Hair treatment compositions

Abstract

A hair cleansing composition, comprising: i) 0.2 to 2.5 wt %, preferably from 0.5 to 2 wt %, of a glutamate salt, preferably sodium glutamate, most preferably monosodium glutamate; and ii) a cleansing surfactant; wherein the pH is in the range of from 4.1 to 6, preferably 4.1 to less than 5; and wherein the composition is free from parabens.

Description

[0001] P0001170WQ

[0002] - 1 -

[0003] HAIR TREATMENT COMPOSITIONS

[0004] FIELD OF THE INVENTION

[0005] The invention relates to the hair cleansing compositions for the repair of hair damage and

[0006] 5 methods of use thereof.

[0007] BACKGROUND AND PRIOR ART

[0008] Consumers regularly subject their hair to intensive treatment, and care and styling routines to help them achieve their desired look. The actions performed by consumers

[0009] 10 introduce modifications to the chemistry of hair keratin protein which results in micro- and macro-structural changes and, in turn, changes fibre physical properties: the consequences of these are generally perceived by the consumer as damage.

[0010] Combing and brushing of hair mechanically abrades the fibre cuticle making this rougher

[0011] 15 and increasing the frictional characteristics. Hair lightening, such as bleaching, or colouring treatments generally involve an oxidative step to break down melanin and develop the new hair colour, but these processes also oxidise the hair fibre protein and the endogenous lipids. These reactions alter the number and types of covalent and non- covalent bonds within the fibre, and impact the thermal stability and mechanical

[0012] 20 properties of the hair. The internal protein of damaged hair typically has a reduced denaturation temperature compared to that of virgin hair.

[0013] Various organic molecules and combinations thereof have been suggested for use in the treatment of damaged hair.

[0014] 25

[0015] WO 2004054526 describes hair treatment compositions for the care and repair of damaged hair, and for improving hair manageability, comprising a disaccharide, in particular trehalose.

[0016] 30 US4975274 (Chesbrough-Pond’s) discloses the use of glutamic acid and water soluble salts thereof as an additive for water-containing hair care products so that the hair when treated with such products will have a desirable flexibility and resistance to breakage. A specific hair care composition consists of: Water (53.70 %), Sodium Lauryl 2 EO Sulfate P0001170WQ

[0017] - 2 -

[0018] (38 %), Cocodiethanolamide (3 %) Cocoamidopropyl betaine (1.75 %), Disodium EDTA (0.05 %), Methylparaben (0.15 %), Propylparaben (0.10 %), Citric Acid (0.25 %), Colorant (0.065 %), DMDM Hydantoin (0.30 %), Perfume (0.50 %), Monosodium Glutamate (2.00 %) and Sodium chloride (0.17 %).

[0019] 5

[0020] We have now surprisingly found that the inclusion of a glutamate salt, preferably sodium glutamate, in a shampoo at a pH of greater than 4.1, provides damage repair to hair, particularly repair of the internal protein.

[0021] 10 DEFINITION OF THE INVENTION

[0022] In a first aspect of the invention, there is provided a hair cleansing composition comprising: i) 2 to 2.5 wt %, preferably from 0.5 to 2 wt %, of a glutamate salt, preferably sodium

[0023] 15 glutamate, most preferably monosodium glutamate; and ii) a cleansing surfactant; wherein the pH is in the range of from 4.1 to 6, preferably 4.1 to 5, most preferably 4.1 to

[0024] 20 less than 5; and wherein the composition is free from parabens.

[0025] A second aspect of the invention provides a method of repairing damaged internal protein of hair, comprising the step of applying a composition as defined for use in the first aspect

[0026] 25 of the invention. The method results in an increase in the denaturation temperature of the internal proteins of the hair. The increase in denaturation temperature is compared with the same composition that does not comprise a glutamate salt.

[0027] The method preferably additionally comprises the step of leaving the composition on the

[0028] 30 hair for 2 seconds to 20 minutes, preferably 10 seconds to 3 minutes, most preferably 20 seconds to 1 minute, and then rinsing the composition from the hair.

[0029] In an alternative embodiment, the composition may be left in the hair until the next washing event. This is particularly suitable where the composition is a leave-on conditioner. P0001170WQ

[0030] - 3 -

[0031] Preferably, the method additionally comprises the step of repeating the application of the composition to the hair. Preferably, the step of repeating the application of the composition to the hair is made during a later treatment and is repeated 1 to 10 times. This provides progressive increase in the denaturation temperature of the internal

[0032] 5 proteins of the hair.

[0033] The composition is preferably applied to the hair multiple times, to give progressive damage repair, that increases when hair, that has been previously treated with the composition, is treated with the composition again . This is preferably an increase in the

[0034] 10 denaturation temperature of the protein. In this way, it is possible to increase the denaturation temperature of the protein of damaged hair, preferably bleached hair, to that of virgin hair, preferably higher than that of virgin hair.

[0035] Hair damage can be measured in different ways. This invention focusses on the

[0036] 15 structural integrity of hair cortex proteins, as can be determined by Differential Scanning Calorimetry, single-fibre mechanical testing and numerous other methods. The damage repair is preferably an increase in the denaturation temperature of the internal protein of hair.

[0037] 20 The Hair

[0038] The hair can be virgin hair or damaged hair.

[0039] It is reported in “Thermal Analysis of Human Hair and Keratin” by J. Feughelman, published in the Journal of Applied Polymer Science, that the denaturation temperature of

[0040] 25 virgin hair, as measured by DSC, is from 150 to 160.

[0041] In the context of this invention, by virgin hair is meant hair that has not been subjected to intensive physical and / or chemical treatment, for example, bleaching, dyeing, perming, intensive heat treatment and strong and / or prolonged exposure to solar radiation. Hair

[0042] 30 that has been subjected to such intensive physical and / or chemical treatment has a lower denaturation temperature of the protein compared with the same hair before being subjected to intensive physical and / or chemical treatment. We have found a typical reduction in denaturation temperature of our virgin switches following intensive physical and / or chemical treatment of about 1.5 to 3.5 %. P0001170WC

[0043] - 4 -

[0044] Virgin hair includes hair that has sustained low levels of damage during the natural hair life cycle. By low levels of damage is meant damage where the denaturation temperature of the protein is not significantly reduced, for example estimated to be by between 0.5 to 2 %, preferably 0.5 to 1.5 % reduced compared to theoretically completely undamaged

[0045] 5 hair.

[0046] Sources of low level damage likely include but are not necessarily limited to washing, brushing, combing and limited solar photo-degradation for example.

[0047] 10 The hair is preferably damaged hair, where the denaturation temperature of the internal protein of the hair is reduced compared to hair that has not been damaged, for example subjected to intensive physical and / or chemical treatment.

[0048] The damage may be caused by mechanical means, for example combing and brushing,

[0049] 15 chemical means, exposure to heat, environmental means such as sunlight and exposure to damaging energy sources, for example light such as UV light. Chemical means includes treatments that involve an oxidative step, for example, hair lightening, such as bleaching, and colouring treatments, preferably chemical means, exposure to heat, environmental means such as sunlight and exposure to damaging energy sources, for

[0050] 20 example light such as UV light. Chemical means includes treatments that involve an oxidative step, for example, hair lightening, such as bleaching, and colouring treatments. The hair is preferably subjected to damage multiple times.

[0051] Preferably the hair is damaged by oxidative colouring, bleaching or exposure to UV light.

[0052] 25 Most preferably the hair is bleached more preferably bleached multiple times.

[0053] GENERAL DESCRIPTION OF THE INVENTION

[0054] Many raw materials contain, what are known in the industry as, carry-over ingredients. These are often used for example as processing aids, preservatives, emulsifiers, etc.

[0055] 30 These carry-over ingredients are present in very small quantities (for example less than 0.05 wt % of the total composition) and perform a function for the raw material (for example as an emulsifier for a silicone). Carry-over ingredients are present in the full compositions at levels that are too low to have a material effect on the properties of the composition. They are not intended to be part of the invention. P0001170WQ

[0056] - 5 -

[0057] The Glutamate Salt

[0058] The composition for use in the present invention comprises a glutamate salt.

[0059] Preferred examples include sodium glutamate, potassium glutamate, magnesium

[0060] 5 diglutamate, calcium diglutamate, ammonium glutamate and mixtures thereof.

[0061] More preferably the glutamate salt is sodium glutamate, most preferably monosodium glutamate.

[0062] 10 The amount of glutamate salt is from 0.01 to 3 wt %, preferably 0.2 to 2.5 wt %, most preferably from 0.5 to 2 wt %, by weight of the total composition.

[0063] The pH of the composition is in the range of from 4.1 to 6, preferably 4.1 to 5, more preferably 4.1 to less than 5, for example 4.1 to 4.9 or 4.2 to 4.8, most preferably 4.25 to

[0064] 15 less than 5.

[0065] Compositions for use in the method of the invention are preferably formulated as shampoos for the treatment of hair and subsequent rinsing.

[0066] 20 The hair treatment composition comprises a cleansing surfactant. The surfactant is preferably selected from an anionic surfactant, a nonionic surfactant, a zwitterionic or amphoteric surfactant and mixtures thereof, preferably anionic surfactant and a zwitterionic or amphoteric surfactant. Suitable and preferred surfactants are described below.

[0067] 25

[0068] 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.

[0069] 30 Suitably, the shampoo composition will comprise from 50 to 98%, preferably from 60 to 90% water by weight based on the total weight of the composition. P0001170WQ

[0070] - 6 -

[0071] Shampoo compositions according to the invention will generally comprise one or more anionic cleansing surfactants which are cosmetically acceptable and suitable for topical application to the hair.

[0072] 5 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

[0073] 10 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.

[0074] 15 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 dodecyl benzene sulphonate, sodium cocoyl isethionate, sodium lauryl

[0075] 20 isethionate, lauryl ether carboxylic acid and sodium N-lauryl sarcosinate.

[0076] Preferred anionic cleansing surfactants are sodium lauryl sulphate, sodium lauryl ether sulphate (n)EO, (where n is from 1 to 3), sodium lauryl ether sulphosuccinate(n)EO, (where n is from 1 to 3), ammonium lauryl sulphate, ammonium lauryl ether sulphate(n)EO, (where

[0077] 25 n is from 1 to 3), sodium cocoyl isethionate and lauryl ether carboxylic acid (n) EO (where n is from 10 to 20).

[0078] Mixtures of any of the foregoing anionic cleansing surfactants may also be suitable.

[0079] 30 The total amount of anionic cleansing surfactant in shampoo compositions of the invention generally ranges from 0.5 to 45%, preferably from 1.5 to 35%, more preferably from 5 to 20% by total weight anionic cleansing surfactant based on the total weight of the composition. P0001170WG

[0080] - 7 -

[0081] Optionally, a shampoo composition of the invention may contain further ingredients as described below to enhance performance and / or consumer acceptability.

[0082] The composition can include co-surfactants, to help impart aesthetic, physical or cleansing

[0083] 5 properties to the composition.

[0084] An example of a co-surfactant is a nonionic surfactant, which can be included in an amount ranging from 0.5 to 8%, preferably from 2 to 5% by weight based on the total weight of the composition.

[0085] 10

[0086] For example, representative nonionic surfactants that can be included in shampoo compositions of the invention include condensation products of aliphatic (Cs - 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.

[0087] 15

[0088] Other representative 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, the APG is one which comprises

[0089] 20 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:

[0090] RO - (G)n

[0091] 25 wherein R is a branched or straight chain alkyl group which may be saturated or unsaturated and G is a saccharide group.

[0092] R may 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

[0093] 30 value of R lies between about 9.5 and about 10.5. G may be selected from C5 or Cs 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. P0001170WQ

[0094] - 8 -

[0095] The degree of polymerisation, n, may have a value of from about 1 to about 10 or more. Preferably, the value of n lies from about 1.1 to about 2. Most preferably the value of n lies from about 1.3 to about 1.5.

[0096] 5 Suitable alkyl polyglycosides for use in the invention are commercially available and include for example those materials identified as: Oramix NS10 ex Seppic; Plantaren 1200 and Plantaren 2000 ex Henkel.

[0097] Other sugar-derived nonionic surfactants which can be included in compositions of the

[0098] 10 invention include the C10-C18 N-alkyl (Ci-Ce) polyhydroxy fatty acid amides, such as the C12- C18 N-methyl glucamides, as described for example in WO 92 06154 and US 5 194639, and the N-alkoxy polyhydroxy fatty acid amides, such as C10-C18 N-(3-methoxypropyl) glucamide.

[0099] A preferred example of a co-surfactant is an amphoteric or zwitterionic surfactant, which can

[0100] 15 be included in an amount ranging from 0.5 to about 8%, preferably from 1 to 4% by weight based on the total weight of the composition.

[0101] Examples of amphoteric or zwitterionic surfactants include alkyl amine oxides, alkyl betaines, alkyl amidopropyl betaines, alkyl sulphobetaines (sultaines), alkyl glycinates, alkyl

[0102] 20 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, cocam idopropyl betaine and sodium

[0103] 25 cocoamphoacetate.

[0104] A particularly preferred amphoteric or zwitterionic surfactant is cocam idopropyl betaine.

[0105] Mixtures of any of the foregoing amphoteric or zwitterionic surfactants may also be

[0106] 30 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. P0001170WQ

[0107] - 9 -

[0108] The total amount of surfactant (including any co-surfactant, and / or any emulsifier) in a shampoo composition of the invention is generally from 1 to 50%, preferably from 2 to 40%, more preferably from 10 to 25% by total weight surfactant based on the total weight of the composition.

[0109] 5

[0110] Cationic polymers are preferred ingredients in a shampoo composition of the invention for enhancing conditioning performance.

[0111] Suitable cationic polymers may be homopolymers which are cationically substituted or may

[0112] 10 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

[0113] 15 extensional viscosity leading to stringiness of the composition when it is poured.

[0114] 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

[0115] 20 described in the CTFA Cosmetic Ingredient Directory, 3rd edition. 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.

[0116] 25

[0117] 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

[0118] 30 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. P0001170WC

[0119] - 10 -

[0120] 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.

[0121] 5 Amine substituted vinyl monomers and amines can be polymerised in the amine form and then converted to ammonium by quaternization.

[0122] The cationic polymers can comprise mixtures of monomer units derived from amine- and / or quaternary ammonium-substituted monomer and / or compatible spacer monomers.

[0123] 10

[0124] Suitable cationic polymers include, for example: cationic diallyl quaternary ammonium-containing polymers including, for example, dimethyldiallylammonium chloride homopolymer and copolymers of

[0125] 15 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 U.S. Patent

[0126] 20 4,009,256); cationic polyacrylamides(as described in WO95 / 22311).

[0127] Other cationic polymers that can be used include cationic polysaccharide polymers, such as

[0128] 25 cationic cellulose derivatives, cationic starch derivatives, and cationic guar gum derivatives.

[0129] Cationic polysaccharide polymers suitable for use in compositions of the invention include monomers of the formula:

[0130] A-O-[R-N+(R1)(R2)(R3)X-],

[0131] 30 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, R2and R3independently represent alkyl, aryl, alkylaryl, arylalkyl, alkoxyalkyl, or alkoxyaryl groups, each group containing up P0001170WG

[0132] - 11 - to about 18 carbon atoms. The total number of carbon atoms for each cationic moiety (i.e. , the sum of carbon atoms in R1, R2and R3) is preferably about 20 or less, and X is an anionic counterion.

[0133] 5 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 U.S. Patent 3,962,418), and copolymers of etherified cellulose and starch (e.g. as described in U.S. Patent 3,958,581).

[0134] 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 and JAGUAR C17.

[0135] Mixtures of any of the above cationic polymers may be used.

[0136] 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% by total weight of cationic polymer based on the total weight of the composition.

[0137] Preferably an aqueous shampoo composition of the invention further comprises a suspending agent. Suitable suspending agents are selected from polyacrylic acids, crosslinked 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

[0138] 30 493. Polymers of acrylic acid cross-linked with a polyfunctional agent may also be used; P0001170WC

[0139] - 12 - 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. All Carbopol (trademark) materials are available from Goodrich.

[0140] 5

[0141] 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.

[0142] 10 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.

[0143] 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% by total

[0144] 15 weight of suspending agent based on the total weight of the composition.

[0145] Other ingredients

[0146] Hair cleansing compositions according to the invention, particularly water-based shampoos will preferably also contain one or more silicone conditioning agents.

[0147] 20

[0148] Particularly preferred silicone conditioning agents are silicone emulsions such as those formed from silicones such as polydiorganosiloxanes, in particular polydimethylsiloxanes which have the CTFA designation dimethicone, polydimethyl siloxanes having hydroxyl end groups which have the CTFA designation dimethiconol, and amino-functional

[0149] 25 polydimethyl siloxanes which have the CTFA designation amodimethicone.

[0150] The emulsion droplets may typically have a Sauter mean droplet diameter (D3,2) in the composition of the invention ranging from 0.01 to 20 micrometer, more preferably from 0.2 to 10 micrometer.

[0151] 30

[0152] A suitable method for measuring the Sauter mean droplet diameter (D3,2) is by laser light scattering using an instrument such as a Malvern Mastersizer. P0001170WG

[0153] - 13 -

[0154] Suitable silicone emulsions for use in compositions of the invention are available from suppliers of silicones such as Dow Corning and GE Silicones. The use of such preformed silicone emulsions is preferred for ease of processing and control of silicone particle size. Such pre-formed silicone emulsions will typically additionally comprise a

[0155] 5 suitable emulsifier such as an anionic or nonionic emulsifier, or mixture thereof, and may be prepared by a chemical emulsification process such as emulsion polymerisation, or by mechanical emulsification using a high shear mixer. Pre-formed silicone emulsions having a Sauter mean droplet diameter (D3,2) of less than 0.15 micrometers are generally termed microemulsions.

[0156] 10

[0157] Examples of suitable pre-formed silicone emulsions include emulsions DC2-1766, DC2- 1784, DC-1785, DC-1786, DC-1788 and microemulsions DC2-1865 and DC2-1870, all available from Dow Corning. These are all emulsions / microemulsions of dimethiconol. Also suitable are amodimethicone emulsions such as DC2-8177 and DC939 (from Dow Corning)

[0158] 15 and SME253 (from GE Silicones).

[0159] Also suitable are silicone emulsions in which certain types of surface active block copolymers of a high molecular weight have been blended with the silicone emulsion droplets, as described for example in WO03 / 094874. In such materials, the silicone

[0160] 20 emulsion droplets are preferably formed from polydiorganosiloxanes such as those described above. One preferred form of the surface active block copolymer is according to the following formula:

[0161] HO(CH2CH2O)x(CH(CH3)CH2O)y(CH2CH2O)x H

[0162] 25 wherein the mean value of x is 4 or more and the mean value of y is 25 or more. Another preferred form of the surface active block copolymer is according to the following formula:

[0163] 30 (HO(CH2CH2O)a(CH(CH3)CH2O)b)2-N-CH2-CH2-N((OCH2CH(CH3))b(OCH2CH2)aOH)2 wherein the mean value of a is 2 or more and the mean value of b is 6 or more.

[0164] Mixtures of any of the above described silicone emulsions may also be used. P0001170WQ

[0165] - 14 -

[0166] The above described silicone emulsions will generally be present in a composition of the invention at levels of from 0.05 to 10%, preferably 0.05 to 5%, more preferably from 0.5 to 2% by total weight of silicone based on the total weight of the composition.

[0167] 5 Further Ingredients

[0168] The composition is free from parabens. The compositions of the invention preferably comprise a preservative. The preservative is preferably selected from sodium benzoate, phenoxyethanol, capryl glycol, benzyl alcohol, sorbate salts, hexanediol, DMDMH and mixtures thereof, more preferably selected from sodium benzoate, phenoxyethanol,

[0169] 10 capryl glycol, benzyl alcohol, sorbate salts, hexanediol, and mixtures thereof. Most preferably the composition comprises sodium benzoate.

[0170] A chelating agent, such as EDTA may also be used.

[0171] 15 The conditioners of the invention preferably comprise a pH adjuster.

[0172] The pH adjuster may be selected from selected from lactic acid, citric acid, hydrochloric acid, acetic acid, tartaric acid, fumaric acid, malic acid, succinic acid, glycolic acid, sodium hydroxide and mixtures thereof, preferably lactic acid, citric acid, acetic acid,

[0173] 20 tartaric acid, fumaric acid, malic acid, succinic acid, glycolic acid, and mixtures thereof.

[0174] Most preferred acids are selected from citric acid, lactic acid, and mixtures thereof.

[0175] A composition of the invention may contain other ingredients for enhancing performance

[0176] 25 and / or consumer acceptability. Such ingredients include fragrance, dyes and pigments, pH adjusting agents, pearlescers or opacifiers, viscosity modifiers, for example polypropylene glycol, and preservatives or antimicrobials. Each of these ingredients will be present in an amount effective to accomplish its purpose. Generally these optional ingredients are included individually at a level of up to 5% by weight of the total

[0177] 30 composition.

[0178] Hair treatment compositions of the invention are primarily intended for topical application to the hair and / or scalp of a human subject, either in rinse-off or leave-on compositions, for the treatment of dry, damaged and / or unmanageable hair. P0001170WG

[0179] - 15 -

[0180] The invention will be further illustrated by the following, non-limiting Example, in which all percentages quoted are by weight based on total weight unless otherwise stated.

[0181] EXAMPLES

[0182] The Hair

[0183] Virgin: The hair used in the following examples was dark brown European hair tresses 5 grams and 25 cm long.

[0184] Bleached: Virgin hair tresses were bleached according to the following protocol.

[0185] Each switch of hair was bleached for 30 min with Universal Bleach Powder (ex Bright International Corp) and Wella Welloxon 12 Perfect 40 Vol Creme Developer (ex Salons Direct) (12g of Powder mixed with 24g Creme Peroxide per switch- a ratio of Creme Peroxide: Powder 2:1). Hair was then rinsed with water for 2 minutes and dried. This procedure was repeated on the same hair to produce twice bleached hair.

[0186] The double-bleached hair was dialysed prior to the experiments in 5L of distilled water over a period of 72 hours, and the water was changed 3 times over this period. After dialysing, the hair tresses were left to dry overnight in a controlled environment (20°C and 50% relative humidity).

[0187] The Compositions

[0188] Compositions 1 to 3 are shampoos in accordance with the invention comprising MSG and sodium benzoate.

[0189] A is a comparative example comprising MSG and methyl paraben / DMDM hydantoin. This example is representative of the prior art in claim 1 of US4975274.

[0190] P0001170WC

[0191] - 16 -

[0192] Table 1 : Ingredients (wt%) of Compositions 1 and 2 in accordance with the invention

[0193] P0001170WC

[0194] - 17 -

[0195] Table 2: Ingredients (wt%) of Compositions 3 in accordance with the invention and comparative composition A (all amounts at 100 % activity unless otherwise stated) ie 9.5 % @ 100 % active

[0196] 5 Treatment of the Hair

[0197] Hair (double-bleached) was treated with the above compositions using the following method:

[0198] The hair was washed with the test shampoos using 0.1 ml / 1 g hair applied and lathered for

[0199] 10 30 seconds followed by 30 seconds rinse in tap water.

[0200] The hair tresses were then left to dry overnight at 20°C, 50% relative humidity. P0001170WG

[0201] - 18 -

[0202] Measurement of Differential Scanning Calorimetry (DSC)

[0203] In order to prepare hair samples for Differential Scanning Calorimetry (DSC), 1 inch of hair was cut from each tress. Hair was then chopped into 1-2 mm sections.

[0204] Measurements were performed using a Mettler-Toledo DSC (with auto-sampler). 7-10 mg samples of dry, finely chopped hair was placed in the 'Medium Pressure Stainless Steel DSC Pans' and accurately weighed. 50 microlitres of deionised water was then added to each sample after which the pan lid was put on and the pans crimped shut to provide a hermetic seal. Pans were equilibrated for a minimum of 24 h ahead of any measurement to allow the hair to fully hydrate. The DSC was programmed to first heat each sample to 100 °C for 3 min and then to warm them further from 100 to 180 °C at a constant rate of 5 °C min'.

[0205] Table 3: Mean denaturation temperatures and change in denaturation temperature for treatment over successive five wash cycles for virgin and bleached hair treated with Composition 3 in accordance with the invention and Comparative Composition A.

[0206] It will be seen that bleached hair treated with Composition 3 comprising MSG and sodium benzoate in accordance with the invention provide a higher increase in the denaturation temperature after 5 wash cycles, than bleached hair treated with Compositions A comprising MSG and methyl paraben / DMDM hydantoin.

Claims

P0001170WQ- 19 -CLAIMS1. A hair cleansing composition, comprising: i) 0.2 to 2.5 wt %, preferably from 0.5 to 2 wt %, of a glutamate salt, preferably sodium glutamate, most preferably monosodium glutamate; and ii) a cleansing surfactant; wherein the pH is in the range of from 4.1 to 6, preferably 4.1 to 5, most preferably4.1 to less than 5; and wherein the composition is free from parabens.

2. The composition as claimed in claim 1, wherein the glutamate salt is selected from sodium glutamate, potassium glutamate, magnesium diglutamate, calcium diglutamate, ammonium glutamate and mixtures thereof.

3. The composition as claimed in claim 2 wherein the glutamate salt is sodium glutamate.

4. The composition as claimed in claim 3, wherein the sodium glutamate is monosodium glutamate.

5. The composition as claimed in any preceding claim, wherein the amount of glutamate salt is from 0.5 to 2 wt %, by weight of the total composition.

6. The composition as claimed in any preceding claim comprising lactic acid, citric acid, acetic acid, tartaric acid, fumaric acid, malic acid, succinic acid, glycolic acid, and mixtures thereof, preferably lactic acid, citric acid or mixtures thereof.

7. The composition as claimed in any preceding claim, wherein the pH is in the range of from 4.1 to 5, preferably 4.1 to less than 5.P0001170WQ- 20 -8. A composition according to any preceding claim, which further comprises a silicone in an amount of 0.5 to 6.5 wt %.

9. The composition as claimed in any preceding claim, which comprises a polymeric deposition aid.

10. The composition as claimed in any preceding claim, which comprises a preservative selected from sodium benzoate, phenoxyethanol, capryl glycol, benzyl alcohol, sorbate salts, hexanediol, DMDMH and mixtures thereof.

11. A method of repairing damaged hair comprising the step of applying to the hair a composition as defined in any of claims 1 to 10.

12. Method as claimed in claim 11 , wherein the hair is bleached.

13. Method as claimed in claim 11 or claim 12, wherein the composition is applied to the hair multiple times, to give progressive damage repair, preferably a progressive increase in the denaturation temperature of the protein.

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