Back to results
US 4,361,421 AGranted
Hair-dyeing compositions based on para-phenylenediamines
AssigneeL'oreal
InventorsAndree Bugaut, Ginette Jeanminet
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeL'oreal
InventorsAndree Bugaut, Ginette Jeanminet
Estimating the term…
The invention relates to hair-dyeing compositions based on para-phenylenediamine. These compositions contain, as the oxidation dyestuff, para-phenylenediamine and one or more para-phenylenediamines of the formula ##STR1## in which R denotes alkyl or hydroxyalkyl and R' denotes a hydroxyalkyl group, and also their cosmetically acceptable salts, in a molar ratio para-phenylenediamine/compound(s) of the formula (I), expressed in terms of free bases, which is such that, after the addition of an equal volume of hydrogen peroxide of 20 volumes strength and application to the hair for 30 minutes, no Bandrowsky's base is detected in the oxidizing dyeing composition. These compositions make it possible to obtain natural background colorations, ranging from black to light chestnut, of very good quality.
A composition suitable for dyeing hair which contains, in a cosmetically acceptable medium, para-phenylenediamine or a cosmetically acceptable salt thereof and one or more compounds corresponding to the formula (I) ##STR4## in which R denotes an alkyl or hydroxyalkyl group and R' denotes a hydroxyalkyl group, the alkyl groups having 2 to 4 carbon atoms, or a cosmetically acceptable salt thereof, in a molar ratio para-phenylenediamine/compound(s) of the formula (I) which is about 0.5:1 in the case the composition contains para-phenylenediamine in an amount of 1.5 to 2.5% by weight and does not exceed 1:1 and is not less than 0.5:1 in the case para-phenylenediamine is present in an amount of 0.2 to 1.5% by weight.
Dependencies are inferred from the claim text.