| CPC A61K 8/0295 (2013.01) [A61K 8/29 (2013.01); A61K 8/31 (2013.01); A61K 8/345 (2013.01); A61K 8/37 (2013.01); A61K 8/375 (2013.01); A61K 8/4966 (2013.01); A61K 8/553 (2013.01); A61Q 17/04 (2013.01)] | 9 Claims |
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1. A method for the preparation of a base formulation for a dermatological sunscreen composition comprising the steps of:
producing an oil phase by
(i) heating and homogenizing at a temperature in the range of 80° C. to 96° C. a mixture comprising a capryl triglyceride and/or a coco glyceride, 1 to 8.5 weight percent of phytosqualane, 3.5 to 19.5 weight percent of alkyl benzoate, an organic bisoctrizole based UV-A/UV-B absorbing substance, and at least one additional organic UV absorbing substance selected from the group consisting of hexyl benzoate, bemotrizinol, cyanuric triamide, ethylhexyl triazone, ethylhexyl salicylate, and combinations thereof and optionally coated titanium dioxide, and
(ii) admixing the heated and homogenized mixture of (i) with coated titanium dioxide at a temperature in the range of 70° C. to 82° C.,
wherein the coated titanium dioxide of (i) and (ii) is present in the oil phase in a concentration of 6.5 to 20.5 weight percent, the organic UV absorbing substances of (i) to the coated titanium dioxide of (i) and (ii) are in a ratio of at least 1:1, and the oil phase is present in the base formulation in an amount of 30 to 50 weight percent;
producing a first water phase by heating and homogenizing a mixture comprising 0.5 to 12.5 weight percent of hydrogenated phosphatidylcholine, a polyalcohol, and water at a temperature in the range of 70° C. to 86° C., wherein the heating and homogenization of the hydrogenated phosphatidylcholine forms lamellar structures and the water phase is present in the base formulation in an amount of 30 to 40 weight percent;
mixing the oil phase and the first water phase to form a combined product; and
homogenizing the combined product to form the base formulation for the dermatological sunscreen composition, wherein the oil phase and the first water phase that comprise the base formulation do not separate and all weight percentages are relative to the total weight of the base formulation.
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