PURPOSE: To improve adhesive properties with a base material and repeelability by mixing an aqueaus dispersion contg. a specified copolymer particle and a self-emulsifying polyfunctional isocyanate soln.
CONSTITUTION: 0.5-10 wt.% hydroxyl group-contg. monomer (e.g. 2- hydroxymethyl acrylate) and/or α,β-unsatd. carboxylic acid monomer (e.g. acrylic acid) and 99.5-90 wt.% other copolymerizable monomer (e.g. methyl methacrylate) are emulsion-copolymerized to obtain an aqueaus dispersion (A) contg. 40-65 wt.% copolymer particle with a glass transition temp. of -35°C or lower, a gel fraction of 15-50 % and a wt. swelling ratio of 10-50. 100 pts.wt. polyfunctional isocyanate compd. contg. two or more isocyanate groups (e.g. hexamethylene diisocyanate), 20-300 pts.wt. hardly water-soluble org. solvent with no reactivity with this isocyanate group (e.g. toluene) and 3-15 wt.% surface active agent are mixed to obtain a self-emulsifying polyfunction isocyanate soln. (B). Then, the component A and the component B are mixed in such a way that the isocyanate content in the whole solid component is 0.3-1.5 wt.%.
KIMURA TERUO
TSURUGATANI MUNEAKI
