PHOTOSENSITIVE LITHOGRAPHIC PLATE REQUIRING NO DAMPENING WATER

摘要

PURPOSE:To form a uniform coating layer and to enable easy handling of a lithographic plate before development and to shorten development processing time by forming a coating layer composed essentially of a polymer soluble in water or a developing soln. on the silicone rubber layer of the photosensitive lithographic plate using an upper silicone rubber layer and requiring no dampening water type. CONSTITUTION:A lower alcohol soln. of 3-10wt% concn. polymer is prepared by dissolving a homopolymer or copolymer of PVA or polyvinyl ether in said 1-5C lower alcohol. The silicone rubber layer of the photosensitive lithographic plate using the upper silicone rubber layer and requiring no dampening water type is coated with the lower alcohol soln. of said polymer by using a slit die or the like, and dried to form a coating layer of 0.5-100mum dry film thickness to form the final product of the coated photosensitive lithographic plate of said type. This method permits easy handling of the plate before development and damage of the silicone rubber layer to be prevented.