Particles of cured fluorosilicone rubber and cosmetic preparation containing same
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsNaoki Omura, Yoshinori Inokuchi, Satoshi Kuwata
Life of this patent
Estimating the term…
Abstract
Disclosed is a powder consisting of particles of a cured fluoro-silicone rubber having a specified average particle diameter and a specified rubber hardness. The fluorosilicone rubber has a siloxane composition consisting of three types of units expressed by the unit formulas of [R1R2SiO2/2], [R22SiO2/2] and [R23SiO1/2], in which R1 is preferably a 3,3,3-trifluoropropyl group and R2 is preferably a methyl group, in such a proportion that the molar ratio of R1:(R1+R2) is in the range from 0.05 to 0.5. The powder is useful as an ingredient in a cosmetic or toiletry preparation to effect improved sustainability of the cosmetic finish and decreased unevenness of coloring on human skin.
Claims18
A cured fluorosilicone rubber in the form of particles having an average diameter in the range from 0.1 to 100 μm and a rubber hardness in the range from 5 to 90 in the JIS A scale, the fluorosilicone rubber having a composition consisting of the first type units of the unit formula [R1R2SiO2/2], second type units of the unit formula [R22SiO2/2] and third type units of the unit formula [R23SiO1/2], in which R1 is a perfluoroalkyl-substituted alkyl group represented by the general formula Rf(CH2)a—, Rf being a perfluoroalkyl group having 1 to 20 carbon atoms and the subscript a being a positive integer not exceeding 6, and R2 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, in such a proportion that the molar ratio of R1:(R1+R2) is in the range from 0.05 to 0.5.
A cosmetic preparation which comprises:
- (A) a cured fluorosilicone rubber in the form of particles having an average diameter in the range from 0.1 to 100 μm and a rubber hardness in the range from 5 to 90 in the JIS A scale, the fluorosilicone rubber having a composition consisting of the first type units of the unit formula [R1R2SiO2/2], second type units of the unit formula [R22SiO2/2] and third type units of the unit formula [R23SiO1/2], in which R1 is a perfluoroalkyl-substituted alkyl group represented by the general formula Rf(CH2)a—, Rf being a perfluoroalkyl group having 1 to 20 carbon atoms and the subscript a being a positive integer not exceeding 6, and R2 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, in such a proportion that the molar ratio of R1:(R1+R2) is in the range from 0.05 to 0.5;
- and
- (B) ingredients acceptable as the base ingredients of a cosmetic preparation.
Dependencies are inferred from the claim text.