Silica-cerium oxide composite particles, method for the preparation thereof and resin composition and a cosmetic composition compounded therewith

摘要

Proposed is a powder of silica-cerium oxide composite particles useful as an ultraviolet shielding agent in a resin composition or as a sunscreening agent in a cosmetic composition. The cerium oxide-based composite particles consist of cerium oxide and 5 to 60% by weight of amorphous silica calculated as SiO2. The composite particles are prepared by the addition of sodium silicate and an inorganic acid to an aqueous slurry containing precipitates of cerium hydroxide so as to precipitate amorphous silica on the particles of cerium hydroxide followed by drying and calcination of the particles separated from the reaction mixture. Various formulations of cosmetic compositions compounded with the silica-cerium oxide composite particles are disclosed.