GB1294500A - Hot bleaching of human keratinic fibres - Google Patents

Abstract

1294500 Bleaching and dyeing hair L'OREAL 9 July 1970 [9 July 1969 25 Feb 1970] 33471/70 Headings D1B and D1P Human keratinic fibres are bleached by applying thereto a composition comprising an oxidising agent conventionally used for bleaching human keratinic fibres and at least one active ingredient having the formula: in which each of R 1 and R 2 , which may be the same or different, represents a hydrogen atom, a C 1-5 alkyl radical, a hydroxymethyl radical or an alkoxymethyl radical, the alkoxy group of which has 1-5 C atoms; or R 1 and R 2 together represent a -CH 2 -CH 2 - radical thus forming with the adjacent N atoms and intermediate C atom a 5-membered ring, which radical may be substituted by hydroxyl or alkyl groups; R 3 represents a -O-R 5 or group, in which R 5 represents a hydrogen atom or a C 1-5 , alkyl radical and each of r and r<SP>1</SP>, which may be the same or different, represents a C 1-5 alkyl radical, or r and r<SP>1</SP> together with the N atom to which they are attached form a ring optionally containing an additional hetero-atom; and R 4 represents a hydrogen atom, a C 1-5 alkyl radical or a -CH 2 -R 3 group. Specified active ingredients are mono- and di-methylolthiourea, methoxymethylthiourea, mono- and di-methylolethylenethiourea, mono- and di-morpholinomethylthiourea, and dimorpholinomethylethylenethiourea. The oxidising agent may be hydrogen peroxide optionally in admixture with a peroxide, e.g. urea peroxide, or a per-salt, e.g. sodium or potassium percarbonate or persulphate. The composition may also contain a dyestuff such as a disperse, complexed or soluble azo dyestuff or a nitro dyestuff. It may be prepared in the form of a two-component pack, one component being the active ingredient (plus dyestuff if required) and the other component being the oxidising agent. Where compositions are used which have an alkaline pH at the end of treatment, the hair is subsequently rinsed with an acidic solution, e.g. of lactic, acetic or formic acid. On application, the compositions undergo a spontaneous rise in temperature which accelerates the bleaching effect. They also strengthen the hair, and, in cases in which nascent sulphur is liberated, they have an anti-seborrhoeic effect.