pat. No. 2,801,363.
Three patents to Chen disclose astigmatism-forming electrode structures. In U.S. Pat. No. 4,234,814, a gun is described that has a screen grid with an aperture comprising a rectangular slot portion facing the control grid, and a circular portion facing away from the control grid. The slot portion of the apertures is said to create an astigmatic field that produces under-convergence of the beam in the vertical plane only to avoid and/or compensate for vertical flae distortion of the beam spot at off-center positions on the image screen. In U.S. Pat. No. 4,319,163 of Chen, a gun lower end is disclosed that includes a cathode, a control grid, a first screen grid electrode having a horizontally elongated rectangular aperture, and a second screen grid electrode having a circular aperture. ln operation, the second screen grid is energized with a DC bias voltage and the control grid and first screen grid is energized with a DC bias superposed with a substantially parabolically shaped dynamic signal synchronized with either or both the horizontal and vertical deflection signals. It is stated that the astigmatic optics of the beam forming means varies in strength in phase with the beam scan so as to provide optimum correction for flare distortion of the beam. In a third Chen Patent, U.S. Pat. No. 4,523,123, an inline gun includes a plurality of electrodes including a cathode, a control grid, a screen grid and a main focus lens. The screen grid has a given thickness with a plurality of transverse slots formed therein. The sots have a depth less than the thickness of the screen grid. An aperture is formed in each of the slots. The outer slots are asymmetric with respect to the apertures therein and are displaced transversely toward the center aperture. The transverse slots in the screen grid are said to compensate for the vertical flare distortion of the beam spot at off-center positions on the screen, and the asymmetric location of the outer slots is said to reduce the horizontal convergence sensitivity of the outer beams with respect to focus voltage change.
Other representative disclosures having astigmator electrode structures in the lower end include U.S. Pat. Nos. 4,242,613 to Brambring et al; 4,366,414 to Hatayama et al; and 4,629,933 to Bijma et al. Koshigoe in U.S. Pat. No. 4,641,058 discloses means for forming an asymetrical lens in both the prefocusing lens and in the main focus lens.
An in-line gun (the "DAF" gun) that is said to provide dynamic astigmatism and focus correction is described in a journal article by Suzuki et al. The focus electrode of a bipotential-type gun is split into a lower section adjacent to prefocusing lens, and an upper section adjacent to an accelerating anode. The beam-passing apertures in the opposed faces of the two sections are rectangular--the apertures in the ower section are vertically oriented, and those in the upper section are transverse to those in the lower section. The focus voltage is applied to the lower section, and a combination of the focus voltage and a dynamic voltage that is caused to vary with the excursion of the beams across the screen, is applied to the upper section. When the dynamic voltage is increased from the level of the focusing voltage, an electric quadrupole field is produced between the lower section and the upper section which is alleged to counter the astigmatizing field of the self-converging yoke. The amount of counter-astigmatizing is a function of the location of the beams on the screen--the farther from center screen, the greater the counter-astigmatizing effect. The lens formed between the upper section and the accelerating anode is an OLF--"overlapping field" lens. The use of OLF lens in this gun configuration is said to provide a larger apparent lens diameter with consequent lower magnification of the beam spots at center screen. However, the influence of the OLF lens is inherently astigmatizing, which distorts the beams at the center. Nor does the DAF gun have any provision for dynamic convergence other than the self-converging yoke. ("Progressive-Scanned 33-in. 110.degree. Flat-Square Color CRT." Suzuki et al. SID 87 Digest, pp 166-169.) | {
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This invention relates to thermally developable materials containing certain backside conductive layers. In particular, the invention relates to thermographic and photothermographic materials containing metal antimonate conductive particles in backside conductive layers that are buried beneath a protective overcoat. The invention also relates to methods of imaging the thermally developable materials.
Silver-containing thermographic and photothermographic imaging materials (that is, thermally developable imaging materials) that are imaged and/or developed using heat and without liquid processing have been known in the art for many years.
Silver-containing thermographic imaging materials are non-photosensitive materials that are used in a recording process wherein images are generated by the use of thermal energy. These materials generally comprise a support having disposed thereon (a) a relatively or completely non-photosensitive source of reducible silver ions, (b) a reducing composition (usually including a developer) for the reducible silver ions, and (c) a suitable hydrophilic or hydrophobic binder.
In a typical thermographic construction, the image-forming layers are based on silver salts of long chain fatty acids. Typically, the preferred non-photosensitive reducible silver source is a silver salt of a long chain aliphatic carboxylic acid having from 10 to 30 carbon atoms. The silver salt of behenic acid or mixtures of acids of similar molecular weight are generally used. At elevated temperatures, the silver of the silver carboxylate is reduced by a reducing agent for silver ion such as methyl gallate, hydroquinone, substituted-hydroquinones, hindered phenols, catechols, pyrogallol, ascorbic acid, and ascorbic acid derivatives, whereby an image of elemental silver is formed. Some thermographic constructions are imaged by contacting them with the thermal head of a thermographic recording apparatus such as a thermal printer or thermal facsimile. In such constructions, an anti-stick layer is coated on top of the imaging layer to prevent sticking of the thermographic construction to the thermal head of the apparatus utilized. The resulting thermographic construction is then heated to an elevated temperature, typically in the range of from about 60 to about 225xc2x0 C., resulting in the formation of an image.
Silver-containing photothermographic imaging materials are photosensitive materials that are used in a recording process wherein an image is formed by imagewise exposure of the photothermographic material to specific electromagnetic radiation (for example, X-radiation, or ultraviolet, visible, or infrared radiation) and developed by the use of thermal energy. These materials, also known as xe2x80x9cdry silverxe2x80x9d materials, generally comprise a support having coated thereon: (a) a photocatalyst (that is, a photosensitive compound such as silver halide) that upon such exposure provides a latent image in exposed grains that are capable of acting as a catalyst for the subsequent formation of a silver image in a development step, (b) a relatively or completely non-photosensitive source of reducible silver ions, (c) a reducing composition (usually including a developer) for the reducible silver ions, and (d) a hydrophilic or hydrophobic binder. The latent image is then developed by application of thermal energy.
In such materials, the photosensitive catalyst is generally a photographic type photosensitive silver halide that is considered to be in catalytic proximity to the non-photosensitive source of reducible silver ions. Catalytic proximity requires intimate physical association of these two components either prior to or during the thermal image development process so that when silver atoms (Ag0)n, also known as silver specks, clusters, nuclei or latent image, are generated by irradiation or light exposure of the photosensitive silver halide, those silver atoms are able to catalyze the reduction of the reducible silver ions within a catalytic sphere of influence around the silver atoms [D. H. Klosterboer, Imaging Processes and Materials, (Neblette""s Eighth Edition), J. Sturge, V. Walworth, and A. Shepp, Eds., Van Nostrand-Reinhold, New York, 1989, Chapter 9, pp. 279-291]. It has long been understood that silver atoms act as a catalyst for the reduction of silver ions, and that the photosensitive silver halide can be placed in catalytic proximity with the non-photosensitive source of reducible silver ions in a number of different ways (see, for example, Research Disclosure, June 1978, item 17029). Other photosensitive materials, such as titanium dioxide, cadmium sulfide, and zinc oxide have also been reported to be useful in place of silver halide as the photocatalyst in photothermographic materials [see for example, Shepard, J. Appl. Photog. Eng. 1982, 8(5), 210-212, Shigeo et al., Nippon Kagaku Kaishi, 1994, 11, 992-997, and FR 2,254,047 (Robillard)].
The photosensitive silver halide may be made xe2x80x9cin-situ,xe2x80x9d for example by mixing an organic or inorganic halide-containing source with a source of reducible silver ions to achieve partial metathesis and thus causing the in-situ formation of silver halide (AgX) grains throughout the silver source [see, for example, U.S. Pat. No. 3,457,075 (Morgan et al.)]. In addition, photosensitive silver halides and sources of reducible silver ions can be coprecipitated [see Yu. E. Usanov et al., J. Imag. Sci. Tech. 1996, 40, 104]. Alternatively, a portion of the reducible silver ions can be completely converted to silver halide, and that portion can be added back to the source of reducible silver ions (see Yu. E. Usanov et al., International Conference on Imaging Science, Sep. 7-11, 1998, pp. 67-70).
The silver halide may also be xe2x80x9cpreformedxe2x80x9d and prepared by an xe2x80x9cex-situ xe2x80x9d process whereby the silver halide (AgX) grains are prepared and grown separately. With this technique, one has the possibility of controlling the grain size, grain size distribution, dopant levels, and composition much more precisely, so that one can impart more specific properties to both the silver halide grains and the photothermographic material. The preformed silver halide grains may be introduced prior to and be present during the formation of the source of reducible silver ions. Co-precipitation of the silver halide and the source of reducible silver ions provides a more intimate mixture of the two materials [see for example U.S. Pat. No. 3,839,049 (Simons)]. Alternatively, the preformed silver halide grains may be added to and physically mixed with the source of reducible silver ions.
The non-photosensitive source of reducible silver ions is a material that contains reducible silver ions. Typically, the preferred non-photosensitive source of reducible silver ions is a silver salt of a long chain aliphatic carboxylic acid having from 10 to 30 carbon atoms, or mixtures of such salts. Such acids are also known as xe2x80x9cfatty acidsxe2x80x9d or xe2x80x9cfatty carboxylic acidsxe2x80x9d. Silver salts of other organic acids or other organic compounds, such as silver imidazoles, silver tetrazoles, silver benzotriazoles, silver benzotetrazoles, silver benzothiazoles and silver acetylides may also be used. U.S. Pat. No. 4,260,677 (Winslow et al.) discloses the use of complexes of various inorganic or organic silver salts.
In photothermographic materials, exposure of the photographic silver halide to light produces small clusters containing silver atoms (Ag0)n. The imagewise distribution of these clusters, known in the art as a latent image, is generally not visible by ordinary means. Thus, the photosensitive material must be further developed to produce a visible image. This is accomplished by the reduction of silver ions that are in catalytic proximity to silver halide grains bearing the silver-containing clusters of the latent image. This produces a black-and-white image. The non-photosensitive silver source is catalytically reduced to form the visible black-and-white negative image while much of the silver halide, generally, remains as silver halide and is not reduced.
In photothermographic materials, the reducing agent for the reducible silver ions, often referred to as a xe2x80x9cdeveloper,xe2x80x9d may be any compound that, in the presence of the latent image, can reduce silver ion to metallic silver and is preferably of relatively low activity until it is heated to a temperature sufficient to cause the reaction. A wide variety of classes of compounds have been disclosed in the literature that function as developers for photothermographic materials. At elevated temperatures, the reducible silver ions are reduced by the reducing agent. In photothermographic materials, upon heating, this reaction occurs preferentially in the regions surrounding the latent image. This reaction produces a negative image of metallic silver having a color that ranges from yellow to deep black depending upon the presence of toning agents and other components in the imaging layer(s).
The imaging arts have long recognized that the field of photothermography is clearly distinct from that of photography. Photothermographic materials differ significantly from conventional silver halide photographic materials that require processing with aqueous processing solutions.
As noted above, in photothermographic imaging materials, a visible image is created by heat as a result of the reaction of a developer incorporated within the material. Heating at 50xc2x0 C. or more is essential for this dry development. In contrast, conventional photographic imaging materials require processing in aqueous processing baths at more moderate temperatures (from 30xc2x0 C. to 50xc2x0 C.) to provide a visible image.
In photothermographic materials, only a small amount of silver halide is used to capture light and a non-photosensitive source of reducible silver ions (for example a silver carboxylate) is used to generate the visible image using thermal development. Thus, the imaged photosensitive silver halide serves as a catalyst for the physical development process involving the non-photosensitive source of reducible silver ions and the incorporated reducing agent. In contrast, conventional wet-processed, black-and-white photographic materials use only one form of silver (that is, silver halide) that, upon chemical development, is itself at least partially converted into the silver image, or that upon physical development requires addition of an external silver source (or other reducible metal ions that form black images upon reduction to the corresponding metal). Thus, photothermographic materials require an amount of silver halide per unit area that is only a fraction of that used in conventional wet-processed photographic materials.
In photothermographic materials, all of the xe2x80x9cchemistryxe2x80x9d for imaging is incorporated within the material itself. For example, such materials include a developer (that is, a reducing agent for the reducible silver ions) while conventional photographic materials usually do not. Even in so-called xe2x80x9cinstant photography,xe2x80x9d the developer chemistry is physically separated from the photosensitive silver halide until development is desired. The incorporation of the developer into photothermographic materials can lead to increased formation of various types of xe2x80x9cfogxe2x80x9d or other undesirable sensitometric side effects. Therefore, much effort has gone into the preparation and manufacture of photothermographic materials to minimize these problems during the preparation of the photothermographic emulsion as well as during coating, use, storage, and post-processing handling.
Moreover, in photothermographic materials, the unexposed silver halide generally remains intact after development and the material must be stabilized against further imaging and development. In contrast, silver halide is removed from conventional photographic materials after solution development to prevent further imaging (that is in the aqueous fixing step).
In photothermographic materials, the binder is capable of wide variation and a number of binders (both hydrophilic and hydrophobic) are useful. In contrast, conventional photographic materials are limited almost exclusively to hydrophilic colloidal binders such as gelatin.
Because photothermographic materials require dry thermal processing, they present distinctly different problems and require different materials in manufacture and use, compared to conventional, wet-processed silver halide photographic materials. Additives that have one effect in conventional silver halide photographic materials may behave quite differently when incorporated in photothermographic materials where the underlying chemistry is significantly more complex. The incorporation of such additives as, for example, stabilizers, antifoggants, speed enhancers, supersensitizers, and spectral and chemical sensitizers in conventional photographic materials is not predictive of whether such additives will prove beneficial or detrimental in photothermographic materials. For example, it is not uncommon for a photographic antifoggant useful in conventional photographic materials to cause various types of fog when incorporated into photothermographic materials, or for supersensitizers that are effective in photographic materials to be inactive in photothermographic materials.
These and other distinctions between photothermographic and photographic materials are described in Imaging Processes and Materials (Neblette""s Eighth Edition), noted above, Unconventional Imaging Processes, E. Brinckman et al. (Eds.), The Focal Press, London and New York, 1978, pp. 74-75, in Zou et al., J. Imaging Sci. Technol. 1996, 40, pp. 94-103, and in M. R. V. Sahyun, J. Imaging Sci. Technol. 1998, 42, 23.
Many of the chemicals used to make supports or supported layers in thermally developable materials have electrically insulating properties, and electrostatic charges frequently build up on the materials during manufacture, packaging, and use. The accumulated charges can cause various problems. For example, in photothermographic materials containing photosensitive silver halides, accumulated electrostatic charge can generate light to which the silver halides are sensitive. This may result in imaging defects that are a particular problem where the images are used for medical diagnosis.
Build-up of electrostatic charge can also cause sheets of imageable material to stick together causing misfeeds and jamming within processing equipment. Additionally, accumulated electrostatic charge can attract dust or other particulate matter to the imageable material, thereby requiring more cleaning means so transport through the processing equipment and image quality of the material are not diminished.
Build-up of electrostatic charge also makes handling of developed sheets of imaged material more difficult. For example, a radiologist desires a static free sheet for viewing on the light boxes. This problem can be particularly severe when reviewing an imaged film that has been stored for a lengthy period of time because many antistatic materials loose their effectiveness over time.
In general, electrostatic charge is related to surface resistivity (measured in ohm/sq) and charge level. While electrostatic charge control agents (or antistatic agents) can be included in any layer of an imaging material, the accumulation of electrostatic charge can be prevented by reducing the surface resistivity or by lowering the charge level. This is usually done by including charge control agents in surface layers. Such surface layers may include what are known as xe2x80x9cprotectivexe2x80x9d overcoats or various backing layers in imaging materials. In thermographic and photothermographic materials, charge control agents may be incorporated into backing layers (such as antihalation layers of photothermographic materials) that are on the opposite side of the support as the imaging layers.
A wide variety of charge control agents, both inorganic and organic, have been devised and used for electrostatic charge control and numerous publications describe such agents. Some charge control agents are designed to increase surface layer conductivity while others are designed to control the generation of surface electrostatic charge.
U.S. Pat. No. 5,340,676 (Anderson et al.) describes the use of various metal oxides in conductive layers of various types of imaging elements. U.S. Published Application 2001-0055490 (Oyamada) describes the use of similar metal oxides dispersed in one or more binders on the backside layers of thermally developable materials.
Fine particle metal antimonates are used in conductive layers of imaging elements including thermal imaging elements described in U.S. Pat. No. 5,368,995 (Christian et al.) and U.S. Pat. No. 5,457,013 (Christian et al.). Various binders can be used in these conductive layers that can be located in various locations in the elements.
U.S. Pat. No. 5,731,119 (Eichorst et al.) describes the use of acicular metal oxides in conductive layers and further describes an antistatic composition containing granular zinc antimonate in a polyurethane binder.
U.S. Pat. No. 6,355,405 (Ludemann et al.) describes thermally developable materials that include adhesion-promoting layers on either side of the support. These adhesion-promoting layers are usually very thin, include specific mixtures of polymers to provide the adhesion function, and are also known as xe2x80x9ccarrierxe2x80x9d layers. These layers can have a variety of other functions and may include materials that may improve coatability or adhesion, antihalation dyes, crosslinking agents (such as diisocyanates), surfactants and shelf-aging promoters.
Despite the considerable research and knowledge in the art relating to the use of various conductive compositions and imaging materials, there remains a need for conductive compositions that can be used on the backside of thermally developable imaging materials underneath the protective overcoats to provide improved shelf keeping properties and high conductivity.
The present invention provides a thermally developable material that comprises a support having on one side thereof, one or more thermally developable imaging layers comprising a binder and in reactive association, a non-photosensitive source of reducible silver ions, and a reducing agent composition for the non-photosensitive source reducible silver ions, and
having disposed on the backside of the support:
a) a first layer comprising a film-forming polymer, and
b) interposed between the support and the first layer and directly adhering the first layer to the support, a non-imaging backside conductive layer comprising non-acicular metal antimonate particles in a mixture of two or more polymers that include a first polymer serving to promote adhesion of the conductive layer directly to the support, and a second polymer that is different than and forms a single phase mixture with the first polymer,
wherein the film-forming polymer of the first layer and the second polymer of the conductive layer are the same or different polyvinyl acetal resins, polyester resins, cellulosic polymers, maleic anhydride-ester copolymers, or vinyl polymers.
Thus, in some embodiments, this invention provides a photothermographic material that comprises a support having on one side thereof, one or more thermally developable imaging layers comprising a binder and in reactive association, a photosensitive silver halide, a non-photosensitive source of reducible silver ions, and a reducing composition for the non-photosensitive source reducible silver ions, and
having disposed on the backside of the support:
a) a first layer comprising a film-forming polymer, and
b) interposed between the support and the first layer and directly adhering the first layer to the support, a non-imaging backside conductive layer comprising non-acicular metal antimonate particles in a mixture of two or more polymers that include a first polymer serving to promote adhesion of the backside conductive layer directly to the support, and a second polymer that is different than and forms a single phase mixture with the first polymer,
wherein the film-forming polymer of the first layer and the second polymer of the backside conductive layer are the same or different polyvinyl acetal resins, polyester resins, cellulosic polymers, maleic anhydride-ester copolymers, or vinyl polymers.
In one preferred embodiment, the present invention provides a black-and-white photothermographic material that comprises a transparent polymeric support having on one side thereof one or more thermally developable imaging layers comprising predominantly one or more hydrophobic binders including at least polyvinyl butyral, and in reactive association, a preformed photosensitive silver bromide or silver iodobromide present as tabular and/or cubic grains, a non-photosensitive source of reducible silver ions that includes one or more silver aliphatic carboxylates at least one of which is silver behenate, a reducing agent composition for the non-photosensitive source reducible silver ions comprising a hindered phenol or mixture thereof, and a protective layer disposed over the one or more thermally developable imaging layers, and
having disposed on the backside of the support:
a) a backside protective layer comprising a film-forming polymer that is cellulose acetate butyrate, and
b) interposed between the support and the backside protective layer and directly adhering the backside protective layer to the support, a non-imaging backside conductive layer comprising non-acicular metal antimonate particles in a mixture of two or more polymers that include a first polymer serving to promote adhesion of the backside conductive layer directly to the support, and a second polymer that is different than and forms a single phase mixture with the first polymer,
wherein the first polymer of the backside conductive layer is a polyester and the second polymer of the backside conductive layer is cellulose acetate butyrate, and
the non-acicular metal antimonate particles are composed of ZnSb2O6 and comprise from about 40 to about 55% by weight and are present in the backside conductive layer in an amount of from about 0.05 to about 2 g/m .
In another preferred embodiment, the present invention provides a black-and-white thermographic material that comprises a transparent polymeric support having on one side thereof one or more thermally developable imaging layers comprising predominantly one or more hydrophobic binders including at least polyvinyl butyral, and in reactive association, a non-photosensitive source of reducible silver ions that includes one or more silver aliphatic carboxylates at least one of which is silver behenate, a reducing agent composition for the non-photosensitive source reducible silver ions comprising an aromatic di- and tri-hydroxy compound having at least two hydroxy groups in ortho- or para-relationship on the same aromatic nucleus or mixture thereof, and a protective layer disposed over the one or more thermally developable imaging layers, and
having disposed on the backside of the support:
a) a backside protective layer comprising a film-forming polymer that is cellulose acetate butyrate, and
b) interposed between the support and the backside protective layer and directly adhering the backside protective layer to the support, a non-imaging backside conductive layer comprising non-acicular metal antimonate particles in a mixture of two or more polymers that include a first polymer serving to promote adhesion of the backside conductive layer directly to the support, and a second polymer that is different than and forms a single phase mixture with the first polymer,
wherein the first polymer of the backside conductive layer is a polyester and the second polymer of the backside conductive layer is polyvinyl butyral or cellulose acetate butyrate and
the non-acicular metal antimonate particles are composed of ZnSb2O6 and comprise from about 40 to about 55% by weight of the buried backside conductive layer and are present in the conductive layer in an amount of from about 0.05 to about 2 g/m2.
The present invention provides a thermally developable material that comprises a support having on one side thereof, one or more thermally developable imaging layers comprising a binder and in reactive association, a non-photosensitive source of reducible silver ions, and a reducing agent composition for the non-photosensitive source reducible silver ions, and
having disposed on the backside of the support:
a) a first layer comprising a film-forming polymer,
b) a second layer directly adhered to the support, comprising a mixture of two or more polymers that includes a first polymer serving to promote adhesion of the second layer directly to the support, and a second polymer that is different than and forms a single phase mixture with the first polymer, and
c) interposed between the first layer and the second layer, a non-imaging backside conductive layer comprising non-acicular metal antimonate particles in a polymer serving to promote adhesion of the backside conductive layer directly to the first and second layers,
wherein the film-forming polymer of the first layer, the polymer of the conductive layer, and the second polymer of the second layer are the same or different polyvinyl acetal resins, polyester resins, cellulosic polymers, maleic anhydride-ester copolymers, or vinyl polymers.
The present invention provides a thermally developable material that comprises a support having on one side thereof, one or more thermally developable imaging layers comprising a binder and in reactive association, a non-photosensitive source of reducible silver ions, and a reducing agent composition for the non-photosensitive source reducible silver ions, and
having disposed on the backside of the support:
a) a first layer comprising a film-forming polymer,
b) a second layer directly adhered to the support, comprising a first polymer, and
c) interposed between the first layer and the second layer, a non-imaging backside conductive layer comprising non-acicular metal antimonate particles in a mixture of two or more polymers that includes the first polymer that serves to promote adhesion to the second layer, and a second polymer that is different than and forms a single phase mixture with the first polymer, and serves to promote adhesion to the first layer,
wherein the film-forming polymer of the first layer and one of the two or more polymers of the backside conductive layer are the same or different polyvinyl acetal resins, polyester resins, cellulosic polymers, maleic anhydride-ester copolymers, or vinyl polymers.
Further, the present invention provides a method of forming a visible image comprising:
a) imagewise exposing a photothermographic material of the present invention to electromagnetic radiation to form a latent image,
b) simultaneously or sequentially, heating the exposed photothermographic material to develop the latent image into a visible image.
In embodiments wherein the thermally developable material of the present invention is a thermographic material, a method of forming a visible image comprises thermal imaging of the thermally developable material.
In some embodiments wherein the thermographic or photothermographic material comprises a transparent support, the image-forming method further comprises:
c) positioning the exposed and heat-developed photothermographic material with the visible image thereon between a source of imaging radiation and an imageable material that is sensitive to the imaging radiation, and
d) thereafter exposing the imageable material to the imaging radiation through the visible image in the exposed and heat-developed photothermographic material to provide an image in the imageable material.
The present invention provides a number of advantages with the use of specific metal antimonates on the backside of the thermally developable materials. More specifically, the backside conductive layer is located underneath other layers such as an outermost protective layer so the conductive layer provides both conductivity as well as adhesion while the other layers can be designed with other properties. Since the conductive layer is xe2x80x9cburiedxe2x80x9d under the other layers, it is protected from dirt, dust, and fingerprints. The other layer (identified herein as the xe2x80x9cfirstxe2x80x9d layer) can be composed of different but xe2x80x9ccompatiblexe2x80x9d polymers and provide antihalation, physical and chemical protection and improved film transport.
Moreover, we have found that if the backside conductive layer is xe2x80x9cburied,xe2x80x9d the efficiency of the metal antimonate particles is improved. That is, fewer conductive particles are needed than when they are incorporated into the outermost layer. Also, by controlling the thickness of, or the amount of the metal antimonate in this xe2x80x9cburiedxe2x80x9d layer, the conductivity of the layer can be more readily adjusted. Additionally, when the backside conductive layer is xe2x80x9cburied,xe2x80x9d lower Dmin values can be obtained. Furthermore, use of metal antimonate particles in a xe2x80x9cburiedxe2x80x9d backside conductive layer has been found to reduce penetration of superposed layers into the coating slot of the xe2x80x9cburiedxe2x80x9d backside conductive layer during slide coating.
The thermally developable materials of this invention include both thermographic and photothermographic materials. While the following discussion will often be directed primarily to the preferred photothermographic embodiments, it would be readily understood by one skilled in the imaging arts that thermographic materials can be similarly constructed (using one or more imaging layers) and used to provide black-and-white or color images using non-photosensitive silver salts, reducing compositions, binders, and other components known to be useful in such embodiments. In both thermographic and photothermographic materials, the non-acicular metal antimonate particles described herein are generally incorporated into a separate conductive (xe2x80x9cantistaticxe2x80x9d) layer on at least the backside and optionally on both sides of the support.
The thermographic and photothermographic materials of this invention can be used in black-and-white or color thermography or photothermography and in electronically generated black-and-white or color hardcopy recording. They can be used in microfilm applications, in radiographic imaging (for example digital medical imaging), X-ray radiography, and in industrial radiography. Furthermore, the absorbance of these thermographic and photothermographic materials between 350 and 450 nm is desirably low (less than 0.5), to permit their use in the graphic arts area (for example, imagesetting and phototypesetting), in the manufacture of printing plates, in contact printing, in duplicating (xe2x80x9cdupingxe2x80x9d), and in proofing.
The thermographic and photothermographic materials of this invention are particularly useful for medical imaging of human or animal subjects in response to visible or X-radiation. Such applications include, but are not limited to, thoracic imaging, mammography, dental imaging, orthopedic imaging, general medical radiography, therapeutic radiography, veterinary radiography, and auto-radiography. When used with X-radiation, the photothermographic materials of this invention may be used in combination with one or more phosphor intensifying screens, with phosphors incorporated within the photothermographic emulsion, or with a combination thereof. The materials of this invention are also useful for non-medical uses of visible or X-radiation (such as X-ray lithography and industrial radiography).
The photothermographic materials of this invention can be made sensitive to radiation of any suitable wavelength. Thus, in some embodiments, the materials are sensitive at ultraviolet, visible, infrared or near infrared wavelengths, of the electromagnetic spectrum. In preferred embodiments, the materials are sensitive to radiation greater than 700 nm (and generally up to 1150 xcexcm). In other embodiments they are sensitive to X-radiation. Increased sensitivity to a particular region of the spectrum is imparted through the use of various sensitizing dyes.
The photothermographic materials of this invention are also useful for non-medical uses of visible or X-radiation (such as X-ray lithography and industrial radiography). In such imaging applications, it is often desirable that the photothermographic materials be xe2x80x9cdouble-sided.xe2x80x9d
In the photothermographic materials of this invention, the components needed for imaging can be in one or more thermally developable layers on one side (xe2x80x9cfrontsidexe2x80x9d) of the support. The layer(s) that contain the photosensitive photocatalyst (such as a photosensitive silver halide in photothermographic materials) or non-photosensitive source of reducible silver ions, or both, are referred to herein as photothermographic emulsion layer(s). The photocatalyst and the non-photosensitive source of reducible silver ions are in catalytic proximity (that is, in reactive association with each other) and preferably are in the same emulsion layer.
Similarly, in the thermographic materials of this invention, the components needed for imaging can be in one or more layers. The layer(s) that contain the non-photosensitive source of reducible silver ions are referred to herein as thermographic emulsion layer(s).
Where the materials contain imaging layers on one side of the support only, various non-imaging layers are usually disposed on the xe2x80x9cbacksidexe2x80x9d (non-emulsion or non-imaging side) of the materials, including at least one conductive layer described herein, and optionally antihalation layer(s), protective layers, and transport enabling layers.
In such instances, various non-imaging layers can also be disposed on the xe2x80x9cfrontsidexe2x80x9d or imaging or emulsion side of the support, including protective topcoat layers, primer layers, interlayers, opacifying layers, antistatic layers, antihalation layers, acutance layers, auxiliary layers, and other layers readily apparent to one skilled in the art.
For some applications it may be useful that the photothermographic materials be xe2x80x9cdouble-sidedxe2x80x9d and have photothermographic coatings on both sides of the support. In such constructions each side can also include one or more protective topcoat layers, primer layers, interlayers, antistatic layers, acutance layers, auxiliary layers, anti-crossover layers, and other layers readily apparent to one skilled in the art.
When the thermographic and photothermographic materials of this invention are heat-developed as described below in a substantially water-free condition after, or simultaneously with, imagewise exposure, a silver image (preferably a black-and-white silver image) is obtained.
As used herein:
In the descriptions of the photothermographic materials of the present invention, xe2x80x9caxe2x80x9d or xe2x80x9canxe2x80x9d component refers to xe2x80x9cat least onexe2x80x9d of that component (for example, the specific metal antimonates in the backside conductive layer).
The term xe2x80x9cpolymerxe2x80x9d when referring to polymeric materials is defined to include homopolymers, copolymers and terpolymers.
Heating in a substantially water-free condition as used herein, means heating at a temperature of from about 50xc2x0 C. to about 250xc2x0 C. with little more than ambient water vapor present. The term xe2x80x9csubstantially water-free conditionxe2x80x9d means that the reaction system is approximately in equilibrium with water in the air and water for inducing or promoting the reaction is not particularly or positively supplied from the exterior to the material. Such a condition is described in T. H. James, The Theory of the Photographic Process, Fourth Edition, Eastman Kodak Company, Rochester, N.Y., 1977, p. 374.
xe2x80x9cPhotothermographic material(s)xe2x80x9d means a construction comprising at least one photothermographic emulsion layer or a photothermographic set of layers, wherein the photosensitive silver halide and the source of reducible silver ions are in one layer and the other essential components or desirable additives are distributed, as desired, in the same layer or in an adjacent coating layer, as well as any supports, topcoat layers, image-receiving layers, blocking layers, antihalation layers, subbing or priming layers. These materials also include multilayer constructions in which one or more imaging components are in different layers, but are in xe2x80x9creactive associationxe2x80x9d so that they readily come into contact with each other during imaging and/or development. For example, one layer can include the non-photosensitive source of reducible silver ions and another layer can include the reducing composition, but the two reactive components are in reactive association with each other.
xe2x80x9cThermographic materialsxe2x80x9d are similarly defined except that no photosensitive silver halide is present.
When used in photothermography, the term, xe2x80x9cimagewise exposingxe2x80x9d or xe2x80x9cimagewise exposurexe2x80x9d means that the material is imaged using any exposure means that provides a latent image using electromagnetic radiation. This includes, for example, by analog exposure where an image is formed by projection onto the photosensitive material as well as by digital exposure where the image is formed one pixel at a time such as by modulation of scanning laser radiation.
When used in thermography, the term, xe2x80x9cimagewise exposingxe2x80x9d or xe2x80x9cimagewise exposurexe2x80x9d means that the material is imaged using any means that provides an image using heat. This includes, for example, by analog exposure where an image is formed by differential contact heating through a mask using a thermal blanket or infrared heat source, as well as by digital exposure where the image is formed one pixel at a time such as by modulation of thermal print-heads.
xe2x80x9cCatalytic proximityxe2x80x9d or xe2x80x9creactive associationxe2x80x9d means that the materials are in the same layer or in adjacent layers so that they readily come into contact with each other during thermal imaging and development.
xe2x80x9cEmulsion layer,xe2x80x9d xe2x80x9cimaging layer,xe2x80x9d xe2x80x9cthermographic emulsion layer,xe2x80x9d or xe2x80x9cphotothermographic emulsion layer,xe2x80x9d means a layer of a thermographic or photothermographic material that contains the photosensitive silver halide (when used) and/or non-photosensitive source of reducible silver ions. It can also mean a layer of the thermographic or photothermographic material that contains, in addition to the photosensitive silver halide (when used) and/or non-photosensitive source of reducible ions, additional essential components and/or desirable additives. These layers are usually on what is known as the xe2x80x9cfrontsidexe2x80x9d of the support.
xe2x80x9cPhotocatalystxe2x80x9d means a photosensitive compound such as silver halide that, upon exposure to radiation, provides a compound that is capable of acting as a catalyst for the subsequent development of the image-forming material.
Some of the materials used herein are provided as a solution or dispersion. The term xe2x80x9cactive ingredientxe2x80x9d or xe2x80x9cactive solidsxe2x80x9d means the amount or the percentage of the desired material contained in a sample. All amounts listed herein are the amount of active ingredient added unless otherwise specified.
xe2x80x9cUltraviolet region of the spectrumxe2x80x9d refers to that region of the spectrum less than or equal to 410 nm, and preferably from about 100 nm to about 410 nm, although parts of these ranges may be visible to the naked human eye. More preferably, the ultraviolet region of the spectrum is the region of from about 190 to about 405 nm.
xe2x80x9cVisible region of the spectrumxe2x80x9d refers to that region of the spectrum of from about 400 nm to about 700 nm.
xe2x80x9cShort wavelength visible region of the spectrumxe2x80x9d refers to that region of the spectrum of from about 400 nm to about 450 nm.
xe2x80x9cRed region of the spectrumxe2x80x9d refers to that region of the spectrum of from about 600 nm to about 700 nm.
xe2x80x9cInfrared region of the spectrumxe2x80x9d refers to that region of the spectrum of from about 700 nm to about 1400 nm.
xe2x80x9cNon-photosensitivexe2x80x9d means not intentionally light sensitive.
The sensitometric terms xe2x80x9cphotospeed,xe2x80x9d xe2x80x9cspeed,xe2x80x9d or xe2x80x9cphotographic speedxe2x80x9d (also known as sensitivity), absorbance, contrast, Dmin, and Dmax have conventional definitions known, in the imaging arts. In photothermographic materials, Dmin is considered herein as image density achieved when the photothermographic material is thermally developed without prior exposure to radiation. It is the average of eight lowest density values on the exposed side of the fiducial mark. In thermographic materials, Dmin is considered herein as image density in the non-thermally imaged areas of the thermographic material.
The sensitometric term absorbance is another term for optical density (OD).
xe2x80x9cTransparentxe2x80x9d means capable of transmitting visible light or imaging radiation without appreciable scattering or absorption.
As used herein, the phrase xe2x80x9corganic silver coordinating ligandxe2x80x9d refers to an organic molecule capable of forming a bond with a silver atom. Although the compounds so formed are technically silver coordination compounds they are also often referred to as silver salts.
The terms xe2x80x9cdouble-sidedxe2x80x9d and xe2x80x9cdouble-faced coatingxe2x80x9d are used to define photothermographic materials having one or more of the same or different thermally developable emulsion layers disposed on both sides (front and back) of the support.
The term xe2x80x9cburied layerxe2x80x9d means that there is at least one other layer disposed over the backside conductive layer(s).
In the compounds described herein, no particular double bond geometry (for example, cis or trans) is intended by the structures drawn. Similarly, in compounds having alternating single and double bonds and localized charges are drawn as a formalism. In reality, both electron and charge delocalization exists throughout the conjugated chain.
As is well understood in this art, for the chemical compounds herein described, substitution is not only tolerated, but is often advisable and various substituents are anticipated on the compounds used in the present invention unless otherwise stated. Thus, when a compound is referred to as xe2x80x9chaving the structurexe2x80x9d of a given formula, any substitution that does not alter the bond structure of the formula or the shown atoms within that structure is included within the formula, unless such substitution is specifically excluded by language (such as xe2x80x9cfree of carboxy-substituted alkylxe2x80x9d). For example, where a benzene ring structure is shown (including fused ring structures), substituent groups may be placed on the benzene ring structure, but the atoms making up the benzene ring structure may not be replaced.
As a means of simplifying the discussion and recitation of certain substituent groups, the term xe2x80x9cgroupxe2x80x9d refers to chemical species that may be substituted as well as those that are not so substituted. Thus, the term xe2x80x9cgroup,xe2x80x9d such as xe2x80x9calkyl groupxe2x80x9d is intended to include not only pure hydrocarbon alkyl chains, such as methyl, ethyl, n-propyl, t-butyl, cyclohexyl, iso-octyl, and octadecyl, but also alkyl chains bearing substituents known in the art, such as hydroxyl, alkoxy, phenyl, halogen atoms (F, Cl, Br, and I), cyano, nitro, amino, and carboxy. For example, alkyl group includes ether and thioether groups (for example CH3xe2x80x94CH2xe2x80x94CH2xe2x80x94Oxe2x80x94CH2xe2x80x94 and CH3xe2x80x94CH2xe2x80x94CH2xe2x80x94Sxe2x80x94CH2xe2x80x94), haloalkyl, nitroalkyl, alkylcarboxy, carboxyalkyl, carboxamido, hydroxyalkyl, sulfoalkyl, and other groups readily apparent to one skilled in the art. Substituents that adversely react with other active ingredients, such as very strongly electrophilic or oxidizing substituents, would, of course, be excluded by the ordinarily skilled artisan as not being inert or harmless.
Research Disclosure is a publication of Kenneth Mason Publications Ltd., Dudley House, 12 North Street, Emsworth, Hampshire PO10 7DQ England. It is also available from Emsworth Design Inc., 147 West 24th Street, New York, N.Y. 10011.
Other aspects, advantages, and benefits of the present invention are apparent from the detailed description, examples, and claims provided in this application.
As noted above, the photothermographic materials of the present invention include one or more photocatalysts in the photothermographic emulsion layer(s). Useful photocatalysts are typically silver halides such as silver bromide, silver iodide, silver chloride, silver iodobromide, silver chlorobromoiodide, silver chlorobromide, and others readily apparent to one skilled in the art. Mixtures of silver halides can also be used in any suitable proportion. Silver bromide and silver bromoiodide are more preferred, with the latter silver halide generally having up to 10 mol % silver iodide. Typical techniques for preparing and precipitating silver halide grains are described in Research Disclosure, 1978, item 17643.
In some embodiments of aqueous-based photothermographic materials, higher amounts of iodide may be present in homogeneous photosensitive silver halide grains, and particularly from about 20 mol % up to the saturation limit of iodide as described, for example, in copending and commonly assigned U.S. Ser. No. 10/246,265 (filed Sep. 18, 2002 by Maskasky and Scaccia).
The shape of the photosensitive silver halide grains used in the present invention is in no way limited. The silver halide grains may have any crystalline habit including, but not limited to, cubic, octahedral, tetrahedral, orthorhombic, rhombic, dodecahedral, other polyhedral, tabular, laminar, twinned, or platelet morphologies and may have epitaxial growth of crystals thereon. If desired, a mixture of these crystals can be employed. Silver halide grains having cubic and tabular morphology are preferred.
The silver halide grains may have a uniform ratio of halide throughout. They may have a graded halide content, with a continuously varying ratio of, for example, silver bromide and silver iodide or they may be of the core-shell type, having a discrete core of one or more silver halides, and a discrete shell of one or more different silver halides. Core-shell silver halide grains useful in photothermographic materials and methods of preparing these materials are described for example in U.S. Pat. No. 5,382,504 (Shor et al.), incorporated herein by reference. Iridium and/or copper doped core-shell and non-core-shell grains are described in U.S. Pat. No. 5,434,043 (Zou et al.) and U.S. Pat. No. 5,939,249 (Zou), both incorporated herein by reference.
The photosensitive silver halide can be added to (or formed within) the emulsion layer(s) in any fashion as long as it is placed in catalytic proximity to the non-photosensitive source of reducible silver ions.
It is preferred that the silver halides be preformed and prepared by an ex-situ process. The silver halide grains prepared ex-situ may then be added to and physically mixed with the non-photosensitive source of reducible silver ions.
It is more preferable to form the source of reducible silver ions in the presence of ex-situ-prepared silver halide. In this process, the source of reducible silver ions, such as a long chain fatty acid silver carboxylate (commonly referred to as a silver xe2x80x9csoapxe2x80x9d), is formed in the presence of the preformed silver halide grains. Co-precipitation of the reducible source of silver ions in the presence of silver halide provides a more intimate mixture of the two materials [see, for example U.S. Pat. No. 3,839,049 (Simons)]. Materials of this type are often referred to as xe2x80x9cpreformed soaps.xe2x80x9d
The silver halide grains used in the imaging formulations can vary in average diameter of up to several micrometers (xcexcm) depending on their desired use. Preferred silver halide grains are those having an average particle size of from about 0.01 to about 1.5 xcexcm, more preferred are those having an average particle size of from about 0.03 to about 1.0 xcexcm, and most preferred are those having an average particle size of from about 0.05 to about 0.8 xcexcm. Those of ordinary skill in the art understand that there is a finite lower practical limit for silver halide grains that is partially dependent upon the wavelengths to which the grains are spectrally sensitized. Such a lower limit, for example, is typically from about 0.01 to about 0.005 xcexcm.
The average size of the photosensitive doped silver halide grains is expressed by the average diameter if the grains are spherical, and by the average of the diameters of equivalent circles for the projected images if the grains are cubic or in other non-spherical shapes.
Grain size may be determined by any of the methods commonly employed in the art for particle size measurement. Representative methods are described by in xe2x80x9cParticle Size Analysis,xe2x80x9d ASTM Symposium on Light Microscopy, R. P. Loveland, 1955, pp. 94-122, and in C. E. K. Mees and T. H. James, The Theory of the Photographic Process, Third Edition, Macmillan, New York, 1966, Chapter 2. Particle size measurements may be expressed in terms of the projected areas of grains or approximations of their diameters. These will provide reasonably accurate results if the grains of interest are substantially uniform in shape.
Preformed silver halide emulsions used in the material of this invention can be prepared by aqueous or organic processes and can be unwashed or washed to remove soluble salts. In the latter case, the soluble salts can be removed by ultrafiltration, by chill setting and leaching, or by washing the coagulum [for example, by the procedures described in U.S. Pat. No. 2,618,556 (Hewitson et al.), U.S. Pat. No. 2,614,928 (Yutzy et al.), U.S. Pat. No. 2,565,418 (Yackel), U.S. Pat. No. 3,241,969 (Hart et al.), and U.S. Pat. No. 2,489,341 (Waller et al.)].
It is also effective to use an in-situ process in which a halide-containing compound is added to an organic silver salt to partially convert the silver of the organic silver salt to silver halide. The halogen-containing compound can be inorganic (such as zinc bromide or lithium bromide) or organic (such as N-bromosuccinimide).
Mixtures of both preformed and in-situ generated silver halide may be used if desired.
Additional methods of preparing these silver halide and organic silver salts and manners of blending them are described in Research Disclosure, June 1978, item 17029, U.S. Pat. No. 3,700,458 (Lindholm), U.S. Pat. No. 4,076,539 (Ikenoue et al.), JP 49-013224 A, (Fuji), 50-017216 A (Fuji), and 51-042529 A (Fuji).
In some instances, it may be helpful to prepare the photosensitive silver halide grains in the presence of a hydroxytetraazaindene (such as 4-hydroxy-6-methyl-1,3,3a,7-tetraazaindene or an N-heterocyclic compound comprising at least one mercapto group (such as 1-phenyl-5-mercaptotetrazole) to provide increased photospeed. Details of this procedure are provided in U.S. Pat. No. 6,413,710B1 (Shor et al.), that is incorporated herein by reference.
The one or more light-sensitive silver halides used in the photothermographic materials of the present invention are preferably present in an amount of from about 0.005 to about 0.5 mole, more preferably from about 0.01 to about 0.25 mole, and most preferably from about 0.03 to about 0.15 mole, per mole of non-photosensitive source of reducible silver ions.
The photosensitive silver halides used in photothermographic features of the invention may be employed without modification. However, one or more conventional chemical sensitizers may be used in the preparation of the photosensitive silver halides to increase photospeed. Such compounds may contain sulfur, tellurium, or selenium, or may comprise a compound containing gold, platinum, palladium, ruthenium, rhodium, iridium, or combinations thereof, a reducing agent such as a tin halide or a combination of any of these. The details of these materials are provided for example, in T. H. James, The Theory of the Photographic Process, Fourth Edition, Eastman Kodak Company, Rochester, N.Y., 1977, Chapter 5, pp. 149-169. Suitable conventional chemical sensitization procedures are also described in U.S. Pat. No. 1,623,499 (Sheppard et al.), U.S. Pat. No. 2,399,083 (Waller et al.), U.S. Pat. No. 3,297,447 (McVeigh), U.S. Pat. No. 3,297,446 (Dunn), U.S. Pat. No. 5,049,485 (Deaton), U.S. Pat. No. 5,252,455 (Deaton), U.S. Pat. No. 5,391,727 (Deaton), U.S. Pat. No. 5,912,111 (Lok et al.), U.S. Pat. No. 5,759,761 (Lushington et al.), U.S. Pat. No. 6,296,998 (Eikenberry et al), and EP 0 915 371 A1 (Lok et al.), all of which are incorporated herein by reference.
In addition, mercaptotetrazoles and tetraazindenes as described in U.S. Pat. No. 5,691,127 (Daubendiek et al.), incorporated herein by reference, can be used as suitable addenda for tabular silver halide grains.
When used, sulfur sensitization is usually performed by adding a sulfur sensitizer and stirring the emulsion at an appropriate temperature for a predetermined time. Various sulfur compounds can be used. Some examples of sulfur sensitizers include thiosulfates, thioureas, thioamides, thiazoles, rhodanines, phosphine sulfides, thiohydantoins, 4-oxo-oxazolidine-2-thiones, dipolysulfides, mercapto compounds, polythionates, and elemental sulfur.
Certain tetrasubstituted thiourea compounds are also useful in the present invention. Such compounds are described, for example in U.S. Pat. No. 6,296,998 (Eikenberry et al.), U.S. Pat. No. 6,322,961 (Lam et al.) and U.S. Pat. No. 6,368,779 (Lynch et al.). Also useful are the tetrasubstituted middle chalcogen (that is, sulfur, selenium, and tellurium) thiourea compounds disclosed in U.S. Pat. No. 4,810,626 (Burgmaier et al.). All of the above patents are incorporated herein by reference.
The amount of the sulfur sensitizer to be added varies depending upon various conditions such as pH, temperature and grain size of silver halide at the time of chemical ripening, it is preferably from 10xe2x88x927 to 10xe2x88x922 mole per mole of silver halide, and more preferably from 10xe2x88x926 to 10xe2x80x34 mole.
In one preferred embodiment, chemical sensitization is achieved by oxidative decomposition of a sulfur-containing spectral sensitizing dye in the presence of a photothermographic emulsion. Such sensitization is described in U.S. Pat. No. 5,891,615 (Winslow et al.), incorporated herein by reference.
Still other useful chemical sensitizers include certain selenium-containing compounds. When used, selenium sensitization is usually performed by adding a selenium sensitizer and stirring the emulsion at an appropriate temperature for a predetermined time. Some specific examples of useful selenium compounds can be found in U.S. Pat. No. 5,158,892 (Sasaki et al.), U.S. Pat. No. 5,238,807 (Sasaki et al.), U.S. Pat. No. 5,942,384 (Arai et al.) and in co-pending and commonly assigned U.S. Ser. No. 10/082,516 (filed Feb. 25, 2002 by Lynch, Opatz, Gysling, and Simpson). All of the above documents are incorporated herein by reference.
Still other useful chemical sensitizers include certain tellurium-containing compounds. When used, tellurium sensitization is usually performed by adding a tellurium sensitizer and stirring the emulsion at an appropriate temperature for a predetermined time. Tellurium compounds for use as chemical sensitizers can be selected from those described in J. Chem. Soc,. Chem. Commun. 1980, 635, ibid., 1979, 1102, ibid., 1979, 645, J. Chem. Soc. Perkin. Trans, 1980, 1, 2191, The Chemistry of Organic Selenium and Tellurium Compounds, S. Patai and Z. Rappoport, Eds., Vol. 1 (1986), and Vol. 2 (1987), U.S. Pat. No. 1,623,499 (Sheppard et al.), U.S. Pat. No. 3,320,069 (Illingsworth), U.S. Pat. No. 3,772,031 (Berry et al.), U.S. Pat. No. 5,215,880 (Kojima et al.), U.S. Pat. No. 5,273,874 (Kojima et al.), U.S. Pat. No. 5,342,750 (Sasaki et al.), U.S. Pat. No. 5,677,120 (Lushington et al.), British Pat. No. 235,211 (Sheppard), British Pat. No. 1,121,496 (Halwig), British Pat. No. 1,295,462 (Hilson et al.), British Pat. No. 1,396,696 (Simons), JP-04-271341 A (Morio et al.), in co-pending and commonly assigned U.S. Published Application 2002-0164549 (Lynch et al.), and in co-pending and commonly assigned U.S. Ser. No. 09/923,039 (filed Aug. 6, 2001 by Gysling, Dickinson, Lelental, and Boettcher). All of the above documents are incorporated herein by reference.
The amount of the selenium or tellurium sensitizer used in the present invention varies depending on silver halide grains used or chemical ripening conditions. However, it is generally from 10xe2x88x928 to 10xe2x88x922 mole per mole of silver halide, preferably on the order of from 10xe2x88x927 to 10xe2x88x923 mole.
Noble metal sensitizers for use in the present invention include gold, platinum, palladium and iridium. Gold sensitization is particularly preferred.
When used, the gold sensitizer used for the gold sensitization of the silver halide emulsion used in the present invention may have an oxidation number of 1 or 3, and may be a gold compound commonly used as a gold sensitizer. U.S. Pat. No. 5,858,637 (Eshelman et al.) describes various Au (I) compounds that can be used as chemical sensitizers. Other useful gold compounds can be found in U.S. Pat. No. 5,759,761 (Lushington et al.). Useful combinations of gold (I) complexes and rapid sulfiding agents are described in U.S. Pat. No. 6,322,961 (Lam et al.). Combinations of gold (III) compounds and either sulfur- or tellurium-containing compounds are useful as chemical sensitizers and are described in U.S. Pat. No. 6,423,481 (Simpson et al.). All of the above references are incorporated herein by reference.
Reduction sensitization may also be used. Specific examples of compounds useful in reduction sensitization include, but are not limited to, stannous chloride, hydrazine ethanolamine, and thioureaoxide. Reduction sensitization may be performed by ripening the grains while keeping the emulsion at pH 7 or above, or at pAg 8.3 or less.
The chemical sensitizers can be used in making the silver halide emulsions in conventional amounts that generally depend upon the average size of the silver halide grains. Generally, the total amount is at least 10xe2x88x9210 mole per mole of total silver, and preferably from about 10xe2x88x928 to about 10xe2x88x922 mole per mole of total silver. The upper limit can vary depending upon the compound(s) used, the level of silver halide, and the average grain size and grain morphology, and would be readily determinable by one of ordinary skill in the art.
The photosensitive silver halides used in the photothermographic features of the invention may be spectrally sensitized with various spectral sensitizing dyes that are known to enhance silver halide sensitivity to ultraviolet, visible, and/or infrared radiation. Non-limiting examples of sensitizing dyes that can be employed include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, and hemioxanol dyes. Cyanine dyes, merocyanine dyes and complex merocyanine dyes are particularly useful. Spectral sensitizing dyes are chosen for optimum photosensitivity, stability, and synthetic ease. They may be added at any stage in chemical finishing of the photothermographic emulsion.
Suitable sensitizing dyes such as those described in U.S. Pat. No. 3,719,495 (Lea), U.S. Pat. No. 4,396,712 (Kinoshita et al.), U.S. Pat. No. 4,439,520 (Kofron et al.), U.S. Pat. No. 4,690,883 (Kubodera et al.), U.S. Pat. No. 4,840,882 (Iwagaki et al.), U.S. Pat. No. 5,064,753 (Kohno et al.), U.S. Pat. No. 5,281,515 (Delprato et al.), U.S. Pat. No. 5,393,654 (Burrows et al), U.S. Pat. No. 5,441,866 (Miller et al.), U.S. Pat. No. 5,508,162 (Dankosh), U.S. Pat. No. 5,510,236 (Dankosh), U.S. Pat. No. 5,541,054 (Miller et al.), JP 2000-063690 (Tanaka et al.), JP 2000-112054 (Fukusaka et al.), JP 2000-273329 (Tanaka et al.), JP 2001-005145 (Arai), JP 2001-064527 (Oshiyama et al.), and JP 2001-154305 (Kita et al.), can be used in the practice of the invention. All of the publications noted above are incorporated herein by reference. A summary of generally useful spectral sensitizing dyes is contained in Research Disclosure, item 308119, Section IV, December, 1989. Additional classes of dyes useful for spectral sensitization, including sensitization at other wavelengths are described in Research Disclosure, 1994, item 36544, section V.
Teachings relating to specific combinations of spectral sensitizing dyes also include U.S. Pat. No. 4,581,329 (Sugimoto et al.), U.S. Pat. No. 4,582,786 (Ikeda et al.), U.S. Pat. No. 4,609,621 (Sugimoto et al.), U.S. Pat. No. 4,675,279 (Shuto et al.), U.S. Pat. No. 4,678,741 (Yamada et al.), U.S. Pat. No. 4,720,451 (Shuto et al.), U.S. Pat. No. 4,818,675 (Miyasaka et al.), U.S. Pat. No. 4,945,036 (Arai et al.), and U.S. Pat. No. 4,952,491 (Nishikawa et al.). All of the above publications are incorporated herein by reference.
Specific examples of useful spectral sensitizing dyes for the photothermographic materials of this invention include, for example, 2-[[5-chloro-3-(3-sulfopropyl)-2(3H)-benzothiazolylidene]methyl]-1-(3-sulfopropyl)-naphtho[1,2-d]thiazolium, inner salt, N,N-diethylethanamine salt (1:1), 2-[[5,6-dichloro-1-ethyl-1,3-dihydro-3-(3-sulfopropyl)-2H-benzimidazol-2-ylidene]methyl]-5-phenyl-3-(3-sulfopropyl)-benzoxazolium, inner salt, potassium salt, 5-chloro-2-[[5-chloro-3-(3-sulfopropyl)-2(3H)-benzothiazolylidene]methyl]-3-(3-sulfopropyl)-benzothiazolium, inner salt, N,N-diethylethanamine salt (1:1), and 5-phenyl-2-((5-phenyl-3-(3-sulfopropyl)-2(3H)-benzoxazolylidene)methyl)-3-(3-sulfopropyl)-benzothiazolium, inner salt, N,N-diethylethanamine salt(1:1).
Also useful are spectral sensitizing dyes that decolorize by the action of light or heat. Such dyes are described in U.S. Pat. No. 4,524,128 (Edwards et al.), JP 2001-109101 (Adachi), JP 2001-154305 (Kita et al.), and JP 2001-183770 (Hanyu et al.).
Spectral sensitizing dyes may be used singly or in combination. The dyes are selected for the purpose of adjusting the wavelength distribution of the spectral sensitivity, and for the purpose of supersensitization. When using a combination of dyes having a supersensitizing effect, it is possible to attain much higher sensitivity than the sum of sensitivities that can be achieved by using each dye alone. It is also possible to attain such supersensitizing action by the use of a dye having no spectral sensitizing action by itself, or a compound that does not substantially absorb visible light. Diaminostilbene compounds are often used as supersensitizers.
An appropriate amount of spectral sensitizing dye added is generally about 10xe2x88x9210 to 10xe2x88x921 mole, and preferably, about 10xe2x88x927 to 10xe2x88x922 mole per mole of silver halide.
The non-photosensitive source of reducible silver ions used in the thermographic and photothermographic materials of this invention can be any metal-organic compound that contains reducible silver (1+) ions. Such compounds are generally silver salts of silver coordinating ligands. Preferably, it is an organic silver salt that is comparatively stable to light and forms a silver image when heated to 50xc2x0 C. or higher in the presence of an exposed photocatalyst (such as silver halide, when used in a photothermographic material) and a reducing composition.
Silver salts of organic acids including silver salts of long-chain carboxylic acids are preferred. The chains typically contain 10 to 30, and preferably 15 to 28, carbon atoms. Suitable organic silver salts include silver salts of organic compounds having a carboxylic acid group. Examples thereof include a silver salt of an aliphatic carboxylic acid or a silver salt of an aromatic carboxylic acid. Preferred examples of the silver salts of aliphatic carboxylic acids include silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caprate, silver myristate, silver palmitate, silver maleate, silver fumarate, silver tartarate, silver furoate, silver linoleate, silver butyrate, silver camphorate, and mixtures thereof. Preferably, at least silver behenate is used alone or in mixtures with other silver salts.
Representative examples of useful silver salts of aromatic carboxylic acid and other carboxylic acid group-containing compounds include, but are not limited to, silver benzoate, silver substituted-benzoates (such as silver 3,5-dihydroxy-benzoate, silver o-methylbenzoate, silver m-methylbenzoate, silver p-methylbenzoate, silver 2,4-dichlorobenzoate, silver acetamidobenzoate, silver p-phenylbenzoate), silver tannate, silver phthalate, silver terephthalate, silver salicylate, silver phenylacetate, and silver pyromellitate.
Silver salts of aliphatic carboxylic acids containing a thioether group as described in U.S. Pat. No. 3,330,663 (Weyde et al.) are also useful. Soluble silver carboxylates comprising hydrocarbon chains incorporating ether or thioether linkages, or sterically hindered substitution in the xcex1-(on a hydrocarbon group) or ortho-(on an aromatic group) position, and displaying increased solubility in coating solvents and affording coatings with less light scattering can also be used. Such silver carboxylates are described in U.S. Pat. No. 5,491,059 (Whitcomb). Mixtures of any of the silver salts described herein can also be used if desired.
Silver salts of dicarboxylic acids are also useful. Such acids may be aliphatic, aromatic, or heterocyclic. Examples of such acids include, for example, phthalic acid, glutamic acid, or homo-phthalic acid.
Silver salts of sulfonates are also useful in the practice of this invention. Such materials are described for example in U.S. Pat. No. 4,504,575 (Lee). Silver salts of sulfosuccinates are also useful as described for example in EP 0 227 141 A1 (Leenders et al.).
Moreover, silver salts of acetylenes can also be used as described, for example in U.S. Pat. No. 4,761,361 (Ozaki et al.) and U.S. Pat. No. 4,775,613 (Hirai et al.).
Silver salts of compounds containing mercapto or thione groups and derivatives thereof can also be used. Preferred examples of these compounds include, but are not limited to, a heterocyclic nucleus containing 5 or 6 atoms in the ring, at least one of which is a nitrogen atom, and other atoms being carbon, oxygen, or sulfur atoms. Such heterocyclic nuclei include, but are not limited to, triazoles, oxazoles, thiazoles, thiazolines, imidazoles, diazoles, pyridines, and triazines. Representative examples of these silver salts include, but are not limited to, a silver salt of 3-mercapto-4-phenyl-1,2,4-triazole, a silver salt of 5-carboxylic-1-methyl-2-phenyl-4-thiopyridine, a silver salt of mercaptotriazine, a silver salt of 2-mercaptobenzoxazole, silver salts as described in U.S. Pat. No. 4,123,274 (Knight et al.) (for example, a silver salt of a 1,2,4-mercaptothiazole derivative, such as a silver salt of 3-amino-5-benzylthio-1,2,4-thiazole), and a silver salt of thione compounds [such as a silver salt of 3-(2-carboxyethyl)-4-methyl4-thiazoline-2-thione as described in U.S. Pat. No. 3,785,830 (Sullivan et al.)].
Examples of other useful silver salts of mercapto or thione substituted compounds that do not contain a heterocyclic nucleus include but are not limited to, a silver salt of thioglycolic acids such as a silver salt of an S-alkylthioglycolic acid (wherein the alkyl group has from 12 to 22 carbon atoms), a silver salt of a dithiocarboxylic acid such as a silver salt of a dithioacetic acid, and a silver salt of a thioamide.
In some embodiments, a silver salt of a compound containing an imino group is preferred, especially in aqueous-based imaging formulations. Preferred examples of these compounds include, but are not limited to, silver salts of benzotriazole and substituted derivatives thereof (for example, silver methylbenzotriazole and silver 5-chlorobenzotriazole), silver salts of 1,2,4-triazoles or 1-H-tetrazoles such as phenylmercaptotetrazole as described in U.S. Pat. No. 4,220,709 (deMauriac), and silver salts of imidazoles and imidazole derivatives as described in U.S. Pat. No. 4,260,677 (Winslow et al.). Particularly useful silver salts of this type are the silver salts of benzotriazole and substituted derivatives thereof. A silver salt of a benzotriazole is often used in aqueous-based thermographic and photothermographic formulations.
Organic silver salts that are particularly useful in organic solvent-based photothermographic materials include silver carboxylates (both aliphatic and aromatic carboxylates), silver triazolates, silver sulfonates, silver sulfosuccinates, and silver acetylides. Silver salts of long-chain aliphatic carboxylic acids containing 15 to 28, carbon atoms and silver salts are particularly preferred.
It is also convenient to use silver half soaps. A preferred example of a silver half soap is an equimolar blend of silver carboxylate and carboxylic acid, which analyzes for about 14.5% by weight solids of silver in the blend and which is prepared by precipitation from an aqueous solution of an ammonium or an alkali metal salt of a commercially available fatty carboxylic acid, or by addition of the free fatty acid to the silver soap. For transparent films a silver carboxylate full soap, containing not more than about 15% of free fatty carboxylic acid and analyzing for about 22% silver, can be used. For opaque thermographic and photothermographic materials, different amounts can be used.
The methods used for making silver soap emulsions are well known in the art and are disclosed in Research Disclosure, April 1983, item 22812, Research Disclosure, October 1983, item 23419, U.S. Pat. No. 3,985,565 (Gabrielsen et al.) and the references cited above.
Non-photosensitive sources of reducible silver ions can also be provided as core-shell silver salts such as those described in U.S. Pat. No. 6,355,408 (Whitcomb et al.), that is incorporated herein by reference. These silver salts include a core comprised of one or more silver salts and a shell having one or more different silver salts.
Another useful source of non-photosensitive reducible silver ions in the practice of this invention are the silver dimer compounds that comprise two different silver salts as described in copending and commonly assigned U.S. Pat. No. 6,472,131 (Whitcomb), that is incorporated herein by reference. Such non-photosensitive silver dimer compounds comprise two different silver salts, provided that when the two different silver salts comprise straight-chain, saturated hydrocarbon groups as the silver coordinating ligands, those ligands differ by at least 6 carbon atoms.
Still other useful sources of non-photosensitive reducible silver ions in the practice of this invention are the silver core-shell compounds comprising a primary core comprising one or more photosensitive silver halides, or one or more non-photosensitive inorganic metal salts or non-silver containing organic salts, and a shell at least partially covering the primary core, wherein the shell comprises one or more non-photosensitive silver salts, each of which silver salts comprises a organic silver coordinating ligand. Such compounds are described in copending and commonly assigned U.S. Ser. No. 10/208,603 (filed Jul. 30, 2002 by Bokhonov, Burleva, Whitcomb, Howlader, and Leichter), that is incorporated herein by reference.
As one skilled in the art would understand, the non-photosensitive source of reducible silver ions can include various mixtures of the various silver salt compounds described herein, in any desirable proportions.
When used in photothermographic materials, the photocatalyst and the non-photosensitive source of reducible silver ions must be in catalytic proximity (that is, reactive association). It is preferred that these reactive components be present in the same emulsion layer.
The one or more non-photosensitive sources of reducible silver ions are preferably present in an amount of about 5% by weight to about 70% by weight, and more preferably, about 10% to about 50% by weight, based on the total dry weight of the emulsion layers. Stated another way, the amount of the sources of reducible silver ions is generally present in an amount of from about 0.001 to about 0.2 mol/m2 of the dry photothermographic material, and preferably from about 0.01 to about 0.05 mol/m2 of that material.
The total amount of silver (from all silver sources) in the thermographic and photothermographic materials is generally at least 0.002 mol/m2 and preferably from about 0.01 to about 0.05 mol/m2.
When used in a photothermographic material, the reducing agent (or reducing agent composition comprising two or more components) for the source of reducible silver ions can be any material, preferably an organic material, that can reduce silver (1+) ion to metallic silver.
Conventional photographic developers can be used as reducing agents, including aromatic di- and tri-hydroxy compounds (such as hydroquinones, gallatic acid and gallic acid derivatives, catechols, and pyrogallols), aminophenols (for example, N-methylaminophenol), p-phenylenediamines, alkoxynaphthols (for example, 4-methoxy-1-naphthol), pyrazolidin-3-one type reducing agents (for example PHENIDONE(copyright)), pyrazolin-5-ones, polyhydroxy spiro-bis-indanes, indan-1,3-dione derivatives, hydroxytetrone acids, hydroxytetronimides, hydroxylamine derivatives such as for example those described in U.S. Pat. No. 4,082,901 (Laridon et al.), hydrazine derivatives, hindered phenols, amidoximes, azines, reductones (for example, ascorbic acid and ascorbic acid derivatives), leuco dyes, and other materials readily apparent to one skilled in the art.
When a silver benzotriazole silver source is used, ascorbic acid reducing agents are preferred. An xe2x80x9cascorbic acidxe2x80x9d reducing agent (also referred to as a developer or developing agent) means ascorbic acid, complexes, and derivatives thereof. Ascorbic acid developing agents are described in a considerable number of publications in photographic processes, including U.S. Pat. No. 5,236,816 (Purol et al.) and references cited therein. Useful ascorbic acid developing agents include ascorbic acid and the analogues, isomers and derivatives thereof. Such compounds include, but are not limited to, D- or L-ascorbic acid, sugar-type derivatives thereof (such as sorboascorbic acid, xcex3-lactoascorbic acid, 6-desoxy-L-ascorbic acid, L-rhamnoascorbic acid, imino-6-desoxy-L-ascorbic acid, glucoascorbic acid, fucoascorbic acid, glucoheptoascorbic acid, maltoascorbic acid, L-arabosascorbic acid), sodium ascorbate, potassium ascorbate, isoascorbic acid (or L-erythroascorbic acid), and salts thereof (such as alkali metal, ammonium or others known in the art), endiol type ascorbic acid, an enaminol type ascorbic acid, a thioenol type ascorbic acid, and an enamin-thiol type ascorbic acid, as described for example in U.S. Pat. No. 5,498,511 (Yamashita et al.), EP 0 585 792 A1 (Passarella et al.), EP 0 573 700 A1 (Lingier et al.), EP 0 588 408A1 (Hieronymus et al.), U.S. Pat. No. 5,089,819 (Knapp), U.S. Pat. No. 5,278,035 (Knapp), U.S. Pat. No. 5,384,232 (Bishop et al.), U.S. Pat. No. 5,376,510 (Parker et al.), Japanese Kokai 7-56286 (Toyoda), U.S. Pat. No. 2,688,549 (James et al.), and Research Disclosure, item 37152, March 1995. D-, L-, or D,L-ascorbic acid (and alkali metal salts thereof) or isoascorbic acid (or alkali metal salts thereof) are preferred. Mixtures of these developing agents can be used if desired.
When a silver carboxylate silver source is used in a photothermographic material, hindered phenol reducing agents are preferred. In some instances, the reducing agent composition comprises two or more components such as a hindered phenol developer and a co-developer that can be chosen from the various classes of co-developers and reducing agents described below. Ternary developer mixtures involving the further addition of contrast enhancing agents are also useful. Such contrast enhancing agents can be chosen from the various classes of reducing agents described below. Hindered phenol reducing agents are preferred (alone or in combination with one or more high-contrast co-developing agents and co-developer contrast enhancing agents).
xe2x80x9cHindered phenol reducing agentsxe2x80x9d are compounds that contain only one hydroxy group on a given phenyl ring and have at least one additional substituent located ortho to the hydroxy group. Hindered phenol reducing agents may contain more than one hydroxy group as long as each hydroxy group is located on different phenyl rings. Hindered phenol reducing agents include, for example, binaphthols (that is dihydroxybinaphthyls), biphenols (that is dihydroxybiphenyls), bis(hydroxynaphthyl)methanes, bis(hydroxyphenyl)methanes (that is bisphenols), hindered phenols, and hindered naphthols, each of which may be variously substituted.
Representative binaphthols include, but are not limited, to 1,1xe2x80x2-bi-2-naphthol, 1,1xe2x80x2-bi-4-methyl-2-naphthol and 6,6xe2x80x2-dibromo-bi-2-naphthol. For additional compounds see U.S. Pat. No. 3,094,417 (Workman) and U.S. Pat. No. 5,262,295 (Tanaka et al.), both incorporated herein by reference.
Representative biphenols include, but are not limited, to 2,2xe2x80x2-dihydroxy-3,3xe2x80x2-di-t-butyl-5,5-dimethylbiphenyl, 2,2xe2x80x2-dihydroxy-3,3xe2x80x2,5,5xe2x80x2-tetra-t-butylbiphenyl, 2,2xe2x80x2-dihydroxy-3,3xe2x80x2-di-t-butyl-5,5xe2x80x2-dichlorobiphenyl, 2-(2-hydroxy-3-t-butyl-5-methylphenyl)-4-methyl-6-n-hexylphenol, 4,4xe2x80x2-dihydroxy-3,3xe2x80x2,5,5xe2x80x2-tetra-t-butylbiphenyl and 4,4xe2x80x2-dihydroxy-3,3xe2x80x2,5,5xe2x80x2-tetra-methylbiphenyl. For additional compounds see U.S. Pat. No. 5,262,295 (noted above).
Representative bis(hydroxynaphthyl)methanes include, but are not limited to, 4,4xe2x80x2-methylenebis(2-methyl-1-naphthol). For additional compounds see U.S. Pat. No. 5,262,295 (noted above).
Representative bis(hydroxyphenyl)methanes include, but are not limited to, bis(2-hydroxy-3-t-butyl-5-methylphenyl)methane (CAO-5), 1,1xe2x80x2-bis(2-hydroxy-3,5-dimethylphenyl)-3,5,5-trimethylhexane (NONOX(copyright) or PERMANAX WSO), 1,1xe2x80x2-bis(3,5-di-t-butyl4-hydroxyphenyl)methane, 2,2xe2x80x2-bis(4-hydroxy-3-methylphenyl)propane, 4,4xe2x80x2-ethylidene-bis(2-t-butyl-6-methylphenol), 2,2xe2x80x2-isobutylidene-bis(4,6-dimethylphenol) (LOWINOX(copyright) 221B46), and 2,2xe2x80x2-bis(3,5-dimethyl-4-hydroxyphenyl)propane. For additional compounds see U.S. Pat. No. 5,262,295 (noted above).
Representative hindered phenols include, but are not limited to, 2,6-di-t-butylphenol, 2,6-di-t-butyl-4-methylphenol, 2,4-di-t-butylphenol, 2,6-dichlorophenol, 2,6-dimethylphenol and 2-t-butyl-6-methylphenol.
Representative hindered naphthols include, but are not limited to, 1-naphthol, 4-methyl-1-naphthol, 4-methoxy-1-naphthol, 4-chloro-1-naphthol and 2-methyl-1-naphthol. For additional compounds see U.S. Pat. No. 5,262,295 (noted above).
Mixtures of hindered phenol reducing agents can be used if desired.
More specific alternative reducing agents that have been disclosed in dry silver systems including amidoximes such as phenylamidoxime, 2-thienylamidoxime and p-phenoxyphenylamidoxime, azines (for example, 4-hydroxy-3,5-dimethoxybenzaldehydrazine), a combination of aliphatic carboxylic acid aryl hydrazides and ascorbic acid [such as 2,2xe2x80x2-bis(hydroxymethyl)-propionyl-xcex2-phenyl hydrazide in combination with ascorbic acid], a combination of polyhydroxybenzene and hydroxylamine, a reductone and/or a hydrazine [for example, a combination of hydroquinone and bis(ethoxyethyl)hydroxylamine], piperidinohexose reductone or formyl-4-methylphenylhydrazine, hydroxamic acids (such as phenylhydroxamic acid, p-hydroxyphenylhydroxamic acid, and o-alaninehydroxamic acid), a combination of azines and sulfonamidophenols (for example, phenothiazine and 2,6-dichloro-4-benzenesulfonamidophenol), xcex1-cyanophenylacetic acid derivatives (such as ethyl xcex1-cyano-2-methylphenylacetate and ethyl xcex1-cyanophenylacetate), bis-o-naphthols [such as 2,2xe2x80x2-dihydroxyl-1-binaphthyl, 6,6xe2x80x2-dibromo-2,2xe2x80x2-dihydroxy-1,1xe2x80x2-binaphthyl, and bis(2-hydroxy-1-naphthyl)-methane], a combination of bis-o-naphthol and a 1,3-dihydroxybenzene derivative (for example, 2,4-dihydroxybenzophenone or 2,4-dihydroxyacetophenone), 5-pyrazolones such as 3-methyl-1-phenyl-5-pyrazolone, reductones (such as dimethylaminohexose reductone, anhydrodihydro-aminohexose reductone and anhydrodihydro-piperidone-hexose reductone), sulfonamidophenol reducing agents (such as 2,6-dichloro-4-benzenesulfonamido-phenol, and p-benzenesulfonamidophenol), indane-1,3-diones (such as 2-phenylindane-1,3-dione), chromans (such as 2,2-dimethyl-7-t-butyl-6-hydroxychroman), 1,4-dihydropyridines (such as 2,6-dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine), ascorbic acid derivatives (such as 1-ascorbylpalmitate, ascorbylstearate and unsaturated aldehydes and ketones), and 3-pyrazolidones.
An additional class of reducing agents that can be used as developers are substituted hydrazines including the sulfonyl hydrazides described in U.S. Pat. No. 5,464,738 (Lynch et al.). Still other useful reducing agents are described, for example, in U.S. Pat. No. 3,074,809 (Owen), U.S. Pat. No. 3,094,417 (Workman), U.S. Pat. No. 3,080,254 (Grant, Jr.), and U.S. Pat. No. 3,887,417 (Klein et al.). Auxiliary reducing agents may be useful as described in U.S. Pat. No. 5,981,151 (Leenders et al.). All of these patents are incorporated herein by reference.
Useful co-developer reducing agents can also be used as described for example, in U.S. Pat. No. 6,387,605 (Lynch et al.), that is incorporated herein by reference. Examples of these compounds include, but are not limited to, 2,5-dioxo-cyclopentane carboxaldehydes, 5-(hydroxymethylene)-2,2-dimethyl-1,3-dioxane-4,6-diones, 5-(hydroxymethylene)-1,3-dialkylbarbituric acids, and 2-(ethoxymethylene)-1H-indene-1,3 (2H)-diones.
Additional classes of reducing agents that can be used as co-developers are trityl hydrazides and formyl phenyl hydrazides as described in U.S. Pat. No. 5,496,695 (Simpson et al.), 2-substituted malondialdehyde compounds as described in U.S. Pat. No. 5,654,130 (Murray), and 4-substituted isoxazole compounds as described in U.S. Pat. No. 5,705,324 (Murray). Additional developers are described in U.S. Pat. No. 6,100,022 (Inoue et al.). All of the patents above are incorporated herein by reference.
Yet another class of co-developers includes substituted acrylonitrile compounds that are described in U.S. Pat. No. 5,635,339 (Murray) and U.S. Pat. No. 5,545,515 (Murray et al.), both incorporated herein by reference. Examples of such compounds include, but are not limited to, the compounds identified as HET-01 and HET-02 in U.S. Pat. No. 5,635,339 (noted above) and CN-01 through CN-13 in U.S. Pat. No. 5,545,515 (noted above). Particularly useful compounds of this type are (hydroxymethylene)cyanoacetates and their metal salts.
Various contrast enhancing agents can be used in some photothermographic materials with specific co-developers. Examples of useful contrast enhancing agents include, but are not limited to, hydroxylamines (including hydroxylamine and alkyl- and aryl-substituted derivatives thereof), alkanolamines and ammonium phthalamate compounds as described for example, in U.S. Pat. No. 5,545,505 (Simpson), hydroxamic acid compounds as described for example, in U.S. Pat. No. 5,545,507 (Simpson et al.), N-acylhydrazine compounds as described for example, in U.S. Pat. No. 5,558,983 (Simpson et al.), and hydrogen atom donor compounds as described in U.S. Pat. No. 5,637,449 (Harring et al.). All of the patents above are incorporated herein by reference.
When used with a silver carboxylate silver source in a thermographic material, preferred reducing agents are aromatic di- and tri-hydroxy compounds having at least two hydroxy groups in ortho- orpara-relationship on the same aromatic nucleus. Examples are hydroquinone and substituted hydroquinones, catechols, pyrogallol, gallic acid and gallic acid esters (for example, methyl gallate, ethyl gallate, propyl gallate), and tannic acid.
Particularly preferred are reducing catechol-type reducing agents having no more than two hydroxy groups in an ortho-relationship. Preferred catechol-type reducing agents include, for example, catechol, 3-(3,4-dihydroxy-phenyl)-propionic acid, 2,3-dihydroxy-benzoic acid, 2,3-dihydroxy-benzoic acid esters, 3,4-dihydroxy-benzoic acid, and 3,4-dihydroxy-benzoic acid esters.
One particularly preferred class of catechol-type reducing agents are benzene compounds in which the benzene nucleus is substituted by no more than two hydroxy groups which are present in 2,3-position on the nucleus and have in the 1-position of the nucleus a substituent linked to the nucleus by means of a carbonyl group. Compounds of this type include 2,3-dihydroxy-benzoic acid, methyl 2,3-dihydroxy-benzoate, and ethyl 2,3-dihydroxy-benzoate.
Another particularly preferred class of catechol-type reducing agents are benzene compounds in which the benzene nucleus is substituted by no more than two hydroxy groups which are present in 3,4-position on the nucleus and have in the 1-position of the nucleus a substituent linked to the nucleus by means of a carbonyl group. Compounds of this type include, for example, 3,4-dihydroxy-benzoic acid, methyl 3,4-dihydroxy-benzoate, ethyl 3,4-dihydroxybenzoate, 3,4-dihydroxy-benzaldehyde, and phenyl-(3,4-dihydroxyphenyl)ketone. Such compounds are described, for example, in U.S. Pat. No. 5,582,953 (Uyttendaele et al.).
Still another particularly useful class of reducing agents are polyhydroxy spiro-bis-indane compounds described as photographic tanning agents in U.S. Pat. No. 3,440,049 (Moede). Examples include 3,3,3xe2x80x2,3xe2x80x2-tetramethyl-5,6,5xe2x80x2,6xe2x80x2-tetrahydroxy-1,1xe2x80x2-spiro-bis-indane (called indane I) and 3,3,3xe2x80x2,3xe2x80x2-tetramethyl-4,6,7,4xe2x80x2,6xe2x80x2,7xe2x80x2-hexahydroxy-1,1xe2x80x2-spiro-bis-indane (called indane II).
Aromatic di- and tri-hydroxy reducing agents can also be used in combination with hindered phenol reducing agents either together or in or in combination with one or more high contrast co-developing agents and co-developer contrast-enhancing agents).
The reducing agent (or mixture thereof) described herein is generally present as 1 to 10% (dry weight) of the emulsion layer. In multilayer constructions, if the reducing agent is added to a layer other than an emulsion layer, slightly higher proportions, of from about 2 to 15 weight % may be more desirable. Any co-developers may be present generally in an amount of from about 0.001% to about 1.5% (dry weight) of the emulsion layer coating.
For color imaging materials (for example, monochrome, dichrome, or full color images), one or more reducing agents can be used that can be oxidized directly or indirectly to form or release one or more dyes.
The dye-forming or releasing compound may be any colored, colorless, or lightly colored compound that can be oxidized to a colored form, or to release a preformed dye when heated, preferably to a temperature of from about 80xc2x0 C. to about 250xc2x0 C. for a duration of at least 1 second. When used with a dye- or image-receiving layer, the dye can diffuse through the imaging layers and interlayers into the image-receiving layer of the photothermographic material.
Leuco dyes or xe2x80x9cblockedxe2x80x9d leuco dyes are one class of dye-forming compounds (or xe2x80x9cblockedxe2x80x9d dye-forming compounds) that form and release a dye upon oxidation by silver ion to form a visible color image in the practice of the present invention. Leuco dyes are the reduced form of dyes that are generally colorless or very lightly colored in the visible region (optical density of less than 0.2). Thus, oxidation provides a color change that is from colorless to colored, an optical density increase of at least 0.2 units, or a substantial change in hue.
Representative classes of useful leuco dyes include, but are not limited to, chromogenic leuco dyes (such as indoaniline, indophenol, or azomethine dyes), imidazole leuco dyes such as 2-(3,5-di-t-butyl-4-hydroxyphenyl)-4,5-diphenylimidazole as described for example in U.S. Pat. No. 3,985,565 (Gabrielson et al.), dyes having an azine, diazine, oxazine, or thiazine nucleus such as those described for example in U.S. Pat. No. 4,563,415 (Brown et al.), U.S. Pat. No. 4,622,395 (Bellus et al.), U.S. Pat. No. 4,710,570 (Thien), and U.S. Pat. No. 4,782,010 (Mader et al.), and benzlidene leuco compounds as described for example in U.S. Pat. No. 4,932,792 (Grieve et al.), all incorporated herein by reference. Further details about the chromogenic leuco dyes noted above can be obtained from U.S. Pat. No. 5,491,059 (noted above, Column 13) and references noted therein.
Another useful class of leuco dyes includes what are known as xe2x80x9caldazinexe2x80x9d and xe2x80x9cketazinexe2x80x9d leuco dyes that are described for example in U.S. Pat. No. 4,587,211 (Ishida et al.) and U.S. Pat. No. 4,795,697 (Vogel et al.), both incorporated herein by reference.
Still another useful class of dye-releasing compounds includes those that release diffusible dyes upon oxidation. These are known as preformed dye release (PDR) or redox dye release (RDR) compounds. In such compounds, the reducing agents release a mobile preformed dye upon oxidation. Examples of such compounds are described in U.S. Pat. No. 4,981,775 (Swain), incorporated herein by reference.
Further, other useful image-forming compounds are those in which the mobility of a dye moiety changes as a result of an oxidation-reduction reaction with silver halide, or a nonphotosensitive silver salt at high temperature, as described for example in JP 59-165,054 (Fuji).
Still further, the reducing agent can be a compound that releases a conventional photographic dye forming color coupler or developer upon oxidation as is known in the photographic art.
The dyes that are formed or released can be the same in the same or different imaging layers. A difference of at least 60 nm in reflective maximum absorbance is preferred. More preferably, this difference is from about 80 to about 100 nm. Further details about the various dye absorbance are provided in U.S. Pat. No. 5,491,059 (noted above, Col. 14).
The total amount of one or more dye- forming or releasing compound that can be incorporated into the photothermographic materials of this invention is generally from about 0.5 to about 25 weight % of the total weight of each imaging layer in which they are located. Preferably, the amount in each imaging layer is from about 1 to about 10 weight %, based on the total dry layer weight. The useful relative proportions of the leuco dyes would be readily known to a skilled worker in the art.
The thermographic and photothermographic materials of this invention can also contain other additives such as shelf-life stabilizers, antifoggants, contrast enhancers, development accelerators, acutance dyes, post-processing stabilizers or stabilizer precursors, thermal solvents (also known as melt formers), and other image-modifying agents as would be readily apparent to one skilled in the art.
To further control the properties of photothermographic materials, (for example, contrast, Dmin, speed, or fog), it may be preferable to add one or more heteroaromatic mercapto compounds or heteroaromatic disulfide compounds of the formulae Arxe2x80x94Sxe2x80x94M1 and Arxe2x80x94Sxe2x80x94Sxe2x80x94Ar, wherein M1 represents a hydrogen atom or an alkali metal atom and Ar represents a heteroaromatic ring or fused heteroaromatic ring containing one or more of nitrogen, sulfur, oxygen, selenium, or tellurium atoms. Preferably, the heteroaromatic ring comprises benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotellurazole, imidazole, oxazole, pyrazole, triazole, thiazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline, or quinazolinone. Compounds having other heteroaromatic rings and compounds providing enhanced sensitization at other wavelengths are also envisioned to be suitable. For example, heteroaromatic mercapto compounds are described as supersensitizers for infrared photothermographic materials in EP 0 559 228B1 (Philip Jr. et al.), incorporated herein by reference.
The heteroaromatic ring may also carry substituents. Examples of preferred substituents are halo groups (such as bromo and chloro), hydroxy, amino, carboxy, alkyl groups (for example, of 1 or more carbon atoms and preferably 1 to 4 carbon atoms), and alkoxy groups (for example, of 1 or more carbon atoms and preferably of 1 to 4 carbon atoms).
Heteroaromatic mercapto compounds are most preferred. Examples of preferred heteroaromatic mercapto compounds are 2-mercaptobenzimidazole, 2-mercapto-5-methylbenzimidazole, 2-mercaptobenzothiazole and 2-mercaptobenzoxazole, and mixtures thereof.
If used, a heteroaromatic mercapto compound is generally present in an emulsion layer in an amount of at least about 0.0001 mole per mole of total silver in the emulsion layer. More preferably, the heteroaromatic mercapto compound is present within a range of about 0.001 mole to about 1.0 mole, and most preferably, about 0.005 mole to about 0.2 mole, per mole of total silver.
The photothermographic materials of the present invention can be further protected against the production of fog and can be stabilized against loss of sensitivity during storage. While not necessary for the practice of the invention, it may be advantageous to add mercury (2+) salts to the emulsion layer(s) as an antifoggant. Preferred mercury (2+) salts for this purpose are mercuric acetate and mercuric bromide. Other useful mercury salts include those described in U.S. Pat. No. 2,728,663 (Allen).
Other suitable antifoggants and stabilizers that can be used alone or in combination include thiazolium salts as described in U.S. Pat. No. 2,131,038 (Staud) and U.S. Pat. No. 2,694,716 (Allen), azaindenes as described in U.S. Pat. No. 2,886,437 (Piper), triazaindolizines as described in U.S. Pat. No. 2,444,605 (Heimbach), the urazoles described in U.S. Pat. No. 3,281,135 (Anderson), sulfocatechols as described in U.S. Pat. No. 3,235,652 (Kennard), the oximes described in GB 623,448 (Carrol et al.), polyvalent metal salts as described in U.S. Pat. No. 2,839,405 (Jones), thiuronium salts as described in U.S. Pat. No. 3,220,839 (Herz), palladium, platinum, and gold salts as described in U.S. Pat. No. 2,566,263 (Trirelli) and U.S. Pat. No. 2,597,915 (Damshroder), compounds having xe2x80x94SO2CBr3 groups as described for example in U.S. Pat. No. 5,594,143 (Kirk et al.) and U.S. Pat. No. 5,374,514 (Kirk et al.), and 2-(tribromomethylsulfonyl)quinoline compounds as described in U.S. Pat. No. 5,460,938 (Kirk et al.).
Stabilizer precursor compounds capable of releasing stabilizers upon application of heat during development can also be used. Such precursor compounds are described in for example, U.S. Pat. No. 5,158,866 (Simpson et al.), U.S. Pat. No. 5,175,081 (Krepski et al.), U.S. Pat. No. 5,298,390 (Sakizadeh et al.), and U.S. Pat. No. 5,300,420 (Kenney et al.).
In addition, certain substituted-sulfonyl derivatives of benzotriazoles (for example alkylsulfonylbenzotriazoles and arylsulfonylbenzotriazoles) have been found to be useful stabilizing compounds (such as for post-processing print stabilizing), as described in U.S. Pat. No. 6,171,767 (Kong et al.).
Furthermore, other specific useful antifoggants/stabilizers are described in more detail in U.S. Pat. No. 6,083,681 (Lynch et al.), incorporated herein by reference.
Other antifoggants are hydrobromic acid salts of heterocyclic compounds (such as pyridinium hydrobromide perbromide) as described, for example, in U.S. Pat. No. 5,028,523 (Skoug), benzoyl acid compounds as described, for example, in U.S. Pat. No. 4,784,939 (Pham), substituted propenenitrile compounds as described, for example, in U.S. Pat. No. 5,686,228 (Murray et al.), silyl blocked compounds as described, for example, in U.S. Pat. No. 5,358,843 (Sakizadeh et al.), vinyl sulfones as described, for example, in U.S. Pat. No. 6,143,487 (Philip, Jr. et al.), diisocyanate compounds as described, for example, in EP 0 600 586A1 (Philip, Jr. et al.), and tribromomethylketones as described, for example, in EP 0 600 587A1 (Oliffet al.).
Preferably, the photothermographic materials of this invention include one or more polyhalo antifoggants that include one or more polyhalo substituents including but not limited to, dichloro, dibromo, trichloro, and tribromo groups. The antifoggants can be aliphatic, alicyclic or aromatic compounds, including aromatic heterocyclic and carbocyclic compounds.
Particularly useful antifoggants are polyhalo antifoggants, such as those having a xe2x80x94SO2C(Xxe2x80x2)3 group wherein Xxe2x80x2 represents the same or different halogen atoms.
Advantageously, the photothermographic materials of this invention also include one or more thermal solvents (or melt formers). Representative examples of such compounds include, but are not limited to, salicylanilide, phthalimide, N-hydroxyphthalimide, N-potassium-phthalimide, succinimide, N-hydroxy-1,8-naphthalimide, phthalazine, 1-(2H)-phthalazinone, 2-acetylphthalazinone, benzanilide, dimethylurea, D-sorbitol, and benzenesulfonamide. Combinations of these compounds can also be used including a combination of succinimide and dimethylurea. Known thermal solvents are disclosed, for example, in U.S. Pat. No. 3,438,776 (Yudelson), U.S. Pat. No. 5,250,386 (Aono et al.), U.S. Pat. No. 5,368,979 (Freedman et al.), U.S. Pat. No. 5,716,772 (Taguchi et al.), and U.S. Pat. No. 6,013,420 (Windender).
It is often advantageous to include a base-release agent or base precursor in the photothermographic materials according to the invention to provide improved and more effective image development. A base-release agent or base precursor as employed herein is intended to include compounds which upon heating in the photothermographic material provide a more effective reaction between the described photosensitive silver halide, and the image-forming combination comprising a silver salt and the silver halide developing agent. Representative base-release agents or base precursors include guanidinium compounds, such as guanidinium trichloroacetate, and other compounds that are known to release a base but do not adversely affect photographic silver halide materials, such as phenylsulfonyl acetates. Further details are provided in U.S. Pat. No. 4,123,274 (Knight et al.).
A range of concentration of the base-release agent or base precursor is useful in the described photothermographic materials. The optimum concentration of base-release agent or base precursor will depend upon such factors as the desired image, particular components in the photothermographic material, and processing conditions.
The use of xe2x80x9ctonersxe2x80x9d or derivatives thereof that improve the image are highly desirable components of the thermographic and photothermographic materials of this invention. Toners are compounds that when added to the imaging layer shift the color of the developed silver image from yellowish-orange to brown-black or blue-black. Generally, one or more toners described herein are present in an amount of about 0.01 % by weight to about 10%, and more preferably about 0.1% by weight to about 10% by weight, based on the total dry weight of the layer in which it is included. Toners may be incorporated in the photothermographic emulsion layer or in an adjacent layer.
Such compounds are well known materials in the photothermographic art, as shown in U.S. Pat. No. 3,080,254 (Grant, Jr.), U.S. Pat. No. 3,847,612 (Winslow), U.S. Pat. No. 4,123,282 (Winslow), U.S. Pat. No. 4,082,901 (Laridon et al.), U.S. Pat. No. 3,074,809 (Owen), U.S. Pat. No. 3,446,648 (Workman), U.S. Pat. No. 3,844,797 (Willems et al.), U.S. Pat. No. 3,951,660 (Hagemann et al.), U.S. Pat. No. 5,599,647 (Defieuw et al.) and GB 1,439,478 (AGFA).
Examples of toners include, but are not limited to, phthalimide and N-hydroxyphthalimide, cyclic imides (such as succinimide), pyrazoline-5-ones, quinazolinone, 1-phenylurazole, 3-phenyl-2-pyrazoline-5-one, and 2,4-thiazolidinedione, naphthalimides (such as N-hydroxy-1,8-naphthalimide), cobalt complexes [such as hexaaminecobalt(3+) trifluoroacetate], mercaptans (such as 3-mercapto-1,2,4-triazole, 2,4-dimercaptopyrimidine, 3-mercapto-4,5-diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,4-thiadiazole), N-(aminomethyl)aryldicarboximides (such as (N,N-dimethylaminomethyl)phthalimide), and N-(dimethylaminomethyl)naphthalene-2,3-dicarboximide, a combination of blocked pyrazoles, isothiuronium derivatives, and certain photobleach agents [such as a combination of N,Nxe2x80x2-hexamethylene-bis(1-carbamoyl-3,5-dimethylpyrazole), 1,8-(3,6-diazaoctane)bis(isothiuronium)trifluoroacetate, and 2-(tribromomethylsulfonyl benzothiazole)], merocyanine dyes {such as 3-ethyl-5-[(3-ethyl-2-benzothiazolinylidene)-1-methyl-ethylidene]-2-thio-2,4-o-azolidinedione}, phthalazine and derivatives thereof [such as those described in U.S. Pat. No. 6,146,822 (Asanuma et al.)], phthalazinone and phthalazinone derivatives, or metal salts or these derivatives [such as 4-(1-naphthyl)phthalazinone, 6-chlorophthalazinone, 5,7-dimethoxyphthalazinone, and 2,3-dihydro-1,4-phthalazinedione], a combination of phthalazine (or derivative thereof) plus one or more phthalic acid derivatives (such as phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid, and tetrachlorophthalic anhydride), quinazolinediones, benzoxazine or naphthoxazine derivatives, rhodium complexes functioning not only as tone modifiers but also as sources of halide ion for silver halide formation in-situ [such as ammonium hexachlororhodate (3+), rhodium bromide, rhodium nitrate, and potassium hexachlororhodate (3+)], benzoxazine-2,4-diones (such as 1,3-benzoxazine-2,4-dione, 8-methyl-1,3-benzoxazine-2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione), pyrimidines and asym-triazines (such as 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine and azauracil) and tetraazapentalene derivatives [such as 3,6-dimercapto-1,4-diphenyl-1H,4H-2,3a,5,6a-tetraazapentalene and 1,4-di-(o-chlorophenyl)-3,6-dimercapto-1H,4H-2,3a,5,6a-tetraazapentalene].
Phthalazines and phthalazine derivatives [such as those described in U.S. Pat. No. 6,146,822 (noted above), incorporated herein by reference], phthalazinone, and phthalazinone derivatives are particularly useful toners.
Additional useful toners are substituted and unsubstituted mercaptotriazoles as described for example in U.S. Pat. No. 3,832,186 (Masuda et al.), U.S. Pat. No. 6,165,704 (Miyake et al.), U.S. Pat. No. 5,149,620 (Simpson et al.), and copending and commonly assigned U.S. Ser. No. 10/193,443 (filed Jul. 11, 2002 by Lynch, Zou, and Ulrich) and U.S. Ser. No. 10/192,944 (filed Jul. 11, 2002 by Lynch, Ulrich, and Zou), all of which are incorporated herein by reference.
The photothermographic materials of this invention can also include one or more image stabilizing compounds that are usually incorporated in a xe2x80x9cbacksidexe2x80x9d layer. Such compounds can include, but are not limited to, phthalazinone and its derivatives, pyridazine and its derivatives, benzoxazine and benzoxazine derivatives, benzothiazine dione and its derivatives, and quinazoline dione and its derivatives, particularly as described in copending and commonly assigned U.S. Ser. No. 10/041,386 (filed Jan. 8, 2002 by Kong). Other useful backside image stabilizers include, but are not limited to, anthracene compounds, coumarin compounds, benzophenone compounds, benzotriazole compounds, naphthalic acid imide compounds, pyrazoline compounds, or compounds described for example, in U.S. Pat. No. 6,465,162 (Kong et al.) and GB 1,565,043 (Fuji Photo). All of these patents and patent applications are incorporated herein by reference.
The photosensitive silver halide (when used), the non-photosensitive source of reducible silver ions, the reducing agent composition described above, and any other imaging layer additives used in the present invention are generally added to one or more binders that are either hydrophilic or hydrophobic. Thus, either aqueous or organic solvent-based formulations can be used to prepare the thermally developable materials of this invention. Mixtures of either or both types of binders can also be used. It is preferred that the binder be selected from hydrophobic polymeric materials such as, for example, natural and synthetic resins that are sufficiently polar to hold the other ingredients in solution or suspension.
Examples of typical hydrophobic binders include, but are not limited to, polyvinyl acetals, polyvinyl chloride, polyvinyl acetate, cellulose acetate, cellulose acetate butyrate, polyolefins, polyesters, polystyrenes, polyacrylonitrile, polycarbonates, methacrylate copolymers, maleic anhydride ester copolymers, butadiene-styrene copolymers, and other materials readily apparent to one skilled in the art. Copolymers (including terpolymers) are also included in the definition of polymers. The polyvinyl acetals (such as polyvinyl butyral and polyvinyl formal) and vinyl copolymers (such as polyvinyl acetate and polyvinyl chloride) are particularly preferred. Particularly suitable binders are polyvinyl butyral resins that are available as BUTVAR(copyright) B79 and PIOLOFORM(copyright) BS-18 or PIOLOFORM(copyright) BL-16. Aqueous dispersions (or latexes) of hydrophobic binders may also be used.
Examples of useful hydrophilic binders include, but are not limited to, proteins and protein derivatives, gelatin and gelatin-like derivatives (hardened or unhardened, including alkali- and acid-treated gelatins, acetylated gelatin, oxidized gelatin, phthalated gelatin, and deionized gelatin), cellulosic materials such as hydroxymethyl cellulose and cellulosic esters, acrylamide/methacrylamide polymers, acrylic/methacrylic polymers polyvinyl pyrrolidones, polyvinyl alcohols, poly(vinyl lactams), polymers of sulfoalkyl acrylate or methacrylates, hydrolyzed polyvinyl acetates, polyacrylamides, polysaccharides (such as dextrans and starch ethers), and other synthetic or naturally occurring vehicles commonly known for use in aqueous-based photographic emulsions (see for example, Research Disclosure, item 38957, noted above). Cationic starches can be used as a peptizer for tabular silver halide grains as described in U.S. Pat. No. 5,620,840 (Maskasky) and U.S. Pat. No. 5,667,955 (Maskasky).
Hardeners for various binders may be present if desired. Useful hardeners are well known and include diisocyanate compounds as described for example, in EP 0 600 586 B1 (Philip, Jr. et al.) and vinyl sulfone compounds as described in U.S. Pat. No. 6,143,487 (Philip, Jr. et al.), and EP 0 640 589 (Gathmann et al.), aldehydes and various other hardeners as described in U.S. Pat. No. 6,190,822 (Dickerson et al.). The hydrophilic binders used in the photothermographic materials are generally partially or fully hardened using any conventional hardener. Useful hardeners are well known and are described, for example, in T. H. James, The Theory of the Photographic Process, Fourth Edition, Eastman Kodak Company, Rochester, N.Y., 1977, Chapter 2, pp. 77-8.
Where the proportions and activities of the thermographic and photothermographic materials require a particular developing time and temperature, the binder(s) should be able to withstand those conditions. When a hydrophobic binder is used, it is preferred that the binder does not decompose or lose its structural integrity at 120xc2x0 C. for 60 seconds. When a hydrophilic binder is used, it is preferred that the binder does not decompose or lose its structural integrity at 150xc2x0 C. for 60 seconds. It is more preferred that it does not decompose or lose its structural integrity at 177xc2x0 C. for 60 seconds.
The polymer binder(s) is used in an amount sufficient to carry the components dispersed therein. The effective range of amount of polymer can be appropriately determined by one skilled in the art. Preferably, a binder is used at a level of about 10% by weight to about 90% by weight, and more preferably at a level of about 20% by weight to about 70% by weight, based on the total dry weight of the layer in which it is included.
It is particularly useful in the thermally developable materials of this invention to use predominantly (more than 50% by weight of total binder weight) hydrophobic binders in both imaging and non-imaging layers on the side of the support having the imaging layer(s).
The thermally developable materials of this invention comprise a polymeric support that is preferably a flexible, transparent film that has any desired thickness and is composed of one or more polymeric materials, depending upon their use. The supports are generally transparent (especially if the material is used as a photomask) or at least translucent, but in some instances, opaque supports may be useful. They are required to exhibit dimensional stability during thermal development and to have suitable adhesive properties with overlying layers. Useful polymeric materials for making such supports include, but are not limited to, polyesters (such as polyethylene terephthalate and polyethylene naphthalate), cellulose acetate and other cellulose esters, polyvinyl acetal, polyolefins (such as polyethylene and polypropylene), polycarbonates, and polystyrenes (and polymers of styrene derivatives). Preferred supports are composed of polymers having good heat stability, such as polyesters and polycarbonates. Polyethylene terephthalate film is a particularly preferred support. Various support materials are described, for example, in Research Disclosure, 1979, item 18431. A method of making dimensionally stable polyester films is described in Research Disclosure, 1999, item 42536.
It is also useful to use supports comprising dichroic mirror layers wherein the dichroic mirror layer reflects radiation at least having the predetermined range of wavelengths to the emulsion layer and transmits radiation having wavelengths outside the predetermined range of wavelengths. Such dichroic supports are described in U.S. Pat. No. 5,795,708 (Boutet), incorporated herein by reference.
It is further useful to use transparent, multilayer, polymeric supports comprising numerous alternating layers of at least two different polymeric materials. Such multilayer polymeric supports preferably reflect at least 50% of actinic radiation in the range of wavelengths to which the photothermographic sensitive material is sensitive, and provide photothermographic materials having increased speed. Such transparent, multilayer, polymeric supports are described in WO 02/21208 (Simpson et al.), incorporated herein by reference.
Opaque supports can also be used, such as dyed polymeric films and resin-coated papers that are stable to high temperatures.
Support materials can contain various colorants, pigments, antihalation or acutance dyes if desired. For example, the support can contain conventional blue dyes that differ in absorbance from colorants in the various frontside or backside layers, for example as described in U.S. Pat. No. 6,248,442 (Van Achere et al.). Support materials may be treated using conventional procedures (such as corona discharge) to improve adhesion of overlying layers, or subbing or other adhesion-promoting layers can be used. Useful subbing layer formulations include those conventionally used for photographic materials such as vinylidene halide polymers.
Support materials may also be treated or annealed to reduce shrinkage and promote dimensional stability.
An organic-based formulation for the thermographic and photothermographic emulsion layer(s) can be prepared by dissolving and dispersing the binder, the photocatalyst (when used), the source of non-photosensitive silver ions, the reducing composition, toner(s), and optional addenda in an organic solvent, such as toluene, 2-butanone (methyl ethyl ketone), acetone, or tetrahydrofuran.
Alternatively, the desired imaging components can be formulated with a hydrophilic binder (such as gelatin, a gelatin-derivative, or a latex) in water or water-organic solvent mixtures to provide aqueous-based coating formulations.
Thermographic and photothermographic materials of the invention can contain plasticizers and lubricants such as poly(alcohols) and diols of the type described in U.S. Pat. No. 2,960,404 (Milton et al.), fatty acids or esters such as those described in U.S. Pat. No. 2,588,765 (Robijns) and U.S. Pat. No. 3,121,060 (Duane), and silicone resins such as those described in GB 955,061 (DuPont). The materials can also contain matting agents such as starch, titanium dioxide, zinc oxide, silica, and polymeric beads including beads of the type described in U.S. Pat. No. 2,992,101 (Jelley et al.) and U.S. Pat. No. 2,701,245 (Lynn). Polymeric fluorinated surfactants may also be useful in one or more layers of the imaging materials for various purposes, such as improving coatability and optical density uniformity as described in U.S. Pat. No. 5,468,603 (Kub).
U.S. Pat. No. 6,436,616 (Geisler et al.) describes various means of modifying photothermographic materials to reduce what is known as the xe2x80x9cwoodgrainxe2x80x9d effect, or uneven optical density. This effect can be reduced or eliminated by several means, including treatment of the support, adding matting agents to the topcoat, using acutance dyes in certain layers or other procedures described in the noted publication.
The thermographic and photothermographic materials of this invention can be constructed of one or more layers on the imaging side of the support. Single layer materials should contain the photocatalyst, the non-photosensitive source of reducible silver ions, the reducing agent composition, the binder, as well as optional materials such as toners, acutance dyes, coating aids, and other adjuvants.
Two-layer constructions comprising a single imaging layer coating containing all the ingredients and a surface protective topcoat are generally found on the frontside of the materials of this invention. However, two-layer constructions containing photocatalyst and non-photosensitive source of reducible silver ions in one imaging layer (usually the layer adjacent to the support) and the reducing composition and other ingredients in the second imaging layer or distributed between both layers are also envisioned.
Layers to promote adhesion of one layer to another in thermographic and photothermographic materials are also known, as described for example in U.S. Pat. No. 5,891,610 (Bauer et al.), U.S. Pat. No. 5,804,365 (Bauer et al.), and U.S. Pat. No. 4,741,992 (Przezdziecki). Adhesion can also be promoted using specific polymeric adhesive materials as described for example in U.S. Pat. No. 5,928,857 (Geisler et al.).
Layers to reduce emissions from the film may also be present, including the polymeric barrier layers described in U.S. Pat. No. 6,352,819 (Kenney et al.), U.S. Pat. No. 6,352,820 (Bauer et al.), and U.S. Pat. No. 6,420,102B1 (Bauer et al.), all incorporated herein by reference.
Thermographic and photothermographic formulations described herein can be coated by various coating procedures including wire wound rod coating, dip coating, air knife coating, curtain coating, slide coating, or extrusion coating using hoppers of the type described in U.S. Pat. No. 2,681,294 (Beguin). Layers can be coated one at a time, or two or more layers can be coated simultaneously by the procedures described in U.S. Pat. No. 2,761,791 (Russell), U.S. Pat. No. 4,001,024 (Dittman et al.), U.S. Pat. No. 4,569,863 (Keopke et al.), U.S. Pat. No. 5,340,613 (Hanzalik et al.), U.S. Pat. No. 5,405,740 (LaBelle), U.S. Pat. No. 5,415,993 (Hanzalik et al.), U.S. Pat. No. 5,525,376 (Leonard), U.S. Pat. No. 5,733,608 (Kessel et al.), U.S. Pat. No. 5,849,363 (Yapel et al.), U.S. Pat. No. 5,843,530 (Jerry et al.), U.S. Pat. No. 5,861,195 (Bhave et al.), and GB 837,095 (Ilford). A typical coating gap for the emulsion layer can be from about 10 to about 750 xcexcm, and the layer can be dried in forced air at a temperature of from about 20xc2x0 C. to about 100xc2x0 C. It is preferred that the thickness of the layer be selected to provide maximum image densities greater than about 0.2, and more preferably, from about 0.5 to 5.0 or more, as measured by a MacBeth Color Densitometer Model TD 504.
When the layers are coated simultaneously using various coating techniques, a xe2x80x9ccarrierxe2x80x9d layer formulation comprising a single-phase mixture of the two or more polymers described above may be used. Such formulations are described in U.S. Pat. No. 6,355,405 (Ludemann et al.), incorporated herein by reference.
Mottle and other surface anomalies can be reduced in the materials of this invention by incorporation of a fluorinated polymer as described for example in U.S. Pat. No. 5,532,121 (Yonkoski et al.) or by using particular drying techniques as described, for example in U.S. Pat. No. 5,621,983 (Ludemann et al.).
Preferably, two or more layers are simultaneously applied to a film support using slide coating. The first and second fluids used to coat these layers can be the same or different solvents (or solvent mixtures).
While the first and second layers can be coated on one side of the film support, manufacturing methods can also include forming on the opposing or backside of said polymeric support, one or more additional layers, including the required conductive layer, and optionally an antihalation layer or a layer containing a matting agent (such as silica), or a combination of such layers.
It is also contemplated that the photothermographic materials of this invention can include emulsion layers on both sides of the support. Such constructions can further include at least one infrared radiation absorbing heat-bleachable compositions as an antihalation underlayer beneath at least one emulsion layer.
To promote image sharpness, photothermographic materials according to the present invention can contain one or more layers containing acutance and/or antihalation dyes. These dyes are chosen to have absorption close to the exposure wavelength and are designed to absorb scattered light. One or more antihalation compositions may be incorporated into one or more antihalation layers according to known techniques, as an antihalation backing layer, as an antihalation underlayer, or as an antihalation overcoat. Additionally, one or more antihalation or acutance dyes may be incorporated into one or more frontside layers such as the photothermographic emulsion layer, carrier layer, primer layer, underlayer, or topcoat layer according to known techniques. It is preferred that the photothermographic materials of this invention contain an antihalation composition on the backside of the support, and more preferably in the backside topcoat layer.
Dyes useful as antihalation and acutance dyes include squaraine dyes described in U.S. Pat. No. 5,380,635 (Gomez et al.), U.S. Pat. No. 6,063,560 (Suzuki et al.), and EP 1 083 459A1 (Kimura), the indolenine dyes described in EP 0 342 810A1 (Leichter), and the cyanine dyes described in copending and commonly assigned U.S. Ser. No. 10/01 1,892 (filed Dec. 5, 2001 by Hunt, Kong, Ramsden, and LaBelle). All of the above references are incorporated herein by reference.
It is also useful in the present invention to employ compositions including acutance or antihalation dyes that will decolorize or bleach with heat during processing. Dyes and constructions employing these types of dyes are described in, for example, U.S. Pat. No. 5,135,842 (Kitchin et al.), U.S. Pat. No. 5,266,452 (Kitchin et al.), U.S. Pat. No. 5,314,795 (Helland et al.), U.S. Pat. No. 6,306,566, (Sakurada et al.), U.S. Published Application 2001-0001704 (Sakurada et al.), JP Kokai 2001-142175 (Hanyu et al.), and JP Kokai 2001-183770 (Hanye et al.). Also useful are bleaching compositions described in JP Kokai 11-302550 (Fujiwara), JP Kokai 2001-109101 (Adachi), JP Kokai 2001-51371 (Yabuki et al.), and JP Kokai 2000-029168 (Noro). All of the above publications are incorporated herein by reference.
Particularly useful heat-bleachable backside antihalation compositions can include an infrared radiation absorbing compound such as an oxonol dyes and various other compounds used in combination with a hexaarylbiimidazole (also known as a xe2x80x9cHABIxe2x80x9d), or mixtures thereof. Such HABI compounds are well known in the art, such as U.S. Pat. No. 4,196,002 (Levinson et al.), U.S. Pat. No. 5,652,091 (Perry et al.), and U.S. Pat. No. 5,672,562 (Perry et al.), all incorporated herein by reference. Examples of such heat-bleachable compositions are described for example in U.S. Pat. No. 6,455,210 (Irving et al.), U.S. Ser. No. 09/875,772 (filed Jun. 6, 2001 by Goswami, Ramsden, Zielinski, Baird, Weinstein, Helber, and Lynch), and U.S. Ser. No. 09/944,573 (filed Aug. 31, 2001 by Ramsden and Baird), all incorporated herein by reference.
Under practical conditions of use, the compositions are heated to provide bleaching at a temperature of at least 90xc2x0 C. for at least 0.5 seconds. Preferably, bleaching is carried out at a temperature of from about 1 00xc2x0 C. to about 200xc2x0 C. for from about 5 to about 20 seconds. Most preferred bleaching is carried out within 20 seconds at a temperature of from about 110xc2x0 C. to about 130xc2x0 C.
In some embodiments, the photothermographic materials of this invention comprise one or more acutance dyes in the one or more thermally developable imaging layers. In some embodiments the photothermographic materials comprise one or more antihalation dyes in the one or more non-imaging layers on the imaging side of the support. In some embodiments, the photothermographic materials of this invention comprise one or more antihalation dyes in the backside layer on the support, and more preferably in the backside topcoat layer. Such non-imaging layers include, for example, carrier layers, primer layers, barrier layers, or topcoat layers.
Some materials of the present invention may have an optical density at a wavelength close to that of the exposure of from about 0.2 to about 3 on the imaging side of the support, and an optical density of up to 2 on the backside of the support, as measured using a conventional spectrophotometer.
In preferred embodiments, the thermally developable materials of this invention include a surface protective layer on the same side of the support as the one or more thermally-developable layers and a conductive layer on the back side of the support underneath a protective layer that can also include an antihalation composition.
The essential feature of the present invention is the presence of at least one conductive layer on the backside (non-imaging side) of the support that includes one or more specific non-acicular metal antimonate particles having a composition represented by the following Structure I or II:
M+2Sb+52O6xe2x80x83xe2x80x83(I)
wherein M is zinc, nickel, magnesium, iron, copper, manganese, or cobalt,
Ma+3Sb+5O4xe2x80x83xe2x80x83(II)
wherein Ma is indium, aluminum, scandium, chromium, iron, or gallium.
Thus, these particles are generally metal oxides that are doped with antimony.
Preferably, the non-acicular metal antimonate particles are composed of ZnSb2O6. Several conductive metal antimonates are commercially available from Nissan Chemical America Corporation including the preferred ZnSb2O6 non-acicular particles that are available as a 40% (solids) organosol dispersion under the tradename CELNAX(copyright) CX-Z401M.
Alternatively, the metal antimonate particles can be prepared using methods described for example in U.S. Pat. No. 5,457,013 (noted above) and references cited therein.
The metal antimonate particles in the backside conductive layer are predominately (more than 40% by weight of total particles) in the form of non-acicular particles as opposed to xe2x80x9cacicularxe2x80x9d particles. By xe2x80x9cnon-acicularxe2x80x9d particles is meant not needlelike, that is, not acicular. Thus, the shape of the metal antimonate particles can be granular, spherical, ovoid, cubic, rhombic, tabular, tetrahedral, octahedral, icosahedral, truncated cubic, truncated rhombic, or any other non-needle like shape.
Generally, these metal particles have an average diameter of from about 15 to about 20 nm as measured across the largest particle dimension using the BET method.
The non-acicular metal antimonate particles generally comprise from about 40 to about 55% (preferably from about 40 to about 50%) by weight of the buried backside conductive layer. Another way of defining the amount of particles is that they are generally present in the backside conductive layer in an amount of from about 0.05 to about 2 g/m2. Mixtures of different types of non-acicular metal antimonate particles can be used if desired.
The non-acicular metal antimonate particles are also generally present in an amount sufficient to provide a backside surface resistivity measured at 70xc2x0 F. (21.1xc2x0 C.) and 20% relative humidity of 4xc3x971012 ohms/sq or less, a static decay time of 0.02 seconds, or a wet electrode resistivity of 1xc3x971012 ohms/sq or less and preferably 1xc3x971010 ohms/sq or less as measured using the techniques and procedures described herein.
An essential aspect of the present invention is the fact that the conductive metal antimonate particles are present in one or more backside conductive layers that are xe2x80x9cburiedxe2x80x9d on the backside of the support, meaning that there is at least one other layer disposed over the backside conductive layer(s). Moreover, the relationship of the backside conductive layer(s), and the layer or layers immediately adjacent is important because the types of polymers and binders in these layers are designed to provide excellent adhesion to one another as well as acceptably dispersing the conductive metal antimonate particles and/or or layer components, and are readily coated simultaneously or separately.
The xe2x80x9cburiedxe2x80x9d backside conductive layer may also be relatively thin in comparison to other layers on the backside, and in such instances, it can have a dry thickness of less than 2 xcexcm, and preferably a dry thickness of from about 0.06 to about 2 xcexcm. Because of these useful features, the xe2x80x9cburiedxe2x80x9d backside conductive layer is useful as a xe2x80x9ccarrierxe2x80x9d layer. The term xe2x80x9ccarrier layerxe2x80x9d is often used when multiple layers are coated using slide coating and the buried backside conductive layer is a thin layer adjacent to the support.
In one preferred embodiment, the backside conductive layer is directly disposed on the support without the use of primer or subbing layers, or other adhesion-promoting means such as support surface treatments. Thus, the support can be used in an xe2x80x9cuntreatedxe2x80x9d and xe2x80x9cuncoatedxe2x80x9d form when a buried backside conductive layer is used.
The layer directly disposed over the conductive layers is known herein as a xe2x80x9cfirstxe2x80x9d layer and can be known as a xe2x80x9cprotectivexe2x80x9d layer that can be the outermost topcoat layer or have further layer(s) disposed thereon. This first layer comprises a film-forming polymer. The backside conductive layer immediately underneath comprises the non-acicular metal antimonate particles in a mixture of two or more polymers that includes a xe2x80x9cfirstxe2x80x9d polymer serving to promote adhesion of the backside conductive layer directly to the polymeric support, and a xe2x80x9csecondxe2x80x9d polymer that is different than and forms a single phase mixture with the first polymer.
It is preferred that film-forming polymer of the first layer and the second polymer of the backside conductive layer are the same or different polyvinyl acetal resins, polyester resins, cellulosic polymers, maleic anhydrideester copolymers, or vinyl polymers. It is more preferred that the film-forming polymer of the first layer and the second polymer of the backside conductive layer is a polyvinyl acetal such as polyvinyl butyral or cellulose ester such as cellulose acetate butyrate. It is preferred that the xe2x80x9cfirstxe2x80x9d polymer of the backside conductive layer is a polyester resin. It is most preferred that the backside conductive layer use a single phase mixture of a polyester resin as a xe2x80x9cfirstxe2x80x9d polymer and cellulose acetate butyrate as a xe2x80x9csecondxe2x80x9d polymer.xe2x80x9d
It is preferred to use a mixture of polymers, that is, a first polymer that promotes adhesion to the support and a second polymer that promotes adhesion to the first layer. For example, when the support is a polyester film, and the backside conductive layer contains a polyvinyl acetal or a cellulose ester, then a preferred mixture of polymers in that conductive layer is a single phase mixture of a polyester resin and a polyvinyl acetal such as polyvinyl butyral or cellulose ester such as cellulose acetate butyrate.
In another embodiment, the buried backside conductive layer is disposed between a xe2x80x9cfirstxe2x80x9d layer and a xe2x80x9csecondxe2x80x9d layer directly adhering the support. In this embodiment, the xe2x80x9cfirstxe2x80x9d layer is directly above the backside conductive layer and is known herein as a xe2x80x9cfirstxe2x80x9d layer, a xe2x80x9cprotectivexe2x80x9d layer, or a xe2x80x9cprotective topcoatxe2x80x9d layer. It can be the outermost topcoat layer or have further layer(s) disposed thereon. This first layer comprises a film-forming polymer. The conductive layer immediately beneath the first layer comprises the non-acicular metal antimonate particles in a polymer that serves to promote adhesion of the backside conductive layer to the first layer as well as to a xe2x80x9csecondxe2x80x9d layer immediately beneath it. This second layer is directly adhered to the polymeric support. The second layer directly adhered to the support comprises a mixture of two or more polymers. The first polymer serves to promote adhesion of the second layer directly to the polymeric support. The second polymer serves to promote adhesion of the second layer to the backside conductive layer.
It is preferred that the film-forming polymer of the first layer, the polymer of the backside conductive layer, and the second polymer of the second layer are the same or different polyvinyl acetal resins, polyester resins, cellulosic ester polymers, maleic anhydride-ester copolymers, or vinyl polymers. A preferred polymer is cellulose acetate butyrate.
It is preferred that the second, adhesion-promoting, layer use a single phase mixture of a polyester resin as a xe2x80x9cfirstxe2x80x9d polymer and a polyvinyl acetal such as polyvinyl butyral or cellulose ester such as cellulose acetate butyrate as a xe2x80x9csecondxe2x80x9d polymer.xe2x80x9d
In another embodiment, the buried backside conductive layer is disposed between a xe2x80x9cfirstxe2x80x9d layer and a xe2x80x9csecondxe2x80x9d layer directly adhering to the support. In this embodiment, the first layer is directly above the backside conductive layer is known herein as a xe2x80x9cfirstxe2x80x9d layer, a xe2x80x9cprotectivexe2x80x9d layer, or a xe2x80x9cprotective topcoatxe2x80x9d layer. It can be the outermost topcoat layer or have further layer(s) disposed thereon. This first layer comprises a film-forming polymer. The conductive layer immediately beneath the first layer comprises the non-acicular metal antimonate particles in a mixture of two or more polymers, a xe2x80x9cfirstxe2x80x9d polymer that serves to promote adhesion of the conductive layer to the second layer, and a xe2x80x9csecondxe2x80x9d polymer that serves to promote adhesion of the conductive layer to the first layer.
It is preferred that the film-forming polymer of the first layer, and the xe2x80x9csecondxe2x80x9d polymer of the backside conductive layer are the same or different polyvinyl acetal resins, polyester resins, cellulosic ester polymers, maleic anhydride-ester copolymers, or vinyl polymers. A preferred polymer is cellulose acetate butyrate.
It is preferred that the polymer of second, adhesion-promoting, layer and the xe2x80x9cfirstxe2x80x9d polymer of the backside conductive layer are the same or different polyester resins.
Representative xe2x80x9cfirstxe2x80x9d polymers can be chosen from one or more of the following classes: polyvinyl acetals (such as polyvinyl butyral, polyvinyl acetal, and polyvinyl formal), cellulosic ester polymers (such as cellulose acetate, cellulose diacetate, cellulose triacetate, cellulose acetate propionate, hydroxymethyl cellulose, cellulose nitrate, and cellulose acetate butyrate), polyesters, polycarbonates, epoxies, rosin polymers, polyketone resin, vinyl polymers (such as polyvinyl chloride, polyvinyl acetate, polystyrene, polyacrylonitrile, and butadiene-styrene copolymers), acrylate and methacrylate polymers, and maleic anhydride ester copolymers. The polyvinyl acetals, polyesters, cellulosic ester polymers, and vinyl polymers such as polyvinyl acetate and polyvinyl chloride are particularly preferred, and the polyvinyl acetals, polyesters, and cellulosic ester polymers are more preferred. Polyester resins are most preferred. Thus, the adhesion-promoting polymers are generally hydrophobic in nature.
Representative xe2x80x9csecondxe2x80x9d polymers include polyvinyl acetals, cellulosic polymers, vinyl polymers (as defined above for the xe2x80x9cfirstxe2x80x9d polymer), acrylate and methacrylate polymers, and maleic anhydride-ester copolymers. The most preferred xe2x80x9csecondxe2x80x9d polymers are polyvinyl acetals and cellulosic ester polymers (such as cellulose acetate, cellulose diacetate, cellulose triacetate, cellulose acetate propionate, hydroxymethyl cellulose, cellulose nitrate, and cellulose acetate butyrate). Cellulose acetate butyrate is a particularly preferred second polymer. Of course, mixtures of these second polymers can be used in the backside conductive layer. These second polymers are also soluble or dispersible in the organic solvents described above.
It is preferred that the xe2x80x9cfirstxe2x80x9d and xe2x80x9csecondxe2x80x9d polymers are compatible with each other or are of the same polymer class. One skilled in the art would readily understand from the teaching herein which polymers are xe2x80x9ccompatible withxe2x80x9d or xe2x80x9cof the same classxe2x80x9d as those film-forming polymers. For example, it is most preferred to use a single phase mixture of a polyester resin as a xe2x80x9cfirstxe2x80x9d polymer and a cellulose ester such as cellulose acetate butyrate as a xe2x80x9csecondxe2x80x9d polymer.xe2x80x9dMany of the film-forming polymers useful in the first layer are described in other places herein (for example, binders used in imaging layers and or other conventional backside layers).
The backside conductive layers are generally coated out of one or more miscible organic solvents including, but not limited to, methyl ethyl ketone (2-butanone, MEK), acetone, toluene, tetrahydrofuran, ethyl acetate, ethanol, methanol, or any mixture of any two or more of these solvents.
The backside conductive layers described herein can be coated by various coating procedures such as those described above for the thermographic and photothermographic imaging layers. Such procedures include wire wound rod coating, dip coating, air knife coating, curtain coating, slide coating, roll coating, reverse roll coating, gravure coating, or extrusion coating
The weight ratio of xe2x80x9cfirstxe2x80x9d polymer to xe2x80x9csecondxe2x80x9d polymer in the backside conductive layer is generally from about 10:90 to about 40:60 , and preferably from about 10:90 to about 30:70. A most preferred polymer combination is of polyester and cellulose acetate butyrate having a weight ratio of about 20:80.
The backside conductive layer can also include still other polymers that are not defined herein as first or second polymers. These additional polymers can be either hydrophobic or hydrophilic. Some hydrophilic polymers that may be present include, but are not limited to, proteins or polypeptides such as gelatin and gelatin derivatives, polysaccharides, gum arabic, dextrans, polyacrylamides (including polymethacrylamides), polyvinyl pyrrolidones and others that would be readily apparent to one skilled in the art.
The polymers in the backside conductive layer generally comprise at least 0.1 weight % (preferably at least 0.2 weight %) of the total wet coating weight of the layer. The maximum amount of such polymers is generally 40 weight %, and preferably up to 20 weight %, based on total wet coating weight.
As noted above, in preferred embodiments, the backside conductive layer is a relatively thin xe2x80x9cburiedxe2x80x9d layer that provides desired benefits (that is, sensitometric and physical properties) beyond the necessary conductivity. Typically, the backside conductive layer has a dry thickness up to 2 xcexcm and preferably up to 1 xcexcm. The minimum dry thickness is generally at least 0.06 xcexcm and preferably at least 0.15 xcexcm. More preferably, the dry thickness is between 0.15 xcexcm and0.50xcexcm.
Other components of the backside conductive layer include materials that may improve coatability or adhesion, crosslinking agents (such as diisocyanates), surfactants and shelf-aging promoters.
The backside conductive layer may also include other addenda commonly added to such formulations including, but not limited to, shelf life extenders, antihalation dyes, colorants to control tint and tone, UV absorbing materials, to improve light-box stability, and coating aids such as surfactants to achieve high quality coatings, all in conventional amounts. It is also useful to add inorganic matting agents such as the polysilicic acid particles as described in U.S. Pat. No. 4,828,971 (Przezdziecki), poly(methyl methacrylate) beads as described in U.S. Pat. No. 5,310,640 (Markin et al.), or polymeric cores surrounded by a layer of colloidal inorganic particles as described in U.S. Pat. No. 5,750,328 (Melpolder et al.).
In one preferred embodiment, the xe2x80x9cfirstxe2x80x9d backside layer (usually referred to as a protective or topcoat layer) includes an antihalation composition, such as those antihalation compositions described above.
The thermally developable materials of this invention can also include one or more antistatic or conductive layers on the frontside of the support. Such layers may contain metal antimonates as described above, or other conventional antistatic agents known in the art for this purpose such as soluble salts (for example, chlorides or nitrates), evaporated metal layers, or ionic polymers such as those described in U.S. Pat. No. 2,861,056 (Minsk) and U.S. Pat. No. 3,206,312 (Sterman et al.), or insoluble inorganic salts such as those described in U.S. Pat. No. 3,428,451 (Trevoy), electroconductive underlayers such as those described in U.S. Pat. No. 5,310,640 (Markin et al.), electronically-conductive metal antimonate particles such as those described above and in U.S. Pat. No. 5,368,995 (Christian et al.), electrically-conductive metal-containing particles dispersed in a polymeric binder such as those described in EP 0 678 776A1 (Melpolder et al.), and fluorochemicals that are described in numerous publications.
When particles are added to a coating layer, streaking can become a problem. Streaks can be caused by particles getting caught on the lips of a coating slot, causing flow instability, disturbing coating flow, and resulting in streaks. Streaks can also be formed by a denser liquid from an upper coating slot displacing a less dense liquid from a lower coating slot or even by flowing into an incompletely filled lower coating slot. In very thin layers formed from low-viscosity liquids, such as those used as carrier layers in slide coating, flow rates, and coating slot heights need to be adjusted carefully to prevent such penetration (see, for example, E. B. Gutoff and E. D. Cohen xe2x80x9cCoating and Drying Defects,xe2x80x9d John Wiley and Sons, New York, 1995, p. 135).
The addition of metal antimonate particles to carrier layers used in slide coating procedures has been found to reduce streaking. The size of the metal antimonate particles appears to be too small to cause the flow instabilities seen with the larger particles normally used in coating. Moreover, the addition of metal antimonate particles to the carrier layer increases the density of the carrier layer without increasing its viscosity or otherwise reducing its usefulness as a carrier layer. Penetration of the denser upper layer into the coating slot of the lower layer is reduced or prevented by this increase in density. Penetration is most reduced when sufficient metal antimonate particles are present to increases the density of the lower layer so that it is equal to or greater then the density of the solution coated above it.
The thermally developable materials of the present invention can be imaged in any suitable manner consistent with the type of material using any suitable imaging source (typically some type of radiation or electronic signal for photothermographic materials and a source of thermal energy for thermographic materials). In some embodiments, the materials are sensitive to radiation in the range of from about at least 300 nm to about 1400 nm, and preferably from about 300 nm to about 850 nm. In other embodiments, the materials are sensitive to radiation at 700 nm or greater (such as from about 750 to about 950 nm).
Imaging can be achieved by exposing the photothermographic materials of this invention to a suitable source of radiation to which they are sensitive, including ultraviolet radiation, visible light, near infrared radiation and infrared radiation to provide a latent image. Suitable exposure means are well known and include sources of radiation, including: incandescent or fluorescent lamps, xenon flash lamps, lasers, laser diodes, light emitting diodes, infrared lasers, infrared laser diodes, infrared light-emitting diodes, infrared lamps, or any other ultraviolet, visible, or infrared radiation source readily apparent to one skilled in the art, and others described in the art, such as in Research Disclosure, September, 1996, item 38957. Particularly useful infrared exposure means include laser diodes, including laser diodes that are modulated to increase imaging efficiency using what is known as multi-longitudinal exposure techniques as described in U.S. Pat. No. 5,780,207 (Mohapatra et al.). Other exposure techniques are described in U.S. Pat. No. 5,493,327 (McCallum et al.).
Thermal development conditions will vary, depending on the construction used but will typically involve heating the imagewise exposed material at a suitably elevated temperature. Thus, the latent image can be developed by heating the exposed material at a moderately elevated temperature of, for example, from about 50xc2x0 C. to about 250xc2x0 C. (preferably from about 80xc2x0 C. to about 200xc2x0 C. and more preferably from about 100xc2x0 C. to about 200xc2x0 C.) for a sufficient period of time, generally from about 1 to about 120 seconds. Heating can be accomplished using any suitable heating means such as a hot plate, a steam iron, a hot roller or a heating bath.
In some methods, the development is carried out in two steps. Thermal development takes place at a higher temperature for a shorter time (for example at about 150xc2x0 C. for up to 10 seconds), followed by thermal diffusion at a lower temperature (for example at about 80xc2x0 C.) in the presence of a transfer solvent.
When imaging thermographic materials of this invention, the image may be xe2x80x9cwrittenxe2x80x9d simultaneously with development at a suitable temperature using a thermal stylus, a thermal print head or a laser, or by heating while in contact with a heat-absorbing material. The thermographic materials may include a dye (such as an IR-absorbing dye) to facilitate direct development by exposure to laser radiation. The dye converts absorbed radiation to heat.
The thermographic and photothermographic materials of the present invention are sufficiently transmissive in the range of from about 350 to about 450 nm in non-imaged areas to allow their use in a method where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation sensitive imageable medium. For example, imaging the materials and subsequent development affords a visible image. The heat-developed thermographic and photothermographic materials absorbs ultraviolet or short wavelength visible radiation in the areas where there is a visible image and transmit ultraviolet or short wavelength visible radiation where there is no visible image. The heat-developed materials may then be used as a mask and positioned between a source of imaging radiation (such as an ultraviolet or short wavelength visible radiation energy source) and an imageable material that is sensitive to such imaging radiation, such as a photopolymer, diazo material, photoresist, or photosensitive printing plate. Exposing the imageable material to the imaging radiation through the visible image in the exposed and heat-developed photothermographic material provides an image in the imageable material. This method is particularly useful where the imageable medium comprises a printing plate and the photothermographic material serves as an imagesetting film.
The present invention also provides a method for the formation of a visible image (usually a black-and-white image) by first exposing to electromagnetic radiation and thereafter heating the inventive photothermographic material. In one embodiment, the present invention provides a method comprising:
a) imagewise exposing the photothermographic material of this invention to electromagnetic radiation to which the photocatalyst (for example, a photosensitive silver halide) of the material is sensitive, to form a latent image, and
b) simultaneously or sequentially, heating the exposed material to develop the latent image into a visible image.
The photothermographic material may be exposed in step A using any source of radiation, to which it is sensitive, including ultraviolet radiation, visible light, infrared radiation or any other infrared radiation source readily apparent to one skilled in the art.
The present invention also provides a method for the formation of a visible image (usually a black-and-white image) by thermal imaging of the inventive thermographic material. In one embodiment, the present invention provides a method comprising:
A) thermal imaging of the thermographic material of this invention to form a visible image.
This visible image prepared from either a thermographic or photothermographic material can also be used as a mask for exposure of other photosensitive imageable materials, such as graphic arts films, proofing films, printing plates and circuit board films, that are sensitive to suitable imaging radiation (for example, UV radiation). This can be done by imaging an imageable material (such as a photopolymer, a diazo material, a photoresist, or a photosensitive printing plate) through the heat-developed thermographic or photothermographic material. Thus, in some other embodiments wherein the thermographic or photothermographic material comprises a transparent support, the image-forming method further comprises:
c) positioning the exposed and heat-developed thermographic or photothermographic material between a source of imaging radiation and an imageable material that is sensitive to the imaging radiation, and
d) exposing the imageable material to the imaging radiation through the visible image in the exposed and heat-developed photothermographic material to provide an image in the imageable material.
The following examples are provided to illustrate the practice of the present invention and the invention is not meant to be limited thereby.
All materials used in the following examples are readily available from standard commercial sources, such as Aldrich Chemical Co. (Milwaukee Wis.) unless otherwise specified. All percentages are by weight unless otherwise indicated. The following additional terms and materials were used.
ACRYLOID(copyright) A-21 is an acrylic copolymer available from Rohm and Haas (Philadelphia, Pa.).
ALBACAR 5970 is a 1.9 xcexcm precipitated calcium carbonate. It is available from Specialty Minerals, Inc. (Bethlehem, Pa.).
BUTVAR(copyright) B-79 is a polyvinyl butyral resin available from Solutia, Inc. (St. Louis, Mo.).
CAB 171-15S and CAB 381-20 are cellulose acetate butyrate resins available from Eastman Chemical Co. (Kingsport, Tenn.).
CELNAX(copyright) CX-Z401M is a 40% organosol dispersion of non-acicular zinc antimonate particles in methanol. It was obtained from Nissan Chemical America Corporation (Houston, Tex.).
L-9342 is a perfluorinated organic antistatic agent described as Compound 1 of U.S. Pat. No. 4,975,363 (Cavallo et al.). It was obtained from 3M Company (St. Paul, Minn.).
MEK is methyl ethyl ketone (or 2-butanone).
PERMANAX WSO (or NONOX(copyright)) is 1,1-bis(2-hydroxy-3,5-dimethylphenyl)-3,5,5-trimethylhexane [CAS RN=7292-14-0] and is available from St-Jean PhotoChemicals, Inc. (Quebec, Canada).
PIOLOFORM(copyright) BL-16 and PIOLOFORM(copyright) BN-18 are polyvinyl butyral resins available from Wacker Polymer Systems (Adrian, Mich.).
SYLOID(copyright) 74X6000 is a synthetic amorphous silica that is available from Grace-Davison (Columbia, Md.).
VITEL(copyright) PE-2700B LMW is a polyester resin available from Bostik, Inc. (Middleton, Mass.).
Backcoat Dye BC-1 is cyclobutenediylium, 1,3-bis[2,3-dihydro-2,2-bis[[1-oxohexyl)oxy]methyl]-1H-perimidin-4-yl]-2,4-dihydroxy-, bis(inner salt). It is believed to have the structure shown below.
Ethyl-2-cyano-3-oxobutanoate has the structure shown below.
Vinyl Sulfone-1 (VS-1) is described in U.S. Pat. No. 6,143,487 and has the following structure:
Resistivity Measurements:
Resistivity of antistatic coatings was measured using three different methods, the xe2x80x9cdecay timexe2x80x9d test, the xe2x80x9csurface resistivityxe2x80x9d test, and the xe2x80x9cwet electrode resistivityxe2x80x9d test.
In the decay xe2x80x9ctime test,xe2x80x9d an ETS Model 406D Static Decay Meter (Electro-Tech Systems Inc., Glenside, Pa.) was used to determine the rate of static charge decay on a sample. The sample is subjected to a fixed voltage to induce an electrostatic charge on its surface. The charge is then dissipated (bled off) by providing a path for current flow to ground. The time for the charge to dissipate to certain pre-selected levels (10% in our test) is recorded.
Decay times were measured in a room maintained at 70xc2x0 F. (21.1xc2x0 C.) and 20% relative humidity (RH) unless otherwise specified. All testing was done in this room after samples had been acclimated for 18 to 24 hours. A +5 kV charge was applied and the time to reach 10% of the charge (90% decay) was recorded. Samples that demonstrate poor antistatic properties do not dissipate charge and their decay times are reported as xe2x80x9cnot conductive.xe2x80x9dIn order to function as an antistatic material, a compound should provide a coating having a decay time of less than 25 seconds and preferably less than 5 seconds at a temperature of 70xc2x0 F. (21.1xc2x0 C.) and a relative humidity of 20%. Decay times less than 1 second are preferred.
In the xe2x80x9csurface resistivityxe2x80x9d (SER) test, three Keithley instruments, a Model 247 High Voltage Supply, a Model 480 Digital Picometer, and a Model 6105 Resistivity Adapter (Keithley Instruments Inc., Cleveland Ohio) were used.
Surface resistivity was again measured in a room maintained at 70xc2x0 F. (21.1xc2x0 C.)/20% relative humidity (RH) and all testing was done in this room. A potential of 500 volts was applied to the sample and the current going through the sample was measured. The conversion from amperes (current) to ohm/sq (resistivity) was calculated using the following equation (provided by Kiethley):
Ohm/sq=26,700/amperes
The Kiethley Device cannot measure current below 1xc3x9710xe2x88x9212 amperes. Thus resistivity greater than 2.67xc3x971016 ohm/sq cannot be calculated. Films having a resistivity calculated greater than 2.67xc3x971016 ohm/sq are reported below as greater than 2.67xc3x971016 ohm/sq. In order to function as an antistatic material, a compound should provide a coating having a resistivity of less than 1xc3x971014 ohm/sq, preferably less than 1xc3x971012 ohm/sq, and more preferably less than 1011 ohm/sq at a temperature of 70xc2x0 F. (21.1xc2x0 C.) and a relative humidity of 20%.
In the xe2x80x9cwet electrode resistivityxe2x80x9d (WER) test, antistatic performance was evaluated by measuring the internal resistivity of the overcoated electrically-conductive antistatic layer using a salt bridge wet electrode resistivity measurement technique. This technique is described in R. A. Elder xe2x80x9cResistivity Measurements on Buried Conductive Layers,xe2x80x9d EOS/ESD Symposium Proceedings, Lake Buena Vista, Fla., 1990, pp. 251-254, incorporated herein by reference. [EOS/ESD stands for Electrical Overstress/Electrostatic Discharge]. Typically, antistatic layers with WER values greater than about 1xc3x971012 ohm/square are considered to be ineffective at providing static protection for photographic imaging elements. We have also found WER measurements to be more predictive of how an antistatic material will perform when used in a commercial product.
Sensitometry Measurements:
Densitometry measurements were made on a custom built computer-scanned densitometer and meeting ISO Standards 5-2 and 5-3 and are believed to be comparable to measurements from commercially available densitometers. Dmin is the density of the non-exposed areas after development and it is the average of the eight lowest density values. | {
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The instant invention relates generally to clothes dryer exhaust vents and more specifically it relates to a vent bag for a clothes dryer which provides an air filter for catching lint coming out of the vent pipe of the clothes dryer.
There are available various conventional clothes dryers which do not provide the novel improvements of the invention herein disclosed. | {
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1. Field of the Invention
The present invention relates to magnetic recording and assisted magnetic recording, and particularly to a magnetic recording medium capable of realizing an areal recording density of at least 150 gigabits per square centimeter and a method of manufacturing the same.
2. Background Art
Hard disk drives (HDDs) are indispensable devices for usage requiring large-capacity information recording in computers and consumer-electronics products. In the future too, needs for large-capacity recording will be high. It is required to increase the areal recording densities of recording media in order to realize large capacity while serving the needs for savings in space and energy. Presently, approaches to high density by improvement in perpendicular magnetic recording have been attempted. However, according to conventional perpendicular magnetic recording, it is estimated that a feasible maximum areal recording density is 150 Gbit/cm2 (1 Tbit/inch2). The reason why the areal recording density has the limit is interpreted to be due to a fundamental principle of recording according to which a medium suitable for high density recording deteriorates in thermal stability. High density magnetic recording requires magnetic grains forming a magnetic recording medium to be finer to form highly accurate recording bit boundaries (magnetic transition region). However, in a case of making the magnetic grains fine, the magnetic energy KuV that stabilizes magnetization directions of respective grains cannot retain a magnitude sufficient against thermal energy kBT as a disturbance. Accordingly, a phenomenon occurs that recorded magnetization information deteriorates (thermal decay of magnetization) immediately after recording. Here, Ku, V, kB, and T are a uniaxial magnetic anisotropy energy, a magnetic grain volume, the Boltzmann constant, and the absolute temperature, respectively.
Improvement in areal recording density while maintaining thermal stability requires use of a magnetic recording layer having a high magnetic anisotropy energy Ku. As described in IEEE Trans. Magn., vol. 36, p. 10 (2000) and the like, an L10 FePt ordered alloy is a material having perpendicular magnetic anisotropy energy Ku higher than that of existing CoCrPt alloys, and receives attention as a next-generation magnetic recording layer. Use of the L10 FePt ordered alloy as a magnetic recording layer absolutely necessitates reduction in exchange interaction between crystalline grains. Accordingly, in recent years, many attempts of adding a non-magnetic material, such as MgO, SiO2 or C, to an L10 FePt ordered alloy to form granular structure have been reported. Here, the granular structure represents a structure including magnetic crystalline grains made of an FePt alloy and grain boundaries made of surrounding non-magnetic material.
However, recording cannot be made on the magnetic recording layer material having such a high Ku, using an existing magnetic head. This is because a soft magnetic material used for a magnetic writer pole has the maximum value of saturated magnetic flux density B of approximately 2.5 T, and thus the magnitude of the magnetic field generated by the magnetic writer pole is limited. Thus, assisted magnetic recording, or a new concept of magnetic recording, has been proposed. Presently, two assisting schemes, laser heating and microwave irradiation schemes have mainly been proposed, and referred to as thermally assisted magnetic recording (IEEE Trans. Magn., vol. 37, p. 1234 (2001)) and microwave assisted magnetic recording (IEEE Trans. Magn., vol. 44, p. 125 (2008)), respectively. These assisted magnetic recording schemes irradiate a magnetic recording layer with assist energy to facilitate magnetization reversal and then form a recording bit using a magnetic field generated by the magnetic writer pole.
Since FePt has a disordered fcc structure as a metastable phase in addition to the L10 ordered structure, this requires to be subjected to an ordering process by heat treatment. It has been known that, the higher the degree of ordering (degree of ordering S), the higher the magnetic anisotropy energy is obtained. Improvement in degree of ordering requires heat treatment. The methods therefor are broadly divided into a method of heating after forming a film of an FePt alloy (post annealing method), and a method of forming a film of an FePt alloy on a preheated substrate (substrate heating method). In a case of granulation by adding a nonmetal element to an FePt alloy thin film, a fabrication method is required to be determined on the basis of any of heating methods as a premise.
An example of a fabrication method using the post annealing method is disclosed in Appl. Phys. Lett., vol. 91, p. 072502 (2007). According to this document, a post annealing process is applied to a multilayer film structure in which a periodic structure including an Fe layer, Pt layer, and a SiO2 layer as a grain boundary material is repeatedly stacked n times, thereby obtaining L10 FePt alloy magnetic thin film having a granular structure. The diameters of the FePt magnetic grains at this time are approximately 6 nm. Accordingly, the grains can be applied to high density magnetic recording. On the other hand, an example of the fabrication method using the substrate heating method is disclosed in Appl. Phys. Lett., vol. 91, p. 132506 (2007) and J. Appl. Phys., vol. 103, p. 023910 (2008). These documents have reported that a granular structure can be obtained without using the periodically laminated structure such as in Appl. Phys. Lett., vol. 91, p. 072502 (2007), and the diameters of the grains can relatively easily be controlled according to a heating temperature of a substrate and an amount of addition of non-magnetic material. Various oxides and carbon have been discussed as a grain boundary material. It has been understood that C is a specific grain boundary material which can realize an excellent granular structure among these materials. J. Magn. Magn. Mater., vol. 322, p. 2658 (2010) discloses an example of fabricating an L10 FePt alloy magnetic thin film which realizes both a favorable granular structure with the diameters of magnetic grains of about 6 nm and a high coercivity Hc of at least 3 T (30 kOe). | {
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This application is a U.S. National Phase Application under 35 USC 371 of International Application PCT/DE99/01870 (not published in English) filed Jun. 23, 1999.
The invention relates to a process for production of monocrystalline powders and a monogram membrane comprising the same.
A monogram membrane is a thin film constructed from one layer of powder. The powder grains are bonded together.
From the article entitled xe2x80x9cMonograin layersxe2x80x9d by T. S. Velde and G. W. M. T. van Helden in Philips Technical Review, 29 (1968), 238-242, it is known that a monogram membrane can be produced from monocrystalline CdS powder. Monocrystalline powder comprising CdS is obtained by crushing a relatively large single crystal. A bonding agent is then applied as a thin film on a glass substrate. The powder is scattered on the film of the bonding agent. Thereupon a layer of the powder adheres to the bonding agent. The other powder grains not attached to the bonding agent are eliminated. Dissolved resin, polymer or components for the same are added to the powder grains adhering to the bonding agent. After the solution has been dried and cured, the film containing a powder layer is peeled from the substrate. If necessary, the powder grains can be exposed by etching, starting from the surface. Otherwise the powder grains are or remain held together by the resin, etc. and thus form the desired monogram membrane.
One problem is the production of the monocrystalline powder. For example, it is relatively expensive first of all to produce a relatively large single crystal. It is also hardly possible to produce powder grains of uniform size by mechanical crushing.
Powder grains of uniform size are necessary in order to obtain a monogram membrane of uniform thickness.
A monogram membrane can be used advantageously in the art of photovoltaics, among others. Copper indium diselenide is a particularly suitable material for this purpose.
The object of the invention is to provide an inexpensive process for production of monocrystalline powder with predetermined grain sizes. A further object of the invention is to provide, for the first time, particular monogram membranes comprising powders formed according to the process.
The objects are achieved by a process having the features described hereinbelow as well as by a monogram membrane having the features described hereinbelow. Advantageous embodiments are specified hereinbelow.
The present invention concerns a process for producing a monocrystalline powder comprising a semiconductor material. The process comprises:
(a) fusing together individual components of the semiconductor material or salts thereof to form a melt;
(b) adding a fluxing agent to the melt;
(c) adjusting the temperature of the melt together with the fluxing agent such that the components or salts thereof melt and at the same time the powder to be produced crystallizes out, so that monocrystalline powder grains grow; and
(d) cooling the melt such that the growth of the monocrystalline powder grains is stopped.
The present invention also relates to a monogram membrane comprising monocrystalline copper indium diselenide or GaAs grains produced according to the above-described process.
According to the process, a melt is formed and a fluxing agent is added. The melt is formed from the individual components of a semiconductor material, preferably a II/VI or III/V semiconductor, an example of which can therefore be the components of copper indium diselenide or GaAs. Salts containing the components can also be fused instead of the components. The components or their salts are preferably chosen such that the components are present in the melt in the same stoichiometric composition as that of the powder to be produced.
The melt must then be brought to a temperature at which the individual components or their salts become fused and at the same time the powder to be produced crystallizes out. Such a temperature typically lies between 300xc2x0 C. and 1000xc2x0 C. In the appropriate temperature range, monocrystalline powder grains are formed in the melt. Once the powder grains have reached the desired size, the melt is cooled or quenched so rapidly that the growth of the powder grains is stopped as a result. The appropriate instant of quenching, as well as the appropriate temperature profile for obtaining desired powder sizes are determined by, for example, preliminary experiments. After quenching or cooling it is expedient to eliminate the fluxing agent.
The process is simple and inexpensive, since it is not necessary to produce large single crystals beforehand. The grains grow uniformly, and so the resulting powder comprises grains of uniform size.
To produce copper indium diselenide monocrystalline powder, the salt melt can be formed from CuSe and In, or from Cu, Se and In, or from Cuxe2x80x94In alloys and Se, or from Cu, In or Se salts with appropriate melting points. A typical melt then has the composition of, for example, 6.35 g Cu, 11.5 g In, 15.8 g Se and 40 vol % CuSe.
NaCl or an excess of Se or selenides can be used as a fluxing agent in a melt containing copper indium diselenide. The proportion of fluxing agent typically amounts to 40 vol % of the melt. In general, however, it can range between 10 vol % and 90 vol %. The melt together with the fluxing agent is introduced into, for example, a quartz ampoule. The quartz ampoule is evacuated and fused. Thereafter the quartz ampoule together with the contents cited as an example is heated to at least 300xc2x0 C., especially 600xc2x0 C. As soon as the components have melted, monocrystalline copper indium diselenide grains begin to grow. The growth of a semiconductor such as copper indium diselenide takes place as a function of time and of the fluxing agent used. Depending on fluxing agent and desired size of the powder grains, a treatment time ranging from 5 minutes to 100 hours is necessary.
In order to stop the growth selectively, the melt is cooled. The cooling rate determines the fault content and fault type in the material, as well as the surface morphology. Quenching can be completed within a few seconds. The melt can also be cooled over a period of several hours. For this purpose the quartz ampoule together with the contents can be cooled in a water bath or in air at an instant determined by preliminary experiments. Thereafter the contents are removed from the quartz ampoule and the fluxing agent is eliminated. In the case of NaCl, this can be achieved, for example, by dissolving the NaCl in water, provided the powder grains are insoluble in water, as is the case of copper indium diselenide. If Se is used as the fluxing agent, it can be eliminated by volatilization of Se.
The temperature range in which recrystallization takes place depends on the fluxing agent and the desired grain size, and can lie between 100xc2x0 C. and 1000xc2x0 C. The process has been used to produce, among other substances, monocrystalline copper indium diselenide powder with extremely high electrical conductivity. Grain diameters of 40 xcexcm, for example, have been obtained. Grains with resistance of 10 to 30xcexa9 have been achieved. These values correspond to specific electrical resistivities of 0.1 to 0.6 xcexa9m.
It was possible to produce powders with diameters of 0.1 xcexcm to 0.1 mm.
From the powders produced according to the process, there can be produced by the prior art described hereinabove in the background of the invention monogram membranes which can be used, for example, in photovoltaics. A minimum diameter of 10 xcexcm was necessary for production of monogram membranes, since otherwise a continuous polymer film was not possible. A diameter of 50 xcexcm should not be exceeded for the production of monogram membranes, since otherwise, in the art of photovoltaics, for example, undesirably high series resistances develop and material is wasted. It is worth emphasizing that the grain sizes produced according to the process vary only slightly within a batch. | {
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Mobility, being capable of moving from place to place or of moving quickly from one state to another, has been one of the ultimate goals of humanity throughout recorded history. The automobile has likely done more in helping individuals achieve that goal than any other development. Since its inception, societies around the globe have experienced rates of change in their manner of living that are directly related to the percentage of motor vehicle owners among the population.
Prior art automobiles and light trucks include a body, the function of which is to contain and protect passengers and their belongings. Bodies are connected to the numerous mechanical, electrical, and structural components that, in combination with a body, comprise a fully functional vehicle. The nature of the prior art connections between a vehicle body and vehicular componentry may result in certain inefficiencies in the design, manufacture, and use of vehicles. Three characteristics of prior art body connections that significantly contribute to these inefficiencies are the quantity of connections; the mechanical nature of many of the connections; and the locations of the connections on the body and on the componentry.
In the prior art, the connections between a body and componentry are numerous. Each connection involves at least one assembly step when a vehicle is assembled; it is therefore desirable to reduce the number of connections to increase assembly efficiency. The connections between a prior art body and prior art vehicular componentry include multiple load-bearing connectors to physically fasten the body to the other components, such as bolts and brackets; electrical connectors to transmit electrical energy to the body from electricity-generating components and to transmit data from sensors that monitor the status of the componentry; mechanical control linkages, such as the steering column, throttle cable, and transmission selector; and ductwork and hoses to convey fluids such as heated and cooled air from an HVAC unit to the body for the comfort of passengers.
Many of the connections in the prior art, particularly those connections that transmit control signals, are mechanical linkages. For example, to control the direction of the vehicle, a driver sends control signals to the steering system via a steering column. Mechanical linkages result in inefficiencies, in part, because different driver locations in different vehicles require different mechanical linkage dimensions and packaging. Thus, new or different bodies often cannot use “off-the-shelf” components and linkages. Componentry for one vehicle body configuration is typically not compatible for use with other vehicle body configurations. Furthermore, if a manufacturer changes the design of a body, a change in the design of the mechanical linkage and the component to which it is attached may be required. The change in design of the linkages and components requires modifications to the tooling that produces the linkages and components.
The location of the connections on prior art vehicle bodies and componentry also results in inefficiencies. In prior art body-on-frame architecture, connection locations on the body are often not exposed to an exterior face of the body, and are distant from corresponding connections on the componentry; therefore, long connectors such as wiring harnesses and cables must be routed throughout the body from componentry. The vehicle body of a fully-assembled prior art vehicle is intertwined with the componentry and the connection devices, rendering separation of the body from its componentry difficult and labor-intensive, if not impossible. The use of long connectors increases the number of assembly steps required to attach a vehicle to its componentry.
Furthermore, prior art vehicles typically have internal combustion engines that have a height that is a significant proportion of the overall vehicle height. Prior art vehicle bodies are therefore designed with an engine compartment that occupies about a third of the front (or sometimes the rear) of the body length. Compatibility between an engine and a vehicle body requires that the engine fit within the body's engine compartment without physical part interference. Moreover, compatibility between a prior art chassis with an internal combustion engine and a vehicle body requires that the body have an engine compartment located such that physical part interference is avoided. For example, a vehicle body with an engine compartment in the rear is not compatible with a chassis with an engine in the front. | {
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In the formation of silver halide emulsions suitable for use in photographic materials, it is necessary to sensitize the emulsions. Chemical sensitization is utilized to improve the photo efficiency of the emulsions. Spectral sensitization is utilized to make grains sensitive to specific wavelengths of light. The addition of chemical and spectral sensitizing materials to silver halide grains normally is referred to as finishing of the grains. During finishing, other additives are also introduced into the emulsions, such as antifoggants, coating aids, ripeners, supersensitizers, and surfactants.
The application of heat during emulsion finishing has a tendency to raise the minimum fog level of unexposed areas. Fog also may increase in an emulsion during storage. Therefore, the use of antifoggants is necessary to minimize these effects. Such antifoggants are discussed in Research Disclosure 36544 of September 1994 in Section VII.
The antifoggants generally are added during the finishing process after chemical sensitization and prior to, during, or after the spectral sensitization. There is a continuing need for improvements in the efficiency of antifoggants.
It is known in the formation of high chloride grains (above 90%) to utilize bromide as a material added during finishing. It is added to the grain surface in order to improve the adsorption of sensitizing dyes onto the grain surface, enhance the speed/fog performance of the grains, and also improve reciprocity. Generally this material is added as a sodium or potassium bromide salt. It is also known that bromide may be added to the emulsion by the addition of a Lippmann (fine grain) emulsion to the finish. Such a process is illustrated in U.S. Pat. No. 4,865,962. Other photographic materials may be with a fine grain emulsion as shown in Konica JP 02-103,032 (1990).
Generally modern negative-working color photographic paper utilizes high chloride emulsions. Such emulsions, while allowing rapid development and high quality images, are subject to fog upon storage.
Problem to be Solved by the Invention
There is a continuing need for improvements in Dmin of negative-working photographic papers by decreasing the fog. Particularly, there is a need to prevent the increase of fog during storage of such papers prior to use. There is also a need to more efficiently use known antifoggants. | {
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Visual impairment is generally understood as vision loss to such a degree as to be considered a signification limitation of visual capability. A visually-impaired individual may be “partially sighted,” “with low vision,” “legally blind,” or “totally blind,” depending upon the degree of visual impairment. Also, depending upon the degree of visual impairment, a visually-impaired individual may require additional support or tools to perform the activities of daily life.
For example, a visually-impaired individual may utilize tactile or auditory feedback tools to assist in the performing of activities of daily life. Such tools may include speech-synthesis systems and systems using braille displays. These and other tools have enabled the visually-impaired to more effectively use mainstream computer applications. The availability of assistive technology for the visually-impaired has been increasing, and there have been increasing efforts to further develop assistive technologies that enable the visually-impaired to more effectively access information available on computer systems. | {
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Several United States patents have issued to the applicant for drying coal in a fluidized bed reactor. These include U.S. Pat. No. 5,830,246 (“Process for processing coal”), U.S. Pat. No. 5,830,247(“Process for processing coal”), U.S. Pat. No. 5,858,035 (“Process for processing coal”), U.S. Pat. No. 5,904,741 (“Process for processing coal”), and U.S. Pat. No. 6,162,265 (“Process for processing coal”). The entire disclosure of each of these United States patents is hereby incorporated by reference into this specification.
With increasing energy demands, and increasing energy production costs, there is a need for efficient production methods for upgrading low rank or “wet” coal products to consumable energy products. Many researchers have devoted significant resources to developing these processes and technologies.
The coal industry has faced excessive transportation costs for these moisture-laden low-rank coal products. However, while drying coal to a low moisture content prior to shipment offers significant advantages in terms of reduced transportation costs, it renders the coal subject to spontaneous combustion during shipment and storage. Significant inflagration and explosion hazards are created, exposing workers and emergency responders to dangerous conditions.
The problem of spontaneous combustion of coal has been well known for more than half a century. Sub-bituminous, bituminous, lignite, brown coal and coal char can spontaneously combust by chemical reactions between the coal, moisture and oxygen present in the air. This reaction can occur when water combining with other components in the coal generate a sufficient amount of heat to raise the temperature of the coal to the ignition point. Additionally, noncarbonaceous or unsaturated carbon compound materials present in the coal may oxidize upon exposure to air, which in turn generates a sufficient amount of heat for the coal to reach ignition temperature.
U.S. Pat. No. 4,170,456 (Inhibiting spontaneous combustion of coal char) explains that, “Spontaneous combustion occurs when the rate of heat generation from oxidation exceeds the rate of heat dissipation. Previous workers have found that the reason spontaneous combustion does not occur more often than it does is that the oxidation rate of coal char decreases with the increasing time of or extent of oxidation. Therefore, when coal char is exposed to oxygen, a race begins between the effects of high temperature coefficient of oxidation rate and the decreasing rate of oxidation as oxygen is consumed by the coal char. Depending on the winner, spontaneous combustion occurs or doesn't occur.” The entire disclosure of each of these United States patents is hereby incorporated by reference into this specification.
Commonly used drying processes utilize a hot combustion gas to drive moisture from the coal in a bed of coal, a fluidized bed, a kiln or a rotary device. Conventional drying methods often center around pyrolysis and result in a coal product which is active and subject to self-heating by the processes described above.
U.S. Pat. No. 6,146,432 (Pressure gradient passivation of carbonaceous material normally susceptible to spontaneous combustion) explains “Low-rank coals, such as sub-bituminous coal or lignite may contain more than about 10% moisture and typically 15-50 weight percent moisture. Some low-rank coals may contain as much as 60 weight percent moisture. Such wet low-rank coals cannot be shipped economically over great distances due to the cost of transporting a significant fraction of unusable material in the form of water. Further, these low-rank coals cannot be burned efficiently due to the energy required to vaporize the water. Due to the lowered heating value and high cost of shipping unusable material, it is advantageous to remove all or part of the water from the low-rank coals prior to shipment and/or storage. However, drying such fuels usually leads to activation of the low-rank coals or chars. The reactive coals or chars may be hazardous due to the potential for damage to property or life due to the reaction of the coal or char with atmospheric oxygen and moisture and consequential heating of the coal, which makes it subject to spontaneous ignition during either shipment or storage. Indicators of the propensity of coals or chars to spontaneously combust include the uptake of oxygen as measured in terms of torr of oxygen per gram of material. Methods for testing this indicator are listed in U.S. Bureau of Mines “Report of Investigation 9330” by Miron, Smith, and Lazzara. The terms “oxygen uptake” and “oxygen demand” refer to the test methods of the “Report of Investigation 9330” or related test methods when used in this document. In the past, wet low-rank coals such as those from the western United States have been dried by methods such as, but not limited to, thermal drying using process heat, waste heat, microwaves, pressurized water, steam, hot oil, molten metals, and other supplies of high temperatures. The heated coals release the free moisture trapped in the pores, water molecules associated with hydrated molecules or associated in other ways with the coal, producing dried coals or chars. Other methods of drying may include mechanical drying (such as centrifugal separation), the use of dry gases, or the use of desiccants or absorbents. Once dried, coals or chars can become more active and are known to spontaneously combust.” The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
Many researches have devoted significant resources to address this problem, some of which will be briefly described. None of the approaches, and in particular, those utilizing an oxygenated environment, have realized commercial success.
To reduce the potential for the spontaneous combustion of coal, approaches have focused on filming or coating the surface of the coal with deactivating fluids to seal it using oils, polymers, tars, waxes or other hydrocarbon materials. Reference is made, e.g., to U.S. Pat. No. 1,960,917 (Process for treating coal), U.S. Pat. No. 2,197,792 (Coal spraying chute), U.S. Pat. No. 2,204,781 (Art of protecting coal and like), U.S. Pat. No. 2,610,115 (Method for dehydrating lignite) and U.S. Pat. No. 2,811,427 (Lignite fuel). U.S. Pat. No. 3,961,914 (Process for treating coal to make it resistant to spontaneous combustion) disclosed a silicon dioxide film on the coal surface. The entire disclosure of each of these United States patents is hereby incorporated by reference into this specification. Without wishing to be bound by any particular theory, applicants believe that favorable altering of the surface components reduces the reactivity and oxidation.
Other methods have used application of oxidizing agents or treatment with high temperature under pressure (U.S. Pat. No. 6,146,432 at column 2, lines 35-60). The entire disclosure of each of these United States patents is hereby incorporated by reference into this specification. Yet other processes use controlled drying in a manner that particle surface pores are self-sealed by hydrocarbon material evolved from the particles.
Other approaches include the prolonged exposure of the coal to air, the use of oxidizing agents sprayed on coal, and treating the coal with high-temperature water under pressure. The coatings perform their work by covering the pores and limiting the access of active components of the air to active sites on the dried coal. U.S. Pat. No. 3,723,079 (Stabilization of coal) explains: “For example, coal piles are often arranged in a particular manner to obtain safe storage; e.g., thin layers which are compacted with sloping sides at a maximum angle of 14°, smooth final surfaces, and top surface continually smoothed as coal is removed from the top only. Other approaches to prevent spontaneous combustion during storage involves chemical treatment of the coal, e.g., coating the coal with petroleum products and their emulsions, spraying with calcium bicarbonate or aqueous hydroquinone or amines. Such treatments, however, are either not completely effective or are excessively expensive for a low prices commodity such as coal.” The entire disclosure of such United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 3,985,516 (Coal drying and passivation process) and U.S. Pat. No. 3,985,517 (Coal passivation process) disclose mixing of coal in a fluidized bed with at least 0.5 weight percent of hydrocarbon material during the heating process. These coatings are effective in preventing reabsorption of moisture, however, such coatings are expensive due to the cost of the added hydrocarbon materials. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 1,632,829 (Method of drying coal and the like) describes a process for drying wet coal by steam heating it. In the method described, steam disposed above the coal is maintained at high partial pressure to prevent escape of the moisture while the coal temperature elevates. Thereafter, the steam pressure is reduced, permitting the escape of moisture and rapid drying of the coal. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 4,052,169 (Treatment of solid fuels) describes a process for upgrading lignitic coal by heating it in an autoclave at about 750° F. and pressures in excess of 1000 psig to effect thermal restructuring. Thereafter the coal is cooled and condensable organic material is deposited on the lignite, stabilizing it and render it non-hygroscopic and more resistant to weathering and oxidation during shipment and storage. It is believed that the use of high temperature water drives off carboxylic acid groups and rendering those sites inactive to future activity with the active components of the fluid. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 4,214,875 (Coated coal piles) disclosed a coating composition to be applied to a pile of coal exposed to the weather in order to exclude rain and air by forming a continuous covering over the pile. The composition was normally thixotropic and included wax, tar or pitch or a polymer which provided a covering from one-quarter inch to one inch thick. It was necessary to break the covering in order to transfer or utilize the coal. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
Berkowitz in Canadian patent 959783, described a method of treating low-rank coals which included heating the coal to a temperature (about 350° C.) by immersion in a liquid medium, causing pyrolytic material to diffuse from the interior to the surface of the coal particles and to plug to pores to prevent moisture reabsorption. The entire disclosure of said Canadian patent is hereby incorporated by reference into this specification.
Wong disclosed in U.S. Pat. No. 4,461,624 (Beneficiation of low-rank coals by immersion in residuum) a process of immersing coal in residuum having a softening point of at least 80° C., at a temperature from about 240° C. to the decomposition temperature to boil off the moisture content and coat the coal particles within the immersion medium. This process has the disadvantages of providing a thick coating of treatment material on the coal particles which must be drained off of the particles.” The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 6,146,432 (Pressure Gradient Passivation of Carbonaceous Material Normally Susceptible to Spontaneous Combustion) describes a process for the passivation of a carbonaceous material by exposure to an oxygenated gas over a pressure gradient. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 4,170,456 (Inhibiting spontaneous combustion of coal char) discloses a treatment with air and carbon dioxide at temperatures from 50° F. to 300° F. to deactivate the surface of the coal char. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 4,192,650 (Process for drying and stabilizing coal) discloses a treatment that rehydrates the coal to a moisture level of 2-10 weight percent. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 5,527,365 (Irreversible drying of carbonaceous fuels) discloses a method for drying coal in a mildly reducing lower alkane gaseous atmosphere at a temperature of 150° to 300° C., with or without agglomeration with small amounts of oil. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 4,213,752 (Coal drying process) discloses a single-step process using in-situ generated thermal energy and causing partial combustion of the coal at atmospheric pressure in the presence of gas such as atmospheric air. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 4,043,763 (stabilization of dried coal) discloses a process of combining completely or partially dried coal with as-mined coal in a weight ratio of 1:2 to 10:1. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 3,723,079 (Stabilization of coal) discloses a process of treating dried coal with 0.5-8% oxygen by weight at a temperature of 175° C. to 225° C. and rehydrating the coal with water of from 1.5%-6% by weight of oxygen treated coal. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 4,249,909 (Drying and passivating wet coals and lignite) discloses a staged process of heating under low partial pressure of moisture to 8-12% moisture content then heated to a lower differential vapor pressure to remove additional moisture. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 3,896,557 (Process for drying and stabilizing coal) discloses a process of heating the coal in a fluidized combustion gas streat containing 7-9% by volume of oxygen to reduce moisture content to 8-12% by volume. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
The novel process described in this patent application provides a process for reducing the predisposition of coal to self-heat in the presence of oxygen. This novel, cost-effective and efficient process for irreversible drying and passivation of coal combines the advantages of the coating technology with the exposure of the coal to an oxygenated environment.
While the process taught in U.S. Pat. No. 6,146,432 requires a gradient of pressures, the novel process herein described can be done at atmospheric pressure and moderate temperatures in the range of 450-650 degrees Fahrenheit. U.S. Pat. No. 5,527,365 (Irreversible drying of carbonaceous fuels) teaches that processes involving high temperatures and pressures are economically undesirable, require substantial energy and capital investments and present inherent risks and dangers. The production costs are increased by specialized expensive equipment, apparatuses and facilities. The entire disclosure of said United States patent is hereby incorporated by reference into this specification.
U.S. Pat. No. 4,213,752 (Coal drying process) discloses advantages that are shared by the present invention through a new and novel process, “The process of the invention has the additional benefit that it is less costly because it uses the in-situ generated thermal energy for drying the added wet coal. This results from the fact that no capital investment is needed. Also, the system of the invention allows greater flexibility in the degree to which coal drying is made to occur because the coal stability is not critically sensitive to a particular moisture level and thus the product coal is very highly stable totally dry or with various moisture levels. Still further there is no need in the process of the invention for a rehydrating step which some prior art processes require to obtain a stabilized coal.” The entire disclosure of said United States patent is hereby incorporated by reference into this specification. | {
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1. Field of the Invention
The present invention is directed generally to multi-port or multi-outlet cassettes.
2. Description of the Related Art
Multiple communication ports or outlets may be housed inside a cassette that is mountable in a patch panel. Unfortunately, currently available cassettes suffer from a number of problems. For example, prior art cassettes lack optimal shielding of closely situated electrical connectors, sufficient connector density to support high connectivity demands, cable management and bend radius control as connector density increases, efficient patch panel latching mechanisms for multi-connector assemblies, as well as the ability to combine or mix conductive media (e.g., copper wires and optical fibers) in a single patch panel.
Therefore, a need exists for a low profile cassette configured to provide efficient high-density connectivity. In particular, a need exists for a cassette configured to house a plurality of one type of connector (e.g., copper wire connectors or optical fiber connectors) that is mountable in the same patch panel as one or more other cassettes configured to house the same or different types of connectors. A need also exists for cassettes configured to provide effective cable management and/or bend radius control. A cassette configured to provide improved and/or optimal shielding to reduce crosstalk between and among electrical connectors in close proximity within the cassette is also desirable. The present application provides these and other advantages as will be apparent from the following detailed description and accompanying figures. | {
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1. Field of the Invention
The present invention relates to pattern recognition and more particularly to a novel system which is useful in identifying shapes of various objects and patterns.
2. Description of Prior Art
According to a typical prior-art system of pattern recognition, the contour of an object under observation is first analyzed by the spatial analysis, followed by replacement of the analyzed contour line by infinitesimal line segments. Line functions of the line segments are then computed by the method of least squares, thereby to determine the edge lines.
Finding functions for infinitesimal line segments of a contour line, which is an essential part of the prior-art system, invariably involves very complicated time-consuming processes, requiring a sophisticated apparatus. Furthermore, any complicated shapes which are impossible to express in terms of line functions cannot be identified by a system of the type just discussed. | {
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1. Field of the Invention
The present invention pertains to the field of radar detection systems, more particularly to the field of radio wave based proximity fuzes including logic means. 342/68 or 102/215
2. Background of the Invention
A proximity fuze is an explosive ignition device used in bombs, artillery shells, and mines. The fuze senses when a target is close enough to be optimally damaged or destroyed by the weapon's warhead.
An example mission for a helicopter fired missile which includes a proximity fuze is to engage a small team of terrorists who possess a Short Range Air Defense (SHORAD) weapon (e.g. Red Eye, Stinger or SA-7) and intend to shoot down a commercial airliner. The missile is first aimed and then fired from the helicopter. Upon firing, the proximity fuze circuit is powered and enabled (armed). The missile may be guided or unguided during flight. Upon detecting signals indicating a proximal target, the fuze detonates the missile warhead. In such a missile, the proximity fuze may be designed in conjunction with the missile warhead to yield maximum effectiveness over a range of scenarios. In some scenarios the fuze may be required to ignore close encounters with terrain, buildings, or vegetation and yet reliably detonate proximal to the intended target.
Proximity fuzes can and have been based on acoustic, optical and radio frequency techniques. Acoustic is mostly applicable to torpedoes or mines. Optical techniques have issues with rain, smoke, and black targets and the like. Conventional radio frequency techniques include Doppler radar and radar amplitude signals. In addition, proximity fuzes have been based on conventional range gated radar. Conventional radio frequency and radar approaches are limited, however, for close range triggering in clutter environments because of difficulty achieving clutter rejection. Also, narrow band techniques are easily jammed by a small amount of RF power in band. Interference and jamming requirements must be considered in the design to avoid significant performance degradation in the field after substantial investment to deploy the weapon system.
Small missiles present an especially challenging set of systems requirements. Small missiles typically should detonate very close to the target within the lethality range of the small warhead, thus requiring close range precision fuzing. Missile flight may originate close to the ground or just above tree top and travel over or beside buildings or trees or ridges before arriving at the target area. In the target area, nearby structures or ground may need to be ignored while detecting the target and detonating at an appropriate range. Conventional RF techniques lack the resolution to achieve required performance in these complex engagements, especially in a very small package consuming a small amount of power.
Further system requirements include a long shelf life for the system including the power source. Small missiles are manufactured in large quantity and stored for twenty or more years where it is impractical to provide periodic maintenance including battery replacement.
Thus there is a need for an improved small size, long shelf life proximity fuze with short range precision fuzing capable of employing multiple target detection and discrimination methods for maximum effectiveness in complex engagements. | {
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A cholesteric liquid crystal will adopt a helical structure with the director rotating around an axis perpendicular to the substrate surfaces in an electro-optical cell with homogeneous alignment. Because of the self-assembled helical structure of cholesteric liquid crystal, in the planar texture where cholesteric helix is aligned vertically, the incident light is decomposed into its right and left circular components with one component reflected and the other transmitted. The unique ability of a cholesteric liquid crystal to reflect light comes from their helical superstructure. The central reflected wavelength (λo) in a direction normal to the surface can be described as λ0= n·p= n·(C·HTP)−1, where p is the helical pitch, in which the director rotates 360 degree, n is the average refractive index of the liquid crystal, C is the concentration of chiral dopant and HTP is the helical twisting power of the chiral material. The bandwidth (Δλ) of the reflected light equals Δnλ/ n, where Δn is the birefringence of liquid crystal and n is average of refractive index. A continuous tunable and electrically programmable optical filter based on cholesteric liquid crystal can be fabricated for filtering different spatial wavelength. The bandpass filters can achieve 100% transmission or reflection when a combination of two cholesteric filters with the same reflection wavelength and opposite handedness are stacked.
When the helical pitch of a cholesteric liquid crystal is adjusted to Bragg reflect in the visible spectrum, it reflects an iridescent color. Depending on the magnitude of an applied voltage, the cholesteric liquid crystal in an electro-optical cell can be switched to different optical states such as the planar to focal conic and planar to homeotropic in which the incident light is weakly scatted or totally transmitted, respectively. The cholesteric cell displays an image which can remain on a display permanently without an applied voltage. This memory phenomenon can be achieved either by using surface treatment or polymer stabilization, as detailed, e.g. in U.S. Pat. Nos. 5,437,811, 5,691,795 and 5,695,682
For example, in responding to an applied low voltage, a liquid crystal with positive dielectric anisotropy initially with a planar texture is transformed into the focal conic texture. The focal conic state is stable at zero voltage. Even the gray levels can be stable such that a display which has a combination of planar and focal conic will maintain that particular combination and hence level of reflectivity over an indefinite period of time. When the applied voltage is above the threshold necessary for unwinding the helix, the cholesteric liquid crystal is transformed into one with a homeotropic texture where ambient light is totally transmitted and the cells appears transparent. The homeotropic state reverts back to the initial planar state upon the quick removal of the applied voltage. When the surface of the back panel is painted black, both the focal conic texture and homeotropic states appear black. The color reflective planar texture and the transparent focal conic texture can be stable over a sufficiently long period of time such that an image can be addressed on a high resolution matrix display and the image will remain on the display after the voltage is removed.
A multicolor cholesteric display was first introduced by using a color pixelation technique with a combination of photo illumination tuned chiral material to adjust the helical pitch in the exposed regions to produce red, green and blue colors as seen in U.S. Pat. No. 5,668,614. While the feasibility has been demonstrated, there is a loss in reflective brightness. Another color reflective display technology was introduced shortly using vertical stacked RGB panels to achieve the multicolor and enhance the reflectivity. The brightness of the color panel is maximized by using a combination of left and right-handed circularly polarized cholesteric material in different panels. A full color cholesteric display with reflectivity exceeds 50% of the ambient incident light was reported in U.S. Pat. No. 6,654,080. The bottleneck for the full color cholesteric displays to be realized commercially resides in the production yield and cost. For example, to display a full color image it requires three color cholesteric films and electronic drivers which increase the cost of the display. Furthermore, the shift register of pixels from separate panels causes parallax problem. Parallax demands that the thickness of the stacked layers be thinner than the pixel size. As a result, the yield in producing full color displays is low because of complexity in manufacturing process.
An alternative method to produce full color reflective cholesteric display involves the use of electrically tunable color technology. It is not anticipated that the focal conic state be used in which the switched color requires the voltage to remain on to display the desired color. The electric-field induced color change in cholesteric liquid crystals color can be traced back to the 1960's. Because the relationship of λo= n p cos θ, the increase in tilt angle of cholesteric helix observed 15° from normal to the surface in response to applied voltage results in a smaller cholesteric pitch and thus, the spectral wavelength is blue shifted. Pitch dilation in cholesteric liquid crystal in which the color changes from blue to red with an increase in an applied field has been noted. In general, the cholesteric liquid crystal response to applied voltage by the rotation of the cholesteric helix away from normal direction of substrate surface. Without strong surface anchoring, there are insufficient cholesteric pitches to reflect incoming light in the normal direction. Consequently, these methods yield low reflectivity and short spectrum tuning range.
Another electrically-tuned color technology utilizes a display with in-plane inter-digitized electrodes configured on one surface and only LC alignment layer on the other surface without electrode as described in U.S. Pat. No. 6,630,982. The device enables an inhomogeneous distribution of electric field across the cell thickness and unwinds and elongates the cholesteric helix when an appropriate voltage is applied to the inter-digitized electrodes. Using a positive dielectric anisotropy cholesteric, the cholesteric pitch is extended with the increase in applied voltage. To achieve high reflectivity for each switched color, this display requires a thick cell. As a consequence, high switching voltage and slow response time are major challenges associated with the in-plane switched color technique.
The use of gel to preserve the polymer structure and uniform distribution of polymer within the cell has been reported. With a polymer consisting of mesogenic diacrylate and monoacrylate, the gel enables a shift in reflection band to low wavelength with increasing voltage, which was associated with the tilting of the cholesteric helix. In a second case, with a chiral monoacrylate additive, the reflection band is not shifted but reduces the reflectivity with increasing voltage, which is associated with Helfrich deformation following unwinding the helices. The negative aspects include broadening of reflective bandwidth and low reflectivity. The use electrical-field induced color change in cholesteric liquid crystal has been described using Helfrich deformation. The field-induced change in optical property of the cholesteric reactive mesogen is photopolymerized and fixed on a polymer film by masked curing the cholesteric reactive mesogen at different voltages. The negative aspects of this approach are a multicolor static film with loss of reflectivity at normal direction and broadening of spectral wavelength.
It would therefore desirable to provide a technique for fabricating cholesteric liquid crystal light modulating devices in which the spectral wavelength can be electrically switched, and for displays with all of the mentioned benefits, which can be practically implemented. | {
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1. Field of the Invention
The present invention relates to a nonaqueous electrolyte rechargeable battery including a positive electrode, a negative electrode and a nonaqueous electrolyte, and more particularly to a nonaqueous electrolyte rechargeable battery using molybdenum oxide for positive electrode material.
2. Description of Related Art
Currently available rechargeable lithium batteries use lithium cobaltate (LiCoO2) or lithium manganate (LiMn2O4) for the positive electrode material and carbon materials for the negative electrode material. However, applications such as portable equipment demand rechargeable batteries capable of longer operation and thus having increased capacities and energy densities. Also, there has been a need in the art for alternative materials to lithium cobaltate which is a rare and expensive resource while being the most popular positive electrode material currently used.
Molybdenum oxide is considered to be a possible alternative to lithium cobaltate. In lithium cobaltate, an oxidation number of cobalt changes from trivalent to tetra-valent. An oxidation number of molybdenum, on the other hand, is changeable between tetravalent and hexavalent in molybdenum oxide. Accordingly, the use of molybdenum oxide in place of lithium cobaltate is expected to increase both capacities and energy densities of rechargeable batteries.
However, in the current state of the art, rechargeable lithium batteries using molybdenum oxide in place of lithium cobaltate only present the discharge capacity lower than the theoretical capacity. Japanese Patent Laying-Open Nos. Hei 11-250907 and Hei 3-88269 propose the use of molybdenum oxide in the amorphous form. However, resulting capacity and energy density have been still insufficient.
Also, it is known that when Li ions are inserted into molybdenum oxide, such Li ions move into spaces between layers composed of Mo and O and further into interiors of those layers to destruct them (See, for example, T. Tsumura and M. Inagaki, Solid State Ionics, vol.104 (1997), pp 183-189). This is considered due to the weak bond of Mo and O and has caused a problem of capacity decline with cycling for nonaqueous electrolyte rechargeable batteries using conventional molybdenum oxide for the positive electrode material. Since such a declining capacity with cycling is attributed basically to the weak bond between Mo and O the use of molybdenum oxide having an amorphous or other non-laminar crystal structure has also resulted in the capacity reduction with cycling.
It is an object of the present invention to provide a nonaqueous electrolyte rechargeable battery which uses molybdenum metal oxide for its positive electrode material, which has improved capacity and energy density and which exhibits excellent cycle performance characteristics.
The present invention provides a nonaqueous electrolyte rechargeable battery having a positive electrode, a negative electrode and a nonaqueous electrolyte. Characteristically, the positive electrode comprises molybdenum metal oxide deposited, in the form of a thin film, on an aluminum-containing substrate and represented by the formula Mo1xe2x88x92xMxO2+y (where M is at least one element selected from the group consisting of Ni, Co, Mn, Fe, Cu, Al, Mg, W, Sc, Ti, Zn, Ga, Ge, Nb, Rh, Pd and Sn, x satisfies the relationship 0.005xe2x89xa6xxe2x89xa60.5, and y satisfies the relationship 0.6xe2x89xa6yxe2x89xa61.2).
The molybdenum metal oxide used, in the form of a thin film, for the positive electrode in accordance with the present invention is represented by the formula Mo1xe2x88x92xMxO2+y, i.e., the molybdenum metal oxide derived via partial substitution of a metal element for Mo in molybdenum oxide. The substituting metal element M is at least one element selected from the group consisting of Ni, Co, Mn, Fe, Cu, Al, Mg, W, Sc, Ti, Zn, Ga, Ge, Nb, Rh, Pd and Sn. The partial substitution of metal element M for Mo increases a bond strength between the metal element and oxygen to thereby improve cycle characteristics. Preferably, the substituting element M is at least one element selected from the group consisting of Ni, Co, Mn, Fe, Al, Mg, W and Ti.
In the above-specified formula, x is a stoichiometric value of the substituting element M and satisfies the relationship 0.005xe2x89xa6xxe2x89xa60.5, preferably 0.01xe2x89xa6xxe2x89xa60.3. If the value of x falls outside the specified range, the sufficient improvement in cycle characteristics, which is an effect of the present invention, may not be obtained.
In the above-specified formula, y indicates a variation in stoichiometry of oxygen and satisfies the relationship 0.6xe2x89xa6yxe2x89xa61.2. If y is maintained at a value within this range, nonaqueous electrolyte rechargeable batteries result having improved capacities and energy densities.
A substrate surface over which the molybdenum metal oxide thin film is to be deposited contains aluminum and specifically comprises an aluminum metal or aluminum alloy. Preferably, the thin film may be deposited on the substrate by using a thin film-forming technique such as a CVD, sputtering, vacuum deposition, spraying process or the like.
In the present invention, the substrate preferably serves as a current collector for an electrode. Also, the substrate surface over which the molybdenum metal oxide thin film is to be deposited preferably has a surface roughness Ra in the range of 0.001-1 xcexcm. If the substrate having such a surface roughness Ra is used, the substrate serving as a current collector can maintain good adhesion to the molybdenum metal oxide thin film even during its expansion or shrinkage on charge-discharge cycling and thus collect current efficiently. The surface roughness Ra is defined by Japan Industrial Standards (JIS B 0601-1994) and can be determined as by a surface roughness meter.
In the present invention, the surface roughness Ra of the substrate preferably satisfies the relationship Raxe2x89xa6t, where t is a thickness of the molybdenum metal oxide thin film.
Also in the present invention, the surface roughness Ra of the substrate preferably satisfies the relationship Sxe2x89xa6100Ra, where S is an average interval of peaks in surface irregularities. The average peak interval S is also defined by Japan Industrial Standards (JIS B 0601-1994) and can also be determined as by a surface roughness meter.
In the present invention, the surface roughness Ra of the substrate is more preferably in the range of 0.0105 xcexcm and greater, still more preferably in the range of 0.011-0.1 xcexcm, still more preferably in the range of 0.012-0.09 xcexcm. The use of the substrate having a surface roughness Ra within the above-specified range enables structural control of the molybdenum metal oxide thin film deposited thereon, resulting in the formation of an electrode which exhibits improved cycle characteristics. That is, by depositing the molybdenum metal oxide thin film on the substrate roughened at its surface to the specified surface roughness Ra, the structure of the molybdenum metal oxide thin film can be rendered into such a form that enhances its adhesion to the substrate as a current collector. | {
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Commonly employed security systems, such as used in museums, art galleries, shops, safe deposit vaults, banks or the like, do not protect each of the objects of value therein as such objects are generally too numerous or too small or cannot be altered to provide the necessary supports for the attachment of security devices. The usual security system solves this problem by concentrating a protection on the case in which the object is displayed, the room in which objects are stored, or the room or building in which the objects are contained. In addition, common security devices are far too expensive for the protection of individual objects, except in instances where only a small number of objects are being protected, or in instances wherein the objects are extremely valuable.
The commonly known type of security system has certain disadvantages. To begin with, the object is specifically what should be protected from thieves or vandals and not the case, room or building in which the object is accommodated. Moreover, false alarms arise too frequently due to occurrences which are not attempts to steal or damage the protected objects, but which are instead accidents, negligence or other occurrences involving the case, room or building accommodating the object. Such occurrences include accidental breaking of windows and the like that should, of course, be investigated by security personnel, but which do not constitute a true alarm situation or alert because of the lack of threat to the object being protected.
Another disadvantage of commonly used security systems is their failure to protect objects which are not located within cases and are accessible to the public during some part of the day. To distinguish between touching and stealing is almost impossible, or in most cases, prohibitively expensive. Touching, while not allowed, is a commonplace occurrence but does not constitute an act which requires setting off an alarm. On the other hand, stealing a painting hung on a wall requires the removal of the same and frame or the cutting of the painting out of the frame leaving the frame mounted on its supporting wall as before. Known systems cannot protect such an object while allowing access to the object for reasons of viewing and appreciation.
U.S. Pat. No. 666,737 shows a burglar alarm system in which is employed the combination of a vault or other like structure, the walls of which are impervious to waves of radiant energy, there being a sensitive electrical device arranged within the vault or other such structure, and adapted to operate upon the admission of such radiant energy through an opening or entrance in such walls, and an electrical signal appliance controlled by such sensitive device. Herein, as distinguished from the invention to be disclosed hereinafter, the protection while ultimately afforded to the object or objects themselves is predicated upon the interference with radiant energy of the walls of the structure surrounding the object to be protected.
U.S. Pat. No. 3,886,351 provides a photo-responsive means in an interface circuit, which photo-responsive means is positioned to receive light signals for developing electrical output signals as a function of the received light energy. A first differential amplifier is connected to receive the electrical output signals as a first input, and a known fixed reference as a second input. The first differential amplifier generates first and second output signals having a differential therebetween as a function of the differential between its received inputs. First and second unidirectional current paths connect the first and second output signals of the first differential amplifier as inputs to a second differential amplifier. Although the circuit disclosed employs a comparison with a fixed reference, this is unlike the comparison employed in accordance with various embodiments of the invention as will become apparent hereinafter.
U.S. Pat. No. 3,813,540 relates to a circuit for optically sensing coded data on a record medium and including a photosensitive transducing means. In order to render the circuit independent of background brightness variations, provision is made of load impedance, particularly arranged so that the voltage drop is proportional to the natural logarithm of current flowing through the transducing element. The voltage difference resulting from sensing contrasting marks on the record medium depends only on the contrast in reflected light and not on the absolute value of current on the transducing element. This particular disclosure relates generalized features which may be employed in accordance with the invention, but does not use these features for security systems as will be discussed hereinafter. | {
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1 Field of the Invention
This invention relates to antenna constructions and more particularly to a wire carrier clip for providing an improved method and means for attaching lead wires to the antenna.
2 Description of the Prior Art
Most antenna installations in the home TVRO industry have no means of attaching the receiving cables to the antenna. It is largely left up to the imagination of the installer as how best to attach the antenna lead wires. Most installers use plastic tie wraps to secure the lead wires, drilling holes in the antenna mesh or antenna ribs for attachment.
Tie wraps usually don't last long in the weather conditions of an outside installation. Consequently, important wires are caused to dangle and are left unattached. | {
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Fuses have found wide applications in industry and the home and are designed to prevent an excessive overload of current from damaging electrical equipment. In the most basic form an electrical fuse comprises a fusible link or fuse element connected between electrical conducting members which are intended to be inserted in series with the circuit serving the electrical equipment. In operation the fuse element functions in response to an excessive amount of current by opening the circuit to prevent damage of the equipment.
More advanced types of fuses have mechanical operating apparatus combined with fuse elements to effect the opening of a protected electrical circuit. For example, one such type of fuse device utilizes a disk contact structure to open the electrical circuit. The disk contact is controlled by the melting and voluminous expansion of a temperature sensitive member responding to an excessive amount of electrical current. Other types of fuse devices employ spring apparatus in combination with a fuse element to form a contact structure that operates to open the protected circuit when excessive current melts the fuse element. A problem with these types of fuse devices is that the mechanical operating apparatus and fuse elements are positioned within an electrical conducting casing or housing that prevents a visual inspection as to the operative or inoperative state of the fuse.
Alarm indicating fuses have been disclosed in the prior art and are designed to provide a visual indication when the fuse element operates to open the protected electrical circuit. Such a fuse device typically comprises a pair of electrical conducting members each located on the end of an insulative housing having a fuse element positioned therein. The fuse element coupled to one of the electrical conducting members is connected through a spring member located outside the insulative housing to the other electrical conducting member. An electrical path extends from the one electrical conducting member through the fuse element and spring member to the other electrical conducting member. Excess current flowing through the path opens the fuse element to interrupt the protected electrical circuit and release the spring member to visibly indicate the inoperative state of the fuse. A problem arises with this type of fuse device in that the conducting spring member adds resistance in the electrical path and increases the temperature of the fuse device thereby limiting use to specific applications.
Accordingly, a need exists for an alarm indicating fuse for both low and high current electrical circuit applications. A need also exists for an alarm indicating fuse designed to both lower the resistance of the electrical path and the total wattage output of the fuse to thereby improve use for both low and high current circuit applications. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to metal catalysts, especially to catalysts which comprise platinum, zinc and at least one of nickel and iron, which are useful in fuel cell electrodes and other catalytic structures.
2. Background Information
A fuel cell is an electrochemical device for directly converting the chemical energy generated from an oxidation-reduction reaction of a fuel such as hydrogen or hydrocarbon-based fuels and an oxidizer such as oxygen gas (in air) supplied thereto into a low-voltage direct current. Thus, fuel cells chemically combine the molecules of a fuel and an oxidizer without burning, dispensing with the inefficiencies and pollution of traditional combustion.
A fuel cell is generally comprised of a fuel electrode (anode), an oxidizer electrode (cathode), an electrolyte interposed between the electrodes (alkaline or acidic), and means for separately supplying a stream of fuel and a stream of oxidizer to the anode and the cathode, respectively. In operation, fuel supplied to the anode is oxidized, releasing electrons which are conducted via an external circuit to the cathode. At the cathode, the supplied electrons are consumed when the oxidizer is reduced. The current flowing through the external circuit can be made to do useful work.
There are several types of fuel cells, including those having electrolytes of: phosphoric acid, molten carbonate, solid oxide, potassium hydroxide, and proton exchange membrane. A phosphoric acid fuel cell operates at about 160-220° C., and preferably at about 190-200° C. This type of fuel cell is currently being used for multi-megawatt utility power generation and for co-generation systems (i.e., combined heat and power generation) in the 50 to several hundred kilowatts range.
In contrast, proton exchange membrane fuel cells use a solid proton-conducting polymer membrane as the electrolyte. Typically, the polymer membrane is maintained in a hydrated form during operation in order to prevent loss of ionic conduction which limits the operation temperature typically to between about 70 and about 120° C. depending on the operating pressure, and preferably below about 100° C. Proton exchange membrane fuel cells have a much higher power density than liquid electrolyte fuel cells (e.g., phosphoric acid), and can vary output quickly to meet shifts in power demand. Thus, they are suited for applications such as in automobiles and small scale residential power generation where quick startup is a consideration.
In some applications (e.g., automotive) pure hydrogen gas is the optimum fuel; however, in other applications where a lower operational cost is desirable, a reformed hydrogen-containing gas is an appropriate fuel. A reformed-hydrogen containing gas is produced, for example, by steam-reforming methanol and water at 200-300° C. to a hydrogen-rich fuel gas containing carbon dioxide. Theoretically, the reformate gas consists of 75 vol % hydrogen and 25 vol % carbon dioxide. In practice, however, this gas also contains nitrogen, oxygen, and, depending on the degree of purity, varying amounts of carbon monoxide (up to 1 vol %). Although some electronic devices also reform liquid fuel to hydrogen, in some applications the conversion of a liquid fuel directly into electricity is desirable, as then a high storage density and system simplicity are combined. In particular, methanol is an especially desirable fuel because it has a high energy density, a low cost, and is produced from renewable resources.
For the oxidation and reduction reactions in a fuel cell to proceed at useful rates, especially at operating temperatures below about 300° C., electrocatalyst materials are typically provided at the electrodes. Initially, fuel cells used electrocatalysts made of a single metal, usually platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), osmium (Os), silver (Ag) or gold (Au) because they are able to withstand the corrosive environment—platinum being the most efficient and stable single-metal electrocatalyst for fuel cells operating below about 300° C. While these elements were first used in fuel cells in metallic powder form, later techniques were developed to disperse these metals over the surface of electrically conductive supports (e.g., carbon black) to increase the surface area of the electrocatalyst which in turn increased the number of reactive sites leading to improved efficiency of the cell. Nevertheless, fuel cell performance typically declines over time because the presence of electrolyte, high temperatures and molecular oxygen dissolve the electrocatalyst and/or sinter the dispersed electrocatalyst by surface migration or dissolution/re-precipitation.
Although platinum is the most efficient and stable single-metal electrocatalyst for fuel cells, it is costly and an increase in electrocatalyst activity over platinum is necessary for wide scale commercialization of fuel cell technology. The development of cathode fuel cell electrocatalyst materials faces longstanding challenges. The greatest challenge is the improvement of the electrode kinetics of the oxygen reduction reaction. In fact, sluggish electrochemical reaction kinetics have prevented attaining the thermodynamic reversible electrode potential for oxygen reduction. This is reflected in exchange current densities of around 10−10 to 10−12 A/cm2 for oxygen reduction on, for example, Pt at low and medium temperatures. A factor contributing to this phenomenon include the fact that the desired reduction of oxygen to water is a four-electron transfer reaction and typically involves breaking a strong O—O bond early in the reaction. In addition, the open circuit voltage is lowered from the thermodynamic potential for oxygen reduction due to the formation of peroxide and possible platinum oxides which inhibit the reaction. A second challenge is the stability of the oxygen electrode (cathode) during long-term operation. Specifically, a fuel cell cathode operates in a regime in which even the most unreactive metals are not completely stable. Thus, alloy compositions which contain non-noble metal elements may have a rate of corrosion which would negatively impact the projected lifetime of a fuel cell. The corrosion may be more severe when the cell is operating near open circuit conditions (which is the most desirable potential for thermodynamic efficiency).
Electrocatalyst materials at the anode also face challenges during fuel cell operation. Specifically, as the concentration of carbon monoxide (CO) rises above about 10 ppm in the fuel the surface of the electrocatalyst can be rapidly poisoned. As a result, platinum (by itself) is a poor electrocatalyst if the fuel stream contains carbon monoxide (e.g., reformed-hydrogen gas typically exceeds 100 ppm). Liquid hydrocarbon-based fuels (e.g., methanol) present an even greater poisoning problem. Specifically, the surface of the platinum becomes blocked with the adsorbed intermediate, carbon monoxide (CO). It has been reported that H2O plays a key role in the removal of such poisoning species in accordance with the following reactions:Pt+CH3OH→Pt—CO+4H++4e− (1);Pt+H2O→Pt—OH+H++e− (2); andPt—CO+Pt—OH→2Pt+CO2+H++e− (3).As indicated by the foregoing reactions, the methanol is adsorbed and partially oxidized by platinum on the surface of the electrode (1). Adsorbed OH, from the hydrolysis of water, reacts with the adsorbed CO to produce carbon dioxide and a proton (2,3). However, platinum does not form OH species well at the potentials fuel cell electrodes operate (e.g., 200 mV-1.5 V). As a result, step (3) is the slowest step in the sequence, limiting the rate of CO removal, thereby allowing poisoning of the electrocatalyst to occur. This applies in particular to a proton exchange membrane fuel cell which is especially sensitive to CO poisoning because of its low operating temperatures.
One technique for increasing electrocatalytic cathodic activity during the reduction of oxygen and electrocatalytic anodic activity during the oxidation of hydrogen is to employ an electrocatalyst which is more active, corrosion resistant, and/or more poison tolerant. For example, increased tolerance to CO has been reported by alloying platinum and ruthenium at a 50:50 atomic ratio (see, D. Chu and S. Gillman, J. Electrochem. Soc. 1996, 143, 1685). The electrocatalysts proposed to date, however, leave room for further improvement. | {
"pile_set_name": "USPTO Backgrounds"
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An important aspect of modern power supply design is the need to increase the power density of the power supply since many power applications involve locations in which the size of the power supply relative to its power output is restricted by space considerations. The power train and control circuits in addition to being highly compact must also have high overall efficiency to limit heat creating power dissipation. An illustrative application of a high density power supply is an off-line power supply used to power a laptop computer or similar appliance. Bridge type converters are suitable for such applications since they may be designed to operate resonately, which is an operational mode permitting a very high power density and high power efficiency.
The power switching transistors in a half bridge converter have an applied voltage stress half that of the switching transistors in a push-pull converter of comparable power handling capability. Hence the half bridge converter is especially suitable for high input voltage applications such as power converters powered directly from a rectified AC power line or from a power factor correction boost converter powered off the AC line.
Synchronous rectifiers are used in power supplies requiring high efficiency since they have little loss in operation. Proper drive circuits must be provided to drive the synchronous rectifier devices. Power supplies are often connected in parallel and without proper drive arrangements a synchronous rectifier of a failed power supply may be improperly biased into operation allowing a reverse feed to power into the power supply. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field
The present disclosure relates generally to water areas and, in particular, to managing water areas. Still more particularly, the present disclosure relates to a method and apparatus for monitoring and responding to safety related events in a recreational water area.
2. Background
Recreational water areas such as beaches and the water around the beaches are areas in which lifesaving operations may be performed for people involved in various activities at and around the beaches in these recreational water areas. For example, over 70,000 individuals are rescued each year from imminent peril at various beaches in the United States. Rescues may occur for individuals who are unable to swim in ocean waters, caught in rip currents, and/or encounter other conditions that may occur in the water.
These rescue missions involve lifeguards at the beaches. Lifeguards may be stationed at various lifeguard stands and other stations. Additionally, lifeguards also may move on vehicles to different locations to monitor the water in which recreational activities occur by the beaches.
The use of lifeguards is an expensive but necessary cost. With the use of lifeguards, however, the cost may restrain time periods when lifeguards are available. For example, lifeguards may only be available during normal operating hours of the beaches. After the normal operating hours, a smaller workforce of lifeguards may be present to monitor the same recreational water area. In some cases, after normal operating hours, lifeguards may be absent from the beaches. Moreover, less popular beaches may not be monitored at all.
As a result, individuals who use recreational water areas outside of normal operating hours or use recreational water areas where lifeguards are not present may find it more difficult to obtain assistance when needed. The absence or reduced number of lifeguards may make it more difficult to detect when individuals may need assistance after normal operating hours for a recreational water area.
Additionally, a desired number of trained lifeguards may be unavailable for use in recreational water areas. For example, even when funds are available for use to expand coverage areas or hours of operation for lifeguard services, the number of certified lifeguards available to work in the recreational water area may be fewer than desired. As a result, lifeguard services in the recreational water area may not be as effective as desired.
Further, even when more lifeguards are present during normal operating hours, the number of lifeguards monitoring a beach may not provide as much coverage as desired to monitor for events in which individuals may need assistance. For example, physical limitations of a lifeguard may limit the effectiveness of lifeguards in the recreational water area. As an example, a lifeguard may have difficulty seeing out into the water to identify that an individual is drowning at about 500 meters away. Further, even if the lifeguard does identify that the individual may be drowning, the time for the lifeguard to reach the individual may be more than desired. As a result, lifeguards may not identify all events in all of the different locations on the beach as quickly as desired and may not reach individuals needing assistance as quickly as desired.
Therefore, it would be desirable to have a method and apparatus that takes into account at least some of the issues discussed above, as well as other possible issues. | {
"pile_set_name": "USPTO Backgrounds"
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Prior art security systems for electronic and other devices require the entry of a code at a keypad to allow the device to be used. One such security system is described in U.S. Pat. No. 4,604,708, entitled "Electronic Security System for Externally Powered Devices," by Gainer R. Lewis. This patent describes a security system, wherein the user must reenter a code whenever the protected device is reconnected to a power source. However, the user does not have to reenter the code each time the power switch is turned on and off. When the correct code is entered, power is then coupled to the protected device. Other security systems, such as home alarm or car entry systems require the user to enter the code upon each entry attempt.
The problem with coded security systems, such as that described above, is that the user often forgets the password provided by the manufacturer. Further, the user cannot easily program the password to make it easier to remember, like a significant other's name, or immediately program the password to prevent others who know the password from accessing the protected device.
Still further, users may want to require password entry upon each use, such as to protect a car, house, etc, not only when the protected unit is reconnected to a power source. Requiring manual entry of the password for each use would be tedious. To make it easy for the user to enter the password upon each use, current security systems, such as car alarms, allow the user to disable the alarm from a remote activation unit. However, these remote devices are not easily and immediately programmable. With prior art remote activation units, the user is relying on passwords selected by the manufacturer which are pre-installed in both the protected unit and the remote activation unit. Furthermore, the user must rely on the manufacturer to provide a properly coded replacement remote activation unit. This situation may be problematic because in many instances it may be difficult or unfeasible for the user to contact the manufacturer and immediately program the password or obtain a new activation unit.
Alternatively, some prior art systems allow the user to manually change the password code stored in the protected unit and activation unit by pushing switches to an on/off position. However, these systems too are problematic because anyone who can gain physical access to the switches can program the password.
The problem with present security systems can be illustrated with the current situation in the car stereo market. Some car stereos require the entry of a code only when the car stereo is reconnected to the battery. The problem with this system is that if the user gets a battery recharge a considerable time after writing down the password, the user may not have the password readily available when it is needed, i.e., when they get "jump started" on an automobile trip far from home. In such case, the user cannot use the car stereo until the manufacturer is contacted and provides the code. This set-up could be extremely inconvenient, especially if the password is lost on a holiday weekend or in a location where the manufacturer may not be easily contacted.
Other car stereos have a removable face plate which prevents the stereo from being used. However, the removable face plate also has problems. The face plate is bulky and, thus, a burden for the driver to have to carry every time the driver leaves the car. Moreover, the face plate is very expensive to replace. In fact the replacement cost is a significant portion of what the entire car stereo cost in the first place.
Still further, none of the current car stereo systems allow the user to access the car stereo using a remote activation or allow the user to easily program the security code in both the car stereo and remote activation unit. | {
"pile_set_name": "USPTO Backgrounds"
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Design and graphics related applications, such as Adobe® Illustrator®, typically provide various ways for a user to specify or otherwise select color, including text based and graphical color pickers. Examples of text based color pickers include input boxes for entering RGB (Red, Green, Blue), CMYK (Cyan, Magenta, Yellow, Black), and HSB (Hue, Saturation, Brightness) values for a particular color. Examples of graphical color pickers include color sliders, color wheels, and color grids. Color pickers typically display a continuous spectrum of colors from which a user can choose.
There are cases in which users are limited to a particular set of allowed colors due to physical or other constraints. For example, users who work in print, silk screening, and branding often must work with a particular color library comprising of a finite number of colors. A continuous spectrum color picker is less useful in that it will pick colors outside of the allowed color set. If a user uses the Pantone library, for example, the user typically must first specify a color from a continuous spectrum color picker, and then request the closest Pantone color to that color. If the returned Pantone color is not desirable to the user, the user goes back, specifies another color from the continuous spectrum color picker, and again requests the closest Pantone color to that color. This process continues until a desirable Pantone color is returned. Only one Pantone color can be requested at a time. Thus, a Pantone color is selected by trial and error, testing out a series of guesses until a desirable Pantone color is found. This process is repetitive, inefficient, and may yield a suboptimal result. For example, a frustrated user may simply make do with an unsatisfactory color rather than waste time trying to find a better color. This process is also extremely tedious when attempting to find a set of related colors within the Pantone set. Since the user is navigating the continuous spectrum of colors using a color picker the user is unable to answer questions like, “What is the next greenest Pantone color?” or “What is the next most saturated Pantone color?” Thus, improved techniques for color selection are needed. | {
"pile_set_name": "USPTO Backgrounds"
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Unless otherwise indicated herein, the description in this section is not prior art to the claims in this application and is not admitted to be prior art by inclusion in this section.
The disclosure relates to a fixing device that employs a belt fixing method where a paper sheet carrying an unfixed toner image is inserted into a fixing nip portion, which is formed by a heated fixing belt and a pressure member, and the unfixed toner is heated and melted for fixation on the paper sheet. The disclosure also relates to an image forming apparatus including the fixing device employing an electrophotographic method.
In the conventional image forming apparatus that employs the electrophotographic method, the following belt fixing method has been developed. Instead of a heating roller, an endless fixing belt that absorbs radiant heat from a heat source and generates heat is employed as a heating member for heating the paper sheet. The paper sheet carrying an unfixed toner image is inserted into a fixing nip portion formed by the heated fixing belt and a pressure member, which is brought into pressure contact with the fixing belt, thus a toner is fixed on the paper sheet.
In this belt fixing method, at least one of a fixing roller pair forming the fixing nip portion is used as a heating roller. Inserting the paper sheet carrying the unfixed toner image into the fixing nip portion can decrease thermal capacity and shorten a warm-up period, thus reducing power consumption, compared with a heat roller fixing method fixing a toner on a paper sheet.
The following methods for driving the fixing belt are known, for example. Flange-shaped end cap members are secured on both ends of the endless fixing belt in a rotation shaft direction. The fixing belt is driven via a gear formed at the end cap members. Alternatively, the fixing belt is driven with a suspension roller disposed downstream of a nip portion inside of the endless fixing belt.
However, with the above-described method of directly driving the fixing belt, pressing members, such as the end cap member and the suspension roller disposed inside of the fixing belt, may need to be rotated. Accordingly, it was difficult to freely configure a shape and a width of the nip portion.
As a method for expanding a nip width, for example, a method of using a pressure roller with large diameter, a method of increasing rubber thickness or reducing rubber hardness at a surface of the pressure roller, or a method of enhancing pressing force by the pressure roller are generally known. However, the pressure roller with large diameter may result in large-size fixing device and a cost increase, whereas an increase in rubber thickness may result in extension of the warm-up period. Reduction in rubber hardness increases a change in outer diameter due to temperature, causing reduction in conveyability, also degrading durability. Further, elevation in the pressing force by the pressure roller leads to reduction in conveyability due to excessive amount of deflection of the roller surface and a cost increase due to reinforcement of a fixing frame.
Therefore, the following sliding-belt fixing method has been devised. A supporting member is disposed inside of the fixing belt. A pressure roller is brought into pressure contact with the supporting member from outside of the fixing belt. At the same time, a friction force between the pressure roller and the outer surface of the fixing belt slides the supporting member and the inner surface of the fixing belt, thus rotating the fixing belt.
The following fixing device has been disclosed, for example. The fixing device includes a fixing belt, a radiant heat source (halogen heater) inside of the belt, a supporting member with a sliding surface, and a pressure roller. Rotatably driving the pressure roller to slide a fixing belt and the supporting member at a nip portion formed by the fixing belt and the pressure roller, thus rotating the fixing belt.
With the above-described sliding-belt fixing method, to rotate the fixing belt smoothly, slidability between the fixing belt and the supporting member may need to be ensured. Accordingly, another fixing belt has been disclosed. A sliding layer, which forms a sliding surface on a side sliding along the supporting member of the fixing belt (inner circumferential surface), is disposed. This ensures the improved wear resistance and slidability of the belt inner circumferential surface. | {
"pile_set_name": "USPTO Backgrounds"
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Famously referred to by National Geographic as “the most dangerous eight seconds in sports,” bull riding pits an athlete 20 one-on-one against a bull 24 weighing as much as 2000 pounds in a showdown so hazardous that one or two bull riders 20 per year lose their lives to the competition. Notwithstanding the ever present peril, however, and much to the excitement of nearly two million annual live event attendees and another 100 million annual television viewers, bull riders 20 are spurred on by the thrill of the action, and the desire to test their skills, tenacity and daring against the mighty bulls 24, to continue to participate in the sport. With the sport likely only to increase in fan popularity and rider participation, improvements in rider safety become ever more important.
To this end, promoters of bull riding have gone to great lengths to provide the bull riders 20 with additional protection from the bulls. For example, improved helmets and a specially designed protective vest 23 have greatly contributed to a reduced injury rate. Unfortunately, however, one danger that persists notwithstanding its often tragic consequences is the risk that the bull rider 20 will be unable to successfully free his or her riding hand 21 from the bull rope 29 during dismount, especially in the case of being bucked off from the bull 24. When such a “hang up” happens, the bull rider 20 is almost never able to reach the bull rope 29 with his or her free hand 22 and, as a result is completely dependent on the bullfighters or horsemen for what is very likely lifesaving assistance. Until the bullfighters and horsemen are able to reach the bull 24 and gain control over the bull rope 29, however, the bull rider 20 is in grave danger of being trampled by the bull 24 or slammed into the arena fence or bull chutes. In any of these situations, serious injury or death is a very probable result.
With the shortcomings of the prior art clearly in mind, it is therefore an overriding object of the present invention to provide a method and apparatus through which a harness may be quickly and reliably removed from an animal, removal therefrom being possible through remote control. | {
"pile_set_name": "USPTO Backgrounds"
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Mechanical equipment refers to a machine or machinery that is formed of a defined arrangement of multiple components. A component may represent a part, an assembly of parts, a subassembly of a part, an element, or another constituent of a machine. A component is not limited to mechanical elements and is broadly defined to include an electrical assembly, an electrical system, an electronic system, a computer controller, software, or the like. Mechanical equipment includes heavy equipment and capital-intensive equipment that is movable or fixed. Mobile mechanical equipment includes airplanes, busses, locomotives, ships, cranes, heavy trucks, earth-moving equipment, or the like. Fixed mechanical equipment includes electrical power generators, industrial presses, manufacturing equipment, or the like.
A configuration defines the identity of the components (e.g., parts), a specification of the components, and the relationship among the arrangement of components of the mechanical equipment, among other things. Because some components are interchangeable with substitutes, the configuration of mechanical equipment may vary throughout a life span of the mechanical equipment as equipment-related work (e.g., maintenance, repair, or overhaul work) is performed. The configuration of mechanical equipment may change because of a revision of product definitions or a review (e.g., a financial and performance review) of the mechanical equipment. Further, even during the manufacturing process, the manufacturer of the mechanical equipment may substitute different components (e.g., parts) from different suppliers to customize the mechanical equipment, to meet a certain technical specifications for the mechanical equipment, or to save manufacturing costs on the mechanical equipment. For example, the manufacturer may change technical specifications of mechanical equipment to rectify manufacturing anomalies or to facilitate more reliable production. Thus, standard as-built documentation on the mechanical equipment may contain erroneous information on the configuration of the equipment.
Maintenance, overhaul and repair personnel may keep few records of the actual configuration of the equipment because of over-reliance on the manufacturer's specifications, manuals, and as-built documentation. Even if configuration records are available, the records may be difficult to use or access. Thus, a need exists for promoting the maintenance of accurate records on equipment-related work with ready access to maintenance, overhaul and repair personnel.
In the context of an airplane as the mechanical equipment, the airplane may be viewed as a member of a fleet subject to the fleet specifications in general manuals, rather than a unique configuration. If generalizations from the fleet specifications are applied to an airplane, the generalization may not apply because of changes in the configuration made during maintenance (e.g., maintenance, repair or overhaul) or earlier manufacturing changes. While the practical experience of the mechanic or technician may overcome the informational gap between the documentation and the actual configuration, such practical experience is often communicated inefficiently by word of mouth and documentation may be unavailable. Moreover, repair and maintenance may become more costly where the mechanic or technician needs to figure out the implications of departures from expected or wrongly documented configurations on an ad-hoc basis.
The operator or owner of the mechanical equipment may operate equipment with a sub-optimal configuration that does not comply with a desired technical specification because of a lack of adequate procedures for identification of the desired technical specification and tracking compliance with the desired technical specification. For example, a typical performance guarantee or warranty for an airplane, as the mechanical equipment, may cover the number of landings/takeoffs, engine hours, and general availability of flight readiness of the aircraft. However, an operator or an owner of an aircraft may fail to enforce the warranty or performance guarantee against the manufacturer because the lack of adequate record-keeping and monitoring of the actual performance of the aircraft that are necessary to demonstrate a performance deficiency. Thus, a need exists for a procedure that facilitates monitoring of compliance with a desired technical performance objective for the mechanical equipment.
In regulated industries, such as the airline industry, the noncompliance with a desired technical specification may represent a violation of a regulatory standard, which can subject the operator or owner of the mechanical equipment to economic penalties. Moreover, noncompliance with a configuration may pose a serious threat to the safety of passengers aboard a noncompliant aircraft. Thus, a need exists for facilitating compliance of a configuration of mechanical equipment with applicable safety requirements on a timely basis. | {
"pile_set_name": "USPTO Backgrounds"
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1. Technical Field
The present invention relates generally to a data compression and decompression and, more particularly, to systems and methods for providing content independent lossless data compression and decompression.
2. Description of the Related Art
Information may be represented in a variety of manners. Discrete information such as text and numbers are easily represented in digital data. This type of data representation is known as symbolic digital data. Symbolic digital data is thus an absolute representation of data such as a letter, figure, character, mark, machine code, or drawing,
Continuous information such as speech, music, audio, images and video, frequently exists in the natural world as analog information. As is well-known to those skilled in the art, recent advances in very large scale integration (VLSI) digital computer technology have enabled both discrete and analog information to be represented with digital data. Continuous information represented as digital data is often referred to as diffuse data. Diffuse digital data is thus a representation of data that is of low information density and is typically not easily recognizable to humans in its native form.
There are many advantages associated with digital data representation. For instance, digital data is more readily processed, stored, and transmitted due to its inherently high noise immunity. In addition, the inclusion of redundancy in digital data representation enables error detection and/or correction. Error detection and/or correction capabilities are dependent upon the amount and type of data redundancy, available error detection and correction processing, and extent of data corruption.
One outcome of digital data representation is the continuing need for increased capacity in data processing, storage, and transmittal. This is especially true for diffuse data where increases in fidelity and resolution create exponentially greater quantities of data. Data compression is widely used to reduce the amount of data required to process, transmit, or store a given quantity of information. In general, there are two types of data compression techniques that may be utilized either separately or jointly to encode/decode data: lossless and lossy data compression.
Lossy data compression techniques provide for an inexact representation of the original uncompressed data such that the decoded (or reconstructed) data differs from the original unencoded/uncompressed data. Lossy data compression is also known as irreversible or noisy compression. Entropy is defined as the quantity of information in a given set of data. Thus, one obvious advantage of lossy data compression is that the compression ratios can be larger than the entropy limit, all at the expense of information content. Many lossy data compression techniques seek to exploit various traits within the human senses to eliminate otherwise imperceptible data. For example, lossy data compression of visual imagery might seek to delete information content in excess of the display resolution or contrast ratio.
On the other hand, lossless data compression techniques provide an exact representation of the original uncompressed data. Simply stated, the decoded (or reconstructed) data is identical to the original unencoded/uncompressed data. Lossless data compression is also known as reversible or noiseless compression. Thus, lossless data compression has, as its current limit, a minimum representation defined by the entropy of a given data set.
There are various problems associated with the use of lossless compression techniques. One fundamental problem encountered with most lossless data compression techniques are their content sensitive behavior. This is often referred to as data dependency. Data dependency implies that the compression ratio achieved is highly contingent upon the content of the data being compressed. For example, database files often have large unused fields and high data redundancies, offering the opportunity to compress data at ratios of 5 to 1 or more. In contrast, concise software programs have little to no data redundancy and, typically, will not losslessly compress better than 2 to 1.
Another problem with lossless compression is that there are significant variations in the compression ratio obtained when using a single lossless data compression technique for data streams having different data content and data size. This process is known as natural variation.
A further problem is that negative compression may occur when certain data compression techniques act upon many types of highly compressed data. Highly compressed data appears random and many data compression techniques will substantially expand, not compress this type of data.
For a given application, there are many factors which govern the applicability of various data compression techniques. These factors include compression ratio, encoding and decoding processing requirements, encoding and decoding time delays, compatibility with existing standards, and implementation complexity and cost, along with the adaptability and robustness to variations in input data. A direct relationship exists in the current art between compression ratio and the amount and complexity of processing required. One of the limiting factors in most existing prior art lossless data compression techniques is the rate at which the encoding and decoding processes are performed. Hardware and software implementation tradeoffs are often dictated by encoder and decoder complexity along with cost.
Another problem associated with lossless compression methods is determining the optimal compression technique for a given set of input data and intended application. To combat this problem, there are many conventional content dependent techniques which may be utilized. For instance, filetype descriptors are typically appended to file names to describe the application programs that normally act upon the data contained within the file. In this manner data types, data structures, and formats within a given file may be ascertained. Fundamental problems with this content dependent technique are:
(1) the extremely large number of application programs, some of which do not possess published or documented file formats, data structures, or data type descriptors; PA1 (2) the ability for any data compression supplier or consortium to acquire, store, and access the vast amounts of data required to identify known file descriptors and associated data types, data structures, and formats; and PA1 (3) the rate at which new application programs are developed and the need to update file format data descriptions accordingly. PA1 (a) receiving as input a block of data from a stream of data, the data stream comprising one of at least one data block and a plurality of data blocks; PA1 (b) counting the size of the input data block; PA1 (c) encoding the input data block with a plurality of lossless encoders to provide a plurality of encoded data blocks; PA1 (d) counting the size of each of the encoded data blocks; PA1 (e) determining a lossless data compression ratio obtained for each of the encoders by taking the ratio of the size of the encoded data block output from the encoders to the size of the input data block; PA1 (f) comparing each of the determined compression ratios with an a priori user specified compression threshold; PA1 (g) selecting for output the input data block and appending a null data type compression descriptor to the input data block, if all of the encoder compression ratios fall below the a priori specified compression threshold; and PA1 (h) selecting for output the encoded data block having the highest compression ratio and appending a corresponding data type compression descriptor to the selected encoded data block, if at least one of the compression ratios exceed the a priori specified compression threshold.
An alternative technique that approaches the problem of selecting an appropriate lossless data compression technique is disclosed in U.S. Pat. No. 5,467,087 to Chu entitled "High Speed Lossless Data Compression System" ("Chu"). FIG. 1 illustrates an embodiment of this data compression and decompression technique. Data compression 1 comprises two phases, a data pre-compression phase 2 and a data compression phase 3. Data decompression 4 of a compressed input data stream is also comprised of two phases, a data type retrieval phase 5 and a data decompression phase 6. During the data compression process 1, the data pre-compressor 2 accepts an uncompressed data stream, identifies the data type of the input stream, and generates a data type identification signal. The data compressor 3 selects a data compression method from a preselected set of methods to compress the input data stream, with the intention of producing the best available compression ratio for that particular data type.
There are several problems associated with the Chu method. One such problem is the need to unambiguously identify various data types. While these might include such common data types as ASCII, binary, or unicode, there, in fact, exists a broad universe of data types that fall outside the three most common data types. Examples of these alternate data types include: signed and unsigned integers of various lengths, differing types and precision of floating point numbers, pointers, other forms of character text, and a multitude of user defined data types. Additionally, data types may be interspersed or partially compressed, making data type recognition difficult and/or impractical. Another problem is that given a known data type, or mix of data types within a specific set or subset of input data, it may be difficult and/or impractical to predict which data encoding technique yields the highest compression ratio.
Chu discloses an alternate embodiment wherein a data compression rate control signal is provided to adjust specific parameters of the selected encoding algorithm to adjust the compression time for compressing data. One problem with this technique is that the length of time to compress a given set of input data may be difficult or impractical to predict. Consequently, there is no guarantee that a given encoding algorithm or set of encoding algorithms will perform for all possible combinations of input data for a specific timing constraint. Another problem is that, by altering the parameters of the encoding process, it may be difficult and/or impractical to predict the resultant compression ratio.
Other conventional techniques have been implemented to address the aforementioned problems. For instance, U.S. Pat. No. 5,243,341 to Seroussi et al: describes a class of Lempel-Ziv lossless data compression algorithms that utilize a memory based dictionary of finite size to facilitate the compression and decompression of data. A second standby dictionary is included comprised of those encoded data entries that compress the greatest amount of input data. When the current dictionary fills up and is reset, the standby dictionary becomes the current dictionary, thereby maintaining a reasonable data compression ratio and freeing up memory for newly encoded data strings. Multiple dictionaries are employed within the same encoding technique to increase the lossless data compression ratio. This technique demonstrates the prior art of using multiple dictionaries within a single encoding process to aid in reducing the data dependency of a single encoding technique. One problem with this method is that it does not address the difficulties in dealing with a wide variety of data types.
U.S. Pat. No. 5,717,393 to Nakano, et al. teaches a plurality of code tables such as a high-usage code table and a low-usage code table in an entropy encoding unit. A block-sorted last character string from a block-sorting transforming unit is the move-to-front transforming unit is transformed into a move-to-front (MTF) code string. The entropy encoding unit switches the code tables at a discontinuous part of the MTF code string to perform entropy coding. This technique increases the compression rate without extending the block size. Nakano employs multiple code tables within a single entropy encoding unit to increase the lossless data compression ratio for a given block size, somewhat reducing the data dependency of the encoding algorithm. Again, the problem with this technique is that it does not address the difficulties in dealing with a wide variety of data types.
U.S. Pat. No. 5,809,176 to Yajima discloses a technique of dividing a native or uncompressed image data into a plurality of streams for subsequent encoding by a plurality of identically functioning arithmetic encoders. This method demonstrates the technique of employing multiple encoders to reduce the time of encoding for a single method of compression.
U.S. Pat. Nos. 5,583,500 and 5,471,206 to Allen, at al. disclose systems for parallel decompression of a data stream comprised of multiple code words. At least two code words are decoded simultaneously to enhance the decoding process. This technique demonstrates the prior art of utilizing multiple decoders to expedite the data decompression process.
U.S. Pat. No. 5,627,534 to Craft teaches a two-stage lossless compression process. A run length precompressed output is post processed by a Lempel-Ziv dictionary sliding window dictionary encoder that outputs a succession of fixed length data units. This yields a relatively high-speed compression technique that provides a good match between the capabilities and idiosyncrasies of the two encoding techniques. This technique demonstrates the prior art of employing sequential lossless encoders to increase the data compression ratio.
U.S. Pat. No. 5,799,110 to Israelsen, et al. discloses an adaptive threshold technique for achieving a constant bit rate on a hierarchical adaptive multistage vector quantization. A single compression technique is applied iteratively until the residual is reduced below a prespecified threshold. The threshold may be adapted to provide a constant bit rate output. If the nth stage is reached without the residual being less than the threshold, a smaller input vector is selected.
U.S. Pat. No. 5,819,215 to Dobson, et al. teaches a method of applying either lossy or lossless compression to achieve a desired subjective level of quality to the reconstructed signal. In certain embodiments this technique utilizes a combination of run-length and Huffman encoding to take advantage of other local and global statistics. The tradeoffs considered in the compression process are perceptible distortion errors versus a fixed bit rate output. | {
"pile_set_name": "USPTO Backgrounds"
} |
This application is a 371 of PCT/JP99/03381, filed Jun. 24, 1999.
The present invention relates to an RNA polymerase gene derived from hepatitis C virus (referred to as xe2x80x9cHCVxe2x80x9d herein), a method of screening using this gene or this RNA polymerase protein, and a substance able to be isolated by this screening method.
Generally known viral hepatitis includes hepatitis A which is mainly orally transmitted, and hepatitis B transmitted by means of the blood. Moreover, apart from these hepatitis, there is hepatitis called non-A, non-B hepatitis which is transmitted by means of blood transfusion. Since most of these infected with non-A, non-B hepatitis become chronic, and the incidence of development into cirrhosis and hepatoma is high, this is one disease for which the establishment of a certain means of treatment is urgently sought.
Through the causative agent of non-A, non-B hepatitis had been unclear for a long time, recently the causative virus was isolated by M. Houghton et al. (Japanese Patent Application Laid-Open (Kohyo) No. 2-500880), and was termed xe2x80x9cHCVxe2x80x9d. HCV is a single-stranded RNA virus belonging to the Flavivirdae, the length of its whole genomic RNA is about 9.4 kb. The genomic RNA is divided into 7 regions; core, E1, E2/NS1, NS2, NS3, NS4, and NS5; and the genes related to virus growth, etc. are primarily included in downstream regions from NS3.
HCV RNA polymerase is related to the transcription and replication of genomic RNA, and plays an important role in the reproduction of HCV. The gene encoding this polymerase is thought to be included in the above-mentioned NS5 region (Z. H. Yuan et al., Biochemical and Biophysical Research Communications 232, 231-235(1997), S. B. Hwang et al., Virology 227, 439-446(1997), S. E. Behrens et al., The EMBO Journal 15 12-22(1996)).
The Problem to Be Solved by the Invention
If the gene encoding HCV RNA polymerase can be isolated, it will become possible using this gene to easily screen for substances inhibiting RNA polymerase, and contribute greatly to the development of drugs for treating HCV. However, at present, although the nucleotide sequence of a portion of the NS5 region has been clarified (Japanese Patent Application Laid-Open (Kokai) No. 6-225770), the entire nucleotide sequence of the RNA polymerase gene has yet to be clarified.
The object of the present invention is to isolate the gene encoding the full length of HCV-derived RNA polymerase, to determine its nucleotide sequence, as well as to establish its expression system.
A further object of the present invention is to provide a screening method for a substance which inhibits the activity of this gene or this protein employing this gene or this RNA polymerase protein.
Means for Solving the Problem
In order to solve the above problem, the present inventors, as result of deliberate and focused research have succeeded in isolating the gene encoding the full-length of HCV-derived RNA polymerase, thereby completing the present invention.
That is to say, the present invention relates to the following (1) to (3).
(1) A gene encoding the following protein (a) or (b):
(a) a protein consisting of the amino acid sequence represented in SEQ ID NO:2;
(b) a protein consisting of an amino acid sequence derived from the amino acid sequence represented in SEQ ID NO:2 by deletion, substitution or addition of one or several amino acid(s), and which has RNA polymerase activity.
(2) A method of screening a substance which inhibits the activity of the gene of (1) above, or of the protein consisting of the amino acid sequence represented in SEQ ID NO: 2, wherein this method comprises the following steps:
(a) a step of contacting the gene of (1) above or the protein consisting of the amino acid sequence represented in SEQ ID NO: 2, or a fragment of this protein, with a test sample; and,
(b) a step of selecting a substance which inhibits the activity of the gene of (1) above, or of the protein or the partial peptide fraction consisting of the amino acid sequence represented in SEQ ID NO: 2.
(3) A substance able to be isolated by the method of (2) above, wherein this substance inhibits the activity of the gene of (1) above or of the protein consisting of the amino acid sequence represented in SEQ ID NO: 2.
The descriptions contained in the specification of Japanese Patent Application No. 10-177817, which forms the basis of the right of priority of the present application, are incorporated herein in their entirety.
Below, the present invention will be explained in detail.
The gene of the present invention encodes (a) a protein consisting of the amino acid sequence represented in SEQ ID NO: 2; or, (b) a protein consisting of an amino acid sequence derived from the amino acid sequence represented in SEQ ID NO:2 by deletion, substitution, or addition of one or several amino acid(s) and having RNA polymerase activity.
The deletion, etc. of one or several amino acid can be performed by techniques in common use at the time of filing this application, such as, for example, site-specific mutagenesis (Nucleic Acids Res. 10, 6487-6500, 1982).
The gene of the present invention is able to be obtained from the blood of non-A, non-B hepatitis patients as described in the examples, or from the strain of E. coli into which a vector (pCALN/HCV RBZ) comprising the gene of the present invention was introduced, has been deposited at the National Institute of Bioscience and Human-Technology, Agency of Industrial Science and Technology (1-1-3, Higashi, Tsukuba-shi, Ibaraki-ken, Japan) (Accession No. FERM BP-6763) on Oct. 31, 1997).
Further, the present invention relates to a screening method for a substance which inhibits the activity of this gene or this protein, employing the gene of the present invention or an RNA polymerase protein consisting of the amino acid sequence represented in SEQ ID NO: 2; and, to a substance able to be isolated by this screening method employing this gene or this RNA polymerase protein.
The RNA polymerase encoded by the gene of the present invention is an enzyme involved in the transcription and replication of HCV genomic RNA. Therefore, a substance which inhibits this enzyme is thought to be able to prevent the reproduction of HCV, and is promising as a drug for treating non-A, non-B hepatitis. By using the gene of the present invention it will be possible to produce HCV-derived RNA polymerase easily and in great quantities, and as a result of this, the screening of inhibitory substances for the RNA polymerase will become simpler.
The protein of the present invention that can be used for screening can be either a recombinant type, a wild type, or a partial peptide. Further it can be a purified peptide or a partial peptide thereof.
One embodiment of this method of screening comprises the steps of (a) contacting the gene of the present invention or the protein consisting of the amino acid sequence represented by SEQ ID NO: 2, or a fragment of this protein, with a test sample; and, (b) selected a substance which inhibits the activity of the gene of the present invention or the protein consisting of the amino acid sequence represented by SEQ ID NO: 2. There is no particular limitation on what can be used as a test material in this screening method but for example, a cell extract, a cell culture supernatant, a protein, a peptide, or synthetic low molecular weight compound can be used. | {
"pile_set_name": "USPTO Backgrounds"
} |
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