Patent ID: 6113682
Filing Date: 2000-09-05
Classification: A61K,A61Q,C01P,C09C

Abstract:
A method of preparing composite pigments for make-up cosmetics, comprising the steps of:(1) reacting a sodium silicate solution with an aqueous sulfuric acid solution to form a silica gel slurry;(2) crushing said silica gel slurry to form coarse silica;(3) grinding said coarse silica by means of an impact mill followed by fine grinding with an air current impact system of an air jet mill to form flaky silica;(4) coating said flaky silica with ultrafine titanium dioxide to form composite particles by admixing said flaky silica (3) with 0.2.about.0.3 mol/l of urea, 0.3.about.0.4 mol/l of sulfuric acid and 0.007.about.0.015 mol/l of titanyl sulphate in distilled water, then heating, washing and drying, and then baking; and(5) coating the resultant baked composite particles with silicon polymer to give said composite pigments.