Planographic printing means printing from a flat surface, as opposed to a raised surface (as with relief printing) or incised surface (as with
intaglio printing). The process utilizes the property that water will not mix with oil. The process produces a
lithograph or
offset lithograph by applying a rusche (greasy substance) to a metallic plate or stone. (The origin of the term lithography includes reference to litho, for stone.)
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