Weather-stable titanium dioxide pigment and method for the production thereof <http://v3.espacenet.com/publicationDetails/biblio?adjacent=true&KC=A&date=20071227&NR=200609340A&DB=EPODOC&locale=en_EP&CC=ZA&FT=D>

摘要

Тhе invention relates to a weather-stable titanium dioxide pigment, which has good optical properties and a dense silicon dioxide skin doped with metal atoms. Particularly suitable doping elements are tin, zirconium and titanium. The dense silicon dioxide skin consists of a number of layers, the innermost of which not containing a significant quantity of metal atoms. The inventive coating is produced by adding the constituents in succession into the alkaline suspension (pH value of at least 9) during which the pH value decreases. In order to completely form the doped dense SiOskin, it is necessary со slowly decrease the pH value until reaching a value less than 9. The pigment is particularly suited for use in paints, varnishes and plastics.