| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for reducing the chemical activity and photo activity of titanium dioxide nanoparticles. SOLUTION: The method comprises a step of adding a densifying agent, such as citric acid, to aqueous slurry of the titanium dioxide nanoparticles and a step of treating the aqueous slurry with a source of alumina, such as a solution of sodium aluminate, to form alumina-treated titanium dioxide nanoparticles. In one embodiment the particles are treated with a source of silica, such as a solution of sodium silicate. The nanoparticles can be treated with a source of silica and a source of alumina. The treated nanoparticles can be silanized. The titanium dioxide nanoparticles described herein are useful in cosmetic, coating and thermoplastic compositions. COPYRIGHT: (C)2005,JPO&NCIPI |
