PROCESS FOR PRODUCING HEAT-EXPANDABLE MICROPARTICLES HAVING FINE GRAINS ADHERING TO THE SURFACE, PROCESS FOR PRODUCING HEAT-EXPANDABLE MICROPARTICLES HAVING FINE GRAINS OF ORGANIC RESIN ADHERING TO THE SURFACE, HEAT-EXPANDABLE MICROPARTICLES OBTAINED BY THESE PRODUCTION PROCESSES, EXPANDE

摘要

In a suspension containing a low-boiling point organic solvent, a polymerizable monomer and a polymerization catalyst, heat-expandable microcapsules, which are not dissolved in the components of the suspension and obtained by suspension-polymerization of the polymerizable monomer as described above, are uniformly surface-coated with inorganic fine grains or fine grains made of an organic resin so that there arises little fear of the aggregation of the microcapsules with each other or the heat-fusion of expanded microcapsules. Using the heat-expandable microparticles thus obtained as foaming particles, a foamed wallpaper having the foaming particles uniformly distributed therein and thus showing a stable foamed state can be obtained.