The composition of polymeric elastomerico photo sensitive printing plates for the production of flexograficas processaveis in basic solutions or semi aqueous solvent systems.

摘要

A high molecular weight butadiene/acrylonitrile copolymer is used in a photosensitive composition containing the following: (A) 40 to 90% by weight of the total composition of a high molecular weight butadiene/acrylonitrile carboxylated copolymer having a number average molecular weight of 30,000 to 125,000, an acrylonitrile content of 10 to 50%, and a carboxyl content of 1% to 15% by weight. (B) 5 to 60% by weight of the total composition of a high molecular weight butadiene/acrylonitrile noncarboxylated copolymer having a number average molecular weight of 50,000 to 100,000, an acrylonitrile content of 10 to 30% so that the combination of the carboxylated and non carboxylated high molecular weight copolymers give a composition with a carboxyl content of 3 to 10%. (C) 2 to 40% by weight of the total composition of an addition photopolymerizable ethylenically unsaturated monomer and (D) 0.1 to 10% by weight of the total composition of a photoinitiator activatable by actinic radiation. A photosensitive flexographic plate comprises the above composition layered on a supporting substrate.