METHOD OF REDUCING COLOUR LOSS FROM DYED HAIR USING ORGANIC AMINO COMPOUNDS

Abstract: A method for reducing colour loss from hair treated with an oxidative composition, such as an oxidative hair dye, the method comprising the step of contacting the hair, either prior to or after treatment of the hair with the oxidative composition, with a colour protective composition comprising an organic amino compound selected from: (i) basic amino acids; (ii) urea; (iii) guanidine; (iv) salts and/or derivatives of any of (i) to (iii); (v) mixtures of any of (i) to (iv).

Description: Although permanence is the objective of such oxidative dyeing methods, in practice it is difficult to achieve. The colour tends to fade over time and a contributory factor in fading is lack of wash-fastness. This means that the colour tends to leach out of the hair after repeated washing. This leads to gradual fading or changing of the applied colour. The action of other factors such as ultraviolet light, combing and perspiration also affects the colour. We have now found that certain selected organic amino compounds, in particular arginine and urea, are effective for reducing colour loss from hair previously or subsequently treated with an oxidising agent such as an oxidative hair dye. US 3,861,868 describes an oxidation dye composition comprising arginine or a protein or polypeptide having a high arginine content, and theorises that the arginine or proteins enhance the penetration of the dye precursors into the hair shaft, thereby stabilizing the dye molecules formed by oxidation. In the above case the arginine or proteins are an integral component of the dye composition itself. In contrast, the present invention provides a method in which the selected organic amino compounds are incorporated into a conventional hair treatment composition such as a shampoo or conditioner to be applied in a separate stage to the oxidative composition. Advantageously, such a shampoo or conditioner can be applied repeatedly to give a beneficial progressive build-up of the colour protection effect, independently of the oxidative composition, for which repeated use would be damaging to the hair. Summary of the Invention The present invention provides a method for reducing colour loss from hair treated with an oxidative composition, such as an oxidative hair dye, the method comprising the step of contacting the hair, either prior to or after treatment of the hair with the oxidative composition, with a colour protective composition comprising an organic amino compound selected from: (i) basic amino acids; (ii) urea; (iii) guanidine; (iv) salts and/or derivatives of any of (i) to (iii) ; (v) mixtures of any of (i) to (iv) . Detailed Description of the Invention According to the method of the present invention, hair is contacted with a colour protective composition comprising certain selected organic amino compounds as described above, either prior to, or after treatment of the hair with an oxidative composition. Preferably the colour protective composition is applied after treatment of the hair with the oxidative composition. Oxidative Composition By "treatment with an oxidative composition" is meant contacting the hair with an oxidative composition such as an oxidative hair dye. The composition employed may be formed separately from the hair and then applied. It may also be formed by mixing the separate reactants as they are applied to the hair, for example by mixing the streams from separate aerosol containers as the streams are applied to the hair. It may also be formed by contacting the reactants with the hair to be treated as the reactants are applied to the hair, either concurrently or successively. The term "oxidative dye" includes compounds and mixtures of compounds which can be oxidised under the treatment conditions described above to form hair colourants. It includes, for example, primary intermediates either alone or together with one or more couplers, autoxidative dyes, and melanin forming dyes such as DHI and its analogues. Hydrogen peroxide is the usual oxidising agent employed in conjunction with oxidative dyes. Other oxidizing agents for use in this context include perborates, persulfates and perhalites, particularly periodates. These oxidising agents are generally employed as ammonium salts or as salts of alkali metals. Colour Protective Composition The colour protective composition comprises an organic amino compound selected from: (i) basic amino acids; (ii) urea; (iii) guanidine; (iv) salts and/or derivatives of any of (i) to (iii) ; (v) mixtures of any of (i) to (iv) . Basic Amino Acids Basic amino acids (i) may be selected from lysine, arginine and histidine and mixtures thereof. These amino acids are hydrophilic due to their polar side chains. Lysine and arginine are positively charged at neutral pH, whereas histidine can be uncharged or positively charged depending on its local environment. Arginine is the most preferred amino acid (i) in the method according to the invention. Alternatively, proteins, polypeptides or other natural extracts having a high basic amino acid content can be used. For example, proteins having a major proportion of arginine units (in the range from about 50 to about 90%, by weight, of the total protein) in their structures are members of that class of proteins known as protamines. The protamine proteins are characterised by having: (a) a low molecular weight, in the range of about 5,000; (b) a high isoelectric point, in the pH range of about 10 to 12; and (c) a high arginine content, in the range from about 50 to about 90%, by weight of the total protein. Suitable examples are described in US 3,997,659. Proteins of high basic amino acid content as described above can be subjected to acid or base hydrolysis to yield polypeptides which also have a high basic amino acid content. Examples of suitable polypeptides are also described in US 3,997,659, being protamine-derived polypeptides having a molecular weight below about 5,000, a basic pH (10-12), and an arginine content of about 50%, or greater, by weight of the total polypeptide. Not only may naturally occurring proteins be used, but also synthetic proteins, for example, polylysine and polyarginine, or mixtures thereof. An example of a suitable natural extract which is rich in arginine is aloe vera extract . The basic amino acids and the proteins and polypeptides having a basic amino acid content of 50%, or greater, are often isolated from natural sources in the form of salts and hydrosalts, which are also suitable for use according to the invention. Such salts and hydrosalts are formed by reaction with mineral acids such as hydrochloric acid, phosphoric acid, carbonic acid, sulfuric acid, nitric acid, and the like, or the organic acids such as formic acid, acetic acid, lauric acid, chloroacetic acid and the like. A suitable example is arginine hydrochloride. Guanidine (iii) may also be present as a salts or hydrosalts formed by reaction with mineral or organic acids as described above. A suitable example is guanidine hydrochloride. The most preferred organic amino compounds in the method according to the invention are arginine and urea and their respective salts and/or hydrosalts. Mixtures of any of the above organic amino compounds may also be used. The total amount of organic amino compound may suitably range from 0.01% to 10% by weight based on total weight of the hair treatment composition in which it is employed. Preferably, the amount of organic amino compound ranges from 0.02 to 5% by weight based on total weight, and will ideally range from 0.05% to 2% by weight based on total weight. Product Form Colour protective compositions according to the invention may suitably take the form of shampoos, conditioners, sprays, mousses, gels, cremes or lotions. Preferred forms are shampoos and conditioners. Advantageously, the colour protective composition comprising an organic amino compound for use in the method according to the invention can be formulated as a shampoo and will then accordingly comprise one or more cleansing surfactants which are cosmetically acceptable and suitable for topical application to the hair. Suitable cleansing surfactants, which may be used singularly or in combination, are selected from anionic, amphoteric and zwitterionic surfactants, and mixtures thereof. Examples of anionic surfactants are the alkyl sulphates, alkyl ether sulphates, alkaryl sulphonates, alkanoyl isethionates, alkyl succinates, alkyl sulphosuccinates, N- alkyl sarcosinates, alkyl phosphates, alkyl ether phosphates, alkyl ether carboxylates, and alpha-olefin sulphonates, especially their sodium, magnesium, ammonium and mono-, di- and triethanolamine salts. The alkyl and acyl groups generally contain from 8 to 18 carbon atoms and may be unsaturated. The alkyl ether sulphates, alkyl ether U ) LO t t LΠ o LΠ o LΠ o LΠ Ω φ SD 3 CQ μ- 3 LQ TJ N 0 TJ Φ K rt μ- Φ ω rr 0 rt tr Φ Ω 0 3 J 0 CQ μ- rt μ- 0 3 • H tr Φ 3 0 3 μ- 0 3 μ- Ω surfactant can be included in an amount ranging from 0% to about 5% by weight based on total weight. For example, representative nonionic surfactants include condensation products of aliphatic (Cβ - Cis) primary or secondary linear or branched chain alcohols or phenols with alkylene oxides, usually ethylene oxide and generally having from 6 to 30 ethylene oxide groups. Other representative nonionics include mono- or di-alkyl alkanolamides . Examples include coco mono- or di- ethanolamide and coco mono-isopropanolamide. Further nonionic surfactants which can be included are the alkylpolyglycosides (APGs) . Typically, the APG is one which comprises an alkyl group connected (optionally via a bridging group) to a block of one or more glycosyl groups. Preferred APGs are defined by the following formula: RO - (G)n wherein R is a branched or straight chain alkyl group which may be saturated or unsaturated and G is a saccharide group. R may suitably represent a mean alkyl chain length of from about Cs to about C20. Preferably R represents a mean alkyl chain length of from about Cs to about C12. Most preferably the value of R lies between about 9.5 and about 10.5. G may be selected from Cs or Ce monosaccharide residues, and is preferably a glucoside. G may be selected from the group comprising glucose, xylose, lactose, fructose, mannose and derivatives thereof. Preferably G is glucose. The degree of polymerisation, n, may have a value of from about 1 to about 10 or more. Preferably, the value of n lies in the range of from about 1.1 to about 2. Most preferably the value of n lies in the range of from about 1.3 to about 1.5. Suitable alkyl polyglycosides are commercially available and include for example those materials identified as: Oramix NS10 ex Seppic; Plantaren 1200 and Plantaren 2000 ex Henkel . Likewise shampoos for use according to the invention can include other emulsifiers, conditioning agents, inorganic salts, humectants and similar materials to provide the composition with desirable aesthetic or physical properties. Representative conditioning agents include silicones. Silicones are particularly preferred conditioning agents for hair. Representative silicones include volatile and nonvolatile silicones, such as for example polyalkylsiloxanes (optionally end-capped with one or more hydroxyl groups) , polyalkylaryl siloxanes, siloxane gums and resins, cyclomethicones, aminofunctional silicones, quaternary silicones and mixtures thereof. Preferred silicones include polydimethylsiloxanes (of CTFA designation dimethicone) , siloxane gums, aminofunctional silicones (of CTFA designation amodimethicone) and hydroxylated polydimethylsiloxanes (of CTFA designation dimethiconol) . Various methods of making emulsions of particles of silicones are available and are well known and documented in the art . Suitable silicone emulsions are commercially available in a pre-emulsified form. This is particularly preferred since the pre- formed emulsion can be incorporated into the shampoo composition by simple mixing. Examples of suitable pre- formed emulsions include emulsions DC2-1310, DC2-1865, DC2-1870, DC2-1766 and DC2-1784, available from Dow Corning. These are emulsions of dimethiconol. Siloxane gums are also available in a pre- emulsified form, which is advantageous for ease of formulation. A preferred example is the material available from Dow Corning as DC X2-1787, which is an emulsion of cross-linked dimethiconol gum. The amount of silicone incorporated into compositions for use according to the invention depends on the level of conditioning desired and the material used. A preferred amount is from 0.01 to about 10% by weight of the total composition although these limits are not absolute. The lower limit is determined by the minimum level to achieve conditioning and the upper limit by the maximum level to avoid making the hair and/or skin unacceptably greasy. We have found that an amount of silicone of from 0.5 to 1.5% by weight of the total composition, is a particularly suitable level . A further preferred class of conditioning agents are per- alk(en)yl hydrocarbon materials, used to enhance the body, volume and stylability of hair. EP 567 326 and EP 498 119 describe suitable peralk(en)yl hydrocarbon materials for imparting stylability and enhanced body to hair. Preferred materials are polyisobutylene materials available from Presperse, Inc. under the PERMETHYL trade name. The amount of per-alk (en) yl hydrocarbon material incorporated into compositions for use according to the invention depends on the level of body and volume enhancement desired and the specific material used. A preferred amount is from 0.01 to about 10% by weight of the total composition although these limits are not absolute. The lower limit is determined by the minimum level to achieve the body and volume enhancing effect and the upper limit by the maximum level to avoid making the hair unacceptably stiff. We have found that an amount of per- alk (en) yl hydrocarbon material of from 0.5 to 2% by weight of the total composition is a particularly suitable level. Shampoo compositions for use according to the invention may also include a polymeric cationic conditioning compound that is substantive to the hair and imparts conditioning properties to the hair. The polymeric cationic conditioning compound will generally be present at levels of from 0.01 to 5%, preferably from about 0.05 to 1%, more preferably from about 0.08% to about 0.5% by weight. Synthetic or naturally derived polymers having a quaternised nitrogen atom are useful . The molecular weight of the polymer will generally be between 5 000 and 10 000 000, typically at least 10 000 and preferably in the range 100 000 to about 2 000 000. Representative synthetic quaternised polymers include, for example: cationic copolymers of 1-vinyl-2 -pyrrolidine and 1- vinyl-3 -methyl-imidazolium salt (e.g., Chloride salt) (referred to in the industry by the Cosmetic, Toiletry, and Fragrance Association, "CTFA". as Polyquaternium-16) ; copolymers of l-vinyl-2-pyrrolidine and dimethylaminoethyl methacrylate (referred to in the industry by CTFA as Polyquaternium-11) ; cationic diallyl quaternary ammonium- containing polymers including, for example, dimethyldiallylammonium chloride homopolymer (referred to in the industry (CTFA) as Polyquaternium 6) ; mineral acid salts of amino-alkyl esters of homo-and co-polymers of unsaturated carboxylic acids having from 3 to 5 carbon atoms, as described in U.S. Patent 4,009,256; and cationic polyacrylamides as described in W095/22311. Representative naturally-derived quaternised polymers include quaternised cellulosic compounds and cationic guar gum derivatives, such as guar hydroxypropyltrimonium chloride. Examples are JAGUAR C-13S, JAGUAR C-15, and JAGUAR-C17, commercially available from Meyhall in their JAGUAR trademark series . Compositions for use in accordance with the invention may also be formulated as a hair conditioner for the treatment of hair (typically after shampooing) and subsequent rinsing. Such formulations will then accordingly comprise one or more conditioning surfactants which are cosmetically acceptable and suitable for topical application to the hair. Suitable conditioning surfactants are selected from cationic surfactants, used singly or in admixture. Examples include quaternary ammonium hydroxides or salts thereof, e.g chlorides . Suitable cationic surfactants include cetyltrimethylammonium chloride, behenyltrimethylammonium chloride, cetylpyridinium chloride, tetramethylammonium chloride, tetraethylammonium chloride, octyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octyldimethylbenzylammonium chloride, decyldimethylbenzylarrtmonium chloride, stearyldimethylbenzylammonium chloride, LO LO tO t μ> in O LΠ o in O in - .. μ> rt 0 .. CO ^ 0 TJ rt μ- 3 SD ^ Hi μ 0 3 *• H rt O μ> • • J • Conditioners for use according to the invention can include other emulsifiers, conditioning agents, inorganic salts, humectants and similar materials to provide the composition with desirable aesthetic or physical properties. Silicones, as described above for shampoo compositions, are particularly preferred conditioning agents for hair. As further optional components for inclusion in shampoo or conditioner compositions for use according to the invention, in addition to water, may be mentioned the following conventional adjunct materials known for use in cosmetic compositions: suspending agents, thickeners, pearlescing agents, opacifiers, salts, perfumes, buffering agents, colouring agents, emollients, moisturisers, foam stabilisers, sunscreen materials, antimicrobial agents, preservatives, antioxidants, natural oils and extracts, propellants. The invention will now be further illustrated by the following, non-limiting Examples. EXAMPLES Examples 1 to 3 The following formulations were prepared. Examples 1 to 3 are Examples according to the invention. Comp.Ex. A and Comp.Ex. B are comparative examples. The above formulations were tested as follows. For each test formulation, a hair switch was split into two, and one half twice bleached. The other half was twice bleached and coloured permanently. LAB chroma values were measured on a Hunterlab and the difference in coloured ΔE was calculated between bleached and bleached and coloured half switches. The switches were washed for up to 30 minutes in the test formulation and the percentage of decrease of colour difference between the coloured half switch and non coloured half switch due to colour loss was calculated. Four replicates were used per test formulation. All of the test switches treated with the formulations of Examples 1 to 3 showed a perceptible decrease in colour loss after washing, compared with those treated with either of the Comp. Ex.A or Comp. Ex.B formulations.

Claims: CLAIMS 1. A method for reducing colour loss from hair treated with an oxidative composition, such as an oxidative hair dye, the method comprising the step of contacting the hair, either prior to or after treatment of the hair with the oxidative composition, with a colour protective composition comprising an organic amino compound selected from: (i) basic amino acids; (ii) urea; (iii) guanidine; (iv) salts and/or derivatives of any of (i) to (iii) ; (v) mixtures of any of (i) to (iv) . 2. A method according to claim 1, in which the organic amino compound is selected from arginine, urea and mixtures thereof . 3. A method according to claim 1 or 2 , in which the amount of organic amino compound ranges from 0.01% to 10% by weight based on total weight. 4. A method according to any of claims 1 to 3 , in which the colour protective composition is formulated as a shampoo composition. 5. A method according to any of claims 1 to 4 , in which the colour protective composition is formulated as a hair conditioner.

Inventors: CORNWELL PAUL ALFRED, NOEL NATHALIE, SKINNER RICHARD, CORNWELL, PAUL, ALFRED, NOEL, NATHALIE, SKINNER, RICHARD
Applicants: LEVER HINDUSTAN LTD, UNILEVER NV, UNILEVER PLC, HINDUSTAN LEVER LIMITED
Application year: 2000
Main classification: A61K7
IPC codes: A61K8, A61Q5