FI94590B - Hair care products to prevent oxidative damage to the hair - Google Patents

Abstract

It has emerged that residues of hydrogen peroxide in human hair result in oxidation damage. This can be prevented with a water-soluble product which is in the form of a powder or tablet and which preferably contains 5 to 50 per cent by weight of ascorbic acid or the salts or derivatives thereof. The ascorbic acid, which is coated, for example, with silicone or ethylcellulose, can be stored in a formulation of this type for a relatively long time and dissolved in water only when used. This can take place with the aid of sodium bicarbonate with an effervescent action. A hair-care composition of this type is extremely well tolerated by hair and skin.

Description

- 94590

This invention relates to a hair conditioner for preventing oxidative damage to hair caused by hydrogen peroxide, and is water-soluble in the form of a powder or tablets.

It is known that hydrogen peroxides are formed in human hair, especially in UV radiation or in a humid state. In addition, it is known that after treatment with hydrogen peroxide or persulfate, residues of hydrogen peroxide remain in the hair, which cannot be removed by rinsing and washing vigorously with shampoo.

After some time, the hydrogen peroxides in the hair cause a certain lightening of the hair, which is associated with undesirable hair damage, which means that the hair becomes weak and brittle. The obvious negative effect on the hair becomes apparent when the hair is bleached using per-sulfates. It is not possible to dye the hair bleached in this way evenly with oxidative dyes, nitroaminobenzenes or nitroaminophenols afterwards. Also, the hair color obtained by the previous treatment changes many times afterwards in an undesirable and uneven way.

This is mainly due to the fact that after the use of persulphates and hydrogen peroxide, peroxide residues appear in the hair after days or even weeks. (For example, using the Merck AG, Darmstadt, BRD, Merkoguant peroxide test). In general, oxidative damage to the hair due to reactive oxygen species (H2O2) always occurs. Peroxide is always and demonstrably present after dyeing, tinting, bleaching and permanent fixing treatment.

The removal of reactive oxygen species (H 2 O 2) is thus a prerequisite for maintaining the health of chemically treated hair. Attempts have been made to treat human hair with substances which decompose hydrogen peroxides to remove or prevent the formation of hydrogen peroxide residues in the hair.

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However, a difficult problem is how the hair and skin tolerate the reducing agent. This is particularly complicated by the fact that such reducing agents are often sensitive to air, light, heat and humidity. As a result, their storability in aqueous solutions is also very limited. The invention is thus based on the object of developing a hair care agent in order to avoid oxidative damage to the hair, in which case the hair care agent must be a substance which is well tolerated by the hair and skin and whose storability is considerably improved. This function is fulfilled by a hair conditioner having the features of claims 1.

Experiments have shown that ascorbic acid is particularly suitable as a reducing agent which is tolerated by hair and skin and which reduces hydrogen peroxide residues after dyeing, tinting, bleaching and permanent fixation treatment. The amount by weight of ascorbic acid used in the crystalline form can be varied almost arbitrarily. The proportion by weight of ascorbic acid is preferably: 5 to 50%. The shelf life and stability of the hair conditioner are improved by the use of coated ascorbic acid. For example, silicone-coated ascorbic acid, type SC, and ethylcellulose-coated ascorbic acid, type EC, are both available from F. Hoffman - La Roche & Co. KG. AG, ‘Base / Schweiz.

It is possible to add known powdered, water-soluble, cationic compounds without reducing the effect of ascorbic acid. In this way, all the desired effects of the after-treatment agent are achieved, such as better combability of the hair when dry and • wet, shine, flexibility and treatment in general.

Particularly suitable for this purpose are quaternary ammonium compounds, such as cetyltrimethylammonium bromide. Copolymers of hydroxyethylcellulose and a quaternary ammonium compound are also suitable. For example, a company. 94590 3

National and Chemical Corporation, Bridgewater, New Jersey, USA, offers a copolymer of Celquat L 200 hydroxyethylcellulose and diallyldimethylammonium chloride which is well suited.

To bind heavy metal residues, a complexing agent can be added to the hair conditioner, which also retains its effectiveness in strongly calcified water. A particularly suitable complexing agent is, for example, ethylenediaminetetraacetic acid (EDTA) or its sodium salt.

The water solubility of quaternary ammonium compounds is accelerated by the addition of sodium hydrogen carbonate, which reacts with acids during effervescence. The proportion of ascorbic acid required for this reaction can be replaced by a less expensive acid, for example tartaric acid or citric acid.

Caking of the hair conditioner in powder form can be avoided by adding the highly dispersible, amorphous silica provided by Degussa AG, Frankfurt, BRD, under the name Aerosil.

If desired, it is also possible to mix the perfume in a small amount into the product.

'Sugar or sugar alcohols are added as excipients, for example anhydrous D (+) glucose is used, which is particularly suitable because it is highly tolerated by the skin. The pH of the hair conditioner to be mixed with water can be adjusted arbitrarily, however, so that the pH of the solution is 5.0 to 8.5. Hydrogen peroxide-treated hair, when treated with the hair conditioner according to the invention, shows no more hydrogen peroxide residues after 2-5 minutes. Also in the oxidative coloring of the hair, which is carried out on the hair bleached with persulfate compounds, the intermediate coloring with the hair care agent of the invention gives a uniform coloring result.

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The following are three examples (a-c) of hair care product recipes of the invention. All amounts are by weight:% a) Ethylenediaminetetraacetic acid (EDTA) 0.100

Celquat L 200 4,000

Aerosil 200 0.500

Cetyltrimethylammonium bromide, ground 15,000 Ascorbic acid, type EC 15,000

Sodium bicarbonate, purest anhydrous 7,500

Sorbitol, ground, anhydrous 57,900 100,000% b) Ethylenediaminetetraacetic acid Na (EDTA Na2) 0.100

Celquat L 200 5,000

Aerosil 300 0.600

Cetyltrimethylammonium bromide, ground 12,000 Tartaric acid, ground, purest 5,000

Ascorbic acid, type SC 5,000

Sodium bicarbonate, purest anhydrous 8,500

Mannitol, ground, anhydrous 63,800 100,000:% c) Ethylenediaminetetraacetic acid Na (EDTA Na4) 0.100

Celquat L 200 5,000

Cetyltrimethylammonium bromide, ground 15,000 Tartaric acid, ground, purest 9,000

Ascorbic acid, type SC 6,000

Sodium bicarbonate, purest anhydrous 12,500

Glucose, powdered, anhydrous 51,630

Aerosil 200 0.700

Perfume 0.070 100,000 - 94590 5

The above recipes are easy to use, as the following examples show. Shortly before use, the hair conditioner packed in an airtight box is dissolved in a ratio of 1: 3 to 1: 4 in cold or lukewarm water by effervescence.

Examples 1. Human hair is permanently subjected to conventional thioglycollate solutions, fixed with hydrogen peroxide, rinsed, and after-treated for about 2-5 minutes with one solution of said examples a-c.

2. Human hair is bleached using ammonium and / or potassium persulfate and hydrogen peroxide in a conventional manner and a post-treatment lasting 2-5 minutes is performed with one solution of said examples a-c.

3. Human hair is conventionally dyed with a hair conditioner based on oxidative dyes using hydrogen peroxide or hydrogen peroxide donors, for example percarbamide-hydrogen peroxide urea, and post-treated for 2-5 minutes with one solution of said examples a-c.

The hair treated according to Examples 1-3 is free of: no detectable peroxide residues. It is possible to dye the hair treated according to Example 3 with oxidative dyes beautifully evenly.

During preparation, all components are screened with 0.5 mm V2A. with a steel sieve (silica and perfume are mixed separately) and then mixed homogeneously in a suitable powder mixer.

Claims (12)

1. Curing agent for the avoidance of oxidative damage caused by hydrogen peroxide, which is water-soluble in the form of powder or tablets, characterized in that the product contains at least the following components: a water-soluble cation-active compound in powder form, a copolymer of hydroxyethyl cellulose and a quaternary ammonium sodium compound, sodium hydrogen carbonate to improve water solubility and as a hard and skin-tight oxidizing agent coated ascorbic acid. 2. Additive according to claim 1, characterized in that it contains 5-50% by weight of ascorbic acid. 3. Additives according to claim 1, characterized in that the ascorbic acid is coated with silicone or ethyl cellulose. 4. Additives according to claim 1, characterized in that it contains as a cationic compound a quaternary ammonium compound. 5. Additive according to claim 4, characterized in that it contains as a quaternary ammonium compound cetyltrimethylammonium bromide. 6. Additives according to claim 1, characterized in that it contains a copolymer of hydroxyethyl. cellulose and diallyldimethylammonium hydrochloride. 7. Additive according to claim 1, characterized in that it contains as complexing agent ethylenediaminetetraacetic acid (EDTA) or its sodium salts. - 94590 8. Additives according to claim 1, characterized in that it contains tartaric or citric acid for reaction with sodium hydrogen carbonate. 9. Additives according to claim 1, characterized in that it contains sugar or sugar alcohols as fillers. 10. Additive according to claim 9, characterized in that it contains D (+) glucose anhydrous. 11. Additive according to claim 1, characterized in that it contains well dispersible amorphous silica. 12. Additives according to claim 1, characterized in that it contains perfume.