AU751700B2 - Process for the oxidative dyeing of human hair - Google Patents

Abstract

Process for oxidative dyeing of human hair comprises (1) treating the hair with an alkaline oxidation dye mixture containing at least 1 developer, at least 1 coupler and an oxidizing agent and leaving it to act for 5-30 minutes; (2) treating the hair, without an intermediate rinse, with an acidic composition containing at least 1 acid; and (3) rinsing.

Description

AUSTRALIA

Patents Act 1990 Goldwell GmbH C

C.

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title.

Process for the oxidative dyeing of human hair The following statement is a full description of this invention including the best method of performing it known to us:- A-21/98 Process for the Oxidative Dyeing of Human Hair The present invention concerns a new process for the oxidative dyeing of human hair which is not only more gentle to the hair than customary processes but which also provides improved coverage, color intensity and stability.

It is still customary to dye human hair by the use of oxidation hair dyestuffs mixed immediately prior to use with oxidizing agent compositions, in particular on the basis of diluted hydrogen peroxide, and then applying to the hair.

The pH-value of these ready-to-use compositions is generally in the alkaline range, in particular at pH-values between about 9 and about 11.

This alkaline treatment of the hair may damage the structure thereof, in particular in the event of frequent repetition, and especially when the hair so treated was already subjected to previous damage. After coloration, this porous hair also shows poor color fastness.

It has already been proposed to overcome these disadvantages of customary hair dyeing by replacing the alkaline dyeing compositions by an analogous composition with a pH-value within the slightly acidic area between about 5.9 and 6.9.

Such compositions as described, for example, in DE-A No. 35 30 270, 36 28 397 and 36 28 398, have indeed proven substantially less damaging to hair than alkaline products.

In some cases, however, i.e. in the preparation of special shades, the intensity and stability of the colorations achieved with these compositions is not fully satisfactory.

The invention intends to overcome these disadvantages.

The solution of this problem consists in the use of a new process for the oxidative dyeing of human hair, comprising the following steps: Application to the hair of an alkaline oxidation dyestuff mixture comprising at least one developing and at least one coupling substance as well as an oxidizing agent, subsequently, preferably after about ten to thirty minutes processing, without rinsing, application of a composition comprising at least one acid, and rinsing the hair after processing.

o* go. o O** A-21/98 -2- By use of this process, a gentle dyeing of the hair is achieved, providing excellent color intensity. The time required for dyestuff processing can be reduced by about 25% to through application of heat, preferably about 300 bis 50 for example about 40 C.

The alkaline oxidation dyestuff compositions used in the first step of the treatment, comprising at least one developing and one coupling substance as well as an oxidizing agent, are known per se.

Regarding these ready-to-use mixtures containing the peroxide), the pH-value of which ranges between about 8 and 11, preferably 9 and 10, in particular about 9.5, reference is made, for example, to the monography of K. Schrader, "Grundlagen und Rezepturen der Kosmetika", 2nd Ed., pp. 784-804 (1989); the compositions described therein are useful within the scope of the invention, as well as additional developing and coupling substances and shading agents, known from the extensive state of the art.

Examples of developing substances are in particular 1.4-diaminobenzene, tetraaminopyrimidines, triaminohydroxypyrimidines, 1.2.4-triaminobenzene, 2-(2.5-diaminophenyl)ethanol, 2-(2'-hydroxyethyl amino)-5-aminotoluene and 1 -amino-4-bis-(2'hydroxyethyl)-aminobenzene, or the water-soluble salts thereof; examples for coupling substances are resorcinol, 2-methyl resorcinol, 4-chlororesorcinol, 2-amino-4-chlorophenol,4- (N-methyl) aminophenol, 2-aminophenol, 3-aminophenol, 1 -methyl-2-hydroxy-4aminobenzene, 3-N,N-dimethyl aminophenol, 4-amino-3-methyl phenol, 5-amino-2-methyl phenol, 6-amino-3-methyl phenol, 3-amino-2-methyl amino-6-methoxypyridine, 2-amino-3hydroxypyridine, 4-aminodiphenylamine, 4.4'-diaminodiphenylamine, 2-dimethyl aminopyridine, 2.6-diaminopyridine, 1.3-diaminobenzene, 1-amino-3-(2'-hydroxyethyl amino)benzene, 1 -amino-3-[bis(2'-hydroxyethyl) amino]benzene, a-naphthol, 1.4-diamino-2chlorobenzene, 4.6-dichlororesorcinol, 1.3-diaminotoluene, 4-hydroxy-1.2-methylene dioxybenzene, 1.5-dihydroxynaphthaline, 1.7-dihydroxynaphthaline, 2.7dihydroxynaphthaline, 1-hydroxynaphthaline, 4-hydroxy-1.2-methylene dioxybenzene, 2.4diamino-3-chlorophenol and/or 1-methoxy-2-amino-4-(2'-hydroxyethyl amino)benzene, whereby this list is just exemplary.

Developing and coupling substances are preferably contained in a molar proportion of 1:3 to 5:1, in particular about 1:1 and about 3:1; their proportion in the dyestuff compositions according to the invention may range from about 0.25% to about 5% by weight, depending on the desired coloration.

S. *S 5* A-21/98 -3- Useful as oxidation agents are especially diluted hydrogen peroxide solutions, emulsions or gels; possible but less customary is also the use of further peroxides such as earth alkali peroxides, urea peroxide, melamine peroxide, etc., in the respective stoichiometrical amounts.

The oxidation dyestuff compositions can be used as solutions, creams, pastes, gels, aerosols, etc..

The processing time on the hair preferably is about five to thirty minutes, especially about to about 20 minutes, for example, about 15 minutes each for the alkaline and acidic dyestuff mixtures. The process according to the invention is suited both for overall, i.e. first-time coloration of the hair and for freshen-up treatments.

It may be advisable to have a slightly longer processing time of the alkaline dyeing composition compared to the acidic composition.

The acidic composition, applied to the hair after processing of the alkaline oxidation dyestuff precursor composition, has a pH-value ranging especially between about 2 and about 6, in particular about 2.5 and 5, and can be a solution or a thickened gel.

Useful as acids are basically all inorganic and organic acids, such as, in particular phosphoric acid, acetic acid, propionic acid, oxalic acid, malonic acid, amino acids, hydroxycarboxylic acids, such as lactic acid, tartaric acid, citric acid, malic acid, gluconic acid, glycolic acid, sorbic acid, aromatic carboxylic acids, such as benzoic acid, salicylic acid, phthalic acid, the acidic salts and mixtures thereof.

Preferred are organic acids, such as citric acid, tartaric acid, lactic acid, maleic acid, etc..

Upon application to the hair of the acidic dyeing composition, the pH-value preferably ranges between about 5 and 8, especially about 6 to The following Examples illustrate the invention.

A-21/98 -4- Example 1 A hair dyeing composition obtained by admixture of equal weight proportions of a 6% hydrogen peroxide solution and an oxidation dyestuff precursor of the following composition with a pH-value of 9.8 was applied onto strands of bleached human hair.

Carrier composition Cetyl stearyl alcohol Oleic acid Stearic acid monoethanolamide Coco fatty acid monoethanolamide Sodium lauryl sulfate Sodium sulfite 1.2-Propanediol Ascorbic acid Ammonium chloride EDTA, Tetrasodium salt Perfume Wheat protein hydrolyzate Silica Oxidation dyestuff composition 11.00 by wt.) 5.00 2.50 2.50 2.50 1.70 1.00 1.00 0.50 0.50 0.20 0.40 0.20 0.10 2.5.6-Triamino-4-hydroxypyrimidine sulfate sulfate 4-Chlororesorcinol Resorcinol 3-Aminophenol 0.01 0.55 0.17 0.05 0.03 Water ad 100.00 After 15 minutes processing without rinsing, a 12.5% aqueous citric acid gel was applied to the hair in an amount corresponding to the initially used dyeing composition. The mixture was thoroughly combed through the hair, achieving a pH-value of about 7, was processed for further 15 minutes and subsequently rinsed with water, and dried.

A-21/98 A strong, intensive, expressive medium-blond coloration was obtained, which remained unchanged even after five shampoo treatments.

Strands treated in the same manner for 30 minutes with only the alkaline dyestuff composition by comparison showed a weaker coloration, which was clearly less intensive in color after five shampoo treatments than the coloration obtained by the process according to the invention. Furthermore, after the exclusively alkaline color treatment the hair had a clearly more rough feeling.

Example 2 Into a carrier composition according to Example 1, the following oxidation dyestuff mixture was incorporated: 2.5.6-Triamino-4-hydroxypyrimidine sulfate 0.01 by wt.) sulfate 0.90 2-Amino-4-hydroxypyridine 0.80 1 -Naphthol 0.17 3-Aminophenol 0.10 Resorcinol 0.03 This composition was mixed with a 6% H 2 0 2 solution in a weight proportion of 1:1 (pH and applied to strands of bleached human hair.

After 15 minutes processing without rinsing, an aqueous 15% tartaric acid gel was applied to the hair in an amount corresponding to the initially used dyeing composition. The hair was combed through thoroughly, thus achieving a pH-value of about 6; after further processing of minutes the hair was rinsed with water, shampooed and dried.

An intensive, glossy mahogany coloration was obtained, which was still stable after five shampoo treatments.

After application of an alkaline composition only, the hair not only showed a less intensive coloration, it also had a rough feeling.

A-21/98 -6- Example 3 Into a carrier composition according to Example 1 the following oxidation dyestuff mixture was incorporated: sulfate 0.80 by wt.) Resorcinol 0.30 2-Amino-4-hydroxypyridine 0.06 3-Aminophenol 0.03 This composition was mixed with a 6% H 2 0 2 solution in a weight proportion of 1:1 (pH 9.6) and applied to strands of bleached human hair.

After 20 minutes processing, without rinsing, an aqueous 15% citric acid solution was applied to the hair in an amount corresponding to the initially used dyeing composition. The hair was combed through thoroughly, thus achieving a pH-value of about 6; after further processing of minutes the hair was thoroughly rinsed and dried.

An intensive red-brown coloration was obtained, which was still stable after five shampoo treatments, giving the hair a soft, supple body.

Claims (6)

1. Process for the oxidative dyeing of human hair, wherein first an alkaline oxidation dyestuff composition, comprising at least one developing and at least one coupling substance as well as an oxidizing agent is applied-to the hair, and subsequently, after about five to thirty minutes processing, without rinsing, an acidic composition comprising at least one acid is applied, and the hair is rinsed after processing.

2. Process according to claim 1, wherein the processing time of the composition in the second treatment step is equal to or shorter than that of the first treatment step.

3. Process according to claims 1 or 2, wherein the dyestuff composition is processed at about 300 to about 50' C.

4. Process according to one or more of claims 1 to 3, wherein the alkaline oxidation dyestuff composition has a pH-value of 8 to 11. Process according to one or more of claims 1 to 4, wherein the composition comprising at least one acid has a pH-value of 2 to 6.

6. Process according to one or more of claims 1 to 5, wherein at least one of the acidic components is selected from the following acids: citric acid, tartaric acid, lactic acid and/or malic acid.

7. Process according to one or more of claims 1 to 6, wherein, after application of the composition comprising the acid, the pH-value of the dyeing mixture on the hair ranges between about 5 and 8.