Composite powder, cosmetics containing the same, and process for producing composite powder
AssigneeShiseido Company, Ltd.
InventorsKatsuki Ogawa, Kyoko Joichi, Tsuyoshi Miyamoto, Tetsuya Kanemaru, Katsuhiko Yagi
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Abstract
An object of the present invention is to provide a composite powder, cosmetics containing the same, and the production method of the same. When blended into cosmetics, the above-described composite powder corrects skin surface unevenness and imperfections in skin color, renders a natural finish, and have durability in finished makeup. In order to achieve the above-mentioned object, the composite powder of the present invention comprises flaky substrate powder and barium sulfate particles or zinc oxide particles that adhere to the surface, in protrusions, of the substrate powder.
Claims20
A composite powder comprising:
- a) a flaky substrate powder,
- b) seed particles selected from the group consisting of titanium oxide, zinc oxide, alumina, aluminum hydroxide, silica, iron oxide;
- and
- c) barium sulfate particles or zinc oxide particles;
- wherein
- i) the seed particles act as nuclei on the surface of the flaky substrate powder and the barium sulfate particles or the zinc oxide particles adhere to the flaky substrate powder particles through the seed particles, and
- ii) the coverage with barium sulfate particles is 10-70% with respect to the surface area of said substrate powder or the coverage with zinc oxide particles is 40-90% with respect to the surface area of said substrate powder.
A method of producing a composite powder comprising a flaky substrate powder, seed particles and adhering barium sulfate particles comprising the steps of:
- a) preparing a slurry solution of a flaky substrate powder,
- b) separately preparing a solution of seed particles,
- c) adding the solution of seed particles to the slurry solution of the flaky substrate powder,
- d) separately preparing a barium ion solution,
- e) separately preparing a sulfate ion solution,
- f) adding the barium ion solution and the sulfate ion solution separately to the slurry solution comprising seed particles and the flaky substrate powder,
- g) allowing the barium ion solution and the sulfate ion solution to react and form barium sulfate particles;
- wherein
- i) the seed particles act as nuclei, and
- ii) the barium sulfate particles adhere to the flaky substrate powder particles through the seed particles.
A method of producing a composite powder comprising a flaky substrate powder, seed particles and adhering zinc oxide particles comprising the steps of:
- a) preparing a slurry solution of a flaky substrate powder,
- b) separately preparing a solution of seed particles,
- c) adding the solution of seed particles to the slurry solution of the flaky substrate powder,
- d) separately preparing a zinc ion solution,
- e) separately preparing an alkali aqueous solution,
- f) adding the zinc ion solution and the alkali aqueous solution separately to the slurry solution comprising seed particles and the flaky substrate powder,
- g) allowing the zinc ion solution and the alkali aqueous solution to react and form zinc oxide particles;
- wherein
- i) the seed particles act as nuclei, and
- ii) the zinc oxide particles adhere to the flaky substrate powder particles through the seed particles.
Dependencies are inferred from the claim text.