| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a pigment which, like natural pearl, has a silky delicate luster (silkiness) by coating with a metal oxide synthetic fluorophlogopite particles having a specified mean particle diameter, a specified particle diameter standard deviation, and a specified particle thickness in laser diffraction particle size distribution measurement. SOLUTION: The synthetic fluorophlogopite particles have a mean particle diameter of 3-10μm, a particle diameter standard deviation of 1.70 or below, and a particle thickness of below 0.2μm. The mica as the starting material can be obtained by a melt synthesis process, namely, a process comprising mixing silicon oxide with aluminum oxide, magnesium oxide, a silicofluoride, and a fluoride, melting the mixture by heating to about 1,500 deg.C, and crystallizing the melt by cooling. Particles having the specified shape can be obtained by finely powdering the easily peelable synthetic mica crystal lumps. The metal oxide is exemplified by an oxide of titanium, zirconium, iron, chromium, or vanadium, desirably, rutile titanium dioxide.</p> |
