FR3152399A1 - Cosmetic treatment process - Google Patents

Abstract

The present invention relates to a cosmetic treatment process, preferably hair treatment, for keratin fibres, in particular hair, comprising: - a step of applying a cosmetic composition comprising organosilanes, then - a washing step comprising the application of a cosmetic composition comprising anionic and/or amphoteric surfactants, then - a step of applying a cosmetic composition comprising amino acids and hydroxylated (poly)carboxylic acids, comprising 2 to 8 carbon atoms, and/or their salts.

Description

Cosmetic treatment process

The present invention relates to a method for cosmetic treatment of hair, consisting of applying in a sequential manner, a pre-shampoo cosmetic composition, then a shampoo-type washing cosmetic composition, and finally a conditioner-type composition.

Hair can be weakened or damaged by the action of external atmospheric agents such as light and bad weather, or by mechanical or chemical treatments such as brushing, combing, dyeing, bleaching, perming and/or straightening. To remedy these disadvantages, it is common to use hair care products that condition the hair. These hair care compositions can be conditioning shampoos or conditioners that can be in the form of gels, hair lotions or creams of varying thickness.

To improve the cosmetic properties of these compositions, it is known to introduce conditioning agents into them, intended mainly to repair or limit the harmful or undesirable effects induced by the various treatments or attacks that the hair fibers undergo, more or less repeatedly.

For this purpose, it has already been proposed to use, among other things, organosilanes in cosmetic care compositions, to give the hair satisfactory conditioning properties. Such compositions are, for example, described in patent applications FR2910276, EP2343042 and EP2111848.

However, the care compositions described in these documents provide conditioning and detangling properties that do not last long enough over time. In fact, these properties generally do not withstand washing sufficiently and tend to diminish after the first shampoo. In other words, even if these hair care compositions allow suitable results to be obtained during and immediately after their use, it has been observed that these effects tend to disappear as the hair is washed; it is then necessary to regularly renew the application of hair care products to maintain adequate conditioning effects.

Application WO2016/083578 then proposed a hair care composition capable of providing conditioning properties that are not only satisfactory but also lasting after washing, for example lasting at least after 3 shampoos. This care composition comprises the combination of organosilanes, cationic polymers with a high charge density and cationic surfactants.

It has also been proposed, for example by EP2111849, a hair treatment method comprising the sequential application of a composition comprising organosilanes and a hair care or washing composition. This document describes in particular the use of a composition comprising an organosilane as a pre-shampoo, i.e. applied to the hair before washing with a shampoo comprising at least one anionic surfactant and one amphoteric surfactant. This method makes it possible in particular to obtain soft and smooth hair, which detangles well.

However, it is still possible to improve the performance provided by such compositions, particularly in terms of providing strength (denser, stiffer hair), while retaining a certain lightness (tonic and loose hair) as well as in terms of cosmetic properties such as detangling and smoothing to the touch; and this both immediately, when applying the composition to the hair (at T0), but also in a lasting manner, that is to say after several shampoos, for example lasting after 2 to 4 shampoos.

This is the objective sought by the present invention.

The present invention therefore relates to a process for the cosmetic treatment, preferably hair treatment, of keratin fibers, in particular hair, in particular human hair, comprising:

- a step (i) of application to said keratin fibers of a cosmetic composition A comprising one or more organosilanes, then

- a step (ii) of washing said keratin fibers, comprising the application of a cosmetic washing composition B comprising one or more anionic surfactants and/or one or more amphoteric surfactants, then

- a step (iii) of application to said keratin fibers of a cosmetic composition C comprising one or more amino acid type compounds and one or more hydroxylated carboxylic (poly)acids, comprising 2 to 8 carbon atoms, and/or their salts.

The process according to the invention makes it possible to provide strength and resistance to the hair, resulting in a visible strengthening of the fiber, thus leading in particular to a reduction in hair breakage during subsequent styling or brushing steps and/or to a reduction in the presence of split ends at the ends of the hair.

In addition, the cosmetic properties of the fiber, such as detangling, smooth feel and elasticity, are improved.

These properties can be retained for subsequent shampoos, for example for at least 3 shampoos.

The cosmetic treatment method according to the invention therefore comprises a step (i) comprising the application to the hair of a cosmetic composition A as defined below. This composition A is used as a pre-shampoo (before using a shampoo).

This step may or may not be followed by a break, for example a break of 1 to 15 minutes, especially 2 to 5 minutes.

This step may also optionally be followed by a rinsing step, for example with water, before carrying out step (ii). Preferably, said step (i) is not followed by a rinsing step.

The cosmetic treatment process, in particular hair treatment, according to the invention also comprises a washing step (ii), consisting of the application to the hair of a cosmetic washing composition B as defined below.

This step may or may not be followed by a pause step, for example a pause time of 1 to 15 minutes, especially 2 to 5 minutes. It may also be followed by a rinsing step, for example with water.

Preferably, the method according to the invention comprises an intermediate rinsing step between steps (ii) and (iii).

The cosmetic treatment process, in particular hair treatment, according to the invention also comprises a step (iii) consisting of the application to the hair of a cosmetic composition C as defined below, and comprising one or more amino acid type compounds and one or more hydroxylated (poly)carboxylic acids, comprising 2 to 8 carbon atoms, and/or their salts.

This step may or may not be followed by a pause step, for example a pause time of 1 to 15 minutes, in particular 2 to 5 minutes. It may also be followed by a rinsing step, for example with water; and/or a drying step, for example using a hair dryer or in the open air.

Preferably, the method according to the invention comprises a rinsing step and a drying step, after step (iii).

The application step (i) of composition A and the washing step (ii) with composition B are carried out successively, or sequentially, which means that the application step (i) is carried out before the washing step (ii), intermediate steps, for example pausing and/or rinsing, may be present between these two steps.

The time separating said step (i) of applying composition A (or pre-shampoo) from step (ii) of washing the hair is a maximum of 60 minutes; it may for example be between 30 seconds and 60 minutes, in particular between 1 and 30 minutes, or even between 2 and 20 minutes, even better between 3 and 15 minutes, and particularly between 4 and 10 minutes.

The washing step (ii) and the step (iii) of applying composition C are carried out successively, or sequentially, which means that the washing step (ii) is carried out before the application step (iii), intermediate steps, for example pausing and/or rinsing, may be present between these two steps.

The time separating said washing step (ii) from step (iii) of applying composition C is a maximum of 60 minutes; it may for example be between 30 seconds and 60 minutes, in particular between 1 and 30 minutes, or even between 2 and 20 minutes, even better between 3 and 15 minutes, and particularly between 4 and 10 minutes.

The process according to the invention advantageously provides visible reinforcement of the fiber (= added strength) and instant detangling, particularly on damp hair, and this in a way that lasts for subsequent shampoos, for example for at least 3 shampoos.

The invention therefore also relates to the use of said process for the visible strengthening of the fiber (= adding strength) and/or for improving detangling, in particular on damp hair, and this advantageously in a way that remains after subsequent shampoos, for example for at least 3 shampoos.

In this description, the expression "at least one" is equivalent to the expression "one or more" and may be substituted therefor; the expression "between x and y" is equivalent to the expression "ranging from x to y" and may be substituted therefor, and implies that the limits are included.

A/ Step (i) of application

The cosmetic treatment method according to the invention therefore comprises a step (i) of application to said keratin fibers of a cosmetic composition A comprising one or more organosilanes.

This cosmetic, or even hair, composition can be described as a pre-shampoo.

1/ Organosilanes

Composition A used according to the process of the invention comprises one or more organosilanes.

The organosilane(s) are preferably chosen from the compounds of formula (I) and/or their oligomers and/or their hydrolysis products:

R1Si(OR2)z(R3)x(OH)y (I)

in which:

- R1 is a C1-C22, in particular C2-C20, linear or branched, saturated or unsaturated, cyclic or acyclic hydrocarbon chain, which may be substituted by a group chosen from the amine groups NH2 or NHR (R being a linear or branched C1-C20, in particular C1-C6, alkyl, or a C3-C40 cycloalkyl or a C6-C30 aromatic radical); the hydroxy group (OH), a thiol group, an aryl group (more particularly benzyl) substituted or not by an NH2 or NHR group; R1 may be interrupted by a heteroatom (O, S, NH) or a carbonyl group (CO);

- R2 and R3, identical or different, represent an alkyl group, linear or branched, comprising from 1 to 6 carbon atoms,

- y denotes an integer ranging from 0 to 3,

- z denotes an integer ranging from 0 to 3, and

- x denotes an integer ranging from 0 to 2, with z+x+y=3.

By oligomer is meant the polymerization products of compounds of formula (I) containing from 2 to 10 silicon atoms.

Preferably, R1 is a linear or branched, saturated, C1-C22, in particular C1-C12, hydrocarbon chain, preferably linear, which can be substituted by an amine group NH2 or NHR (R = C1-C20, in particular C1-C6 alkyl).

Better still, R1 is a C1-C12, in particular C2-C6, linear or branched, saturated hydrocarbon chain, substituted by an NH2 amine group. Preferably, R1 represents a C2-C6, preferably C2-C4, aminoalkyl group.

Preferably, R2 represents an alkyl group comprising from 1 to 4 carbon atoms, better still a linear alkyl group comprising from 1 to 4 carbon atoms, and preferably the ethyl group.

Preferably z varies from 1 to 3. Preferably, y=0. Preferably z = 3, and therefore x=y=0.

Preferably, the organosilanes used in the context of the invention correspond to formula (I) in which R1 is a C1-C12, in particular C2-C6, linear or branched, saturated hydrocarbon chain, substituted by an amine group NH2, R2 represents an alkyl group comprising from 1 to 4 carbon atoms, and z = 3 (and therefore x=y=0).

Preferably, composition A according to the invention comprises one or more organosilanes chosen from methyltriethoxysilane (MTES), octyltriethoxysilane (OTES), dodecyltriethoxysilane, octadecyltriethoxysilane, hexadecyltriethoxysilane, 3-aminopropyl triethoxysilane (APTES); 2-aminoethyltriethoxysilane (AETES), 3-aminopropyl methyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, 3-(m-aminophenoxy) propyltrimethoxysilane, p-aminophenyltrimethoxysilane, N-(2-aminoethyl-aminomethyl)-phenethyltrimethoxysilane, and their oligomers, and/or their mixtures; and more particularly chosen from methyltriethoxysilane (MTES) and 3-aminopropyltriethoxysilane (APTES) and their oligomers, their hydrolysis products and/or their mixtures; and even better chosen from 3-aminopropyltriethoxysilane (APTES), its oligomers and/or its hydrolysis products.

Preferably, the organosilane(s) are present in composition A according to the invention in a total content of at least 6% by weight relative to the total weight of the composition, preferably at a total content ranging from 6 to 20% by weight, preferentially from 7 to 15% by weight, better still from 8 to 13% by weight, relative to the total weight of the composition.

Preferably, the organosilane(s) corresponding to formula (I) in which R1 is a C1-C12, in particular C2-C6, linear or branched, saturated hydrocarbon chain substituted by an amine group NH2, R2 represents an alkyl group comprising from 1 to 4 carbon atoms, and z = 3 (and therefore x=y=0) are present in composition A according to the invention in a total content of at least 6% by weight relative to the total weight of the composition, preferably at a total content ranging from 6 to 20% by weight, preferentially from 7 to 15% by weight, better still from 8 to 13% by weight, relative to the total weight of the composition.

Preferably, the organosilane(s) chosen from 3-aminopropyltriethoxysilane (APTES), its oligomers and/or its hydrolysis products are present in composition A according to the invention in a total content of at least 6% by weight relative to the total weight of the composition, preferably at a total content ranging from 6 to 20% by weight, preferentially from 7 to 15% by weight, better still from 8 to 13% by weight, relative to the total weight of the composition.

2/ Cationic polymers

The cosmetic composition A used in step (i) may advantageously comprise one or more cationic polymers.

The term "cationic polymer" means any non-silicone polymer (not containing a silicon atom) containing cationic groups and/or groups which can be ionized into cationic groups, and not containing anionic groups and/or groups which can be ionized into anionic groups.

The cationic polymers that can be used preferably have a cationic charge density greater than or equal to 4 milliequivalents/gram (meq/g), better still greater than or equal to 5 meq/g, or even ranging from 5 to 20 meq/g.

The cationic charge density of a polymer corresponds to the number of moles of cationic charges per unit mass of polymer under conditions where it is fully ionized. It can be determined by calculation if the structure of the polymer is known, i.e. the structure of the monomers constituting the polymer and their molar or weight proportion. It can also be determined experimentally by the Kjeldahl method.

The cationic polymers that can be used preferably have a weight-average molar mass (Mw) of between 500 and 5.10 ⁶ approximately, preferably of between 10 ³ and 3.10 ⁶ approximately.

The cationic polymers that can be used can be associative or not, preferably non-associative.

The term "associative polymer" means an amphiphilic polymer capable, in an aqueous medium, of reversibly associating with itself or with other molecules. It generally comprises in its chemical structure at least one hydrophilic zone, or group, and at least one hydrophobic zone, or group. In particular, the hydrophobic group may be a fatty hydrocarbon chain such as a linear or branched alkyl, linear or branched arylalkyl, linear or branched alkylaryl group comprising at least 8 carbon atoms, preferably 8 to 30 carbon atoms, better still 12 to 24 carbon atoms.

Among the cationic polymers, we can cite:

(1) homopolymers or copolymers derived from acrylic or methacrylic esters or amides and comprising at least one of the units of the following formula:

in which:

- R3, identical or different, denote a hydrogen atom or a CH3 radical;

- A, identical or different, represent a divalent alkyl group, linear or branched, of 1 to 6 carbon atoms, preferably 2 or 3 carbon atoms or a hydroxyalkyl group of 1 to 4 carbon atoms;

- R4, R5, R6, identical or different, represent an alkyl group having from 1 to 18 carbon atoms or a benzyl radical; preferably an alkyl group having from 1 to 6 carbon atoms;

- R1 and R2, identical or different, represent a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms, preferably methyl or ethyl;

- X denotes an anion derived from a mineral or organic acid such as a methosulfate anion or a halide such as chloride or bromide.

The copolymers of family (1) may also contain one or more units derived from comonomers which may be chosen from the family of acrylamides, methacrylamides, diacetone acrylamides, acrylamides and methacrylamides substituted on the nitrogen by lower alkyls (C1-C4), esters of acrylic or methacrylic acids, vinyllactams such as vinylpyrrolidone or vinylcaprolactam, vinyl esters.

Among these copolymers of family (1), we can cite:

- copolymers of acrylamide and dimethylaminoethyl methacrylate quaternized with dimethyl sulfate or with a dimethyl halide, such as that sold under the name HERCOFLOC by the company HERCULES,

- copolymers of acrylamide and methacryloyloxyethyltrimethylammonium chloride, such as those sold under the name BINA QUAT P 100 by the company CIBA GEIGY,

- the copolymer of acrylamide and methacryloyloxyethyltrimethylammonium methosulfate, such as that sold under the name RETEN by the company HERCULES,

- vinylpyrrolidone/dialkylaminoalkyl acrylate or methacrylate copolymers, quaternized or not, such as the products sold under the name "GAFQUAT" by the company ISP such as for example "GAFQUAT 734" or "GAFQUAT 755" or the products called "COPOLYMER 845, 958 and 937";

- dimethylaminoethyl methacrylate/vinylcaprolactam/vinylpyrrolidone terpolymers, such as the product sold under the name GAFFIX VC 713 by the company ISP,

- vinylpyrrolidone/methacrylamidopropyldimethylamine copolymers, such as those marketed under the name STYLEZE CC 10 by ISP;

- quaternized vinylpyrrolidone/dimethylaminopropyl methacrylamide copolymers, such as the product sold under the name "GAFQUAT HS 100" by the company ISP,

- polymers, preferably crosslinked, of methacryloyloxyalkyl(C1-C4)trialkyl(C1-C4)ammonium salts such as polymers obtained by homopolymerization of dimethylaminoethylmethacrylate quaternized with methyl chloride, or by copolymerization of acrylamide with dimethylaminoethylmethacrylate quaternized with methyl chloride, the homo- or copolymerization being followed by crosslinking with an olefinically unsaturated compound, in particular methylene bisacrylamide. It is more particularly possible to use a crosslinked acrylamide/methacryloyloxyethyltrimethylammonium chloride copolymer (20/80 by weight) in the form of a dispersion comprising 50% by weight of said copolymer in mineral oil. This dispersion is marketed under the name "SALCARE® SC 92" by the company CIBA. A crosslinked homopolymer of methacryloyloxyethyltrimethylammonium chloride comprising approximately 50% by weight of the homopolymer in mineral oil or in a liquid ester can also be used. These dispersions are marketed under the names "SALCARE® SC 95" and "SALCARE® SC 96" by the company CIBA.

(2) cationic polysaccharides, in particular celluloses and cationic galactomannan gums. Among the cationic polysaccharides, mention may be made more particularly of cellulose ether derivatives comprising quaternary ammonium groups, cationic cellulose copolymers or cellulose derivatives grafted with a water-soluble quaternary ammonium monomer and cationic galactomannan gums.

Cellulose ether derivatives containing quaternary ammonium groups are described in particular in FR1492597, and mention may be made of the polymers marketed under the name "UCARE POLYMER JR" (JR 400 LT, JR 125, JR 30M) or "LR" (LR 400, LR 30M) by the company AMERCHOL. These polymers are also defined in the CTFA dictionary as quaternary ammoniums of hydroxyethylcellulose having reacted with an epoxide substituted by a trimethylammonium group.

Cationic cellulose copolymers or cellulose derivatives grafted with a water-soluble quaternary ammonium monomer are described in particular in patent US4131576, and hydroxyalkylcelluloses may be mentioned, such as hydroxymethyl-, hydroxyethyl- or hydroxypropyl celluloses grafted in particular with a salt of methacryloylethyl trimethylammonium, methacrylamidopropyl trimethylammonium, dimethyl-diallylammonium. The marketed products meeting this definition are more particularly the products sold under the name "Celquat L 200" and "Celquat H 100" by the National Starch Company.

Cationic galactomannan gums are described more particularly in patents US3589578 and US4031307, and guar gums comprising cationic trialkylammonium groups may be mentioned. For example, guar gums modified with a salt (for example a chloride) of 2,3-epoxypropyltrimethylammonium are used. Such products are marketed in particular under the names JAGUAR C13 S, JAGUAR C 15, JAGUAR C 17 or JAGUAR C162 by the company RHODIA.

(3) polymers consisting of piperazinyl units and divalent alkylene or hydroxyalkylene radicals with linear or branched chains, optionally interrupted by oxygen, sulfur, nitrogen atoms or by aromatic or heterocyclic rings, as well as the oxidation and/or quaternization products of these polymers.

(4) water-soluble polyaminoamides, prepared in particular by polycondensation of an acidic compound with a polyamine; these polyaminoamides may be crosslinked by an epihalohydrin, a diepoxide, a dianhydride, an unsaturated dianhydride, a bis-unsaturated derivative, a bis-halohydrin, a bis-azetidinium, a bis-haloacyldiamine, an alkyl bis-halide or by an oligomer resulting from the reaction of a bifunctional compound reactive with a bis-halohydrin, a bis-azetidinium, a bis-haloacyldiamine, an alkyl bis-halide, an epihalohydrin, a diepoxide or a bis-unsaturated derivative; the crosslinking agent being used in proportions ranging from 0.025 to 0.35 mole per amine group of the polyaminoamide; these polyaminoamides can be alkylated or, if they comprise one or more tertiary amine functions, quaternized.

(5) polyaminoamide derivatives resulting from the condensation of polyalkylene polyamines with polycarboxylic acids followed by alkylation by bifunctional agents. Examples that may be mentioned are adipic acid-diacoylaminohydroxyalkyldialoylene triamine polymers in which the alkyl radical contains 1 to 4 carbon atoms and preferably denotes methyl, ethyl, propyl. Among these derivatives, mention may be made more particularly of adipic acid/dimethylaminohydroxypropyl/diethylene triamine polymers sold under the name "Cartaretine F, F4 or F8" by the company Sandoz.

(6) polymers obtained by reacting a polyalkylene polyamine comprising two primary amine groups and at least one secondary amine group with a dicarboxylic acid chosen from diglycolic acid and saturated aliphatic dicarboxylic acids having from 3 to 8 carbon atoms; the molar ratio between the polyalkylene polyamine and the dicarboxylic acid preferably being between 0.8:1 and 1.4:1; the resulting polyaminoamide being reacted with epichlorohydrin in a molar ratio of epichlorohydrin relative to the secondary amine group of the polyaminoamide preferably between 0.5:1 and 1.8:1. Polymers of this type are marketed in particular under the name "Hercosett 57" by the company Hercules Inc. or under the name "PD 170" or "Delsette 101" by the company Hercules in the case of the adipic acid/epoxypropyl/diethylene-triamine copolymer.

(7) cyclopolymers of alkyl diallyl amine or dialkyl diallyl ammonium such as homopolymers or copolymers comprising as the main constituent of the chain units corresponding to formulae (I) or (II):

in which

- k and t are equal to 0 or 1, the sum k + t being equal to 1;

- R12 denotes a hydrogen atom or a methyl radical;

- R10 and R11, independently of one another, denote a C1-C6 alkyl group, a C1-C5 hydroxyalkyl group, a C1-C4 amidoalkyl group; or R10 and R11 may denote, together with the nitrogen atom to which they are attached, a heterocyclic group such as piperidinyl or morpholinyl; R10 and R11, independently of one another, preferably denote a C1-C4 alkyl group;

- Y ^- is an anion such as bromide, chloride, acetate, borate, citrate, tartrate, bisulfate, bisulfite, sulfate, phosphate.

Mention may be made more particularly of the homopolymer of salts (for example chloride) of dimethyldiallylammonium, for example sold under the name "MERQUAT 100" by the company NALCO, and the copolymers of salts (for example chloride) of diallyldimethylammonium and acrylamide marketed in particular under the name "MERQUAT 550" or "MERQUAT 7SPR".

(8) quaternary diammonium polymers comprising recurring units of formula:

in which:

- R13, R14, R15 and R16, identical or different, represent aliphatic, alicyclic or arylaliphatic radicals comprising from 1 to 20 carbon atoms or C1-C12 hydroxyalkylaliphatic radicals,

or R13, R14, R15 and R16, together or separately, constitute with the nitrogen atoms to which they are attached heterocycles possibly comprising a second heteroatom other than nitrogen

or R13, R14, R15 and R16 represent a linear or branched C1-C6 alkyl radical substituted by a nitrile, ester, acyl, amide group or -CO-O-R17-D or -CO-NH-R17-D where R17 is an alkylene and D a quaternary ammonium group;

- A1 and B1 represent divalent polymethylene groups comprising from 2 to 20 carbon atoms, linear or branched, saturated or unsaturated, and which may contain, linked to or intercalated in the main chain, one or more aromatic rings, or one or more oxygen or sulfur atoms or sulfoxide, sulfone, disulfide, amino, alkylamino, hydroxyl, quaternary ammonium, ureido, amide or ester groups, and

- X ^- denotes an anion derived from a mineral or organic acid;

it being understood that A1, R13 and R15 can form with the two nitrogen atoms to which they are attached a piperazine ring;

furthermore if A1 denotes a linear or branched, saturated or unsaturated alkylene or hydroxyalkylene radical, B1 can also denote a group (CH2)n-CO-D-OC-(CH2)p-, with n and p, identical or different, being integers varying from 2 to 20, and D denoting:

(a) a glycol residue of formula -O-Z-O-, where Z denotes a linear or branched hydrocarbon radical or a group corresponding to one of the following formulae: -(CH2CH2O)x-CH2CH2- and -[CH2CH(CH3)O]y-CH2CH(CH3)- where x and y denote an integer from 1 to 4, representing a defined and unique degree of polymerization or any number from 1 to 4 representing an average degree of polymerization;

(b) a bis-secondary diamine residue such as a piperazine derivative;

(c) a bis-primary diamine residue of formula -NH-Y-NH- where Y denotes a linear or branched hydrocarbon radical, or the divalent radical -CH2-CH2-S-S-CH2-CH2-;

d) a ureylene group of formula -NH-CO-NH-.

Preferably, X ^- is an anion such as chloride or bromide. These polymers have a number average molar mass (Mn) generally between 1000 and 100000.

We can cite more particularly polymers which are made up of recurring units corresponding to the formula:

in which R1, R2, R3 and R4, identical or different, denote an alkyl or hydroxyalkyl radical having from 1 to 4 carbon atoms, n and p are whole numbers varying from 2 to 20, and X- is an anion derived from a mineral or organic acid.

A particularly preferred compound of formula (IV) is that for which R1, R2, R3 and R4 represent a methyl radical, n=3, p=6 and X = Cl, called Hexadimethrine chloride according to the INCI nomenclature (CTFA).

(9) quaternary polyammonium polymers comprising units of formula (V):

in which:

- R18, R19, R20 and R21, which may be identical or different, represent a hydrogen atom or a methyl, ethyl, propyl, β-hydroxyethyl, β-hydroxypropyl or -CH2CH2(OCH2CH2)pOH radical, where p is equal to 0 or to an integer between 1 and 6, provided that R18, R19, R20 and R21 do not simultaneously represent a hydrogen atom,

- r and s, identical or different, are whole numbers between 1 and 6,

- q is equal to 0 or to an integer between 1 and 34,

- X- denotes an anion such as a halide,

- A denotes a divalent radical of a dihalide or preferably represents -CH2-CH2-O-CH2-CH2-.

Examples include the products "Mirapol® A 15", "Mirapol® AD1", "Mirapol® AZ1" and "Mirapol® 175" sold by the company Miranol.

(10) Quaternary polymers of vinylpyrrolidone and vinylimidazole such as, for example, the products marketed under the names Luviquat® FC 905, FC 550 and FC 370 by the company B.A.S.F.

(11) Polyamines such as Polyquart® H sold by COGNIS, referenced under the name “POLYETHYLENEGLYCOL (15) TALLOW POLYAMINE” in the CTFA dictionary.

(12) polymers comprising in their structure:

(a) one or more patterns corresponding to the following formula (A):

(b) optionally one or more patterns corresponding to the following formula (B):

In other words, these polymers can be chosen in particular from homo- or copolymers comprising one or more units derived from vinylamine and possibly one or more units derived from vinylformamide.

Preferably, these cationic polymers are chosen from polymers comprising, in their structure, from 5 to 100 mol% of units corresponding to formula (A) and from 0 to 95 mol% of units corresponding to formula (B), preferably from 10 to 100 mol% of units corresponding to formula (A) and from 0 to 90 mol% of units corresponding to formula (B).

These polymers can be obtained, for example, by partial hydrolysis of polyvinylformamide. This hydrolysis can be carried out in an acidic or basic medium.

The weight-average molecular mass of said polymer, measured by light diffraction, can vary from 1,000 to 3,000,000 g/mol, preferably from 10,000 to 1,000,000 and more particularly from 100,000 to 500,000 g/mol.

Polymers comprising units of formula (A) and possibly units of formula (B) are sold in particular under the name LUPAMIN by the company BASF, such as, for example, and in a non-limiting manner, the products offered under the names LUPAMIN 9095, LUPAMIN 5095, LUPAMIN 1095, LUPAMIN 9030 (or LUVIQUAT 9030) and LUPAMIN 9010.

Particularly preferred are cationic polymers chosen from those of families (1), (2), (7) and (10) cited above, better still those of families (1), (2) and (7).

Among the associative cationic polymers that can be used, we can cite, alone or in a mixture:

- (A) cationic associative polyurethanes, which can be represented by the following general formula (Ia): R-X-(P)n-[L-(Y)m]r-L'-(P')p-X'-R'

in which:

R and R’, identical or different, represent a hydrophobic group or a hydrogen atom;

X and X', identical or different, represent a group comprising an amine function carrying or not a hydrophobic group, or the group L";

L, L’ and L", identical or different, represent a group derived from a diisocyanate;

P and P’, identical or different, represent a group comprising an amine function carrying or not a hydrophobic group;

Y represents a hydrophilic group;

r is an integer between 1 and 100 inclusive, preferably between 1 and 50 inclusive and in particular between 1 and 25 inclusive,

n, m, and p are each independently of the others between inclusively 0 and 1000,

the molecule containing at least one protonated or quaternized amine function and at least one hydrophobic group.

Preferably, the only hydrophobic groups are the R and R' groups at the chain ends.

A preferred family of cationic associative polyurethanes is that corresponding to formula (Ia) described above in which:

R and R’ both independently represent a hydrophobic group,

X, X’ each represent a group L’’,

n and p are integers which are between 1 and 1000 inclusive and L, L’, L’’, P, P’, Y and m have the meaning indicated above.

Another preferred family of cationic associative polyurethanes is that corresponding to formula (Ia) above in which:

- n=p=0 (the polymers do not contain units derived from an amine-functional monomer, incorporated into the polymer during polycondensation),

- the protonated amine functions result from the hydrolysis of excess isocyanate functions at the end of the chain, followed by the alkylation of the primary amine functions formed by alkylating agents with a hydrophobic group, i.e. compounds of type RQ or R'Q, in which R and R' are as defined above and Q denotes a leaving group such as a halide or a sulfate.

Yet another preferred family of cationic associative polyurethanes is that corresponding to formula (Ia) above in which:

R and R’ both independently represent a hydrophobic group,

X and X’ both independently represent a group comprising a quaternary amine,

n = p = 0, and

L, L’, Y and m have the meaning indicated above.

The number average molecular weight (Mn) of the cationic associative polyurethanes is preferably between inclusively 400 and 500,000, in particular between inclusively 1000 and 400,000 and ideally between inclusively 1000 and 300,000.

By hydrophobic group is meant a radical or polymer with a hydrocarbon chain, saturated or not, linear or branched, which may contain one or more heteroatoms such as P, O, N, S, or a radical with a perfluorinated or silicone chain. When it designates a hydrocarbon radical, the hydrophobic group comprises at least 10 carbon atoms, preferably from 10 to 30 carbon atoms, in particular from 12 to 30 carbon atoms and more preferably from 18 to 30 carbon atoms.

Preferably, the hydrocarbon group comes from a monofunctional compound.

For example, the hydrophobic group can be derived from a fatty alcohol such as stearyl alcohol, dodecyl alcohol, decyl alcohol. It can also designate a hydrocarbon polymer such as, for example, polybutadiene.

When X and/or X' denote a group comprising a tertiary or quaternary amine, X and/or X' may represent one of the following formulas:

in which:

R2 represents an alkylene radical having from 1 to 20 carbon atoms, linear or branched, comprising or not a saturated or unsaturated cycle, or an arylene radical, one or more of the carbon atoms being able to be replaced by a heteroatom chosen from N, S, O, P;

R1 and R3, identical or different, denote a linear or branched C1-C30 alkyl or alkenyl radical, an aryl radical, at least one of the carbon atoms being able to be replaced by a heteroatom chosen from N, S, O, P;

A- is a physiologically acceptable anionic counterion such as a halide like chloride or bromide, or a mesylate.

The groups L, L' and L" represent a group of formula:

in which:

Z represents –O-, -S- or –NH-; and

R4 represents an alkylene radical having from 1 to 20 carbon atoms, linear or branched, comprising or not a saturated or unsaturated cycle, an arylene radical, one or more of the carbon atoms being able to be replaced by a heteroatom chosen from N, S, O and P.

The groups P and P', comprising an amine function, can represent at least one of the following formulas:

in which:

R5 and R7 have the same meanings as R2 defined previously;

R6, R8 and R9 have the same meanings as R1 and R3 defined previously;

R10 represents a linear or branched alkylene group, optionally unsaturated and which may contain one or more heteroatoms chosen from N, O, S and P,

and A- is a physiologically acceptable anionic counterion such as halide like chloride or bromide or mesylate.

As for the meaning of Y, a hydrophilic group is understood to mean a polymeric or non-polymeric water-soluble group.

Examples of non-polymers include ethylene glycol, diethylene glycol and propylene glycol.

When, in accordance with a preferred embodiment, it is a hydrophilic polymer, examples that may be mentioned are polyethers, sulfonated polyesters, sulfonated polyamides, or a mixture of these polymers. Preferably, the hydrophilic compound is a polyether and in particular a poly(ethylene oxide) or poly(propylene oxide).

The cationic associative polyurethanes of formula (Ia) according to the invention are formed from diisocyanates and various compounds having labile hydrogen functions. The labile hydrogen functions may be alcohol, primary or secondary amine or thiol functions giving, after reaction with the diisocyanate functions, respectively polyurethanes, polyureas and polythioureas. The term "polyurethanes" of the present invention encompasses these three types of polymers, namely polyurethanes themselves, polyureas and polythioureas as well as copolymers thereof.

A first type of compound used in the preparation of the polyurethane of formula (Ia) is a compound comprising at least one amine-functional unit. This compound may be multifunctional, but preferably the compound is difunctional, that is to say that according to a preferred embodiment, this compound comprises two labile hydrogen atoms carried for example by a hydroxyl, primary amine, secondary amine or thiol function. It is also possible to use a mixture of multifunctional and difunctional compounds in which the percentage of multifunctional compounds is low.

As previously stated, this compound may contain more than one amine-functional unit. In this case, it is a polymer bearing a repetition of the amine-functional unit.

This type of compound can be represented by one of the following formulas:

HZ-(P)n-ZH, or HZ-(P')p-ZH, in which Z, P, P', n and p are as defined above.

Examples include N-methyldiethanolamine, N-tert-butyldiethanolamine and N-sulfoethyldiethanolamine.

The second compound used in the preparation of the polyurethane of formula (Ia) is a diisocyanate corresponding to the formula:

O=C=N-R4-N=C=O in which R4 is defined above.

Examples include methylenediphenyldiisocyanate, methylenecyclohexanediisocyanate, isophoronediisocyanate, toluenediisocyanate, naphthalenediisocyanate, butanediisocyanate, hexanediisocyanate.

A third compound used in the preparation of the polyurethane of formula (Ia) is a hydrophobic compound intended to form the terminal hydrophobic groups of the polymer of formula (Ia).

This compound consists of a hydrophobic group and a labile hydrogen function, for example a hydroxyl, primary or secondary amine, or thiol function.

For example, this compound may be a fatty alcohol, such as stearyl alcohol, dodecyl alcohol, decyl alcohol. When this compound comprises a polymer chain, it may be, for example, alpha-hydroxyl hydrogenated polybutadiene.

The hydrophobic group of the polyurethane of formula (Ia) can also result from the quaternization reaction of the tertiary amine of the compound comprising at least one tertiary amine unit. Thus, the hydrophobic group is introduced by the quaternizing agent. This quaternizing agent is a compound of type RQ or R'Q, in which R and R' are as defined above and Q denotes a leaving group such as a halide, a sulfate, etc.

The cationic associative polyurethane may further comprise a hydrophilic sequence. This sequence is provided by a fourth type of compound used in the preparation of the polymer. This compound may be multifunctional. It is preferably difunctional. It is also possible to have a mixture where the percentage of multifunctional compound is low.

The labile hydrogen functions are alcohol, primary or secondary amine, or thiol functions. This compound can be a polymer terminated at the ends of the chains by one of these labile hydrogen functions.

Examples of non-polymers include ethylene glycol, diethylene glycol and propylene glycol.

When it comes to a hydrophilic polymer, examples that may be mentioned are polyethers, sulfonated polyesters, sulfonated polyamides, or a mixture of these polymers. Preferably, the hydrophilic compound is a polyether and in particular a poly(ethylene oxide) or poly(propylene oxide).

The hydrophilic group denoted Y in formula (Ia) is optional. Indeed, quaternary or protonated amine functional units may be sufficient to provide the solubility or hydrodispersibility required for this type of polymer in an aqueous solution.

Although the presence of a hydrophilic Y group is optional, cationic associative polyurethanes having such a group are preferred.

- (B) quaternized cellulose derivatives, and in particular quaternized celluloses modified by groups comprising at least one fatty chain, such as linear or branched alkyl, linear or branched arylalkyl, linear or branched alkylaryl, preferably linear or branched alkyl, these groups comprising at least 8 carbon atoms, in particular from 8 to 30 carbon atoms, better still from 10 to 24, or even from 10 to 14, carbon atoms; or mixtures thereof.

Preferably, mention may be made of quaternized hydroxyethylcelluloses modified by groups comprising at least one fatty chain, such as linear or branched alkyl, linear or branched arylalkyl, linear or branched alkylaryl, preferably linear or branched alkyl, these groups comprising at least 8 carbon atoms, in particular from 8 to 30 carbon atoms, better still from 10 to 24, or even from 10 to 14, carbon atoms; or mixtures thereof.

Preferably, we can cite hydroxyethylcelluloses of formula (Ib):

in which:

- R represents an ammonium group RaRbRcN+-, Q- in which Ra, Rb, Rc, identical or different, represent a hydrogen atom or a linear or branched alkyl, C1-C30, and Q- represents an anionic counterion such as a halide like a chloride or bromide; preferably an alkyl;

- R’ represents an ammonium group R’aR’bR’cN+-, Q’- in which R’a, R’b, R’c, identical or different, represent a hydrogen atom or a linear or branched alkyl, C1-C30, and Q’- represents an anionic counterion such as a halide like a chloride or bromide; preferably an alkyl;

it being understood that at least one of the radicals Ra, Rb, Rc, R’a, R’b, R’c represents a linear or branched C8-C30 alkyl;

- n, x and y, identical or different, represent an integer between 1 and 10000.

Preferably, in formula (Ib), at least one of the radicals Ra, Rb, Rc, R'a, R'b, R'c represents a linear or branched C8-C30 alkyl; better still C10-C24, or even C10-C14; mention may in particular be made of the dodecyl radical (C12). Preferably, the other radical(s) represent a linear or branched C1-C4 alkyl, in particular methyl.

Preferably, in formula (Ib), only one of the radicals Ra, Rb, Rc, R'a, R'b, R'c represents a linear or branched C8-C30 alkyl; better still C10-C24, or even C10-C14; mention may in particular be made of the dodecyl radical (C12). Preferably, the other radicals represent a linear or branched C1-C4 alkyl, in particular methyl.

Even better, R may be a group selected from –N ⁺ (CH ₃ ) ₃ , Q' ^- and –N ⁺ (C ₁₂ H ₂₅ )(CH ₃ ) ₂ , Q' ^- , preferably a group –N ⁺ (CH ₃ ) ₃ , Q' ^- .

Even better, R' can be a group –N ⁺ (C ₁₂ H ₂₅ )(CH ₃ ) ₂ , Q' ^- .

Aryl radicals preferably denote phenyl, benzyl, naphthyl or anthryl groups.

We can notably cite polymers with INCI names:

- Polyquaternium-24, such as the product QUATRISOFT LM 200®, marketed by the company AMERCHOL/DOW CHEMICAL;

- PG-Hydroxyethylcellulose Cocodimonium Chloride, such as the product CRODACEL QM®;

- PG-Hydroxyethylcellulose Lauryldimonium Chloride (C12 alkyl), such as the product CRODACEL QL® and

- PG-Hydroxyethylcellulose Stearyldimonium Chloride (C18 alkyl) such as the product CRODACEL QS®, marketed by the company CRODA.

Mention may also be made of hydroxyethylcelluloses of formula (Ib) in which R represents trimethylammonium halide and R' represents dimethyldodecylammonium halide, preferably R represents trimethylammonium chloride Cl-,(CH3)3N+- and R' represents dimethyldodecylammonium chloride Cl-,(CH3)2(C12H25)N+-. This type of polymer is known under the INCI name Polyquaternium-67; as commercial products, mention may be made of SOFTCAT POLYMER SL® polymers such as SL-100, SL-60, SL-30 and SL-5 from the company AMERCHOL /DOW CHEMICAL.

More particularly, the polymers of formula (Ib) are those whose viscosity is inclusively between 2000 and 3000 cPs, preferably between 2700 and 2800 cPs. Typically, SOFTCAT POLYMER SL-5 has a viscosity of 2500 cPs, SOFTCAT POLYMER SL-30 has a viscosity of 2700 cPs, SOFTCAT POLYMER SL-60 has a viscosity of 2700 cPs and SOFTCAT POLYMER SL-100 has a viscosity of 2800 cPs.

- (C) cationic polyvinyllactams, in particular those comprising:

-a) at least one vinyllactam or alkylvinyllactam monomer;

-b) at least one monomer of the following structures (Ic) or (IIc):

in which:

- X denotes an oxygen atom or an NR6 radical,

- R1 and R6 denote, independently of one another, a hydrogen atom or a linear or branched C1-C5 alkyl radical,

- R2 denotes a linear or branched C1-C4 alkyl radical,

- R3, R4 and R5 denote, independently of one another, a hydrogen atom, a linear or branched C1-C30 alkyl radical or a radical of formula (IIIc):

- Y, Y1 and Y2 denote, independently of one another, a linear or branched C2-C16 alkylene radical,

- R7 denotes a hydrogen atom, or a linear or branched C1-C4 alkyl radical or a linear or branched C1-C4 hydroxyalkyl radical,

- R8 denotes a hydrogen atom or a linear or branched C1-C30 alkyl radical,

- p, q and r designate, independently of each other, 0 or 1;

- m and n denote, independently of each other, an integer ranging inclusively from 0 to 100,

- x denotes an integer ranging from 1 to 100 inclusive,

- Z denotes an anionic counterion of organic or mineral acid, such as halide like chloride or bromide or mesylate;

provided that:

- at least one of the substituents R3, R4, R5 or R8 denotes a linear or branched C9-C30 alkyl radical,

- if m and/or n is different from zero, then q is equal to 1,

- if m=n=0, then p or q equals 0.

The cationic poly(vinyllactam) polymers according to the invention may be crosslinked or non-crosslinked and may also be block polymers.

Preferably the counterion Z- of the monomers of formula (Ic) is chosen from halide ions, phosphate ions, the methosulfate ion, the tosylate ion.

Preferably R3, R4 and R5 denote, independently of one another, a hydrogen atom or a linear or branched C1-C30 alkyl radical.

More preferably, monomer b) is a monomer of formula (Ic) for which, preferably, m and n are equal to zero.

The vinyllactam or alkylvinyllactam monomer is preferably a compound of structure (IVc):

in which:

- s denotes an integer ranging from 3 to 6,

- R9 denotes a hydrogen atom or a linear or branched C1-C5 alkyl radical,

- R10 denotes a hydrogen atom or a linear or branched C1-C5 alkyl radical,

provided that at least one of the radicals R9 and R10 denotes a hydrogen atom.

Even more preferably, the monomer (IVc) is vinylpyrrolidone.

The cationic poly(vinyllactam) polymers according to the invention may also contain one or more additional monomers, preferably cationic or non-ionic.

As particularly preferred compounds, mention may be made of the following terpolymers comprising at least:

a) a monomer of formula (IVc),

b) a monomer of formula (Ic) in which p=1, m=n=q=0, R3 and R4 denote, independently of each other, a hydrogen atom or a C1-C5 alkyl radical and R5 denotes a linear or branched C9-C24 alkyl radical, and

c) a monomer of formula (IIc) in which p=1, m=n=q=0, R3 and R4 denote, independently of one another, a hydrogen atom or a linear or branched C1-C5 alkyl radical.

Even more preferably, terpolymers comprising, by weight, 40 to 95% of monomer (a), 0.1 to 55% of monomer (c) and 0.25 to 50% of monomer (b) will be used. Such polymers are described in particular in patent application WO-00/68282.

As cationic poly(vinyllactam) polymers according to the invention, the following are used in particular:

- vinylpyrrolidone / dimethylaminopropylmethacrylamide / dodecyldimethylmethacrylamidopropylammonium tosylate terpolymers,

- vinylpyrrolidone / dimethylaminopropylmethacrylamide / cocoyldimethylmethacrylamidopropylammonium tosylate terpolymers,

- vinylpyrrolidone / dimethylaminopropylmethacrylamide / tosylate or lauryldimethylmethacrylamidopropylammonium chloride terpolymers.

The vinylpyrrolidone/dimethylaminopropylmethacrylamide/lauryl dimethylmethacrylamidopropylammonium chloride terpolymer is notably offered by the company ISP under the names Styleze W10® or Styleze W20L® (INCI name Polyquaternium-55).

The molecular weight (Mw) of the cationic poly(vinyllactam) polymers is preferably between 500 and 20,000,000, more particularly between 200,000 and 2,000,000 and preferentially between 400,000 and 800,000.

- (D) cationic polymers obtained by polymerization of a mixture of monomers comprising one or more vinyl monomers substituted by one or more amino groups, one or more hydrophobic non-ionic vinyl monomers, and one or more associative vinyl monomers, as described in patent application WO2004/024779.

Among these polymers, we can cite more particularly the products of the polymerization of a mixture of monomers comprising:

- a di(C1-C4 alkyl)amino(C1-C6 alkyl)methacrylate,

- one or more C1-C30 alkyl esters of (meth)acrylic acid,

- a polyethoxylated C10-C30 alkyl methacrylate (20-25 moles of ethylene oxide unit),

- a 30/5 polyethylene glycol/polypropylene glycol allyl ether,

- a hydroxy(C2-C6 alkyl) methacrylate, and

- an ethylene glycol dimethacrylate.

Such a polymer is, for example, the compound marketed by the company LUBRIZOL under the name CARBOPOL AQUA CC® and which corresponds to the INCI name Polyacrylate-1 crosspolymer.

Preferably, the cationic polymers capable of being used in the context of the invention are chosen from, alone or as a mixture:

- cyclopolymers of alkyldiallylamine or dialkyldiallylammonium, and in particular homopolymers or copolymers of salts (for example chloride) of dimethyldiallylammonium,

- optionally crosslinked homopolymers or copolymers of methacryloyloxyalkyl(C1-C4) trialkyl(C1-C4)ammonium salts;

- cationic celluloses and galactomannan gums.

We can notably cite polymers with the INCI names: POLYQUATERNIUM-6, POLYQUATERNIUM-7, POLYQUATERNIUM-37, POLYQUATERNIUM-10, GUAR HYDROXYPROPYLTRIMONIUM CHLORIDE, HYDROXYPROPYL GUAR HYDROXYPROPYLTRIMONIUM CHLORIDE, alone or in mixtures.

Even better, the cationic polymers likely to be present in composition A according to the invention are chosen from halides, in particular chlorides, of dimethyldiallylammonium (Polyquaternium-6).

Preferably, composition A according to the invention comprises one or more cationic polymers, preferentially chosen from halides, in particular chlorides, of dimethyldiallylammonium (Polyquaternium-6).

Composition A used in step (i) according to the invention may comprise the cationic polymer(s) in a total amount of between 0.01 and 8% by weight, in particular from 0.05 to 5% by weight, preferably from 0.1 to 3% by weight, even better from 0.5 to 2% by weight, relative to the total weight of the composition.

In particular, composition A used in step (i) according to the invention may comprise the cationic polymer(s) chosen from, alone or as a mixture:

- cyclopolymers of alkyldiallylamine or dialkyldiallylammonium, and in particular homopolymers or copolymers of salts (for example chloride) of dimethyldiallylammonium,

- optionally crosslinked homopolymers or copolymers of methacryloyloxyalkyl(C1-C4)trialkyl(C1-C4)ammonium salts;

- quaternary polymers of vinylpyrrolidone and vinylimidazole.

in a total amount of between 0.01 and 8% by weight, in particular from 0.05 to 5% by weight, preferably from 0.1 to 3% by weight, even better from 0.5 to 2% by weight, relative to the total weight of the composition.

3/ Amino acid type compounds

Advantageously, composition A used in the context of step (i) according to the present invention may comprise one or more amino acid type compounds.

For the purposes of the present invention, the term “amino acid compound” means an organic compound comprising one or more carboxylic acid and/or sulfonic acid functions, and one or more amine functions, the amine function(s) possibly being intracyclic, optionally in salt form; said amine function(s) being primary or secondary amine functions.

Preferably, the amino acid compound(s) are chosen from amino acid compounds comprising only one or more carboxylic acid functions (therefore not comprising a sulfonic acid function) and/or their salts. Said compounds are also called carboxylic amino acid compounds and are particularly preferred.

Preferably, composition A comprises one or more amino acid type compounds chosen from the compounds corresponding to formula (I) below and/or their salts.

Amino acid type compounds can therefore correspond to the formula (II):

in which p is an integer equal to 1 or 2, it being understood that:

- when p = 1, R forms with the nitrogen atom a saturated heterocycle comprising from 5 to 8 members, preferably 5 members, this cycle possibly being substituted by one or more groups chosen from hydroxyl or (C1-C4)alkyl;

- when p = 2, R represents a hydrogen atom or a (C1-C12)alkyl group, preferably (C1-C4)alkyl, linear or branched, saturated, optionally interrupted by one or more heteroatoms or groups chosen from –S–, –NH– or –C(NH)– and/or optionally substituted by one or more groups chosen from hydroxyl (OH), amino (NH2), -SH, -COOH, -CONH2, –NH–C(NH)–NH2 or a C5-C7 aryl group, in particular phenyl, itself optionally substituted by one or more OH.

Preferably, when p = 1, R forms with the nitrogen atom a saturated heterocycle comprising 5 members, this cycle not being substituted.

Preferably, p=2.

Preferably, when p = 2, R represents a hydrogen atom or a (C1-C4)alkyl group, linear or branched, saturated, optionally interrupted by a heteroatom –S– and/or optionally substituted by one or two groups chosen from hydroxyl, amino or –NH–C(NH)–NH2.

Preferably, p=2 and R represents a hydrogen atom.

Amino acid type compounds may also be a salt of a compound of formula (II).

These salts include salts with organic or mineral bases, for example alkali metal salts, such as lithium, sodium, potassium salts; alkaline earth metal salts such as magnesium, calcium and zinc salts.

The amino acid compounds may be in the form of an optical isomer of L, D or DL configuration, preferably of L configuration.

Examples of compounds according to the present invention in the form of an optical isomer of L configuration include L-methionine, L-serine, L-arginine and L-lysine.

Preferably, the amino acid compound(s) according to the invention are chosen from glycine, arginine, tyrosine, methionine, serine, glutamic acid, lysine, their salts (in particular of alkali or alkaline-earth metals, or of zinc) and their mixtures.

Preferably, the amino acid compound(s) according to the invention are chosen from glycine, arginine, tyrosine, glutamic acid, serine, their salts and their mixtures.

Even better, the amino acid compound is chosen from glycine, its salts (particularly of alkali or alkaline-earth metals, or of zinc) and their mixtures.

As glycine salts according to the present invention, mention may be made of sodium glycinate, zinc glycinate, calcium glycinate, magnesium glycinate, manganese glycinate and potassium glycinate, preferably sodium glycinate and potassium glycinate.

Preferably, the amino acid compound is glycine.

According to a preferred embodiment of the invention, composition A may comprise at least 2 different amino acid type compounds, better still at least 3 different amino acid type compounds.

In particular, composition A according to the invention may comprise at least 2 compounds corresponding to formula (II) and/or their different salts, better still at least 3 compounds corresponding to formula (II) and/or their different salts.

Preferably, composition A according to the invention may comprise at least 2 different compounds chosen from glycine, arginine, tyrosine, glutamic acid, serine, their salts and their mixtures; better still at least 3 different compounds chosen from glycine, arginine, tyrosine, glutamic acid, serine, their salts and their mixtures.

Even better, composition A according to the invention can comprise:

- glycine and/or one of its salts, and

- glutamic acid and/or one of its salts,

- optionally arginine and/or one of its salts,

- optionally serine and/or one of its salts.

Very preferably, the composition according to the invention may comprise glycine and/or one of its salts, glutamic acid and/or one of its salts, arginine and/or one of its salts, and serine and/or one of its salts.

Preferably, the total content of amino acid type compound(s) present in composition A according to the invention is at least 0.5% by weight relative to the total weight of the composition. This content may range from 0.5 to 10% by weight, in particular from 0.8 to 8% by weight, better still from 1 to 7% by weight, even better still from 1.3 to 5% by weight, relative to the total weight of the composition.

In particular, the total content of amino acid compound(s) of formula (II) in composition A according to the invention is at least 0.5% by weight relative to the total weight of the composition. This content may range from 0.5 to 10% by weight, in particular from 0.8 to 8% by weight, better still from 1 to 7% by weight, even better still from 1.3 to 5% by weight, relative to the total weight of the composition.

Better still, the total content of amino acid compound(s) chosen from glycine, serine, glutamic acid, arginine, tyrosine, their salts and their mixtures, in the composition according to the invention is at least 0.5% by weight relative to the total weight of the composition. This content can range from 0.5 to 10% by weight, in particular from 0.8 to 8% by weight, better still from 1 to 7% by weight, even better still from 1.3 to 5% by weight, relative to the total weight of the composition.

In particular, the total content of amino acid type compound(s) chosen from glycine, its salts and their mixtures, in the composition according to the invention is at least 0.5% by weight relative to the total weight of the composition. This content can range from 0.5 to 10% by weight, in particular from 0.7 to 8% by weight, better still from 0.8 to 5% by weight, relative to the total weight of the composition.

4/ Hydroxy(poly)carboxylic acids

The composition according to the invention may also comprise one or more hydroxylated (poly)carboxylic acids, comprising 2 to 8 carbon atoms, and/or their salts.

These (polya)cides are different from the amino acid type compounds previously described.

Preferably, composition A according to the invention comprises one or more hydroxylated (po-ly)carboxylic acids, comprising 2 to 8 carbon atoms, and/or their salts.

Said hydroxylated (poly)carboxylic acids may comprise several, in particular at least 2 COOH groups (in acid or salified form), better still 2 or 3 COOH groups (in acid or salified form). We then speak of hydroxylated polycarboxylic acids.

Said (poly)acids can also comprise a single COOH group; we then speak of hydroxylated monocarboxylic acids.

The (poly)acids according to the invention include mono- and poly-acids.

The hydroxylated (poly)carboxylic acids according to the invention also comprise at least one OH group, but may comprise several, in particular 2 to 3 OH groups.

Preferably, said hydroxylated (poly)carboxylic acids comprise a total of 4 to 6 carbon atoms.

The hydrocarbon chain of said hydroxylated (poly)carboxylic acids may be linear or branched, saturated or unsaturated, and is preferably saturated and linear.

Salts of (poly)acids include salts with organic or inorganic bases, for example alkali metal salts, such as lithium, sodium, potassium salts; alkaline earth metal salts such as magnesium, calcium and zinc salts. Alkali or alkaline earth metal salts are preferred, and in particular sodium salts.

Advantageously, the hydroxylated polycarboxylic acids and/or their salts comprise in total 4 to 6 carbon atoms, 1 to 3 OH groups and 2 to 3 COOH groups (in acid or salified form).

Preferably, the hydroxylated polycarboxylic acids or their salts are chosen from tartaric or citric acids, and their salts, in particular of alkali or alkaline-earth metals; very particularly sodium citrate and/or sodium tartrate; even better citric acid or its salts, in particular of alkali or alkaline-earth metals such as sodium citrate.

Advantageously, the hydroxylated monocarboxylic acids and/or their salts comprise in total 4 to 6 carbon atoms of 1 to 3 OH groups and 1 COOH group (in acid or salified form), and their hydrocarbon chain is saturated and linear.

Preferably, the hydroxylated monocarboxylic acids or their salts are chosen from alpha hydroxy acids and their salts, and in particular from lactic or glycolic acids, and their salts, in particular of alkali or alkaline earth metals.

Preferably, composition A according to the invention comprises one or more hydroxylated polycarboxylic acids comprising in total 2 to 8 carbon atoms, and/or their salts; preferentially chosen from tartaric or citric acids, and their salts, in particular of alkali or alkaline-earth metals such as sodium citrate and/or sodium tartrate; even better chosen from citric acid, sodium citrate and their mixtures.

Preferably, the total content of hydroxylated (poly)carboxylic acids comprising in total 2 to 8 carbon atoms, and/or their salts, present in composition A according to the invention is at least 0.5% by weight, in particular at least 1% by weight, relative to the total weight of the composition. This content may preferably range from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition.

In particular, the total content of hydroxylated polycarboxylic acids comprising in total from 4 to 6 carbon atoms, from 1 to 3 OH groups and 2 or 3 COOH groups, or their salts, present in the composition according to the invention can range from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition.

In particular, the total content of hydroxylated polycarboxylic acids chosen from tartaric or citric acids, and their salts, in particular of alkali or alkaline-earth metals, in the composition according to the invention can range from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition.

Even better, the content of citric acid and/or its salts in the composition according to the invention can range from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition.

5/ Other ingredients

Composition A may comprise a cosmetically acceptable medium, that is to say a medium compatible with topical application to keratin fibers, in particular hair.

Composition A according to the invention may comprise water or a mixture of water and one or more cosmetically acceptable solvents chosen from C ₁ -C ₄ alcohols, such as ethanol, isopropanol, tert-butanol or n-butanol; polyols such as glycerol, propylene glycol, hexylene glycol, and polyethylene glycols; and mixtures thereof.

Preferably, composition A according to the invention comprises a total water content of between 50 and 98%, preferably between 60 and 95% by weight, even better between 65 and 90% by weight, or even between 70 and 85% by weight, relative to the total weight of the composition.

The pH of composition A according to the invention generally varies from 3 to 8, preferably from 3.5 to 7, and better still from 4 to 6, or even from 4.5 to 5.5.

Cosmetic composition A may further comprise at least one usual cosmetic ingredient, notably chosen from vegetable, mineral, animal or synthetic oils; liquid fatty alcohols; liquid fatty esters; solid fatty substances and notably waxes, solid fatty esters, solid alcohols; anionic, cationic, amphoteric and non-ionic surfactants; sunscreens; moisturizing agents; anti-dandruff agents, antioxidant agents; pearlescent and opacifying agents; plasticizing or coalescing agents; preservatives; sequestering agents (EDTA and its salts); coloring matters. Advantageously, it further comprises at least one non-ionic surfactant. The composition may of course comprise several cosmetic ingredients appearing in the list above. The person skilled in the art will take care to choose the ingredients included in the composition, as well as their quantities, in such a way that the advantageous properties of the composition according to the invention are not, or not substantially, altered by the envisaged addition.

B/ Washing step (ii)

The cosmetic treatment process, in particular hair treatment, according to the invention also comprises a step (ii) called washing of said keratin fibers, comprising the application of a cosmetic washing composition B comprising one or more anionic surfactants and/or one or more amphoteric surfactants.

1/ Anionic surfactants

Cosmetic washing composition B may comprise one or more anionic surfactants.

Anionic surfactant means a surfactant containing only anionic groups as ionic or ionizable groups.

In the present description, an entity is described as being "anionic" when it has at least one permanent negative charge or when it can be ionized into a negatively charged entity, under the conditions of use of the composition of the invention (medium, pH for example) and not comprising a cationic charge.

Anionic surfactants can be sulfate, sulfonate and/or carboxylic (or carboxylate) surfactants. A mixture of these surfactants can of course be used.

It is understood in this description that:

- the carboxylate anionic surfactants comprise at least one carboxylic or carboxylate function (-COOH or -COO ^- ), and may optionally also comprise one or more sulfate and/or sulfonate functions;

- the anionic sulfonate surfactants comprise at least one sulfonate function (-SO ₃ H or -SO ₃ ^– ), and may optionally further comprise one or more sulfate functions, but do not comprise a carboxylate function; and

- anionic sulfate surfactants comprise at least one sulfate function but do not comprise a carboxylate or sulfonate function.

The carboxylic anionic surfactants that can be used therefore comprise at least one carboxylic or carboxylate function (-COOH or -COO ^- ).

They may be chosen from the following compounds: acylglycinates, acyllactylates, acylsarcosinates, acylglutamates; alkyl ether carboxylic acids, alkyl (C6-30 aryl) ether carboxylic acids, alkyl-D-galactoside-uronic acids, alkylamido ether carboxylic acids; as well as the salts of these compounds; the alkyl and/or acyl groups of these compounds comprising from 6 to 30 carbon atoms, in particular from 12 to 28, even better from 14 to 24, or even from 16 to 22 carbon atoms; the aryl group preferably denoting a phenyl or benzyl group; these compounds may be polyoxyalkylenated, in particular polyoxyethylenated and then preferably comprising from 1 to 50 ethylene oxide units, better still from 2 to 10 ethylene oxide units.

Also useful are C6-C24 alkyl monoesters of polyglycoside polycarboxylic acids such as C6-C24 alkyl polyglycoside citrates, C6-C24 alkyl polyglycoside tartrates and C6-C24 alkyl polyglycoside sulfosuccinates, and their salts.

Among the above carboxylic surfactants, mention may be made in particular of polyoxyalkylenated alkyl(amido)ether carboxylic acids and their salts, in particular those comprising from 2 to 50 alkylene oxide groups, in particular ethylene oxide, such as the compounds offered by the company KAO under the names AKYPO,

The polyoxyalkylenated alkyl(amido)ether carboxylic acids that can be used are preferably chosen from those of formula (1):

R _1' –(OC ₂ H ₄ ) _n' –OCH ₂ COOA (1)

in which:

- R _1' represents a linear or branched C6-C24 alkyl or alkenyl radical, a (C8-C9)alkylphenyl radical, a radical R _2' CONH-CH2-CH2- with R _2' denoting a linear or branched C9-C21 alkyl or alkenyl radical; preferably R _1' is a C8-C20, preferably C8-C18, alkyl radical;

- n’ is an integer or decimal number (average value) ranging from 2 to 24, preferably from 2 to 10,

- A denotes H, ammonium, Na, K, Li, Mg or a monoethanolamine or triethanolamine residue.

Mixtures of compounds of formula (1) may also be used, in particular mixtures of compounds having different R _1' groups.

Particularly preferred polyoxyalkylenated alkyl(amido)ether carboxylic acids are those of formula (1) in which:

- R _1' denotes a linear or branched C8-C22 alkyl radical, in particular C10-C16, or even C12-C14, or an alkyl(C8-C9)phenyl radical;

- A denotes a hydrogen or sodium atom, and

- n’ varies from 2 to 20, preferably from 2 to 10.

Even more preferably, compounds of formula (1) are used in which R _1' denotes a C12-C14 alkyl, cocoyl, oleyl, nonylphenyl or octylphenyl radical, A denotes a hydrogen or sodium atom and n' varies from 2 to 10.

Among the commercial products, it is preferable to use the products sold by the KAO company under the names:

AKYPO® NP 70 (R ₁ = nonylphenyl, n=7, A=H)

AKYPO® NP 40 (R ₁ = nonylphenyl, n=4, A=H)

AKYPO®OP 40 (R ₁ = octylphenyl, n=4, A=H)

AKYPO® OP 80 (R ₁ = octylphenyl, n=8, A=H)

AKYPO® OP 190 (R ₁ = octylphenyl, n=19, A=H)

AKYPO® RLM 38 (R ₁ =C ₁₂ -C ₁₄ alkyl, n=4, A=H)

AKYPO® RLM 38 NV (R ₁ = C ₁₂ -C ₁₄ alkyl, n=4, A=Na)

AKYPO® RLM 45 CA (R ₁ = C ₁₂ -C ₁₄ alkyl, n=4.5, A=H)

AKYPO® RLM 45 NV (R ₁ = C ₁₂ -C ₁₄ alkyl, n=4.5, A=Na)

AKYPO® RLM 100 (R ₁ = C ₁₂ -C ₁₄ alkyl, n=10, A=H)

AKYPO® RLM 100 NV (R ₁ = C ₁₂ -C ₁₄ alkyl, n=10, A=Na)

AKYPO® RLM 130 (R ₁ = C ₁₂ -C ₁₄ alkyl, n=13, A=H)

AKYPO® RLM 160 NV (R ₁ = C ₁₂ -C ₁₄ alkyl, n=16, A=Na),

or by the SANDOZ company under the names:

SANDOPAN DTC-Acid (R ₁ = C ₁₃ alkyl, n=6, A=H)

SANDOPAN DTC (R ₁ = C ₁₃ alkyl, n=6, A=Na)

SANDOPAN LS 24 (R ₁ = C ₁₂ -C ₁₄ alkyl, n=12, A=Na)

SANDOPAN JA 36 (R ₁ = C ₁₃ alkyl, n=18, A=H),

and more particularly, the products sold under the following names:

AKYPO® RLM 45 (INCI: Laureth-5 carboxylic acid)

AKYPO®RLM 100

AKYPO® RLM 38.

Preferably, the carboxylic anionic surfactants are chosen from, alone or as a mixture:

- acylglutamates, particularly C6-C24, or even C12-C20, such as stearoylglutamates, and in particular disodium stearoylglutamate;

- acylsarcosinates, particularly C6-C24, or even C12-C20, such as palmitoylsarcosinates, and in particular sodium palmitoylsarcosinate;

- acyllactylates, particularly C12-C28, or even C14-C24, such as behenoyllactylates, and in particular sodium behenoyllactylate;

- C6-C24 acylglycinates, especially C12-C20;

- alkyl(C6-C24)ethercarboxylates, and in particular alkyl(C12-C20)ethercarboxylates; in particular those comprising from 2 to 50 ethylene oxide groups;

- polyoxyalkylenated alkyl(C6-C24)amidoether carboxylic acids, in particular those containing 2 to 50 ethylene oxide groups;

in particular in acid form or as salts of alkali or alkaline earth metals, ammonium or amino alcohol.

Preferably, the composition comprises one or more acylsarcosinates, in particular C6-C24, or even C12-C20, such as palmitoylsarcosinates and lauroylsarcosinates, as well as their salts; and in particular sodium palmitoylsarcosinate and/or sodium lauroylsarcosinate.

The anionic sulfonate surfactants that may be used comprise at least one sulfonate function (-SO ₃ H or -SO ₃ ^– ). They may be chosen from the following compounds: alkylsulfonates, alkylethersulfonates, alkylamidesulfonates, alkylarylsulfonates, alpha-olefinsulfonates, paraffinsulfonates, alkylsulfosuccinates, alkylethersulfosuccinates, alkylamidesulfosuccinates, alkylsulfoacetates, N-acyltaurates, acylisethionates; alkylsulfolaurates; as well as the salts of these compounds;

the alkyl groups of these compounds containing from 6 to 30 carbon atoms, in particular from 12 to 28, even better from 14 to 24, or even from 16 to 22, carbon atoms; the aryl group preferably denoting a phenyl or benzyl group;

these compounds may be polyoxyalkylenated, in particular polyoxyethylenated and then preferably comprising from 1 to 50 ethylene oxide units, better still from 2 to 10 ethylene oxide units.

Preferably, the anionic sulfonate surfactants are chosen from, alone or in a mixture:

- C6-C24 olefinsulfonates, especially C12-C20,

- C6-C24 alkylsulfosuccinates, especially C12-C20, especially laurylsulfosuccinates.

- C6-C24 alkyl ether sulfosuccinates, in particular C12-C20;

- (C6-C24)acylisethionates, preferably (C12-C18)acylisethionates,

- C6-C24 alkylsulfoacetates, especially C12-C20,

in particular in the form of salts of alkali or alkaline earth metals, ammonium, or amino alcohol.

The anionic sulfate surfactants that can be used contain at least one sulfate function (-OSO ₃ H or -OSO ₃ ^- ).

They can be chosen from the following compounds: alkyl sulfates, alkyl ether sulfates, alkylamido ether sulfates, alkylaryl polyether sulfates, monoglyceride sulfates; as well as the salts of these compounds;

the alkyl groups of these compounds comprising from 6 to 30 carbon atoms, in particular from 12 to 28, even better from 14 to 24, or even from 16 to 22, carbon atoms; the aryl group preferably denoting a phenyl or benzyl group;

these compounds may be polyoxyalkylenated, in particular polyoxyethylenated and then preferably comprising from 1 to 50 ethylene oxide units, better still from 2 to 10 ethylene oxide units.

Preferably, the anionic sulfate surfactants are chosen from, alone or in a mixture:

- alkyl sulfates, particularly C6-C24, or even C12-C20, and

- alkyl ether sulfates, in particular C6-C24, or even C12-C20, preferably comprising from 2 to 20 ethylene oxide units;

in particular in the form of salts of alkali or alkaline earth metals, ammonium, or amino alcohol.

When the anionic surfactant is in salt form, said salt may be chosen from alkali metal salts such as the sodium or potassium salt, ammonium salts, amine salts and in particular amino alcohol salts, and alkaline earth metal salts such as the magnesium salt.

Examples of amino alcohol salts include mono-, di- and triethanolamine salts, mono-, di- or tri-isopropanolamine salts, 2-amino 2-methyl 1-propanol, 2-amino 2-methyl 1,3-propanediol and tris(hydroxymethyl)amino methane salts.

Preferably, salts of alkali or alkaline earth metals are used, and in particular sodium or magnesium salts.

Preferably, the anionic surfactants are chosen from, alone or as a mixture,

- C6-C24 alkyl sulfates, especially C12-C20,

- C6-C24, especially C12-C20, alkyl ether sulfates; preferably comprising from 2 to 20 ethylene oxide units;

- C6-C24 alkylsulfosuccinates, in particular C12-C20, in particular laurylsulfosuccinates;

- C6-C24 olefinsulfonates, especially C12-C20,

- C6-C24 alkyl ether sulfosuccinates, in particular C12-C20;

- (C6-C24)acylisethionates, preferably (C12-C18)acylisethionates,

- C6-C24 acylsarcosinates, in particular C12-C20; in particular palmitoylsarcosinates and lauroylsarcosinates;

- alkyl(C6-C24)ethercarboxylates, preferably alkyl(C12-C20)ethercarboxylates; in particular those comprising from 2 to 50 ethylene oxide groups;

- polyoxyalkylenated alkyl(C6-C24)amidoethercarboxylic acids and their salts, in particular those containing from 2 to 50 alkylene oxide groups, in particular ethylene;

- C6-C24 acylglutamates, especially C12-C20;

- C6-C24 acylglycinates, especially C12-C20;

- C6-C24 alkylsulfoacetates, especially C12-C20,

in particular in acid form or as salts of alkali or alkaline earth metals, ammonium, or amino alcohol.

Preferably, composition B comprises one or more anionic sulfonate and/or carboxylic (or carboxylate) surfactants, preferably chosen from C6-C24, in particular C12-C2, alkyl ether sulfosuccinates, (C6-C24)acylisethionates, preferably (C12-C18)acylisethionates, C6-C24, in particular C12-C20 acyl sarcosinates, C6-C24, in particular C12-C20 alkyl sulfoacetates, and mixtures thereof, as well as their salts; particularly in the form of alkali or alkaline earth metal, ammonium, or amino alcohol salts.

Preferably, composition B does not comprise anionic sulfate surfactant (0%).

The anionic surfactant(s) are preferably present in the washing composition B according to the invention in a total amount ranging from 2 to 40% by weight, in particular from 5 to 35% by weight, better still from 10 to 30% by weight, even better still from 15 to 25% by weight, relative to the total weight of the composition.

The anionic surfactant(s) chosen from sulfonate and/or carboxylic (or carboxylate) surfactants are preferably present in the washing composition B according to the invention in a total amount ranging from 2 to 40% by weight, in particular from 5 to 35% by weight, better still from 10 to 30% by weight, even better still from 15 to 25% by weight, relative to the total weight of the composition.

2/ Amphoteric surfactants

Washing composition B may also comprise one or more amphoteric surfactants. By amphoteric surfactant is meant amphoteric or zwitterionic surfactant.

In particular, the amphoteric surfactant(s) are non-silicone. They may in particular be derivatives of secondary or tertiary aliphatic amines, optionally quaternized, in which the aliphatic group is a linear or branched chain comprising from 8 to 22 carbon atoms, said amine derivatives containing at least one anionic group such as, for example, a carboxylate, sulfonate, sulfate, phosphate or phosphonate group.

In particular, mention may be made of alkyl( _C8 - _C20 )betaines, alkyl( _C8 - _C20 )sulfobetaines, alkyl( _C8 - _C20 )amidoalkyl( _C3 - _C8 )betaines and alkyl( _C8 - _C20 )amidalkyl( _C6 - _C8 )sulfobetaines.

Among the derivatives of secondary or tertiary aliphatic amines, optionally quaternized, which can be used, as defined above, we may also cite the compounds of the following respective structures (II) and (III):

R _a -CONHCH ₂ CH ₂ -N ⁺ (R _b )(R _c )-CH ₂ COO ^- , M ⁺ , X ^- (II)

in which:

- R _a represents a C ₁₀ to C ₃₀ alkyl or alkenyl group derived from an acid R _a COOH, preferably present in hydrolyzed coconut oil, a heptyl, nonyl or undecyl group;

- R _b represents a beta-hydroxyethyl group; and

- R _c represents a carboxymethyl group;

- M ⁺ represents a cationic counterion from an alkali, alkaline earth metal, such as sodium, an ammonium ion or an ion from an organic amine, and

- X ^- represents an organic or inorganic anionic counterion, such as that chosen from halides, acetates, phosphates, nitrates, alkyl(C ₁ -C ₄ )sulfates, alkyl(C ₁ -C ₄ )- or alkyl(C ₁ -C ₄ )aryl-sulfonates, in particular methylsulfate and ethylsulfate; or else M ⁺ and X ^- are absent;

R _a' -CONHCH ₂ CH ₂ -N(B)(B') (III)

years in which:

- B represents the group -CH ₂ CH ₂ OX';

- B' represents the group -(CH ₂ ) _z Y', with z = 1 or 2;

- X' represents the group -CH ₂ COOH, -CH ₂ -COOZ', -CH ₂ CH ₂ COOH, CH ₂ CH ₂ -COOZ', or a hydrogen atom;

- Y' represents the group –COOH, -COOZ', -CH ₂ CH(OH)SO ₃ H or the group CH ₂ CH(OH)SO ₃ -Z';

- Z’ represents a cationic counterion derived from an alkali or alkaline earth metal, such as sodium, an ammonium ion or an ion derived from an organic amine;

- R _a' represents a C ₁₀ to C ₃₀ alkyl or alkenyl group of an acid R _a' -COOH preferably present in coconut oil or in hydrolyzed linseed oil, an alkyl group, in particular C ₁₇ and its iso form, an unsaturated C ₁₇ group.

These compounds are classified in the CTFA dictionary, 5th edition, 1993, under the names disodium cocoamphodiacetate, disodium lauroamphodiacetate, disodium caprylamphodiacetate, disodium capryloamphodiacetate, disodium cocoamphodipropionate, disodium lauroamphodipropionate, disodium caprylamphodipropionate, disodium capryloamphodipropionate, lauroamphodipropionic acid, cocoamphodipropionic acid.

For example, we can cite cocoamphodiacetate marketed by the company RHODIA under the trade name MIRANOL® C2M concentrate.

Compounds of formula (IV) can also be used:

R _a'' -NHCH(Y'')-(CH ₂ ) _n CONH(CH ₂ ) _n' -N(R _d )(R _e ) (IV)

in which:

- Y'' represents the group –COOH, -COOZ'', -CH ₂ -CH(OH)SO ₃ H or the group CH ₂ CH(OH)SO ₃ -Z'';

- R _d and R _e , independently of one another, represent a C ₁ to C ₄ alkyl or hydroxyalkyl radical;

- Z’’ represents a cationic counterion derived from an alkali or alkaline earth metal, such as sodium, an ammonium ion or an ion derived from an organic amine;

- R _a'' represents a C ₁₀ to C ₃₀ alkyl or alkenyl group of an acid R _a'' -COOH preferably present in coconut oil or in hydrolyzed linseed oil;

- n and n’, independently of each other, denote an integer ranging from 1 to 3.

Among the compounds of formula (II) we can cite the compound classified in the CTFA dictionary under the name sodium diethylaminopropyl cocoaspartamide and marketed by the company CHIMEX under the name CHIMEXANE HB.

These compounds can be used alone or in mixtures.

Among the amphoteric surfactants, preferably used are alkyl( _C8 - _C20 )betaines such as cocobetaine, alkyl( _C8 - _C20 )amidoalkyl( _C3 - _C8 )betaines such as cocamidopropylbetaine, and mixtures thereof, and compounds of formula (IV) such as the sodium salt of diethylaminopropyl lauryl amino succinamate (INCI name: sodium diethylaminopropyl cocoaspartamide).

Preferably, the amphoteric surfactants are chosen from alkyl(C8-C20)betaines such as cocobetaine, alkyl(C8-C20)amidoalkyl(C3-C8)betaines such as cocamidopropylbetaine and mixtures thereof; better still from alkyl( _C8 - _C20 )amidoalkyl( _C3 - _C8 )betaines such as cocamidopropylbetaine.

Preferably, the amphoteric surfactant(s) are present in composition B at a total content ranging from 0.1 to 20% by weight, preferably in a content ranging from 0.5 to 10% by weight, even better from 1 to 5% by weight, relative to the total weight of composition B.

Preferably, the amphoteric surfactant(s) chosen from alkyl(C ₈ -C ₂₀ )betaines such as cocobetaine, alkyl(C ₈ -C ₂₀ )amidoalkyl(C ₃ -C ₈ )betaines such as cocamidopropylbetaine and mixtures thereof are present in composition B at a total content ranging from 0.1 to 20% by weight, preferably in a content ranging from 0.5 to 10% by weight, even better from 1 to 5% by weight, relative to the total weight of composition B.

Preferably, composition B used in step (ii) of the process according to the invention comprises one or more anionic surfactants and one or more amphoteric surfactants.

3/ Non-ionic surfactants

Cosmetic composition B may optionally comprise one or more non-ionic surfactants, in particular such as those described in “Handbook of Surfactants” by M.R. PORTER, Blackie & Son editions (Glasgow and London), 1991, pp 116-178.

Examples of non-ionic surfactants include the following compounds, alone or in mixtures:

- oxyalkylenated alkyl(C ₈ -C ₂₄ )phenols;

- _C8 to _C40 alcohols, saturated or unsaturated, linear or branched, oxyalkylenated or glycerolated, they preferably comprise one or two fatty chains;

- _C8 to _C30 fatty acid amides, saturated or unsaturated, linear or branched, oxyalkylenated;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of polyethylene glycols;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of sorbitol, preferably oxyethylenated;

- esters of fatty acids and sucrose,

- alkyl(C ₈ -C ₃₀ )(poly)glucosides, alkenyl(C ₈ -C ₃₀ )(poly)glucosides, optionally oxyalkylenated and comprising from 1 to 15 glucose units, alkyl(C ₈ -C ₃₀ )(poly)glucoside esters,

- oxyethylenated vegetable oils, saturated or not;

- ethylene oxide and/or propylene oxide condensates;

- N-alkyl( _C8 - _C30 )glucamine and N-acyl( _C8 - _C30 )methylglucamine derivatives;

- amine oxides.

The oxyalkylenated units are more particularly oxyethylenated, oxypropylenated units, or their combination, preferably oxyethylenated.

The number of moles of ethylene and/or propylene oxide preferably ranges from 1 to 250, more particularly from 2 to 100; better still from 2 to 50; the number of moles of glycerol ranges in particular from 1 to 50, better still from 1 to 10.

Advantageously, the non-ionic surfactants according to the invention do not comprise oxypropylenated units.

Preferably, they comprise a number of moles of ethylene oxide ranging from 1 to 250, in particular from 2 to 100, better still from 2 to 50.

As an example of glycerolated nonionic surfactants, _C8 to _C40 alcohols, mono- or polyglycerolated, comprising from 1 to 50 moles of glycerol, preferably from 1 to 10 moles of glycerol, are preferably used.

Examples of compounds of this type include lauryl alcohol containing 4 moles of glycerol (INCI name: POLYGLYCERYL-4 LAURYL ETHER), lauryl alcohol containing 1.5 moles of glycerol, oleyl alcohol containing 4 moles of glycerol (INCI name: POLYGLYCERYL-4 OLEYL ETHER), oleyl alcohol containing 2 moles of glycerol (INCI name: POLYGLYCERYL-2 OLEYL ETHER), cetearyl alcohol containing 2 moles of glycerol, cetearyl alcohol containing 6 moles of glycerol, oleocetyl alcohol containing 6 moles of glycerol, and octadecanol containing 6 moles of glycerol.

Among the glycerolated alcohols, it is more particularly preferred to use C ₈ to C ₁₀ alcohol with one mole of glycerol, C ₁₀ to C ₁₂ alcohol with one mole of glycerol and C ₁₂ alcohol with 1.5 moles of glycerol.

The non-ionic surfactant(s) capable of being used in the washing composition according to the invention are preferably chosen from, alone or as a mixture:

- _C8 to _C40 alcohols, saturated or unsaturated, linear or branched, oxyethylenated comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50, more particularly from 2 to 40 moles of ethylene oxide; they preferably comprise one or two fatty chains;

- oxyethylenated vegetable oils, saturated or not, comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50;

- alkyl(C ₈ -C ₃₀ ) (poly)glucosides, optionally oxyalkylenated, preferably from 0 to 10 moles of ethylene oxide, and comprising 1 to 15 glucose units;

- _C8 to _C40 alcohols, mono- or polyglycerolated, comprising from 1 to 50 moles of glycerol, preferably from 1 to 10 moles of glycerol;

- amides of _C8 to _C30 fatty acids, saturated or unsaturated, linear or branched, oxyalkylenated;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of polyethylene glycols;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of sorbitol, preferably oxyethylenated.

More preferably, the non-ionic surfactant(s) are chosen from, alone or as a mixture:

- _C8 to _C40 alcohols, saturated or unsaturated, linear or branched, oxyethylenated comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50, more particularly from 2 to 40 moles of ethylene oxide and comprising one or two fatty chains, in particular at least one C8-C20 alkyl chain, in particular C10-C18;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of sorbitol, preferably oxyethylenated, and

- alkyl(C ₈ -C ₃₀ ) (poly)glucosides, optionally oxyalkylenated, preferably comprising from 1 to 10 moles of ethylene oxide, and comprising 1 to 15 glucose units.

In particular, the washing composition B may comprise one or more non-ionic surfactants of alkyl(poly)glycoside type of general formula:

R1O-(R2O)t-(G)v

in which:

- R1 represents a linear or branched alkyl or alkenyl radical containing 6 to 24 carbon atoms, in particular 8 to 18 carbon atoms, or an alkylphenyl radical of which the linear or branched alkyl radical contains 6 to 24 carbon atoms, in particular 8 to 18 carbon atoms; preferably a saturated or unsaturated, linear or branched alkyl radical containing from 8 to 18 carbon atoms;

- R2 represents an alkylene radical containing 2 to 4 carbon atoms,

- G represents a sugar unit comprising 5 to 6 carbon atoms; preferably glucose, fructose or galactose; even better glucose;

- t denotes a value ranging from 0 to 10, preferably from 0 to 4, better from 0 to 3, even better 0;

- v denotes a value ranging from 1 to 15, preferably from 1 to 4; the average degree of polymerization (v) being more particularly between 1 and 2.

The glucosidic bonds between the sugar units are generally of the 1-6 or 1-4 type, preferably of the 1-4 type.

Preferably, the alkyl(poly)glycoside surfactant is an alkyl(poly)glucoside surfactant.

Preferably, the washing composition B comprises the non-ionic surfactant(s), when present, in a total content ranging from 0.05 to 15% by weight, preferably from 0.1 to 10% by weight, preferentially from 0.2 to 5% by weight, relative to the total weight of the washing composition.

4/ Other ingredients

Washing composition B may comprise water or a mixture of water and one or more cosmetically acceptable solvents chosen from C ₁ -C ₄ alcohols, such as ethanol, isopropanol, tert-butanol or n-butanol; polyols such as glycerol, propylene glycol and polyethylene glycols; and mixtures thereof.

Preferably, the washing composition B according to the invention has a total water content of between 20 and 95% by weight, preferably between 30 and 90%, preferentially between 40 and 85% by weight, even better between 50 and 80% by weight relative to the total weight of the composition.

The pH of the washing composition according to the invention generally varies from 3 to 9, preferably from 3.5 to 7, preferentially from 4 to 6, and better still from 5 to 6.

The cosmetic washing composition according to the invention may also comprise at least one usual cosmetic ingredient, in particular chosen from conditioning agents, polymeric or not; mention may in particular be made of silicones, organomodified or not, such as amino silicones; vegetable, mineral or synthetic oils; liquid fatty alcohols; liquid fatty esters; solid fatty substances and in particular waxes, solid fatty esters, solid alcohols, ceramides; sunscreens; moisturizing agents; anti-dandruff agents, antioxidant agents; pearlescent and opacifying agents; plasticizing or coalescing agents; preservatives; sequestering agents (EDTA and its salts); coloring matters. The composition may of course comprise several cosmetic ingredients appearing in the list above. The person skilled in the art will take care to choose the ingredients included in the composition, as well as their quantities, in such a way that the advantageous properties of the composition according to the invention are not, or not substantially, altered by the envisaged addition.

C/ Step (iii) of application of a composition C

The cosmetic treatment process, in particular hair treatment, according to the invention also comprises a step (iii) of application to said keratin fibres of a cosmetic composition C comprising one or more amino acid type compounds and one or more hydroxylated (poly)carboxylic acids, comprising 2 to 8 carbon atoms, and/or their salts.

1/ Amino acid type compounds

Composition C used in the context of step (iii) according to the present invention comprises one or more amino acid type compounds.

Preferably, composition C comprises one or more amino acid type compounds chosen from the compounds corresponding to formula (I) below and/or their salts.

Amino acid type compounds can therefore correspond to the formula (II):

in which p is an integer equal to 1 or 2, it being understood that:

- when p = 1, R forms with the nitrogen atom a saturated heterocycle comprising from 5 to 8 members, preferably 5 members, this cycle possibly being substituted by one or more groups chosen from hydroxyl or (C1-C4)alkyl;

- when p = 2, R represents a hydrogen atom or a (C1-C12)alkyl group, preferably (C1-C4)alkyl, linear or branched, saturated, optionally interrupted by one or more heteroatoms or groups chosen from –S–, –NH– or –C(NH)– and/or optionally substituted by one or more groups chosen from hydroxyl (OH), amino (NH2), -SH, -COOH, -CONH2, –NH–C(NH)–NH2 or a C5-C7 aryl group, in particular phenyl, itself optionally substituted by one or more OH.

Preferably, when p = 1, R forms with the nitrogen atom a saturated heterocycle comprising 5 members, this cycle not being substituted.

Preferably, p=2.

Preferably, when p = 2, R represents a hydrogen atom or a (C1-C4)alkyl group, linear or branched, saturated, optionally interrupted by a heteroatom –S– and/or optionally substituted by one or two groups chosen from hydroxyl, amino or –NH–C(NH)–NH2.

Preferably, p=2 and R represents a hydrogen atom.

Amino acid type compounds may also be a salt of a compound of formula (II).

These salts include salts with organic or mineral bases, for example alkali metal salts, such as lithium, sodium, potassium salts; alkaline earth metal salts such as magnesium, calcium and zinc salts.

The amino acid compounds may be in the form of an optical isomer of L, D or DL configuration, preferably of L configuration.

Examples of compounds according to the present invention in the form of an optical isomer of L configuration include L-methionine, L-serine, L-arginine and L-lysine.

Preferably, the amino acid compound(s) according to the invention are chosen from glycine, arginine, tyrosine, methionine, serine, glutamic acid, lysine, their salts (in particular of alkali or alkaline-earth metals, or of zinc) and their mixtures.

Preferably, the amino acid compound(s) according to the invention are chosen from glycine, arginine, tyrosine, glutamic acid, serine, their salts and their mixtures.

Even better, the amino acid compound is chosen from glycine, its salts (particularly of alkali or alkaline-earth metals, or of zinc) and their mixtures.

As glycine salts according to the present invention, mention may be made of sodium glycinate, zinc glycinate, calcium glycinate, magnesium glycinate, manganese glycinate and potassium glycinate, preferably sodium glycinate and potassium glycinate.

Preferably, the amino acid compound is glycine.

According to a preferred embodiment of the invention, composition C can comprise at least 2 different amino acid type compounds, better still at least 3 different amino acid type compounds.

In particular, composition C according to the invention may comprise at least 2 compounds corresponding to formula (II) and/or their different salts, better still at least 3 compounds corresponding to formula (II) and/or their different salts.

Preferably, composition C according to the invention may comprise at least 2 different compounds chosen from glycine, arginine, tyrosine, glutamic acid, serine, their salts and their mixtures; better still at least 3 different compounds chosen from glycine, arginine, tyrosine, glutamic acid, serine, their salts and their mixtures.

Even better, composition C according to the invention can comprise:

- glycine and/or one of its salts, and

- glutamic acid and/or one of its salts,

- optionally arginine and/or one of its salts,

- optionally serine and/or one of its salts.

Very preferably, the composition according to the invention may comprise glycine and/or one of its salts, glutamic acid and/or one of its salts, arginine and/or one of its salts, and serine and/or one of its salts.

Preferably, the total content of amino acid compound(s) present in composition C according to the invention is at least 0.5% by weight relative to the total weight of the composition. This content may range from 0.5 to 12% by weight, in particular from 1 to 10% by weight, better still from 2 to 8% by weight, even better still from 3 to 7% by weight, relative to the total weight of the composition.

In particular, the total content of amino acid compound(s) of formula (II) in composition C according to the invention is at least 0.5% by weight relative to the total weight of the composition. This content may range from 0.5 to 12% by weight, in particular from 1 to 10% by weight, better still from 2 to 8% by weight, even better still from 3 to 7% by weight, relative to the total weight of the composition.

Better still, the total content of amino acid compound(s) chosen from glycine, methionine, serine, glutamic acid, arginine, lysine, their salts and their mixtures, in composition C according to the invention is at least 0.5% by weight relative to the total weight of the composition. This content can range from 0.5 to 12% by weight, in particular from 1 to 10% by weight, better still from 2 to 8% by weight, even better still from 3 to 7% by weight, relative to the total weight of the composition.

In particular, the total content of amino acid type compound(s) chosen from glycine, its salts and their mixtures, in composition C according to the invention is at least 0.5% by weight relative to the total weight of the composition. This content can range from 0.5 to 12% by weight, in particular from 1 to 10% by weight, better still from 2 to 8% by weight, even better still from 3 to 7% by weight, relative to the total weight of the composition.

2/ Hydroxy(poly)carboxylic acids

Composition C according to the invention also comprises one or more hydroxylated (poly)carboxylic acids, comprising 2 to 8 carbon atoms, and/or their salts.

These (polya)cides are different from the amino acid type compounds previously described.

Said hydroxylated (poly)carboxylic acids may comprise several, in particular at least 2 COOH groups (in acid or salified form), better still 2 or 3 COOH groups (in acid or salified form). We then speak of hydroxylated polycarboxylic acids.

Said (poly)acids can also comprise a single COOH group; we then speak of hydroxylated monocarboxylic acids.

The (poly)acids according to the invention include mono- and poly-acids.

The hydroxylated (poly)carboxylic acids according to the invention also comprise at least one OH group, but may comprise several, in particular 2 to 3 OH groups.

Preferably, said hydroxylated (poly)carboxylic acids comprise a total of 4 to 6 carbon atoms.

The hydrocarbon chain of said hydroxylated (poly)carboxylic acids may be linear or branched, saturated or unsaturated, and is preferably saturated and linear.

Salts of (poly)acids include salts with organic or inorganic bases, for example alkali metal salts, such as lithium, sodium, potassium salts; alkaline earth metal salts such as magnesium, calcium and zinc salts. Alkali or alkaline earth metal salts are preferred, and in particular sodium salts.

Advantageously, the hydroxylated polycarboxylic acids and/or their salts comprise in total from 4 to 6 carbon atoms, from 1 to 3 OH groups and 2 to 3 COOH groups (in acid or salified form).

Preferably, the hydroxylated polycarboxylic acids or their salts are chosen from tartaric or citric acids, and their salts, in particular of alkali or alkaline-earth metals; very particularly sodium citrate and/or sodium tartrate; even better citric acid or its salts, in particular of alkali or alkaline-earth metals such as sodium citrate.

Advantageously, the hydroxylated monocarboxylic acids and/or their salts comprise in total 4 to 6 carbon atoms of 1 to 3 OH groups and 1 COOH group (in acid or salified form), and their hydrocarbon chain is saturated and linear.

Preferably, the hydroxylated monocarboxylic acids or their salts are chosen from alpha hydroxy acids and their salts, and in particular from lactic or glycolic acids, and their salts, in particular of alkali or alkaline earth metals.

Preferably, composition C according to the invention comprises one or more hydroxylated polycarboxylic acids comprising in total 2 to 8 carbon atoms, and/or their salts; preferentially chosen from tartaric or citric acids, and their salts, in particular of alkali or alkaline-earth metals such as sodium citrate and/or sodium tartrate; even better chosen from citric acid, sodium citrate and their mixtures.

Preferably, the total content of hydroxylated (poly)carboxylic acids comprising in total 2 to 8 carbon atoms, and/or their salts, present in composition C according to the invention is at least 0.5% by weight, in particular at least 1% by weight, relative to the total weight of the composition. This content may preferably range from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition.

In particular, the total content of hydroxylated polycarboxylic acids comprising in total from 4 to 6 carbon atoms, from 1 to 3 OH groups and 2 or 3 COOH groups, or their salts, present in composition C according to the invention can range from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition.

In particular, the total content of hydroxylated polycarboxylic acids chosen from tartaric or citric acids, and their salts, in particular of alkali or alkaline-earth metals, in composition C according to the invention can range from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition.

Even better, the content of citric acid and/or its salts in composition C according to the invention can range from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition.

3/ Polyols

Composition C may advantageously comprise one or more polyols.

The term “polyol” means an organic compound consisting of a hydrocarbon chain optionally interrupted by one or more oxygen atoms and carrying at least two free hydroxyl groups (-OH) preferably carried by different carbon atoms, this compound being able to be cyclic or acyclic, linear or branched, saturated or unsaturated.

More particularly, the polyol(s) comprise from 2 to 30 hydroxy groups, better still from 2 to 10 hydroxy groups, preferentially from 2 to 3 hydroxy groups. Preferably, they comprise from 2 to 10 carbon atoms, in particular from 2 to 8 carbon atoms, better still from 2 to 6 carbon atoms.

Advantageously, the polyol(s) are chosen from diols and/or triols, comprising from 2 to 10 carbon atoms.

Mention may in particular be made of diglycerin, glycerin, propylene glycol, propane-1,3-diol, 1,3-butylene glycol, pentane-1,2-diol, octane-1,2-diol, dipropylene glycol, hexylene glycol, ethylene glycol, polyethylene glycols, sorbitol, sugars such as glucose and mixtures thereof; preferably among glycerin, propylene glycol, propane-1,3-diol, 1,3-butylene glycol, pentane-1,2-diol, octane-1,2-diol, dipropylene glycol, hexylene glycol, ethylene glycol, sorbitol and mixtures thereof; and even better among glycerin, propylene glycol, propane-1,3-diol, and mixtures thereof.

Preferably, the polyol(s) may be present in composition C in a total content ranging from 0.1 to 40% by weight, better still ranging from 1 to 35% by weight, even better still from 5 to 30% by weight, preferentially ranging from 10 to 25% by weight, relative to the total weight of the composition.

Preferably, the polyol(s) chosen from glycerin, propylene glycol, propane-1,3-diol, 1,3-butylene glycol, pentane-1,2-diol, octane-1,2-diol, dipropylene glycol, hexylene glycol, ethylene glycol, sorbitol and mixtures thereof; may be present in composition C in a total content ranging from 0.1 to 40% by weight, better still ranging from 1 to 35% by weight, even better still from 5 to 30% by weight, preferentially ranging from 10 to 25% by weight, relative to the total weight of the composition.

4/ Non-ionic surfactants

Composition C used in the process according to the invention may optionally comprise one or more non-ionic surfactants.

Examples of non-ionic surfactants include the following compounds, alone or in mixtures:

- oxyalkylenated alkyl(C ₈ -C ₂₄ )phenols;

- _C8 to _C40 alcohols, saturated or unsaturated, linear or branched, oxyalkylenated or glycerolated, they preferably comprise one or two fatty chains;

- _C8 to _C30 fatty acid amides, saturated or unsaturated, linear or branched, oxyalkylenated;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of polyethylene glycols;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of sorbitol, preferably oxyethylenated;

- esters of fatty acids and sucrose,

- alkyl(poly)glycosides which are optionally oxyalkylenated (0 to 10 oxyalkylenated units) and which may comprise 1 to 15 glucose units,

- oxyethylenated vegetable oils, saturated or not;

- ethylene oxide and/or propylene oxide condensates;

- N-alkyl( _C8 - _C30 )glucamine and N-acyl( _C8 - _C30 )methylglucamine derivatives;

- amine oxides.

The oxyalkylenated units are more particularly oxyethylenated, oxypropylenated units, or their combination, preferably oxyethylenated.

The number of moles of ethylene and/or propylene oxide preferably ranges from 1 to 250, more particularly from 2 to 100; better still from 2 to 50; the number of moles of glycerol ranges in particular from 1 to 50, better still from 1 to 10.

Advantageously, the non-ionic surfactants according to the invention do not comprise oxypropylenated units.

Preferably, they comprise a number of moles of ethylene oxide ranging from 1 to 250, in particular from 2 to 100, better still from 2 to 50.

As examples of glycerolated nonionic surfactants, _C8 to _C40 alcohols, mono- or polyglycerolated, comprising from 1 to 50 moles of glycerol, preferably from 1 to 10 moles of glycerol, are preferably used.

Examples include lauryl alcohol with 4 moles of glycerol (INCI name: POLYGLYCERYL-4 LAURYL ETHER), lauryl alcohol with 1.5 moles of glycerol, oleyl alcohol with 4 moles of glycerol (INCI name: POLYGLYCERYL-4 OLEYL ETHER), oleyl alcohol with 2 moles of glycerol (INCI name: POLYGLYCERYL-2 OLEYL ETHER), cetearyl alcohol with 2 moles of glycerol, cetearyl alcohol with 6 moles of glycerol, oleocetyl alcohol with 6 moles of glycerol, and octadecanol with 6 moles of glycerol.

Among the glycerolated alcohols, it is more particularly preferred to use C ₈ to C ₁₀ alcohol with one mole of glycerol, C ₁₀ to C ₁₂ alcohol with one mole of glycerol and C ₁₂ alcohol with 1.5 moles of glycerol.

Non-ionic surfactants of the alkyl(poly)glycoside type can in particular be represented by the following general formula: R1O-(R2O)t-(G)v in which:

- R1 represents a linear or branched alkyl or alkenyl radical containing 6 to 24 carbon atoms, in particular 8 to 18 carbon atoms, or an alkylphenyl radical of which the linear or branched alkyl radical contains 6 to 24 carbon atoms, in particular 8 to 18 carbon atoms;

- R2 represents an alkylene radical containing 2 to 4 carbon atoms,

- G represents a sugar unit containing 5 to 6 carbon atoms,

- t denotes a value ranging from 0 to 10, preferably from 0 to 4,

- v denotes a value ranging from 1 to 15, preferably from 1 to 4.

Preferably, the alkyl(poly)glycoside surfactants are compounds of the formula described above in which:

- R1 denotes a saturated or unsaturated, linear or branched alkyl radical containing from 8 to 18 carbon atoms,

- R2 represents an alkylene radical containing 2 to 4 carbon atoms,

- t denotes a value ranging from 0 to 3, preferably equal to 0,

- G denotes glucose, fructose or galactose, preferably glucose;

- the degree of polymerization, that is to say the value of v, which can range from 1 to 15, preferably from 1 to 4; the average degree of polymerization being more particularly between 1 and 2.

The glucosidic bonds between the sugar units are generally of the 1-6 or 1-4 type, preferably of the 1-4 type. Preferably, the alkyl(poly)glycoside surfactant is an alkyl(poly)glucoside surfactant. Particularly preferred are C8/C16 alkyl-1,4-(poly)glucosides, and in particular decylglucosides and caprylyl/capryl glucosides.

Commercial products include products sold by COGNIS under the names PLANTAREN® (600 CS/U, 1200 and 2000) or PLANTACARE® (818, 1200 and 2000); products sold by SEPPIC under the names ORAMIX CG 110 and ORAMIX® NS 10; products sold by BASF under the name LUTENSOL GD 70 or products sold by CHEM Y under the name AG10 LK.

Preferably, C8/C16-(poly)glycoside 1,4 are used, in particular in 53% aqueous solution, such as those marketed by COGNIS under the reference PLANTACARE® 818 UP.

The non-ionic surfactant(s) used in composition C according to the invention are preferably chosen from, alone or as a mixture:

- _C8 to _C40 alcohols, saturated or unsaturated, linear or branched, oxyethylenated comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50, more particularly from 2 to 40 moles of ethylene oxide; they preferably comprise one or two fatty chains;

- oxyethylenated vegetable oils, saturated or not, comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50;

- alkyl(C ₈ -C ₃₀ ) (poly)glycosides, optionally oxyalkylenated, preferably from 0 to 10 moles of ethylene oxide, and comprising 1 to 15 glucose units;

- _C8 to _C40 alcohols, mono- or polyglycerolated, comprising from 1 to 50 moles of glycerol, preferably from 1 to 10 moles of glycerol;

- amides of _C8 to _C30 fatty acids, saturated or unsaturated, linear or branched, oxyalkylenated;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of polyethylene glycols;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of sorbitol, preferably oxyethylenated.

More preferably, the non-ionic surfactant(s) used in composition C according to the invention are chosen from, alone or as a mixture,:

- _C8 to _C40 alcohols, saturated or unsaturated, linear or branched, oxyethylenated comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50, more particularly from 2 to 40 moles of ethylene oxide and comprising one or two fatty chains, in particular at least one C8-C20 alkyl chain, in particular C10-C18;

- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of sorbitol, preferably oxyethylenated, and

- alkyl(C ₈ -C ₃₀ ) (poly)glucosides, optionally oxyalkylenated, preferably comprising from 0 to 10 moles of ethylene oxide, and comprising 1 to 15 glucose units;

- oxyethylenated vegetable oils, saturated or not, comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50.

Preferably, composition C according to the invention comprises the non-ionic surfactant(s) in a total content ranging from 0.1 to 10% by weight, preferably from 0.2 to 7% by weight, preferentially from 0.5 to 4% by weight, relative to the total weight of the composition according to the invention.

Additional compounds

Composition C according to the invention advantageously comprises water, in particular at a concentration preferably ranging from 40 to 95% by weight, for example from 45 to 90% by weight, in particular from 50 to 85% by weight, better still from 60 to 85% by weight, relative to the total weight of the composition.

The pH of the composition can be between 2.5 and 8, preferably between 3 and 7, or even between 3.5 and 5.

Composition C according to the invention may optionally comprise one or more organic solvents, liquid at 25°C, 1 atm., preferably hydrophilic (soluble or miscible with water) which may be chosen from C1-C6 aliphatic or aromatic monoalcohols, C2-C8 polyols, and C3-C7 polyol ethers. Advantageously, the organic solvent is chosen from C2-C4 mono-, di- or tri-diols. It may advantageously be chosen from ethanol, isopropanol, benzyl alcohol, glycerol, propane 1,2-diol (propylene glycol) and mixtures thereof.

Composition C according to the invention may further comprise at least one or more usual cosmetic ingredients, in particular chosen from surfactants, in particular cationic surfactants; silicones; non-silicone liquid and/or solid fatty substances; thickeners and gelling agents; sunscreens; anti-dandruff agents; antioxidant agents; chelating agents; reducing agents; oxidation bases, couplers, oxidizing agents, direct dyes; straightening agents; pearlescent and opacifying agents; micas, pearlescent agents, glitter; pigments; fillers; perfumes; pH modifying agents. A person skilled in the art will take care to choose the ingredients included in the composition, as well as their quantities, so that they do not harm the properties of the compositions of the present invention.

In particular, composition C may advantageously comprise one or more thickeners, preferably chosen from thickening polymers, and even better from thickening polysaccharides, which may be of natural or synthetic origin.

Polysaccharides can be anionic, nonionic, cationic or amphoteric; they are preferably anionic or nonionic.

The basic units of polysaccharides can be mono- or disaccharides. The units that can be used in the composition of polysaccharides are preferably derived from the following sugars: glucose, galactose, arabinose, rhamnose, mannose, xylose, fucose, fructose, anhydrogalactose.

Examples of thickening polysaccharides include the following polymers and their derivatives:

- guar gum (polymer of mannose and galactose)

- carob gum (polymer of mannose and galactose)

- fenugreek gum (polymer of mannose and galactose)

- tamarind gum (polymer of galactose, xylose and glucose)

- konjac gum (polymer of glucose and mannose),

- scleroglucan gum (glucose polymer),

- cellulose (polymer of glucose)

- starch (polymer of glucose)

- inulin (polymer of fructose and glucose).

These polymers can be modified physically or chemically. Physical treatments include temperature. Chemical treatments include esterification, etherification, amidation, and oxidation reactions. These treatments produce polymers that can be non-ionic, cationic, or amphoteric.

The non-ionic guar gums that can be used according to the invention can be modified by C1-C6 hydroxyalkyl groups. Among the hydroxyalkyl groups, mention may be made of hydroxymethyl, hydroxyethyl, hydroxypropyl and hydroxybutyl groups. These guar gums are well known in the state of the art and can, for example, be prepared by reacting corresponding alkene oxides such as, for example, propylene oxides with guar gum, so as to obtain a guar gum modified by hydroxypropyl groups. The hydroxyalkylation rate preferably varies from 0.4 to 1.2 and corresponds to the number of alkylene oxide molecules consumed by the number of free hydroxyl functions present on the guar gum. Such non-ionic guar gums, possibly modified by hydroxyalkyl groups, are for example sold under the trade names JAGUAR HP8, JAGUAR HP60 and JAGUAR HP120 by the company RHODIA CHIMIE.

The guar gums modified by cationic groups which can be used more particularly according to the invention are guar gums comprising cationic trialkylammonium groups. Preferably, 2 to 30% by number of the hydroxyl functions of these guar gums carry cationic trialkylammonium groups. Even more preferably, 5 to 20% of the number of hydroxyl functions of these guar gums are connected by cationic trialkylammonium groups. Among these trialkylammonium groups, mention may be made in particular of trimethylammonium and triethylammonium groups. Even more preferably, these groups represent from 5 to 20% by weight relative to the total weight of the modified guar gum. According to the invention, guar gums modified by 2,3-epoxypropyltrimethylammonium chloride may be used. These guar gums modified by cationic groups are products already known in themselves and are for example described in patents US 3,589,578 and US 4,0131,307. Such products are sold in particular under the trade names JAGUAR C13 S, JAGUAR C 15, JAGUAR C 17 by the company RHODIA CHIMIE.

As a modified locust bean gum, cationic locust bean gum containing hydroxypropyltrimmonium groups such as Catinal CLB 200 offered by TOHO can be used.

The starch molecules used in the present invention may originate from any plant source of starch, in particular cereals and tubers; more particularly, they may be starches from corn, rice, cassava, barley, potato, wheat, sorghum, peas, oats, tapioca. Hydrolysates of the starches mentioned above or other starch derivatives may also be used. The starch is preferably derived from potatoes. Starches may be modified chemically or physically, in particular by one or more of the following reactions: pregelatinization, oxidation, crosslinking, esterification, etherification, amidation, heat treatments.

More specifically, these reactions can be carried out as follows:

- pregelatinization by bursting the starch granules (e.g. drying and cooking in a drying drum);

- oxidation by strong oxidants leading to the introduction of carboxyl groups into the starch molecule and to the depolymerization of the starch molecule (for example by treating an aqueous starch solution with sodium hypochlorite);

- crosslinking by functional agents capable of reacting with the hydroxyl groups of the starch molecules which will thus be linked together (for example with glyceryl and/or phosphate groups);

- esterification in alkaline medium for the grafting of functional groups, in particular C1-C6 acyl (acetyl), C1-C6 hydroxyalkyl (hydroxyethyl, hydroxypropyl), carboxymethyl, octenylsuccinic.

Among the starch derivatives, we can notably cite dextrins.

According to the invention, amphoteric starches may also be used, comprising one or more anionic groups and one or more cationic groups. The anionic and cationic groups may be linked to the same reactive site of the starch molecule or to different reactive sites; preferably they are linked to the same reactive site. The anionic groups may be of the carboxylic, phosphate or sulfate type, and preferably carboxylic. The cationic groups may be of the primary, secondary, tertiary or quaternary amine type.

Amphoteric starches are notably chosen from compounds with the following formulas:

in which:

St-O represents a starch molecule,

R, identical or different, represents a hydrogen atom or a methyl radical,

R', identical or different, represents a hydrogen atom, a methyl radical or a -COOH group,

n is an integer equal to 2 or 3,

M, identical or different, denotes a hydrogen atom, an alkali or alkaline earth metal such as Na, K, Li, NH4, a quaternary ammonium or an organic amine,

R" represents a hydrogen atom or a C1-C18 alkyl radical.

Particularly used are starches of formulae (IIa) or (IIIa); and preferably starches modified with 2-chloroethylaminodipropionic acid, i.e. starches of formula (IIa) or (IIIa) in which R, R', R" and M represent a hydrogen atom and n is equal to 2. The preferred amphoteric starch is a starch chloroethylamido dipropionate.

Celluloses and cellulose derivatives can be anionic, cationic, amphoteric, or non-ionic. These derivatives include cellulose ethers, cellulose esters, and cellulose ether esters.

Examples of non-ionic cellulose ethers include alkylcelluloses such as methylcelluloses and ethylcelluloses (e.g., Ethocel Standard 100 Premium from DOW CHEMICAL); hydroxyalkylcelluloses such as hydroxymethylcelluloses, hydroxyethylcelluloses (e.g., Natrosol 250 HHR offered by AQUALON) and hydroxypropylcelluloses (e.g., Klucel EF from AQUALON); mixed hydroxyalkyl-alkylcelluloses such as hydroxypropylmethylcelluloses (e.g., Methocel E4M from DOW CHEMICAL), hydroxyethylmethylcelluloses, hydroxyethylethylcelluloses (e.g., Bermocoll E 481 FQ from AKZO NOBEL) and hydroxybutylmethylcelluloses.

Among the cationic cellulose ethers, we can cite quaternized hydroxyethylcelluloses, crosslinked or not. The quaternizing agent can be diallyldimethylammonium chloride (for example, Celquat L200 from NATIONAL STARCH). Another cationic cellulose ether, we can cite hydroxyethylcellulose hydroxypropyltrimethylammonium (for example, Ucare polymer JR 400 from AMERCHOL).

Preferably, the composition comprises one or more thickening agents chosen from, alone or as a mixture, non-ionic polysaccharides, better chosen from, alone or as a mixture, non-ionic guar gums modified by C1-C6 hydroxyalkyl groups.

The composition according to the invention may comprise the thickening agent(s) in a total amount ranging from 0.05 to 10% by weight, in particular from 0.1 to 5% by weight, preferably from 0.15 to 3% by weight, relative to the total weight of the composition.

In particular, the composition according to the invention may comprise one or more non-ionic polysaccharides in a total amount ranging from 0.05 to 10% by weight, in particular from 0.1 to 5% by weight, preferably from 0.15 to 3% by weight, relative to the total weight of the composition.

The present invention is illustrated in more detail in the following examples (MA = active ingredient).

Example 1

The following compositions used in the context of the invention are prepared (% by weight of active material):

INCI NAME Composition A
step (i) AMINOPROPYL TRIETHOXYSILANE 10 POLYQUATERNIUM-6 1 Amino acids (glycine, arginine, serine, glutamic acid) 1.8 Citric acid 4.4 PEG-40 HYDROGENATED CASTOR OIL 2 Conservatives qs Water Qsp 100%

INCI NAME Composition C
step (iii) Glycerin 15 Propylene glycol 5 Amino acids (glycine, arginine, glutamic acid, serine) 5.8 Citric acid 3 Nonionic surfactant 2.5 Cationic polymer 1.2 Cationic surfactant 1 Thickening 0.2 Conservatives qs Water Qsp 100%

Apply composition A above to previously wet hair and leave for a few minutes (0 to 5 minutes).

Then, a standard shampoo composition (including anionic and amphoteric surfactants) is applied to unrinsed hair, washed in the usual way, and then the hair is rinsed with water.

Then apply composition C, leave it on for a few minutes before rinsing the hair with water, then dry it with a hairdryer or leave it to air dry.

Before drying, we notice that damp hair detangles very easily.

After drying, the hair appears repaired from within, visibly strengthened; detangling, smooth feel and elasticity of the hair are improved. Hair repair is even from root to tip.

The process according to the invention makes it possible to obtain the combination of repair at the heart of the fiber with instant detangling, particularly on damp hair, and a contribution of strength, all of which is long-lasting.

Example 2

The denaturation temperature of locks treated according to the invention is compared with that of comparative locks.

P1: Protocol according to the invention

Step 1: On strands of moderately sensitized hair (SA20), apply composition A from example 1 at a rate of 0.4g of composition per gram of strand. The composition is left on the hair for a pause time of 5 minutes.

Step 2: Apply a shampoo composition at a rate of 0.4g of composition per gram of strand. The strands are then rinsed with water.

Step 3: apply composition C from example 1, at a rate of 0.4g of composition per gram of strand, then rinse with water after 5 minutes of pause time.

Steps 2 and 3 are repeated 4 times.

P2: Comparative protocol

Step 1: On strands of moderately sensitized hair (SA20), apply the shampoo composition at a rate of 0.4g of composition per gram of strand. The strands are then rinsed with water.

Step 2: apply composition C, at a rate of 0.4g of composition per gram of strand, then rinse with water after 5 minutes of application time.

Steps 1 and 2 are repeated 4 times.

The integrity (i.e. repair) of the keratin fibers in the strands is then assessed by differential scanning calorimetry (also called DSC).

The principle of the test is to measure the protein denaturation temperature. The higher the protein denaturation temperature, the better the integrity of the cortex proteins, which indicates greater fiber strength.

We obtain the following results:

Untreated witness Protocol 1
invention Protocol 2
comparative Denaturation temperature (°C) 141.3 156.9 154

It is noted that protocol P1 according to the invention makes it possible to increase the denaturation temperature of the fiber proteins significantly compared to the comparative protocol P2.

The protocol according to the invention therefore makes it possible to improve the strengthening/repair of the hair.

Claims (15)

Cosmetic treatment process, preferably for hair, of keratin fibers, in particular hair, comprising:
- a step (i) of application to said keratin fibers of a cosmetic composition A comprising one or more organosilanes, then
- a step (ii) of washing said keratin fibers, comprising the application of a cosmetic washing composition B comprising one or more anionic surfactants and/or one or more amphoteric surfactants, then
- a step (iii) of application to said keratin fibers of a cosmetic composition C comprising one or more amino acid type compounds and one or more hydroxylated carboxylic (poly)acids, comprising 2 to 8 carbon atoms, and/or their salts. Process according to claim 1, in which composition A comprises one or more organosilanes chosen from the compounds of formula (I) and/or their oligomers and/or their hydrolysis products:
R1Si(OR2)z(R3)x(OH)y (I)
in which:
- R1 is a C1-C22, in particular C2-C20, linear or branched, saturated or unsaturated, cyclic or acyclic hydrocarbon chain, which may be substituted by a group chosen from the amine groups NH2 or NHR (R being a linear or branched C1-C20, in particular C1-C6, alkyl, or a C3-C40 cycloalkyl or a C6-C30 aromatic radical); the hydroxy group (OH), a thiol group, an aryl group (more particularly benzyl) substituted or not by an NH2 or NHR group; R1 may be interrupted by a heteroatom (O, S, NH) or a carbonyl group (CO);
- R2 and R3, identical or different, represent an alkyl group, linear or branched, comprising from 1 to 6 carbon atoms,
- y denotes an integer ranging from 0 to 3,
- z denotes an integer ranging from 0 to 3, and
- x denotes an integer ranging from 0 to 2, with z+x+y=3;
preferably, R1 is a C1-C12, in particular C2-C6, linear or branched, saturated hydrocarbon chain, substituted by an amine group NH2, R2 represents an alkyl group comprising from 1 to 4 carbon atoms, and z = 3 (and therefore x=y=0); better still, the organosilane(s) are chosen from methyltriethoxysilane (MTES), octyltriethoxysilane (OTES), dodecyltriethoxysilane, octadecyltriethoxysilane, hexadecyltriethoxysilane, 3-aminopropyl triethoxysilane (APTES); 2-aminoethyltriethoxysilane (AETES), 3-aminopropyl methyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, 3-(m-aminophenoxy) propyltrimethoxysilane, p-aminophenyltrimethoxysilane, N-(2-aminoethyl-aminomethyl)-phenethyltrimethoxysilane, and their oligomers, and/or their mixtures; and more particularly chosen from methyltriethoxysilane (MTES) and 3-aminopropyltriethoxysilane (APTES) and their oligomers, their hydrolysis products and/or their mixtures; and even better chosen from 3-aminopropyltriethoxysilane (APTES), its oligomers and/or its hydrolysis products. Method according to one of the preceding claims, in which the organosilane(s) are present in composition A in a total content of at least 6% by weight relative to the total weight of the composition, preferably at a total content ranging from 6 to 20% by weight, preferentially from 7 to 15% by weight, better still from 8 to 13% by weight, relative to the total weight of the composition. Process according to one of the preceding claims, in which the cosmetic composition A used in step (i) comprises one or more cationic polymers; preferably chosen from, alone or as a mixture:
- cyclopolymers of alkyldiallylamine or dialkyldiallylammonium, and in particular homopolymers or copolymers of salts (for example chloride) of dimethyldiallylammonium,
- optionally crosslinked homopolymers or copolymers of methacryloyloxyalkyl(C1-C4) trialkyl(C1-C4)ammonium salts;
- cationic celluloses and galactomannan gums. Process according to one of the preceding claims, in which the cosmetic composition A used in step (i) comprises one or more amino acid type compounds; preferably chosen from the compounds corresponding to formula (I) below and/or their salts:

in which p is an integer equal to 1 or 2, it being understood that:
- when p = 1, R forms with the nitrogen atom a saturated heterocycle comprising from 5 to 8 members, preferably 5 members, this cycle possibly being substituted by one or more groups chosen from hydroxyl or (C1-C4)alkyl;
- when p = 2, R represents a hydrogen atom or a (C1-C12)alkyl group, preferably (C1-C4)alkyl, linear or branched, saturated, optionally interrupted by one or more heteroatoms or groups chosen from –S–, –NH– or –C(NH)– and/or optionally substituted by one or more groups chosen from hydroxyl (OH), amino (NH2), -SH, -COOH, -CONH2, –NH–C(NH)–NH2 or a C5-C7 aryl group, in particular phenyl, itself optionally substituted by one or more OH;
preferably chosen from glycine, arginine, tyrosine, methionine, serine, glutamic acid, lysine, their salts (in particular of alkali or alkaline-earth metals, or of zinc) and their mixtures. Process according to one of the preceding claims, in which the cosmetic composition A used in step (i) comprises one or more hydroxylated (poly)carboxylic acids, comprising 2 to 8 carbon atoms, and/or their salts; preferably chosen from hydroxylated polycarboxylic acids and/or their salts comprising in total from 4 to 6 carbon atoms, from 1 to 3 OH groups and 2 to 3 COOH groups (in acid or salified form); in particular chosen from tartaric or citric acids, and their salts, in particular of alkali or alkaline earth metals. Method according to one of the preceding claims, in which the cosmetic washing composition B used in step (ii) comprises one or more anionic surfactants chosen from, alone or as a mixture,
- C6-C24 alkyl sulfates, especially C12-C20,
- C6-C24, especially C12-C20, alkyl ether sulfates; preferably comprising from 2 to 20 ethylene oxide units;
- C6-C24 alkylsulfosuccinates, in particular C12-C20, in particular laurylsulfosuccinates;
- C6-C24 olefinsulfonates, especially C12-C20,
- C6-C24 alkyl ether sulfosuccinates, in particular C12-C20;
- (C6-C24)acylisethionates, preferably (C12-C18)acylisethionates,
- C6-C24 acylsarcosinates, in particular C12-C20; in particular palmitoylsarcosinates and lauroylsarcosinates;
- alkyl(C6-C24)ethercarboxylates, preferably alkyl(C12-C20)ethercarboxylates; in particular those comprising from 2 to 50 ethylene oxide groups;
- polyoxyalkylenated alkyl(C6-C24)amidoethercarboxylic acids and their salts, in particular those containing from 2 to 50 alkylene oxide groups, in particular ethylene;
- C6-C24 acylglutamates, especially C12-C20;
- C6-C24 acylglycinates, especially C12-C20;
- C6-C24 alkylsulfoacetates, especially C12-C20,
in particular in acid form or as salts of alkali or alkaline earth metals, ammonium, or amino alcohol. Process according to one of the preceding claims, in which the cosmetic composition B used in step (ii) comprises one or more amphoteric surfactants chosen from alkyl(C ₈ -C ₂₀ )betaines, alkyl(C ₈ -C ₂₀ )sulfobetaines, alkyl(C ₈ -C ₂₀ )amidoalkyl(C ₃ -C ₈ )betaines and alkyl(C ₈ -C ₂₀ )amidalkyl(C ₆ -C ₈ )sulfobetaines, as well as the compounds of the following respective structures (II), (III) and (IV):
R _a -CONHCH ₂ CH ₂ -N ⁺ (R _b )(R _c )-CH ₂ COO ^- , M ⁺ , X ^- (II)
in which:
- R _a represents a C ₁₀ to C ₃₀ alkyl or alkenyl group derived from an acid R _a COOH, preferably present in hydrolyzed coconut oil, a heptyl, nonyl or undecyl group;
- R _b represents a beta-hydroxyethyl group; and
- R _c represents a carboxymethyl group;
- M ⁺ represents a cationic counterion from an alkali, alkaline earth metal, such as sodium, an ammonium ion or an ion from an organic amine, and
- X ^- represents an organic or inorganic anionic counterion, such as that chosen from halides, acetates, phosphates, nitrates, alkyl(C ₁ -C ₄ )sulfates, alkyl(C ₁ -C ₄ )- or alkyl(C ₁ -C ₄ )aryl-sulfonates, in particular methylsulfate and ethylsulfate; or else M ⁺ and X ^- are absent;
R _a' -CONHCH ₂ CH ₂ -N(B)(B') (III)
years in which:
- B represents the group -CH ₂ CH ₂ OX';
- B' represents the group -(CH ₂ ) _z Y', with z = 1 or 2;
- X' represents the group -CH ₂ COOH, -CH ₂ -COOZ', -CH ₂ CH ₂ COOH, CH ₂ CH ₂ -COOZ', or a hydrogen atom;
- Y' represents the group –COOH, -COOZ', -CH ₂ CH(OH)SO ₃ H or the group CH ₂ CH(OH)SO ₃ -Z';
- Z' represents a cationic counterion derived from an alkali or alkaline earth metal, such as sodium, an ammonium ion or an ion derived from an organic amine;
- R _a' represents a C ₁₀ to C ₃₀ alkyl or alkenyl group of an acid R _a' -COOH preferably present in coconut oil or in hydrolyzed linseed oil, an alkyl group, in particular C ₁₇ and its iso form, an unsaturated C ₁₇ group.
R _a'' -NHCH(Y'')-(CH ₂ ) _n CONH(CH ₂ ) _n' -N(R _d )(R _e ) (IV)
in which:
- Y'' represents the group –COOH, -COOZ'', -CH ₂ -CH(OH)SO ₃ H or the group CH ₂ CH(OH)SO ₃ -Z'';
- R _d and R _e , independently of one another, represent a C ₁ to C ₄ alkyl or hydroxyalkyl radical;
- Z'' represents a cationic counterion derived from an alkali or alkaline earth metal, such as sodium, an ammonium ion or an ion derived from an organic amine;
- R _a'' represents a C ₁₀ to C ₃₀ alkyl or alkenyl group of an acid R _a'' -COOH preferably present in coconut oil or in hydrolyzed linseed oil;
- n and n', independently of each other, denotes an integer ranging from 1 to 3;
Preferably chosen from alkyl(C8-C20)betaines such as cocobetaine, alkyl(C8-C20)amidoalkyl(C3-C8)betaines such as cocamidopropylbetaine and mixtures thereof. Process according to one of the preceding claims, in which the cosmetic composition C used in step (iii) comprises one or more amino acid type compounds chosen from the compounds corresponding to formula (I) below and/or their salts:

in which p is an integer equal to 1 or 2, it being understood that:
- when p = 1, R forms with the nitrogen atom a saturated heterocycle comprising from 5 to 8 members, preferably 5 members, this cycle possibly being substituted by one or more groups chosen from hydroxyl or (C1-C4)alkyl;
- when p = 2, R represents a hydrogen atom or a (C1-C12)alkyl group, preferably (C1-C4)alkyl, linear or branched, saturated, optionally interrupted by one or more heteroatoms or groups chosen from –S–, –NH– or –C(NH)– and/or optionally substituted by one or more groups chosen from hydroxyl (OH), amino (NH2), -SH, -COOH, -CONH2, –NH–C(NH)–NH2 or a C5-C7 aryl group, in particular phenyl, itself optionally substituted by one or more OH;
preferably, p=2 and R represents a hydrogen atom or a (C1-C4)alkyl group, linear or branched, saturated, optionally interrupted by a heteroatom –S– and/or optionally substituted by one or two groups chosen from hydroxyl, amino or –NH–C(NH)–NH2, better still R represents a hydrogen atom;
preferentially chosen from glycine, arginine, tyrosine, methionine, serine, glutamic acid, lysine, their salts (in particular of alkali or alkaline-earth metals, or of zinc) and their mixtures. Process according to one of the preceding claims, in which the cosmetic composition C used in step (iii) comprises one or more amino acid type compounds in a total content of at least 0.5% by weight relative to the total weight of the composition, better still ranging from 0.5 to 12% by weight, in particular from 1 to 10% by weight, better still from 2 to 8% by weight, even better still from 3 to 7% by weight, relative to the total weight of the composition. Process according to one of the preceding claims, in which the cosmetic composition C used in step (iii) comprises one or more hydroxylated (poly)carboxylic acids, comprising 2 to 8 carbon atoms, and/or their salts chosen from hydroxylated polycarboxylic acids and/or their salts comprising in total from 4 to 6 carbon atoms, from 1 to 3 OH groups and 2 to 3 COOH groups (in acid or salified form); better chosen from tartaric or citric acids, and their salts, in particular of alkali or alkaline-earth metals; very particularly sodium citrate and/or sodium tartrate; even better citric acid or its salts, in particular of alkali or alkaline-earth metals such as sodium citrate. Process according to one of the preceding claims, in which the cosmetic composition C used in step (iii) comprises one or more hydroxylated (poly)carboxylic acids comprising in total 2 to 8 carbon atoms, and/or their salts, in a total content of at least 0.5% by weight, in particular at least 1% by weight, relative to the total weight of the composition; better still ranging from 0.5 to 12% by weight, better still from 1 to 10% by weight, even better still from 1.5 to 8% by weight, or even from 2 to 7% by weight, relative to the total weight of the composition. Process according to one of the preceding claims, in which the cosmetic composition C used in step (iii) comprises one or more polyols, preferably chosen from diols and/or triols, comprising from 2 to 10 carbon atoms; in particular chosen from diglycerin, glycerin, propylene glycol, propane-1,3-diol, 1,3-butylene glycol, pentane-1,2-diol, octane-1,2-diol, dipropylene glycol, hexylene glycol, ethylene glycol, polyethylene glycols, sorbitol, sugars such as glucose and mixtures thereof; preferably from glycerin, propylene glycol, propane-1,3-diol, 1,3-butylene glycol, pentane-1,2-diol, octane-1,2-diol, dipropylene glycol, hexylene glycol, ethylene glycol, sorbitol and mixtures thereof; and even better from glycerin, propylene glycol, propane-1,3-diol, and mixtures thereof. Process according to one of the preceding claims, in which the cosmetic composition C used in step (iii) comprises one or more non-ionic surfactants; preferably chosen from, alone or as a mixture:
- _C8 to _C40 alcohols, saturated or unsaturated, linear or branched, oxyethylenated comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50, more particularly from 2 to 40 moles of ethylene oxide and comprising one or two fatty chains, in particular at least one C8-C20 alkyl chain, in particular C10-C18;
- esters of _C8 to _C30 acids, saturated or unsaturated, linear or branched, and of sorbitol, preferably oxyethylenated, and
- alkyl(C ₈ -C ₃₀ ) (poly)glucosides, optionally oxyalkylenated, preferably comprising from 0 to 10 moles of ethylene oxide, and comprising 1 to 15 glucose units;
- oxyethylenated vegetable oils, saturated or not, comprising from 1 to 100 moles of ethylene oxide, preferably from 2 to 50. Method according to one of the preceding claims, in which the cosmetic composition C used in step (iii) comprises one or more thickeners, preferably chosen from thickening polymers, and even better from thickening polysaccharides, preferably anionic or non-ionic.