WO2014095318A2

WO2014095318A2 - Method of preventing hair fibre damage

Info

Publication number: WO2014095318A2
Application number: PCT/EP2013/075202
Authority: WO
Inventors: Ranjit Kaur Bhogal; Eleanor Yveline Margaret BONNIST; John Casey; Eleanor Margaret D'agostino; Paul David Austin PUDNEY
Original assignee: Unilever Plc; Unilever N.V.; Conopco, Inc., D/B/A Unilever
Priority date: 2012-12-21
Filing date: 2013-12-02
Publication date: 2014-06-26
Also published as: WO2014095318A3

Abstract

Hair can be damaged in a number of ways including exposure to heat, bleaching, use of shampoos and styling products, brushing and combing, and exposure to the environment, for example ultra-violet light. Existing treatments designed to repair damaged hair make use of surface active materials that mask the problem rather than actually repairing the hair. These materials modify fibre feel by changing consumer perceivable fibre sensory cues such as smoothness, may change some measureable physical properties such as hydrophobicity and hydrophilicity, but do not change other physical characteristics such as fibre stiffness, strength or structural integrity. The invention relates to a method of preventing hair fibre damage using flavonoids, hydrogen peroxide and a peroxidase enzyme.

Description

METHOD OF PREVENTING HAIR FIBRE DAMAGE

The invention relates to a method of preventing hair fibre damage using flavonoids, hydrogen peroxide and a peroxidase enzyme.

Hair can be damaged in a number of ways including exposure to heat, bleaching, use of shampoos and styling products, brushing and combing, and exposure to the environment, for example ultra-violet light. Existing treatments designed to repair damaged hair make use of surface active materials that mask the problem rather than actually repairing the hair. These materials modify fibre feel by changing consumer perceivable fibre sensory cues such as smoothness, may change some measureable physical properties such as hydrophobicity and hydrophilicity, but do not change other physical characteristics such as fibre stiffness, strength or structural integrity.

US 2004/0261 198 (Henkel Corporation) discloses a method for modifying keratin fibres, in particular for restructuring and finishing by positively influencing the fibre properties, in particular the strength, porosity, elasticity, colour retention and volume of the fibres, by polymerising suitable polymerisable substrates at the fibre by using a polyphenol oxidase. The compositions should be free of peroxides or hydroperoxides. Swelling of the hair in the wet state is described as a measure of hair damage. Suitable substrates are phenolic compounds substituted by 1 to 5 groups, an example of which includes catechin; aromatic amines; enolic ompounds; and enaminic compounds. The invention was exemplified with a combination of green tea powder, a polyphenol oxidase from the fungus Myceliophtora, and methyl syringate as mediator, at pH 6.5-7.5 and at 32 °C on bleached hair. Significant increases in the stress and work values in the plastic range for wet individual hair fibres were observed demonstrating restructuring of the bleached hair by the green tea and the laccase enzyme.

WO 2010/130526 (Henkel AG & Co. KGAA) discloses a cosmetic hair treatment agent free from hydrogen peroxide, the agent comprising, in a cosmetic carrier, a surface-active agent and an acetylpyridinium derivative of a given formula for improving the general condition of hair fibres and increasing the elasticity of the hair. The agent may additionally include a plant extract. Green tea is disclosed as an example of such a plant extract.

WO 2010/130510 (Henkel AG & Co. KGAA) discloses a cosmetic hair shaping product comprising, in a cosmetic carrier, a hair strengthening and/or film-forming polymer, and an acetylpyridinium derivative of a given formula for reducing hair damage in the interior of the hair and for increasing the elasticity of the hair. The product may additionally include a plant extract. Green tea is disclosed as an example of such a plant extract.

SUMMARY OF THE INVENTION

This invention is based on the observation by the inventors that pre-treatment of hairs with catechin/horseradish peroxidase/hydrogen peroxide before bleaching reduces the amount of sulphur oxidation upon bleaching.

Thus in a first aspect of the invention, a method of preventing hair fibre damage is provided, the method comprising the step of applying a hair composition to unbleached hair fibres, the hair composition comprising:

(a) A flavonoid or a derivative thereof; and either

(b) A peroxidase in combination with a hydrogen peroxide generator or hydrogen peroxide; or

(c) A laccase;

wherein the composition has a pH of 3 to 9, preferably 4.5 to 7, more preferably less than or equal to 6;

preferably wherein the hair fibre damage is caused by bleaching.

SUMMARY OF THE FIGURES

The invention is exemplified with reference to the following figures in which: Figure 1 shows the ratio of the Raman spectroscopy S-O peak (1020-1070 cm^"1) to the phenylalanine peak (990-1016 cm^"1) versus depth into hair fibre (μιτι); and

Figure 2 shows the ratio of the Raman spectroscopy S-S peak (480-549 cm^"1) to the phenylalanine peak (990-1016 cm^"1) versus depth into hair fibre (μιτι); DETAILED DESCRIPTION OF THE INVENTION

A method of preventing hair fibre damage is provided, the method comprising the step of applying a hair composition to unbleached hair fibres, the hair composition comprising:

(a) A flavonoid or a derivative thereof; and either

(c) A laccase;

preferably wherein the hair fibre damage is caused by bleaching.

The flavonoid may be selected from the group consisting of flavones, isoflavones, flavans, isoflavans, flavanones, flavonols, flavan-3-ols, dihydroflavonol, flavanonols, anthocyanidins, proanthocyanidins, auron, chalcone, dihydrochalcone, flavonolignans, and derivatives thereof. Preferably the flavone is selected from the group consisting of apigenin, luteolin and chrysin; the isoflavone is selected from the group consisting of daidzein, genistein and formononetin; the flavan is 4'-hydroxy- 5,6-dimethoxyflavan; the isoflavan is glabridin or licoricidin; the flavanone is naringenin or eriodictyol; the flavonol is selected from the group consisting of myricetin, kaempferol, gossypetin and quercetin; the flavan-3-ol is selected from the group consisting of catechin, theaflavin, gallocatechin, catechin gallate, gallocatechin gallate, epicatechin, epigallocatechin, epigallocatechin gallate and epigallocatechin gallate; the dihydroflavonol is taxifolin or aromadendrin; the anthocyanidin is selected from the group consisting of cyanidin, delphinidin, pelargonidin and malvidin; the aurone is sulphuretin; the chalcone is 2'-hydroxy-4- methoxy-chalcone; the dihydrochalcone is phloretin or phloridzin and the flavonolignan is silibinin or silichristin.

In one particular embodiment, the flavonoid is selected from the group consisting of silibinin, silandrin, 3,4-dihydroxyflavone, hesperidin (glycoside), naringin (naringenin glycoside), amentoflavone, rutin, eriodictyol-7-O-glucoside, quercitrin, kaempferol, pinostrobin and biochanin A. In another particular embodiment, the flavonoid is selected from the group consisting of (+)-catechin, myricetin, gossypetin, luteolin and apigenin and naringenin. The peroxidase is preferably a non-animal haem peroxidase from class II (fungi) or class III (plants and algae). Examples include those obtained from the group consisting of Arabidopsis thaliana, horse radish, barley, peanut soybean, tobacco, and turnip (plants), Chlorophyta spirogyra (green algae), Arthromyces ramosus and Corprinus cinereus (fungi).

The laccase is preferably selected from a fungal or a plant source such as those from the group consisting of the Aspergillus, Botrytis, Ceriporiopsis, Cerrena, Chaetomium, Coprinus, Coriolus, Neurospora, Panus, Phanerochaete, Pleurotus, Polyporus, Pycnoporus and Trametes genera, and Rhus vernicifera.

The hair composition preferably comprises 0.01 - 10, preferably 0.1 - 5 % w/w flavonoid; 0.0001 - 3 preferably 0.001 - 1 , most preferably 0.01 - 1 % w/w hydrogen peroxide; and 0.0001 - 5, preferably 0.001 - 1 % w/w peroxidase or laccase. When using a hydrogen peroxide generator, this comprises a hydrogen peroxide generating oxidase, a substrate and oxygen. The hydrogen peroxide generating oxidase may be selected from the group consisting of (S)-2-hydroxy acid oxidase, D- galactose oxidase, glucose oxidase, coniferyl alcohol oxidase, glycolate oxidase, hexose oxidase, oxalate oxidase, amino acid oxidase and L-galactonolactone oxidase and the respective substrate is selected from the group consisting of (S)-2- hydroxy acid, D-galactose, glucose, coniferyl alcohol, · -hydroxy acids, D-glucose, oxalic acid, amino acid and L-galactono-1 ,4-lactone. Specifically the following combinations may be used: (S)-2-hydroxy acid with (S)-2-hydroxy acid oxidase; D- galactose with D-galactose oxidase; glucose with glucose oxidase; coniferyl alcohol with coniferyl alcohol oxidase; · -hydroxy acids with glycolate oxidase; D-glucose with hexose oxidase; oxalic acid with oxalate oxidase; and L-galactono-1 , 4-lactone with L-galactonolactone oxidase; amino acid oxidase with amino acids; all in the presence of oxygen. The hair composition may comprise 0.0001 - 5, preferably 0.001 - 1 % w/w hydrogen peroxide generating oxidase; and 0.01 - 10 preferably 0.1 - 5 % w/w substrate. The hair composition may take the form of a shampoo or hair conditioning composition, or a 2-in-1 conditioning shampoo composition.

Shampoo Compositions

Shampoo compositions will nearly always comprise a cleansing surfactant component in an aqueous base.

Cleansing Surfactant

The cleansing surfactant may consist of a single surfactant, usually an anionic surfactant (to provide foam) such as sodium lauryl ether sulphate, or more commonly a mixture of sodium lauryl ether sulphate with a co-surfactant to provide mildness. The most preferred co-surfactant is cocoamidopropyl betaine.

The total amount of surfactant (including any co-surfactant, and/or any emulsifier) in a shampoo composition may be from 1 to 50., preferably from 2 to 40, more preferably from 10 to 25 % w/w. Compositions comprising more than 25 % w/w cleansing surfactant are commonly considered concentrated shampoos.

Examples of suitable anionic cleansing surfactants are the alkyl sulphates, alkyl ether sulphates, alkaryl sulphonates, alkanoyl isethionates, alkyl succinates, alkyl sulphosuccinates, alkyl ether sulphosuccinates, N-alkyl sarcosinates, alkyl phosphates, alkyl ether phosphates, and alkyl ether carboxylic acids and salts thereof, especially their sodium, magnesium, ammonium and mono-, di- and triethanolamine salts. The alkyl and acyl groups generally contain from 8 to 18, preferably from 10 to 16 carbon atoms and may be unsaturated. The alkyl ether sulphates, alkyl ether sulphosuccinates, alkyl ether phosphates and alkyl ether carboxylic acids and salts thereof may contain from 1 to 20 ethylene oxide or propylene oxide units per molecule. Typical anionic cleansing surfactants for use in shampoo compositions of the invention include sodium oleyl succinate, ammonium lauryl sulphosuccinate, sodium lauryl sulphate, sodium lauryl ether sulphate, sodium lauryl ether sulphosuccinate, ammonium lauryl sulphate, ammonium lauryl ether sulphate, sodium dodecylbenzene sulphonate, triethanolamine dodecylbenzene sulphonate, sodium cocoyl isethionate, sodium lauryl isethionate, lauryl ether carboxylic acid and sodium N-lauryl sarcosinate.

Preferred anionic surfactants are the alkyl sulfates and alkyl ether sulfates. These materials have the respective formulae R20S0₃M and R10(C₂H₄0)xS0₃M, wherein R2 is alkyl or alkenyl of from 8 to 18 carbon atoms, x is an integer having a value of from about 1 to about 10, and M is a cation such as ammonium, alkanolamines, such as triethanolamine, monovalent metals, such as sodium and potassium, and polyvalent metal cations, such as magnesium, and calcium. Most preferably R2 has 12 to 14 carbon atoms, in a linear rather than branched chain.

Preferred anionic cleansing surfactants are selected from sodium lauryl sulphate and sodium lauryl ether sulphate(n)EO, (where n is from 1 to 3); more preferably sodium lauryl ether sulphate(n)EO, (where n is from 1 to 3); most preferably sodium lauryl ether sulphate(n)EO where n=1 .

Preferably the level of alkyl ether sulphate is from 0.5 to 25, more preferably from 3 to 18, most preferably from 6 to 15 % w/w of the composition. The total amount of anionic cleansing surfactant in shampoo compositions of the invention generally ranges from 0.5 to 45, more preferably from 1 .5 to 20 % w/w of the composition.

Nonionic Surfactant

Shampoo compositions of the invention may contain non-ionic surfactant. Most preferably non-ionic surfactants are present in the range 0 to 5 % w/w of the composition. Nonionic surfactants that can be included in shampoo compositions of the invention include condensation products of aliphatic (C8 - C18) 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. Alkyl ethoxylates are particularly preferred. Most preferred are alkyl ethoxylates having the formula R- (OCH₂CH₂)nOH, where R is an alkyl chain of C12 to C1 5, and n is 5 to 9.

Other suitable nonionic surfactants include mono- or di-alkyl alkanolamides. Examples include coco mono- or di-ethanolamide and coco mono-isopropanolamide.

Further nonionic surfactants which can be included in shampoo compositions of the invention are the alkyl polyglycosides (APGs). Typically, 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 represent a mean alkyl chain length of from about C5 to about C20. Preferably R represents a mean alkyl chain length of from about C8 to about C1 2. Most preferably the value of R lies between about 9.5 and about 1 0.5. G may be selected from C5 or C6 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 1 0 or more, preferably a value of from about 1 .1 to about 2, most preferably a value of from about 1 .3 to about 1 .5. Suitable alkyl polyglycosides for use in the invention are commercially available and include for example those materials identified as: Oramix NS1 0 ex Seppic; Plantaren 1200 and Plantaren 2000 ex Henkel.

Other sugar-derived nonionic surfactants which can be included in compositions of the invention include the C1 0-C1 8 N-alkyl (CI-C6) polyhydroxy fatty acid amides, such as the C1 2-C18 N-methyl glucamides, as described for example in WO 92/061 54 and US 5 1 94 639, and the N-alkoxy polyhydroxy fatty acid amides, such as C1 0-C18 N-(3-methoxypropyl) glucamide. Amphoteric/zwitterionic Surfactant

Amphoteric or zwitterionic surfactant can be included in an amount ranging from 0.5 to about 8, preferably from 1 to 4 % w/w of the shampoo compositions of the invention.

Examples of amphoteric or zwitterionic surfactants include alkyl amine oxides, alkyl betaines, alkyl amidopropyl betaines, alkyl sulphobetaines (sultaines), alkyl glycinates, alkyl carboxyglycinates, alkyl amphoacetates, alkyl amphopropionates, alkylamphoglycinates, alkyl amidopropyl hydroxysultaines, acyl taurates and acyl glutamates, wherein the alkyl and acyl groups have from 8 to 19 carbon atoms. Typical amphoteric and zwitterionic surfactants for use in shampoos of the invention include lauryl amine oxide, cocodimethyl sulphopropyl betaine, lauryl betaine, cocamidopropyl betaine and sodium cocoamphoacetate. A particularly preferred amphoteric or zwitterionic surfactant is cocamidopropyl betaine.

Mixtures of any of the foregoing amphoteric or zwitterionic surfactants may also be suitable. Preferred mixtures are those of cocamidopropyl betaine with further amphoteric or zwitterionic surfactants as described above. A preferred further amphoteric or zwitterionic surfactant is sodium cocoamphoacetate.

Suspending agents

Preferably an aqueous shampoo composition of the invention further comprises a suspending agent. Suitable suspending agents are selected from polyacrylic acids, cross-linked polymers of acrylic acid, copolymers of acrylic acid with a hydrophobic monomer, copolymers of carboxylic acid-containing monomers and acrylic esters, cross-linked copolymers of acrylic acid and acrylate esters, heteropolysaccharide gums and crystalline long chain acyl derivatives. The long chain acyl derivative is desirably selected from ethylene glycol stearate, alkanolamides of fatty acids having from 16 to 22 carbon atoms and mixtures thereof. Ethylene glycol distearate and polyethylene glycol 3 distearate are preferred long chain acyl derivatives, since these impart pearlescence to the composition. Polyacrylic acid is available commercially as Carbopol 420, Carbopol 488 or Carbopol 493. Polymers of acrylic acid cross- linked with a polyfunctional agent may also be used; they are available commercially as Carbopol 910, Carbopol 934, Carbopol 941 and Carbopol 980. An example of a suitable copolymer of a carboxylic acid containing monomer and acrylic acid esters is Carbopol 1342. Carbopol 980 is the commonly used suspending agent though there is a growing desire to find an alternative. All Carbopol (trademark) materials are available from Goodrich.

Suitable cross-linked polymers of acrylic acid and acrylate esters are Pemulen TR1 or Pemulen TR2. A suitable heteropolysaccharide gum is xanthan gum, for example that available as Kelzan mu.

Mixtures of any of the above suspending agents may be used. Preferred is a mixture of cross-linked polymer of acrylic acid and crystalline long chain acyl derivative. Suspending agent will generally be present in a shampoo composition of the invention at levels of from 0.1 to 10, preferably from 0.5 to 6, more preferably from 0.9 to 4 % w/w of the composition. Generally such suspending agents are present at around 2 % w/w of the composition. Water

Shampoo compositions of the invention are generally aqueous, i.e. they have water or an aqueous solution or a lyotropic liquid crystalline phase as their major component. Suitably, the composition will comprise from 50 to 98, preferably from 60 to 90 % w/w of the composition.

Typically, shampoo compositions have a pH of around 5.5. Optional Ingredients

The shampoo compositions of the invention might also contain the following optional ingredients: conditioning agents;

Conditioning Agents

Conditioning actives are often included in shampoo compositions. These are sometimes called ^!2-in-1 ' formulations. Conditioning actives fall into three classes: silicones (and cationic deposition polymers to assist in silicone deposition) cationic surfactants

non-silicone oils Where silicones are included, the composition is likely to also contain a cationic deposition polymer for enhancing deposition of the silicone. Further, a silicone- containing composition is likely to be lamellar as opposed to isotropic. Isotropic compositions do not deposit silicone effectively. Silicones

The shampoo compositions of the invention can contain emulsified droplets of a silicone conditioning agent, for enhancing conditioning performance.

Suitable silicones include polydiorganosiloxanes, in particular polydimethylsiloxanes which have the CTFA designation dimethicone. Also suitable for use compositions of the invention (particularly shampoos and conditioners) are polydimethyl siloxanes having hydroxyl end groups, which have the CTFA designation dimethiconol. Also suitable for use in compositions of the invention are silicone gums having a slight degree of cross-linking, as are described for example in WO 96/31 188.

Examples of suitable pre-formed emulsions include Xiameter MEM 1785 and microemulsion DC2-1865 available from Dow Corning. These are emulsions /microemulsions of dimethiconol. Cross-linked silicone gums are also available in a pre-emulsified form, which is advantageous for ease of formulation.

A further preferred class of silicones for inclusion in shampoos and conditioners of the invention are amino functional silicones. By "amino functional silicone" is meant a silicone containing at least one primary, secondary or tertiary amine group, or a quaternary ammonium group. Examples of suitable amino functional silicones include: polysiloxanes having the CTFA designation "amodimethicone".

Specific examples of amino functional silicones suitable for use in the invention are the aminosilicone oils DC2-8220, DC2-8166 and DC2-8566 (all ex Dow Corning). The most commonly used amino silicone is sourced from Dow Corning and is coded DC7134. Pre-formed emulsions of amino functional silicone are also available from suppliers of silicone oils such as Dow Corning and General Electric. Specific examples include DC939 Cationic Emulsion and the non-ionic emulsions DC2-7224, DC2-8467, DC2-8177 and DC2-8154 (all ex Dow Corning).

Suitable quaternary silicone polymers are described in EP-A-0 530 974. A preferred quaternary silicone polymer is K3474, ex Goldschmidt. With some shampoos it is preferred to use a combination of amino and non amino functional silicones.

Emulsified silicones for use in the shampoo compositions of the invention will typically have an average silicone droplet size in the composition of less than 30, preferably less than 20, more preferably less than 10 micron, ideally from 0.01 to 1 micron. Silicone emulsions having an average silicone droplet size of about 0.15 micron are generally termed microemulsions.

Emulsified silicones for use in the conditioner compositions of the invention will typically have a size in the composition of less than 30, preferably less than 20, more preferably less than 15. Preferably the average silicone droplet is greater than 0.5 micron, more preferably greater than 1 micron, ideally from 2 to 8 micron.

Silicone particle size may be measured by means of a laser light scattering technique, for example using a 2600D Particle Sizer from Malvern Instruments.

The viscosity of the emulsified silicone itself (not the emulsion or the final hair conditioning composition) is typically at least 10,000, preferably at least 60,000, most preferably at least 500,000, ideally at least 1 ,000,000 est at 25 °C. Preferably the viscosity does not exceed 10⁹ est at 25 °C for ease of formulation.

The total amount of silicone is preferably from 0.01 to 10, more preferably from 0.1 to 5, most preferably 0.5 to 3 % w/w of the composition of the invention. Also suitable are emulsions of amino functional silicone oils with non ionic and/or cationic surfactant.

Cationic deposition polymers are used to deposit the silicone droplets to the hair surface and hence enhance performance.

Suitable cationic polymers may be homopolymers which are cationically substituted or may be formed from two or more types of monomers. The weight average (Mw) molecular weight of the polymers will generally be between 100 000 and 2 million daltons. The polymers will have cationic nitrogen containing groups such as quaternary ammonium or protonated amino groups, or a mixture thereof. If the molecular weight of the polymer is too low, then the conditioning effect is poor. If too high, then there may be problems of high extensional viscosity leading to stringiness of the composition when it is poured.

The cationic nitrogen-containing group will generally be present as a substituent on a fraction of the total monomer units of the cationic polymer. Thus when the polymer is not a homopolymer it can contain spacer non-cationic monomer units. Such polymers are described in the CTFA Cosmetic Ingredient Directory. The ratio of the cationic to non-cationic monomer units is selected to give polymers having a cationic charge density in the required range, which is generally from 0.2 to 3.0 meq/gm. The cationic charge density of the polymer is suitably determined via the Kjeldahl method as described in the US Pharmacopoeia under chemical tests for nitrogen determination.

Suitable cationic polymers include, for example, copolymers of vinyl monomers having cationic amine or quaternary ammonium functionalities with water soluble spacer monomers such as (meth)acrylamide, alkyl and dialkyl (meth)acrylamides, alkyl (meth)acrylate, vinyl caprolactone and vinyl pyrrolidine. The alkyl and dialkyl substituted monomers preferably have C1 -C7 alkyl groups, more preferably C1 -3 alkyl groups. Other suitable spacers include vinyl esters, vinyl alcohol, maleic anhydride, propylene glycol and ethylene glycol. The cationic amines can be primary, secondary or tertiary amines, depending upon the particular species and the pH of the composition. In general secondary and tertiary amines, especially tertiary, are preferred. Amine substituted vinyl monomers and amines can be polymerized in the amine form and then converted to ammonium by quaternization.

The cationic polymers can comprise mixtures of monomer units derived from amine- and/or quaternary ammonium-substituted monomer and/or compatible spacer monomers.

Suitable cationic polymers include, for example:

• cationic diallyl quaternary ammonium-containing polymers including, for example, dimethyldiallylammonium chloride homopolymer and copolymers of acrylamide and dimethyldiallylammonium chloride, referred to in the industry

(CTFA) as Polyquaternium 6 and Polyquaternium 7, respectively;

• 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 US 4 009 256); and

· cationic polyacrylamides (as described in W095/2231 1 ).

Other cationic polymers that can be used include cationic polysaccharide polymers, such as cationic cellulose derivatives, cationic starch derivatives, and cationic guar gum derivatives.

Cationic polysaccharide polymers suitable for use in compositions of the invention include monomers of the formula A-O-[R-N+(R1 )(R2)(R3)X-] wherein A is an anhydroglucose residual group, such as a starch or cellulose anhydroglucose residual; R is an alkylene, oxyalkylene, polyoxyalkylene, or hydroxyalkylene group, or combination thereof; R1 , R2 and R3 independently represent alkyl, aryl, alkylaryl, arylalkyi, alkoxyalkyi, or alkoxyaryl groups, each group containing up to about 18 carbon atoms; the total number of carbon atoms for each cationic moiety (i.e., the sum of carbon atoms in R1 , R2 and R3) is preferably about 20 or less; and X is an anionic counterion.

Another type of cationic cellulose includes the polymeric quaternary ammonium salts of hydroxyethyl cellulose reacted with lauryl dimethyl ammonium-substituted epoxide, referred to in the industry (CTFA) as Polyquaternium 24. These materials are available from the Amerchol Corporation, for instance under the tradename Polymer LM-200. Other suitable cationic polysaccharide polymers include quaternary nitrogen- containing cellulose ethers (e.g. as described in US 3 962 418), and copolymers of etherified cellulose and starch (e.g. as described in US 3 958 581 ).

A particularly suitable type of cationic polysaccharide polymer that can be used is a cationic guar gum derivative, such as guar hydroxypropyltrimethylammonium chloride (commercially available from Rhodia in their JAGUAR trademark series). Examples of such materials are JAGUAR C13S, JAGUAR C14, JAGUAR C15, JAGUAR C17 and JAGUAR C1 6 Jaguar CHT and JAGUAR C162. Mixtures of any of the above cationic polymers may be used.

Cationic polymer will generally be present in a shampoo composition of the invention at levels of from 0.01 to 5, preferably from 0.05 to 1 , more preferably from 0.08 to 0.5 % w/w of the weight of the compositions of the invention.

Cationic Surfactants

Cationic surfactants may be used in 2-in-1 shampoos to provide a conditioning benefit. However, since a shampoo composition is likely to also comprise anionic cleansing surfactants, the use of cationic surfactants is limited to compositions where the cationic surfactant is separated from the anionic phase by way of a stable conditioning gel phase made separately from the rest of the formulation and then incorporated afterwards. Non-silicone Oils

These are typically hydrocarbon oils or fatty alcohols. A fatty alcohol is nearly always included in a conditioning composition and often included in 2-in-1 shampoos. Cetearyl alcohol is one of the preferred examples.

Fibre Actives

Fibre actives are provided to repair or coat the hair fibres. Examples are trehalose (a disaccharide), adipic acid (dicarboxylic acid) and gluconolactone. Anti-dandruff Actives

There are two classes of anti-dandruff active: the azoles and the pyrithiones, both are active against the target fungi malassezia spp. The azoles include ketoconazole and climbazole which are fat soluble actives. The pyrithiones include zinc pyrithione (ZPT) which is insoluble and delivered as a particle to the scalp.

Preferably, the antidandruff active is present at from 0.01 to 5, more preferably from

0.1 to 2.5 % w/w of the composition of the invention.

Hair Conditioning Compositions

The compositions of the invention may also be hair conditioning compositions (also known as conditioners). A conditioner which is to be used after a shampoo is known as a 'system conditioner' whereas one which is included in a shampoo composition is known as a ^!2-in-1 '. Hair conditioning compositions may also be left on the head,

1. e. not rinsed off after application. These are known as Leave-on-Treatments (LOTs) as opposed to Rinse-off-Treatments (ROTs).

The main ingredients in a system conditioner are the conditioning actives described above, the main actives being a cationic surfactant (e.g. behenyltrimmonium chloride), a silicone conditioning agent (e.g. aminosilicone (DC 7134)) and a non- silicone oil, usually a fatty alcohol (e.g. cetearyl alcohol).

Anti-dandruff actives may also be included in hair conditioning compositions of the invention. Cationic Surfactants

Preferably, the cationic surfactants have the formula N+R1 R2R3R4 wherein R1 , R2, R3 and R4 are independently (C1 to C30) alkyl or benzyl. Preferably, one, two or three of R1 , R2, R3 and R4 are independently (C4 to C30) alkyl and the other R1 , R2, R3 and R4 group or groups are (C1 -C6) alkyl or benzyl. More preferably, one or two of R1 , R2, R3 and R4 are independently (C6 to C30) alkyl and the other R1 , R2, R3 and R4 groups are (C1 -C6) alkyl or benzyl groups. Optionally, the alkyl groups may comprise one or more ester (-OCO- or -COO-) and/or ether (-O-) linkages within the alkyl chain. Alkyl groups may optionally be substituted with one or more hydroxyl groups. Alkyl groups may be straight chain or branched and, for alkyl groups having 3 or more carbon atoms, cyclic. The alkyl groups may be saturated or may contain one or more carbon-carbon double bonds (e.g. oleyl). Alkyl groups are optionally ethoxylated on the alkyl chain with one or more ethyleneoxy groups. Suitable cationic surfactants for use in conditioner compositions according to the invention include cetyltrimethylammonium chloride, behenyltrimethylammonium chloride, cetylpyridinium chloride, tetramethylammonium chloride, tetraethylammonium chloride, octyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octyldimethylbenzylammonium chloride, decyldimethylbenzylammonium chloride, stearyldimethylbenzylammonium chloride, didodecyldimethylammonium chloride, dioctadecyldimethylammonium chloride, tallowtrimethylammonium chloride, dihydrogenated tallow dimethyl ammonium chloride (eg, Arquad 2HT/75 from Akzo Nobel), cocotrimethylammonium chloride, PEG-2-oleammonium chloride and the corresponding hydroxides thereof. Further suitable cationic surfactants include those materials having the CTFA designations Quaternium-5, Quaternium-31 and Quaternium-18. Mixtures of any of the foregoing materials may also be suitable. A particularly useful cationic surfactant for use in conditioners according to the invention is cetyltrimethylammonium chloride, available commercially, for example as GENAMIN CTAC, ex Hoechst Celanese. Another particularly useful cationic surfactant for use in conditioners according to the invention is behenyltrimethylammonium chloride, available commercially, for example as GENAMIN KDMP, ex Clariant. Another example of a class of suitable cationic surfactants for use in the invention, either alone or together with one or more other cationic surfactants, is a combination of (i) and (ii) below:

(i) an amidoamine corresponding to the general formula (I) R1 CONH(CH₂)mN(R2)R3

in which R1 is a hydrocarbyl chain having 1 0 or more carbon atoms, R2 and R3 are independently selected from hydrocarbyl chains of from 1 to 1 0 carbon atoms, and m is an integer from 1 to about 1 0; and

(ii) an acid.

As used herein, the term hydrocarbyl chain means an alkyl or alkenyl chain. Preferred amidoamine compounds are those corresponding to formula (I) in which R1 is a hydrocarbyl residue having from about 1 1 to about 24 carbon atoms, R2 and R3 are each independently hydrocarbyl residues, preferably alkyl groups, having from 1 to about 4 carbon atoms, and m is an integer from 1 to about 4. Preferably R2 and R3 are methyl or ethyl groups. Preferably m is 2 or 3, i.e. an ethylene or propylene group.

Preferred amidoamines useful herein include stearamido-propyldimethylamine, stearamidopropyldiethylamine, stearamidoethyldiethylamine, stearamidoethyldimethylamine, palmitamidopropyldimethylamine, palmitamidopropyl-diethylamine, palmitamidoethyldiethylamine, palmitamidoethyldimethylamine, behenamidopropyldimethyl-amine, behenamidopropyldiethylmine, behenamidoethyldiethyl-amine, behenamidoethyldimethylamine, arachidamidopropyl-dimethylamine, arachidamidopropyldiethylamine, arachid-amidoethyldiethylamine, arachidamidoethyldimethylamine, and mixtures thereof. Particularly preferred amidoamines useful herein are stearamidopropyldimethylamine, stearamidoethyldiethylamine, and mixtures thereof.

Commercially available amidoamines useful herein include: stearamidopropyldimethylamine with tradenames LEXAMINE S-13 available from Inolex (Philadelphia Pennsylvania, USA) and AMI DOAMINE MSP available from Nikko (Tokyo, Japan), stearamidoethyldiethylamine with a tradename AMI DOAMINE S available from Nikko, behenamidopropyldimethylamine with a tradename INCROMINE BB available from Croda (North Humberside, England), and various amidoamines with tradenames SCHERCODINE series available from Scher (Clifton New Jersey, USA).

The acid may be any organic or mineral acid which is capable of protonating the amidoamine in the conditioner composition. Suitable acids useful herein include hydrochloric acid, acetic acid, tartaric acid, fumaric acid, lactic acid, malic acid, succinic acid, and mixtures thereof. Preferably, the acid is selected from the group consisting of acetic acid, tartaric acid, hydrochloric acid, fumaric acid, lactic acid and mixtures thereof.

The primary role of the acid is to protonate the amidoamine in the hair treatment composition thus forming a tertiary amine salt (TAS) in-situ in the hair treatment composition. The TAS in effect is a non-permanent quaternary ammonium or pseudo-quaternary ammonium cationic surfactant. Suitably, the acid is included in a sufficient amount to protonate more than 95 mole % (20 °C) of the amidoamine present. In conditioners of the invention, the level of cationic surfactant will generally range from 0.01 to 10, more preferably 0.05 to 7.5, most preferably 0.1 to 5 % by weight of the composition.

Silicone Conditioning Agent

The compositions of the invention can contain emulsified droplets of a silicone conditioning agent, for enhancing conditioning performance as previously described.

Non-silicone Oils

Compositions according to the present invention may also comprise a dispersed, non-volatile, water-insoluble, non-silicone oily conditioning agent. Preferably such non-silicone oily conditioning agents are present in the hair conditioning compositions of the invention. By "insoluble" is meant that the material is not soluble in water (distilled or equivalent) at a concentration of 0.1 % w/w at 25 °C. Suitable non-silicone oils are selected from hydrocarbon oils, fatty esters and mixtures thereof.

Straight chain hydrocarbon oils will preferably contain from about 12 to about 30 carbon atoms. Also suitable are polymeric hydrocarbons of alkenyl monomers, such as C2-C6 alkenyl monomers. Specific examples of suitable hydrocarbon oils include paraffin oil, mineral oil, saturated and unsaturated dodecane, saturated and unsaturated tridecane, saturated and unsaturated tetradecane, saturated and unsaturated pentadecane, saturated and unsaturated hexadecane, and mixtures thereof. Branched-chain isomers of these compounds, as well as of higher chain length hydrocarbons, can also be used.

Suitable fatty esters are characterised by having at least 10 carbon atoms, and include esters with hydrocarbyl chains derived from fatty acids or alcohols, Monocarboxylic acid esters include esters of alcohols and/or acids of the formula R'COOR in which R' and R independently denote alkyl or alkenyl radicals and the sum of carbon atoms in R' and R is at least 10, preferably at least 20. Di- and trialkyl and alkenyl esters of carboxylic acids can also be used. Particularly preferred fatty esters are mono-, di- and triglycerides, more specifically the mono-, di-, and tri-esters of glycerol and long chain carboxylic acids such as C1 -C22 carboxylic acids. Preferred materials include cocoa butter, palm stearin, sunflower oil, soyabean oil and coconut oil.

The oily or fatty material is suitably present at a level of from 0.05 to 10, preferably from 0.2 to 5, more preferably from about 0.5 to 3 % w/w of the composition of the invention.

Fatty Alcohols

Hair conditioning compositions of the invention will typically also incorporate a fatty alcohol. The combined use of fatty alcohols and cationic surfactants in conditioning compositions is believed to be especially advantageous, because this leads to the formation of a lamellar phase, in which the cationic surfactant is dispersed. Representative fatty alcohols comprise from 8 to 22 carbon atoms, more preferably 16 to 22. Fatty alcohols are typically compounds containing straight chain alkyl groups. Examples of suitable fatty alcohols include cetyl alcohol, stearyl alcohol and mixtures thereof. The use of these materials is also advantageous in that they contribute to the overall conditioning properties of compositions of the invention.

The level of fatty alcohol in conditioners of the invention will generally range from 0.01 to 10, preferably from 0.1 to 8, more preferably from 0.2 to 7, most preferably from 0.3 to 6 % w/w by weight of the composition. The weight ratio of cationic surfactant to fatty alcohol is suitably from 1 :1 to 1 :10, preferably from 1 :1 .5 to 1 :8, optimally from 1 :2 to 1 :5. If the weight ratio of cationic surfactant to fatty alcohol is too high, this can lead to eye irritancy from the composition. If it is too low, it can make the hair feel squeaky for some consumers. Examples

Example 1 : Effect of pre-treating hair with catechin/horseradish peroxidase Materials

Human natural white hair fibres, International Hair Importers, USA

Platine precision lightening powder, (50 % persulphates, 24.1 % silicates and 2.6 % ammonium chloride), L'Oreal, France

Excel cream peroxide 9 % 30 vol, Excel (GS) Ltd., UK

Britton-Robinson (BR) buffer

Hydrogen peroxide 3%, Sigma, UK

(+)-catechin, Sigma, UK

Dimethyl sulphoxide (DMSO), Sigma, UK

Horseradish peroxidase, 53 U/mg (1 Unit = 1 mg purpurogallin in 20 s at 20°C and pH 6) (HRP I, Sigma, UK)

Methods

Preparation of 0.5M Britton-Robinson buffer

41 .015 g sodium acetate (Sigma, UK)

30.915 g boric acid (Sigma, UK) 68.045 g potassium monobasic phosphate (Sigma, UK) or 87.1 g potassium dibasic phosphate (Sigma, UK)

1 . Combine 41 .015g of sodium acetate, 30.915g of boric acid and 68.045g of potassium monobasic phosphate or 87.1 g potassium dibasic phosphate.

2. Dissolve in water and make up to 1 litre.

3. Store at room temperature. When using, aliquot out the required amount and pH to required pH using phosphoric acid or potassium hydroxide. General

Two sets of hair fibres were prepared (3 hairs per set). The hairs in Set A were analysed by confocal Raman spectroscopy first untreated, then after colouring with catechin/enzyme, then after bleaching twice. The hairs in Set B were analysed by confocal Raman spectroscopy first untreated, then after bleaching twice.

Hair treatment and bleaching

Hairs were treated by combining 700 μΙ_ Britton-Robinson buffer (62.5 mM pH 6; final concentration 50 mM), 100 μΙ_ 3 % hydrogen peroxide and 100 μΙ_ (+)-catechin (100 mg/mL stock in DMSO) in a plastic trough. A hair fibre was placed into the trough, wet thoroughly and incubated at 32 *C for 5 minutes.

100 μΙ_ horseradish peroxidase (1 mg/mL in Britton-Robinson buffer, 62.5mM pH 6) was then added and rubbed into the hair. The hair and solution were then incubated at 32 'C for a further 5 minutes.

After 5 minutes incubation the hair was washed by swirling in a beaker of MilliQ water for approximately 30 seconds. The hair fibre was then allowed to air dry.

The above method was repeated twice (3 treatments in total).

Hair fibres were bleached twice using L'Oreal Platine Precision lightening powder and Excel cream peroxide according to the manufacturers' instructions (30 minutes each treatment). After the second bleach treatment, the hair fibre was shampoo washed twice (washed with shampoo for 30 seconds and then rinsed with tap water for 30-60 seconds), then air dried.

Confocal Raman spectroscopy

Confocal Raman spectroscopy was used to assess the structure of each hair fibre. Raman spectra were collected using a WITec Alpha 300 R system. A 785 nm laser was used as the excitation source at an operating power of 50 mW before the objective. This was selected to avoid sample damage while still resulting in sufficient sample excitation. A Zeiss 100x/0.9 air objective and a collection time of 60 seconds for each point was used. Hair strands were fixed to a glass microscope slide using tape, ensuring that the hair fibre was pulled straight without stretching. These were mounted onto an x-y piezo stage, with 3 nm positioning accuracy, controlled via WITec software. Spectra from two locations on each hair were recorded. At each sampling position, spectra were collected at multiple points in the xz plane to create a data map representing a transverse section of the hair. Along the length of the hair (x direction) spectra were collected over 60 μιτι at 2 μιη intervals. Points with the same x coordinates were then collected at depth intervals of 2 μιη intervals (z direction) up to 16 μιτι deep. These dimensions allowed both the cuticle and the cortex to be studied. Spectra from the same areas of each fibre before and after each treatment were collected.

The collected data maps were removed of cosmic rays using WITec software. Data was then processed in MATLAB (Mathworks, Natick, Mass., USA) where further cosmic rays were removed and the data was baseline corrected.

Results

Little change in the cuticle of hair fibres was seen after catechin/horseradish peroxidase/hydrogen peroxide treatment. Key changes in the cortex of hair fibres after treatment were observed as an increase of the band at 674.5 cm^"1 (C-S band) and at 704.4 cm^"1. The S-S band at approximately 510 cm^"1 was also seen to increase when individual data sets were examined. Thus catechin/horseradish peroxidase/hydrogen peroxide treatment appears to have a greater effect on the cortex than the cuticle of hair fibres.

The major effect of bleaching on the cuticle was sulphur oxidation shown by an increase in the S-0 band at 1042 cm^"1, indicating an increase in cysteic acid. A further effect is a decrease of the S-S band at approximately 510 cm^"1 (decrease in S-S cross linkages). This agrees with work by Kuzuhara (Biopolymers, 81 , 506-514 (2006))who reported that bleaching of hair results in increased sulphur oxidation and a decrease of disulphide bonds in the hair fibre. Bleaching hair after pre-treatment with catechin/horseradish peroxidase/hydrogen peroxide results in the same oxidation effects, but to a different extent.

The major effect of bleaching on the cortex was an increase of the S-O band at 1042 cm^"1. In the hair fibres treated with catechin/horseradish peroxidase/hydrogen peroxide, there is a less intense oxidation effect than that seen in fibres without catechin/horseradish peroxidase/hydrogen peroxide pre- treatment (c.f. S-O intensity with respect to the phenylalanine band (1004 cm^"1)). The observed decrease in S-S band at 507 cm^"1 suggested a decrease in S-S cross linkages. A decrease of S-S cross linkages and increase in S-O content is consistent with cystine oxidation.

The ratio of the S-O band (1020-1070 cm^"1) to the phenylalanine band (990-1016 cm^"1) was calculated from a sample taken at five points along each hair. The points from each hair were then averaged to give a representative ratio for the hairs at each treatment stage. Figure 1 shows that upon bleaching the S-O band/ phenylalanine band ratio is increased. Hairs pre-treated with catechin/horseradish peroxidase/hydrogen peroxide show a smaller increase in ratio than those bleached without catechin/horseradish peroxidase/hydrogen peroxide pre- treatment. At the cuticle (0 μιτι) larger difference between untreated and bleached samples are observed, suggesting that the cuticle is more affected by bleaching than the cortex.

Figure 2 illustrates a decrease in the S-S band/phenylalanine band ratio on bleaching suggesting S-S cross linkages have been broken. Conclusion

Upon bleaching the hairs undergo sulphur oxidation and the amount of S-S cross linkages decreases. This is consistent with the oxidation of cystine to produce cysteic acid. Pre-treatment of hairs with catechin/horseradish peroxidase/hydrogen peroxide before bleaching reduces the amount of sulphur oxidation. A small protective effect in the cuticle is seen and a larger protective effect in the cortex is seen. This indicates that pre-treating hairs with catechin/horseradish peroxidase/hydrogen peroxide protects hair fibres from oxidative damage.

Example 2

Materials

Human dark brown hair switches (International Hair Importers, USA)

Horseradish peroxidase, 274 U/mg (1 Unit = 1 mg purpurogallin in 20 s at 20°C and pH 6) (HRP VI, Sigma, UK)

Soy bean peroxidase, 1840 U/mg (1 Unit = 1 μΜ change per minute at 30 °C and pH 6 guaiacol (Bio-Research Products, USA)

Laccase 51003 (Myceliophthora thermophila), 1000 U (LAMU)/g (ml) (1 LAMU = 1 μΜ change per minute at 30 °C and pH 7.5 syringaldazine (Novozymes, Denmark)

Methods

Hair bleaching

Selected 2" hair switches were bleached once using L'Oreal Platine Precision lightening powder and Excel cream peroxide according to the manufacturers' instructions (30 minutes each treatment).

Hair treatment

4200 μΙ_ Britton-Robinson buffer (62.5 mM pH 5; final concentration 50 mM)

600 μΙ hydrogen peroxide 3% (SBP- or HRP-treated sample and (+)-catechin /H₂0₂ treated sample) or 600 μΙ_ milliQ water (laccase-treated sample and (+)-catechin treated sample)

600 μΙ_ (+)-catechin, 100mg/ml_ stock in DMSO The reagents listed above were combined in 15 ml Falcon centrifuge tubes. Unbleached and bleached hair switches were placed into the tubes and squashed down, wetting the hair thoroughly (one switch per tube). The switch/reagents were then incubated at 32 °C for 15 minutes. 30 Units horseradish peroxidase (HRP), soy bean peroxidase (SBP) or laccase (in Britton-Robinson buffer pH 5, total volume 600 μΙ) were then added as appropriate to the tubes. 600 μΙ Britton-Robinson buffer pH 5 were added to the tubes containing the (+)-catechin and (+)-catechin/H₂0₂ treated switches. The hair switches were then incubated at 32 °C for another 15 minutes. After incubation the switches were washed by swirling in a beaker of milliQ water for approximately 1 minute. The hair was then shampoo washed by rubbing with shampoo for 30 seconds and subsequently rinsing under tap water for 60 seconds. The hair was then dried with a hairdryer and combed. The above method was repeated 4 times (5 treatments in total). Untreated switches were washed 5 times with shampoo, rinsed and air dried.

DSC

DSC measures the denaturation temperature of the · -helical proteins in the microfibrils of the hair fibre. This temperature is influenced by the cross-link density of the surrounding matrix proteins (Wortmann et al., J. Cosmet. Sci., 53, 219-228 (2002)). A higher denaturation peak temperature indicates greater integrity of the fibre.

Damage repair was assessed using DSC. A Mettler Toledo DSC1 analyser was used. The hair was shaved, using clippers, into 1 -2 mm lengths. Approximately 5 mg of sample was weighed into a pressure resistant (20 bar), stainless steel, large volume pan (120 · L capacity). 50 · L of water was added and the pan was sealed. The samples were then mixed using a rotary mixer and left overnight to allow the water to equilibrate throughout the sample. Samples were run through a temperature programme of 100 - 180 ^QC at a rate of 5 -CI min. The helix transition temperature was measured. Each sample was measured three times.

Results

The results are summarised in Table 2 Table 2: Denaturation peak temperature (°C) for (+)-catechin, horseradish peroxidase, and hydrogen peroxide combination; (+)-catechin, soy bean peroxidase, and hydrogen peroxide combination; (+)-catechin and laccase combination; on dark brown hair unbleached, and bleached x1 . Standard errors at 95 % confidence limits are provided.

Unbleached (°C) Bleached x1 (°C)

No treatment 147.38 +/- 0.72 143.60 +/- 0.65

(+)-Catechin / H202 /HRP 151 .96 +/- 0.09 154.76 +/- 0.41

(+)-Catechin / H202 / SBP n/a 154.19 +/- 0.06

(+)-Catechin / laccase 150.80 +/- 0.18 153.85 +/- 0.16

Conclusion

Analysis by DSC shows that treatment with any of the foregoing compositions on unbleached or bleached dark brown hair increases the denaturation temperature.

Example 3

Materials (additional)

Myricetin (Sigma, UK)

Gossypetin (Extrasynthese, France)

Luteolin (Sigma, UK)

Apigenin (Sigma, UK)

Naringenin (Sigma, UK)

Methods

Hair bleaching

Selected 2" hair switches were bleached twice using L'Oreal Platine Precision lightening powder and Excel cream peroxide according to the manufacturers' instructions (30 minutes each treatment).

Hair treatment

4200 · L Britton-Robinson buffer (62.5 mM pH 5; final concentration 50 mM) 600 · Ι hydrogen peroxide 3% (HRP-treated samples) or 600 · Ι_ milliQ water (laccase-treated samples)

600 · L flavanoid ((+)-catechin, myricetin, gossypetin, luteolin, apigenin or naringenin), 10mg/ml_ stock in DMSO

The reagents listed above were combined in 15 ml_ Falcon centrifuge tubes. Bleached hair switches were placed into the tubes and squashed down, wetting the hair thoroughly (one switch per tube). The switch/reagents were then incubated at 32 °C for 15 minutes. 30 Units horseradish peroxidase (HRP) or laccase (in Britton- Robinson buffer pH 5, total volume 600 μΙ_) were then added as appropriate to the tubes. The hair switches were then incubated at 32 °C for another 15 minutes. After incubation the switches were washed by rinsing under running tap water for 1 minute. The hair was then shampoo washed by rubbing with shampoo for 30 seconds and subsequently rinsing under tap water for 60 seconds. The hair was then dried with a hairdryer and combed. The above method was repeated twice (3 treatments in total). Untreated switches were washed 3 times with shampoo, rinsed and dried as described above.

DSC

Denaturation temperature was assessed by DSC using the method described in example 2. Untreated samples were measured three times. All other samples were measured six times.

Results

The results are summarised in Tables 3a, 3b and 3c

Table 3a: Denaturation peak temperature (°C) for (+)-catechin and laccase combination; myricetin, hydrogen peroxide and horseradish peroxidase combination; and gossypetin, hydrogen peroxide and horseradish peroxidase combination on double bleached natural white hair. Standard errors at 95 % confidence limits are provided.

Bleached x2 (°C)

No treatment 136.97 +/- 0.04

(+)-Catechin / laccase 148.85 +/- 0.43 Myricetin / H₂0₂ / HRP 149.75 +/- 0.64

Gossypetin / H₂0₂ / HRP 149.61 +/- 0.29

Table 3b: Denaturation peak temperature (°C) for (+)-catechin and laccase combination; luteolin, hydrogen peroxide and horseradish peroxidase combination; and apigenin, hydrogen peroxide and horseradish peroxidase combination on double bleached natural white hair. Standard errors at 95 % confidence limits are provided.

Table 3c: Denaturation peak temperature (°C) for (+)-catechin and laccase combination; and naringenin, hydrogen peroxide and horseradish peroxidase combination; on double bleached natural white hair. Standard errors at 95 % confidence limits are provided.

Conclusion

Analysis by DSC shows that treatment with any of the foregoing compositions on bleached natural white hair increases the denaturation temperature.

In Example 1 we demonstrate that pre-treatment of hairs with (+)-catechin /horseradish peroxidase/hydrogen peroxide before bleaching reduces the amount of sulphur oxidation. This indicates that pre-treating hairs with (+)-catechin /horseradish peroxidase/hydrogen peroxide protects hair fibres from oxidative damage. In Example 2 we demonstrate that treatment of unbleached or bleach- damaged hair with (+)-catechin/horseradish peroxidase/hydrogen peroxide, (+)- catechin/soybean peroxidase/hydrogen peroxide and (+)-catechin/laccase increases the denaturation temperature of the hair fibres (as measured by DSC). A higher denaturation peak temperature indicates greater integrity of the fibre. In Example 3 we demonstrate that treatment of bleach-damaged hair with (+)catechin /laccase, myricetin/horseradish peroxidase/ hydrogen peroxide, gossypetin/ /horseradish peroxidase/ hydrogen peroxide, luteolin/ /horseradish peroxidase/ hydrogen peroxide, apigenin/ /horseradish peroxidase/ hydrogen peroxide and naringenin/ horseradish peroxidase/ hydrogen peroxide increases hair fibre denaturation temperature (as measured by DSC). A higher denaturation peak temperature indicates greater integrity of the fibre. Pre- treatment of hair fibres with myricetin/ /horseradish peroxidase/ hydrogen peroxide, gossypetin /horseradish peroxidase/ hydrogen peroxide, luteolin/ /horseradish peroxidase/ hydrogen peroxide, apigenin/ horseradish peroxidase/ hydrogen peroxide or naringenin/ horseradish peroxidase/ hydrogen peroxide before bleaching is therefore also expected to protect hair fibres from oxidative damage.

Claims

A method of preventing hair fibre damage, the method comprising the step of applying a hair composition to unbleached hair fibres, the hair composition comprising:

(a) A flavonoid or a derivative thereof; and either

(c) A laccase;

preferably wherein the hair fibre damage is caused by bleaching.

A method according to claim 1 , wherein the flavonoid is selected from the group consisting of flavones, isoflavones, flavans, isoflavans, flavanones, flavonols, flavan-3-ols, dihydroflavonol, flavanonols, anthocyanidins, proanthocyanidins, auron, chalcone, dihydrochalcone, flavonolignans, and derivatives thereof.

A method according to claim 2,

wherein the flavone is selected from the group consisting of apigenin, luteolin and chrysin;

wherein the isoflavone is selected from the group consisting of daidzein, genistein and formononetin;

wherein the flavan is 4'-hydroxy-5,6-dimethoxyflavan;

wherein the isoflavan is glabridin or licoricidin;

wherein the flavanone is naringenin or eriodictyol;

wherein the flavonol is selected from the group consisting of myricetin, kaempferol, gossypetin and quercetin;

wherein the flavan-3-ol is selected from the group consisting of catechin, theaflavin, gallocatechin, catechin gallate, gallocatechin gallate, epicatechin, epigallocatechin, epigallocatechin gallate and epigallocatechin gallate;

wherein the dihydroflavonol is taxifolin or aromadendrin; wherein the anthocyanidin is selected from the group consisting of cyanidin, delphinidin, pelargonidin and malvidin;

wherein the aurone is sulphuretin;

wherein the chalcone is 2'-hydroxy-4-methoxy-chalcone;

wherein the dihydrochalcone is phloretin or phloridzin and

wherein the flavonolignan is silibinin or silichristin.

4. A method according to claim 1 , wherein the flavonoid is selected from the group consisting of silibinin, silandrin, 3,4-dihydroxyflavone, hesperidin (glycoside), naringin (naringenin glycoside), amentoflavone, rutin, eriodictyol-

7-O-glucoside, quercitrin, kaempferol, pinostrobin and biochanin A.

5. A method according to claim 1 , wherein the flavonoid is selected from the group consisting of flavones, flavanones, flavonols and flavan-3-ols.

6. A method according to claim 1 , wherein the flavonoid is selected from the group consisting of (+)-catechin, myricetin, gossypetin, luteolin, apigenin and naringenin.

7. A method according to any one of the preceding claims, wherein the hair composition comprises 0.01 - 10, preferably 0.1 - 5 % w/w flavonoid.

8. A method according to any one of the preceding claims, wherein the hair composition comprises 0.0001 - 5, preferably 0.001 - 1 % w/w peroxidase or laccase.

9. A method according to any one of the preceding claims, wherein the peroxidase is a non-animal haem peroxidase from class II (fungi) or class III (plants and algae).

10. A method according to claim 9, wherein the peroxidase is obtained from the group consisting of Arabidopsis thaliana, horse radish, barley, peanut soybean, tobacco, and turnip (plants), Chlorophyta spirogyra (green algae), Arthromyces ramosus and Corprinus cinereus (fungi).

1 1. A method according to any one of the preceding claims, wherein the hair composition comprises 0.0001 - 3 preferably 0.001 - 1 , most preferably 0.01 - 1 % w/w hydrogen peroxide.

12. A method according to any one of claims 1 to 10, wherein the hydrogen peroxide generator comprises a hydrogen peroxide generating oxidase, a substrate and oxygen.

13. A method according any one of claims 1 to 8, wherein the laccase is selected from a fungal or a plant source such as those from the group consisting of the Aspergillus, Botrytis, Ceriporiopsis, Cerrena, Chaetomium, Coprinus, Coriolus, Neurospora, Panus, Phanerochaete, Pleurotus, Polyporus, Pycnoporus and Trametes genera, and Rhus vernicifera.

14. A method according to any one of the preceding claims wherein the hair composition is a shampoo composition or hair conditioning composition.