Mit Polysiloxanharz beschichtete Siloxankautschukpartikel

摘要

A powder of silicone rubber having improved flowability and dispersibility consists of particles of a cured silicone rubber of which each particle has a coating layer of a polyorganosilsesquioxane resin in a specified coating amount. The powder is prepared by the admixture of an aqueous dispersion of a cured silicone rubber particles, which is preferably prepared by the hydrosilation reaction between a vinyl group-containing organopolysiloxane and an organohydrogen polysiloxane emulsified in an aqueous medium, with a trialkoxy silane compound such as methyl trimethoxy silane together with an alkaline compound, e.g., ammonia water, under agitation so that the hydrolysis-condensation reaction of the trialkoxy silane compound proceeds to form a coating layer on the surface of the silicone rubber particles.