PRODUCTION OF RESIN BINDER FOR WATER-BASED FLEXOGRAPHIC INK

摘要

PURPOSE:To produce the titled binder excellent in dryability, film gloss, pigment dispersion etc., by emulsion-polymerizing an ethylenically unsaturated monomer in the presence of a specified protective colloid. CONSTITUTION:A copolymer comprising 30-60mol% styrene, 20-60mol% maleic monoester (e.g., monoethyl maleate), or 20mol% (meth)acrylate [e.g., methyl (meth)acrylate] and 0-20mol% maleic acid and having an acid value of 50-300 is neutralized to a degree of neutralization of the carboxyl groups of the copolymer of 7-100% to obtain a protective colloid comprising a water- soluble salt of the copolymer. 10-1,000pts.wt. ethylenically unsaturated monomer comprising 10-100wt% styrene, 0-50wt% nitrogen-containing ethylenically unsaturated monomer and 0-50wt% other ethylenically unsaturated nomoner is emulsion-polymerized at 20-95 deg.C in the presence of 100pts.wt. (in terms of solid matter) above protective colloid.