PURPOSE: To manufacture a direct picture type planographic original plate excellent in hydrophilic property and water resistance and stable in quality, by using an alkali metal salt of polyhydroxyacrylic acid and a polyamine-polyamide-epichlorohydrin adduct in producing a picture-receiving layer.
CONSTITUTION: To 1pts.wt. of an alkali metal salt of polyhydroxyacrylic acid of the formula (wherein R is H, 1W4C alkyl; M is H, an alkali metal; n is an integer), is added a polyamine-polyamide-epichlorohydrin adduct in an amount of preferably 0.1W0.5pts.wt. A dispersed liquid prepared by adding an inorganic pigment or the like to the mixture is coated on a water-resistant base and is brought into a cross-linking reaction to form the picture-receiving layer, thereby producing the original plate for printing. As the inorganic pigment, for example, a clay, zinc oxide or the like is used in an amount of preferably 0.1W5pts.wt. per 1pts.wt. of the mixture.
WATANABE TOMOKO