| 摘要 |
PURPOSE:To obtain titanium dioxide coated iron oxide pigment having excellent light resistance and weather resistance, by coating the surface of flaky mica-like iron oxide crystal particles with rutile titanium dioxide. CONSTITUTION:A titanium compound solution is added to an aqueous dispersion of flaky mica-like iron oxide crystal particles. In any process before calcination, a rutile transition promoter (e.g. zinc salt or tin salt) is added to the dispersion, fine particles of hydrous titanium dioxide formed by hydrolysis of the titanium compound are deposited on the iron oxide crystal particles, which are filtered, washed and dried to give the aimed pigment wherein substantially most of the coating layer of titanium oxide is changed to rutile type in calcination.
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