Self-adhesive materials coated with crosslinked acrylic! polymers - contg. copolymerised benzoin (meth)acrylate! as photoinitiator

摘要

Self-adhesive materials coated with a polyacrylic acid deriv. contg. a copolymerised photo-initiator, and crosslinked by brief UV irradiation, are made using 0.01-5(0.1-2) wt. % benzoin (meth)acrylate as photo-initiator. Used esp. for prodn. of self-adhesive tapes. The photoinitiators are readily obtained in yield of aound 90% pure cpd. by reaction of benzoin with (meth)acryloyl chloride in CH2Cl2 in presence of triethylamine. This compares with 60% yields of more complex (meth)acrylate esters used for this purpose, which require a multi-stage synthesis. Amounts up to 5% are readily copolymerised and the copolymers are lighter in colour. Thermal stability is excellent.