Patent Description:
The present invention also relates to a process for the cosmetic treatment of keratin materials, in particular keratin fibres, preferably human keratin fibres such as the hair, in which the composition is applied to said materials.

Finally, the invention relates to the use of the composition for the cosmetic treatment of keratin materials, in particular keratin fibres, preferably human keratin fibres such as the hair.

Compositions in the form of nanoemulsions, in particular the oil-in-water type (O/W), are well known in the cosmetics and dermatology domain, in particular for preparing cosmetic products such as lotions, creams, tonics, serums or eau de toilette to be applied to the skin and/or hair.

Compositions in nanoemulsion form generally have a number-average oil drop (or oily globule) size less than <NUM> nanometres, said oil drops being stabilized by a layer of amphiphilic molecules that can optionally form a liquid crystal phase of the lamellar type, located at the oil/aqueous phase interface.

The term "amphiphilic molecule" is intended to mean herein any molecule having a bipolar structure, i.e. including at least one hydrophobic part and at least one hydrophilic part and having the property of reducing the surface tension of water (γ < 55mN/m) and of reducing the interface tension between water and an oily phase. Amphiphilic molecules are for example surfactants, surface agents or emulsifiers.

Due to the small oil drop size, compositions in the form of a nanoemulsion offer a certain number of advantages from a cosmetic or dermatological point of view leading in particular to a uniform and effective deposit of the composition on the skin and/or hair; in particular for the hair, a uniform deposit from the root to the end, while allowing satisfactory oil penetration and persistence.

Furthermore, compositions in nanoemulsion form confer improved cosmetic properties on keratin materials. In particular, for keratin fibres such as the hair, compositions in nanoemulsion form confer good disentangling, softness, feel, rinsability and suppleness properties and have a very good conditioning effect, which usually prove to be better than those obtained with the conventional emulsions and dispersions used in the cosmetics field.

<CIT> discloses a cosmetic composition in the form of an oil-in-water nanoemulsion comprising one or more nonionic amphiphilic lipids, one or more volatile linear alkanes and one or more oils different from said volatile linear alkane(s).

Nevertheless, these compositions remain relatively liquid which can present disadvantages, for example in terms of usage qualities. More specifically, such compositions do not make it possible to guarantee sufficiently precise application to the fibres without the risk of running, in particular when they are sprayed.

In addition, there is still a need to obtain new innovative textures, in particular for compositions in nanoemulsion form, while at the same time retaining the advantages offered by this type of composition.

It has now been discovered, surprisingly, that a composition in the form of a nanoemulsion comprising (i) at least <NUM>% by weight, relative to the total weight of the composition, of one or more fatty substances including at least one plant oil, (ii) one or more cationic surfactants, and (iii) water make it possible to meet the needs expressed above.

In particular, such a composition has an original gellified texture which does not require the addition of thickening polymers or a gelling agent.

A subject of the invention is thus a cosmetic composition in the form of an oil-in-water nanoemulsion comprising:.

The composition according to the invention thus has a gelled texture ensuring a certain number of advantages.

First of all, the composition according to the invention has an attractive visual for the consumer.

In addition, it has a creamy texture which in particular makes it possible in particular to achieve a better localization of the composition on the keratin materials, in particular the keratin fibres such as the hair, during its application while at the same time minimizing the risks of running and/or splashing, in particular into the eyes.

In addition, the composition according to the invention enables a gentle and uniform coating of the keratin fibres from the root to the end.

The depositing of active products on the keratin fibres (fatty substances, vitamins) also proves to be greater than for a conventional care product.

In other words, the composition has improved usage qualities guaranteeing both a distribution without running that is more targeted at the point of application, and uniform spreading on the keratin fibres.

Moreover, the composition according to the invention is stable with respect to storage over time, both at ambient temperature (<NUM>) and at higher temperatures, in particular <NUM>.

For the purposes of the present invention, the term "stable with respect to storage over time" is intended to mean that the following physical characteristics of the composition vary little, or even not at all, over time: appearance, pH, rheology (viscosity, consistency).

In particular, the composition does not give rise to any phase-separation or exudation phenomena over time, and at the intended storage temperature.

The composition above also confers improved cosmetic properties on the keratin materials treated with these compositions. In particular for keratin fibres, preferably the hair, the composition according to the invention confers good rinsability properties, and good conditioning properties, in particular in terms of disentangling, softness, feel and suppleness.

More specifically, the composition according to the invention, on contact with the keratin materials, is converted into a bluish-coloured milk, which makes it very easy and quick to rinse off.

Finally, the composition above has the advantage of being able to be prepared by any type of preparation process, and in particular using a process which is low in energy and easily industrializable.

The invention also relates to a process for the cosmetic treatment of keratin materials, in particular human keratin fibres such as the hair, in which the composition according to the invention is applied to said materials.

Finally, the invention relates to the use of said composition for the cosmetic treatment of keratin materials, in particular human keratin fibres such as the hair.

Likewise, the composition according to the invention can also be used for caring for the skin.

Other subjects, characteristics, aspects and advantages of the invention will emerge even more clearly on reading the description and the examples that follow.

In the following text, and unless otherwise indicated, the limits of a range of values are included in that range, especially in the expressions "between" and "ranging from.

Moreover, the expression "at least one" used in the present description is equivalent to the expression "one or more".

The cosmetic composition according to the invention is preferably a cosmetic composition for treating keratin fibres, in particular human keratin fibres such as the hair.

The composition according to the invention comprises at least <NUM>% by weight, relative to the total weight of the composition, of one or more fatty substances, including at least one plant oil.

The term "fatty substance" is intended to mean an organic compound that is insoluble in water at ambient temperature (<NUM>) and at atmospheric pressure (<NUM>×<NUM><NUM> Pa), i.e. which has a solubility of less than <NUM>% by weight, preferably less than <NUM>% by weight. They are generally soluble, under the same temperature and pressure conditions, in organic solvents such as chloroform, ethanol, benzene, liquid petroleum jelly or decamethylcyclopentasiloxane.

Preferably, the fatty substance(s) are chosen from fatty substances that are liquid at <NUM> and at atmospheric pressure (<NUM>×<NUM><NUM> Pa).

Preferably, the fatty substance(s) of the composition according to the invention are non-silicone.

The term "non-silicone fatty substance" is intended to mean a fatty substance of which the structure does not comprise any silicon atoms, and which therefore especially does not comprise any siloxane groups. They generally bear in their structure a hydrocarbon-based chain comprising at least <NUM> carbon atoms. Advantageously, they are not oxyalkylenated and do not contain any -COOH functions.

The fatty substances that can be used in the invention preferably have a viscosity of less than or equal to <NUM> Pa. s, better still less than or equal to <NUM> Pa. s and even better still less than or equal to <NUM> Pa. s at a temperature of <NUM> and at a shear rate of <NUM>-<NUM> measured with a Rheomat RM1800 (generally with spindle <NUM> or <NUM>).

The fatty substances that can be used in the composition according to the invention may be chosen especially from liquid hydrocarbons, liquid fatty alcohols, liquid fatty esters including plant oils, and liquid fatty acids, and mixtures of these compounds.

For the purposes of the present invention, the term "liquid hydrocarbon" is intended to mean a hydrocarbon composed solely of carbon and hydrogen atoms, which is liquid at a temperature of <NUM> and at atmospheric pressure (<NUM> mmHg, i.e. <NUM>×<NUM><NUM> Pa).

More particularly, the liquid hydrocarbons are chosen from:.

Preferably, the liquid hydrocarbon(s) are chosen from liquid paraffins, isoparaffins, liquid petroleum jelly, undecane, tridecane and isododecane, and mixtures thereof.

In a most particularly preferred variant, the liquid hydrocarbon(s) are chosen from liquid petroleum jelly, isoparaffins, isododecane and a mixture of undecane and tridecane.

For the purposes of the present invention, the term "liquid fatty alcohol" is intended to mean a non-glycerolated and non-oxyalkylenated fatty alcohol, which is liquid at a temperature of <NUM> and at atmospheric pressure (<NUM> mmHg, i.e. <NUM>×<NUM><NUM> Pa). Preferably, the liquid fatty alcohols of the invention comprise from <NUM> to <NUM> carbon atoms, especially from <NUM> to <NUM> carbon atoms, and may be saturated or unsaturated.

The saturated liquid fatty alcohols are preferably branched. They may optionally comprise in their structure at least one aromatic or non-aromatic ring, which is preferably acyclic.

More particularly, the saturated liquid fatty alcohols of the invention are chosen from octyldodecanol, <NUM>-decyltetradecanol, isostearyl alcohol and <NUM>-hexyldecanol.

Octyldodecanol and <NUM>-decyltetradecanol are most particularly preferred.

The unsaturated liquid fatty alcohols contain in their structure at least one double or triple bond, and preferably one or more double bonds. When several double bonds are present, there are preferably <NUM> or <NUM> of them, and they may be conjugated or unconjugated.

These unsaturated fatty alcohols may be linear or branched.

They may optionally comprise in their structure at least one aromatic or non-aromatic ring. They are preferably acyclic.

More particularly, the unsaturated liquid fatty alcohols that may be used in the invention are chosen from oleyl alcohol, linoleyl alcohol, linolenyl alcohol and undecylenyl alcohol.

Oleyl alcohol is most particularly preferred.

For the purposes of the present invention, the term "liquid fatty ester" is intended to mean an ester derived from a fatty acid and/or from a fatty alcohol, which is liquid at a temperature of <NUM> and at atmospheric pressure (<NUM> mmHg, i.e. <NUM>×<NUM><NUM> Pa).

More particularly, the liquid esters are chosen from esters of saturated or unsaturated, linear or branched C<NUM>-C<NUM> aliphatic mono- or polyacids, which are optionally hydroxylated, and from saturated or unsaturated, linear or branched C<NUM>-C<NUM> aliphatic mono- or polyalcohols, the total number of carbon atoms in the esters being greater than or equal to <NUM>.

Preferably, for the esters of monoalcohols, at least one from among the alcohol and the acid from which the esters of the invention are derived is branched.

Among the monoesters of monoacids and of monoalcohols, mention may be made of alkyl palmitates, in particular of C<NUM>-C<NUM>, especially ethyl palmitate and isopropyl palmitate, alkyl myristates in particular of C<NUM>-C<NUM>, such as isopropyl myristate or ethyl myristate, alkyl stearates, in particular of C<NUM>-C<NUM>, especially isocetyl stearate, <NUM>-ethylhexyl isononanoate, isodecyl neopentanoate and isostearyl neopentanoate.

Esters of optionally hydroxylated C<NUM>-C<NUM> dicarboxylic or tricarboxylic acids and of C<NUM>-C<NUM> alcohols and esters of optionally hydroxylated monocarboxylic, dicarboxylic or tricarboxylic acids and of C<NUM>-C<NUM> dihydroxy, trihydroxy, tetrahydroxy or pentahydroxy non-sugar alcohols may also be used.

Mention may be made especially of diethyl sebacate, diisopropyl sebacate, diisopropyl adipate, di-n-propyl adipate, dioctyl adipate, diisostearyl adipate, dioctyl maleate, glyceryl undecylenate, octyldodecyl stearoyl stearate, pentaerythrityl monoricinoleate, pentaerythrityl tetraisononanoate, pentaerythrityl tetrapelargonate, pentaerythrityl tetraisostearate, pentaerythrityl tetraoctanoate, propylene glycol dicaprylate, propylene glycol dicaprate, tridecyl erucate, triisopropyl citrate, triisostearyl citrate, glyceryl trilactate, glyceryl trioctanoate, trioctyldodecyl citrate, trioleyl citrate, propylene glycol dioctanoate, neopentyl glycol diheptanoate, diethylene glycol diisononanoate, polyethylene glycol distearates, and alkyl malates, especially (C<NUM>-C<NUM>)alkyl malates, in particular bis(C<NUM>-C<NUM>)alkyl malate. Among the esters mentioned above, use is preferentially made of ethyl, isopropyl, myristyl, cetyl or stearyl palmitate, <NUM>-ethylhexyl palmitate, <NUM>-octyldecyl palmitate, alkyl myristates such as isopropyl, butyl, cetyl or <NUM>-octyldodecyl myristate, hexyl stearate, propylene glycol dicaprylate, butyl stearate, isobutyl stearate; dioctyl malate, hexyl laurate, <NUM>-hexyldecyl laurate, isononyl isononanoate, cetyl octanoate and bis(C<NUM>-C<NUM>)alkyl malate. Among the liquid fatty esters, use may be made of sugar esters and diesters of C<NUM>-C<NUM> and preferably C<NUM>-C<NUM> fatty acids.

The term "sugar" is intended to mean oxygen-bearing hydrocarbon-based compounds containing several alcohol functions, with or without aldehyde or ketone functions, and which comprise at least <NUM> carbon atoms. These sugars may be monosaccharides, oligosaccharides or polysaccharides.

Preferably, these said sugars are chosen from sucrose, glucose, galactose, ribose, fucose, maltose, fructose, mannose, arabinose, xylose and lactose, and derivatives thereof, especially alkyl derivatives, such as methyl derivatives, for instance methylglucose.

The sugar and fatty acid esters may be chosen especially from the group comprising the esters or mixtures of esters of sugars described previously and of linear or branched, saturated or unsaturated C<NUM>-C<NUM> and preferably C<NUM>-C<NUM> fatty acids.

If they are unsaturated, these compounds may comprise one to three conjugated or unconjugated carbon-carbon double bonds.

The esters according to this variant may also be chosen from mono-, di-, tri- and tetraesters, and polyesters, and mixtures thereof.

These esters may be, for example, oleates, laurates, palmitates, myristates, behenates, cocoates, stearates, linoleates, linolenates, caprates and arachidonates, and mixtures thereof, such as, especially, oleopalmitate, oleostearate or palmitostearate mixed esters.

More particularly, use is made of monoesters and diesters and especially of sucrose, glucose or methylglucose mono- or dioleates, stearates, behenates, oleopalmitates, linoleates, linolenates or oleostearates, or alternatively of methylglucose dioleate (Glucate® DO).

Among the sugar esters, use may be made of pentaerythrityl esters, preferably pentaerythrityl tetraisostearate, pentaerythrityl tetraoctanoate, and caprylic and capric acid hexaesters as a mixture with dipentaerythritol.

Among the natural or synthetic monoacid, diacid or triacid esters with glycerol, use may be made of plant oils or synthetic oils.

More particularly, said plant oil(s) or synthetic oil(s) are chosen from triglyceride oils of plant or synthetic origin, such as liquid fatty acid triglycerides containing from <NUM> to <NUM> carbon atoms, for instance heptanoic or octanoic acid triglycerides, or alternatively, for example, sesame oil, soybean oil, coffee oil, safflower oil, borage oil, sunflower oil, olive oil, apricot kernel oil, camellia oil, bambara pea oil, avocado oil, mango oil, rice bran oil, cottonseed oil, rose oil, kiwi seed oil, sea buckthorn pulp oil, blueberry seed oil, poppy seed oil, orange pip oil, sweet almond oil, palm oil, copra oil, vernonia oil, marjoram oil, baobab oil, rapeseed oil, ximenia oil, pracaxi oil, caprylic/capric acid triglycerides such as those sold by the company Stéarineries Dubois or those sold under the names Miglyol® <NUM>, <NUM> and <NUM> by the company Dynamit Nobel, jojoba oil and shea butter oil.

As liquid esters that may be used according to the invention, use is preferably made of triglycerides of plant origin, in particular oils chosen from avocado oil, olive oil, camellia oil and apricot kernel oil, sunflower oil, shea oil, jojoba oil, soybean oil, copra (or coconut) oil, rapeseed oil, and mixtures thereof, and C<NUM>-C<NUM> dicarboxylic or tricarboxylic acid esters of C<NUM>-C<NUM> alcohols, in particular <NUM>,<NUM>-propanediol dicaprylate.

The term "fatty acid" is intended to mean a non-salified fatty acid, i.e. the fatty acid must not be in the form of a generally soluble soap, i.e. it must not be salified with a base.

More particularly, the liquid fatty acids that may be used according to the invention are chosen from the acids of formula RCOOH, in which R is a saturated or unsaturated, linear or branched radical preferably comprising from <NUM> to <NUM> carbon atoms.

Preferably, R is a C<NUM>-C<NUM> alkyl or C<NUM>-C<NUM> alkenyl group and better still a C<NUM>-C<NUM> alkyl or C<NUM>-C<NUM> alkenyl group. R may be substituted with one or more hydroxyl groups and/or one or more carboxyl groups.

Preferentially, the liquid fatty acid(s) are chosen from oleic acid, linoleic acid and isostearic acid.

As indicated above, the composition according to the invention comprises at least one plant oil, preferably the plant oil(s) is(are) chosen from one or more triglyceride oils, and in particular chosen from sesame oil, soybean oil, coffee oil, safflower oil, borage oil, sunflower oil, olive oil, apricot kernel oil, camelia oil, bambara pea oil, avocado oil, mango oil, rice bran oil, cottonseed oil, rose oil, kiwi seed oil, sea buckthorn pulp oil, blueberry seed oil, poppy seed oil, orange pip oil, sweet almond oil, palm oil, copra oil, vernonia oil, marjoram oil, baobab oil, rapeseed oil, ximenia oil, pracaxi oil, jojoba oil, shea butter oil and mixtures thereof.

Preferentially, the composition according to the invention comprises one or more plant oils chosen from avocado oil, olive oil, camelia oil, apricot kernel oil, sunflower oil, shea oil, jojoba oil, soybean oil, copra (or coconut) oil, rapeseed oil and mixtures thereof.

The composition may also comprise one or more additional fatty substances other than plant oils, preferably chosen from liquid fatty substances other than plant oils, preferentially chosen from liquid hydrocarbons, liquid fatty esters other than plant oils and mixtures of these compounds.

Most particularly preferably, the composition according to the invention comprises one or more additional, preferably liquid, fatty substances chosen from linear or branched C<NUM>-C<NUM> alkanes, and in particular chosen from undecane, tridecane, and a mixture of these compounds.

Most particularly preferably, the composition according to the invention comprises, as fatty substance:.

The composition according to the invention comprises one or more, preferably liquid, fatty substances, including at least one plant oil generally in a total content ranging from <NUM>% to <NUM>% by weight, preferably from <NUM>% to <NUM>% by weight and more preferentially from <NUM>% to <NUM>% by weight, better still from <NUM>% to <NUM>% by weight, relative to the total weight of the composition.

According to one preferred variant of the invention, the composition of the invention comprises at least <NUM>% by weight of one or more plant oils, preferably at least <NUM>% by weight, relative to the total weight of the composition.

In particular, the composition of the invention comprises the plant oil(s) in a total content ranging from <NUM>% to <NUM>% by weight, preferably from <NUM>% to <NUM>% by weight, more preferentially from <NUM>% to <NUM>% by weight, relative to the total weight of the composition.

The composition comprises one or more cationic surfactants chosen from those corresponding to general formula (I) as described below, quaternary ammonium salts of imidazoline, di- or tri-quaternary ammonium salts and quaternary ammonium salts containing at least one ester function.

The term "cationic surfactant" is intended to mean a surfactant that is positively charged when it is contained in the composition according to the invention. This surfactant may bear one or more positive permanent charges or may contain one or more cationizable functions in the composition according to the invention.

The cationic surfactants which may be used in the composition according to the invention are:.

Among the quaternary ammonium salts of formula (I), the ones that are preferred are, on the one hand, tetraalkylammonium salts, for instance dialkyldimethylammonium or alkyltrimethylammonium salts in which the alkyl group comprises approximately from <NUM> to <NUM> carbon atoms, in particular behenyltrimethylammonium, distearyldimethylammonium or cetyltrimethylammonium salts, or, on the other hand, the palmitylamidopropyltrimethylammonium salts, the stearamidopropyltrimethylammonium salts, the stearamidopropyldimethylcetearylammonium salts, or the stearamidopropyldimethyl(myristyl acetate)ammonium salts sold under the name Ceraphyl® <NUM> by the company Van Dyk. It is preferred in particular to use the chloride salts of these compounds.

The alkyl groups R<NUM> may be linear or branched, and more particularly linear.

Preferably, R<NUM> denotes a methyl, ethyl, hydroxyethyl or dihydroxypropyl group, and more particularly a methyl or ethyl group.

Advantageously, the sum x + y + z is from <NUM> to <NUM>.

When R<NUM> is a hydrocarbon-based group R<NUM>, it may be long and contain from <NUM> to <NUM> carbon atoms, or may be short and contain from <NUM> to <NUM> carbon atoms.

When R<NUM> is a hydrocarbon-based group R<NUM>, it preferably contains <NUM> to <NUM> carbon atoms.

Advantageously, R<NUM>, R<NUM> and R<NUM>, which may be identical or different, are chosen from linear or branched, saturated or unsaturated C<NUM>-C<NUM> hydrocarbon-based groups, and more particularly from linear or branched, saturated or unsaturated C<NUM>-C<NUM> alkyl and alkenyl groups.

Preferably, x and z, which may be identical or different, are equal to <NUM> or <NUM>.

Preferably, r, s and t, which may be identical or different, are equal to <NUM> or <NUM>, and even more particularly are equal to <NUM>.

The anion X- is preferably a halide (chloride, bromide or iodide) or an alkyl sulfate, more particularly methyl sulfate. However, use may be made of methanesulfonate, phosphate, nitrate, tosylate, an anion derived from an organic acid, such as acetate or lactate, or any other anion that is compatible with the ammonium bearing an ester function.

The anion X- is even more particularly chloride or methyl sulfate.

Use may be made more particularly in the composition according to the invention of the ammonium salts of formula (IV) in which:.

Advantageously, the hydrocarbon-based groups are linear.

Examples that may be mentioned include the compounds of formula (IV) such as the diacyloxyethyldimethylammonium, diacyloxyethylhydroxyethylmethylammonium, monoacyloxyethyl-dihydroxyethylmethylammonium, triacyloxyethylmethylammonium and monoacyloxyethylhydroxyethyldimethylammonium salts (chloride or methyl sulfate in particular), and mixtures thereof. The acyl groups preferably contain from <NUM> to <NUM> carbon atoms and are derived more particularly from a plant oil such as palm oil or sunflower oil. When the compound contains several acyl groups, these groups may be identical or different.

These products are obtained, for example, by direct esterification of triethanolamine, triisopropanolamine, an alkyldiethanolamine or an alkyldiisopropanolamine, which are optionally oxyalkylenated, with C<NUM>-C<NUM> fatty acids or with mixtures of C<NUM>-C<NUM> fatty acids of plant or animal origin, or by transesterification of the methyl esters thereof. This esterification is followed by a quaternization using an alkylating agent such as an alkyl halide (preferably a methyl or ethyl halide), a dialkyl sulfate (preferably a methyl or ethyl sulfate), methyl methanesulfonate, methyl para-toluenesulfonate, glycol chlorohydrin or glycerol chlorohydrin.

Such compounds are sold, for example, under the names Dehyquart® by the company Henkel, Stepanquat® by the company Stepan, Noxamium® by the company Ceca or Rewoquat® WE <NUM> by the company Rewo-Witco.

The composition according to the invention may contain, for example, a mixture of quaternary ammonium monoester, diester and triester salts with a weight majority of diester salts.

Use may also be made of the ammonium salts containing at least one ester function that are described in patents <CIT> and <CIT>.

Use may be made of behenoylhydroxypropyltrimethyl-ammonium chloride sold by KAO under the name Quatarmin BTC <NUM>.

Preferably, the ammonium salts containing at least one ester function contain two ester functions.

Among the quaternary ammonium salts containing at least one ester function, which may be used, it is preferred to use dipalmitoyl-ethylhydroxyethylmethylammonium salts.

The cationic surfactant(s) are preferably chosen from those of formula (I) and those of formula (IV) and even more preferentially from those of formula (I).

Most particularly preferably, the cationic surfactant(s) of the invention are chosen from those of formula (I), more preferentially from behenyltrimethylammonium salts, cetyltrimethylammonium salts, and a mixture of these compounds, and even more preferentially from behenyltrimethylammonium chloride, cetyltrimethylammonium chloride, and a mixture of these compounds.

The cationic surfactant(s) advantageously represent from <NUM>% to <NUM>% by weight, preferably from <NUM>% to <NUM>% by weight and more preferentially from <NUM>% to <NUM>% by weight, relative to the total weight of the composition.

Particularly preferably, the composition according to the invention does not comprise any gelling agent, thickening polymers, fatty alcohols that are solid and fatty acids that are solid at a temperature of <NUM> and at atmospheric pressure.

The composition according to the invention may also comprise one or more polyols.

For the purposes of the present invention, the term "polyol" is intended to mean an organic compound constituted of a hydrocarbon-based chain optionally interrupted with one or more oxygen atoms and bearing at least two free hydroxyl groups (-OH) borne by different carbon atoms, this compound possibly being cyclic or acyclic, linear or branched, and saturated or unsaturated.

More particularly, the polyol(s) that may be used according to the invention comprise from <NUM> to <NUM> hydroxyl groups, more preferentially from <NUM> to <NUM> hydroxyl groups and even more preferentially from <NUM> to <NUM> hydroxyl groups.

The polyol(s) that may be used according to the invention generally comprise at least three carbon atoms.

Preferably, said polyol(s) that may be used according to the invention are chosen from polyols comprising at least three carbon atoms and ethylene glycol, and are preferably chosen from <NUM>,<NUM>-propanediol, <NUM>,<NUM>-butylene glycol, <NUM>,<NUM>-pentanediol, dipropylene glycol, hexylene glycol, pentylene glycol, glycerol, ethylene glycol and sorbitol, and a mixture of these compounds.

Most particularly preferably, the polyol(s) that can be used according to the invention are chosen from glycerol, sorbitol or a mixture of these compounds, and preferably the polyol is glycerol.

Advantageously, the composition according to the invention does not comprise propylene glycol.

When they are present, the polyol(s) represent from <NUM>% to <NUM>% by weight, better still from <NUM>% to <NUM>% by weight and more preferentially from <NUM>% to <NUM>% by weight, relative to the total weight of the composition.

The composition according to the invention generally comprises water.

Water advantageously represents from <NUM>% to <NUM>% by weight, preferably from <NUM>% to <NUM>% by weight and more preferentially from <NUM>% to <NUM>% by weight relative to the total weight of the composition.

The composition according to the invention may also comprise one or more organic solvents other than polyols.

Preferably, the organic solvent(s) other than polyols are chosen from non-aromatic C<NUM>-C<NUM> alcohols such as ethyl alcohol or isopropyl alcohol, or aromatic alcohols such as benzyl alcohol and phenylethyl alcohol.

Particularly preferably, the composition according to the invention comprises one or more organic solvents other than polyols, the organic solvent preferably being ethanol.

When they are present in the composition according to the invention, the organic solvent(s) other than polyols generally represent from <NUM>% to <NUM>% by weight and preferably from <NUM>% to <NUM>% by weight relative to the total weight of the composition.

The pH of the composition of the invention is generally between <NUM> and <NUM>, preferably between <NUM> and <NUM>, better still between <NUM> and <NUM>.

The pH of the composition according to the invention may be adjusted to the desired value by means of acidifying or basifying agents usually used in cosmetic compositions, or alternatively using standard buffer systems.

Among the acidifying agents, examples that may be mentioned include mineral acids, for instance hydrochloric acid, (ortho)phosphoric acid, boric acid, nitric acid or sulfuric acid, or organic acids, for instance compounds comprising at least one carboxylic acid function such as acetic acid, tartaric acid, citric acid or lactic acid, a sulfonic acid function, a phosphonic acid function or a phosphoric acid function.

Preferably, phosphoric acid is used as acidifying agent.

The basifying agent(s) may be mineral, organic or hybrid.

The mineral alkaline agent(s) are preferably chosen from aqueous ammonia, alkali metal carbonates or bicarbonates such as sodium carbonate or bicarbonate, potassium carbonate or bicarbonate, sodium hydroxide or potassium hydroxide or mixtures thereof.

The organic alkaline agent(s) are preferably chosen from organic amines with a pKb at <NUM> of less than <NUM>, preferably of less than <NUM> and even more advantageously of less than <NUM>. It should be noted that it is the pKb corresponding to the function of highest basicity. In addition, the organic amines do not comprise any alkyl or alkenyl fatty chain comprising more than ten carbon atoms.

The organic alkaline agent(s) are chosen, for example, from alkanolamines, oxyethylenated and/or oxypropylenated ethylenediamines, amino acids and the compounds of formula (VIII) below:
<CHM>
in which W is a divalent C<NUM> to C<NUM> alkylene radical optionally substituted with one or more hydroxyl groups or a C<NUM> to C<NUM> alkyl radical, and/or optionally interrupted with one or more heteroatoms such as O, or NRu; Rx, Ry, Rz, Rt and Ru, which may be identical or different, represent a hydrogen atom or a C<NUM> to C<NUM> alkyl, C<NUM> to C<NUM> hydroxyalkyl or C<NUM> to C<NUM> aminoalkyl radical.

Examples of amines of formula (VIII) that may be mentioned include <NUM>,<NUM>-diaminopropane, <NUM>,<NUM>-diamino-<NUM>-propanol, spermine and spermidine.

The composition according to the invention may also comprise one or more additives.

As additives that may be used in accordance with the invention, mention may be made of antidandruff agents, anti-seborrhoea agents, agents for preventing hair loss and/or for promoting hair regrowth, vitamins and provitamins including panthenol, sunscreens, mineral or organic pigments, sequestrants, plasticizers, solubilizers, opacifiers or pearlescent agents, antioxidants, fragrances, preservatives and pigments.

Those skilled in the art will take care to select the optional additives and the amount thereof such that they do not harm the properties of the composition according to the invention.

These additives may be present in the composition according to the invention in an amount ranging from <NUM> to <NUM>% by weight, relative to the total weight of the composition.

The composition according to the invention is in the form of an oil-in-water nanoemulsion of which the particles (or drops) of oil preferably have a volume-average size of less than <NUM>, preferentially of between <NUM> and <NUM>, and better still between <NUM> and <NUM>, and even better still between <NUM> and <NUM>.

The volume-average size of the particles (or oil drops) may be determined in particular according to the known laser diffraction method. By way of apparatus that can be used for this determination, mention may be made of the particle size analyser of the brand Malvern, model Zetasizer Nano ZS, equipped with a standard laser having a power of <NUM> mW, and at a wavelength of <NUM>. This device is also equipped with a correlator (<NUM> ns to <NUM>, <NUM> channels maxi.

In addition, the composition according to the invention has very low polydispersity, i.e. the particles have a very homogeneous size. The particles present in the composition according to the invention are liquid oil (or oily phase) particles within the continuous aqueous phase.

The composition according to the invention is advantageously in gel form.

Preferably, the composition has a translucent to blueish colour, preferably a blueish colour.

The composition according to the invention may have a viscosity ranging for example from <NUM> to <NUM> mPa. s (<NUM> to <NUM> cPoises), and preferably from <NUM> to <NUM> mPa. s (<NUM> to <NUM> cPoises), the viscosity being measured at ambient temperature (<NUM>) with a Rheomat RM180 (generally using spindle <NUM> or <NUM>).

The invention also relates to a process for the cosmetic treatment of keratin materials, in particular human keratin fibres such as the hair, in which the composition according to the invention is applied to said fibres.

Thus, an effective quantity of the composition may be applied to the keratin fibres, followed by an optional rinse after an optional leave-on time.

Preferably, the treatment process comprises a rinsing step after the application of the composition according to the invention.

The invention also relates to the use of said composition for the cosmetic treatment of keratin materials, in particular human keratin fibres such as the hair.

The compositions according to the invention may be used, for example, as a cleaning composition, such as a pre-treatment or posttreatment composition for shampoos, dyes, permanent waves, bleaches and straighteners.

In a preferred manner, the composition according to the invention is a rinse-off or leave-on conditioner care product.

More preferentially, the composition according to the invention is a rinse-off conditioner care product.

The examples that follow illustrate the present invention, and should not in any way be considered as limiting the invention.

In the examples that follow, the amounts are indicated as weight percentages relative to the total weight of the composition (am: active material).

The comparative composition A and the compositions B and C according to the invention are prepared according to the conventional methods.

The percentages are indicated in weight of active material.

The compositions B and C according to the invention exhibit good stability over time, better than the comparative composition A, both at ambient temperature and at a temperature of <NUM>.

The compositions are applied to locks of hair pre-washed with a standard shampoo, rinsed and wrung dry.

After a leave-on time, the locks of hair are rinsed and then dried.

Claim 1:
Cosmetic composition in the form of an oil-in-water nanoemulsion comprising:
(i) at least <NUM>% by weight, relative to the total weight of the composition, of one or more fatty substances including at least one plant oil,
(ii) one or more cationic surfactants chosen from:
- those corresponding to general formula (I) below:
<CHM>
in which the groups R<NUM> to R<NUM>, which may be identical or different, represent a linear or branched aliphatic group comprising from <NUM> to <NUM> carbon atoms, at least one of the groups R<NUM> to R<NUM> denoting a linear or branched aliphatic radical comprising from <NUM> to <NUM> carbon atoms, preferably from <NUM> to <NUM> carbon atoms,
X- is an anion chosen from the group of halides, phosphates, acetates, lactates, (C<NUM>-C<NUM>)alkyl sulfates, (C<NUM>-C<NUM>)alkylsulfonates or (C<NUM>-C<NUM>)alkylarylsulfonates,
- quaternary ammonium salts of imidazoline,
- di- or tri-quaternary ammonium salts,
- quaternary ammonium salts containing at least one ester function, and
(iii) water.