| 摘要 |
PURPOSE:To obtain a novel coating pigment having high whiteness and resistant to darkening of the color even in a state wet with oily substance or water, by dispersing flaky inorganic powder in an aqueous solution of a water-soluble titanium salt, water-soluble aluminum salt and urea, subjecting the dispersion to a specific treatment and calcining the product. CONSTITUTION:A flaky inorganic powder (preferably mica, sericite, talc or kaolin) in dispersed in an aqueous solution containing a water soluble titanium salt, a water-soluble aluminum salt and urea. The dispersion is heated at 80-100 deg.C under agitation to effect the reaction of decomposed and produced ammonia to the above titanium salt and aluminum salt. The produced titanium oxide hydrate and aluminum oxide hydrate are successively deposited on the surface of the particles of the flaky inorganic powder to form layers. The inorganic powder is separated from the dispersion by filtration, washed with water, dried and calcined to obtain the objective pigment composed of said inorganic powder particle coated with titanium oxide and then with aluminum oxide.
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