Photosensitive resin composition and process for producing the same.

摘要

Disclosed are a photosensitive resin composition essentially comprising (A-1) 100 parts by weight of modified polyvinyl alcohol comprising a structural units of formulae (I), (II) and (III): wherein R represents a hydrocarbon group having 1 to 20 carbon atoms; X represents an aliphatic, alicyclic or aromatic divalent hydrocarbon group having 1 to 20 carbon atoms or a divalent group having at least one carboxyl group in the molecule thereof, the proportion of the structural unit of formula (I) being from 1 to 40 mol%, the total proportion of the structural units of formulae (II) and (III) being from 60 to 99 mol%, and the carboxyl equivalent attributed to the structural unit of formula (III) being from 0.3 to 5 mol/kg, (B) from 0.1 to 10 parts by weight of an unsaturated epoxy compound, (C) from 20 to 200 parts by weight of a polymerizable unsaturated compound having an ethylenical double bond in the molecule thereof, and (D) from 0.1 to 10 parts by weight of a photopolymerization initiator; a photosensitive resin composition containing (A-2) modified polyvinyl alcohol obtained by reacting partially saponified polyvinyl alcohol having a degree of saponification of 60 to 99 mol% and a number average degree of polymerization of 300 to 2,000 with a carboxylic acid anhydride in a molten state; and a process for producing a photopolymerizable resin composition comprising reacting partially saponified polyvinyl alcohol having a degree of saponification of 60 to 99 mol% and a number average degree of polymerization of 300 to 2,000 with a carboxylic acid anhydride in a molten state to prepare (A-2) modified polyvinyl alcohol and mixing modified polyvinyl alcohol (A-2) with (C) a polymerizable unsaturated compound having an ethylenical double bond in the molecule thereof, and (D) a photopolymerization initiator. The photosensitive resin compositions provide a printing plate material having high sensitivity and highly precise image reproducibility, from which material is obtained a printing plate whose relief has excellent toughness. The use of the modified polyvinyl alcohol obtained by a molten reaction makes it easy to prepare a solution of a photosensitive resin composition.