Oil-in-water emulsion sunscreen cosmetic

Patent metadata

Field	Value
Publication number	US-10238585-B2
Application number	US-201214353497-A
Country	US
Kind code	B2
Filing date	Oct 10, 2012
Priority date	Oct 27, 2011
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

The present invention is intended to provide an organic UV absorber-free, non-chemical sunscreen cosmetic that contains hydrophobized zinc oxide and/or hydrophobized titanium dioxide as a UV scattering agent, specifically an oil-in-water emulsion sunscreen cosmetic that provides excellent emulsion stability and an excellent pleasant feel while maintaining high levels of UV protection.

First claim

The invention claimed is:

1. An organic UV absorber-free, oil-in-water emulsion sunscreen cosmetic that comprises:
(A) zinc oxide and/or titanium dioxide;
(B) isostearic acid;
(C) a silicone containing a carboxyl group;
(D) a non-ionic surfactant;
(E) sodium carboxymethyl cellulose; and
(F) water;

wherein said (A) zinc oxide and/or titanium dioxide is:
hydrophobized with octyltriethoxysilane and/or dimethylpolysiloxane; and
homogeneously dispersed in an oil phase with said (C) silicone containing a carboxyl group acting as a dispersant; and

wherein the dispersibility of the zinc oxide or the titanium dioxide lowers without said (B) isostearic acid wherein (C) the silicone containing a carboxyl group is carboxydecyl trisiloxane.

2. The oil-in-water emulsion sunscreen cosmetic according to claim 1 , wherein the contents of the components (A) to (E) with respect to the total amount of the oil-in-water emulsion sunscreen cosmetic are:
3 to 35 mass % for (A) the zinc oxide and/or the titanium dioxide hydrophobized with octyltriethoxysilane and/or dimethylpolysiloxane;
0.1 to 2 mass % for (B) the isostearic acid;
0.1 to 1.5 mass % for (C) the silicone containing a carboxyl group;
0.5 to 4.5 mass % for (D) the non-ionic surfactant; and
0.1 to 1 mass % for (E) the sodium carboxymethyl cellulose.

3. The oil-in-water emulsion sunscreen cosmetic according to claim 1 , further comprising:
(G) a natural polymer or a synthetic high polymer.

4. The oil-in-water emulsion sunscreen cosmetic according to claim 2 , further comprising:
(G) a natural polymer or a synthetic high polymer.

5. A method for making the organic UV absorber-free, oil-in-water emulsion sunscreen cosmetic of claim 1 , the method comprising the steps of:
hydrophobizing (A) the zinc oxide and/or titanium dioxide with octyltriethoxysilane and/or dimethylpolysiloxane; and
dispersing the hydrophobized zinc oxide and/or titanium dioxide homogeneously in an oil phase with (C) carboxydecyl trisiloxane acting as a dispersant;

wherein the dispersibility of the zinc oxide or the titanium dioxide lowers without (B) the isostearic acid.

Assignees

• Ishida Kahori
• Harada Taichi
• Ikebe Yosuke
• Shiseido Co Ltd

Inventors

• Ishida Kahori
• Harada Taichi
• Ikebe Yosuke

Classifications

• A61K8/891

  saturated, e.g. dimethicone, phenyl trimethicone, C24-C28 methicone or stearyl dimethicone · CPC title

• A61K8/585

  Organosilicon compounds · CPC title

• A61K8/27

  Zinc; Compounds thereof · CPC title

• A61Q17/04

  Topical preparations for affording protection against sunlight or other radiation; Topical sun tanning preparations · CPC title

• A61K8/731

  Cellulose; Quaternized cellulose derivatives · CPC title