| 摘要 |
PROBLEM TO BE SOLVED: To provide a black pearlescent pigment free from the defects of a conventional platy or flaky iron oxide pigment and to provide use thereof. SOLUTION: Iron oxyhydroxide is dispersed in water or an alkaline aqueous solution containing e.g., sodium hydroxide, potassium hydroxide, or sodium aluminate, and the aqueous dispersion is hydrothermally treated at 150-300°C in a pressure vessel to obtain a scaly iron oxide particles having hematite structure, which is then heated at 350-600°C in a reducing atmosphere. Thus, scaly magnetite-structure iron oxide particles having an average length of 5-30 μm in the direction of the plate surface and having an average length of 0.05-0.5 μm in the thickness direction can be formed. COPYRIGHT: (C)2010,JPO&INPIT |
