WO1993019722A1 - Improvement of the wash-resistance of hair dyes - Google Patents

Abstract

In order to improve the wash-resistance of hair dyes, in particular hair dyes applied on hair which has been already previously damaged, the dyed hair is treated with an aqueous protein composition that contains a dissolved protein, a protein hydrolysate or their water-soluble alkaline salts or alkaline earth salts, preferably an alkaline or alkaline earth caseinate. An aqueous metallic salt composition that forms water-insoluble deposits together with the protein composition is then applied on the hair.

Description

 "Improving the fastness to hair dyeing"

The invention relates to a method for improving the wash fastness of hair dyeing using proteins or protein hydrolyzates and metal salt preparations.

When dyeing hair, two different types of dyes are used:

If only a temporary coloring is desired, the so-called direct dyes are used. Nitrophenylenediamine derivatives, atrachinone derivatives or naphthoquinone derivatives are used, for example, as direct dyes.

However, if permanent hair coloring is to be achieved, ma uses the so-called oxidation hair dye. These hair dyes contain oxidation dye precursors, namely developer substances and possibly coupler substances. The developer substances form the actual dyes under the influence of atmospheric oxygen or other oxidizing agents, for example H2O2, with one another or, in the presence of one or more couplers, under coupling with the coupler substances.

The developer substance used is, for example, primary aromatic amines with another pure or substituted amino group located in the para or ortho position or a hydroxy group, as Coupler substances are, for example, metaphenylenediamines, 3-amiophenols or resorcinols.

In terms of fastness to washing, oxidation hair colors are clearly superior to direct hair dyes. The consumer will then use the direct hair dye if he wishes only temporary hair coloring, which can be removed again by washing the hair several times. However, if the consumer desires permanent hair coloring, he will use oxidation hair dye. Especially in the case of hair dyeing which has been achieved with oxidation hair dyes, an additional improvement in the fastness to washing is therefore desirable, especially since a trend towards more frequent hair washing has been observed among consumers in recent years. However, the fastness to washing of oxidation hair dyeing is not always satisfactory, especially if the hair coloring is in the range of red shades. Hair colorations in the red area of hair previously damaged by previous permanent wave or bleaching treatments are particularly problematic with regard to washing fastness.

There is therefore a need for a method by means of which dyes can be better fixed in the hair and thus the washfastness of hair dyeings can be improved.

It is already known to add proteins, modified proteins or protein hydrolyzates to hair colorants in order to reduce the damage to the hair and to maintain the shine and elasticity of the hair; hair colorants, for example silk fibroin (DE-A-31 39 438), gelatin, albumin, keratin and casein derivatives (DE-A-34 37 360) or also general protein hydrolyzates (EP-A-367926) contain. However, a method for improving the washfastness of hair stains, which includes the use of both proteins or protein hydrolyzates and metal salts, has not been described.

A step-by-step process has now been found with which an improvement in the fastness to washing of hair dyeings can be achieved, but which in principle also applies to other dyed natural fibers, such as, for example, B. wool, silk, feathers, linen, cotton, jute, sisal, regenerated cellulose, modified natural fibers, such as. B. nitro and acetyl cellulose, alkyl, hydroxyalkyl and carboxyalkyl celluloses and synthetic fibers such as. B. polyamide, polyester, polyacrylonitrile and polyurethane fibers can be used.

The process according to the invention is based on first dyeing the dyed hair with a water-containing protein preparation containing a dissolved protein or protein hydrolyzate or its water-soluble alkali or alkaline earth metal salts and then with a water-containing metal salt preparation containing at least one dissolved metal salt which is mixed with the Protein preparation forms water-insoluble precipitates, treated. Examples of water-soluble proteins are egg albumin or casein, and the water-soluble hydrolyzates of collagen (gelatin), keratin, elastin, casein or vegetable protein, such as. B. soy protein, wheat gluten, almond protein, etc. in the form of their alkali or alkaline earth metal salts into consideration. Water-soluble in the sense of the invention means that at 20 ° C. at least 0.5% by weight of the protein, the protein hydrolyzate or their alkali or alkaline earth metal salts can be dissolved in the water-containing preparation.

In the simplest case, the protein preparation is an aqueous solution of the protein, protein hydrolyzate or their water-soluble alkali or alkaline earth salts. In many cases, this simplest embodiment can already be sufficient for treating textile fibers. However, for use on human hair, the proteins, protein hydrolyzates or their water-soluble alkali or alkaline earth salts are preferably incorporated into a water-containing cosmetic carrier. Such carriers are e.g. B. creams, emulsions, gels or surfactant-containing foaming solutions, eg. B. shampoos, or other preparations that are suitable for use on the hair. Components of such preparations can e.g. B. be:

Thickeners which increase the viscosity of the preparation and thus prevent unwanted wetting of other head areas during use on the hair, e.g. B. fatty alcohols, fatty acids, paraffin oils, fatty acid esters and other fat components in emulsified form or water-soluble, polymeric thickeners, eg. B. methyl _* or hydroxyethyl cellulose, starch and vegetable matter,

- Wetting and emulsifying agents such as anionic, nonionic or a phytic surfactants, e.g. B. fatty alcohol sulfates, alkanesulfonates, o-olefin sulfonates, fatty alcohol polyglycol ether sulfates, ethylene oxide addition products to fatty alcohols, to fatty acids, to alkylphenols, to sorbitan fatty acid esters, to fatty acid partial glycerides and fatty acid alkanolamides,

- Hair care additives, such as. B. water-soluble cationic polymers, pantothenic acid, vitamins, plant extracts and cholesterol,

- Reducing agents for stabilizing the proteins or protein hydrolysates, e.g. B. ascorbic acid,

- Perfume oils to cover the protein or protein hydrolyzate's own odor. If necessary, the pH can be adjusted to 5-7 using a pH adjuster.

The step-by-step procedure - after the hair dyeing, first application of the protein preparation and then application of the metal salt preparation - is of crucial importance for the improvement of the wash fastness. Experiments have shown that applying the hair dye and the protein preparation at the same time and then treating it with the metal salt preparation does not lead to an improvement in the fastness to washing of hair dyeings, nor does omitting the protein or metal salt component.

It is known that water-soluble proteins or protein hydrolyzates with average molecular weights of up to approximately 25,000 can still penetrate well into the hair. The process in which the average molecular weight of the protein, the protein hydrolyzate or their water-soluble alkali or alkaline earth salts is at most 25,000 is therefore preferred.

It is not necessary to use a uniform protein or protein hydrolyzate; rather, a mixture of different proteins or protein hydrolyzates can also be used. However, a protein preparation which contains alkali or water-soluble alkaline earth caseinates is particularly preferred.

Another subject of the invention is therefore the method for improving the wash fastness of hair dyeings, in which the water-containing protein preparation contains alkali or water-soluble alkaline earth metal caseinates in a quantity of 0.5 to 10% by weight, based on the total protein preparation.

The actual fixation of the hair dyes by forming a water-insoluble precipitate on the hair surface and in the hair succeeds with all metal salt preparations that form insoluble precipitates with proteins, protein hydrolyzates or their water-soluble alkali or alkaline earth salts. Suitable metal salts are, for example, CaCl2, Ca (N03) 2, MgS04, FeCl2, FeClß, Bi (Nθ3) 3, MnSθ4, CUSO4, Ag 03, Al2 (S04) 3, e (N03) 3, Ce (S04) 2, ZnSθ4 , SnCl2 or (NH4) 2SnCl6.

The metal salt preparation, like the protein preparation in the simplest case, can be an aqueous metal salt solution.

For use on the hair, however, the metal salts are preferably incorporated into a water-containing cosmetic carrier. As components of the cosmetic carrier, the substances already mentioned above for protein preparation come into question. However, the addition of reducing agents should be avoided in the presence of oxidizing metal salts. If necessary, the pH can be adjusted to 5-7.

It should be noted that the salts of some protein or protein hydrolysates are relatively readily water-soluble, so that precipitation does not occur in the lower concentration range due to the addition of further metal salts. The concentrations of the protein preparation to be used according to the invention and the metal salt preparation are therefore to be chosen so high that a visible precipitation occurs when the metal salt preparation is added to the protein preparation at 20 ° C. So z. B. caseinate solutions, the concentrations of which are in the lower limit range, with calcium and magnesium salts are not always satisfactory precipitations. However, increasing the caseinate concentration within the above-mentioned concentrations leads to success in these cases.

It should also be noted that some metal salts themselves are colored compounds or form colored compounds in the presence of proteins and thus change the color shade achieved with the hair dye can. Aqueous preparations of colorless metal salts which form colorless precipitates with proteins, protein hydrolyzates or their water-soluble alkali metal or alkaline earth metal salts are therefore preferred. The invention therefore furthermore relates to the process for improving the fastness to washing of hair dyeings, the aqueous metal salt preparation containing only colorless metal salts which form water-soluble precipitates with the protein preparation. Such metal salts are such. B. A1 ₂ (S04) 3, ^ZπS0 4 ^and (NH ^ SnClö * -.

It is not necessary that the metal salt preparation contain a uniform metal salt, the preparation can also contain a mixture of different metal salts.

The process delivers particularly good results) if the metal salt preparation contains dissolved aluminum ions. Another subject matter of the patent is the process for improving the wash fastness of hair dyeings, where aluminum ions dissolved in the metal saz preparation, preferably in an amount of 0.1 to 2.0% by weight, based on the total aqueous preparation.

A particular improvement in the fastness to washing of hair dyeings over such hair, which has not been subjected to the process according to the invention, can be observed if the hair is already damaged. Damage to the hair occurs in particular as a result of reductive or oxidative hair treatment methods such. B. perm or bleaching. Permanently wavy or bleached hair is dryer, brittle and more porous than untreated hair. It has a greater tendency to adsorb and therefore adsorbs lye more easily. Due to the uneven surface structure, the dyes can also be washed out easily. The method according to the invention is therefore preferably to be used before when the colored hair is ready hair damaged by reductive or oxidative hair treatment methods.

Another subject matter of the patent is a method for coloring hair, which comprises the following steps:

a) treatment of the hair with a hair dye preparation which contains oxidation dye precursors and, if appropriate, oxidizing agents or direct dyes,

b) washing out the excess coloring agent from the hair,

c) drying the hair,

d) treatment of the hair with a water-containing protein preparation containing a water-soluble protein, a protein hydrolyzate or their water-soluble alkali or alkaline earth metal salts,

e) drying the hair,

f) treatment of the hair with a water-containing metal salt preparation containing at least one dissolved metal salt which forms water-soluble precipitates with the protein preparation,

g) washing out the excess metal salt,

h) drying the hair.

All commonly used compounds can be used as oxidation dye precursors and substantive dyes. The Hair dyeing can also be carried out with a mixture of different oxidation dye precursors or a mixture of different direct dyes or with a combination of one or more oxidation dye precursors and one or more direct dyes. The oxidation dye precursor can either as such or in the form of their water-soluble salts with inorganic or organic acids, e.g. B. isolated as hydrochlorides, sulfates, phosphates, acetates, propionates, lactates or citrates and used in de hair dye preparation.

To produce the hair dye preparation, di oxidation dye precursors and any substantive dyes are incorporated into a suitable cosmetic carrier. Such carriers are e.g. B. creams, emulsions, gels or surfactant-containing foaming solutions, eg. B. shampoos, aerosols or other preparations that are suitable for applications on the hair.

The following examples are intended to explain the subject of the invention in more detail, but without restricting it thereto.

Examples

1. Preparation of the hair dye

A coloring cream emulsion based on oxidation dye precursors of the following composition was prepared:

Taig fatty alcohol 10.5 g

Lauryl ether sulfate Na salt (27%) 26.0 g

Paratoluenediamine sulfate 0.18 g

5-amino-2-methylphenol 0.1 g

(NH ₄ ) ₂ S0 ₄ 0.5 g

Na ₂ S0 ₃ (inhibitor) 1.0 g concentrated NH3 solution up to pH = 10.2

Water ad 100 g

The ingredients were mixed together in order. After the oxidation dye precursors and the inhibitor had been added, the pH of the emulsion was first adjusted to 10.2 using concentrated ammonia solution, and the mixture was then made up to 100 g with water.

The oxidative development of the color was carried out with 3% H2O2 solution as the oxidizing agent. For this purpose, 50 g of the coloring cream emulsion were mixed with 50 g of H2O 2 solution (3%) and mixed. 2. Hair dyeing

The coloring cream was then applied to approximately 18 cm long so-called leveling strands weighing approximately 2 g and left there at 27 ° C. for 30 minutes.

Leveling strands are strands of hair with a damaged (lower) part and an undamaged (upper) part. It is produced by tying off strands of hair in the middle and severely damaging the lower part by alternating permanent wave and ultrabonding treatments three times, while the upper part remains untreated.

After the dyeing process was completed, the hair was rinsed, washed with a conventional shampoo and then dried. The result was a red-violet hair coloring.

3. Fixation of the hair stain

A 5% by weight aqueous sodium caseinate solution was prepared from the sodium caseinate (average molecular weight: approx. 22,000) offered by Rovita GmbH under the trade name Rovita FN5.

The colored strands of hair were then immersed in the 5% sodium caseinate solution for 30 minutes, largely freed from liquid by squeezing and then dried.

The strands were then immersed in a 10% by weight Al2 (Sθ4) 3 ^• 18 H2θ solution (corresponding to 0.8% by weight of dissolved aluminum ions) for 10 minutes, freed from excess metal salt by washing with water and then dried. 4. Verification of wash fastness

Each of these strands was shampooed 5 times with a commercially available shampoo, rinsed with water and dried.

The relative dye intensity before and after shampooing was then determined by colorimetry.

The standard (100% dye intensity) is the dye intensity of the undamaged, non-shampooed part of the hair which has not been subjected to the dye fixation according to the invention.

Table 1 Relative color intensities of undamaged hair

unshampooed 5 x shampooed

without color fixation 100% 66%

with color fixation 92% 68 *

The lower color intensity of the unshampooed hair subjected to the dye fixation according to the invention can be explained by the fact that after dyeing the hair, two treatments with aqueous preparations and a washing of the hair according to the invention follow, of course always including some of the dyes will wash. Table 2 Relative color intensities of damaged hair

unshampooed 5 x shampooed

without color fixation 164% 48%

with color fixation 156% 87%

The results show that the color intensities of the undamaged

Part of the hair can be reduced by shampooing 5 times with and without color fixation in a comparable way to an extent that is still tolerable in practice (Table 1).

A different picture emerges with damaged hair sections:

If damaged areas of hair were not subjected to the color fixation according to the invention, there is a very sharp decrease in color intensity from 164% to 48% (Table 2).

However, if the damaged hair sections were subjected to the color fixation according to the invention before shampooing, 87 resulted in a significantly higher residual color intensity (Table 2).

It can be seen that the fastness to washing of hair dyeings, in particular if the hair is already damaged, is improved by the dye fixation according to the invention.

Claims

P a ten t to calls 1. A process for improving the fastness to washing of hair dyeings, characterized in that the dyed hair is firstly containing a water-containing protein preparation containing a water-soluble protein, a protein hydrolyzate or its water-soluble alkali metal or alkaline earth metal salts and then a water-containing metal salt preparation treated at least one dissolved metal salt which gives water-insoluble precipitates with the protein preparation. 2. The method according to claim 1, characterized in that the average molecular weight of the protein, the protein hydrolyzate or their water-soluble alkali or alkaline earth metal salts is at most 25,000. 3. The method according to claim 1 and 2, characterized in that the water-containing protein preparation contains alkali or water-soluble alkaline earth metal caseinates in an amount of 0.5 to 10 wt .-%, based on the total protein preparation. 4. The method according to claim 1 to 3, characterized in that the water-containing metal salt preparation contains only colorless metal salts which form colorless precipitates with the protein preparation. 5. The method according to claim 1 to 4, characterized in that the metal salt preparation contains dissolved aluminum ions, preferably in an amount of 0.1 to 2.0%, based on the total water-containing preparation. 6. Process for hair coloring, characterized by the successive steps: a) treatment of the hair with a hair dye preparation which contains oxidation dye precursors and, if appropriate, oxidizing agents or direct dyes, b) washing out the excess coloring agent from the hair, c) drying the hair, d) treatment of the hair with a water-containing protein preparation containing a dissolved protein, protein hydrolyzate or their water-soluble alkali or alkaline earth metal salts, e) drying the hair, f) treatment of the hair with a water-containing metal salt preparation containing at least one dissolved metal salt which forms water-insoluble precipitates with the protein preparation, g) washing out the excess metal salt, h) drying the hair.