Use of hydrophilic-rich alkylmethylsiloxane-dimethylsiloxane-polyoxyalkylene copolymers as emulsifiers for the preparation of cosmetic o/w emulsions of improved aesthetic properties and mildness
This invention relates to the use of hydrophilic-rich, rake-type alkylmethylsiloxane-dimethylsiloxane-polyoxyalkylene copolymers.typical values (ranges) x=10-30 y=2-6 z+q=4-5 (q≦0.8) p=12 R=dodecyl R′=H, MeA hydrophilic-rich alkylmethylsiloxane-dimethylsiloxane-polyoxyalkylene copolymer is hereby defined as an alkylmethylsiloxane-dimethylsiloxane-polyoxyalkylene copolymer possessing sufficient hydrophilic content such that it can be readily taken up by water at a concentration of at least 15% by mass copolymer with simple stirring at room temperature to yield a stable dispersion of micron and sub-micron sized particles. This definition supercedes the typical values of the formula variables x, y, z, q, and p specified above to include all values that result in the copolymer being hydrophilic-rich. This definition also supercedes the typical identity of R=dodecyl shown above to include R being any alkyl or branched-alkyl chain of any length such that the resulting copolymer is hydrophilic-rich. This definition also supercedes the typical identity of the polyoxyalkylene shown above to include polyoxyalkylenes possessing propylene oxide repeat units as well as ethylene oxide repeat units such that the resulting copolymer is hydrophilic-rich. This definition also supercedes the typical identity of R′=H, Me shown above to include any alkyl, aryl, or acyl radical such that the resulting copolymer is hydrophilic-rich. This invention also relates to the use of these copolymers as emulsifiers for the preparation of cosmetic O/W formulations (defined as stable O/W emulsions of water, one or more oils that may include silicone oils, and various other ingredients that may include preservatives, fragrances, coloring agents, etc.) that yield improved aesthetic properties (including appearance and texture of the cosmetic emulsion, initial feel on the skin, and final feel on the skin after rub-out) and imp
