Process for obtaining smooth and tack-free surfaces on relief printing plates for flexography, obtained by photopolymerization

摘要

Non-tacky, smooth, structureless surfaces of photopolymer relief printing plates for flexographic printing, whose relief layers are prepared in a conventional manner by exposing the photopolymerizable relief-forming layers of flexographic printing plates imagewise to actinic light and washing out the unpolymerized, unexposed areas with a suitable solvent, are produced by a process in which the flexographic printing plates are after-treated with a liquid medium which contains elemental bromine or is capable of forming elemental bromine, and then washed with a neutralization bath, one or more paraffinsulfonates, fatty alcohol ethersulfates or alkyl phosphates or a cationic or anionic surfactant possessing one or more perfluorinated carbon chains being employed in the bromine-containing, liquid medium. The relief printing plates obtained according to the invention are used for flexographic printing.