POST-TREATED TITANIUM DIOXIDE AND PROCESS FOR PRODUCING SAME

摘要

TITLE: POST-TREATED TITANIUM DIOXIDE AND PROCESS FOR PRODUCING SAME ___ _ This invention concerns a new product consisting of TiO2 particles having pigmentary granulometric and, morphological characteristics. It includes a chemically reactive coating consisting of a mixture of oxides and oxychlorides selected from the group consisting of A12O3 and AlOCl; SiO2 and SiOC12; and ZrO2 and zrOC12. The particles of reactive TiO2 product are preparedas follows: the surface Gf the Tio2 particles is activated by thermally treating the particles in a moving bed with an anhydrc,us gas at 400.degree.-600.degree.C. The particles are then made to react in a moving bed at 350.degree.C to 600.degree.C, in the presence of a carrier gas, with an i.norganic chloride selected from the group consisting of AlCl3, SiC14 and ZrC14. This new product is useful, for instance, in TiO2 pigments coated with organic molecules which provide an affinity for the vehicles of paints.