PHOTOSENSITIVE MIXTURE, PHOTOSENSITIVE PRINTING PLATE AND FLEXOGAPHIC PRINTING PLATE

摘要

PROBLEM TO BE SOLVED: To obtain a photosensitive mixture, a photosensitive printing plate and a flexographic printing plate having improved durability to UV-curing printing ink. SOLUTION: This photosensitive mixture is a mixture contg. at least on of elastomer type binder, at least one of photopolymerizable ethylenic unsatd. compd. and at least one of photoinitiator or photoinitiator system and contains 10-45wt.% at least one of thermoplastic elastomer type block copolymer contg. two or more kinds of polymer blocks each consisting of arom. vinyl units and one or more kind of polymer blocks each consisting of isoprene and/or isoprene- butadiene units. The block copolymer contains <=70% vinyl bonds and has <=20 deg.C a glass transition temp. and <=30 deg.C a peak temp. in primary dispersion of tanδ.