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EGF-mimicking Peptides and Other Topics
By: Charles Fox, Independent Consultant
Posted: January 5, 2009, from the January 2009 issue of Cosmetics & Toiletries.
page 6 of 8Cosmetic pencil cores: Cosmetic pencil cores and their manufacture are described by Mitsubishi Pencil Co., Ltd., and Shiseido Co., Ltd.14 The invention relates to a core material containing a silica porous body and sericite with an average particle size of 3.5-10 µm. More specifically, the core material further contains boron nitride. This core material used in a pencil-type cosmetic, such as pencil-type eye shadow and eyebrow, showed excellent coloring property and mechanical strength with good feeling when used.
Also described is a method for manufacturing the core material including microwave heating treatment of a mixture containing a polysiloxane and a pigment. For example, 50 g tetraethoxysilane was mixed with 50 g ethanol for 1 hr and 100 g of a 0.01 N-HCl solution was dropped therein and further mixed for 6 hr. Thirty parts of the mixture were combined with 20 g black iron oxide, 17.5 g bengala, 27.5 parts sericite (average particle size 6.5 µm) and 15 g kaolinite (average particle size 4.8 µm), extrusion-molded, dried, washed and microwave-heated to give a core brown-color core material with a diameter of 4 mm.
Eyelids and eyebrows: Faber-Castell AG discloses an aqueous cosmetic composition for coloring eyelids and eyebrows.15 The composition contains 0.1-5% polyvinyl pyrrolidone, 4-25% of an alcohol such as ethanol or propanol, 2-15% of a moisturizer, 0.1-5% polyoxyethylene-glycerin-fatty acid ester and/or polyether-modified polysiloxane and a dye, and has a viscosity of less than 50 mPas. An example is shown in Formula 8.
Stabilizing vitamin C derivatives: Oligosaccharides can be used to improve the stability of vitamin C derivatives, according to a three-step method disclosed by Korea Institute of Industrial Technology and Cosmol Co., Ltd.16 In step 1, an aqueous solution of chitosan oligomer is mixed with vitamin C derivatives. In step 2, the pH of the mixture is adjusted to form a complex of chitosan and the vitamin C derivative; the complex is based on the chitosan's amino group combining with the hydroxyl group and carbonyl group of the vitamin C derivative. In the final step, the complex is vacuum-distilled and dried to obtain a powder. The stability of the vitamin C derivatives, which are very sensitive to light or heat, can be improved and the powder can be applied to cosmetics for skin lightening.