MXPA06005589A

MXPA06005589A - Hair relaxing composition comprising at least one non-hydroxide polyguanidine

Info

Publication number: MXPA06005589A
Application number: MXPA/A/2006/005589A
Authority: MX
Inventors: Radisson Xavier; Malle Gerard; Blaise Christian
Original assignee: L'oreal Societe Anonyme
Priority date: 2005-05-17
Filing date: 2006-05-17
Publication date: 2007-04-10

Abstract

The present disclosure relates to a ready-to-use cosmetic composition for relaxing keratin fibers in a cosmetically acceptable medium comprising, as an active relaxing agent, a polyguanidine not belonging to the hydroxide family. The present disclosure is also directed to a multi-compartment kit comprising at least two compartments to be placed in contact to form the ready-to-use composition. Another aspect of the present disclosure relates to a process for using the presently disclosed composition.

Description

COMPOSITION OF HAIR PURIFICATION CONTAINING AT LEAST ONE HYDROXIDE-FREE MULTIGUANIDINE DESCRIPTION OF THE INVENTION The subject of the invention is a ready-to-use cosmetic straightening composition for the keratin fibers which contains, as an active curing agent, a multiguanidine which does not belong to the hydroxide family. It also contemplates a kit containing compartments for contacting and forming the composition ready for use, as well as a method using this composition. The term "mul tiguanidine that does not belong to the family of hydroxides" encompasses multiguanidines and their organic or mineral salts that do not contain in their chemical formula hydroxide ions. By "keratin fibers", it is understood according to the invention fibers of human or animal origin such as hair, hair, eyelashes, wool, angora, cashmere or skin. Although the invention is not limited to particular keratin fibers, however, reference will be made more particularly to hair. The term "straightening" encompasses, according to the invention, the straightening, smoothing or unraveling of Caucasian, Asian, North African or African hair. REF .: 173062 The term "multiguanidine that does not belong to the family of hydroxides" represents any organic compound that contains in its formula at least 2 times the following group: a carbon atom doubly bound to another nitrogen atom and simply attached to two other atoms of nitrogen and that does not contain hydroxide ions in its chemical formula. Advantageously, according to the invention, the muitiguanidines contain at least 2 times the guanidine group and preferably 2 or 3 times. In this text, the expression "between x% and y%" means that it goes from x to y%, with the limits x and y being included. Two techniques are used to obtain permanent hair deformation. They are based on a breakdown of the disulfide bonds present in the keratin (cystine): - The first consists, in a first time, in carrying out this opening of the disulfide bonds with the aid of a composition containing a reducing agent and then, preferably after having rinsed the hair, in reconstituting said disulfide bonds in a second time by applying the hair previously tensed by means of curlers or others, or to which it has been shaped or smoothed by other means, an oxidizing composition also called a fixative, in a manner that the desired form is given to the hair.

This technique allows indifferently to perform either the curling of the hair, either its straightening or de-straightening or its straightening. - The second is to perform an operation called lanthionization with the help of a composition containing a base belonging to the family of hydroxides. It leads to the substitution of the disulfide bonds (-CH2-S-S-CH2-) by lanthionine bonds (-CH2-SCH2-). This operation of lanthionization involves two consecutive chemical reactions: • The first reaction consists of a beta-elimination on cystine caused by a hydroxide ion, which leads to the breakdown of this union and the formation of dehydroalanine. cystine dehydroalanine The second reaction is a reaction of dehydroalanine with a thiol group. In effect, the double bond of the dehydroalanin formed is a reactive double bond. It can react with the thiol group of the cysteine residue that has been released to form a new union, called a bridge or union or lanthionine residue. dehydroalanine lanthionine With respect to the first technique that uses a reducing agent, this lanthionization technique does not need a fixation stage, since the formation of lanthionine bridges is irreversible. It is therefore carried out in a single step and indifferently allows the hair to be undulated, or to be straightened, or to be de-straightened, or smoothed. Nevertheless, it is mainly used for the straightening of naturally curly hair. For the first technique, the reducing compositions generally used for the first stage of a permanent or rolling operation contain thiols or sulfites or bisulfites as the reducing agent. These agents are generally used in essentially aqueous medium at concentrations of 0.5 to 1M to obtain a good opening of the disulfide bonds. Among the thiols, the commonly used are thioglycolic acid, cysteamine, glycerol monothioglycolate, thiolactic acid and cysteine. Thioglycolic acid is particularly effective in reducing the disulfide bonds of keratin at alkaline pH, especially in the form of ammonium thioglycolate, and is the most widely used permanent product ("hair waving"). It has been found, however, that thioglycolic acid must be used in a sufficiently basic medium (in practice, at a pH of 8.5 to 9.5) if a curling satisfactory in terms of intensity is to be obtained. In addition to the drawback of giving off an unpleasant odor that requires the use of more or less effective perfumes to mask the odors, the use of a thiol at alkaline pH also leads to degradations of the fiber and very particularly to the alteration of the artificial colorations. Sulfites or bisulfites are mainly used for the straightening. They have drawbacks similar to thiols, with less efficiency. Thiols and sulfites (or bisulfites) also have the disadvantage of having poor stability in aqueous solution. In general, the durability of the effects of deformations obtained with thiols and sulphites by reduction of disulfides and subsequent fixation, is judged to be much lower than that which can be obtained by the lanthionization technique. For the second technique, the compositions generally used to effect lanthionization contain, as a base, a hydroxide, such as sodium hydroxide, guanidinium hydroxide and lithium hydroxide. These active lanthionization agents that allow the disulfide bonds to be opened by a beta-elimination mechanism are generally employed in water-in-oil emulsion at concentrations of 0.4 to 0.6M, leaving them to react generally for 10 to 15 minutes at room temperature. Sodium hydroxide is the most commonly used agent. Guanidinium hydroxide is now the preferred compound for numerous compositions. These two hydroxides, sodium and guanidinium, are the two main agents used for the straightening or descreasing of naturally frizzy hair. They have several advantages over ammonium thioglycolate and sulphites, in particular an absence of unpleasant odor, the need for a single stage of use (shorter treatment duration) and a much more significant durability and efficacy of the deformation of the hair. However, these hydroxides have the major drawback of being caustic. This causticity affects the scalp causing irritations sometimes severe. It can be partially remedied by prior application on the scalp of a fat protective cream frequently called "base" or "base cream", the word "base" here not having the meaning of basic agent in the chemical sense. When the protective cream is associated with the hydroxide in a single composition, it is generally called "non-base" as opposed to the previous name. This "non-base" technology is preferred. The causticity of the hydroxides also affects the state of the hair, making it on the one hand rough to the touch and on the other much more fragile, being able to go this fragility until the collapse, even the rupture or also the dissolution of the hair if the treatment is prolonged. The hydroxides in some cases also cause discoloration of the natural hair color. The formulas that contain sodium hydroxide are generally called in English "lye relaxers" and those that do not contain it are called "no-lye relaxers". The main de-icing formulas called "no-lye" use guanidinium hydroxide. The guanidinium hydroxide is unstable, this is generated extemporaneously by mixing guanidine carbonate and a very poorly soluble hydroxide source, such as calcium hydroxide. The reaction between these two compounds leads to the formation of guanidinium hydroxide and calcium carbonate, which precipitates in the composition. The presence of this precipitate makes the final rinsing of the hair much more difficult and leaves on the hair and scalp mineral particles that give it a rough touch and a non-aesthetic appearance, which resembles films. The recent success of guanidinium hydroxide ("no-lye") over sodium hydroxide ("lye") seems to come from a better dermal efficiency and better skin tolerance. However, these technologies that use bases of the family of hydroxides turn out to be very aggressive for the hair and the scalp and demand a very strict control of the duration of application to avoid too strong irritations and the alteration of the hair, which can go to the break. This aggressiveness from the causticity of the hydroxides justifies that these compositions for the lanthionization of the hair are not used for the permanent ("hair waving"), but are reserved for the straightening ("hair straightening" or "hair relaxing"). In addition, hydroxides are known to be good hydrolysis agents of the amide functions (see, for example, March's Advanced Organic Chemistry, 5th ed., Wiley Interscience, New York, "Hydrolysis of Amides", pages 474 et seq.) , which lead, then, to the breaking of the peptide bonds by direct nucleophilic attack. It is thus likely that the alterations observed at the level of the hair and the keratin materials are in a broad sense due in large part to a partial hydrolysis of the amide bonds of the keratin. There is, therefore, a real need for the straightening of less aggressive compositions for hair and skin.

Several studies have been carried out with a view to remedying at the same time the disadvantages of reducing agents (first technique) and / or hydroxides (second technique). Thus, to replace thioglycolic acid, numerous reducing agents have been proposed, but thioglycolic acid in the form of ammonium thioglycolate is both the reference compound and the most widely used in cosmetic formulations, both for shaping and for straightening and smooth. In order to replace sodium or guanidinium hydroxides and to improve cutaneous tolerance, it has been proposed, in the patent US4530830, to use a composition based on quaternary ammonium hydroxides. However, these compositions have not given complete satisfaction, neither in terms of curling nor in terms of cosmetics. More generally, numerous publications describe the joint use of hydroxides that serve as an active agent of lanthionization, with certain additives that generally serve to protect the hair. Indeed, without using new active agents of lanthionization, the proposed improvements concern mainly the use of additives to improve the damage caused to the hair by the hydroxides. The following will be mentioned, as an example: - the application WO2002 / 003937, which describes a composition containing C3-C5 monosaccharides; the application WO2001 / 064171, which describes a composition containing complexing agents; - the patent US5641477, which describes a composition containing a hydrogenated starch hydrolyzate; - the application WO02085317, which describes a composition containing organic nucleophiles that react in the second stage with dehydroalanine formed with hydroxides to give rise to new bridges; - US Pat. No. 5,679,327, which describes a rolling composition that necessarily contains three active constituents for the straightening, namely, an alkaline hydroxide, an alkaline earth metal hydroxide and a nitrogenous organic base, each of the constituents in the composition being present in a proportion that would be insufficient to effect the straightening if they were used at this same concentration without the other two active agents. In other words, this patent describes a synergy between three constituents, these together leading to the straightening of the keratin fibers. If all these proposals lead to more or less marked improvements, they do not allow a sufficient reduction in the damages linked to the causticity of the hydroxides themselves.

With respect to the use of the hydroxides for the straightening, also disclosed in the patent US 4,524,787, a composition ready for use made from an almost "anhydrous" activating part consisting of an organic base in a solvent of polyhydroxylated alkane type and an aqueous part consisting of at least 20% water. However, this last type of composition does not yet give satisfaction, neither in terms of the quality of the straightening, nor in terms of mechanical and cosmetic properties of the hair that has undergone this treatment. As indicated above, the use of reducing agents leads to a mediocre durability for the straightening or de-creasing and the use of hydroxides, due to its causticity, limits its use in the field of the straightening. After important studies, it has now been discovered, in a totally surprising and unexpected way, that the first step of the lanthionization process could be carried out with multiguanidines which do not belong to the hydroxide family. In this way, excellent results are obtained in terms of straightening and of the cosmetic and mechanical properties of the hair. The subject of the present invention is a cosmetic composition containing, in a cosmetically acceptable medium, at least one muitiguanidine which does not belong to the family of hydroxides, the cosmetically acceptable medium and muitiguanidine being selected in such a way that the multiguanidine which does not belong to the family of hydroxides react on the cystines of the keratin fibers by a beta-elimination reaction that produces dehydroalanine and which leads to the formation of lanthionine, to relax the keratin fibers in less than 60 minutes. Advantageously, the duration of the rolling is less than 40 minutes and more advantageously less than 30 minutes. By "multiguanidines not belonging to the family of hydroxides" usable as active agents of beta-elimination leading to lanthionization, is meant any organic compound containing in its formula at least 2 times the following group: a double-bonded carbon atom to another nitrogen atom and simply attached to two other nitrogen atoms; It does not contain hydroxide ions in its formula and it is capable of accepting a proton. The multiguanidines according to the invention are mainly selected from the group of compounds corresponding to the following general formula (I): (i) where: • Rl, R'l, R2, R'2, R3, R'3, R4 and R'4, identical or different, represent a radical selected from: - a hydrogen atom; - a saturated or unsaturated Cl a C6 alkyl group, linear, such as, for example, methyl or ethyl, or branched, such as, for example, isopropyl or tert-butyl, or also cyclic, such as, for example, cyclopentyl or cyclohexyl, said alkyl group being optionally substituted by the following radical: where R5, R '5, R6 and R' 6 have the same meanings as the radicals R1 to R4 previously designated; • R1 and R2 and / or R3 and R4 can also together form a divalent radical (CH2) 2 or (CH2) 3 or CH = CH; A represents a linear or cyclic, saturated or unsaturated C2 to C12 divalent hydrocarbon radical, which may be optionally interrupted by one or more groups such as imino, carboxamido, sulfoxide and sulfone and / or by: - one or more heteroatoms selected from sulfur, oxygen, nitrogen and silicon and optionally substituted by: a linear or branched Cl to C4 alkyl radical optionally interrupted by one or more heteroatoms such as those defined above and optionally substituted by the following radical: where R5, R'5, R6 and R '6 have the same meanings as the Rl to R' 4 radicals designated above. The compounds of general formula (I) are prepared according to the following reaction schemes: Reaction Scheme 1: The Vislmeyer 1 salt (prepared by the action of phosgene or a substitute such as oxalyl chloride or oxychloride of phosphorus on tetraalkylurea) is reacted with diamine 2 (or triamine 3) in a polar aprotic solvent, such as acetonitrile, in the presence of a tertiary organic base, such as, for example, triethylamine, to obtain the compounds of formula (I ).

Reaction scheme 2: The dihalogenated derivative 4 is made to react with a large excess of tetraalkylguanidine 5 at a temperature close to 100 ° C. The excess tetraalkylguanidine is removed by evaporation under reduced pressure and the residue is treated with a base such as, for example, sodium ethylate in ethanol.

The salt is removed by filtration and the expected derivative of formula (I) is then obtained and purified generally by distillation under reduced pressure.

Useful reference may be made to the operating modes described in the following references: -1) Z. anorg. Allg. Chem. , 2000, 626, 1583-1590; -2) Inorg. Chem. 2001, 40, 6964-6971; -3) J. Org. Chem. 2003, 68, 8790-8797; -4) J. Chem. Soc. , Dalton Trans. , 2000, 3473-3479. Preferred compounds of formula (I) are the following: N, N-bis (1,3-dimethyl-2-imidazolidinylidene) -1,2-benzenediamine (RN: 774610-65-0) , N- [bis (dimethylamino) ethylene] -3- (dimethylamino) -5-imino-2-methyl-2,4,6-9-tetraazaeicosan-20-imidamide (RN: 791543-84-5), N, '-bis (tetrahydro-1,3-dimethyl-2 (1H) -pyrimidinyl-deno) -l, 3-propanediamine (RN: 752232-69-2), 1, 1', ", 1 '' '~ [ 1-propanediylbis (nitrilomethane-trail)] tetrakispiperidine (RN: 752232-68-1), - poly (oxy-1,2-ethanediyl) -α- [2- [(1,3-dimethyl-2-imidazolium-dinylidene) amino] ] ethyl] -? - [2- [(1,3-dimethyl-2-imidazo-lidinylidene) amino] ethoxy] (RN: 742679-23-8), N ", N '' '' '-1,2 -etanodiilbis [?,?,? ' ,? ' -tetrakis- (1- ethylethyl) uanidine (R ?: 676488-06-5),?,? ' -bis (1,3-dihydro-l, 3-dimethyl-2H-imidazol-2-ylidene) -1,8-naphthalenediamine (RN: 634192-99-7), -?,? ' -bis (1,3-dimethyl-2-imidazolidinylidene) -1,8-naphthalendia ina (R ?: 501931-38-0), -? ",? '' '' '-l, 8-biphenylenediylbis [? ?,? ' ,? ' -tetramethylguanidine] (R ?: 495408-66-7), -? ",? "'' '-benzo [c] phenanthrene-1, 12-diylbis [?,?,?' ,? ' - tetramethylguanidine] (RN: 495408-58-7), -? ",? '' '' '-4, 5-phenantrenodiilbis [?,?,?' ,? ' -tetramethylguanidine] (R ?: 495408-50-9), -? ",? '' '' - (9,10-dihydro-4,5-phenanthrenodiyl) bis- [?,?,? ' ,? '- tetramethylguanidine] (R ?: 495408-44-1), -? ",? '' '' '-1,2-phenylenebis [?,?,? ' ,? ' -tetramethylguanidine] (R ?: 495408-35-0), -hydrochloride of? ",? '' '' '-1, 8-naphthalenediylbis- [?,?,?' ,? '- tetramethylguanidine] (R ?: 443892-20-4), - ",? '' '' '-9H-flurene-4,5-diylbis- [?,?,?' ,? '- tetramethylguanidine] (RN: 443892-12-4), -?' - (tetrahydro-1,3-dimethyl-2- (1H) -pyrimidinylidene) -?,? - bis [2- [(tetrahydro-1,3-dimethyl-2 (1H) -pyrimidinidene) amino ] ethyl] -1,2-ethanediamine (R ?: 395640-62-7), -? ",? ' '' '',? ' '""' '- (nitrilotri-2, l-ethanediyl) tris- [?,?,?' ,? '- tetramethylguanidine] (R ?: 368866-05-1), - N ", N' '' '' - [2- [[[(bis (dimethylamino) methylene] -amino] -methyl] -2- methyl-l, 3-propanediyl] bis [N, N, N ', N' -tetramethylguanidine] (RN: 289474-30-2), -? ",? '" "- (2, 2-dimethyl-l, 3-propanediyl) -bis- [?,?,? ',?' -tetramethylguanidine] (RN: 289474-29-9), -? ",?" "'-1,3-propanediylbis [?,?,? ',?' -tetramethylguanidine] (R ?: 289474-28-8), -? "," '' '' '-1,2-ethanediylbis [?,?,?',? '-tetramethylguanidine] (R? : 289474-25-5), -?,? '-bis (1,3-dihydro-l, 3-dimethyl-2H-imidazol-2-ylidene) -1, 2-ethanediamine (R ?: 216873-26- 6), -?,? '' '-1,2-ethanediylbis [?',? ',? ",?" -diethylguanidine] (R ?: 211869-99-7), -? ",' '' ' '- [(methylimino) di-3, 1-propanediyl] bis] -?,?,?',? '-tetramethylguanidine] (R ?: 196405-86-4), -? ",?' '<; > • - [oxobis (2, l-ethanediyloxy-3, 1-propane-diyl)] bis [?,?,? ' ,? ' -tetramethylguanidine] (RN: 190442-53-6), -? ",? '' '' '- [[1, 1,3, 3-tetramethyl-l, 3-disiloxanediyl] di-3, 1-propanediyl] bis [?,?,? ' ,? ' -tetramethylguanidine] (R ?: 175989-14-7), -? ",? "" '- [[1,3-dimethyl-l, 3-bis (trimethyl-silyl) oxy] -1,3-disyloxanediyl] di-3,1-propanediyl] bis- [?,?,?' ,? ' -tetramethylguanidine] (RN: 172283-48-6), -?,? "-1, 6-hexanediylbis [? ' - [bis (dimethylamino) methylene-rea (RN: 157362-45-3), [bis (dimethylamino) methylene] - [3- [[[[[bis (dimethylamino) methylene] amino] carbonyl] amino] methyl] - 3,5, 5-tri-methylcyclohexyl] urea (RN: 157362-44-2), - N ", N '" "- [i, 1-biphenyl] -2, 2'-diilbis- [N, N , N ', N' -tetramethylguanidine] (RN: 144576-63-6), -4,4'-sulphonylbis [N- (1,3-dimethyl-2-imidazolidinyl-deno) benzenamine (RN: 129346-76- 5), -N, N'-bis (1,3-dimethyl-2-imidazolidinylidene) -2,8-dibenzothiophenodiamine-5, 5-dioxide (RN: 128169-35-7), -N, N'-bis (1,3-dimethyl-2-imidazolidinylidene) -4,6-dibenzothiophenediamine-5, 5-dioxide (RN: 127330-56-7), -N, N'-bis (1,3-dimethyl-2-imidazolidinylidene) ) -1,2-ethanediamine (RN: 126620-51-7), -N ", N '' '' '-1,3-phenylenebis [N, N, N', N '-tetramethyl-guanidine] (RN) : 121648-84-8), -N, N'-bis [bis (dimethylamino) methylene] butanediamine (RN: 114491-72-4), -N ", N '' '' '-1,4-phenylenebis [ N, N, N ', N' -tetramethylguanidine] (RN 113551-45-4), -N ", N '' '' '- [[1,3-dimethyl-l- [(pentamethyldi-siloxanyl) -oxi] -3- [(trimethylsilyl) oxy] -1,3-disyloxane-diyl]] di-3,1-propanediyl] bis [N, N, N ', N' -tetramethylguanidi- Na] (RN: 109956-31-2), -N, N "-bis [(dimethylamino) - (dipentylamino) methylene] -1,4-piperazineadicarboximidamide (R ?: 97983-93-2), -N, N "-bis [(dimethylamino) - (hexylpropylamino) methylene] -1,4-piperazinadicarboximidamide (RN: 97983-92-1), -N, N" -bis [(hexylmethylamino) -methylpropyl-amino) methylene] -1, 4-piperazinadicarboximidamide (RN: 97983-91-0), - N, N "-bis [(butylmethylamino) - (hexylmethylamino) methylene] -1, -piperazinadicarboximidamide (RN: 97983-90-9), -N, N" -bis [(dimethylamino) - (heptylmethylamino) methylene] -1,4-piperazinadicarboximidamide (RN: 97963-91-2), -N ", N" "'- [(1, 1, 3,3-tetramethoxy-1) , 3-disiloxanediyl) di-3, 1-propanediyl] bis [N, N, N7, N '-tetramethylguanidine] (RN: 69755-28-8), -N ", N' '' '' -l , 6-hexanediylbis [N, N, N ', N' -tetramethylguanidine] (RN: 64933-93-3), -N ", N '' '" - (methylene-4,1-phenylene) bis [N, N, N ', N' -tetramethylguanidine] (RN: 57414-23-0), -N, N "- (methylphenylene) bis [N '- [bis (dimethylamino) -methylene] urea (RN) : 39529-23-2) and -2.2'- (sulfonyldiethylene) bis [1,1,3,3-tetramethylguanidine] (RN: 13998-89-5). The compounds of general formula (I) which are more particularly preferred are the following: N- [bis (dimethylamino) methylene] -3- (dimethylamino) -5-imino-2-methyl-2,4,6, 19-tetraazaeicosan-20 -imidamide (RN: 791543-84-5), - N, N, '-bis (tetrahydro-1,3-dimethyl-2 (1H) -pyrimidinylidene) -1,3-propanediamine (RN: 752232-69 -2), -poly (oxy-1, 2-ethanediyl) -a- [2- [(1,3-dimethyl-2-imidazo-lidinylidene) amino] ethyl] -? - [2- [(1, 3 -dimethyl-2-imidazoli ~ dinylidene) amino] ethoxy] (RN: 742679-23-8), -N ", N '' '' '-1,2-ethanediylbis [N, N, N', N '- tetrakis (1-methylethyl) uanidine (RN: 676488-06-5), -N, N '-bis (1,3-dihydro-l, 3-dimethyl-2H-imidazol-2-yl-dene) -1, 8-naphthalenediamine (RN: 634192-99-7), -N, N'-bis (1,3-dimethyl-2-imidazolidinylidene) -1,8-naphthalene diamine (RN: 501931-38-0), N ", N '' '' '-1,2-phenylenebis [N, N, N', N '-tetramethylguanidine] (RN: 495408-35-0), N ", N' '' '' hydrochloride -1, 8 -naphthalene-diilbis- [N, N, N ', N' -tetramethylguanidine] (RN: 443892-20-4), - N ", N '" ", N" '"" "- (nitrilotri-2, l-ethanediyl) tris- [N, N, N', N '-tetramethylguanidine] (RN: 368866-05-1), -N",' '' '' - [2- [[(bis (dimethylamino) methylene] amino] ethyl] -2-methyl-1,3-propanediyl] bis [N, N, N ', N' -tetramethylguanidine] (RN: 289474-30 -2), - N ", N '' '' '- (2,2-dimethyl-l, 3-propanediyl) -bis- [N, N, N', N '-tetramethylguanidine] (RN: 289474-29 -9), N ", N '' '' '-1,3-propanediylbis [N, N, N', N '-tetramethylguanidine] (RN: 289474-28-8), N, N' -bis (1, 3- dihydro-l, 3-dimethyl-2H-imidazol-2-ylidene) -1, 2-ethanediamine (RN: 216873-26-6), - N, N '"-l, 2-ethanediylbis [N', N ' , N ", N" -diethylguanidine] (RN: 211869-99-7),? ",? ' '' '' [(methylimino) di-3, 1-propanediyl] -bis- [?,?,? ' ,? ' -tetramethylguanidine] (R ?: 196405-86-4), -? ",? ' '' '' - [oxybis (2, l-ethanediyloxy-3, 'l-propanediyl)] bis [?,?,?' ,? ' -tetramethylguanidine] (R ?: 190442-53-6,? ",? '' '' '- [[1,1,3,3-tetramethyl-l, 3-disiloxanediyl] di-3, l-propanediyl] bis [?,?,? ',?' -tetramethylguanidine] (R ?: 175989-14-7), -?,? "- 1,6-hexanediylbis [? '- bis (dimethylamino) methyleneurea (R ?: 157362- 45-3),? ",? '' '' '- [1,1'-biphenyl] -2, 2'-diilbis- [?,?,?',? '- tetramethylguanidine] (R ?: 144576- 63-6), -?,? '-bis (1,3-dimethyl-2-imidazolidinylidene) -1, 2-ethanediamine (RN: 126620-51-7),? ",?' '' '' -1 , 4-phenylenebis [?,?,? ',?' -tetramethylguanidine] (R ?: 113551-45-4),? ",? '' '' '- [(1, 1, 3,3-tetramethoxy-) l, 3-disi-loxanediyl) -di-3, 1-propanediyl] bis [?,?,? ',?' -tetramethylguanidine] (R ?: 69755-28-8),? ",?" '' '~ 1, 6-hexanediylbis [?,?,?',? '-tetramethylguanidine] (R ?: 64933-93-3) and 2,2'- (sulfonyldiethylene) bis [1, 1,3,3 -tetra-methylguanidine] (R ?: 13998-89-5).

The invention also relates to the new compounds of general formula (II): i ") where: • Rl, R'l, R2, R'2, R3, R'3, R4 and R'4, identical or different, represent a group selected from: - a hydrogen atom and - a methyl radical , ethyl, propyl or isopropyl, Rl and R2 and / or R3 and R4 can also together form a divalent radical (CH2) 2 or (CH2) 3 or CH = CH; • B represents a radical selected from: • when R '1 = R' 2 = R '3 = R' = CH3 and when R1 / R2 and R3 / R4 respectively form the divalent radical (CH2) 2, B also represents a divalent radical (CH2) 2 or (CH2) 5 or (CH2) 6 or a radical: • when R '1 = R' 2 = R '3 = R' 4 = CH3 and when R1 / R2 and R3 / R4 respectively form the divalent radical (CH2) 3, B represents (CH2) 2 or (CH2) 3 or (CH2) 4 or (CH2) 5 or (CH2) 6 or a radical: • when R '1 = R' 2 = R '3 = R' = CH3 and when R1 / R2 and R3 / R4 form respectively and simultaneously the divalent radical CH = CH, B represents (CH2) 3 or (CH2) 4 or (CH2) 5 or (CH2) 6 or a radical: • when Rl, R'l, R2, R'2, R3, R'3, R4 and RM represent an ethyl or isopropyl radical, B represents a radical (CH2) 3 or (CH2) 4 or (CH2) 5 or ( CH2) 6 or a radical: • when Rl, R'l, R2, R'2, R3, R'3, R4 and RM represent a methyl radical, B represents a radical (CH2) 4 or (CH2) 5. The preferred compounds of general formula (II) are: • N, N, N ', N'-tetraisopropyl-N "- [3- (N', N ', N", N "-tetraiso-propylguanidino) propyl] guanidine, • N, N, N', N ' ~ tetraisopropyl ~ N "- [4- (N ', N', N", N "-tetraiso-propylguanidino) butyl] guanidine, • N, N, N ', N'-tetraisopropyl-N" - [5- ( N ', N', N ", N" -tetraiso-propylguanidino) pentyl] guanidine, • N, N, N ', N'-tetraisopropyl-N "- [6- (N', N ', N", N "-tetraiso-propylguanidino) hexyl] guanidine, • N, N, N ', N'-tetraisopropyl-N" - (3. {methyl- [3- (N', N ', N ", N" - tetraisopropylguanidino) propyl] amino.}. propyl) guanidine, • N, N, N ', N'-tetraethyl-N "- [3- (N', N ', N", N "-tetraethylgua-nidino] propyl] guanidine, • N, N, N ', N'-tetraethyl-N "- [4- (N', N ', N", N "-tetraethylgua-nidino) butyl] guanidine, • N, N, N', N'-tetraethyl-N "- [5- (N ', N', N", N "-tetraethylgua-nidino) pentyl] guanidine, • N, N, N ', N'-tetraethyl-N" - [6 - (N ', N', N ", N" -tetraethylgandine) hexyl] guanidine, • N, N, N ', N' -tetraethyl-N "- (3-. {Methyl- [3- ( N ', N', N ", N" - tetraisopropylguanidino) propyl] amino.}. Propyl) guanidine, • N, N'-bis (1,3-dimethylimidazolidin-2-ylidene) butane-l, 4-diamine, • N, N'-bis (1,3-dimethylimidazolidin-2-ylidene) pentane-l, 5-diamine , • N, N'-bis (1,3-dimethylimidazolidin-2-ylidens) hexane-l, 6-diamine, • N- (1,3-dimethylimidazolidin-2-ylidene) ~ N '- [3- (1 , 3-dimethyldimidazolidin-2-ylideneamino) propyl] -N'-methylpropane-1,3-diamine, • N, N'-bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) pro -pane-1,3-diamine, • N, N'-bis (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidene) butane-1,4-diamine, • N, N'-bis (1 , 3-dimethyl-l, 3-dihydroimidazol-2-ylidene) pentane-1,5-diamine, • N, N'-bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) he-xano -1, 6-diamine, • N- (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) -N '- [3- (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidenamino ) propyl] -N '-methylpropane-1,3-diamine, • N, N' -bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) ethane-1,2-diamine, • N, N'-bis (1 , 3-dimethyltetarhydropyrimidin-2-ylidene) propane-1,3-diamine, • N, N'-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) butane-1, -diamine, • N, N'-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) entano-1,5-diamine, •?,? '-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) hexane-1,6-diamine, •? - (1,3-dimethyltetrahydropyrimidin-2-ylidene) -?' - [3- (1, 3-dimethyltetrahydropyrimidin-2-ylidenamino) propyl] -? '-methylpropane-1,3-diamine, •?,?,?',? '-tetramethyl-? "- [4- (?',? ',?" ,? "-tetra-ethyl-guanidino) butyl] guanidine, •?,?,? ',?' -tetramethyl-?" - [5- (? ',?', W,? "-tetramethyl-guanidino) pentyl] guanidine, • N,?,? ',?' -tetramethyl-? "- [3- (? ',?',?",? "- tetramethyl-guanidino ethyl) cyclohexylmethyl] guanidine, •?,?,? ' ,? '- tetraethyl -? "- [3- (?',? ',?",? "-tetraethylgandidinomethyl) cyclohexylmethyl] guanidine, •?,?,?' ,? ' -tetrapropyl -? "- [3- (? ',?',?",? "- tetrapropyl-guanidinomethyl) cyclohexylmethyl] guanidine, •?,?,? ' , N '-tetraisopropyl-? "- [3- (?',? '-?",? "-tetraiso-propylguanidinomethyl) cyclohexylmethyl] guanidine, • N, N, N', N '-tetraethyl-N" - [ 3- (N ', N', N ", N" -tetraethylgua-nidinomethyl) benzyl] guanidine, • N, N, N ', N'-tetrapropyl-N "- [3- (N', N ', W , N "-tetrapropyl-guanidinomethyl) benzyl] guanidine, • N, N, N ', N' -tetraisopropyl-N" -3- (N ', N', N ", N" -tetraiso-propylguanidinomethyl) benzyl] guanidine , • N "- [2,2-dimethyl-3- (N ', N', N", N "-tetraethylguanidino) -propyl] -N, N, N ', N' -tetraethylguanidine, • N" - [ 2,2-dimethyl-3- (N ', N', N ", N" -tetrapropylguanidino) -propyl] -N, N, N ', N' -tetrapropylguanidine, • N "- [2,2-dimethyl- 3- (N ', N', N ", N" -tetraisopropylguanidi-no) propyl] -N, N, N ', N' -tetraisopropylguanidine, • N, N, N ', N.' -tetramethyl-N "-. {2- [2- (N ', N', N", N "-tetra-ethyl-guanidino) ethoxy] ethyl} guanidine, • N, N, N ', N' -tetraethyl-N "-. { 2- [2- (N ', N', N ", N" -tetraethylguanidino) ethoxy] ethyl} guanidine, • N, N, N ', N' -tetrapropyl-N "-. {2- [2- (N ', N', N", N "-tetrapropylguanidino) ethoxy] ethyl} guanidine, • N, N, N ', N'-tetraisopropyl-N "-. { 2- [2- (N ', N', N ", N" -tetra-isopropylguanidino) ethoxy] ethyl} guanidine, • N, N, N ', N' -tetramethyl-N "-. {2- [2- (N ', N', N", N "-tetramethyl-guanidino) ethylsulfanyl] ethyl} guanidine , • N, N, N ', N' -tetraethyl-N "-. { 2- [2- (N ', N', N ", N" -tetraethylguanidino) ethylsulfanyl] ethyl} guanidine, • N, N, N ', N'-tetrapropyl-N "-. {2- [2- (N', N ', N", N "-tetrapro-pylguanidino) ethylsulfanyl] ethyl} guanidine , • N, N, N ', N' -tetraisopropyl-N "-. { 2- [2- (N ', N', N ", N" -tetra-isopropylguanidino) ethylsulfanyl] ethyl} guanidine, • N, N, N ', N'-tetramethyl-N "-. {2- [2- (N', N ', N", N "-tetramethyl-guanidino) ethyldisulfanyl] ethyl} guanidine , • N, N, N ', N' -tetraethyl-N "-. { 2- [2- (N ', N', N ", N" -tetraethyl-guanidino) ethyldisulfanyl] ethyl} guanidine, • N, N, N ', N' -tetrapropyl-N "-. {2- [2- (N ', N', N", N "-tetrapro-pylguanidino) ethyldisulfanyl] ethyl} guanidine , • N, N, N ', N' -tetraisopropyl-N "-. { 2- [2- (N ', N', N ", N" -tetra-isopropylguanidino) ethyldisulfanyl] ethyl} guanidine, • N, N, N ', N' -tetramethyl-N "- [2-methyl-5- (N ', N', N", N "-tetra-methylguanidino) pentyl] guanidine, • N, N , N ', N' -tetraethyl-N "- [2-methyl-5- (N ', N', N", N "-tetra-ethylguanidino) pentyl] guanidine, • N, N, N ', N' -tetrapropyl-N "- {2-methyl-5- (N ', N', N", N "-tetra-propylguanidino) pentyl] guanidine, • N, N, N ', N' -tetraisopropyl-N "- [2-methyl-5- (N ', N', N", N "-te-traisopropylguanidino) pentyl} guanidine, • N, N, N ', N' -tetramethyl-N "- { 3- [3- (N ', N', N", N "-tetramethyl-guanidino) propoxy] propyl.} guanidine , • N, N, N ', N' -tetraethyl-N "-. { 3- [3- (N ', N', N ", N" -tetraethyl-guanidino) propoxy] propyl} guanidine, • N, N, N ', N' -tetrapropyl-? "- { 3- [3- (? ',?',?",? "-tetrapro-pilguanidino) propoxy] propyl.} guanidine , • N,?,? ' ,? ' -tetraisopropyl -? "-. { 3- [3- (? ',?',? ",?" -tetra-isopropylguanidino) propoxy] propyl} guanidine, •?, N,? ' ,? ' -tetramethyl-? "- (2- { methyl [2- (? ',?',?",? "- tetra-methylguanidino) ethyl] amino.} ethyl) uanidine, •?,?,? ' ,? ' -tetraethyl-? "- (2- { methyl [2- (N ',?',?",? "-tetra-ethylguanidino) ethyl] amino.} ethyl) guanidine, •?,?,? ' ,? ' -tetrapropyl-? "- (2- {methyl [2- (? ',?',?",? "- te-trapro-pylguanidino) ethyl] amino.} ethyl) guanidine, •?,?,? ' ,? ' -tetraisopropyl-? "- (2- { methyl [2- (? ',?',?",? "- tetraisopropylguanidino) ethyl] amino.} ethyl) guanidine, •?,?,? ' ,? ' -tetramethyl-? "- (2- { 2- [2- (? ',?',?",? "- tetra-methylguanidino) ethoxy] ethoxy.} ethyl) guanidine, •?,?,? ' ,? '-tetraethyl-? "- (2- { 2- [2- (?',? ',?",? "-tetra-ethylguanidino) ethoxy] ethoxy.} ethyl) guanidine, •?, ?,? ' , N '-tetrapropyl-? "- (2- { 2- [2- (?',? ',?",? "- tetra-propylguanidino) ethoxy] ethoxy.} Ethyl) guanidine, •?, ?,? ' , N '-tetraisopropyl-? "- (2- { 2- [2- (?',? ',?",? "- te-traisopropylguanidino) ethoxy] ethoxy.} Ethyl) guanidine, • 2- . { 3- [(1,3-dimethylimidazolidin-2-ylidenamino) methyl] cyclohexylmethylimino} -1, 3-dimethylimidazolidine, • 2-. { 3- [(1,3-dimethylimidazolidin-2-ylidenamino) methyl] benzylamino} -!, 3-dimethylimidazolidine, • N, N'-bis (1,3-dimethylimidazolidin-2-ylidene) -2,2-dimethylpropane-1,3-diamine, • 2-. { 2- [2- (1, 3-dimethylimidazolidin-2-ylidenamino) ethylsulphonyl] ethylimino} -l, 3-dimethylimidazolidine, • 2-. { 2- [2- (1, 3-dimethylimidazolidin-2-ylidenamino) ethyldisulfanyl] ethylimino} - !, 3-dimethylimidazolidine, • Nl, N5-bis (1,3-dimethylimidazolidin-2-ylidene) -2-methyl-pentane-1,5-diamine, • N- (1,3-dimethylimidazolidin-2-ylidene ) -N '- [2- (1,3-dimethyladimidazolidin-2-ylidenamino) ethyl] -N'-methylethane-1,2-diamine, • Nl, N5-bis (1,3-dimethyl-1, 3-dihydroimidazol-2-ylidene) -2-methylpentane-1,5-diamine, • N- (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) -N '- [2- (1, 3 -dimethyl-1,3-dihydroimidazol-2-ylidenamino) ethyl] -N'-methylethane-1,2-diamine, • 2-. { 3- [(1,3-dimethyl-l, 3-dihydroimidazol-2-ylidenamino) -methyl] cyclohexylmethylimino} -1, 3-dimethyl-2,3-dihydro-1H-imidazole, • N, N'-bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) -2,2-dimethylpropane-1, 3-diamine, • 2-. { 3- [(1,3-dimethyl-l, 3-dihydroimidazol-2-ylidenamino) -methyl] benzylimino} -1, 3-dimethyl-2,3-dihydro-lH-imidazole, • 2- . { 2- [2- (1, 3-dimethyl-1,3-dihydroimidazol-2-ylidenamino) ethyldisulfanyl] ethylimino} -1, 3-dimethyl-2,3-dihydro-lH-imidazole, • 2-. { 2- [2- (1, 3-dimethyl-1,3-dihydroimidazol-2-ylidenami-no) ethylsulfanyl] ethylimino} -!, 3-dimethyl-2,3-dihydro-lH-imidazole, • Nl, N5-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) -2-methylpentane-1,5-diamine, • N- (1 , 3-dimethyltetrahydropyrimidin-2-ylidene) -N '- [2- (1,3-dimethyltetrahydropyrimidin-2-ylidenamino) ethyl] -N'-methylethane-1,2-diamine, • 2-. { 3- [(1,3-dimethyltetrahydropyrimidin-2-ylidenamino) ethyl] cyclohexylmethylimino} -1, 3-dimethylhecahydropyrimidine, • N, N'-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) -2,2-dimethylpropane-1,3-diamine, • 2-. { 3- [(1,3-dimethyltetrahydropyrimidin-2-ylidenamino) methyl] benzylimino} -1, 3-dimethylhexahydropyrimidine, • 2-. { 2- [2- (1,3-dimethyltetrahydropyrimidin-2-ylidenamino) -ethyldisulfanyl] ethylimino} -1, 3-dimethylhexahydropyrimidine and • 2- . { 2- [2- (1, 3-dimethyltetrahydropyrimidin-2-ylidenamino) -ethylsulfanyl] ethylimino} -1, 3-dimethylhexahydropyrimidine. Particularly preferred compounds of general formula (II) are: • N, N, N ', N'-tetraisopropyl-N "- [3- (N', N ', N", N "-tetraiso-propylguanidino) propyl] guanidine, • N, N, N ', N' -tetraisopropyl-N "- [4- (N ', N', N", N "-tetraiso-propylguanidino) butyl] guanidine, • N, N, N ', N '-tetraethyl-N "- [3- (N', N ', N", N "-tetraethylgua-nidino) propyl] guanidine, • N, N, N', N'-tetraethyl-N" - [4 - (N ', N', N ", N" -tetraethylguandine) butyl] guanidine, • N, N'-bis (1,3-dimethylimidazolidin-2-ylidene) butane-1,4-diamine, • N - (1,3-dimethylimidazolidin-2-ylidene) -N '- [3- (1,3-dime-tilimidazolidin-2-ylidenamino) propyl] -N' -methylpropane-1,3-di-mina, • N, N '-bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) propane-1,3-diamine, • N, N' -bis (1,3-dimethyl-1,3-dihydroimidazole-2) -ylidene) bu-tano-1,4-diamine, • N- (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidene) -N '- [3- (1,3-dimethyl-l, 3 -dihydroimidazol-2-ylidenamino) propyl] - N 'methylpropane-1,3-diamine, • N, N' -bis (1 , 3-dimethyltetrahydropyrimidin-2-ylidene) ethane-1,2-diamine, • N, '-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) propane-1,3-diamine, • N, N, N', N '-tetramethyl-N "- [4- (N', N ',", N "-tetra-ethylgua-nidino) butyl] guanidine, • N, N, N', N '-tetramethyl-N" - [3 - (N ', N', N ", N" -tetramethyl-nidinomethyl) cyclohexylmethyl] guanidine, • N, N, N ', N' -tetraethyl-N "- [3- (N ', N', N" , N "~ tetraethylguane-nidinomethyl) benzyl] guanidine, • N" - [2,2-dimethyl-3- (N ', N', N ", N" -tetraethylguanidino) propyl] -N, N, N ', N '-tetraethylguanidine, • N, N, N', N '-tetramethyl-N "-. { 2- [2- (N ', N', N ", N" -tetramethylguanidino) ethoxy] ethyl} guanidine, • N, N, N ', N' -tetramethyl-N "-. {2- [2- (N ', N', N", N "-tetramethyl-guanidino) ethylsulfyl] ethyl]. guanidine, • N, N, N ', N' -tetramethyl-N "-. { 2- [2- (N ', N', N ", N" -tetramethylguanidino) ethyldisulfanyl] ethyl} guanidine, • N, N, N ', N' -tetramethyl-N "- [2-methyl-5- (N ', N', N", N "-tetramethylguanidino) pentyl] uanidine, • N, N, N ', N' -tetramethyl-N "-. { 3- [3- (N ', N', N ", N" -tetramethyl-guanidino) propoxy] propi1} guanidine, • N, N, N ', N' -tetramethyl-N "- (2-. {methyl [2- (N ', N', N", N "-tetra-methylguanidino) ethyl] amino. ethyl) guanidine, • N, N, N ', N' -tetramethyl-N "- (2- { 2- [2- (N ', N', N", N "-tetrame-tilguanidino) ethoxy ] ethoxy.} ethyl) guanidine, 2- 2-. { 3- [(1,3-dimethylimidazolidin-2-ylidenamino) methyl] cyclohexylmethylimino} -1, 3-dimethylimidazolidine, 2- 2-. { 2- [2- (1, 3-dimethylimidazolidin-2-ylidenamino) ethylsul-fa il] ethylimino} -!, 3-dimethylimidazolidine, • N- (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidene) -N '- [2- (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidenamino ) ethyl] -N'-methylethane-1,2-diamine, • 2-. { 2- [2- (1, 3-dimethyl-1,3-dihydroimidazol-2-ylidenami-no) ethyldisulfanyl] ethylimino} -1, 3-dimethyl-2,3-dihydro-lH-imidazole, • Nl, N5-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) -2-methylpentane-1,5-diamine and • 2-. { 3- [(1,3-dimethyltetrahydropyrimidin-2-ylidenamino) methyl] benzylimino} -1, 3-dimethylhexahydropyrimidine. The new compounds of general formula (II) are prepared following the synthesis schemes described for the compounds of general formula (I). The invention is also related to the use in cosmetics, especially in hair cosmetics and especially in straightening, of the compounds of formula (II), as well as with a cosmetic process, especially capillary cosmetics and especially for straightening, using at least one compound of formula (II). The compounds of formula (II) can be used for any keratin material, especially for hair and skin, as a care, makeup protection or maintenance product. For example, they can be used in lipsticks, body or hand creams, eyelid shadows, mascaras, eyeliners for eyes or blushes for the cheeks. In the compositions according to the invention intended for a method of straightening, de-straightening or straightening the hair, the multiguanidine which does not belong to the hydroxide family is advantageously present at a molar concentration comprised between 0.1M and 2M, which corresponds to concentrations comprised between 1.4% and 80% by weight with respect to the total weight of the composition, and more advantageously at a concentration comprised between 0.2M and 1M, which corresponds to concentrations comprised between 2.8% and 40% by weight with respect to the total weight of the composition . In cosmetic compositions, especially edging compositions, the molar and weight concentrations of the compounds of general formula (II) are the same as for the compounds of general formula (I). The pH of the compositions according to the invention is preferably between 9.6 and 14 and more particularly between 11 and 13. Advantageously, in the compositions of the invention, the multiguanidine that does not belong to the family of hydroxides constitutes the only active agent of the invention. Uprising. The compositions according to the invention may also contain known reducing agents, such as, for example, thioglycolic acid or thiolactic acid and its ester and amide derivatives, especially glycerol monothioglycolate, cysteamine and its C1-C4 acylated derivatives, such as N-acetylcysteamine or N-propionylcysteamine, cysteine, N-acetylcysteine, thiomalic acid, pantetheine, 2,3-dimercaptosuccinic acid, sulphites or bisulfites of an alkaline or alkaline earth metal, N- (mercaptoalkyl) -? - hydroxyalkylamides described in patent application EP-A-354,835, the N-mono- or N, N-dialkylmercapto-4-butyramides described in the patent application EP-A 368,763, the aminomercaptoalkylamides described in the application EP-A-432,000, the derivatives of the N- (mercaptoalkyl) succinamic acids and of the N- (mercaptoalkyl) succinimides described in the patent application EP-A-465-342, the alkylaminomercaptoalkyl amides described in patent application EP-A-514,282, the azeotropic mixture of 2-hydroxypropyl thioglycolate and (2-hydroxy-1-methyl) ethyl thioglycolate described in patent application FR-A-2,679,448, the mercaptoal-quilaminoamides described in patent application FR-A-2,692,481, the N-mercaptoalkylalkane amides described in the patent application EP-A-653,202, as well as the derivatives of the amidinesulfinic acid described in the application PCT / US01 / 43124, filed by the Applicant. When the compositions according to the invention contain at least one reducing agent, it is advantageously present at a maximum concentration of 20% by weight and preferably comprised between 0.1 and 10% by weight, based on the total weight of the composition. The compositions according to the invention can also contain known hydroxides preferably selected from the hydroxides of alkali metals or alkaline earth metals or transition metals or organic, such as sodium hydroxide, potassium hydroxide, lithium hydroxide, rubidium hydroxide, cesium hydroxide, francium hydroxide, beryllium hydroxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, molybdenum hydroxide, manganese hydroxide, zinc hydroxide, cobalt hydroxide, cadmium hydroxide, cerium hydroxide, lanthanum hydroxide, actinium hydroxide, thorium hydroxide, aluminum hydroxide, guanidinium hydroxide and the hydroxides of quaternary ammoniums. When the compositions of the invention contain at least one hydroxide, it is advantageously present at a concentration of 0.01% to 3.5% by weight and preferably comprised between 0.05 and 1.5% by weight, based on the total weight of the composition. According to a particularly advantageous embodiment of the compositions according to the invention, the latter contain a 0% base belonging to the family of hydroxides, selected in particular from the hydroxides of alkali metals or alkaline earth metals or transition metals or organic. Advantageously, the compositions of the invention contain between 0 and 50% water, preferably between 0 and 30% and more preferably between 0 and 20%. According to a preferred embodiment, the basic compositions also contain a surfactant of the nonionic, anionic, cationic or amphoteric type and among these may be mentioned the alkyl sulfates, the alkylbenzenesulfates, the alkyl ether sulphates, the alkylsulfonates, the quaternary ammonium salts, the alkylbetaines , the oxyethylenated alkylphenols, the fatty acid alkanolamides and the oxyethylenated fatty acid esters, as well as other nonionic surfactants of the hydroxypropyl ether type. When the basic compositions contain at least one surfactant, it is generally present at a maximum concentration of 30% by weight and preferably comprised between 0.5 and 10% by weight with respect to the total weight of the composition. In order to improve the cosmetic properties of the hair, or also to attenuate them or to prevent their degradation, the basic composition may also contain a cationic, anionic, nonionic or amphoteric treatment agent. Particularly preferred treatment agents include those described in French patents No. 2,598,613 and No. 2,470,596. Volatile or non-linear, cyclic or volatile silicones and their mixtures can also be used as treatment agents; polydimethylsiloxanes; quaternized polyorganosiloxanes, such as those described in French Patent Application No. 2,535,730; polyorganosiloxanes with aminoalkyl groups modified by alkoxycarbonylalkyl groups, such as those described in U.S. Pat. No. 4,749,732; polyorganosiloxanes such as the polydimethylsiloxane-polyoxyalkyl copolymer of the dimethicone copolyol type; a polydimethylsiloxane with stearoxi (stearoxydimethicone) end groups; a copolymer of polydimethylsiloxane-dialkylammonium acetate or a copolymer of polydimethylsiloxane-polyalkylbetaine, described in British Patent No. 2,197,352, and organo-modified polysiloxanes by mercapto or mercaptoalkyl groups, such as those described in French Patent No. 1,530. 369 and in European Patent Application No. 295,780, as well as silanes such as stearoxitrimethylsilane. The basic compositions according to the invention can also contain other treatment ingredients, such as cationic polymers, such as those used in the compositions of French patents No. 79,32078 (2,472,382) and 80,26421 (2,495,931), or else cationic polymers of the ionene type, such as those used in the compositions of the Luxembourg patent No. 83703, basic amino acids (such as lysine and arginine) or acids (such as glutamic acid and aspartic acid), peptides and their derivatives, hydrolysates of proteins, waxes, swelling and penetration agents or that allow the efficiency of the reductant to be reinforced, such as the SiO2 / PDMS (polydimethylsiloxane) mixture, dimethylisosorbitol, urea and its derivatives, pyrrolidone, N-alkylpyrrolidones, thiamorpholinone , alkylene glycol or dialkylene glycol alkyl ethers, such as, for example, propylene glycol monomethyl ether, monomethyl ether and dipropylene glycol, ethylene glycol monoethyl ether and diethylene glycol monoethyl ether, and 2-imidazolidinone, as well as other compounds, such as fatty alcohols, lanolin derivatives, active ingredients such as pantothenic acid, anti-hair loss agents, anti-film agents, thickeners, suspending agents, sequestering or complexing agents, opacifying agents and sunscreens, as well as perfumes and preservatives. Advantageously, in the compositions according to the invention, the multiguanidine which does not belong to the family of the hydroxides relaxes keratin fibers without first coming into contact with an organic solvent.

The compositions according to the invention are essentially in the form of a thick cream to keep the hair as tight as possible. These creams are made in the form of "heavy" emulsions, for example, based on glyceryl stearate, glycol stearate, self-emulsifying waxes or fatty alcohols. It is also possible to use liquids or gels containing thickening agents, such as polymers or carboxyvinyl copolymers which "stick" the hair and keep it in the smooth position during the resting time. The compositions according to the invention may also contain at least one adjuvant selected from silicones in soluble, dispersed or microdispersed form; nonionic, anionic, cationic and amphoteric surfactants; ceramides, glycoceramides and pseudoceramides; vitamins and provitamins, including panthenol; vegetable, animal, mineral and synthetic oils; waxes other than ceramides, glycoceramides and pseudoceramides; water-soluble and liposoluble, silicone or non-siliconized sunscreens; pearlizing and opacifying agents; sequestering agents; plasticizing agents; solubilizing agents; acidifying agents; mineral and organic thickeners, antioxidants; hydroxy acids; penetration agents; perfumes, and preservatives. Among the solubilizing agents, there may be mentioned, for example, lower alcohols, such as, for example, ethanol, propanol or isopropanol. The invention also relates to a kit consisting of at least two compartments, containing one of the compartments (i), in a cosmetically acceptable medium, at least one multiguanidine not belonging to the family of hydroxides capable of reacting on the cystines of keratin fibers by a beta-elimination reaction that produces dehydroalanin and that leads to the formation of lanthionine, to relax the keratin fibers in less than 60 minutes. Preferably, the kit according to the invention also contains a supplementary composition (ii) of care, conditioning, make-up, de-makeup, protection, cleaning or washing of the keratin fibers. The compositions of the kits according to the invention are packaged in separate compartments or containers or devices, optionally accompanied by appropriate, identical or different application means, such as brushes, brushes or sponges. Another object of the invention is related to a method of straightening keratin materials using a cosmetic composition containing, in a cosmetically acceptable medium, at least one multiguanidine not belonging to the family of hydroxides, the cosmetically acceptable medium being selected and the multiguanidine in such a way that the multiguanidine not belonging to the family of hydroxides reacts on the cystines of the keratin fibers by a beta-elimination reaction that produces dehydroalanine and that leads to the formation of lanthionine, to relax the keratin fibers in less 60 minutes Advantageously, in the method according to the invention, the duration of the rolling is less than 40 minutes and more advantageously less than 30 minutes. In the hair straightening or de-straightening or straightening procedure according to the invention, the basic composition according to the invention is applied to the hair and then the hair is subjected to a mechanical deformation which allows it to be given a new shape by means of a smoothing operation of the hair. hair with a large tooth comb, with the back of the comb or with the hand. After an exposure time of 5 to 60 minutes, in particular from 5 to 40 minutes, the hair is then re-smoothed and the hair is then thoroughly rinsed. According to the present invention, it is advantageous to subject, after application of the composition according to the invention, the hair to a heat treatment by heating at a temperature of 30 to 60 ° C. In practice, this operation can be conducted by means of a hairdressing helmet, a hair dryer, an infrared ray dispenser and other classic heating devices. A heating iron at a temperature of 60 to 220 ° C and preferably 120 to 200 ° C can be used at the same time as a heating and smoothing means for the hair. Still another object of the invention relates to the use of a multiguanidine not belonging to the family of hydroxides as an active agent for restoring the keratin fibers. The invention also relates to an active agent for restoring the keratin fibers by means of a beta-elimination reaction which produces dehydroalanine and which leads to the formation of lanthionine, which includes at least one multiguanidine not belonging to the family of hydroxides . The invention may be better understood with the aid of the non-limiting examples which follow and which constitute preferential embodiments of the compositions according to the invention. EXAMPLE 1 A simplified edging composition containing N ", N '' '' '-1,3-propanediylbis [N, N, N', N '-tetramethylguanidine] is made (RN: 289474-28-8 ) at a concentration of 0.5M in water as an active de-rhizating agent.This composition is applied to naturally curly African hair for 20 minutes at a temperature of 30 ° C. The hair is effectively straightened, is easy to comb and submit to a hairstyle and are soft to the touch EXAMPLE 2: A simplified edging composition is made containing N ", N" "'- N" "" "- (nitrilotri-2, 1-ethanediyl) tris [N, N, N ', N' -tetramethylguanidine] (RN: 368866-05-1) at a concentration of 0.25 M in water as an active rennetting agent. This composition is applied on naturally curly African hair for 25 minutes at a temperature of 30 ° C. The hair is effectively straightened, is easy to comb and submit to a hairstyle and are soft to the touch. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims

CLAIMS Having described the invention as above, the content of the following claims is claimed as property: 1. Composition, characterized in that it contains, in a cosmetically acceptable medium, at least one multiguanidine not belonging to the family of hydroxides, the cosmetically acceptable medium and the multiguanidine being selected in such a way that the multiguanidine not belonging to the family of hydroxides reacts on the the cystines of the keratin fibers by a beta-elimination reaction that produces dehydroalanine and that leads to the formation of lanthionine, to relax the keratin fibers in less than 60 minutes. Composition according to claim 1, characterized in that the duration of the straightening is less than 40 minutes and more advantageously less than 30 minutes. 3. Composition according to any of the preceding claims, characterized in that the multiguanidine is advantageously not belonging to the family of hydroxides at a molar concentration comprised between 0.1 M and 2 M and more advantageously at a concentration comprised between 0.
2 M and 1 M. 4. Composition according to any of the preceding claims, characterized in that the pH comprises between 9.6 and 14 and more, particularly between 11 and 13. 5. Composition according to any of the preceding claims, characterized in that it contains a 0% base belonging to the family of hydroxides. Composition according to any of the preceding claims, characterized in that it contains 0 to 50% water, preferably 0 to 30% and more preferably still 0 to 20%. 7. Composition according to any of the preceding claims, characterized in that the multiguanidine is selected from the group of compounds that correspond to the following general formula (I): (Or where: • Rl, R'l, R2, R'2, R3, R'3, R4 and RM, identical or different, represent a radical selected from: - a hydrogen atom, - a Cl to C6 alkyl group saturated or unsaturated, linear, such as, for example, methyl or ethyl, or branched, such as, for example, isopropyl or tert-butyl, or also cyclic, such as, for example, cyclopentyl or cyclohexyl, said group being alkyl optionally substituted by the following radical: where R5, R'5, R6 and R '6 have the same meanings as the radicals R1 to RM previously designated; • R1 and R2 and / or R3 and R4 can also together form a divalent radical (CH2) 2 or (CH2) 3 or CH = CH; • A represents a linear or cyclic, saturated or unsaturated C2 to C12 divalent hydrocarbon radical, which may be optionally interrupted by one or more groups such as imino, carboxamido, sulfoxide and sulfone and / or by: - one or more heteroatoms selected from sulfur, oxygen, nitrogen and silicon and optionally substituted by: - a straight or branched Cl to C4 alkyl radical optionally interrupted by one or more heteroatoms such as defined above and optionally substituted by the following radical: R5, R'5, R6 and R '6 have the same meanings as the Rl to RM radicals designated above. 8. Composition according to any of the preceding claims, characterized in that the compounds of formula (I) are selected from: - N, N-bis (1,3-dimethyl-2-imidazolidinylidene) -1, 2-benzenediamine (RN) : 774610-65-0), N- [bis (dimethylamino) methylene] -3- (dimethylamino) -5-imino-2-methyl-2,4,6,6-tetraazaeicosan-20-imidamide (RN: 791543- 84-5), - N, N '-bis (tetrahydro-1,3-dimethyl-2 (1 H) -pyrimidinyl-deno) -1,3-propanediamine (RN: 752232-69-2), 1' , 1", 1 '' '- [1-propanediylbis (nitrilomethane-trail)] tetrakispiperidine (RN: 752232-68-1), - poly (oxy-1,2-ethanediyl) -α- [2- [(1 , 3-dimethyl-2-imidazoli-dinylidene) amino] ethyl] -? - [2- [(1,3-dimethyl-2-imidazo-lidinylidene) amino] ethoxy] (RN: 742679-23-8), N ", N '' '' '-l, 2-ethanediylbis [N, N, N', N '-tetrakis- (1-methylethyl) guanidine (RN: 676488-06-5), N,' -bis (1,3-dihydro-l, 3-dimethyl-2H-imidazol-2-ylidene) -l, 8-naphthalenediamine (RN: 634192-99-7), N, N'-bis (1,3-dimethyl- 2-imidazolidinylidene) -1,8-naphthalenediamine (RN: 501931-38-0), - N ", N" '' '-1,8-biphenylenediylbis [N, N, N', N '-tetramethylguanidine] (RN : 495408-66-7), - N ", N" "'-benzo [c] phenanthrene-1, 12-diylbis [N, N, N', N '-tetramethylguanidine] (RN: 495408-58-7) , - N ", N" '"-4-, 5-phenanthrenodiylbis [N, N, N', N '-tetramethylguanidine] (RN: 495408-50-9), -N", N' '' '' - (9,10-dihydro-4,5-phenanthrenodiyl) bis- [N, N, N ', N' -tetramethylguanidine] (RN: 495408-44-1), - N ", N '' '' '-1 , 2-phenylenebis [N, N, N ', N' -tetramethylguanidine] (RN: 495408-35-0), -? ",? '' '' '-1, 8-naphthalenediylbis- [?,? ,? ' ,? '- tetramethylguanidine] (R ?: 443892-20-4), -? ",? "'' '-9H-flurene-4,5-diylbis- [?,?,?' ,? ' -tetramethylguanidine] (RN: 443892-12-4), -? ' - (tetrahydro-1,3-dimethyl-2- (1H) -pyrimidinylidene) -?,? - bis [2- [(tetrahydro-1,3-dimethyl-2 (1H) -pyrimidini-lideno) amino] ethyl] -1, 2-ethanediamine (RN: 395640-62-7), -? " ,? ' '' '',? ' '' '' '' '- (nitrilotri-2, l-ethanediyl) tris- [?,?,?' ,? ' -tetramethylguanidine] (R ?: 368866-05-1), -? ",? ' '' '' - [2- [[[(bis (dimethylamino) methylene] -amino] -methyl] -2-methyl-1,3-propanediyl] bis [?,?,? ',?' -tetramethylguanidine] ( R ?: 289474-30-2), -? "," "'' '- (2,2-dimethyl-1,3-propanediyl) -bis- [N, N, N', N'-tetramethylguanidine] ( RN: 289474-29-9), - N ", N '' '' '-1,3-propanediylbis [N, N, N', N '-tetramethylguanidine] (RN: 289474-28-8), -? ",? '' '' '-1,2-ethanediylbis [?,?,?',? '-tetramethylguanidine] (RN: 289474-25-5), -?,?' -bis (1, 3 -dihydro-l, 3-dimethyl-2H-imidazol-2-ylidene) -1, 2-ethanediamine (R ?: 216873-26-6), -?,? '' '-1,2-ethanediylbis [?' ,? ',? ",?" -diethylguanidine] (R ?: 211869-99-7), -? ",?' '' '' - [(methyloxy) di-3, 1-propanediyl] bis] - ?,?,? ',?' -tetramethylguanidine] (RN: 196405-86-4), -? ",? '' '' '- [oxobis (2, l-ethanediyloxy-3, 1-propanediyl)] a [?,?,? ',?' -tetramethylguanidine] (R ?: 190442-53-6), -? ",? '" "- [[1,1,3,3-tetramethyl-l, 3-disiloxanediyl ] di-3, 1-propanediyl] bis [?,?,? ',?' -tetramethylguanidine] (R ?: 175989-14-7), -? ",? '' '' '- [[1,3-dimethyl-l, 3-bis (tri-ethyl-silyl) oxy] -1,3-disyloxanediyl] di-3, 1-propanodiyl] is- [?,?,? ' ,? ' -tetramethylguanidine] (R ?: 172283-48-6), -?,? "- 1,6-hexanediylbis [? ' - [bis (dimethylamino) methylene-rea (R ?: 157362-45-3), [bis (dimethylamino) methylene] - [3- [[[[(bis (dimethylamino) methylene] amino] carbonyl] amino] methyl] -3,5, 5-tri-methylcyclohexyl] urea (RN: 157362-44-2), -? ",? ' '' '' - [1,1'-biphenyl] -2, 2 '-diilbis- [?,?,?' ,? ' - tetramethylguanidine] (RN: 144576-63-6), -4,4'-sulphonylbis [N- (1,3-dimethyl-2-imidazolidinyl-deno) benzenamine (RN: 129346-76-5), - ?, ? ' -bis (1,3-dimethyl-2-imidazolidinylidene) -2,8-dibenzothiophenodiamine-5, 5-dioxide (R ?: 128169-35-7), -?,? ' bis (1,3-dimethyl-2-imidazolidinylidene) -4,6-dibenzothiophenodiamine-5, 5-dioxide (R ?: 127330-56-7), -N,? ' -bis (1,3-dimethyl-2-imidazolidinylidene) -1, 2-ethanediamine (RN: 126620-51-7), -? ",? '' '' '-1, 3-phenylenebis [?,?,?' ,? ' -tetramethylguanidine] (R ?: 121648-84-8), -?,? ' -bis [bis (dimethylamino) methylene] butanediamine (R ?: 114491-72-4), -? ",? '"' '-1, 4-phenylenebis [?,?,?' ,? ' -tetramethylguanidine] (R? 113551-45-4), -? ",? '"' '- [[1,3-dimethyl-l- [(pentamethyldi-siloxanyl) -oxy] -3- [( trimethylsilyl) oxy] -1,3-disyloxane-diyl)] di-3,1-propanediyl] is [?,?,? ' ,? ' -tetramethylguanidi-na] (RN: 109956-31-2), -?,? "-bis [(dimethylamino) - (dipentylamino) methylene] -1,4-piperazineadicarboximidamide (R ?: 97983-93-2), - ?,? "- bis [(dimethylamino) - (hexylpropylamino) methylene] -1,4-piperazinadicarboximidamide (R ?: 97983-92-1), -?,?" - bis [(hexylmethylamino) -methylpropyl-amino) methylene ] -1,4-piperazinadicarboximidamide (R ?: 97983-91-0), - N, N "-bis [(butylmethylamino) - (hexylmethylamino) methylene] -1, -piperazineadicarboximidamide (RN: 97983-90-9), -N, N "-bis [(dimethylamino) - (heptymethylamino) methylene] -1, -piperazinadicarboximidamide (RN: 97963-91-2), -N", N '' '' '- [(1,1,3 , 3-tetramethoxy-l, 3-disiloxanediyl) di-3, 1-propanediyl] bis [N, N, N ', N' -tetramethylguanidine] (RN: 69755-28-8), -N ", N '' '' '-1,6-hexanediylbis [N, N, N', N '-tetramethylguanidine] (RN: 64933-93-3), -N ", N' '' '' - (methylenedi-4, 1-phenylene) bis- [N, N, N ', N' -tetramethylguanidine] (RN: 57414-23-0), -N, N "- (ethylphenylene) bis [N '- [bis (dimethylamino) -methylene] urea (RN: 3 9529-23-2) and -2.2'- (sulfonyldiethylene) is [1,1,3,3-tetramethylguani-dine] (RN: 13998-89-5). Composition according to any of claims 7 or 8, characterized in that the compounds of formula (I) are selected from: N- [bis (dimethylamino) methylene] -3- (dimethylamino) -5-imino-2-methyl -2,4, 6, 19-tetraazaeicosan-20-imidamide (RN: 791543-84-5), N, N, '-bis (tetrahydro-l, 3-dimethyl-2 (1H) -pyrimidinyl-deno) - 1,3-propanediamine (RN: 752232-69-2), -poly (oxy-1,2-ethanediyl) -a- [2- [(1,3-dimethyl-2-imidazo-lidinylidene) amino] ethyl] -? - [2- [(1,3-dimethyl-2-imidazolidinylidene) mino] ethoxy] (RN: 742679-23-8), -N ", N '' '' '-1,2-ethanediylbis [N, N, N ', N' -tetrakis (1-methylethyl) guanidine (RN: 676488-06-5), -N, N'-bis (1,3-dihydro-l, 3-dimethyl-2H- imidazol-2-yl-deno) -1,8-naphthalenediamine (RN: 634192-99-7), -N, N'-bis (l, 3-dimethyl-2-imidazolidinylidene) -1,8-naphthalenediamine (RN : 501931-38-0), N ", N '"' '-1, 2-phenylenebis [N, N, N', N '-tetramethylguanidine] (RN: 495408-35-0), - N-hydrochloride , N '' '' '-1, 8-naphthalene-diilbis- [N, N, N', N ' -tetramethylguanidine] (RN: 443892-20-4), N ", N '' '' ', N' '' '' '' '- (nitrilotri-2, l-ethanediyl) tris- [N, N, N ', N' -tetramethylguanidine] (RN: 368866-05-1), -N ", N '' '' '- [2- [[(bis (dimethylamino) methylene] amino] methyl] -2-methyl-1 , 3-propanediyl] bis [N, N, N ', N' -tetramethylguanidine] (RN: 289474-30-2), ", N '' '' '- (2,2-dimethyl-1,3-propanediyl) ) -bis- [N, N, N ', N'-tetramethylguanidine] (RN: 289474-29-9), N ", N' '' '' -1,3-propanediylbis [N, N, N ', N '-tetramethylguanidine] (RN: 289474-28-8), N, N'-bis (1,3-dihydro-l, 3-dimethyl-2H-imidazol-2-ylidene) -1, 2-ethanediamine (RN: 216873-26-6), - N, N '' '-1,2-ethanediylbis [N', N ', N ", N" -diethylguanidine] (RN: 211869-99-7), - N ", N' '' '' [ (methylimino) di-3, 1-propanediyl] -bis- [N, N, N ', N' -tetramethylguanidine] (RN: 196405-86-4), N ", N '' '' '- [oxybis ( 2, l-ethanediyloxy-3, l-propanediyl)] bis [N, N, N ', N' -tetramethylguanidine] (RN: 190442-53-6, - N ", N '' '' '- [[1 , 1,3, 3-tetramethyl-l, 3-disiloxanediyl] di-3, 1-propanediyl] bis [N, N, N ', N' -tetramethylguanidine] (RN: 175989-14-7), - N, N "-1,6-hexanediylbis [N '-bis (dimethylamino) methyleneurea (RN: 157362-45-3), - N", N' '' '' - [1,1'-biphenyl] -2,2 '-diilbis- [N, N, N', N '-tetramethylguanidine] (RN: 144576-63-6), N, N' -bis (1,3-dimethyl-2-imidazolidinylidene) -1, 2-ethanediamine (RN: 126620-51-7), N ", N '' '' '-1, 4-phenylenebis [N, N, N', N'-tetra-methylguanidine] (RN: 113551-45-4), N ", N '' '' '- [(1,1,3,3-tetramethoxy-1,3-disyloxanediyl) -di-3,1-propanediyl] bis [N, N, N', N ' -tetramethylguanidine] (RN: 69755-28-8), N ", N '' '' '-1,6-hexanediylbis [N, N, N', N '- tetramethylguanidine] (RN: 64933-93-3) and 2,2'- (sulfonyldiethylene) bis [1,1,3,3-tetra-methylguanidine] (RN: 13998-89-5). 10. Compounds of general formula (II) useful) characterized by: • Rl, R'l, R2, R'2, R3, R'3, R4 and RM, identical or different, represent a group selected from: - a hydrogen atom and - a methyl, ethyl, propyl radical or isopropyl; R1 and R2 and / or R3 and R4 can also together form a divalent radical (CH2) 2 or (CH2) 3 or CH = CH; • B represents a radical selected from: CR,, 0. , CH, cp s', CHS, CHG * S CH. • when R'l = R'2 = R'3 = RM = CH3 and when R1 / R2 and R3 / R4 respectively form the divalent radical (CH2) 2, B also represents a radical (CH2) 2 or (CH2) ) 5 or (CH2) 6 or a radical: • when R'l = R'2 = R'3 = R'4 = CH3 and when R1 / R2 and R3 / R4 respectively form the divalent radical (CH2) 3, B represents (CH2) 2 or (CH2) 3 or (CH2) 4 or (CH2) 5 or (CH2) 6 or a radical: • when R'l = R'2 = R'3 = RM = CH3 and when R1 / R2 and R3 / R4 form respectively and simultaneously the divalent radical CH = CH, B represents (CH2) 3 or (CH2) 4 or ( CH2) 5 or (CH2) 6 or a radical: • when Rl, R'l, R2, R'2, R3, R'3, R4 and RM represent an ethyl or isopropyl radical, B represents a radical (CH2) 3 or (CH2) 4 or (CH2) 5 or ( CH2) 6 or a radical: • when Rl, R'l, R2, R'2, R3, R'3, R4 and RM represent a methyl radical, B represents a radical (CH2) 4 or (CH2) 5. 11. Compounds of the general formula (II) according to claim 10, characterized in that they are selected from: • N, N, N ', N'-tetraisopropyl-N "- [3- (N', Nr, N", N "-tetraiso-propylguanidino) propyl] guanidine, • N, N, N ', N'-tetraisopropyl-N" - [4- (N', N ', N ", N" -tetraiso-propylguanidino) butyl] guanidine , • N, N, N ', N'-tetraisopropyl-N "- [5- (N', N ',", N "-tetraiso-propylguanidino) pentyl] guanidine, • N, N, N', N ' -tetraisopropyl-N "- [6- (N ', N', N", N "-tetraiso-propylguanidino) hexyl] guanidine, • N, N, N ', N'-tetraisopropyl-N" - (3-. Methyl- [3- (N ', N', N ", N" -tetraisopropylguanidino) propyl] amino Jpropil) guanidine, • N, N, N ', N' -tetraethyl-N "- [3- (N ', N', N ", N" -tetraethylguaneidino] propyl] guanidine, • N, N, N ', N' -tetraethyl-N "- [4- (N ', N', N", N " -tetrathylguane-nidino) butyl] guanidine, • N, N, N ', N' -tetraethyl-N "- [5- (N ', N', N", N "-tetraethylguandino) pentyl] guanidine, • N, N, N ', N' -tetraethyl-N "- [6- (N ', N', N", N "-tetraethylguandine) hexyl] guanidi na, • N, N, N ', N' -tetraethyl-N "- (3-. { methyl- [3- (N ', N', N ", N" -tetraisopropylguanidino) propyl] amino} propyl) guanidine, • N, N'-bis (1,3-dimethylimidazolidin-2-ylidene) butane-1,4-diamine, • N, N'-bis (1,3-dimethylimidazolidin-2-ylidene) pentane-1, 5- diamine, • N, N'-bis (1,3-dimethylimidazolidin-2-ylidene) hexane-1,6-diamine, • N- (1,3-dimethylimidazolidin-2-ylidene) -N '- [3- ( 1,3-dimethyladimidazolidin-2-ylideneamino) propyl] -N'-methylpropane-1,3-diamine, • N, N'-bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) propane-1,3-diamin, • N, N'-bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) butane-1,4-diamine, • N, N'-bis (1, 3-dimethyl-1,3-dihydroimidazol-2-ylidene) pen-tane-1,5-diamine, • N, N '-bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) hexane- 1, 6-diamin, • N- (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) -N '- [3- (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidenamino) propyl] -N'-methylpropane-1,3-diamine, • N, N '-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) ethane-1,2-diamine, • N, N'-bis (1, 3-dimethyltetrahydropyrimidin-2-ylidene) pro-cloth-1,3-diam ina, • N, N'-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) butane-1,4-diamine, • N, N'-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) pentane-1, 5-diamine, • N, N'-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) hexane-1,6-diamine, • N- (1,3-dimethyltetrahydropyrimidin-2-ylidene) -N '- [3 - (1,3-dimethyltetrahydropyrimidin-2-ylidenamino) propyl] -N'-methylpropane-1,3-diamine, • N, N, N ', N' -tetramethyl-N "- [4- (N ', N ', N ", N" -tetramethyl-guanidino) butyl] guanidine, • N, N, N', N '-tetramethyl-N "- [5- (N', N ', N", N "-tetramethyl- guanidino) pentyl] guanidine, • N, N, N ', N' -tetramethyl-N "- [3- (N ', N ', N ", N" -tetramethyl-guanidinomethyl) cyclohexylmethyl] guanidine, • N, N, N', N '-tetraethyl-N "- [3- (N', N ', N", N "- tetraethylamino-nidinomethyl) cyclohexylmethyl] guanidine, • N, N, N ', N' -tetrapropyl-? "- [3- (? ',?',?",? "-tetrapropyl-guanidinomethyl) cyclohexylmethyl] guanidine, • N , N, N ', N' -tetraisopropyl-? "- [3- (? ',?' -?",? "-tetraiso-propylguanidinomethyl) cyclohexylmethyl] guanidine, • N,?,? ' ,? ' -tetraethyl-? "- [3- (? ',?',?",? "-tetraethylgandinidomethyl) encyl] guanidine, •?,?,? ' ,? '- tetrapropyl -? "- [3- (?',? ',?",? "- tetrapropyl-guanidinomethyl) benzyl] guanidine, •?,?,?' ,? ' -tetraisopropyl-? " -3- (? ',?',? ",?" - tetraiso-propylguanidinomethyl) benzyl] guanidine, •? "- [2,2-dimethyl-3- (? ',?',?",? "- tetraethylguanidino) -propyl] -?,?,? ' ,? ' -tetraethylguanidine, •? "- [2,2-dimethyl-3- (? ',?',?",? "-tetrapropylguanidino) -propyl] -?,?,? ' ,? ' -tetrapropylguanidine, •? "~ [2,2-dimethyl-3- (? ',?',?",? "- tetraisopropylguanidi-no) propyl] -?,?,? ' ,? ' -tetraisopropylguanidine, •?,?,? ' ,? ' -tetramethyl-? " -. { 2- [2- (? ',?',? ",?" -tetramethyl-guanidino) ethoxy] ethyl} guanidine, •. ?,?,? ' ,? ' -tetraethyl-? "- { 2- [2- (? ',?',?",? ", -tetraethylguanidino) ethoxy] ethyl.}. guanidine, •?,?,? ' ,? ' -tetrapropyl-? " -. { 2- [2- (? ',?',? ",?" -tetrapro-pilguanidino) ethoxy] ethyl} guanidine, •?,?,? ' ,? ' -tetraisopropyl-? "- { 2- [2- (? ',?',?",? ", -tetraisopropylguanidino) ethoxy] ethyl.} guanidine, • N,?,? ' ,? ' -tetramethyl-? " -. { 2- [2- (? ',?',? ",?" -tetramethyl-guanidino) ethylsulfanyl] ethyl} guanidine, • N, N, N ', N' -tetraethyl-N "-. {2- [2- (N ', N', N", N "-tetraethyl-guanidino) ethylsulfanyl] ethyl} guanidine , • N, N, N ', N'-tetrapropyl-N "-. { 2- [2- (N ', N', N ", N" -tetrapro-pylguanidino) ethylsulfanyl] ethyl} guanidine, • N, N, N ', N' -tetraisopropyl-? "-. {2- [2- (? ',?',?",? "-tetraisopropylguanidino) ethylsulfanyl] ethyl} guanidine, • ?,?,? ' ,? ' -tetramethyl-? " -. { 2- [2- (? ',?',? ",?" -tetramethylguanidino) ethyldisulfanyl] ethyl} guanidine, •?,?,? ' ,? ' -tetraethyl-? "- { 2- [2- (? ',?',", "" -tetraethyl-guanidino) ethyldisulfanyl] ethyl.} guanidine, •?,?,? ' ,? ' -tetrapropyl -? "-. { 2- [2- (? ',?',? ",?" - tetrapro-pilguanidino) ethyldisulfanyl] ethyl} guanidine, •?,?,? ' ,? ' -tetraisopropyl-? "- { 2- [2- (? ',?',?",? "," -tetraisopropylguanidino) ethyldisulfanyl] ethyl.}. guanidine, •?,?,? ' ,? ' -tetramethyl-? "- [2-methyl-5- (? ',?',?",? "~ tetra-methylguanidino) pentyl] guanidine, •?, N,? ' ,? ' -tetraethyl-? "- [2-methyl-5- (? ',?',?",? "-tetra-ethylguanidino) pentyl] guanidine, •?,?,? ' ,? ' -tetrapropyl -? "-. { 2-methyl-5- (? ',?',? ",?" - tetra-propylguanidino) pentyl] guanidine, •?,?,? ' ,? ' -tetraisopr.opil -? "- [2-methyl-5- (? ',?',?",? "- te-traisopropylguanidino) pentyl.} guanidine, •?,?,? ' ,? ' -tetrametil -? "-. { 3- [3- (? ',?',? ",?" -tetramethyl-guanidino) propoxy] propyl} guanidine, • N, N, N ', N' -tetraethyl-N "-. {3- [3- (N ', N', N", N "-tetraethyl-guanidino) propoxy] propyl} guanidine , • N, N, N ', N' -tetrapropyl-N "-. { 3- [3- (N ', N', N ", N" -tetrapro-pylguanidino) propoxy] propyl} guanidine, • N, N, N ', N'-tetraisopropyl-N "-. {3- [3- (N', N ', N", N "-tetraisopropylguanidino) propoxy] propyl} guanidine, • N, N, N ', N' -tetramethyl-N "- (2- { Methyl [2- (N ', N', N", N "-tetra-methylguanidino) ethyl] amino.} Ethyl) guanidine, • N, N, N ', N' -tetraethyl-N "- (2-. {methyl [2- (N ', N',", N "-tetra-ethylguanidino) ethyl] amino.}. ethyl) guanidine, • N, N, N ', N' -tetrapropyl-N "- (2- { methyl [2- (N ', N', N", N "-te-trapropi-guanidino) ethyl] amino Ethyl) guanidine, • N, N, N ', N' -tetraisopropyl-N "- (2-. {methyl [2- (N ', N', N", N "-tetraisopropylguanidino) ethyl] amino.}. ethyl) guanidine, • N, N, N ', N' -tetramethyl-N "- (2- { 2- [2- (N ', N', N", N "-tetra- methylguanidino) ethoxy] ethoxy.} ethyl) guanidine, • N, N, N ', N' -tetraethyl-N "- (2-. {2- 2- [N ', N', N", N "-tetra-ethylguanidino) ethoxy] ethoxy.} ethyl) guanidine, • N, N, N ', N' -tetrapropyl-N" - (2-. {2- 2- [N ', N', N ", N" -tetra-propylguanidino) ethoxy] ethoxy.} Ethyl) guanidine, • N, N, N ', N' -tetraisopropyl-N "- (2-. { 2- [2- (N ', N', N ", N" -te-traisopropylguanidino) ethoxy] toxi} ethyl) guanidine, • 2- . { 3- [(1,3-dimethylimidazolidin-2-ylidenamino) methyl] cyclohexylmethylimino} - !, 3-dimethylimidazolidine, • 2-. { 3- [(1,3-dimethylimidazolidin-2-ylidenamino) methyl] benzylamino} -1, 3-dimethylimidazolidine, • N, N'-bis (1,3-dimethylimidazolidin-2-ylidene) -2, 2-dimethyl-1-propane-1,3-diamine, 2-. { 2- [2- (1, 3-dimethylimidazolidin-2-ylidenamino) ethylsul-fanyl] ethylimino} -1, 3-dimethylimidazolidine, 2- 2-. { 2- [2- (1, 3-dimethylimidazolidin-2-ylidenamino) ethyldisulfanyl] ethylimino} -1, 3-dimethylimidazolidine, • Nl, N5-bis (1,3-dimethylimidazolidin-2-ylidene) -2-methyl-pentane-1,5-diamine, • N- (1,3-dimethylimidazolidin-2-ylidene) ) -N '- [2- (1, 3-dimethyladimidazolidin-2-ylidenamino) ethyl] -N'-methylethane-1,2-diamine, • Nl, N5-bis (1,3-dimethyl-1, 3-dihydroimidazol-2-ylidene) -2-methylpentane-1,5-diamine, • N- (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) -N '- [2- (1, 3 -dimethyl-1,3-dihydroimidazol-2-ylideneamino) ethyl] -N'-methylethane-1,2-diamine, • 2-. { 3- [(1,3-dimethyl-l, 3-dihydroimidazol-2-ylidenamino) -methyl] cyclohexylmethylimino} -1, 3-dimethyl-2, 3-dihydro-1H-imidazole, • N, N'-bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) -2,2-dimethylpropane-1, 3-diamine, • 2-. { 3- [(1,3-dimethyl-1,3-dihydroimidazol-2-ylidenamino) -methyl] -benzylimino} -1, 3-dimethyl-2,3-dihydro-1H-imidazole, • 2- . { 2- [2- (1, 3-dimethyl-1,3-dihydroimidazol-2-ylidenami-no) ethyldisulfanyl] ethylimino} -1, 3-dimethyl-2,3-dihydro-lH-imidazole, • 2-. { 2- [2- (1, 3-dimethyl-1,3-dihydroimidazol-2-ylidenamino) ethylsulfanyl] ethylimino} -1,3-dimethyl-2,3-dihydro-lH-i idazole, • Nl, N5-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) -2-methylpentane-1,5-diamine, •? - ( 1,3-dimethyltetrahydropyrimidin-2-ylidene) -? - [2- (1,3-dimethyltetrahydropyrimidin-2-ylidenamino) ethyl] -? ' -methalene-1, 2-diamine, • 2-. { 3- [(1,3-Di-ethyltetrahydropyrimidin-2-ylidenamino) ethyl] cyclohexylmethylimino} -1, 3-dimethylhecahydropyrimidine, •?,? ' bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) -2,2-dimethylpropane-1,3-diamine, 2-. { 3- [(1,3-dimethyltetrahydropyrimidin-2-ylidenamino) methyl] benzylimino} -1, 3 -dimethylhexahydropyrimidine, 2- 2-. { 2- [2- (1,3-dimethyltetrahydropyrimidin-2-ylidenamino) -ethyldisulfanyl] ethylimino} -1,3-dimethylhexahydropyrimidine and • 2- . { 2- [2- (1, 3-dimethyltetrahydropyrimidin-2-ylidenamino) -ethylsulfanyl] ethylimino} -1, 3-dimethylhexahydropyrimidine. 12. Compounds of the general formula (II) according to any of claims 10 or 11, characterized in that they are selected from: • N, N, N ', N' -tetraisopropyl -? "- [3- (? ',? ',? ",?" -tetraisopropylguanidino) propyl] guanidine, •?,?,?' ,? ' -tetraisopropyl -? "- [4- (? ',?',?",? "-tetraiso-propylguanidino) util] guanidine, •?,?,? ' ,? ' -tetraethyl-? "- [3- (? ',?',?",? "-tetraetilgua-nidino) propyl] guanidine, •?,?,? ' ,? ' -tetraethyl-? "- [4- (? ',?',?",? "- tetraetilgua-nidino) butyl] guanidine, •?,? ' -bis (1,3-dimethylimidazolidin-2-ylidene) utane-1,4-diamine, •? - (1,3-dimethyl-imidazolidin-2-ylidene) -? - [3- (1,3-dime-tilimidazolidin-2-ylidenamino) propyl] -? ' -methylpropane-1,3-diamine, •?,? -bis (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidene) propane-1,3-diamine, •?,? -bis (1,3-dimethyl-1,3-dihydroimidazol-2-ylidene) utane-1,4-diamine, •? - (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidene) -? - [3- (1, 3-dimethyl-l, 3-dihydroimidazol-2-ylideneamino) propyl] -? ' methylpropane-1,3-diamine, •?,? -bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) ethane-1,2-diamine, •?,? bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) propane-1,3-diamine, • N, N, N ', N' -tetramethyl-N "- [4- (N ', N', N", N "-tetramethylguanidino) butyl] guanidine, • N, N, N ', N'-tetramethyl-N" - [3- (N', N ', N ", N" -tetramethyl-nidinomethyl) cyclohexylmethyl] guanidine , • N, N, N ', N' -tetraethyl-N "- [3- (N ', N', N", N "-tetraethylgua-nidino ethyl) benzyl] guanidine, • N" - [2,2 -dimethyl-3- (N ', N', N ", N" -tetraethylguanidino) propyl] -N, N, N ', N' -tetraethylguanidine, • N, N, N ', N' -tetramethyl-N " -. {2- [2- (N ', N', N ", N" -tetramethyl-guanidino) ethoxy] ethyl} guanidine, • N, N, N ', N' -tetramethyl-N "- . { 2- [2- (N ', N', N ", N" -tetramethylguanidino) ethylsulfanyl] ethyl} guanidine, • N, N, N ', N' -tetramethyl-N "-. {2- [2- (N ', N', N", N "-tetramethyl-guanidino) ethyldisulfanyl] ethyl} guanidine , • N, N, N ', N' -tetramethyl-N "- [2-methyl-5- (N ', N', N", N "-tetramethylguanidino) pentyl] guanidine, • N, N, N ' , N '-tetramethyl-N "- { 3- [3- (N', N ', N", N "-tetramethyl-guanidino) propoxy] propyl.} Guanidine, • N, N, N', N '-tetramethyl-N "- (2-. {Methyl [2- (N', N ', N", N "-tetramethylguanidino) ethyl] amino.} Ethyl) guanidine, • N, N, N' , N '-tetramethyl-N "- (2- { 2- [2- (N', N ', N", N "-tetrame-tilguanidino) ethoxy] ethoxy.} Ethyl) guanidine, • 2- {.3- [(1,3-dimethylimidazolidin-2-ylidenamino) methyl] cyclohexylmethylimino} -1, 3-dimethylimidazolidine, • 2- { 2- [2- (1,3-dimethylimidazolidin- 2-ylidenamino) ethylsulpholyl] ethylimino} -1, 3-dimethylimidazolidine, • N- (1,3-dimethyl-l, 3-dihydroimidazol-2-ylidene) -N '- [2- (1, 3 -dimethyl-l, 3-dihydroimidazol-2-ylidenamino) ethyl] -N'-methylethane-1,2-diamine, • 2- { 2- [2- (1,3-dimethyl-1,3-dihydroimidazol-2-ylidenami-no) ethyldisulfanyl] ethylimino} -1, 3-dimethyl-2,3-dihydro-1H-imidazole, • Nl, N5-bis (1,3-dimethyltetrahydropyrimidin-2-ylidene) -2-methylpentane-1,5-diamine and • 2-. { 3- [(1,3-dimethyltetrahydropyrimidin-2-ylidenamino) methyl] benzylimino} -1, 3-dimethylhexahydropyrimidine. 13. Composition according to any of the preceding claims, characterized in that it also contains at least one adjuvant selected from silicones in soluble, dispersed or microdispersed form; nonionic, anionic, cationic and amphoteric surfactants; ceramides, glycoceramides and pseudoceramides; vitamins and provitamins, including panthenol; vegetable, animal, mineral and synthetic oils; waxes other than ceramides, glycoceramides and pseudoceramides; water-soluble and liposoluble, silicone or non-siliconized sunscreens; pearlizing and opacifying agents; sequestering agents; plasticizing agents; solubilizing agents; acidifying agents; mineral and organic thickeners, antioxidizing agents; hydroxy acids; penetration agents; perfumes, and preservatives. 14. Kit, characterized in that it has at least two compartments, containing one of the compartments (i), in a cosmetically acceptable medium, at least one multiguanidine not belonging to the family of hydroxides capable of reacting on the cystines of the keratin fibers by beta-elimination reaction that produces dehydroalanin and that leads to the formation of lanthionine, to relax the keratin fibers in less than 60 minutes. 15. Kit according to any of the preceding claims, characterized in that it also contains a supplementary composition (ii) care, conditioning, make-up, make-up removal, protection, cleaning or washing of keratin fibers. 16. Process for straightening keratin materials, characterized in that it uses a cosmetic composition containing, in a cosmetically acceptable medium, at least one multiguanidine not belonging to the family of hydroxides, the cosmetically acceptable medium and the multiguanidine being selected in such a way that the multiguanidine not belonging to the hydroxide family reacts on the cystines of the keratin fibers by a beta-elimination reaction that produces dehydroalanine and that leads to the formation of lanthionine, to relax the keratin fibers in less than 60 minutes. Method for restoring the keratin materials according to claim 16, characterized in that the hair is subjected to a thermal treatment by heating at a temperature between 30 and 60 ° C after application of the composition. 18. Method for restoring the keratin materials according to claim 16 or 17, characterized in that it uses, at the same time as heating and smoothing means, a heating iron at a temperature of 60 to 220 ° C and preferably of 120 at 200 ° C. 19. Method for straightening keratin materials according to claim 16 to 18, characterized in that the duration of the straightening is less than 40 minutes and more advantageously less than 30 minutes. 20. Use of a multiguanidine not belonging to the family of hydroxides as an active agent for restoring keratin fibers. 21. Active agent for straightening the keratin fibers by means of a beta-elimination reaction that produces dehydroalanine and which leads to the formation of lanthionine, characterized in that it includes at least one multiguanidine not belonging to the hydroxide family. 22. Cosmetic use of the compounds of formula (II).