WO2003092639A1

WO2003092639A1 - Hair conditioning compositions containing silicone blend

Info

Publication number: WO2003092639A1
Application number: PCT/EP2003/003360
Authority: WO
Inventors: Nicholas John Ainger; Neil Scott Shaw; Ruby Loo Bick Tan-Walker; Stephen Lee Wire
Original assignee: Unilever Plc; Unilever Nv; Hindustan Lever Limited
Priority date: 2002-05-03
Filing date: 2003-03-31
Publication date: 2003-11-13
Also published as: GB0210246D0; AU2003215679A1

Abstract

Hair treatment compositions for cleansing and conditioning the hair or scalp containing a cleansing surfactant and a silicone component comprising droplets of silicone blend with a mean diameter greater than 5 micrometres, the silicone blend comprising a first silicone having a viscosity of less than 100,000 mm2sec-1 at 25°C, and a second silicone which is functionalised.

Description

HAIR CONDITIONING COMPOSITIONS CONTAINING SILICONE BLEND

TECHNICAL FIELD

This invention relates to hair treatment compositions containing particular types of silicone blends which provide the composition with conditioning benefits. In particular it is concerned with shampoo or shower-gel compositions which also provide a conditioning benefit.

BACKGROUND AND PRIOR ART

The use of silicones as conditioning agents in hair treatment compositions is well known, and widely documented in the patent literature. Generally, dispersed droplets of silicone are suspended in the composition which, when applied to the hair, deposits the silicone material on the hair shaft resulting in the formation of a film. Whilst their use gives good conditioning, for example wet comb properties, there is a need to further improve the conditioning behaviour of hair treatment compositions, particularly shampoo compositions which also contain cleansing surfactants. The presence of such cleansing surfactants in a composition can lead to a reduction in the deposition of silicone onto the hair.

Moreover, silicones are expensive ingredients compared to many other components, and there is a need to obtain a higher level of conditioning without the use of higher levels of silicones in hair treatment compositions. Furthermore, certain negatives are associated with silicones for some consumers . Repeated use of compositions with high levels of silicones can lead to a build up of silicone on the hair and undesirable effects such as a heavy, oily feel to the hair.

There is therefore the need for hair treatment compositions which can provide conditioning benefits to the hair (i.e. reduction in friction of the hair when wet and/or dry) with lower levels of silicone than conventionally used. Alternatively, there is a need for hair treatment compositions which provide improved conditioning for the same level of silicone in the composition.

W099/44565 and W099/44567 (Unilever) disclose shampoo compositions containing a combination of an amino- functionalised silicone and an insoluble non-amino functional insoluble silicone. In W099/44565, the particle size of the non-amino functional silicone is less than 2 micrometres. In W099/44567, the non-amino functional

2 -1 silicone has a viscosity of at least 500,000 cSt (mm sec ).

In both documents, the two silicone components are incorporated into the shampoo composition as separate emulsions .

W099/49836 (Unilever) discloses rinse-off conditioner formulations containing an amino-functional silicone corresponding to a defined general formula and having a mole percent amino functionality of at least 1 mole %. The formulations may further comprise emulsified particles of a non-amino functionalised silicone. W099/53889 (Unilever) discloses shampoo compositions containing emulsified particles of a first insoluble silicone having a particle size of from 0.15 to 30 micrometres and a second insoluble silicone having a particles size less than 0.10 micrometres. The silicones are incorporated into the shampoo as preformed aqueous emulsions .

W097/12594 (L'Oreal) describes hair compositions containing at least one silicone-grafted polymer with a polysiloxane backbone grafted by non-silicone organic monomers and at least one silicone selected from silicones containing a quaternary amine function, silicone resins and silicone gums .

US 6,028,041 (L'Oreal) and EP 0 811 371 (L'Oreal) disclose the use of a mixture of at least one aminated silicone and at least one insoluble silicone of viscosity less than or

2 -1 equal to 100 Pa.s at 25°C (100,000 cSt = 100,000 mm sec ) in conditioning hair-care compositions. The two silicones are added as separate components.

W098/18443 (Procter & Gamble) discloses shampoo compositions containing a first non-volatile conditioning agent of particle size less than 2 μm and a second non-volatile conditioning agent of particle size greater than 5 μm. The non-volatile conditioning agents may be silicones.

None of the above prior art documents disclose the use of intimate blends of combinations of silicones which result in individual particles comprising a mixture of silicones. In contrast, they describe addition of emulsions of each of the constituent silicone components separately to the hair compositions .

W098/43599 (Unilever) discloses a hair treatment composition, such as a shampoo or conditioner, comprising a silicone component comprising (i) 0.01 to 50% by weight of a silicone gum having a viscosity greater than 1 million cSt

2 -l (mm sec ) , (ii) 30 to 95% by weight of a silicone fluid

2 -1 having a viscosity of less that 100,000 cSt (mm sec ), and

(iii) 0.1 to 10% by weight of an amino functionalised silicone. The silicone component is preferably added as a single blend which may be in the form of a silicone mixture which is added to the composition during manufacture or alternatively it may be in the form of an aqueous emulsion which is added to the composition during manufacture.

This disclosure requires the presence of a high viscosity silicone gum in order to provide the lubricity required to give good conditioning. Such high viscosity gums present problems for processing and blending, because of their high viscosity.

We have surprisingly found that an intimate blend comprising a combination of a first silicone having a viscosity of less

2 -1 than 100,000 mm sec at 25 °C and a second silicone which is functionalised can be used in hair cleansing and treatment compositions to provide excellent conditioning benefits. In contrast to the teaching of W098/43599, it is not necessary to have a third, high viscosity silicone gum component in order to achieve the benefit of improved conditioning. Instead, a conditioning benefit is surprisingly obtained by combining two components which each provide low lubricity when used in isolation from each other.

Moreover, it has also been found that by use of droplets of the silicone blend which are greater than 5 micrometres in average diameter, excellent deposition and conditioning characteristics can be obtained from cleansing compositions without the need to include cationic deposition polymers. Such cationic deposition polymers are expensive components and can lead to a heavy, dirty feel to the hair on dry hair several hours after washing and drying for some consumers, so their removal from cleansing, conditioning compositions, without loss of conditioning benefits, is desirable.

SUMMARY OF THE INVENTION

In a first aspect, this invention provides a hair treatment composition comprising from 1 to 50% by weight of a cleansing surfactant and droplets of a silicone blend with a mean droplet diameter D_3r2 of greater than 5 micrometres, the silicone blend comprising

(i) from 50 to 96% by weight of the silicone content of the blend of a first silicone having a viscosity of

2 -1 less than 100,000 mm sec at 25 °C, and (ii) from 4 to 50% by weight of the silicone content of the blend of a second silicone which is functionalised.

DETAILED DESCRIPTION OF THE INVENTION

By water-insoluble it is meant that a component is less than 0.1% soluble by weight in water at 25 °C.

As used hereinafter, the term "first silicone" refers to component (i) of the silicone blend, i.e. the silicone

2 -1 having a viscosity of less than 100,000 mm sec at 25°C, and the term "second silicone" refers to component (ii) of the silicone blend, i.e. the silicone which is functionalised.

Silicone Component

The silicone content of the compositions of the invention provided by the silicone content of the silicone blend is suitably in the region of from 0.1 to 20%, preferably from 1 to 10% by weight of the composition.

Other silicones may optionally be added as separate components which are not incorporated into the silicone blend of the compositions .

The first silicone is present in an amount of at least 50% by weight based on the total silicone content of the silicone blend in the hair treatment composition and the second silicone is present in an amount of at least 11% by weight based on the total silicone content of the silicone blend in the hair treatment composition. It is preferred if the first silicone is water-insoluble. It is also preferred if the second silicone is water- insoluble. It is also preferred if both silicones are nonvolatile, i.e. they have a vapour pressure of 0.01 atmospheres or less at 25 °C.

The silicone component of the compositions according to the invention is provided as a single blend which is added to the composition during manufacture. This single blend may simply be in the form of a silicone mixture, which can be added to the composition during manufacture.

However, it is preferred that the single blend is in the form of an aqueous emulsion which is added to the composition during manufacture. Pre-formed aqueous emulsions of silicone may have advantages in that they themselves may be easier to handle or process than the "raw" silicone ingredients of the silicone component.

In any event, when added to the hair treatment composition, the silicone component becomes the internal phase of an emulsion which itself constitutes the hair treatment composition, and which is preferably water based.

A further feature of the invention is that the silicone present in the composition, when added as an already homogenised mixture, will be present in the hair treatment composition as a homogeneous mixture of silicones. That is, each silicone droplet in the composition will have essentially the same composition and will comprise a mixture of the two types of silicone which together make up the silicone component of the composition, i.e. first silicone and second silicone. Typically the mixture of the two types of silicones will be a single phase solution, but alternatively, it may be an intimate blend of two phases.

First Silicone

The first silicone is present at a level of at least 50% by weight, preferably at least 60%, more preferably at least 70% based on the total weight of the silicone content in the silicone blend in the composition.

The first silicone has a viscosity of less than 100,000

2 -1 2 -1 mm sec at 25 °C preferably less than 90,000 mm sec at

2 -1 25 °C, more preferably less than 70,000 mm sec at 25 °C.

Suitably, the first silicone has a molecular weight of less than 100,000 Dalton.

Suitable as the first silicone are polydiorganosiloxanes, preferably derived from suitable combinations of R3SiOo.₅ and

R2SiO units, where each R independently represents an alkyl, alkenyl (e.g. vinyl), alkaryl, aralkyl or afyl (e.g. phenyl) group. R is most preferably methyl. Thus, preferred first silicones for use in the silicone component of compositions of the invention are polydimethylsiloxanes (which have the CTFA designation dimethicone) , optionally having end groups such as hydroxyl . Good results have been obtained with dimethicone . Suitable materials include the DC200 series of silicone fluids, available from Dow Corning (e.g. DC200 with a

2 -1 viscosity of 60,000 mm sec at 25°C) . Members of the

Viscasil series of silicones, available from General Electric Silicones, are also suitable.

The first silicone is not functionalised other than optionally by end groups such as hydroxyl.

Second Silicone

The second silicone is present at a level of at least 4% by weight, preferably at least 11%, more preferably at least 14% and most preferably 19% by weight based on the total weight of the silicone component in the silicone blend of the composition.

Suitably, the second silicone has a viscosity of less than

2 -1 2

100,000 mm sec at 25°C, preferably less than 50,000 mm sec

1 2 -1 ' at 25 °C, more preferably less than 10,000 mm sec at 25 °C.

It is even more preferred if the viscosity of the second

2 -l silicone is less than 4,000 mm sec at 25°C, most preferably less than 2, 000.

Suitably, the second silicone has a molecular weight less than 100,000 Dalton, preferably less than 50,000 Dalton.

The second component of the silicone blend is a functionalised silicone. Suitable functionalised silicones include, for example, amino-, carboxy- , betaine-, quaternary ammonium-, carbohydrate-, hydroxy- and alkoxy-substituted silicones .

Preferably, the functionalised silicone contains multiple substitutions.

For the avoidance of doubt, as regards hydroxyl-substituted silicones, a polydimethylsiloxane merely having hydroxyl end groups (which have the CTFA designation dimethiconol) is not considered a functionalised silicone within the present invention. However, a polydimethylsiloxane having hydroxyl substitutions along the polymer chain is considered a functionalised silicone.

Preferred functionalised silicones are amino-functionalised silicones. Suitable amino functionalised silicones are described in EP 455,185 (Helene Curtis) and include trimethylsilylamodimethicone as depicted below, and are sufficiently water insoluble so as to be useful in compositions of the invention:

Si(CH₃)₃ - 0 - [Si(CH₃)₂ - 0 - ]_x - [Si (CH₃) (R - NH - CH₂CH₂ NH₂) - O -]_y - Si (CH₃)₃

wherein x + y is a number from about 50 to about 500, and the weight percent amine functionality is from 0.03% to 8%, and wherein R is an alkylene group having from 2 to 5 carbon atoms. Preferably, the number x + y is from 100 to 300, and the weight percent amine functionality is from 0.03% to 8%. As expressed here, the weight percent amine functionality is measured by titrating a sample of the amino-functionalised silicone against alcoholic hydrochloric acid to the bromocresol green end point. The weight percent amine is calculated using a molecular weight of 45 (corresponding to

CH₃- CH₂-NH₂) .

Suitably, the weight percent amine functionality measured and calculated in this way is from 0.03% to 8%, preferably from 0.5% to 4%.

An example of a commercially available amino-functionalised silicone useful in the silicone component of the composition of the invention is DC-8220 available from Dow Corning, which has a viscosity of 150 mm 2s-1 at 25 °C and a weight percent amine functionality of 2.0%.

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 DC-8220, DC-8166, DC-8466, and DC-8950-114 (all ex Dow Corning), and GE 1149-75, (ex

General Electric Silicones) . Suitable quaternary silicone polymers are described in EP-A-0 530 974. A preferred quaternary silicone polymer is K3474, ex Goldschmidt . The viscosity of silicones can be measured at 25 °C by means of a glass capillary viscometer as set out further in Dow Corning Corporate Test Method CTM004, July 20 1970.

Silicone Gum

Silicone gums are typically employed in shampoo and shower gel compositions in order to provide conditioning benefits.

These are polyorganodisiloxanes, typically with a viscosity

2 -l of greater than 1 million mm sec at 25 °C. Such gums are not needed in compositions according to the invention. Because of the processing difficulties inherent in using such gums it is preferred if silicone gums with a viscosity

2 -1 greater than 1 million mm sec are present at levels less than 0.1% by weight of the silicone component in the silicone blend, more preferably less than 0.01%, most preferably less than 0.001%.

Silicone Blend

One method for preparing compositions according to the invention is to first prepare liquid blend comprising a

2 -l first silicone with a viscosity of less than 100,000mm sec at 25 °C and a second functionalised silicone. This blend can then be added along with the other components comprising the hair treatment composition, followed by suitable mixing of the composition in order to ensure that the blend is dispersed as droplets of a suitable size. However it is preferred if the silicone blend is first formed into an aqueous emulsion prior to incorporation into the hair treatment composition. Thus another aspect of the invention is a method for incorporating droplets of silicone blend, the silicone blend comprising a first

2 -1 silicone with a viscosity of less than 100,000 mm sec at

25 °C and a second functionalised silicone, into a hair treatment composition, comprising the steps of; i) forming an intimate, non-aqueous blend comprising the first silicone and the second silicone, ii) preparing an aqueous emulsion comprising droplets comprising both the first silicone and the second silicone in the same droplets and iii) mixing said aqueous emulsion with the hair treatment composition; such that the mean droplet diameter is greater than 5 micrometres in the hair treatment composition.

For the silicone blend, it is preferred if the viscosity of the intimate blend of the first and second silicone is 1000

2 -1 -. , _ 2 -1 mm sec or more at 25 ° C, more preferably 2000 mm sec or

2 -l more, most preferably 5000 mm sec or more.

Suitable emulsifiers for use in the preparation of the aqueous emulsion are well known in the art and include anionic, cationic, zwitterionic, amphoteric and nonionic surfactants, and mixtures thereof. Examples of anionic surfactants used as emulsifiers for the silicone particles are alkylarylsulphonates, e.g., sodium dodecylbenzene sulphonate, alkyl sulphates e.g., sodium lauryl sulphate, alkyl ether sulphates, e.g., sodium lauryl ether sulphate nEO, where n is from 1 to 20, alkylphenol ether sulphates, e.g., octylphenol ether sulphate nEO where n is from 1 to 20, and sulphosuccinates, e.g., sodium dioctylsulphosuccinate.

Examples of nonionic surfactants used as emulsifiers for the silicone particles are alkylphenol ethoxylates, e.g., nonylphenol ethoxylate nEO, where n is from 1 to 50 and alcohol ethoxylates, e.g., lauryl alcohol nEO, where n is from 1 to 50, ester ethoxylates, e.g., polyoxyethylene monostearate where the number of oxyethylene units is from 1 to 30.

It is preferred if the emulsifier is blended into the silicone blend prior to the formation of the aqueous emulsion of the mixture droplets.

A preferred process for preparing oil-in-water emulsions of the mixed silicone droplets which can then be incorporated in the hair treatment compositions involves use of a mixer.

Depending upon the viscosities of components of the silicone mixture a suitable mixer should be chosen so as to provide sufficient shear to give the required final particle size of the emulsion. Examples of suitable benchtop mixers spanning the range of necessary shear are Heidolph RZR2100, Silverson L4R, Ystral X10/20-750 and Rannie Mini-Lab 7.30VH high pressure homogeniser. Other mixers of similar specification are well known to those skilled in the art and can also be used in this application. Equally it is possible to manufacture oil-in-water emulsions of this description on larger scale mixers which offer similar shear regimes to those described above .

The required amounts of the first and second silicones are combined under shear to produce a uniform mixture. To this mixture a suitable emulsifier system is added slowly with further shear. Examples of suitable emulsifier systems for this application are given above. As is well known to those skilled in the art, the emulsifier system can be used to help to control the final particle size of the emulsion.

When the addition of the emulsifier system is complete the aqueous portion of the emulsion is added slowly with the required level of shear so as to produce an emulsion with the desired particle size.

It is preferred if the aqueous phase of the emulsion contains a polymeric thickening agent to prevent phase separation of the emulsion after preparation. Preferred thickening agents are cross-linked polyacrylates, cellulosic polymers or derivatives of cellulosic polymers.

Alternatively the order of addition of these materials may sometimes be varied in order to achieve the same outcome.

Preferably, the mixer is also capable of having the temperature of mixing controlled, e.g. it comprises a jacket through which a heat transfer fluid can be circulated.

Preferably, the D₃,₂ average particle size of the silicone droplets in the emulsion and also in the final composition is greater than 5 micrometres, more preferably greater than 8 micrometres, and yet more preferably greater than 12 micrometres. Preferably, the average particle size of the silicone droplets in the emulsion and also in the final composition is 20 micrometres or less to prevent problems in stabilising the composition from separation of components.

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

Hair treatment compositions according to the invention may suitably take the form of shampoos or mousses.

Cationic Deposition Polymer

A cationic deposition polymer is often used in hair treatment compositions, for enhancing conditioning performance. However this leads to problems arising from the cationic polymer also remaining adhered to the hair, which can, in some cases, lead to a dirty, sticky feel to the hair some hours after use of the cleansing and conditioning composition for some consumers.

Such cationic polymers may be a homopolymer or be formed from two or more types of monomers . The molecular weight of the polymer will generally be between 5 000 and 10 000 000 Dalton, typically at least 10 000 and preferably from 100 000 to 2 000 000. The polymers will have cationic nitrogen containing groups such as quaternary ammonium or protonated amino groups, or a mixture thereof . It is highly preferred that compositions according to the invention should contain less than 0.04% by weight of such a cationic conditioning polymer, more preferably less than 0.02%, even more preferably less than 0.01%. It is most preferred that such polymers are absent from the composition.

Cleansing Surfactant

Compositions according to the invention will comprise one or more cleansing surfactants which are cosmetically acceptable and suitable for topical application to the hair. Further surfactants may be present as an additional ingredient if sufficient for cleansing purposes is not provided by the emulsifier for the water-insoluble oily component. It is preferred that shampoo compositions of the invention comprise at least one further surfactant (in addition to any used as emulsifying agent for the silicone component) to provide a cleansing benefit.

Suitable cleansing surfactants, which may be used singularly or in combination, are selected from anionic, amphoteric and zwitterionic surfactants, and mixtures thereof. The cleansing surfactant may be the same surfactant as the emulsifier, or may be different.

The total amount of surfactant (including any co-surfactant , and/or any emulsifier) in compositions of the invention is generally from 1 to 50, preferably from 2 to 40, more preferably from 10 to 25 percent by weight of the composition. Anionic Cleansing Surfactant

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

Examples of suitable anionic cleansing surfactants are the alkyl sulphates, alkyl ether sulphates, alkaryl sulphonates, alkanoyl isethionates, alkyl succinates, alkyl sulphosuccinates, N-alkyl sarcosinates, alkyl phosphates, alkyl ether phosphates, alkyl ether carboxylates, and alpha- olefin sulphonates, especially their sodium, magnesium, ammonium and mono-, di- and triethanolamine salts. The alkyl and acyl groups generally contain from 8 to 18 carbon atoms and may be unsaturated. The alkyl ether sulphates, alkyl ether phosphates and alkyl ether carboxylates may contain from 1 to 10 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, ammonium lauryl sulphate, sodium dodecylbenzene sulphonate, triethanolamine dodecylbenzene sulphonate, sodium cocoyl isethionate, sodium lauryl isethionate and sodium N-lauryl sarcosinate. The most preferred anionic surfactants are sodium lauryl sulphate, sodium lauryl ether sulphate (n) EO, (where n is from 1 to 3), ammonium lauryl sulphate and ammonium lauryl ether sulphate (n)E0, (where n is from 1 to 3) . Mixtures of any of the foregoing anionic cleansing surfactants may also be suitable.

The total amount of anionic cleansing surfactant in shampoo compositions of the invention is generally from generally from 0.5 to 45, preferably from 1.5 to 35, more preferably from 5 to 20 percent by weight of the composition.

Co-surfactant

The composition can include co-surfactants, to help impart aesthetic, physical or cleansing properties to the composition.

A preferred example is an a photeric or zwitterionic surfactant, which can be included in an amount ranging from 0 to about 8, preferably from 1 to 4 percent by weight.

Examples of amphoteric and zwitterionic surfactants include alkyl amine oxides, alkyl betaines, alkyl amidopropyl betaines, alkyl sulphobetaines (sultaines) , alkyl glycinates, alkyl carboxyglycinates, 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 and preferably lauryl betaine, cocamidopropyl betaine and sodium cocamphopropionate . Another preferred example is a nonionic surfactant, which can be included in an amount ranging from 0 to 8, preferably from 2 to 5 percent by weight of the composition.

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.

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 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 C₂o- Preferably R represents a mean alkyl chain length of from about Cg to about C_3.2 • Most preferably the value of R lies between about 9.5 and about 10.5. G may be selected from C₅ or Q monosaccharide residues, and is preferably a glucoside. G may be selected from the group comprising glucose, xylose, lactose, fructose, mannose and derivatives thereof. Preferably G is glucose.

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

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 .

Other sugar-derived nonionic surfactants which can be included in compositions of the invention include the Cio-Ciβ N-alkyl (Ci-Cg) polyhydroxy fatty acid amides, such as the

C₁₂-C₁₈ N-methyl glucamides, as described for example in WO 92 06154 and US 5 194 639, and the N-alkoxy polyhydroxy fatty acid amides, such as Cio-Cis N- (3-methoxypropyl) glucamide .

The composition according to the invention can also optionally include one or more cationic co-surfactants included in an amount ranging from 0.01 to 10, more preferably from 0.05 to 5, most preferably from 0.05 to 2 percent by weight of the composition. A preferred blend of surfactants comprises a mixture of ammonium lauryl ether sulfate, ammonium lauryl sulfates , PEG 5 cocamide and cocomide MEA (CTFA designations) .

Suspending Agents

Optionally, the compositions according to the invention further comprise from 0.1 to 10 percent by weight, preferably from 0.6% to 6%, of 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.

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 940, Carbopol 941 and Carbopol 980. An example of a suitable copolymer of a carboxylic acid containing a monomer and acrylic acid esters is Carbopol 1342. All Carbopol (trade mark) 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.

Adjuvants

The compositions of the present invention may also contain adjuvants suitable for hair care. Generally such ingredients are included individually at a level of up to 2, preferably up to 1 % by weight of the total composition.

Among suitable hair care adjuvants, are natural hair root nutrients, such as amino acids and sugars. Examples of suitable amino acids include arginine, cysteine, glutamine, glutamic acid, isoleucine, leucine, methionine, serine and valine, and/or precursors and derivatives thereof. The amino acids may be added singly, in mixtures, or in the form of peptides, e.g. di- and tripeptides. The amino acids may also be added in the form of a protein hydrolysate, such as a keratin or collagen hydrolysate. Suitable sugars are glucose, dextrose and fructose. These may be added singly or in the form of, e.g. fruit extracts. A particularly preferred combination of natural hair root nutrients for inclusion in compositions of the invention is isoleucine and glucose. A particularly preferred amino acid nutrient is arginine. Another suitable adjuvant is glycolic acid. Optional Ingredients

Compositions of this invention may contain any other ingredient normally used in hair treatment formulations. These other ingredients may include viscosity modifiers, preservatives, colouring agents, polyols such as glycerine and polypropylene glycol, chelating agents such as EDTA, antioxidants, fragrances, antimicrobials and sunscreens. 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.

Mousses

Hair treatment cleansing and conditioning compositions in accordance with the invention may also take the form of aerosol foams (mousses) in which case a propellant is included in the composition. This agent is responsible for expelling the other materials from the container and forming the hair mousse character.

The propellant gas can be any liquefiable gas conventionally used for aerosol containers. Examples of suitable propellants include dimethyl ether, propane, n-butane and isobutane, used singly or in admixture.

The amount of the propellant gases is governed by normal factors well known in the aerosol art. For hair mousses, the level of propellant is generally from 3 to 30, preferably from 5 to 15 % by weight of the total composition.

Mode of Use

The compositions of the invention are primarily intended for topical application to the hair and/or scalp and or skin of a human subject as rinse-off treatments to clean the hair or body while improving hair fibre surface properties such as smoothness, softness, manageability, cuticle integrity, and shine. Typically such compositions are known in the art as shampoos, cleansing mousses or shower gels.

Claims

1. A hair treatment composition comprising from 1 to 50% by weight of a cleansing surfactant and droplets of a silicone blend with a mean droplet diameter D₃,₂ of greater than 5 micrometres, the silicone blend comprising:

(i) from 50 to 96% by weight of the silicone content of the blend of a first silicone having a

2 -1 viscosity of less than 100,000 mm sec at 25°C, and

(ii) from 4 to 50% by weight of the silicone content of the blend of a second silicone which is functionalised.

2. A composition according to claim 1 wherein the silicone blend comprises less than 0.01% by weight of a silicone gum based on the total weight of silicone content of the blend.

3. A composition according to any preceding claim wherein the mean droplet diameter (0₃,₂) of the droplets of silicone blend is greater than 8 micrometres.

4. A composition according to any preceding claim comprising less than 0.01% by weight of a cationic deposition polymer.

5. A composition according to any preceding claim, in which the silicone content in the hair treatment composition contained in the silicone blend is from 0.1 to 20% by weight based on the total weight of the composition.

6. A composition according to any preceding claim, in which the first silicone is a polydimethylsiloxane.

7. A composition according to any preceding claim, in which the second silicone is an amino-functionalised silicone.

8. A composition according to claim 7, in which the amino- functionalised silicone has a weight percent amino functionality from 0.03% to 8%.

9. A method for incorporating droplets of silicone blend, the silicone blend comprising a first silicone with a

2 -l viscosity of less than 100,000 mm sec at 25 °C and a second functionalised silicone, into a hair treatment composition, comprising the steps of; i) forming an intimate, non-aqueous blend comprising the first silicone and the second silicone, ii) preparing an aqueous emulsion comprising droplets comprising both the first silicone and the second silicone in the same droplets and iii) mixing said aqueous emulsion with the hair treatment composition; such that the mean droplet diameter is greater than 5 micrometres in the hair treatment composition.