Core-shell type zinc oxide microparticle or dispersion containing the microparticle, and production process and use of the microparticle or the dispersion

Abstract

Disclosed herein are core-shell type zinc oxide microparticles, a dispersion containing such microparticles, and a production process and uses of the microparticles and the dispersion. As disclosed herein, the core-shell type zinc oxide microparticles have an average particle diameter of from 50 to 1,000 nm. The core is a secondary particle of spherical shape to the surface of which a polymer is attached as a shell. Methods for making the microparticles include the steps of: mixing together a zinc salt and a polymer in an organic solvent so as to obtain a mixture; and heating/refluxing the mixture at a predetermined temperature so as to cause core-shell type zinc oxide microparticles to precipitate, wherein the zinc salt is zinc acetate; and uses such as cosmetics, resins and fibers which contain the core-shell type zinc oxide microparticles and have an ultraviolet light blocking action.