摘要 |
PROBLEM TO BE SOLVED: To provide a method for efficiently producing a heteromorphic polymer fine particle having a shape other than spheric or nearly spheric one, and to provide the heteromorphic polymer fine particle having a uniform shape. SOLUTION: This method comprises adding a surface monomer, an auxiliary solvent, polymerization initiator and a dispersant to a dispersion liquid containing seed polymer particles dispersed in a medium, polymerizing the surface monomer by a seed dispersion polymerization method and removing the auxiliary solvent. The auxiliary solvent is an organic solvent which is a poor solvent or a non-solvent for the seed polymer, but a good solvent for the surface polymer and partially soluble in the medium. The medium is a mixed liquid consisting of 20 to 60 wt.% (i) a poor solvent (PS) for the auxiliary solvent, (ii) a mixed liquid of 80 wt.% or more PS and 20 wt.% or less non- solvent (NS) for the auxiliary solvent, or (iii) a mixed liquid of 20 to 60 wt.% a good solvent (GS) for the auxiliary solvent and 80 to 40 wt.% NS. The auxiliary solvent is added in an amount of 50 to 500 wt.% of the seed polymer. COPYRIGHT: (C)2003,JPO
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