METHOD FOR MAKING PLANOGRAPHIC PRINTING PLATE

摘要

PROBLEM TO BE SOLVED: To provide a method for making a positive or negative planographic printing plate having high hydrophilicity in a hydrophilic layer, excellent bonding power of the layer to the support and improved printing stain resistance and giving printed matter free of stain even under severe printing conditions. SOLUTION: An original plate for a planographic printing plate having a hydrophilic layer comprising a high molecular compound bonded directly chemically to the surface of the support and has a hydrophilic functional group and an image forming layer in order on the support is imagewise exposed and then developed with a developing solution containing an alkali metallic silicate as a principal component.