RADIATION-SENSITIVE MIXTURE AND RECORDING MATERIAL BASED ON OLIGOMERIC MALEATES AND FUMARATES

摘要

A radiation-sensitive mixture is disclosed which contains as essential constituents a) at least one thermoplastic, elastomeric block copolymer of the formulae (A-B)m-A, (B-A)m+l-B, (A-B)m+l or (A-B)oY, in which A is a thermoplastic, nonelastomeric polymer block having a glass transition temperature of 25.degree.C or above and B is an elastomeric polymer block having a glass transition temperature of 10.degree.C or below, Y is Sn or Si, m is an integer from 1 to 10, and o is 2 if X is Sn, or 4 if X is Si, b) at least one ethylenically polyunsaturated compound, and c) a photopolymerization initiator, wherein at least one of the ethylenically polyunsaturated compounds corresponds to the formula I R-(O-?-CH=CH-?-O-X)n-O-?-CH=CH-?-O-R (I) where R is a straight-chain or branched alkyl radical, X is a straight-chain alkylene br cycloalkylene, it being possible for individual methylene groups to be substituted by -O-, -S-, carbonyl or carbonyloxy groups, and n is 1 to 5. The mixture can be used to produce relief and flexographic printing plates having a high Shore A hardness. The recording layers on which the printing plates are based are stable on storage and exhibit a high photosensitivity.