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README.md

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 # Dataset Card for "USPTO-30K"
 
+Existing benchmarks for Optical Chemical Structure Recognition have some limitations. 
+Being created using only a few documents, they contain batches of very similar molecules. For example in a patent, a molecule could typically be displayed together with all the substituent of one particular substructure, resulting in large batches of almost identical molecules. 
+Additionally, the existing sets contain molecules of different kinds, including superatom groups and various markush features, which should be evaluated independently.
+In practice, it is important to delimit on which types of molecules models can be applied.
+
+We introduce USPTO-30K, a large-scale benchmark dataset of annotated molecule images, which overcomes these limitations. 
+It is created using the pairs of images and MolFiles by the United States Patent and Trademark Office. 
+Each molecule was independently selected among all the available documents from 2001 to 2020. 
+The set consists of three subsets to decouple the study of clean molecules, molecules with abbreviations and large molecules. 
+
+- USPTO-10K contains 10,000 clean molecules, i.e. without any abbreviated groups.
+- USPTO-10K-abb contains 10,000 molecules with superatom groups. 
+- USPTO-10K-L contains 10,000 clean molecules with more than 70 atoms. 
+
 [More Information needed](https://github.com/huggingface/datasets/blob/main/CONTRIBUTING.md#how-to-contribute-to-the-dataset-cards)