This printing technique uses a planographic process in which prints are pulled on a special press from a flat stone or metal surface. The surface has been chemically sensitised so that ink sticks only to the design areas, and is repelled by the non-image areas. Lithography was invented in Germany in 1798. In modern lithography, the image is made of a polymer coating applied to a flexible aluminum plate. The image can be printed directly from the plate (the orientation of the image is reversed), or it can be offset, by transferring the image onto a flexible sheet (rubber) for printing and publication (Wikipedia).
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