A method of treating hair comprising applying a composition comprising an osmolyte, an amino acid, a polycarboxylic acid, and applying a hair smoothing composition comprising an alkanolamine

Abstract

The present invention relates to a hair treatment method comprising 1) applying a treatment composition comprising a) one or more osmolytes; b) one or more amino acids, (c) one or more polycarboxylic acids, one of their salts or their mixtures, and 2) applying a hair smoothing composition comprising: i) one or more alkanolamines, ii) one or more compounds chosen from amino acids and their derivatives, and iii) one or more alkali metal, alkaline earth metal or ammonium hydroxides 3) a step of smoothing / straightening the hair by mechanical means and heat. The invention also relates to a device with several compartments: a first compartment comprising the treatment composition and a second compartment comprising the smoothing composition.

Description

Title of the invention: A method of treating hair comprising applying a composition comprising an osmolyte, an amino acid, a polycarboxylic acid, and applying a hair smoothing composition comprising an alkanolamine, an amino acid and an alkali metal, alkaline earth metal or ammonium hydroxide.

[0001] The present invention relates to a method for treating hair, in particular a method for straightening / straightening hair. The invention further relates to a multi-compartment device for treating hair.

[0002] In the hair care field, consumers want to have compositions that allow them to make a temporary change to their hair, while aiming for a good hold of the effect achieved. In general, we want the change to persist after shampooing for at least 15 days, or even longer depending on the nature of the desired change.

[0003] Heat treatments are generally used to modify the shape of the hair, in a lasting way. These treatments allow a visual modification of the appearance of the hairstyle, combining a reduction in the degree of frizz, a reduction in the overall volume of the hair, a reduction in frizz, a gain in discipline, a smoother visual appearance, a substantial gain in shine, resistance to humidity and heat to maintain the hairstyle all day long.

[0004] Furthermore, this type of treatment has the advantage of facilitating daily hair care, with the use of fewer care products, in particular rinse-off treatments such as conditioners or masks, or leave-in treatments such as serums, treatment creams or balms, and shaping mousses. Hair drying is made easier, with significantly shorter brushing time and a reduction in the daily use of flat tongs, both in time and intensity. This thus limits the risks of hair damage from combined mechanical and thermal stress factors.

[0005] Several technologies are combined with these heat treatments. A first technology is based on the use of compositions based on thiolated reducers. These technologies require strict compliance with the application conditions recommended by the suppliers, particularly in terms of quantity and pause time. In addition, they may be contraindicated on overly sensitized hair and not be compatible with the application on the same day of other treatments such as coloring or bleaching. They are also smelly.

[0006] Another technology is based on the use of acid-based compositions, and in particular on the use of glyoxylic acid. Thus, application WO2011 / 104282 has proposed a new method for semi-permanently straightening hair, consisting of applying an alphaketoacid solution to the hair for 15 to 120 minutes, then drying and finally straightening the hair with an iron at a temperature of approximately 200°C. The alphaketoacid used is preferably glyoxylic acid.

[0007] However, it has been found that glyoxylic acid may not be well tolerated, particularly when the scalp is sensitive and / or irritated. Its volatility, amplified by the use of heat from the iron, may also be problematic. Furthermore, the compositions of the prior art may damage the hair and / or alter its color.

[0008] Treatments have also been proposed using a composition comprising a base combined with a heat treatment to straighten the hair. Such treatments make it possible to obtain good relaxation of the curls but can lead to alterations of the hair fiber. Document EP1837010 describes in particular a straightening / straightening method using a composition comprising soda and a heat treatment. Document WO2007 / 144707 describes a straightening / straightening method using a composition comprising a non-hydroxylated base such as monoethanolamine, ethylene diamine, combined with a heat treatment. Document WO2009 / 117344 also describes a straightening / straightening method using a composition comprising a non-hydroxylated base and a protein denaturant combined with a heat treatment.

[0009] To limit the alterations of hair fibers, it has also been proposed to use compositions comprising weak acids at alkaline pH combined with a heat treatment. Document WO2010 / 049434 describes, for example, a straightening / straightening process in which a composition comprising a dicarboxylic acid such as maleic acid and a heat treatment is applied. Such treatments are not always satisfactory in terms of results and / or persistence.

[0010] There is still a need to develop compositions, in particular for smoothing / straightening keratin fibers, which make it possible to smooth / straighten and / or reduce the frizz of the hair effectively and durably while limiting hair damage.

[0011] Thus, the present invention relates to a method for treating hair comprising 1) applying a treatment composition comprising a) one or more osmolytes; b) one or more amino acids, (c) one or more polycarboxylic acids, preferably hydroxylated, one of their salts or their mixtures, and 2) the application of a hair smoothing composition comprising: (i) one or more alkanolamines, (ii) one or more compounds selected from amino acids and their derivatives, and (iii) one or more alkali metal, alkaline earth metal or ammonium hydroxides 3) a step of smoothing / straightening the hair using mechanical means and heat.

[0012] The hair treatment method of the invention makes it possible to provide relaxation of the curls, that is to say straightening or smoothing of the hair, in an effective and lasting manner, the effect being persistent after shampooing and up to several weeks after treatment while limiting the damage to the hair.

[0013] The method of the invention can also be implemented on any type of hair, even very sensitized, and while preserving, or even improving, the cosmetic qualities of the hair, such as shine, smoothness, and ease of styling (reduction in volume and frizz) as well as their natural appearance with loose and light hair, as well as a natural feel.

[0014] The method according to the invention makes it possible in particular to obtain significant smoothing, lasting over time and with an improved cosmetic feel, in particular by making the hair smoother to the touch.

[0015] In the context of the present invention, the term "straightening / straightening" means a process which makes it possible to reduce the level of frizz in the hair; it also generally makes it possible to reduce the volume of the hair. The reduction in the level of frizz can go as far as completely straightening the hair. Other characteristics and advantages of the invention will appear more clearly on reading the description and the examples which follow.

[0016] In the following the expression “at least one” is equivalent to the expression “one or more”.

[0017] According to the process of the invention, the composition applied in step 1) comprises a) one or more osmolytes; b) one or more amino acids, (c) one or more polycarboxylic acids, preferably hydroxylated, one of their salts or their mixtures. Osmolytes a)

[0018] Osmolytes are organic molecules, generally of low molecular weight, which help to regulate the osmotic pressure between two entities, in response to external stress. In this case, the osmolyte helps to regulate the osmotic pressure between the exterior and interior of the hair during hair treatments.

[0019] According to the present invention, the term "osmolytes" does not include carboxylic amino acids, sulfonic amino acids or their salts.

[0020] The osmolytes can be chosen from: (i) carbohydrates, (ii) polyamines, and / or (iii) compounds of formula (I): (R1)(R2)(R3)m-A+-CR4R5-(X)nY (I) in which: - Rb R2 and R3, identical or different, represent a C1-C4 alkyl group, preferably a C1-C2 alkyl group, preferably methyl; - A is N or S; - m is 0 or 1; - n is 0 or 1; - X is a divalent, linear or branched, saturated or unsaturated alkyl group having from 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, optionally substituted by one or more groups chosen from a hydroxyl (-OH), an amino (-NH2); and - Y is -COO or -OSO3; it being understood that, - when A is S, then m=0 and R4 and R5, identical or different, represent a hydrogen atom or a saturated, unsaturated, linear, branched and / or cyclic hydrocarbon chain, in C1-C10, preferably in C1-C6, more preferably in C1-C4; optionally interrupted by one or more heteroatoms or groups chosen from - S-, -N=, -NH- or -C(NH)- and / or optionally substituted by one or more groups chosen from a hydroxyl (-OH), an amino (-NH2), -SH, -COOH, or -CONH2; - when A is N and m = 0, then R4 represents a hydrogen atom or a saturated, linear or branched C1-C8 alkyl group, preferably a C1-C4 alkyl group; and R5 forms, with the nitrogen atom, a saturated heterocycle comprising from 5 to 8 members, preferably from 5 to 6 members, optionally substituted by one or more groups chosen from hydroxyls or C1-C4 alkyls; and - when A is N and m = 1, then R4 and R5, identical or different, represent a hydrogen atom or a saturated, unsaturated, linear, branched and / or cyclic hydrocarbon chain in C1-C10, preferably in C1-C6, more preferably in C1-C4; optionally interrupted by one or more heteroatoms or groups chosen from -S-, -N=, -NH- or -C(NH)- and / or optionally substituted by one or more groups chosen from a hydroxyl (-OH), an amino (-NH2), -SH, -COOH or -CONH2.

[0021] The carbohydrates which can be used in the process according to the invention include polyols and sugars.

[0022] For example, the polyols may be selected from C2-C16 polyols, such as C2-C12 or C2-C8 polyols. Useful polyols may optionally be selected from diols and triols, and may optionally be linear or branched, saturated or unsaturated, and substituted or unsubstituted. Any stereoisomer of the polyols may be used. According to certain preferred embodiments, the polyols may be selected from glycols such as ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, pentylene glycol, 1,3-propanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, dipropylene glycol, caprylyl glycol, glycerin, diglycerin, ethylhexyl glycerin or mixtures of two or more of these.According to other preferred embodiments, the polyols may be selected from propanediol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, 1,2,6-hexanetriol, 1,2,4-butanetriol, trimethylolpropane, 2-butene-1,4-diol, 2-ethyl-1,3-hexanediol, 2-methyl-2,4-pentanediol, caprylyl glycol, 1,2-hexanediol, 1,2-pentanediol, 2-ethyl-2-methyl-1,3-propanediol, 3,3-dimethyl-1,2-butanediol, 2,2-diethyl-1,3-propanediol, 2-methyl-2-propyl-1,3-propanediol, 2,4-Dimethyl-2,4-Pentanediol, 2,5-Dimethyl-2,5-hexanediol, 5-Hexene-1,2-diol, 2-Ethyl-1,3-hexanediol, 4-Methyl-1,2-pentanediol, or mixtures of two or more of these.

[0023] Preferably, the polyols are chosen from glycerol, mannitol, xylitol, ribitol, pinitol, myoinositol, sorbitol and mixtures thereof.

[0024] For example, the sugars may be selected from C3-C6 monosaccharides, for example pentoses and / or their derivatives. For example, the sugars may optionally be selected from xylose, arabinose, ribose, 2-deoxy-ribose, ribulose, deoxy-ribulose, arabinose, xylulose, allose, altrose, glucose (including dextrose), glucosamine, mannose, gulose, idose, galactose, talose, sorbose, psicose, fructose, tagatose or combinations of two or more of these sugars. According to one embodiment, the sugars may be chosen from disaccharides, for example sucrose (also saccharose), maltose, lactose, cellobiose, trehalose, dextran, or from polysaccharides, for example maltotriose, starch, dextrins, cellulose, glycogen or combinations of two or more of them.

[0025] Preferably, the sugars are chosen from trehalose, glucose, sucrose, fructose, fructans, and mixtures thereof.

[0026] The polyamines which can be used in the process according to the invention can constitute functional groups of primary and / or secondary and / or tertiary and / or quaternary amines. By way of example, the polyamines can be chosen from diamines, triamines, tetramines, pentamines and polyamines. or polymeric polyimines, such as, for example, hexamethylenediamine, diethylenetramine, diethylenetriamine, polyethyleneimine (PEI), polyvinylamine, polyetheramine, polylysine, ethylenediamine, 1,3-diaminopropane, cadaverine, spermidine, spermine, putrescine, tetraethylmethylenediamine, triethylenetetramine, or combinations of two or more of these.

[0027] Preferably, the polyamines are chosen from putrescine, spermidine, spermine and mixtures thereof.

[0028] Preferably, the method according to the invention uses at least one osmolyte chosen from the compounds of formula (I).

[0029] Preferably, the method according to the invention uses at least one osmolyte chosen from the compounds of formula (I) which are derivatives of zwitterionic amino acids carrying a quaternary ammonium group and comprising in total from 1 to 12 carbon atoms, better still from 2 to 10 carbon atoms, better still from 3 to 8 carbon atoms.

[0030] Preferably, the process according to the invention uses at least one compound of formula (I) in which R1 and R2 are identical and represent an alkyl radical, preferably methyl.

[0031] Preferably, the method according to the invention uses at least one compound of formula (I) in which A is N.

[0032] Preferably, the method according to the invention uses at least one compound of formula (I) in which Y is -COO.

[0033] More preferably, the process according to the invention uses at least one compound of formula (I) in which R 1 and R 2 are identical and represent a methyl, A is N and Y is -COO.

[0034] Preferably, the process according to the invention uses at least one compound of formula (I) in which R3 is a methyl.

[0035] Preferably, X is a divalent, linear or branched, saturated or unsaturated alkyl group having from 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms.

[0036] Preferably, the process according to the invention uses at least one compound of formula (I) in which X is a divalent, linear or branched, preferably saturated alkyl group having from 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, optionally substituted by a group chosen from a hydroxyl or an amino.

[0037] In a particularly preferred manner, the process according to the invention uses at least one compound of formula (I) in which X is a divalent alkyl group, linear or branched, preferably saturated, having from 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms (unsubstituted), such as methylene or ethylene.

[0038] Preferably, the method according to the invention uses at least one compound of formula (I) in which R4 and R5, which may be identical or different, may be chosen from a hydrogen atom, a saturated, linear or branched alkyl group, C1-C10, preferably C1-C6, more preferably C1-C4; a phenyl group; a benzyl group; an alkyl group substituted by a cyclic group (saturated or unsaturated, mono or bicyclic); a cyclic group (saturated or unsaturated, mono or bicyclic) substituted by an alkyl group; all these groups being optionally interrupted by one or more heteroatoms or groups chosen from -S-, -N=, -NH- or -C(NH)- and / or optionally substituted by one or more groups chosen from hydroxyl (-OH), amino (-NH2), -SH, -COOH, -CONH2.

[0039] Preferably, the process according to the invention uses at least one compound of formula (I) in which R4 and R5 can be chosen from a hydrogen atom, a saturated, linear or branched C1-C6, preferably C1-C4 alkyl; optionally substituted by a group chosen from hydroxyl (-OH), amino (-NH2), -COOH or -CONH2.

[0040] In a particularly preferred manner, when A is N and m = 0, R5 forms, with the nitrogen atom, a saturated heterocycle comprising from 5 to 8 members, preferably 5 to 6 members, optionally substituted by a hydroxyl group.

[0041] Preferably again, the process according to the invention uses at least one compound of formula (I) in which Ri = R2 = methyl, A is N, Y is COO, and X, if present, is a divalent alkyl group which can be linear or branched, saturated or unsaturated, having from 1 to 6 carbon atoms, preferably from 1 to 4 carbon atoms, more preferably from 1 to 2 carbon atoms.

[0042] Preferably, the process according to the invention uses at least one compound of formula (I) in which R4 represents a hydrogen atom.

[0043] Preferably, the process according to the invention uses at least one compound of formula (I) in which R5 represents a hydrogen atom or a saturated, linear or branched C1-C6, preferably C1-C4, hydrocarbon chain, optionally substituted by one or more groups chosen from a hydroxyl (-OH), an amino (-NH2), -SH, -COOH or -CONH2.

[0044] Preferably, the process according to the invention uses at least one compound of formula (I) in which Ri = R2 = R3 = methyl; A is N; Y is COO; X is a divalent, linear or branched, preferably saturated alkyl group having from 1 to 4 carbon atoms, optionally substituted by a group chosen from a hydroxyl or a amino, preferably 1 to 2 carbon atoms (unsubstituted), such as methylene or ethylene; R4 is hydrogen; and R5 forms, with the nitrogen atom, a heterocycle saturated comprising 5 to 8 links, preferably 5 to 6 links, optionally substituted by a hydroxyl group.

[0045] Preferably, the compounds of formula (I) are chosen from one of the compounds indicated in FIG.l. ) y: Js' S «a,' s yj $ « X fefeîfe fesfe Wfesss fefe? fefeHfe fefe; ÜW fefes <fe Wsfe fesfe; rsW&Mn w i'fefe tefe rnj rfe rfe

[0046] Preferably, the compounds of formula (I) are chosen from valine betaine, glutamic acid betaine, glutamine betaine, trimethyllysine, glycine betaine (trimethylglycine), histidine betaine, alanine betaine, choline sulfate, betaine pipecolic acid, proline betaine, hydroxyproline betaine, tyrosine betaine, phenylalanine betaine, tryptophan betaine, leucine betaine, isoleucine betaine, dimethylsulfoniopropionate and mixtures thereof.

[0047] In a particularly preferred manner, the method according to the invention uses trimethylglycine (also called here glycine betaine or "betaine"), optionally in combination with at least one additional osmolyte, for example at least one additional compound of formula (I), preferably chosen from the compounds indicated in FIG. 1.

[0048] According to the invention, the osmolyte(s) used as compound (a) in the process according to the invention preferably represents from 0.05 to 10% by weight, preferably from 0.1 to 8% by weight, more preferably from 0.5 to 5% by weight, more preferably still from 0.8 to 4% by weight, better still from 1.0 to 3% by weight, relative to the total weight of the composition(s) containing them.

[0049] Preferably, the trimethylglycine used as compound (a) in the process according to the invention preferably represents from 0.05 to 10% by weight, preferably from 0.1 to 8% by weight, more preferably from 0.5 to 5% by weight, more preferably still from 0.8 to 4% by weight, better still from 1.0 to 3% by weight, relative to the total weight of the composition(s) containing them. Polycarboxylic acids c)

[0050] The method according to the invention uses one or more polycarboxylic acids. According to a particular embodiment, the polycarboxylic acid(s) are hydroxylated polycarboxylic acids.

[0051] Preferably, the polycarboxylic acid(s) is(are) chosen from the polycarboxylic acids of the following formula (II):

[0052] Formula (II) in which: - n is an integer between 1 and 5, better between 1 and 3, preferably n=1 or 2, more preferably n=2; - A is a multivalent, saturated or unsaturated, linear, branched, cyclic, or even aromatic hydrocarbon group, comprising from 1 to 6 carbon atoms, preferably from 1 to 4 carbon atoms, optionally substituted by one or more hydroxyl groups (OH).

[0053] Preferably, A is a multivalent (C1-C6)alkylene group, better (C2-C4)alkylene, or phenylene, substituted by one or more hydroxy groups.

[0054] Preferably, the hydroxylated polycarboxylic acids of formula (II) are alpha-hydroxy acids, for which A is a (C1-C6)alkylene group, better (C2-C4)alkylene, or phenylene group, substituted by 1 or 2 hydroxy groups, preferably 1 hydroxy group; and n = 1 to 2.

[0055] Mention may in particular be made of the hydroxylated polycarboxylic acids of formula (II) in which n = 1 or 2, and A is a di- or trivalent (Cl-C6)alkyl group, better still (C2-C4)alkyl, substituted by one or more hydroxyl groups, in particular 1 or 2 OH, preferably 1 OH.

[0056] Preferably, the hydroxylated polycarboxylic acids may be chosen from citric acid (n=2 and trivalent A = -CH2-CHOH-CH2-); - malic acid (n=1 and divalent A = -CH2-CH(OH)-); and - tartaric acid (n=1 and divalent A = -CH(OH)-CH(OH)-).

[0057] Even more preferably, the hydroxylated polycarboxylic acid, one of its salts or their mixtures is chosen from citric acid, one of its salts and their mixtures.

[0058] According to the invention, the hydroxylated polycarboxylic acid(s), one of their salts or their mixtures used as compound (c) in one or more composition(s) useful in the process according to the invention preferably represents from 0.05 to 20% by weight, preferably from 0.1 to 15% by weight, more preferably from 1 to 10% by weight, even more preferably from 2 to 8% by weight, relative to the total weight of the treatment composition.

[0059] Preferably, the citric acid, one of its salts or their mixtures used as compound (c) in the process according to the invention represents(s) from 0.05 to 20% by weight, preferably from 0.1 to 15% by weight, more preferably from 1 to 10% by weight, even more preferably from 2 to 8% by weight, relative to the total weight of the treatment composition. Amino acids b)

[0060] The amino acids which may be useful in the treatment composition of step 1) of the process of the invention may be basic, acidic or neutral at neutral pH.

[0061] In the context of the invention, the term "amino acid" includes carboxylic amino acids and their salts as well as aminosulfonic acids and their salts. In the present document, amino acids are understood to mean organic compounds containing a carboxylic acid group (—COOH) (carboxylic amino acids) and / or a sulfonic acid group (—S(=O)2-OH) (sulfonic amino acids) and an amino group (—NH2) which may be primary or secondary, or may be intracyclic, as well as a side chain (R group) specific to each amino acid.

[0062] The carboxylic amino acids which may be chosen, for example, from alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, valine and combinations of two or more of these compounds. Aminosulfonic acids may include aminomethane sulfonic acid, 2-aminoethane sulfonic acid (taurine), aminopropane sulfonic acid, aminobutane sulfonic acid, aminohexane sulfonic acid, aminoisopropyl sulfonic acid, aminododecyl sulfonic acid, aminobenzene sulfonic acid, aminotoluene sulfonic acid, sulfanilic acid, chlorosulfanilic acid, diamino benzene sulfonic acid, aminophenol sulfonic acid, amino propylbenzene sulfonic acid, amino hexyl benzene sulfonic acid, and combinations of two or more thereof.

[0063] Amino acid salts are also included in the term "amino acid", whether or not so indicated. By way of non-limiting example, salts that may be selected include organic or inorganic based salts, for example alkali metal salts, such as lithium, sodium or potassium salts; alkaline earth metal salts, such as magnesium or calcium salts; and zinc salts.

[0064] Additionally, the amino acids may be in the D, L, or DL ​​configuration. In certain preferred embodiments, it is advantageous to select amino acids in the L- configuration, for example, L-proline, L-methionine, L-serine, L-arginine, L-lysine, and combinations of two or more thereof.

[0065] In certain embodiments, it is particularly advantageous to choose one or more amino carboxylic acids. Thus, mention may be made of the amino acids of formula (I): COOH H — C — R

[0066] (I)

[0067] In which: - p is an integer equal to 1 or 2, andwhen p = 1, R forms, with the nitrogen atom, a saturated heterocycle comprising a ring of 5 to 8 members, preferably 5 members in which it is possible to substitute this ring with one or more groups chosen from hydroxyl or alkyl (C1-C4); orwhen p = 2, R represents a hydrogen atom or a saturated, linear or branched alkyl group (C1-C12), preferably an alkyl group (C1-C4), 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, -C0NH2, -NH-C(NH)-NH2, or an imidazole ring.

[0068] In certain embodiments, when p = 1, R forms, with the nitrogen atom, a saturated heterocycle comprising 5 ring members, this ring not being substituted.

[0069] In certain embodiments, when p = 2, R represents a hydrogen atom or a saturated, linear or branched alkyl group (C1-C4), optionally substituted by one or more groups chosen from hydroxyl (-OH), amino (-NH2), -CONH2 or -NH-C(NH)-NH2, or an imidazole ring. According to a particular embodiment, p is preferably 2.

[0070] In some embodiments, the composition of step 1) comprises one or more amino acids selected from glycine, proline, methionine, serine, arginine, lysine, histidine, salts of one of the above (in particular alkali metals, alkaline earth metals or zinc salts), or combinations of two or more thereof. In at least some embodiments, the amino acid compounds of the composition consist essentially of amino acids selected from glycine, proline, methionine, serine, arginine, lysine, histidine, salts of one of the above (in particular alkali metals, alkaline earth metals or zinc salts), or combinations of two or more thereof.According to a particular embodiment, the amino acid of the composition of step 1) is a basic amino acid, preferably comprising a guanidine group, preferably arginine.

[0071] The total amount of amino acids b) in the composition of step 1) in the process of the invention may vary from 0.1% to 15% by weight, preferably from 1% to 10% by weight, preferentially from 2% to 8% by weight relative to the total weight of the composition containing them. In the preferred embodiments, the total amount of amino acids varies from 2.5% to 7.5% by weight, better still from 3 to 7% by weight relative to the total weight of the composition containing them.

[0072] In a preferred embodiment, the treatment compositions comprise arginine and / or a salt thereof. In another preferred embodiment, where more than one amino acid is present, arginine is present in the treatment composition in an amount greater than the combined amounts of the other amino acid(s) present, e.g., arginine comprises more than about 50%, e.g., more than about 60%, more than about 70%, more than about 80%, more than about 90%, greater than about 95%, greater than about 98%, or greater than about 99% of all amino acids present in the composition. In another preferred embodiment, arginine is the only basic amino acid in the treatment composition.

[0073] In various preferred embodiments, the treatment composition comprises arginine in an amount ranging from 1% to 10% by weight, preferably from 2% to 8% by weight, more preferably from 2.5% to 7.5% by weight, better still from 3 to 7% by weight relative to the total weight of the composition containing it.

[0074] According to a particular embodiment, the treatment composition applied in step 1) comprises at least betaine (or trimethylglycine), citric acid and arginine. Preferably, this composition comprises from 0.5 to 5% of betaine, from 2 to 10% of citric acid and from 1 to 8% of arginine.

[0075] The treatment composition applied in step 1) is preferably aqueous, the water content preferably ranging from 10 to 90% by weight, more preferably from 30 to 85% by weight, better still from 50 to 80% by weight relative to the total weight of the composition.

[0076] When it is aqueous, the pH of said composition can vary from 1 to 8, preferably from 2 to 7, preferentially from 2.5 to 6. More preferentially the pH of the treatment composition is less than or equal to 5, better still from 3 to 5, better still from 3 to 4.5.

[0077] The hair straightening composition of step 2) comprises i) one or more alkanolamines, ii) one or more compounds selected from amino acids and their derivatives, and iii) one or more alkali metal, alkaline earth metal or ammonium hydroxides

[0078] Alkanolamines i) Alkanolamine means an organic amine comprising a primary, secondary or tertiary amine function, and one or more linear or branched C1-C8 alkyl groups carrying one or more hydroxyl radicals.

[0079] Particularly suitable for carrying out the invention are alkanolamines chosen from mono-, di- or tri-alkanolamines, comprising 1 to 3 hydroxyalkyl radicals, identical or not, in C1-C4.

[0080] In particular, the alkanolamine(s) are chosen from monoethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, N,N-dimethylethanolamine, 2-amino-2-methyl-1-propanol, triisopropanolamine, 2-amino-2-methyl-1,3-propanediol, 3-amino-1,2-propane diol, 3-dimethylamino-1,2-propanediol, tris-hydroxymethylamino-methane and mixtures thereof.

[0081] Preferably, the alkanolamine is monoethanolamine.

[0082] Preferably, the alkanolamine(s) are present in a total content ranging from 0.5 to 15% by weight, preferably from 1 to 10% by weight, more preferably from 2 to 8% by weight, better still from 3 to 7% by weight, relative to the total weight of the composition.

[0083] Preferably, the alkanolamine(s) chosen from monoethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, N,N-dimethylethanolamine, 2-amino-2-methyl-1-propanol, triisopropanolamine, 2-amino-2-methyl-1,3-propanediol, 3-amino-1,2-propanediol, 3-dimethylamino-1,2-propanediol, tris-hydroxymethylamino-methane and mixtures thereof are present in a total content ranging from 0.5 to 15% by weight, preferably from 1 to 10% by weight, more preferably from 2 to 8% by weight, better still from 3 to 7% by weight, relative to the total weight of the composition.

[0084] Preferably, the monoethanolamine is present in a total content ranging from 0.5 to 15% by weight, preferably from 1 to 10% by weight, more preferably from 2 to 8% by weight, better still from 3 to 7% by weight, relative to the total weight of the composition. Amino acids and derivatives ii)

[0085] The composition according to the invention further comprises at least one compound chosen from amino acids such as carboxylic amino acids or sulfonic amino acids, and their derivatives,

[0086] Useful amino acids are, for example, those described previously for the composition of step 1.

[0087] The amino acid(s) or their salt(s) may be chosen from aspartic acid, glutamic acid, asparagine, carnitine, glutamine, histidine, leucine, isoleucine, methionine, N-phenylalanine, proline, hydroxyproline, threonine, tryptophan, tyrosine, valine, glycine, alanine, serine, beta alanine, taurine, lysine, arginine and their salts, in particular sodium glycinate, sodium alanilate, sodium serinate, lithium beta alaninate, sodium taurate.

[0088] Preferably, the amino acids are chosen from sulfonic amino acids, preferentially from those of the following formula (II), as well as their betaine forms, their optical isomers, their solvates such as hydrates, and their salts, of acid or base, organic or mineral: Gold- R in which: - R represents a hydrogen atom, a linear or branched C1-C5 alkyl group, preferably linear, said alkyl group being optionally substituted by at least one group chosen from hydroxyl, amino, -C(O)-OH, -S(O)2-OH, -C(O)-O, M+ , -S(0)2-0, M+, with M+ representing a cationic counterion such as alkali metal, alkaline earth metal, or ammonium, - n is 0 or 1.

[0089] In the composition of step 2), the amino acid(s) may be found in their non-ionized form (II) or in their ionized or betaine form (II'): 00 on Formulas in which R represents a hydrogen atom, a linear or branched C|-C5 alkyl group, optionally substituted by a hydroxyl, amino, or carboxylate group, n is 0 or 1.

[0090] According to a particular embodiment, the amino acid present in the smoothing composition is more preferably taurine.

[0091] In particular, the composition according to the invention comprises at least one compound chosen from taurine, as well as its betaine forms, its optical isomers, its solvates such as hydrates, and its salts, of acid or base, organic or mineral, and their mixtures.

[0092] Taurine, or 2-aminoethanesulfonic acid, is an amino acid of formula NH2-CH2-CH2-SO3H. Taurine may be present in non-ionized form (II') or in ionized form (II”), as defined above.

[0093] Preferably, the compound(s) chosen from taurine and its derivatives are chosen from taurine and its salts, in particular sodium taurate, potassium taurate, magnesium taurate, and mixtures thereof, more preferably taurine.

[0094] Preferably, the compound(s) chosen from amino acids and their derivatives ii) in the smoothing composition are present in a total content ranging from 0.5 to 15% by weight, preferably from 0.75 to 10% by weight, preferentially from 1 to 6% by weight, better still from 2 to 5% by weight relative to the total weight of the composition.

[0095] Preferably, the compound(s) chosen from sulfonic amino acids and their derivatives are present in a total content ranging from 0.5 to 15% by weight, preferably from 0.75 to 10% by weight, preferentially from 1 to 6% by weight, better still from 2 to 5% by weight relative to the total weight of the smoothing composition.

[0096] Preferably, the compound(s) chosen from taurine and its derivatives are present in a total content ranging from 0.5 to 15% by weight, preferably from 0.75 to 10% by weight, preferentially from 1 to 6% by weight, better still from 2 to 5% by weight, relative to the total weight of the composition.

[0097] Preferably, potassium taurate, sodium taurate, magnesium taurate and taurine, and preferentially taurine, are present in a total content ranging from 0.5 to 15% by weight, preferably from 0.75 to 10% by weight, preferentially from 1 to 6% by weight, better still from 2 to 5% by weight, relative to the total weight of the composition.

[0098] Alkali metal, alkaline earth metal or ammonium hydroxides iii) The smoothing composition further comprises one or more alkali metal, alkaline earth metal or ammonium hydroxides.

[0099] By alkali or alkaline earth metal hydroxide is meant a compound of formula M(OH)x in which M is a metal chosen from alkali or alkaline earth metals and x is equal to 1 or 2. The alkali metal hydroxides may in particular be chosen from sodium hydroxide, potassium hydroxide, and mixtures thereof. The alkaline earth metal hydroxides may in particular be chosen from magnesium hydroxide, calcium hydroxide, and mixtures thereof.

[0100] Ammonium hydroxide is the compound with the formula NH4OH.

[0101] Preferably, the alkali metal or alkaline earth metal hydroxide(s) will be used.

[0102] Preferably, the alkali metal or alkaline earth metal hydroxide(s) are chosen from alkali metal hydroxides, and mixtures thereof, preferentially from sodium hydroxide, potassium hydroxide, and mixtures thereof.

[0103] Preferably, the alkali metal, alkaline earth metal or ammonium hydroxide(s) are present in a total content ranging from 0.05 to 10% by weight, preferably from 0.1 to 5% by weight, preferentially from 0.5 to 3% by weight, better still from 0.6 to 2% by weight relative to the total weight of the composition.

[0104] Preferably, the alkali or alkaline earth metal hydroxide(s) are present in a total content ranging from 0.05 to 10% by weight, preferably from 0.1 to 5% by weight, preferentially from 0.5 to 3% by weight, better still from 0.6 to 2% by weight, relative to the total weight of the composition.

[0105] Preferably, the composition according to the invention comprises at least one alkali metal hydroxide which may be present in a total content ranging from 0.05 to 10% by weight, preferably from 0.1 to 5% by weight, preferentially from 0.5 to 3% by weight, better still from 0.6 to 2% by weight, relative to the total weight of the composition.

[0106] Preferably, sodium hydroxide, potassium hydroxide, and mixtures thereof are present in a total content ranging from 0.05 to 10% by weight, preferably from 0.1 to 5% by weight, preferentially from 0.5 to 3% by weight, better still from 0.6 to 2% by weight, relative to the total weight of the composition.

[0107] According to a particular embodiment, the smoothing / straightening composition comprises at least one amino sulfonic acid, an alkanolamine and sodium and / or potassium hydroxide.

[0108] According to a particular embodiment of the smoothing composition, the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from amino acids and their derivatives is greater than 1.

[0109] According to this embodiment, the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from amino acids and their derivatives is between 1.1 and 5, preferably between 1.2 and 3, better still between 1.3 and 2.

[0110] Preferably, the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from sulfonic amino acids and their derivatives is strictly greater than 1, preferably strictly greater than 1.1, better still greater than 1.2.

[0111] Preferably, the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from sulfonic amino acids and their derivatives is between 1.1 and 5, preferably between 1.2 and 3, better still between 1.3 and 2.

[0112] Preferably, the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from taurine and its derivatives is greater than 1, preferably greater than 1.1, better still greater than 1.2.

[0113] Preferably, the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from taurine and its derivatives is between 1.1 and 5, preferably between 1.2 and 3, better still between 1.3 and 2.

[0114] Preferably, the weight ratio between the total content of monoethanolamine and the total content of potassium taurate, sodium taurate, magnesium taurate, taurine and their mixtures is greater than 1, preferably greater than 1.1, better still greater than 1.2.

[0115] Preferably, the weight ratio between the total content of monoethanolamine and the total content of potassium taurate, sodium taurate, magnesium taurate, taurine and their mixtures is between 1.1 and 5, preferably between 1.2 and 3, better still between 1.3 and 2.

[0116] Preferably, the weight ratio between the total monoethanolamine content and the total taurine content is greater than 1, preferably greater than 1.1, better still greater than 1.2.

[0117] Preferably, the weight ratio between the total monoethanolamine content and the total taurine content is between 1.1 and 5, preferably between 1.2 and 3, better still between 1.3 and 2.

[0118] Preferably, the weight ratio between the total content of alkanolamine(s) and the total content of alkali metal, alkaline earth metal or ammonium hydroxides is greater than 1, preferably between 2 and 10, more preferably between 4 and 8.

[0119] Preferably, the weight ratio between the total content of alkanolamine(s) and the total content of alkali or alkaline-earth metal hydroxides is greater than 1, preferably between 2 and 10, more preferably between 4 and 8.

[0120] Preferably, the weight ratio between the total content of monoethanolamine and the total content of sodium hydroxide and / or potassium hydroxide is greater than 1, preferably between 2 and 10, more preferably between 4 and 8.

[0121] Preferably, the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from amino acids and their derivatives and of alkali metal, alkaline earth metal or ammonium hydroxide(s) is greater than 1, preferably between 1.1 and 3, more preferably between 1.1 and 2.

[0122] Preferably, the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from taurine and its derivatives and alkali metal hydroxide(s) is greater than 1, preferably between 1.1 and 3, more preferably between 1.1 and 2

[0123] Preferably, the smoothing composition is an aqueous composition. It may in particular comprise water or water and one or more solvents. Preferably, the water content generally ranges from 10 to 99% by weight, preferably from 30 to 95% by weight, preferentially from 40 to 90% by weight relative to the total weight of the composition.

[0124] As solvents, organic solvents are preferred. Mention may in particular be made of water-soluble solvents such as C1-C7 alcohols; mention may in particular be made of C1-C7 aliphatic monoalcohols, for example ethanol, or C6-C7 aromatic monoalcohols, or C2-C6 polyols, such as for example glycerin, pentylene glycol, which may be used alone or in a mixture with water.

[0125] When the composition is aqueous, the pH preferably varies from 7 to 13, preferentially from 8 to 12.5, better still from 9 to 12, better still from 10 to 11.5.

[0126] Preferably, the smoothing composition comprises: - at least one alkanolamine, - at least one compound chosen from taurine and its derivatives, and - at least one alkali or alkaline earth metal hydroxide, preferably at least one alkali metal hydroxide; with optionally a weight ratio between the total content of alkanolamine(s) and the total content of taurine and / or its derivatives greater than 1.

[0127] Preferably, the alkanolamine(s) are chosen from the group consisting of monoethanolamine, diethanolamine and triethanolamine, monoisopropanolamine, diisopropanolamine, and mixtures thereof, more preferably monoethanolamine.

[0128] Preferably, the alkali metal hydroxide(s) is(are) chosen from the group consisting of sodium hydroxide, potassium hydroxide and mixtures thereof.

[0129] Thickening agents The compositions useful in the process of the invention may also comprise one or more thickening agents. For the purposes of the present invention, the term "thickening agent" means an agent which, by its presence in the composition, makes it possible to increase the viscosity of said composition by at least 10 cPs, preferably by at least 200 cPs, at 25°C and at a shear rate of 1 s-1. This viscosity can be measured using a cone / plate viscometer (Haake R600 Rheometer or similar).

[0130] The thickening agent(s) may be chosen from fatty acid amides obtained from C10-C30 carboxylic acid (monoisopropanol-, diethanol- or monoethanol-amide of coconut acids, monoethanolamide of oxyethylenated alkyl ether carboxylic acid), polymeric thickeners and in particular polysaccharides, in particular cellulose polymers as described below, guar gums, gum arabic, gums of microbial origin (scleroglucan gum), crosslinked or non-crosslinked homo- and copolymers based on acrylic acid, methacrylic acid or acrylamidopropanesulfonic acid, and mixtures thereof.

[0131] According to one variant, the thickening polymer is a polysaccharide of natural or synthetic origin. The polysaccharide polymers useful in the invention are cationic, non-ionic, anionic or amphoteric polymers, preferably non-ionic. The term "polysaccharide polymers" means polymers with sugar units.

[0132] By sugar unit is meant, within the meaning of the present invention, a unit derived from a carbohydrate of formula Cn(H2O)ni or (CH2O)n which may optionally be modified by substitution, and / or by oxidation and / or by dehydration.

[0133] As sugar units, polymers useful in the invention are preferably derived from the following sugars: glucose; galactose; arabinose; rhamnose; mannose; xylose; fucose; anhydrogalactose; galacturonic acid; glucuronic acid; mannuronic acid; galactose sulfate; anhydrogalactose sulfate and fructose.

[0134] Examples of polysaccharide polymers that may be mentioned include those derived from native gums such as:

[0135] a) exudates from trees or shrubs including: - gum arabic (branched polymer of galactose, arabinose, rhamnose and glucuronic acid); - gum ghatti (polymer derived from arabinose, galactose, mannose, xylose and glucuronic acid); - karaya gum (polymer derived from galacturonic acid, galactose, rhamnose and glucuronic acid); - gum tragacanth (or tragacanth) (polymer of galacturonic acid, galactose, fucose, xylose and arabinose);

[0136] b) gums derived from algae including: - agar (polymer made from galactose and anhydrogalactose); - alginates (polymers of mannuronic acid and glucuronic acid); - carrageenans and furcellerans (polymers of galactose sulfate and anhydrogalactose sulfate);

[0137] c) gums from seeds or tubers of which: - 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);

[0138] d) microbial gums including: - xanthan gum (polymer of glucose, mannose acetate, mannose / pyruvic acid and glucuronic acid); - gellan gum (polymer of partially acylated glucose, rhamnose and glucuronic acid); - scleroglucan gum (glucose polymer);

[0139] e) plant extracts including: - cellulose (glucose polymer); - starch (glucose polymer) and - inulin.

[0140] These polymers can be modified physically or chemically. Physical treatment includes, in particular, temperature.

[0141] As chemical treatments, mention may be made of esterification, etherification, amidation and oxidation reactions. These treatments make it possible to produce polymers which may be, in particular, non-ionic, anionic or amphoteric.

[0142] Preferably these chemical or physical treatments are applied to guar gums, carob gums, starches and celluloses.

[0143] Such non-ionic guar gums optionally modified by hydroxyalkyl groups are for example sold under the names JAGUAR HP8, JAGUAR HP60, JAGUAR HP 105 and JAGUAR HP120 commercials by the company RHODIA CHIMIE.

[0144] The polysaccharide polymers may be cellulosic polymers.

[0145] Thus, the cellulose polymers can be chosen from unsubstituted celluloses including in microcrystalline form and cellulose ethers.

[0146] Among these cellulose polymers, we distinguish cellulose ethers, cellulose esters and cellulose ether esters.

[0147] Among the cellulose esters, there are inorganic cellulose esters (nitrates, sulfates or phosphates of cellulose, etc.), organic cellulose esters (monoacetates, triacetates, amidopropionates, acetatebutyrates, acetatepropionates or acetatetrimellitates of cellulose, etc.) and mixed organic / inorganic cellulose esters such as cellulose acetatebutyratesulfates and acetatepropionatesulfates. Among the cellulose ether esters, there are hydroxypropylmethylcellulose phthalates and ethylcellulose sulfates.

[0148] Among the non-ionic cellulose ethers without fatty chain in C10-C30 ie "non-associative", we can cite (Cl-C4)alkylcelluloses such as methylcelluloses and ethylcelluloses (for example Ethocel standard 100 Premium from DOW CHEMICAL); (poly)hydroxy(Cl-C4)alkylcelluloses such as hydroxymethylcelluloses, hydroxyethylcelluloses (for example Natrosol 250 HHR offered by AQUALON) and hydroxypropylcelluloses (for example Klucel EF from AQUALON); mixed celluloses (poly)hydroxy(Cl-C4)alkyl-(Cl-C4)alkylcelluloses such as hydroxypropyl-methylcelluloses (for example Methocel E4M from DOW CHEMICAL), hydroxyethyl-methylcelluloses, hydroxyethyl-ethylcelluloses (for example Bermocoll E 481 FQ from AKZO NOBEL) and hydroxybutyl-methylcelluloses.

[0149] The polysaccharide(s) according to the invention may be chosen from microbial gums.

[0150] The microbial gums may be selected from scleroglucan gums, gellan gums, pullulan gums, Curdlar gums, xanthan gums, grifolan gums, lentinan gums, Schizophyllan gums, spirulinan gums and krestin gums.

[0151] Mention may in particular be made of scleroglucan gums produced by Sclerotium rolfsii, gellan gums produced by Pseudomonas elodea or Sphingomonias, pullulan gums produced by Aureobacidium pullulens, Curdlar gums produced by alcaligenes of the Faecalis myxogenes type, xanthan gums produced by numerous organisms including Leuconostoc mesenteroides and Leuconostoc dextrantum, grifolan gums produced by Grifola frondara, lentinan gums produced by Lentinus edodes, Schizophyllan gums produced by Schizophyllum commine, spirulinan gums produced by Spirulina sybsyla and krestin gums produced by Coriates versicolor.

[0152] Preferably, the thickening agent(s) are chosen from polysaccharides, preferentially from guar gums, better still from non-ionic guar gums optionally modified by hydroxyalkyl groups.

[0153] When present, the thickening agent(s) is or are generally present in a content ranging from 0.1 to 10% by weight and preferably from 0.5 to 5% by weight, better still from 1 to 3% by weight, relative to the total weight of the composition.

[0154] When present, the polysaccharide polymer(s) is or are generally present in a content ranging from 0.1 to 10% by weight and preferably from 0.5 to 5% by weight, better still from 1 to 3% by weight, relative to the total weight of the composition.

[0155] Cationic polymers The compositions useful in the process of the invention may also comprise one or more cationic polymers, preferably non-silicone, different from the thickening agents previously described. The cationic polymer(s) which can be used may be chosen from associative cationic polymers, non-associative cationic polymers and mixtures thereof.

[0156] For the purposes of the present invention, the term "cationic polymer" means any polymer comprising cationic groups and / or groups which can be ionized into cationic groups. The preferred cationic polymers are chosen from those which contain units comprising primary, secondary, tertiary and / or quaternary amine groups which can either form part of the main polymer chain or be carried by a side substituent directly linked to it.

[0157] The cationic polymers optionally present in the composition according to the invention may be chosen from all those already known per se as improving the cosmetic properties of the hair, namely in particular those described in patent application EP-A-337 354 and in French patents FR-2 270 846, 2 383 660, 2 598 611, 2 470 596 and 2 519 863.

[0158] The polymer(s) are chosen from non-silicone polymers.

[0159] The preferred cationic polymers are chosen from those which contain units comprising primary, secondary, tertiary and / or quaternary amine groups which can either form part of the main polymer chain or be carried by a side substituent directly linked to it. Among the cationic polymers, mention may be made more particularly of polymers of the polyamine, polyaminoamide and polyquaternary ammonium type. These are known products. They are described in particular in French patents Nos. 2,505,348 or 2,542,997.

[0160] Preferably, the cationic polymer(s) used in the smoothing composition is or are chosen from the homopolymer of dimethyldiallylammonium chloride, with the INCI name Polyquaternium-6, such as the product sold under the name "Merquat 100" by the company NALCO (and its counterparts with low weight average molecular mass) and the copolymers of diallyldimethylammonium chloride and acrylamide, with the INCI name Polyquaternium-7, such as the products sold under the name "MERQUAT 550", "MERQUAT 7SPR".

[0161] The cationic polymer(s) used in the composition according to the invention may be present in a content ranging from 0.05 to 10% by weight, preferably in a content ranging from 0.1 to 5% by weight, preferentially from 0.2 to 3% by weight relative to the total weight of the composition.

[0162] According to one variant, the composition of the invention comprises at least one thickening agent chosen from polysaccharides and at least one cationic polymer as defined previously.

[0163] Surfactants The compositions useful in the process of the invention may also comprise one or more surfactants, preferably chosen from non-ionic surfactants and cationic surfactants.

[0164] Preferably, the surfactant(s) are preferably chosen from non-ionic surfactants. Among the non-ionic surfactants, it is possible to use oxyalkylenated fatty alcohols, in particular oxyethylenated fatty alcohols, preferably C8-C24 fatty alcohols comprising 1 to 50 moles of ethylene oxide.

[0165] When it(they) is(are) present, the total content of surfactant(s) can range from 0.1 to 20% by weight, preferably from 1 to 15% by weight, preferentially from 2 to 10% by weight, relative to the total weight of the composition.

[0166] Fatty substances The compositions useful in the process of the invention may comprise one or more fatty substances. The fatty substance(s) are preferably chosen from liquid hydrocarbons comprising more than 6 carbon atoms, C8-C30 fatty alcohols, silicones and mixtures thereof.

[0167] By way of example, liquid hydrocarbons comprising more than 6 carbon atoms may be chosen from C6 to C16 liquid hydrocarbons, the latter may be linear, branched, optionally cyclic, and preferably saturated. Mention may be made of hexane, cyclohexane, undecane, dodecane, isododecane, tridecane, isoparaffins such as isohexadecane, isodecane, and mixtures thereof.

[0168] Liquid hydrocarbons comprising more than 6 carbon atoms may also be chosen from liquid hydrocarbons comprising more than 16 carbon atoms, linear or branched, of mineral or synthetic origin, and are chosen preferably among paraffin or vaseline oils (or mineral oil), polydecenes, hydrogenated polyisobutene such as Parléam®, and mixtures thereof.

[0169] Liquid hydrocarbons comprising more than 6 carbon atoms may also be chosen from mixtures of alkanes having from 8 to 28 carbon atoms, more particularly from 15 to 28 carbon atoms, we may cite the mixtures whose INCI names are for example the following: C15-19 Alkane, C18-C21 Alkane, C21-C28 Alkane, such as for example the products Gemseal 40, Gemseal 60, Gemseal 120 marketed by Total, Emogreen L19 marketed by SEPPIC, Emogreen L15 marketed by SEPPIC, more particularly Emogreen L19 marketed by SEPPIC.

[0170] The C8-C30 fatty alcohols are preferably chosen from C8-C24 fatty alcohols, preferentially C12-C22.

[0171] The fatty alcohols can be chosen from cetyl alcohol, stearic alcohol, and their mixtures such as cetearyl alcohol.

[0172] Preferably, the fatty substances are preferably chosen from liquid hydrocarbons comprising more than 6 carbon atoms, C8-C30 fatty alcohols, silicones and their mixtures, preferentially from liquid hydrocarbons comprising more than 6 carbon atoms, C8-C30 fatty alcohols, and their mixtures.

[0173] When it(they) is(are) present, the total fatty substance content can range from 0.1 to 20% by weight, preferably from 1 to 15% by weight, preferentially from 5 to 10% by weight relative to the total weight of the composition.

[0174] The compositions useful in the process according to the invention can be presented in all the galenic forms conventionally used, and in particular in the form of an aqueous, alcoholic or hydroalcoholic, or oily solution or suspension; of a solution or dispersion of the lotion or serum type; of an emulsion, in particular of liquid or semi-liquid consistency, of the O / W, W / O or multiple type; of a suspension or emulsion of soft consistency of the cream (O / W) or (W / O) type; of an aqueous or anhydrous gel, of a cream or of any other cosmetic form.

[0175] Method The hair treatment method of the invention is in particular a hair straightening and / or relaxing method which comprises: 1) a step of applying to the hair the treatment composition as described previously, 2) a step of applying to the hair a smoothing composition as described previously 3) a step of straightening the hair by mechanical means and heat.

[0176] Preferably, the treatment composition of step 1 comprises at least one polycarboxylic acid, preferably hydroxylated, preferably citric acid, at least one osmolyte, preferably betaine, at least one amino acid, preferably a carboxylic amino acid, preferably arginine.

[0177] According to one embodiment, the smoothing composition comprises at least one sulfonic amino acid, at least one alkanolamine, and at least one alkaline hydroxide, preferably sodium hydroxide.

[0178] According to a particular embodiment, step 3) of smoothing (straightening) is carried out at a temperature above 50°C, preferably between 90 and 280°C, preferably from 100 to 250°C. The mechanical means which allow the smoothing / straightening of the hair are for example the use of a comb, a brush or a straightening iron.

[0179] According to a first embodiment, step 1) is implemented before step 2), step 2 being followed by step 3. In this embodiment, the composition of step 1 and the composition of step 2 can be superimposed or a rinsing step can be implemented after step 1 and before step 2. Preferably, according to this embodiment, step 1 is implemented, it is followed by a rinsing step then the application of step 2. Step 2 is then followed by a rinsing step, drying the hair with a hair dryer then the implementation of step 3, preferably with a hair straightener.

[0180] Preferably, step 1) is implemented after step 2)

[0181] According to another embodiment, step 1) is implemented after step 2), step 1 then being followed by step 3. In this embodiment, the composition of step 1 and the composition of step 2 can be superimposed or a rinsing step can be implemented after step 2 and before step 1. Preferably, according to this embodiment, step 2 is implemented, it is followed by a rinsing step and then step 1 is implemented. After rinsing following step 1, the hair is dried with a hair dryer and then step 3 is implemented, preferably with a straightening iron.

[0182] According to a third embodiment, the method of the invention comprises step 2, a rinsing step followed by drying the hair with a hair dryer, step 3 is then implemented, preferably with a hair straightener. The hair is then shampooed immediately or 1 to several days after step 3 and step 1 is implemented, after an optional pause time which can vary from a few seconds to 1 hour, rinsing the hair is implemented.

[0183] According to a fourth embodiment, the three preceding embodiments are associated. For example, it is possible to implement step 1, a rinse, step 2, a rinse, drying the hair with a hair dryer, straightening the hair, then after a shampoo a step 1 is implemented again. It is also possible for example to implement step 2, a rinse, step 1, a rinse, drying the hair with a hair dryer, straightening the hair, then after shampooing a step 1 is implemented again. According to another embodiment, it is possible for example to implement step 1, a rinse, step 2, a rinse, step 1 again, a rinse followed by drying the hair with a hair dryer, straightening the hair, then after shampooing a step 1 is implemented again. According to a last embodiment, it is possible for example to implement step 1, a rinse, step 2, a rinse, step 1 again, a rinse followed by drying the hair with a hair dryer, straightening the hair. In the above embodiments, the rinses are preferably implemented with water.

[0184] Unless otherwise indicated, steps 1 and 2 can be carried out on dry or damp hair.

[0185] The compositions of steps 1) or 2) can be applied by any means, such as by means of a brush or a comb or even with the fingers.

[0186] Preferably, the compositions of steps 1 and 2 are left on the hair before rinsing for a leave-on time varying from 1 to 90 minutes, preferably from 1 to 45 minutes, more preferably from 1 to 30 minutes.

[0187] For the purposes of the present invention, the exposure time is the contact time of the composition on the hair. Preferably, the compositions are left to remain on the hair at room temperature. For the purposes of the present invention, the term "room temperature" means a temperature ranging from 20°C to 37°C.

[0188] Preferably, the hair dryer drying steps are carried out at a temperature below 100°C, preferably at a temperature ranging from 40 to 95°C.

[0189] Step 3) of smoothing / straightening is carried out at a temperature preferably greater than or equal to 110°C, preferably at a temperature ranging from 110°C to 280°C, more preferably ranging from 110°C to 250°C, better still ranging from 200°C to 250°C simultaneously or sequentially with a mechanical action.

[0190] For example, we can cite brushing using a brush and a hair dryer, a hair straightener, a hair straightener capable of generating steam at the time of treatment such as the Steampod© straightening tool which allows steam to be applied to the fibers and then straightened,

[0191] Preferably, step 3) is carried out with at least one hair straightener or a hair straightener capable of generating steam on the keratin fibers, at a temperature greater than or equal to 110°C.

[0192] The application of heat may vary, for example, from 5 to 30 minutes, preferably from 10 to 20 minutes.

[0193] When step 3) of smoothing / straightening is carried out using a straightening iron, it may be necessary to make several passes of the straightening iron, generally between 1 and 10 passes, preferably between 3 and 5 passes, each pass being carried out between 5 and 40 seconds. According to a particular embodiment with the straightening iron, the total duration of the treatment of the lock of hair is at most 1 minute.

[0194] The method according to the invention can be implemented on sensitized or non-sensitized hair.

[0195] In the method of the invention, steps 1) and 2) may be followed by a rinsing step and a hair drying step may be carried out before the straightening step 3).

[0196] Preferably, the hair straightening and / or straightening processes described above are implemented: 1. a step of applying a treatment composition comprising at least citric acid, at least arginine and at least betaine, the application time of the composition varying from 1 to 90 minutes 2. a step of applying a smoothing / straightening composition comprising at least one alkanolamine, preferably monoethanolamine, at least one compound chosen from taurine and its derivatives and at least one alkali or alkaline-earth metal hydroxide; with optionally the weight ratio between the alkanolamine and the compound chosen from taurine and its derivatives is greater than 1; and preferably, the application time of the composition varying from 5 to 45 minutes,

[0197] The invention also relates to a multi-compartment device comprising a first compartment comprising the treatment composition comprising at least one amino acid, preferably at least one carboxylic amino acid, preferably arginine, at least one optionally hydroxylated polycarboxylic acid, preferably citric acid, at least one osmolyte, preferably at least one compound of formula (I), preferably betaine or a betaine derivative, a second compartment comprising a smoothing / straightening composition comprising at least one alkanolamine, preferably monoethanolamine, at least one compound chosen from amino acids and their derivatives, preferably at least one compound chosen from sulfonic amino acids and their derivatives, preferably from taurine and its derivatives and at least one alkali or alkaline earth metal or ammonium hydroxide,preferably at least one alkali or alkaline earth metal hydroxide, preferably sodium hydroxide.

[0198] The following examples serve to illustrate the invention without, however, being limiting in nature.

[0199] Examples In the following examples, all quantities are indicated as a percentage by mass of active ingredient (AI) relative to the total weight of the composition (unless otherwise stated). Example 1 Step 1 Treatment Composition

[0200] [Tables 1] Ingredients Quantity in % MA Arginine 5 Betaine 2.5 Citric acid 6.1 Behentrimonium chloride 2.4 Fatty substance 7 amino silicone 0.7 Non-ionic surfactant 0.5 Water Qs 100 PH 3.8 Step 2 Smoothing Straightening Composition

[0201] [Tables2] Ingredients Quantity in % MA Taurine 3.75 Monoethanolamine 5.625 Sodium hydroxide 0.875 Cl3-16 isoalkane 5 Fatty alcohol 2.5 Dimethicone 0.1 Thickener 1.5 Non-ionic surfactants 4 Organic solvents 10 Water Qs 100 PH 10.7 Procedure 1

[0202] The treatment composition is applied to strands of natural curly hair (type IV curls) of Latin origin previously bleached. After a leave-on time of 30 min, the composition is then rinsed and then the smoothing / defrizzing composition is applied. After rinsing the smoothing composition, the hair is dried with a hair dryer and then the hair is straightened with a straightening iron at a temperature of 210°C and 230°C, after 5 passes of the iron at low speed to obtain a smoothing level of type 1 / 2. Procedure 2

[0203] The smoothing composition is applied to natural curly hair (type IV curls) of Latin origin previously bleached. After a setting time of 30 min, the composition is rinsed. After rinsing this composition, the treatment composition is applied and then rinsed. The hair is then dried with a hair dryer and then straightened with a straightening iron at a temperature of 210°C and 230°C, after 5 passes of the iron at low speed to obtain a smoothing level of type 1 / 2. Procedure 3

[0204] The smoothing composition is applied to natural curly hair (type IV curls) of Latin origin previously bleached. After a 30 min exposure time and rinsing of this composition, the hair is dried with a hair dryer then smoothed with a straightening iron at a temperature of 210°C and 230°C after 5 passes of the iron at low speed to obtain a smoothing level of type 1 / 2.

[0205] The hair is then washed with shampoo and the treatment composition is applied to damp hair. The hair is then dried with a hairdryer. Witness

[0206] The smoothing composition is applied to natural curly hair (type IV curls) of Latin origin previously bleached. After rinsing this composition, the hair is dried with a hair dryer and then smoothed with a straightening iron at a temperature of 210°C and 230°C, after 5 passes of the iron at low speed to obtain a smoothing level of type 1 / 2.

[0207] For each of these procedures, hair strengthening is evaluated using the differential scanning calorimetry (DSC) technique. This evaluation is representative of hair integrity in relation to the strength and / or repair of hair that has undergone various treatments that can damage the hair.

[0208] Measurement method: The differential scanning calorimetry (DSC) technique is known to those skilled in the art as a method which makes it possible to quantify the reinforcement of proteins in the cortex of keratin fibers (Kinetics of the changes imparted to the main structural components of human hair by thermal treatment, https: / / doi.Org / 10.1016 / j.tca.2018.01.014 & F.-J. Wortmann and H. Deutz, J. Appl. Polym Sci., 48, 137 (1993). The principle of the test is to measure the protein denaturation temperature. It is widely recognized that the higher the protein denaturation temperature, the better the integrity of the cortex proteins, which translates into reduced fiber breakage. The denaturation temperature is directly related to the binding density of the keratin proteins present in the cortex. Thus, the lower the denaturation temperature, the lower the protein bond density, the lower the disulfide bonds break, and the cortex is damaged. The device used to perform the measurements is a TA Instruments DSC Q20 reference device. This device measures the energy flow during heating of the sample.The temperature at which the energy flow is greatest represents the denaturation temperature (Td).

[0209] The results are reported in the table below

[0210] [Tables3] Operating mode Td °C / Smoothing 210°C Td °C / smoothing 230°C 1 133 133 2 148 144 3 147 147 Control 131 128 Bleached hair before smoothing treatment 140

[0211] These tests show that the method according to the invention allows significant smoothing of the hair, lasting over time while reducing damage to the hair and strengthening it. The method of the invention thus allows a reduction in hair breakage during the hair smoothing process.

Claims

Claims

1. A method of treating hair comprising 1) applying a treatment composition comprising a) one or more osmolytes; b) one or more amino acids, (c) one or more polycarboxylic acids, one of their salts or mixtures thereof, and 2) applying a hair straightening composition comprising: i) one or more alkanolamines, ii) one or more compounds selected from amino acids and their derivatives, and iii) one or more alkali metal, alkaline earth metal or ammonium hydroxides 3) a step of straightening / straightening the hair by mechanical means and heat.

2. Process according to the preceding claim in which the osmolyte a) is chosen from the compounds of formula (I): (R1)(R2)(R3)m-A+-CR4R5-(X)nY(I) in which: - R1, R2 and R3, identical or different, represent a C1-C4 alkyl group, preferably a C1-C2 alkyl group, preferably methyl; - A is N or S, preferably N; - m is 0 or 1; preferably 1 - n is 0 or 1; preferably 0 - X is a divalent, linear or branched, saturated or unsaturated alkyl group having from 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, optionally substituted by one or more groups chosen from a hydroxyl (-OH), an amino (-NH2); preferably ethylene or methylene; and - Y is -COO or -OSO3;preferably -COO - when A is S, then m=0 and R4 and R5, identical or different, represent a hydrogen atom or a saturated, unsaturated, linear, branched and / or cyclic hydrocarbon chain, in Cl-CIO, preferably in C1-C6, more preferably in C1-C4; optionally interrupted by one or more heteroatoms or groups chosen from -S-, -N=, -NH- or -C(NH)- and / or; optionally substituted by one or more groups chosen from a hydroxyl (-OH), an amino (-NH2), -SH, -COOH, or -CONH2; - when A is N and m = 0, then R4 represents a hydrogen atom or a saturated, linear or branched C1-C8 alkyl group, preferably a C1-C4 alkyl group; and R5 forms, with the nitrogen atom, a saturated heterocycle comprising from 5 to 8 members, preferably from 5 to 6 members, optionally substituted by one or more groups chosen from hydroxyls or C1-C4 alkyls; and - when A is N and m = 1, then R4 and R5, identical or different, represent a hydrogen atom or a saturated, unsaturated, linear, branched and / or cyclic C1-C10, preferably C1-C6, more preferably C1-C4 hydrocarbon chain;optionally interrupted by one or more heteroatoms or groups chosen from -S-, -N=, -NH- or -C(NH)- and / or optionally substituted by one or more groups chosen from hydroxyl (-OH), amino (-NH2), -SH, -COOH or -CONH2.;

3. A method according to any one of the preceding claims wherein the compounds of formula (I) are selected from valine betaine, glutamic acid betaine, glutamine betaine, trimethyllysine, glycine betaine (trimethylglycine), histidine betaine, alanine betaine, choline sulfate, pipecolic acid betaine, proline betaine, hydroxyproline betaine, tyrosine betaine, phenylalanine betaine, tryptophan betaine, leucine betaine, isoleucine betaine, dimethylsulfoniopropionate and mixtures thereof, preferably trimethylglycine.

4. Method according to any one of the preceding claims in which the osmolyte(s) a) represents from 0.05 to 10% by weight, preferably from 0.1 to 8% by weight, more preferably from 0.5 to 5% by weight, more preferably still from 0.8 to 4% by weight, better still from 1.0 to 3% by weight, relative to the total weight of the treatment composition.

5. Process according to any one of the preceding claims in which the polycarboxylic acid c) is chosen from the polycarboxylic acids of the following formula (II): 0 1 OH (II) / I w HO 0 sn Formula (II) in which: - n is an integer between 1 and 5, better between 1 and 3, preferably n=1 or 2, more preferably n=2; - A is a multivalent, saturated or unsaturated, linear, branched, cyclic, or even aromatic hydrocarbon group, comprising from 1 to 6 carbon atoms, preferably from 1 to 4 carbon atoms, optionally substituted by one or more hydroxyl groups (OH).

6. A method according to any one of the preceding claims in which the polycarboxylic acids are hydroxylated, and are preferably chosen from: - citric acid, malic acid; and tartaric acid alone or in a mixture, preferably citric acid.

7. Process according to any one of the preceding claims in which the polycarboxylic acid(s) c) are present in a total amount varying from 0.05 to 20% by weight, preferably from 0.1 to 15% by weight, more preferably from 1 to 10% by weight, even more preferably from 2 to 8% by weight, relative to the total weight of the treatment composition.

8. A method according to any one of the preceding claims wherein the amino acid b) of the treatment composition is a basic carboxylic amino acid preferably comprising a guanidine group, preferably -NH-C(NH)-NH2.

9. A method according to any preceding claim wherein the amino acid b) of the treatment composition is arginine.

10. Method according to any one of the preceding claims in which the amino acid(s) b) of the treatment composition are present in a total amount varying from 0.1% to 15% by weight, preferably from 1% to 10% by weight, preferentially from 2% to 8% by weight, more preferentially from 2.5% to 7.5% by weight, better still from 3 to 7% by weight, relative to the total weight of the treatment composition.

11. A method according to any preceding claim wherein the pH of the treatment composition is less than or equal to 5.

12. A method according to any preceding claim wherein the smoothing composition comprises one or more alkanolamines selected from monoethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, N,N-dimethylethanolamine, 2-amino-2-methyl-1-propanol, triisopropanolamine, 2-amino-2-methyl-1,3-propanediol, 3-amino-1,2-propanediol, 3-dimethylamino-1,2-propanediol, tris-hydroxymethylamino-methane and mixtures thereof, preferably the alkanolamine is monoethanolamine.

13. Method according to any one of the preceding claims, in which the smoothing composition comprises one or more alkanolamines in a total content ranging from 0.5 to 15% by weight, preferably from 1 to 10% by weight, preferentially from 2 to 8% by weight, better still from 3 to 7% by weight, relative to the total weight of the composition.

14. Method according to any one of the preceding claims, in which the smoothing composition comprises one or more amino acids chosen from sulfonic amino acids and their derivatives, preferably from taurine and its derivatives, preferentially from taurine and its salts, better still from taurine, sodium taurate, potassium taurate, magnesium taurate, and mixtures thereof, more preferentially the compound chosen from amino acids and their derivatives is taurine.

15. Method according to any one of the preceding claims, in which the smoothing composition comprises the amino acid(s) in a total content ranging from 0.5 to 15% by weight, preferably from 0.75 to 10% by weight, preferentially from 1 to 6% by weight, better still 2 to 5% by weight, relative to the total weight of the composition.

16. A method according to any one of the preceding claims, wherein the smoothing composition comprises one or more alkali metal, alkaline earth metal or ammonium hydroxides selected from alkali metal hydroxides, and mixtures thereof, preferably from sodium hydroxide, potassium hydroxide, and mixtures thereof.

17. A method according to any preceding claim, wherein the smoothing composition comprises the alkali metal, alkaline earth metal or ammonium hydroxide(s) in a total content ranging from 0.05 to 10% by weight, preferably from 0.1 to 5% by weight, preferentially from 0.5 to 3% by weight, better still from 0.6 to 2% by weight, relative to the total weight of the composition.

18. Method according to any one of the preceding claims, in which the smoothing composition is such that the weight ratio between the total content of alkanolamine(s) and the total content of compounds chosen from amino acids and their derivatives is between 1.1 and 5, preferably between 1.2 and 3, better still between 1.3 and 2.

19. Method according to any one of the preceding claims, in which step 3) of straightening is carried out using a straightening iron at a temperature between 110°C and 280°C, preferably between 110°C and 250°C, preferentially between 200°C and 250°C.

20. Method according to any one of the preceding claims, in which steps 1 and 2) are followed by a rinsing step and a hair drying step is carried out before the straightening step 3)

21. A multi-compartment device comprising a first compartment comprising the treatment composition comprising at least one amino acid, preferably at least one carboxylic amino acid, preferably arginine, at least one polycarboxylic acid, preferably hydroxylated such as citric acid, at least one osmolyte, preferably at least one compound of formula (I), preferably betaine or a betaine derivative, a second compartment comprising a smoothing / relaxing composition comprising at least one alkanolamine, preferably monoethanolamine, at least one compound chosen from amino acids and their derivatives, preferably at least one compound chosen from sulfonic amino acids and their derivatives, preferably from taurine and its derivatives and at least one alkali or alkaline earth metal or ammonium hydroxide, preferably at least one alkali or alkaline earth metal hydroxide,preferably sodium hydroxide,