Three dimensions the minute resin grain and its manufacturing method null which build a bridge

摘要

Polymer microparticles having a three-dimensional network structure and an average particle size of 0.0l to l micron are obtained by emulsion polymerization of ethylenically unsaturated monomeric composition containing (a) at least one polyfunctional monomer having a plurality of polymerizable sites, or (b) a combination of two ethylenically unsaturated monomers each bearing mutually reactive functional groups in an aqueous medium in the presence of a compound or resin having a betaine group. The betaine compound or resin is incorporated into the polymer microparticles by physically adhering or covalently binding thereto to enhance the dispersing stability of the microparticles over a wide range of pH.