| US 7,559,956 B2 | ||
| Use of a cationic hydrotrope for the direct dyeing of keratinous fibres, composition comprising it and colouring processes employing it | ||
| Maxime De Boni, Paris (France); and Alain Lagrange, Coupvray (France) | ||
| Assigned to L'Oreal S.A., Paris (France) | ||
| Filed on May 17, 2007, as Appl. No. 11/798,939. | ||
| Claims priority of provisional application 60/810653, filed on Jun. 05, 2006. | ||
| Claims priority of application No. 06 51871 (FR), filed on May 22, 2006. | ||
| Prior Publication US 2008/0086824 A1, Apr. 17, 2008 | ||
| Int. Cl. A61Q 5/10 (2006.01) | ||
| U.S. Cl. 8—405 [8/406; 8/426; 8/435; 8/547; 8/570; 8/583; 8/606] | 17 Claims |
1. A method for dyeing keratinous fibers comprising applying to the keratinous fibers a dyeing composition comprising at least
one direct dye and at least one cationic hydrotrope of following formula (I):
 X represents the CH or N+R6 group with R6 representing a linear or branched C1-C10 alkyl radical;
R1 represents:
a hydrogen atom or a linear or branched C1-C10 alkyl radical, if X represents N+R6, or
a (CH2)nN+R3R4R5 radical with R3, R4 and R5, which are identical or different, representing a linear or branched C1-C10 alkyl radical and n representing an integer between 0 and 12, if X represents CH;
R2 represents a linear or branched C1-C4 alkyl radical; and
p has the value 0 or 1;
wherein the electrical neutrality of the compound is provided by a cosmetically acceptable anion or a mixture of cosmetically
acceptable anions, and
wherein the dyeing composition does not comprise benzyltrimethyammonium salt or benzyltriethylammonium salt.
|