| 摘要 |
The compsn. comprises (A) a photopolymerisable, ethylenically unsatd. monofunctional, water-soluble monomer opt. with an ethylenically unsatd. polyfunctional monomer; (B) a water soluble polyvinyl acetate contg. both acetyl and OH gps., having a polymerisation degree of 300-2000 and a saponification degree of 65-99 moles %, (C) a photopolymerisation promoter activatable by actinic light and (D) an activator comprising a phosphine deriv. of formula P (X)(Y)(Z) where X, Y and Z are H, halogen, alkyl, alkoxy, aryl, vinyl or allyl, at most one of X, Y and Z being H and pref. one being aryl. Unlike previous prods. the above does not require prelimination or bump exposure. The exposed prod. is developed by simply washing with water to remove the unexposed zones. Used for prodn. of printing plates. |
