A process for producing thermo-expansive microcapsules wherein a polymerizing
mixture
containing ethylenic unsaturated monomer and a blowing agent is suspend-polymerized
to microencapsulate the blowing agent with the resultant polymer. The above-mentioned
suspension-polymerization is performed with the presence of at least one compound
selected from the group consisting of polypeptides and derivatives thereof as a
suspension stabilizer. The process can control the particle size of microcapsules
easily, attain stable reaction system and produce thermo-expansive microcapsules
that disperse well in medium such as paint or inks.
