| 摘要 |
The present invention relates to a-AI2O3flakes prepared by a process comprising the following steps: (1) preparation of an aqueous solution of at least one water-soluble and/or insoluble aluminum salt which optionally contains at least one sulfate compound, (2) adding a basic solution and optionally at least one dopant to the aluminum salt solution (1),(3) drying of the obtained gel, followed by calcination to obtain AI2 03 flakes and alkali salts in a molten salt, (4) removal of the water soluble parts of the calcined molten salt obtained in step (3). The flakes have a D50 -value of 5-15 μιm, a D80 -value of less than 20 μm, a particle thickness of < 500 nm and a Mill value (average friction coefficent measured by the KES friction tester) of less than 0.8. The flakes can be coated with one or more metal oxides and used in a variety of applications, especially in cosmetics. Preferably, the present invention relates to a filler pigments for cosmetics. |
