| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a pearl pigment which is excellent in gloss and interference power, has high refractive index and surface smoothness, and exhibits a high interference color effect by forming a metal oxide coating layer mainly comprising titanium oxide and contg. Ca and Mg on the surface of a flaky substrate and to obtain a process for producing the same. SOLUTION: This pigment comprises a flaky substrate coated with a metal oxide layer. The oxide layer has a high refractive index, contains Ca and Mg at least partly in the form of a titanate, and has a low porosity due to the effect of Ca and Mg compds. as sintering assistants. The flaky substrate is pref. selected from among natural muscovite and sericite, flaky synthetic mica, glass flakes, etc., and has a size of 200μm or lower and an average thickness of 1μm or lower. The substrate is suspended in water, and the suspension is heated to 70-80 deg.C, mixed with a Ca salt and an Mg salt, and dropped together with sodium hydroxide into an aq. mixed soln. contg. Ti ions at a pH of 1.5-2.5. The resultant solid is filtered and baked.</p> |
