PURPOSE: To form a dense membrane by using an anionic water-soluble high polymer obtained by copolymerizing ≥3 kinds of monomers selected from (A) acrylic acid, (B) acrylonitrile, (C) acrylamide alkylsulfonic acid in an aq. system.
CONSTITUTION: A polymer or the salt thereof obtained by copolymerizing ≥3 kinds of acrylic monomers among (A) acrylic acid, (B) acrylonitrile, and (C) ≥1 kind selected from acrylamide alkylsulfonic acid is used as said anionic water- soluble high polymer substance in the manufacture of the microcapsule, whose wall membrane consists essentially of a polycondensation product of melamine and formaldehyde, in an aq. acidic medium contg. the anionic water-soluble high polymer substance. In this way, the microcapsule having a high solid content, low viscosity, a dense microcapsule wall, and a collectively excellent quality can be manufactured with In-Situ polymerization.
HASEGAWA KIYOHARU
TAMURA YUKIO
OONO YOSHIHIRO
