Dendrite or asteroidal titanium dioxide micro-particles

Abstract

Dendrite or asteroidal titanium dioxide micro-particles having a length of 0.2 to 0.5 .mu.m, a thickness of 0.05 to 0.1 .mu.m, and a specific surface area of 20 to 130 m.sup.2 /gram, are produced by treating hydrated titanium oxide particles with an alkali, mixing instantaneously the resulting reaction product with an amount of hydrochloric acid in a ratio of 1 to 4 mols of hydrochloric acid to one mol of the titanium oxide in the reaction product to effect a reaction, then aging under heat at 85.degree. C. or higher, and then drying or, if necessary, firing after the drying, and subsequently may be coated with at least one from oxides and hydrated oxides of elements selected from aluminum, silicon, titanium, zirconium, tin and antimony to improve the dispersibility and resistance to light of the particles, or may be coated with tin oxide containing antimony or indium oxide containing tin to make the particles electroconductive. These titanium dioxide micro-particles are useful for use in electroconductive paints, electroconductive resin compositions, paints and electroconductive paints for magnetic recording media, sunscreen cosmetics, UV screening paints and UV shielding plastic compositions and the like.

Dependencies are inferred from the claim text.