IRREGULAR-SHAPED MICROPARTICLES, PROCESS FOR PRODUCTION OF IRREGULAR-SHAPED MICROPARTICLES, AND COSMETICS AND RESIN COMPOSITIONS CONTAINING IRREGULAR-SHAPED MICROPARTICLES

摘要

Non-spherical fine particles capable of responding to highly advanced requirements of recent years, including further improvements in optical characteristics such as total light transmittance and optical diffusible property related to resin molded products and further improvements in feeling, soft focus, coverage and durability related to cosmetic products, as well as methods of their production and their use are provided. These non-spherical fine particles each have a polyhedral general shape with six or more surfaces each of which is formed as a concave surface, satisfying all of the conditions that the average value of the maximum external diameters L 1 of the non-spherical fine particles is in the range of 0.1 - 20µm, that the ratios between the minimum external diameters L 2 and the maximum external diameters L 1 of the individual non-spherical fine particles have an average value in the range of 0.60 - 0.97, and that they have an average number per particle of 6 - 14 concave surfaces of which the ratio of the maximum diameter m 1 with respect to the maximum external diameter L 1 is in the range of 0.20 - 0.90,