Water-soluble composition admixture of copolymer having ethylenic unsaturation in side chain and anthraquinone photosensitizer

Claim 1

A water-soluble, photosensitive resin composition comprising a mixture of (a) a water-soluble unsaturated copolymer having an ethylenic unsaturated bond in the side chain obtained by reacting a prepolymer which is formed by addition polymerization of 40-95 mol% of an unsaturated amide compound, 5-10 mol% of an unsaturated carboxylic acid or salts thereof and each 0-30 mol% of at least one vinyl monomer which is co-polymerizable with the unsaturated amide and unsaturated carboxylic acid or salts thereof selected from the group consisting of vinyl acetate, vinyl propionate, styrene and alkyl-, hydroxyalkyl- or aminoalkylesters of unsaturated carboxylic acid, with an ethylenic unsaturated compound having an oxirane ring under heating in the presence of a polymerization inhibitor, and (b) a water soluble anthraquinone sulfonic acid, anthraquinone carboxylic acid or salts thereof as photosensitizer, the amount of the ingredient (b) being 0.5 - 20% with respect to the weight of the ingredient a).