Composition, useful to produce a cosmetic formulation for dyeing hair, comprises a direct hair dye and a carrier system, which comprises lipid vesicles with lipid membrane(s), where the lipid vesicles comprise the direct hair dye

摘要

Cosmetic composition comprises at least one direct hair dye and a carrier system, which comprises lipid vesicles with one or more lipid membrane(s), where: the lipid vesicles comprise the direct hair dye; the lipid vesicles exhibit a positive surface charge; and the positive surface charge is a result of the lipid vesicles comprising positively charged alkyl trimonium salt compounds (I) as charge providers in the lipid membrane(s) in addition to the lipids. Cosmetic composition comprises at least one direct hair dye and a carrier system, which comprises lipid vesicles with one or more lipid membrane(s), where: the lipid vesicles comprise the direct hair dye; the lipid vesicles exhibit a positive surface charge; and the positive surface charge is a result of the lipid vesicles comprising positively charged alkyl trimonium salt compounds of formula (CH 3-(CH 2) n-CH 2-N +(CH 3) 3(X -)) (I) as charge providers in the lipid membrane(s) in addition to the lipids. X -inorganic or organic anion, preferably bromide, chloride, fluoride, iodide, saccharinate, tosylate or methosulfate; and n : 18-28. Independent claims are included for: (1) a cosmetic formulation comprising the composition; and (2) preparing the cosmetic composition, comprising: (a) dissolving a lipid in a short chain aliphatic monoalcohol to obtain a lipid solution, (b) dissolving (I) in the above lipid solution, (c) adding at least one lipophilic direct hair dye in the solution of (b), (d) adding the solution of (c) in an aqueous phase with stirring to obtain an emulsion, (e) adjusting the pH value of the emulsion to 6-7 by the addition of a base, and (f) optionally homogenizing the emulsion by high pressure homogenization at a pressure of 1000-1500 bar; or the steps (a) and (b) as above per se, (c1) adding at least one hydrophilic direct hair dye in an aqueous phase, (d1) adding the solution of (b) in the aqueous phase of (c) under stirring to obtain an emulsion, and the steps (e) and (f) as above per se.