WO2025078219A1

WO2025078219A1 - Hair conditioner composition

Info

Publication number: WO2025078219A1
Application number: PCT/EP2024/077625
Authority: WO
Inventors: Fraser Ian Bell; Robert Wayne Dawson; Julie Marie ROBERTS; Stephen John Singleton
Original assignee: Unilever Global IP Ltd; Unilever IP Holdings BV; Conopco Inc
Current assignee: Unilever Global IP Ltd; Unilever IP Holdings BV; Conopco Inc
Priority date: 2023-10-13
Filing date: 2024-10-01
Publication date: 2025-04-17
Anticipated expiration: 2026-04-13
Also published as: AR134081A1

Abstract

A conditioner composition comprising: (a) a conditioning gel phase comprising a cationic conditioning surfactant and a fatty material; and (b) a blend of amino acids consisting of (i) arginine, (ii) glutamic acid and (iii) serine, gives surprising increase in denaturation temperature of hair protein, where the is hair selected from wavy hair and curly hair; the composition being free from other amino acids.

Description

HAIR CONDITIONER COMPOSITION

Field of the Invention

The present invention relates to a treatment composition for wavy or curly hair, comprising mixtures of amino acids, its use to fortify (repair or strengthen) wavy or curly hair, and a method of treating wavy or curly hair using said composition.

Background of the Invention

Consumers regularly subject their hair to intensive treatment, care, and styling routines to help achieve their desired look. The actions performed by consumers introduce modifications to the chemistry of hair keratin protein which results in micro- and macro-structural changes, including loss of proteins and amino acids, and in turn, changes fibre physical properties: the consequences of these are generally perceived by the consumer as damage.

Hair is composed mainly of proteins, specifically keratins. Differential Scanning Calorimetry (DSC) can be used to measure the denaturation temperature of the internal hair proteins. The higher the temperature required to “melt” hair protein (ie the more energy that is required) the stronger and more stable the protein structure is. A decrease in the denaturation temperature of internal hair proteins is an indicator that the proteins have been damaged and that loss of bonds, including hydrogen bonds, and loss of crystalline molecular structure has occurred. Therefore, an increase in denaturation temperature of hair is desirable. This indicates strengthening of hair and/or repair of damage by formation of bonds and increased stability, molecular structure and crystallinity of the proteins.

The level of damage can be measured by the degree of reduction in the denaturation temperature following a damaging treatment. Conversely, the level of repair or strengthening is indicated by the size of the increase of the denaturation temperature with treatments designed for this purpose. Treatments are known which address the problem of hair damage due to chemical hair treatments, and which may involve the use of amino acids. WO 2018/065237 and WO 2018/065248, disclose the use of glutamic acid with proline and aniline to provide improved damage repair as evidenced by an increase in the denaturation temperature of bleached hair. WO 00/51556 discloses a hair care composition comprising four or more amino acids where each amino acid is selected from a different group of amino acids. The composition aims to treat hair that is subjected to a wide range of insults that can cause weakening and damage. KR2019 0041626 discloses compositions that comprise an amino acid complexes that may include any one or more of lysine, histidine, arginine, aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, methionine, leucine, tyrosine, phenylalanine or cysteine, at 0.3 to 5 parts by weight. The compositions can be applied to hair prior to perming.

However, we have found that not all amino acids are equally lost due to damage or are equally restored. Further, the content of lost amino acids depends upon the type of hair itself.

Hair is often defined by it’s natural shape.

Wavy hair (also known as type 2 hair) has curls that are in a loose “S” pattern.

Curly hair (also known as type 3 hair) has loose to corkscrew curls which are typically defined as a “round S”.

There remains a need for more effective treatments for wavy and curly hair which deliver fortification benefits, such as repair or strengthening, during every day hair-care regimes.

We have found that wavy or curly hair has specific requirements for damage repair.

We have now found that a mixture of specific amino acids, namely glutamic acid, serine and arginine, in a conditioner, can advantageously increase the denaturation temperature of wavy and curly hair. Surprisingly, the conditioner vehicle is crucial for achieving successful increase in denaturation temperature.

Summary of the Invention

In a first aspect, the invention provides a conditioner composition comprising:

(1) a conditioning gel phase comprising:

(a) a cationic conditioning surfactant; and

(b) a fatty material; and

(2) a blend of amino acids consisting of (i) arginine, (ii) glutamic acid and (iii) serine; the composition being free from other amino acids.

A second aspect of the invention provides a method of increasing the denaturation temperature of the internal proteins of hair selected from wavy hair and curly hair, comprising the step of applying to the hair a composition of the first aspect. The increase in denaturation temperature is compared with the same composition that does not comprise a blend of amino acids consisting of (i) arginine, (ii) glutamic acid and (iii) serine.

Preferably the method comprises an additional step of rinsing the composition from the hair.

The method preferably additionally comprises the step of leaving the composition on the 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.

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 proteins of the hair.

In one embodiment, the hair is virgin hair. 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, reducing treatment, heat treatment and strong and/or prolonged exposure to solar radiation; nor displays features characteristic of damaged hair, for example, split ends and/or excessive dryness and/or increased surface friction compared with hair that has sustained low level damage. Virgin hair includes hair that has sustained low levels of damage during the natural hair life cycle. Sources of low level damage likely include but are not necessarily limited to, washing, brushing, combing and natural processes such as limited solar photo-degradation for example. That is to say no intensive physical and/or chemical treatment has been applied.

In this way, it is possible to increase the denaturation temperature of the protein to higher than that of virgin hair. This indicates an increase in strength of the virgin hair.

A third aspect of the invention provides a use of a blend of arginine, glutamic acid and serine to increase the denaturation temperature of the internal proteins of hair selected from wavy hair and curly hair. Preferably, the blend of arginine, glutamic acid and serine is present in a composition of the first aspect. In the uses of the invention, the increase in denaturation temperature is compared with the same composition that does not comprise a blend of amino acids consisting of (i) arginine, (ii) glutamic acid and (iii) serine. Detailed Description of the Invention

Compositions in accordance with the invention are preferably formulated as conditioners for the treatment of hair (typically after shampooing) and subsequent rinsing.

Each amino acid can be added separately at different stages, during the manufacture of the compositions of the invention, or the same stage, for example as a premix. Alternatively, 2 or 3 of the amino acids can be premixed before addition. They can be added, for example, as a dispersion in water or combined with the fragrance oil.

General description of the invention

The amino acids (b)

The amino acids for use the compositions of the invention are (i) arginine, (ii) glutamic acid and (iii) serine. The composition is free from other amino acids; the composition does not comprise other amino acids in addition to the blend (b).

The amino acid mixture is preferably used in solution or emulsified form. It may be dissolved or dispersed in a suitable solvent or carrier.

The amount of the amino acid mixture in a hair composition is preferably from 0.1 wt % to 10 wt %, more preferably from 0.2 wt % to 5 wt %, most preferably from 0.25 wt % to 2 wt %, by total weight of the composition.

The weight ratio of glutamic acid : arginine : serine is preferably 2:1 :1 to 1 :2:1 to 1 :1 :2, more preferably 1 :1 :1.

Amino acids, including (i) arginine, (ii) glutamic acid and (iii) serine are available from many suppliers, for example Kusuma Pharma and Ajinomoto co Inc.

The conditioner composition

Preferably, the treatment composition is selected from a rinse-off hair conditioner, a hair mask, a leave-on conditioner composition, and a pre-treatment composition, more preferably selected from a rinse-off hair conditioner, a hair mask, a leave-on conditioner composition, and a pretreatment composition, for example an oil treatment, and most preferably selected from a rinse- off hair conditioner, a hair mask and a leave-on conditioner composition. The treatment composition is preferably selected from a rinse-off hair conditioner and a leave-on conditioner. Rinse off conditioners for use in the invention are conditioners that are typically left on wet hair for 1 to 2 minutes before being rinsed off.

Hair masks for use in the present invention are treatments that are typically left on the hair for 3 to 10 minutes, preferably from 3 to 5 minutes, more preferably 4 to 5 minutes, before being rinsed off.

Leave-on conditioners for use in the invention are typically applied to the hair and left on the hair for more than 10 minutes, and preferably are applied to the hair after washing and not rinsed out until the next wash.

The conditioning base comprises a cationic conditioning surfactant and a fatty material.

The composition according to the invention comprises one or more conditioning surfactants which are cosmetically acceptable and suitable for topical application to the hair.

Suitable conditioning surfactants are selected from cationic surfactants, used singly or in admixture. Examples include quaternary ammonium cationic surfactants corresponding to the following general formula:

[N(R1)(R2)(R3)₍R4_{)]+ (X)}- in which R R2, R3, and R^ are each independently selected from (a) an aliphatic group of from 16 to 22 carbon atoms, or (b) an aromatic, alkoxy, polyoxyalkylene, alkylamido, hydroxyalkyl, aryl or alkylaryl group having up to 22 carbon atoms; and X is a salt-forming anion such as those selected from halide, (e.g. chloride, bromide), acetate, citrate, lactate, glycolate, phosphate nitrate, sulphate, and alkylsulphate, for example methosulphate, radicals.

The aliphatic groups can contain, in addition to carbon and hydrogen atoms, ether linkages, and other groups such as amino groups. The aliphatic groups, e.g., those of about 12 carbons, or higher, can be saturated or unsaturated.

Specific examples of such quaternary ammonium cationic surfactants of the above general formula are cetyltrimethylammonium chloride, behenyltrimethylammonium chloride (BTAC), cetylpyridinium chloride, tetramethylammonium chloride, tetraethylammonium chloride, octyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octyldimethylbenzylammonium chloride, decyldimethylbenzylammonium chloride, stearyldimethylbenzylammonium chloride, didodecyldimethylammonium chloride, dioctadecyldimethylammonium chloride, tallowtrimethylammonium chloride, cocotrimethylammonium chloride, dipalmitoylethyldimethylammonium chloride, PEG-2 oleylammonium chloride and salts of these, where the chloride is replaced by other halide (e.g., bromide), acetate, citrate, lactate, glycolate, phosphate nitrate, sulphate, or alkylsulphate.

In a preferred class of cationic surfactant of the above general formula, R1 is a C16 to C22 saturated or unsaturated, preferably saturated, alkyl chain and R², R3 and R⁴ are each independently selected from CH3 and CH2CH2OH, preferably CH3.

Specific examples of such preferred quaternary ammonium cationic surfactants are cetyltrimethylammonium chloride (CTAC), behenyltrimethylammonium chloride (BTAC) and mixtures thereof.

Preferably, the quaternary ammonium cationic surfactant has a cation selected from cetyltrimethylammonium and behenyltrimethylammonium.

Alternatively, primary, secondary or tertiary fatty amines may be used in combination with an acid to provide a cationic surfactant suitable for use in the invention. The acid protonates the amine and forms an amine salt in situ in the hair care composition. The amine is therefore effectively a non-permanent quaternary ammonium or pseudo-quaternary ammonium cationic surfactant.

Suitable fatty amines of this type include amidoamines of the following general formula:

R¹-C(O)-N(H)-R²-N(R³)(R⁴) in which R1 is a fatty acid chain containing from 12 to 22 carbon atoms, R² is an alkylene group containing from one to four carbon atoms, and R³ and R⁴ are each independently, an alkyl group having from one to four carbon atoms. Specific examples of suitable materials of the above general formula are stearamidopropyldimethylamine, stearamidopropyldiethylamine, stearamidoethyldiethylamine.stearamidoethyldimethylamine, palmitamidopropyldimethylamine, palmitamidopropyldiethylamine, palmitamidoethyldiethylamine, palmitamidoethyldimethylamine, behenamidopropyldimethylamine, behenamidopropyldiethylamine, behenamidoethyldiethylamine, behenamidoethyldimethylamine, arachidamidopropyldimethylamine, arachidamidopropyldiethylamine, arachidamidoethyldiethylamine, arachidamidoethyldimethylamine, and diethylaminoethylstearamide.

Also useful are dimethylstearamine, dimethylsoyamine, oyamine, myristylamine, tridecylamine, ethylstearylamine, N-tallowpropane diamine, ethoxylated (with 5 moles of ethylene oxide) stearylamine, dihydroxyethylstearylamine, and arachidyl behenylamine.

Particularly preferred is stearamidopropyldimethylamine.

The conditioning surfactant is present in the composition in a concentration of 0.1 to 10%, preferably at least 0.5%, more preferably at least 1%, still more preferably at least 2%, even more preferably at least 3% or even at least 4% but typically not more than 9%, preferably not more than 8%, more preferably not more than 7%, still more preferably not more than 6%, even more preferably not more than 5% by weight of the composition.

The fatty material

The compositions of the invention comprise a fatty material. Preferably the fatty material is a fatty acid or a fatty alcohol, most preferably a fatty alcohol. Preferred fatty materials have a carbon-carbon chain length of from Cs to C22.

The combined use of fatty alcohols and cationic surfactants in conditioning compositions is preferred because this leads to the formation of a lamellar phase, in which the cationic surfactant is dispersed.

The fatty material comprises from 8 to 22 carbon atoms, preferably 16 to 22, most preferably C16 to C18. Fatty alcohols are typically compounds containing straight chain alkyl groups. Preferably, the alkyl groups are saturated. Examples of preferred 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 for use in the invention. The level of fatty material in conditioners for use in 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% by weight of the composition.

The weight ratio of cationic-surfactant to fatty material 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.

A preferred conditioner comprises a conditioning gel phase having little or no vesicle content. Such conditioners and methods for making them are described in WO2014/016354, WO2014/016353, WO2012/016352 and WO2014/016351.

Such a conditioning gel phase comprises, by total weight of the composition, i) from 0.4 to 8 wt % of fatty alcohol having from 8 to 22 carbons, ii) from 0.1 to 2 wt % of cationic surfactant, and the composition confers a Draw Mass of from 1 to 250 g, preferably 2 to 100 g, more preferably 2 to 50 g, even more preferably 5 to 40 g and most preferably 5 to 25 g to hair treated with the composition.

Draw Mass is the mass required to draw a hair switch through a comb or brush. Thus the more tangled the hair the greater the mass required to pull the switch through the comb or brush, and the greater the level of condition of the hair, the lower the Draw Mass.

The Draw Mass is the mass required to draw a hair switch, for example of weight 1 to 20 g, length 10 to 30 cm, and width 0.5 to 5 cm through a comb or brush, as measured by first placing the hair switch onto the comb or brush, such that from 5 to 20 cm of hair is left hanging at the glued end of the switch, and then adding weights to the hanging end until the switch falls through the comb or brush.

Preferably, the hair switch is of weight 1 to 20 g, more preferably 2 to 15 g, most preferably from 5 to10 g. Preferably, the hair switch has a length of from 10 to 40 cm, more preferably from 10 to 30 cm, and a width of from 0.5 to 5 cm, more preferably from 1.5 to 4 cm.

Most preferably, the Draw Mass is the mass required to draw a hair switch, for example of weight 10 g, length 20 cm, and width 3 cm through a comb or brush, as measured by first placing the hair switch onto the comb or brush, such that from 20 cm of hair is left hanging at the glued end of the switch, and then adding weights to the hanging end until the switch falls through the comb or brush.

Preferably, the composition of the invention comprises a preservative. Illustrative preservatives for use include sodium benzoate, iodopropynyl butyl carbamate, phenoxyethanol, hydroxyacetophenone, ethylhexylglycerine, methyl paraben, propyl paraben, imidazolidinyl urea, sodium dehydroacetate, dimethyl-dimethyl (DMDM) hydantoin, potassium sorbate, sodium salicylate, levulinic acid, ansic, acid, and benzyl alcohol, or a combination thereof. Other preservatives suitable for use include sodium dehydroacetate, chlorophenesin, and decylene glycol. Preservatives are preferably employed in amounts of 0.01% to 2.0%, more preferably 0.05 to 1 wt %, by weight of the total weight of hair treatment composition. Preferably the preservative is an organic acid, most preferably sodium benzoate. Preferably it is used at a level of 0.01% to 2.0%, more preferably 0.05 to 1 wt %, most preferably from 0.1 to 0.7 wt %, by total weight of the composition. It may be used in conjunction with disodium EDTA, preferably at a ratio of sodium benzoate to EDTA of 10:1.

A preferred composition has a pH of from 3 to 5.8, preferably 4 to 5.

The composition of the invention preferably comprises a pre-formed emulsified silicone. Mixtures of emulsified silicones can be used.

Suitable silicones include polydiorganosiloxanes, in particular polydimethylsiloxanes which have the CTFA designation dimethicone. Also suitable for use compositions of the invention 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 96/31188.

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

Emulsified silicones for use in the compositions of the invention will typically have a D90 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 (D50) of 0.15 micron are generally termed microemulsions.

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

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 emulsified silicones for inclusion in compositions 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).

Suitable quaternary silicone polymers are described in EP-A-0 530 974. A preferred quaternary silicone polymer is K3474, ex Goldschmidt.

Also suitable are emulsions of amino functional silicone oils with non ionic and/or cationic surfactant.

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).

Preferably, the silicone is selected from the group consisting of dimethicone, dimethiconol, amodimethicone and mixtures thereof. Also preferred are blends of amino-functionalised silicones with dimethicones. The amount of silicone in compositions of the invention may suitably range from 0.05 to 10%, preferably from 0.1 to 8%, more preferably 0.5 to 6.5 %, most preferably 0.6 to 3 % at 100 % activity, based on the total weight of the composition).

The composition of the invention preferably includes at least one inorganic electrolyte. The inorganic electrolyte provides viscosity to the composition. It is intended that the inorganic electrolyte is separate from any inorganic electrolytes that may be present in the raw materials of the invention.

Suitable inorganic electrolytes include metal chlorides (such as sodium chloride, potassium chloride, calcium chloride, magnesium chloride, zinc chloride, ferric chloride and aluminium chloride) and metal sulfates (such as sodium sulfate and magnesium sulfate. Preferred inorganic electrolytes for use in the invention include sodium chloride, potassium chloride, magnesium sulfate and mixtures thereof.

The amount of inorganic electrolyte in compositions of the invention preferably ranges from 0.5 to 10 %, more preferably from 0.75 to 7 %, even more preferably from 1 to 5 % and most preferably from 1 to 3 % (by weight based on the total weight of the composition).

A composition of the invention may contain other ingredients for enhancing performance and/or consumer acceptability. Such ingredients include, for example, fragrance, dyes and pigments, pH adjusting agents (for examples organic acids, sodium hydroxide), pearlescers, opacifiers, viscosity modifiers, 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 composition.

For the avoidance of doubt the word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of.” In other words, the listed steps, options, or alternatives need not be exhaustive.

The disclosure of the invention as found herein is to be considered to cover all aspects as found in the claims as being multiply dependent upon each other irrespective of the fact that claims may be found without multiple dependency or redundancy. Unless otherwise specified, numerical ranges expressed in the format "from x to y" are understood to include x and y. In specifying any range of values or amounts, any particular upper value or amount can be associated with any particular lower value or amount. All percentages and ratios contained herein are calculated by weight unless otherwise indicated. The various features of the present invention referred to in individual sections above apply, as appropriate, to other sections mutatis mutandis. Consequently, features specified in one section may be combined with features specified in other sections as appropriate. Any section headings are added for convenience only and are not intended to limit the disclosure in any way.

Unless otherwise indicated, ratios, percentages, parts, and the like, referred to herein, are by weight.

B

Two comparative examples were prepared as follows:

Shampoo B: Shampoo comprising glutamic acid, serine and arginine

Shampoo A: The same as Shampoo B, only without the amino acids.

Table 1 : Compositions of Shampoo A and Shampoo B

The shampoos A and B were prepared using the following method:

1. In the compositions in accordance with the invention, the amino acids were added to water in a suitable vessel, with stirring.

2. Carbomer, SPES and CAPB were then added.

3. The mixture was heated to 30° C and mixed until homogenous.

4. Guar polymer was then added and mixed.

5. Glycerin and PEG-45M, fragrance, silicone and preservatives and any other ingredients were added.

6. The pH was adjusted to pH 4 to 5.

7. Salt and polypropylene glycol were then added to adjust the viscosity as desired.

1, in accordance with the invention and

The following examples were prepared:

Conditioner 1: Conditioner comprising glutamic acid, serine and arginine.

Conditioner A: The same as Conditioner 1 , but without the amino acids.

Table 2: Compositions of Conditioner 1, in accordance with the invention and comparative Conditioner A

The conditioners were prepared using the following method:

1. Water was added to a suitable vessel and heated to 80 °C.

2. Cetearyl alcohol was then added along with tertiary amine salt (TAS).

3. The formulation was allowed to cool and BTAC was added with mixing until opaque and thick.

4. Lactic acid was added and the formulation was stirred for a further 10 minutes to ensure protonation of the TAS.

5. The heat was then turned off and quench water added.

6. The amino acids were added.

7. The mixture was then cooled to below 55°C and the preservatives and NaCI were added.

8. The rest of the materials were then added.

9. Finally the formulation was mixed at high shear for 5 minutes.

Example 3: Treatment of hair with Comparative Shampoos 1 and 2, Conditioner Composition 1 , in accordance with the invention and Comparative Conditioner A

Treatment of hair

Naturally curly hair (Type 3) was used that had not been subjected to chemical treatments including bleaching, colouring, perming or straightening. The hair used was dark brown European hair, in switches of 5g weight. This is referred to as Virgin hair.

Hair was treated with shampoo compositions (given above) using the following method:- The hair fibres were held under running water for 30 seconds, shampoo applied at a dose of 0.1 g of shampoo per 1 g of hair and rubbed into the hair for 30 seconds. Excess lather was removed by holding under running water for 30 seconds and the shampoo stage repeated. The hair was rinsed under running water for 1 minute. This was repeated as required.

Conditioner only

Hair was treated with conditioner compositions (given above) using the following method:- The hair fibres were held under running water for 30 seconds, conditioner applied at a dose of 0.2 g of conditioner per 1 g of hair and rubbed into the hair for 1 minute. The hair was then rinsed under running water for 1 minute. This was repeated as required.

The denaturation temperature of the hair was measured before and after treatment. The results are given in Tables 3 and 4. Table 3: Denaturation temperature of curly hair before treatment and after treatment with Shampoo A and Shampoo B, for 5 washes and 10 washes

Same letters indicate no significant difference

It will be seen that whilst both shampoos confer an increase in denaturation temperature after 5 and 10 washes, no significant difference is apparent between hair treated with shampoo A (with no amino acids) and shampoo B (with amino acids glutamic acid, serine and arginine).

Table 4: Denaturation temperature of curly hair before treatment and after treatment with Conditioner 1 and Conditioner A, for 5 washes

It will be seen that whilst both conditioners confer an increase in denaturation temperature after

5 washes, Conditioner 1 , in accordance with the invention, provides a significantly higher increase than that conferred by the comparative Conditioner A, which did not comprise any amino acids.

Example 4: Commerically available conditioner product, representative of the prior art The commercially available hair conditioner product, Lux CD Bath Glow Straight & Shine, comprising multiple amino acids, was obtained.

The ingredients given on the pack are as follows:

Water, stearyl alcohol, glycerin, dimethicone, behentrimonium chloride, DPG, paraffin, amodimethicone, lactic acid, C12-14 sec-pareth-7, EDTA-2Na, cetrimonium chloride, PEG-7 propylheptyl ether, C12-14 sec-pareth-5, tocopheryl acetate, acetic acid, PEG-180M, hydrolyzed keratin pg-propyl methylsilanediol, butylene glycol, steardimonium hydroxypropyl hydrolyzed keratin, PCA-Na, sodium lactate, Tremella fuciformis polysaccharide, ectoin, betaine, arginine, ethanol, aspartic acid, taurine, PCA, alanine, glycine, serine, valine, proline, threonine, lysine HCI, histidine HCI, isleucine, glutamic acid, phenylalanine, leucine, histidine, allantoin, glutamine, tyrosine, cystine, cysteine, tryptophan, methionine, sodium benzoate, phenoxyethanol, iodopropynyl butylcarbamate, potassium sorbate, fragrance.

The product was used to treat curly hair. The hair was as described in Example 3 above, and the “Conditioner only” protocol was used to treat the hair.

The denaturation temperature of the hair was measured before and after treatment. The results are given in Table 5:

Table 5: Denaturation temperature of hair before treatment and after treatment with Conditioner of the prior art

Same letters indicate no significant difference between Td

No significant difference is apparent after 5 washes with Lux CD Bath Glow Straight & Shine.

Claims

1. A conditioner composition comprising:

(I) a conditioning gel phase comprising:

(a) a cationic conditioning surfactant;

(b) a fatty material;

(II) a blend of amino acids consisting of (i) glutamic acid (ii) arginine and (iii) serine; and the composition is free from other amino acids.

2. Composition as claimed in claim 1 , wherein the weight ratio of (i): (ii): (iii) is 2:1:1 to 1 :2:1 to 1 :1 :2.

3. Composition as claimed in claim 1 or claim 2, wherein the blend of amino acids is present in an amount of from 0.1 to 10 % by weight of the total composition.

4. Composition as claimed in any preceding claim, which comprises a preservative, which is preferably sodium benzoate.

5. A method of increasing the denaturation temperature of the internal proteins of hair selected from wavy hair and curly hair, comprising the step of applying to the hair a composition as defined in any one of claims 1 to 4 compared with the same composition that does not comprise a blend of amino acids consisting of (i) glutamic acid (ii) arginine and (iii) serine.

6. A method as claimed in claim 5, which additionally comprises the step of leaving the composition on the hair for 2 seconds to 20 minutes, preferably 10 seconds to 3 minutes, most preferably 20 seconds to 1 minute.

7. A method as claimed in claim 5 or claim 6, which additionally comprises the step of repeating the application of the composition to the hair.

8. A method as claimed in claim 7 wherein 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.

9. A method as claimed in any one of claims 5 to 8, in which the hair is virgin hair.

10. Use of a blend consisting of arginine, glutamic acid and serine to increase the denaturation temperature of the internal proteins of hair selected from wavy hair and curly hair, compared with the same composition that does not comprise a blend of amino acids consisting of arginine, glutamic acid and serine.

11. Use of a blend consisting of arginine, glutamic acid and serine in a composition as defined in any of claims 1 to 4 to increase the denaturation temperature of the internal proteins of hair selected from wavy hair and curly hair compared with the same composition that does not comprise a blend of amino acids consisting of arginine, glutamic acid and serine.

12. A use as claimed in any one of claims 10 to 11, in which the hair is virgin hair.