| 摘要 |
PURPOSE:To prepare cosmetics, esp. makeup, having improved adhesivity to the skin, easily, by compounding an yellow iron oxide pigment having improved crystal form, particle size distribution and particle morphorogy, obtained by hydrothermal reaction. CONSTITUTION:Yellow iron oxide prepared from ferric sulfate by wet process, is dispersed in 0-10N (pref. 0-3N) alkaline solution, and subjected to the hydrothermal reaction at 100-250 deg.C, pref. 100-200 deg.C, under pressure. The pigment thus obtained is washed with water, dried, and crushed, and used as a pigment for cosmetics. The hydrothermal reaction is pref. carried out in water or in a <=3N alkaline solution (e.g. NaOH, KOH solution). By the hydrothermal treatment, the microscopic powders are dissolved and recrystallized to a particle having proper size, and an imperfect crystal is transoformed to a perfect crystal, giving a cosmetic composition having excellent touch. |
