DETERGENT COSMETIC COMPOSITIONS COMPRISING FOUR SURFACTANTS, A CATIONIC POLYMER AND A BENEFICIAL AGENT, AND USE THEREOF The present invention relates to novel detergent cosmetic compositions for keratin materials, m particular for human keratin materials such as the hair, comprising, in a cosmetically acceptable aqueous support, at least one sulfate, sulfonate or phosphate anionic surfactant, at least one carboxylic anionic surfactant other than the preceding surfactant, at least one amphoteric surfactant and at least one nomonic surfactant of alkylpolyglycoside type. The invention also relates to the use of said compositions in the abovementioned cosmetic application. It is well known that hair is sensitized or embrittled to varying degrees by the action of atmospheric agents and especially light, water and humidity, and also by repeated mechanical or chemical treatments such as brushing, combing, washing, bleaching, permanent-waving, relaxing and/or dyeing. Numerous publications disclose that natural light destroys certain amino acids of the hair. These attacking factors impair the hair fibers and reduce their mechanical properties, for instance their tensile strength, breaking load and elasticity, or their resistance to swelling in an aqueous medium. The hair is dull, coarse and brittle. It is difficult to disentangle and to style. It is also known that light and washing agents have a tendency to attack the natural color of the hair and also the artificial color of dyed hair. The hair color gradually fades or turns toward unesthetic or undesirable shades. Substances for protecting the hair against the degradation caused by atmospheric attacking factors, such as light and heat, and treatments, have been sought for many years in the cosxuetics industry. In particular, products that improve the cosmetic properties (especially the disentangling, softness, smoothness,, sheen, etc.) and products that protect the color of naturally colored or artificially dyed keratin fibers and that preserve or reinforce the intrinsic mechanical properties of keratin fibers (their tensile strength, breaking load and elasticity, or their resistance to swelling in an aqueous medium), are sought. Moreover, the skin may also be impaired to varying degrees by the action of atmospheric agents and also by the repeated action of detergent products. The skin tissue may be burnt, and the skin becomes dry and coarse and loses its natural elasticity. The appearance of dandruff, of excess seborrhea or, conversely, of excess dryness may then be observed. It is known practice to protect the hair and the skin from the effects of light by applying thereto water-soluble or water-insoluble, polymeric or nonpolymeric UV-screening agents, nanoparticles, antioxidants, metal-complexing or chelating agents, or free-radical scavengers - For better disentangling and prevention of coarseness of the hair, water soluble or water-insoluble monomeric or polymeric conditioning agents may also be applied thereto. The compositions of the prior art allow the problems mentioned to be solved to a certain extent, but their use is unsatisfactory. The reason for this is that repeated applications of these compositions often have the effect of giving the hair an unpleasant feel, loss of volume and liveliness of the head of hair, and occasionally loss of sheen. Moreover, such compositions produce a persistent greasy feel on the skin. In the field of "rinse-out" cosmetic compositions, such as shampoos,, shower gels, facial makeup removers or shaving foams, detergent compositions comprising agents that are beneficial to the hair or the skin are known. These beneficial ingredients are generally introduced into the composition to facilitate the disentangling of the hair, to improve the feel qualities of the keratin fiber or of the skin, or else to promote the moisturization of the latter. In this context., cationic polymers, silicones and emollients such as polyols are the ingredients most commonly used. To obtain the intended beneficial effect, it is necessary to introduce into the rinse-out composition an amount of beneficial agent much greater than that required to obtain the effect. For rinse-out detergent compositions, the majority of the beneficial agent is in fact removed during the rinsing of the composition, and the effective part of the acenr contained in the composition is consequently very small. However, at the current time, no rinse-out detergent compositions exist that can substantially increase the amount of beneficial agent vectorized after rinsing. Such compositions would make it possible to use much less beneficial agent to provide the same level of beneficial effect. The Applicant has discovered, surprisingly, that oy using, in a cosmetically acceptable medium, at least cne combination of four surfactants and of a particular cationic polymer in combination with at least one agent that is beneficial to keratin materials, the drawbacks mentioned above can be overcome. In particular, it is possible to increase the deposition of the beneficial agent on the keratin materials and thereby to increase the efficacy of said beneficial agents or to reduce the amount of said agent used. One subject of the invention is thus a detergent cosmetic composition, wherein it comprises, in a cosmetically acceptable aqueous medium, (A) at least one. anionic surfactant comprising at . least one group chosen from sulfate, sulfonate and phosphate, (B) at least one carboxylic anionic: surfactant other than the surfactant mentioned in (A), (C) at least one amphoteric or zwitterionic surfactant, (D) at least one elkylpolyglycoside nonionic surfactant, (E) at least one cationic polymer with a cationic charge density of greater than 4 meg./g and (F) at least one agent that is beneficial to keratin materials other -han (E), the sulfate or sulfonate anionic surfactant/amphoteric surfactant weight ratio ranging from 0.1 to 2. Without wishing to limit the present invention to any theory, it would appear that, during rinsing, there are particular interactions and/or affinities between the agent that is beneficial to keratin materials, the combination of surfactants in accordance with the invention, the cationic polymer and the hair, which promote uniform, substantial and long-lasting deposition of s£id agents that are beneficial to keratin materials and of the cationic polymer on the surface of said hair, this qualitative and quantitative deposition probably being one of the causes of the improvement observed as regards the final properties, in particular the ease of styling, the disentangling, the smoothness, the softness and the sheen of the treated hair when a conditioning agent is used. All these discoveries form the basis of the present invention. Another subject of the invention concerns the use of at least one combination comprising (A) at least one anionic surfactant comprising at least one group chosen from sulfate, sulfonate and phosphate, (B) at least one carboxylic anionic surfactant other than the surfactan-mentioned in (A), (C) at least one amphoteric or zwittericnic surfactant, (D) at least , one alkylpolyglycoside nonionic surfactant, (E) at least one cationic polymer with a cationic charge density of greater than 4 meq./g, the sulfate or sulfonate anionic surfactant/amphoteric surfactant weight ratio ranging from 0.1 to 2, in, or for the manufacture of, a cosmetic composition comprising an agent that is beneficial to keratin materials. A subject of the invention is also the use of at least one combination comprising (A) at least one anionic surfactant comprising at least one group chosen from sulfate, sulfonate and phosphate, (B) at least one carboxylic anionic surfactant other than the surfactant mentioned in (A), (C) at least one amphoteric or zwitterionic surfactant, (D) at least one alkylpolyglycoside nonionic surfactant, (E) at least one cationic polymer with a cationic charge density of greater than 4 meq./g, the sulfate or sulfonate anionic surfactant/amphoteric surfactant weight ratio ranging from 0.1 to 2, in a composition comprising an agent that is beneficial to keratin materials, for increasing the efficacy of this agent that is beneficial to keratin materials. A subject of the present invention is also the use of at least one combination comprising (A) a: least one anionic surfactant comprising at least one group chosen from sulfate, sulfonate and phosphate, (B) at least one carboxylic anionic surfactant other than the surfactant mentioned in (A), (C) at least one amphoteric or zwitterionic surfactant, (D) at least one alkylpolyglycoside nonionic surfactant, (E) at least one cationic polymer with a cationic charge density of greater than 4 meq./g, the sulfate or sulfonate anionic surfactant/amphoteric surfactant weight ratio ranging from 0.1 to 2, in a composition comprising an agent that is beneficial to keratin materials, for improving the deposition and/or fixing of said beneficial agent on the keratin materials. A subject of the invention is also the cosmetic use of the above compositions for cleansing and/or removing makeup from and/or conditioning keratin materials such as the hair and the skin. The various subjects of the invention will now be described in detail. All the meanings and definitions of the compounds used in the present invention given below are valid for all cf the subjects of the invention. According to the invention, the term "at least one" means "one", "two", "three"... or more. An agent that is beneficial to keratin materials is an agent that is especially capable of protecting, enhancing, conditioning, treating and/or facilitating the shaping of keratin materials, and in particular the hair. (A) Sulfate or sulfonate surfactants According to the invention, the sulfate or sulfonate anionic surfactants are anionic surfactants comprising at least one sulfate (-OS03H or -OS03-) function and/or one sulfonate (-SO3H or -SO3-) function. The sulfate or sulfonate anionic surfactants that may be used, alone or as mixtures, in the context of the present invention are salts (in particular alkali me~al salts, especially of sodium, ammonium salzs, amine salts, amino alcohol salts or magnesium salts) of alkyl sulfates, alkylamido sulfates, alkyl ether sulfates, alkylamido ether sulfates, alkylaryl ether sulfates, alkyl ether sulfosuccinates, acyl isethionates or methyl acyl taurates; the alkyl or acyl radical of all these various compounds preferably containing from 8 to 24 carbon atcras, and the aryl radical preferably denoting a phenyl or benzyl group. The average number of ethylene oxide or propylene oxide groups may especially range from 2 to 50 and more particularly from 2 to 10. Among these anionic surfactants, it is preferred to use C8-C14 and more particularly C12-C14 alkyl ether sulfate salts. These salts preferably comprise from 2 to 5 ethylene oxide groups. Among said anionic surfactants, sodium, trie~hanolamine, magnesium or ammonium (C12-C14) alkyl sulfates, sodium, ammonium or magnesium (C12-C14)alkyl ether sulfates oxyethylenated with 2.2 mol of ethylene oxide, sodium cocoylisethionate and methyltaurates are preferably used. Sodium cocoyl isethionate and methyl acyltaurates may also be used as sulfate or sulfonate surfactant. The sulfate or sulfonate anionic surfactants are generally present in a proportion of from 1% to 50% by-weight, preferably from 2% to 25% by weight, particularly from 2% to 25% by weight, more particularly from 3% to 20% by weight, better still from 3% to 10% by weight and even better still from 3.5% to 8% by weight relative to' the total weight of the composition. (B) Carboxylic anionic surfactants According to the invention, the carboxylic anionic surfactants are anionic surfactants comprising at leas; one carboxylic function (-COOH) optionally in salt form (-C00-) . The anionic surfactants of carboxylic type other than the surfactants (A) preferably comprise no sulfate or sulfonate functions and may be chosen especially from alkyl D-galactoside uronic acids and salts thereof, polyoxyalkyler.ated. (C6-C24) alkyl ether carboxylic acids, polyoxyalkyleneted {C6-C24)alkylaryl ether carboxylic acids and salts thereof, polyoxyalkylenated (C6-C24)alkylaraido ether carboxylic acids and salts thereof, in particular those containing from 2 to 50 alkylene oxide groups, in particular ethylene oxide, such as the compounds sold by the company Kao under the name Akypo, (C6-C24)3cyl sarcosinates and salts thereof, (C6-C24) acyl lactylates and salts thereof and (C6-C24)acyl glutamates. (C6-C24) Alkylpolyglycoside carboxylic esters such as alkylglucoside acetates, alkylglucoside citrates and alkylpolyglycoside tartrates may also be used. Such products are sold especially under the names Eucarol APG/EC and Eucarol APG/3T by the company Lamberti, and Plantapon LGC Sorb by the company Cognis, Mixtures of these surfactants nay also be used. The salts are chosen in particular from alkali metal salts, especially of sodiu:n, ammonium salts, amine salts, salts of amino alcohols such as triethanolamine or monoethanolamine, and magnesium salts. Polyoxyalkylenated (C6-C24) alkyl ether carboxylic acids and salts thereof, polyoxyalkylenated (C6-C24)alkylamido ether carboxylic acids and salts thereof, and in particular those containing from 2 to 15 alkylene oxide groups, (C6-C24)alkylpolyglyccsidecarboxylic esters and salts thereof, and (C6-C24}acyl glutamates and salts thereof, and mixtures thereof, are preferably used. Polycxyaikylenated (C6-C24)alkyl ether carboxylic acics and salts thereof, and polyoxyalkylenated (C6-C24)alkylamido ether carboxylic acids, in particular those containing from 2 to 15 alkylene oxide groups, and salts thereof, and mixtures thereof, are more particularly used. The anionic surfactants of the polyoxyalkylenated carboxylic ether acid or salt type are, in particular, those that'correspond to formula (1) below: Ri-(OC2H4)n-CCH2COOA (1) in which: R1 represents a linear or branched C8-C22 alkyl or alkenyl radical or mixture of radicals, a (C8-C9)alkylpher.yl radical, a radical R2CONH-CH2-CH2-with R2 denoting a linear or branched C11-C21 alkyl or alkenyl radical, and n is an integer or decimal number (average value) that may range from 2 to 24 and preferably from 2 to 10, the alkyl radical containing between 6 and 20 carbon atoms approximately and preferably from 8 to 18 carbon atoms, and aryl preferably denoting phenyl. A denotes H, ammonium, Na, K, Li, Mg or a monoethanol-amine or triethanolamine residue. Mixtures of compounds of formula (1) may also be used, in particular mixtures in which the groups R1 are different. The oxyalkylenated ether carboxylic acids or salts thereof preferably used according to the invention are chosen from those of formula (z) in which R1 denotes a (C12-C14) alkyl, cocoyl or oleyl radical or mixture of radicals; a nonylphenyl or octylphenyl radical, A denotes a hydrogen or sodium atom, and n ranges from 2 to 2 0 and preferably from 2 to 10. Even more preferentially, compounds of formula (I) are used in which R denotes a (C12) alkyl radical, A denotes a hydrogen or sodium atom and n ranges from 2 to 1C. Among the commercial products that may preferably be used are the products sold by the company Chem Y under the names: Akypo® NP 70 (R = nonylphenyl, n = 7, p = 0, A = H) ; Akypo® NP 40 (R = nonylphenyl, n = 4, p = 0, A = H) ; Akypo® OP 40 (R = octylphenyl, n = 4, p = 0, A = H) ; Akypo® OP 80 (R = octylphenyl, n = 8, p = 0, A = H); Akypo® CP 190 (R = octylphenyl, n = 19, p = 0, A = H); Akypo® RLM 38 (R = (C1a-C14) alkyl, n=3.8, p=0, A= H) ; Akypo® RLM 38 NV (R = (C12-C14) alkyl, n = 4, p = 0, A = Na> ; Akypo® RLM 45 {R - (C12-C14) alkyl, n = 4.5, p = C, A = H); Akypo® RLM 45 NV (R - {C12-C14) alkyl, n = 4.5, p = 0, A = Na) ; Akypo® RLM 100 (R = (C12-C14) alkyl, n = 1C, p = 0, A = H; ; Akypo® RLM 100 NV (R = (C12-C14) alkyl, n - 10, p - 0, A = Na) ; Akypo® RLM 130 (R - (C12-C14) alkyl, n = 13, p - 0, A = H); Akypo® RLM 160 NV (R = (C12-C14) alkyl, n = 16, p = 0, A = Na); or by the company Sancioz under the names: Sandopan DTC-Acid (R = (C13) alkyl, n = 6, p = 0, A = H) ; Sandopan DTC (R = (C13) alkyl, n = 6, p = C, A = Na); Sandopan LS 24 (R = (C12-Ci4) alkyl, n = 12, p = 0, A = Na) ; Sandopan JA 36 (R = (C13) alkyl, n = 18, p = 0, A = H), and more particularly the products sold under the following names: Akypo® RLM 45; Akypo® RLM 100; Akypo® RLM 38. The carboxylic anionic surfactants other than the surfactants mentioned in A) are generally present in a proportion of from 0.5% to 15% by weight, preferably from 1% to 10% by weight, more particularly from 1.5% to 8% by weight and even more preferentially from 21 to 5% by weight relative to the total weight of the composition. (C) Amphoteric and/or zwitterionic surfactant(s): The amphoteric and/or zwitterionic surfactants, whose nature is not a critical feature in the context of the present invention, can be, in particular (nonlimiting list), aliphatic secondary or tertiary amine derivatives in which the aliphatic radical is a linear or branched chain containing 8 to 22 carbon atoms and containing at least one water-soluble anionic group (for example carboxylate, sulfonate, sulfate, phosphate or phosphonate) ; mention may also be made of (C8-C2a)-alkylbetaines, sulfcbetaines, (C8-C20) alkylamido (C1-C6) -alkylbetain.es or (C8-C20) alkylamido (C1-C5) alkylsulfo-betaines. Among the amine derivatives, mention may be made of the products as described in patents US 2 52 3 37 8 and US 2 781 354 and having the structures: (Formula Removed) in which: R2 CO denotes a C6-C24 acyl radical, for example a radical present in hydrolyzed coconut oil, an octoyl, decoyl or dodecanoyl radical, and mixtures thereof, R3 denotes a (3-hydroxyethyl grcup and R4 a carboxymethyl group; and (Formula Removed) in which: B represents -CH2CH2OX', C represents -(CH2)z-Y', with z = 1 or 2, X' denotes the -CH2CH2-COOH group or a hydrogen atom, Y' denotes -COOH or the -CH2-CHOH-EO2H radical, R'2CO denotes a C6-C24 acyl radical, for example a radical present in hydrolyzed coconut, oil or linseed oil, or an octoyl, decoyl or dodecanoyl, stearoyl, isostearoyl or oleoyl radical, and mixtures thereof. These compounds are classified in the CTFA dictionary, 5th edition, 1993, under the names disodium coco-amphodiacetate, discdium lauroamphodiacetate, disodium capryiamphodiacetate, disodium capryloamphodiacetate, disodium cocoamphodipropionate, disodium lauro~ arnphodipropionate, disodium caprylamphodipropionate, disodium caprylcamphodipropionate, lauroampho-cipropionic acid, cccoamphodipropionic acid, An example that may be mentioned is disodium cocoampho-diacetate, sold under the trade name Miranol® C2M Concentrate by the company Rhodia Chimie. According to the present invention, it is more particularly preferred to use amphoteric surfactants belonging to the betaine group such as alkylbetaines, in particular the cocoylbetaine sold under the name Dehyton AB 30 as an aqueous solution containing 30% AM by the company Henkel, or alkylamidobetaines, in particular cocaix.idopropylbetair.e, such as Tegobetaine® F5 0 sold by the company Goldschmidt. The amphoteric surfactant(s) is (are) generally present in amounts ranging from 0.1% to 20% by weight, preferably from 1% to 15% by weight, more particularly from 2% to 10% by weight and better still from 3% to 7% by weight relative to the total weight of the composition. (D] Alkylpolyglycoside nonionic surfactant[5) : The alkylpolyglycoside nonionic surfactants may be more particularly represented by the following general formula: (Formula Removed) in which R1 represents a linear or branched alkyl and/or alkenyl radical containing from about 8 to 24 carbon atoms, an alkylphenyl radical in which the linear or branched alkyl radical contains from 8 to 24 carbon atoms, R2 represents an alkylene radical containing from about 2 to 4 carbon atoms, G represents a sugar unit containing 5 or 6 carbon atoms, t denotes a value ranging from 0 to 10 and preferably from 0 to 4, and v denotes a value ranging from 1 to 15. Alkylpolyglycosides that are preferred according to the present invention are compounds of formula (4) in which R1 more particularly denotes a saturated or unsaturated, linear or branched alkyl radical containing from 8 to 18 carbon atoms, t denotes a value ranging from 0 to 3 and even more particularly equal to 0, and G may denote glucose, fructose or galactose, preferably glucose. The degree of polymerization, i.e. the value of v in formula (4), may range from 1 to 15 and preferably from 1 zo 4. The mean degree cf polymerization is more particularly between 1 and 2 and even. more preferentially from 1.1 to 1.5. The glycoside bonds between the sugar units are of 1-6 or 1-4 type and preferably of 1-4 type. Compounds of formula (4) are especially represented by the products sold by the company Cognis under the names Plantaren® (600 CS/U, 1200 and 2000) or Plantacare® (818, 1200 and 2000) . It is also possible to use the products sold by the company SEPPIC under the names Triton CG L10 (or Oramix CG 110) and Triton CG 312 (or Orartiix® NS 10) , the products sold by the company BASF under the name Lutensol GD 70 or the products sold by the company Chem Y under the name AGIO LK. It is also possible to use, for example, C8/C16 alkyl poiyglucoside-1,4 as an aqueous 53% solution sold by Cognis under the reference Plantacare® 818 UP. The nonionic surfactant(s) of alkylpolyglycoside type is (are) generally present in amounts ranging from 0.1% to 20% by weight, preferably from 1% to 15% by weight, more particularly from 2% to 10% by weight and better still from 3% to 8% by weight relative to the total weight of the composition. The minimum amount of surfactants is the amount that is sufficient to give the final composition satisfactory latherability and/or detergent power, and excessive amounts of surfactants do not really afford any additional advantages. Thus, according to the invention, the total amount of surfactants may represent from 4% to 50% by weight, preferably from 6% to 35% by weight and even more preferentially from 8% to 25% by weight relative to the total weight of the final composition. The sulfate or sulfonate anionic surfactant/amphoteric surfactant weight ratio preferably ranges from 0.1 to 2, more particularly from 0.5 to 1 and even more preferentially from 0.7 to 0.8. The sulfate or sulfonate anionic surfactant/carboxylic anionic surfactant weight ratio preferably ranges from 0.1 to 10, . even more preferentially from 0.5 to 5 and better still from 1 to 3. The carboxylic anionic surfactant/amphoteric surfactant weight ratio preferably ranges from 0.1 to 10, even more preferentially from 0.2 to 5 and better still from 0,3 to 2. The cosmetic composition according to the invention comprises one or more cationic polymers whose cationic charge density is greater than 4 milliequivalents per gram (meq./g), preferably greater than or equal to 5 milliequivalents per gram (meq./g), preferably ranging from 5 to 20 meq./g and more particularly from 5.5 to 10 meq./g. The cationic charge density of a polymer corresponds to the number of moles of cationic charges per unit of mass of polymer under conditions in which this polymer is totally ionized. It may be determined by calculation if the structure of the polymer is known, i.e. the structure of the monomers constituting the polymer and their molar or weight proportion. It may also be determined experimentally via the Kjeldahl method, generally at pH of about 7 at room temperature. The cationic polymers with a caticnic charge density of greater than or equal to 4 meq/g that may be used in accordance with the present invention may be chosen from all those already known per se as improving the cosmetic properties of the hair treated with compositions, i.e. especially those described in patent application EP-A-0 337 354 and in French patent applications FR-A-2 270 846, 2 383 660, 2 598 611, 2 470 596 and 2 519 863. In general, for the purposes of the present invention, the term "cationic polymer" denotes any polymer comprising cationic groups and/or groups that may be ionized into cationic groups. The cationic polymers are chosen from those containing units comprising primary, secondary, tertiary and/or quaternary amine groups that either may form part of the main polymer chain or may be borne by a side substituent directly attached thereto. The cationic polymers used generally have a number- average molecular mass of between 500 and 5 x 106 approximately and preferably between 103 and 3 x 10e approximately. Among the cationic polymers that may be mentioned more particularly are polymers of the polyamine, polyamino amide and polyquaternary ammonium type. These are known products. Among these polymers, mention may be made of; (1) homopolymers or copolymers derived from acrylic or methacrylic esters or amides and comprising at least one of the units of the following formulae: (Formula Removed) i n whi ch: R3, which may be identical or different, denote a hydrogen atom or a CH3 radical,; A, which may be identical or different, represent a linear or branched alkyl group of 1 to 6 carbon atoms, preferably 2 or 3 carbon atoms, or a hydroxyalkyl group of 1 to 4 carbcn atoms; R4, R5 and R6, which may be identical or different, represent an alkyl group containing from 1 to 18 carbon atoms or a benzyl radical and preferably an alkyl group containing from 1 to 6 carbon atoms; R1 and R2, which may be identical or different, represent hydrogen or an alkyl group containing from 1 to 6 carbon atoms, and preferably methyl or ethyl; X" denotes an anion derived from a mineral or organic acid, such as a methosulfate anion or a halide such as chloride or bromide. The copolymers of family (1) can also contain one or more units derived from com.onomers that may be chosen from the family of acrylamides, methacrylamides, diacetone acrylamides, acrylamides and methacrylamides substituted on the nitrogen with lower (C1-C4) alkyls, acrylic or methacrylic acids or esters thereof, vinyllactams such as vinyipyrrolidone or vinylcapro-lactam, and vinyl esters. Thus, among these copolymers of fanily (1), mention may be made of: - copolymers of acrylamide and of dimethylaminoethyl methacrylate quaternized with dimethyl sulfate or with a dimethyl halide, - the copolymers of acrylamide and of methacryloyloxy-ethyltrimethylammonium chloride described, for example, in patent application EP-A-080 976, ~ the copolymer of acrylamide and of methacryloyloxy-ethyltrimethylammordum methosulfate, - quaternized or nonquaternized vinyipyrrolidone/ dialkylaminoalkyl acrylate or methacrylate copolymers. These polymers are described in detail in French patents 2 077 143 and 2 393 573, - dimethylaminoethyl methacrylate/vinylcaprolactam/ vinyipyrrolidone terpolymers, - vinyipyrrolidone/methacrylamidopropyldimethylamine copolymers, - and quaternized vinylpyrrolidone/dimethylaminopropyl-methacrylamide copolymers. (2) cationic polysaccharides, especially cationic celluloses and cationic galactomannan gums. Among the cationic polysaccharides "hat may be ir.entioned more particularly are cellulose ether derivatives comprising quaternary ammonium groups, cationic cellulose copolymers or cellulose derivatives grafted with a water-soluble quaternary ammonium monomer and cationic galactomannan gums. (3) polymers consisting of piperazinyl units and of divalent alkylene or hydroxyalkylene radicals containing straight or branched chains, optionally interrup-ed by oxygen, sulfur or nitrogen atoms or , by aromatic or heterocyclic rings, and also the oxidation and/or quaternization products cf these polymers. (4) water-soluble polyamino amides prepared in particular by polycondensation of an acidic compound with a polyamine; these polyamino amides can be crosslinked with an epihalohydrin, a diepoxide, a dianhydride, an unsaturated dianhydride, a bis-unsaturated derivative, a bis-halohydrin, a bis-azetidinium, a bis-haloacyldiamine, a bis-alkyl halide or alternatively with an oligomer resulting from the reaction of a difunctional compound which is reactive with a bis-halohydrin, a bis-azetidinium, a bis-haloacyldiamine, a bis-alkyl halide, an epihalohydrin, a diepoxide or a bis-unsaturated derivative; the crosslinking agent being used in proportions ranging from 0-02 5 to 0.35 mol per amine group of the polyamino amide; these polyamino amides can be alkylated or, if they contain one or more tertiary amine functions, they can be quaternized. (5) polyaninoamide derivatives resulting from the condensation of polyalkylene polyamines with polycarboxylic acids followed by alkylation with difunctional agents. Mention may be made, for example, of adipic acid/dialkylaminohydroxyalkyldialkylene- triamine polymers in which the alkyl radical contains from 1 to 4 carbon atoms and preferably denotes methyl, ethyl or propyl. Among these derivatives, mention may be made more particularly of the adipic acid/dimethylaminohydroxy-prcpyl/diethyienetriamine polymers. (6) polymers obtained by reaction of a oolyalkylene polyamine containing two primary amine groups and at least one secondary amine group with a dicarboxylic acid chosen from diglycolic acid and saturated aliphatic dicarboxylic acids containing from 3 to 8 carbon atoms. (7) cyclopolymers of alkyldiallylamine or of dialkyl-diallylarunonium, such as the homopolymers or copolymers con-aining, as main constituent of the chain, units corresponding to formula (5) or (5' ) : (Formula Removed) in which formulae k and t are equal to 0 or 1, the sum k + t being equal to 1; R12 denotes a hydrogen atom or a methyl radical; Rio and Rn, independently of each other, denote an alkyl group having from 1 to 6 carbon atoms, a hycro'xyalkyl group in which the alkyl group preferably has 1 to 5 carbon atoms, a lower (C1-C4) anidoalkyl group, or R10 and R11 can denote, together with the nitrogen atom to which they are attached, heterocyclic groups such as piperidyl or morphclinyl; Y" is an anion such as bromide, chloride, acetate, borate, citrate, tartrate, bisulfate, bisulfite, sulfate or phosphate. These polymers are described in particular in French patent 2 080 759 and in its Certificate of Addition 2 190 406. R10 and R11, independently of each other, preferably denote an alkyl group containing from 1 to 4 carbon atoms. Among the polymers defined above, mention may be made more particularly of the dimethyldiallylammonium chloride homopolymers sold especially, under the name Merquat 100 by the company Nalco (and its homologs of low weight-average molar mass) and copolymers of diallyldimethylammonium chloride and of acrylamide. (8) quaternary diammonium. polymers containing repeating units corresponding to the formula: (Formula Removed) in which formula (6); R13, R14, R15 and R16, which may be identical or different, represent aliphatic, alicyclic PIT arylaliphatic radicals containing from 1 to 20 carbon atoms or lower hydroxyalkylaliphatic radicals such as hydroxyethyl, or alternatively Ri3/ Rj,«, Ris and R16/ together or separately, constitute, with the nitrogen atoms to which they are attached, heterocycles optionally containing a second heteroatom other than nitrogen, or alternatively R13, R14, R15 and R16 represent a linear or branched C1-C6 alkyl radical substituted with a nitrile, ester, acyl or amide group or a group -C0-0-R17-D or -CO-NH-R17-D where R17 is an alkylene and D is a quaternary ammonium group; A1 and B1 represent polymethylene groups containing from 2 to 20 carbon atoms, which groups may be linear or branched, saturated or unsaturated, and which may contain, linked to or intercalated in the main chain, one or more aromatic rings or one or more oxygen or sulfur atoms or sulfoxide, sulfone, disulfide, amino, alkylamino, hydroxyl, quaternary ammonium, ureido, amide or ester groups, and X" denotes an anion derived from a mineral or organic acid; A1, R13 and R15 can form, with the two nitrogen atoms to which they are attached, a piperazine ring; in addition, if A1 denotes a linear or branched, saturated or unsaturated alkylene or hydroxyalkylene radical, B1 can also denote a group (CH2) n-C0-D-0C-(CH2)n-; in which D denotes: a) a glycol residue of formula: -0-Z-0-, where Z denotes a linear or branched hydrocarbon-based radical or a group corresponding to one of the following formulae: (Formula Removed) where x and y denote an integer from 1 to 4, representing a defined and unique degree of polymerization or any number from 1 to 4 representing an average degree of polymerization; b) a bis-secondary diamine residue such as a piperazine derivative; c) a bis-primary diamine residue of formula: -NH-Y-NH-, where Y denotes a linear or branched hydrocarbon-based radical, or alternatively the divalent radical (Formula Removed) d) a ureylene group of formula; -NH-C0-NH-; Preferably, X- is an anion such as chloride or bromide. These polymers generally have a number-average molar mass of between 1000 and 100 000. It is more particularly possible to use polymers that consist of repeating units corresponding to the formula: (Formula Removed) in which R1, R2, R3 and R4, which may be identical or different, denote an alkyl or hydroxyalxyl radical containing from 1 to 4 carbon atoms approximately, n and p are integers ranging from 2 to 20 approximately, and X" is an anion derived from a mineral or organic acid. One compound of formula (a) which is particularly preferred is the one for which R=, R2, R= and R4 represent a methyl radical and n = 3, p = 6 and X = Cl, which is known as Hexadiraethrine chloride according to the INCI (CTFA) nomenclature. (9) polyquaternary ammonium polymers consisting of units of formula (7): (Formula Removed) in which formula: R18, R19, R2o and R21, which may be identical or different, represent a hydrogen atom or a methyl, ethyl, propyl, p-hydroxyethyl, ß-hydroxypropyl or -CH2CH2{OCH2CH2)pOH radical, where p is equal to 0 or to an integer between 1 and 6, with the proviso that R18, R19, R20 and R21 do not simultaneously represent a hydrogen atom, r and s, which may be identical or different, are integers between 1 and 6, q is equal to 0 or to an integer between 1 and 34, x- denotes an anion such as a halide, A denotes a dihalide radical or preferably represents -CH2-CH2-O-CH2-CH2- Such compounds are described in particular in patent application EP-A-122 324. Examples that may be mentioned' include the products Mirapol® A15, Mirapol® AD1, Mirapol® AZl and Mirapol® 175. sold by the company Miranol. (10) quaternary polymers of vinyllactam (vinylpyrrolidone and/or vinylcaprolactam) and of vinylimidazole. (11) crosslinked polymers of methacryloyloxy(C1- C4) alkyltri (C1-C4) alkylammonium salts, such ' as the polymers obtained by homopolymerization of dimethylaminoethyl methacrylate quaternized with methyl chloride, or by copolymerization cf acrylamida with dimethylaminoethyl methacrylate quaternized with methyl chloride, the homo- or copolymerization being followed by crosslinking with a corapound containing olefinic unsaturation, in particular methylenebisacrylamide. Other cationic polymers that can be used in the context of the invention are cationic proteins or cationic protein hydrolysates, polyalkyleneimines, in particular polyethyleneimines, polymers containing vinylpyridine or vinylpyridinium units, condensates of polyamines and of epichlorohydrin, quaternary polyureylenes and chitin derivatives. Among these cationic polymers, those of families (1), (7), (8), (9) and (10) are preferably used. Among all the cationic polymers that may be used in the context of the present invention, cationic cyclcpolymers are preferably used, in particular the dimethyidiallylarrauonium chloride homopolymers sold under the name Merquat 100 by the company Nalco, diquaternary ammonium polymers and polyethyleneimines, and mixtures thereof. The cationic polymer(s) with a cationic density of greater than 4 meq./g is (are) generally present in amounts ranging from 0.01% to 20% by weight, preferably from 0.05% to 10% by weight, more particularly from 0.1% to 5% by weight and better still from 0.2% to 2% by weight relative to the total weight of the composition. Said agent that is beneficial to keratin materials may be chosen from: (1) hydrolyzed or nonhydrolyzed, modified or unmodified saccharides, oligosaccharides and polysaccharides, (2) hydrolyzed or nonhydrolyzed, modified or unmodified amino acids, oligopeptides, peptides and proteins, (3) branched or unbranched fatty acids and alcohols, (4) animal, plant or mineral waxes, (5) ceramides and pseudoceramides, (6) hydroxylated organic acids, (7) UV-screening agents, (8) antioxidants and free-radical scavengers, (9) chelating agents, (10) antidandruff agents, (11) seborrhea regulators, (12) calmatives, (13) cationic surfactants, (14) organomodified or non-organomodified silicones, (15) mineral, plant or animal oils, (16) polyiscbutenes and poly (α-olef ins) , (17) fatty esters, preferably containing from 15 to 50 carbon atoms, (18) soluble or dispersed anionic polymers, (19) soluble cr dispersed nonionic polymers, and mixtures thereof. The composition according to the invention may comprise one or more identical or different, hydrolyzed or nonhydrolyzed, modified or unmodified saccharides, oligosaccharides or polysaccharides. In general, the compounds of this type that may be used in the present invention are chosen from those described especially in Kirk-Othmer's *Encyclopedia of Chemical Technology", Third Edition, 1982, volume 3, pp. 396-900 and volume 15, pp. 439-458, in "'Polymers in Nature" by E.A. MacGregor and C.T. Greenwood, published by John Wiley & Sons, Chapter 6, pp. 240-328, 1980, and in "industrial Gums - Polysaccharides and their Derivatives'', edited by Roy L. Whistler, Second Edition, published by Academic Press Inc., the content of these three publications ' being included in their entirety in the present patent application by reference. As examples of modified or unmodified, optionally hydrolyzed saccharides, oligosaccharides and poly¬saccharides that may be used in the invention, mention may be made especially of glucans, modified or unmodified starches (such as those derived, for example, from cereals, for instance wheat, corn or rice, from vegetables, for instance haricot beans, from tubers, for instance potato or cassava), other than the starch betainate as described above, amylose, amylopectin, glycogen, dextrans, ß-glucans, celluloses and derivatives thereof (methylcelluloses, hydroxyalkylcelluloses, ethylhydroxyethylcelluloses or carboxymethylcelluloses), fructosans, inulin, levan, mannans, xylans, lignins, arabans, galactans, galacturonans, chitin, glucoronoxylans, arabinoxylans, xyloglucans, galactomanr.ans, glucomannans, pectic acids and pectins, alginic acid and alginates, arabino-galactans, carrageenans, agars, glycosaminoglucans, guir:' arables, gum tragacanths, ghatti gums, karaya gums, carob gums, guar gums and xanthan gums, and mixtures thereof. The composition according to the invention may comprise one or more hydrolyzed or nonhydrolyzed, modified or unmodified amino acids, oligopeptides, peptides or proteins. Examples of amino acids that may be mentioned include cysteine, lysine, alanine, N-phsnylalanine, arginine, glycine and leucine, and mixtures thereof. As modified or unmodified, optionally hydrolyzed oligopeptides, peptides and proteins that may be used according to the invention, mention may be made especially of modified or unmodified wool or silk protein hydrolysates, and plant proteins such as wheat proteins. The composition according to the invention may comprise one or more branched or unbranched fatty acids and alcohols. Among the fatty acids that are suitable for use in the present invention, mention may be made especially of C5-C30 carboxylic acids such as palmitic acid, oleic acid, iinoleic acid, myristic acid, stearic acid and lauric acid, and mixtures thereof. The fatty alcohols that may be used in the present invention especially include C8-C30 alcohols such as, for example, palmityl alcohol, oleyl alcohol, linoleyl alcohol, rnyristyl alcohol, stearyl alcohol and lauryl alcohol, ana mixtures thereof. The composition according to the invention may comprise one or more animal, plant or mineral waxes. For the purposes of the present invention, a wax is a lipophilic compound that is solid at room temperature (about 25°C), with a reversible solid/liquid change of state, having a melting point of greater than about 40°C and which may be up to 200°C, and having an anisotropic crystal organization in the solid state. In general, the size of the wax crystals is such that crystals scatter and/or diffuse light, giving the composition comprising them a more or less opaque, cloudy appearance. By raising the wax to its melting point,, it is possible to make it miscible with oils end to form a microscopically homogeneous mixture, but on returning the temperature of the mixture to room temperature, a microscopically and macroscopically detectable recrystallization of the wax in the oils of the mixture is obtained (opalescence). As waxes that may be used in the present invention, mention may be made of waxes of animal origin such as beeswax, spermaceti, lanolin wax and lanolin derivatives; plant waxes such as carnauba wax, car.delilla wax, ouricury wax, Japan wax, cocoa butter, cork fiber wax or sugar cane wax; mineral waxes, for example paraffin wax, petroleum jelly wax, lignite wax, microcrystalline waxes or ozokerites, and mixtures thereof. The composition according to the invention may comprise one or more ceramides and/or pseudoceramides. Mention may be made in particular of the ceramides of categories I, II, III and V according to the Dawning classification, and mixtures thereof, and more particularly N-oleyldehydrosphingosine. The composition according to the invention may comprise one or more hydroxylated organic acids chosen from these that are well known and used in the art. Mention may be made especially of citric acid, lactic acid, tartaric acid and malic acid, and mixtures thereof. The composition according to the invention may comprise one or more UV-A-active and/or UV-B-active sunscreens that are well known to those skilled in the art. Mention may be made especially of dibenzoylmethane derivatives such as 4-rr.ethyldibenzoylmethane, 4-isopropyldibenzoylmethane, 4-tert-butyldibenzoyl-methane, 2, 4-dimethyldibenzoylmethane, 4-tert-butyl-4' -diisopropyldibenzoylrrethane, p-aminobenzoic acid and its esters such as 2-ethylhexyl p-dimethylaminobenzoate and N-propoxylated ethyl p-aminobenzoate, salicylates such as triethanolamine salicylate, cinnamic acid esters such as 2-etr,ylhexyl 4-methoxycinnamate, methyl diisopropylcinnamate, menthyl anthranilate, benzotriazole derivatives, triazine derivatives, (3,PX-diphenylacrylate derivatives such as 2-ethylhexyl 2-cyano-3,3-diphenylacrylate and ethyl 2-cyano~3,3-diphenylacrylate, 2-phenylbenzimidazole-5-sulfcnic acid and its salts, benzophenone derivatives, benzyl idenecainphcr derivatives, silicone screening agents, etc., and mixtures thereof As examples of antioxidants and free-radical scavengers that may be used in the present invention, mention way be made of ascorbic acid, ascorbyl compounds such as ascorbyl dipalmitate, t-butylhydroquinone, polyphenols such as phloroglucinol, sodium sulfite, erythorbic acid and flavonoids, and mixtures thereof. The composition according to the invention may comprise one ox more chelating agents chosen especially from EDTA (ethyienediaminetetraacetic acid) and salts thereof such as disodiuxn EDTA and dipotassium EDTA, phosphate compounds such as sodium netaphosphate, sodium hexametaphosphate and tetrapotassium pyrophosphate, and phosphonic acids and salts thereof, such as ethylenediaminetetramethylenephosphonic acid salts, and mixtures thereof. The composition according to the invention may comprise one or more antidandruff agents chosen, for example, from: -benzethonium chloride, benzalkonium chloride, chlorhexidine, chlcramine T, chlorarnine B, 1,3-dibromo-5,5-dimethylhydantoin, 1,3-dichloro-5,5-dimethy-hydantoin, 3-bromo-l-chloro-5,5-dimethyl¬hydantoin and N-chlorosuccmimide; l-hydroxy-2-pyridone derivatives such as, for example, l-hydroxy-4-methyl-2-pyridone, 1-hydroxy- 6-methyl-2-pyridone and 1-hydroxy-4,6-dimethyl-2- pyridone; trihalocarbamides; triclosan; azole compounds such as climbazole, ketoconazole, clotrimazole, econazole, isoconazole and miconazole b; antifungal polymers such as amphotericin B or nystatin; selenium sulfides; sulfur in its various forms, cadmium sulfide, allantoin, coal tar or wood tar and in particular derivatives thereof, cade oil, undecylenic acid, fumaric acid and allylamines such as terbinafine; or a mixture of these antidandruff agents. Said agents may also be used in the form of the addition salts thereof with physiologically acceptable acids, especially in the form of the sulfuric acid, nitric acid, thiocyanic acid, hydrochloric acid, hydrobromic acid, hydriodic acid, phosphoric acid, acetic acid, benzoic acid, glycolic acid, aceturic acid, succinic acid, nicotinic acid, tartaric acid, maleic acid, palmitic acid, methanesulfonic acid, propanoic acid, 2-oxopropanoic acid, propanedioic acid, 2-hydroxy-l,4-butanedioic acid, 3-phenyl-2-propenoic acid, a-hydroxybenzeneacetic acid, ethanesulfonic acid, 2-hydroxyethanesulfonic acid, 4-methylbenzenesulfonic acid, 4-amino-2-hydroxybenzoic acid, 2-phenoxybenzoic acid, 2-acetyloxybenzoic acid, picric acid, lactic acid, citric acid, malic acid, oxalic acid and amino acid salts. The antidandruff agents mentioned above may also, where appropriate, be used in the form of the addition salts thereof with physiologically acceptable organic or mineral bases. Examples of organic bases are especially low molecular weight alkanolamines such as ethanol-amine, diethanolamine, N-ethylethanolamine, triethanol- amine, diethylaminoethanol and 2-amino-2~methylpropane-dione; nonvolatile bases such as ethylenediamine, hexamethylenediamine, cyclohexylamine, benzylamine and N-iuethylpiperazina; quaternary ammonium hydroxides, for example trimethylbenzyl hydroxide; guanidine and its derivatives, and particularly its alkyl derivatives. Examples of mineral bases are especially the alkali metal salts, for instance the sodium or potassium salts; the ammonium salts, the alkaline-earth metal salts, for instance the magnesium or calcium salts; the salts of cationic di~, tri- or tetravalent metals, for instance the zinc, aluminum and zirconium salts. Alkanolamines, ethylenediamine and mineral bases such as the alkali metal salts are preferred. The composition according to the invention may comprise one or more seborrhea regulators such as succinyl-chitossn and poly-ß-alanine, and mixtures thereof. The composition according to the invention may comprise one or more calmatives such as azulene and glycyrrhetinic acid, and mixtures thereof. The composition according to the invention may comprise one or more cationic surfactants that are well known per se, such as optionally polyoxyalkylenated primary, secondary or tertiary fatty amine salts; quaternary ammonium salts such as tetraalkylammonium, alkylamido-alkyltrialkylairmonium, trial kylbenzylawmonium, tri-alkylhydroxyalkylammonium or alkylpyridinium chlorides or bromides; imidazoline derivatives; or amine oxides of cationic nature. The silicones that may be used in accordance with the invention may be soluble or insoluble in the composition, and they may be in particular polyorgano-siloxanes that are insoluble in the composition of the invention. They may be in the form of oils, waxes, resins or gums. The organopolysiloxar.es are defined in greater detail in Walter Noll's "Chemistry and Technology of Silicones" (1968) Academic Press. They can be volatile or nonvolatile. When they are volatile, the silicones are more particularly chosen from those having a boiling point of between 60°C and 2 60oC, and. even more particularly from: (i) cyclic silicones containing from 3 to 1 and preferably 4 to 5 silicon atoms. These are, for example, octamethylcyclotetrasiloxane sold in particular under the name Volatile Silicone 7207 by Union Carbide or Silbione 70045 V 2 by Rhodia, decamethylcyclopentasiloxane sold under the name Volatile Silicone 7158 by Union Carbide, and Silbione 70045 V 5 by Rhodia, and mixtures thereof. Mention may also be made of cyclocopolymers of the dimethylsiloxane/methylalkylsiloxane type, such as Volatile Silicone FZ 3109 sold by the company Union Carbide, having the chemical structure: (Formula Removed) Mention may also be made of mixtures of cyclic silicones with organosilicon compounds, such as the mixture of octamethylcyclotetrasiloxane and tetratrimethylsilylpentaerythritol (50/50) and . the mixture of octamethylcyclotetrasiloxane and oxy-1,1'-bis(2,2,2',2',3,3'-hexatrimethylsilyloxy)neopehtane; (ii) linear volatile silicones containing 2 to 9 silicon atoms and having a viscosity of less than or equal to 5 x 10-6 mz/s at 25°C. An example is decamethyltetrasiloxane sold in particular , under the name SH 200 by the company Toray Silicone. Silicones belonging to this category are also described in the article published in Cosmetics and Toiletries, Vol. 91, Jan. 76, pp. 27-32, Todd & Byers . "Volatile silicone Fluids for Cosmetics". Among the nonvolatile silicones that ir.ay especially be mentioned are polyalkylsiloxanes, polyarylsiloxanes, polyalkylarylsiloxanes, silicone gums and resins, polyorganosiloxanes modified with organofunctional groups, and also mixtures thereof. The. organomodified silicones that can be used in accordance with the invention are silicones as defined above and containing in their structure one or more organofunctional groups attached via a hydrocarbon-based group. Among the organomodified silicones, mention may be made of polyorganosiloxanes comprising: - polyethyleneoxy and/or polypropyleneoxy groups optionally comprising C6-C24 alkyl groups, such as the products known as ditnethicone copolyol sold by the company Dow Corning under the name DC 1248 or,the oils Silwet® L 722, L 7500, L 77 and L 711 by the company Onion Carbide, and the (C12)alkylmethicone copolyol sold by the company Dow Coming under the name Q2 52 00; - substituted or unsubstituted axrdne groups, such as the products sold under the name GP 4 Silicone Fluid and GP 7100 by the company Genesee, or the products sold under the names Q2 8220 and Dow Corning 929 or 939 by the company Dow Corning. The substituted amine groups are, in particular,C1-C4aminoalkyl groups; - thiol groups, Such as the products sold under the names "GP 72 A" and "GP 71" from Genesee; - alkoxylated groups, such as the product sold under the name "Silicone Copolymer F-7 55" by SWS Silicones and Abil Wax® 2428, 2434 and 2440 by the company Goldschmidt; - hydroxylated groups, such as the polyorganosiloxanes containing a hydroxyalkyl function, described in French patent application FR-A-85/16334; - acyloxyalkyl groups, such as, for example, the polyorganosiloxanes described in patent US-A-4 957 732; ~ anionic groups of the carboxylic acid type, such as, for example, in the products described in patent EP 186 507 from the company Chisso Corporation, or of the alkylcarboxylic type, such as those present in the product X-22-3701E from the company Shin-Etsu; 2-hydroxyalkyl sulfonate; 2-hydroxyalkyl thiosulfate such as the products sold by the company Goldschmidt under the names vAbil® S201" and "Abil® S255"; - hydroxyacylamino groups, such as the polyorganosiloxanes described in patent application EP 342 834. Mention may be made, for example, of the product Q2-8413 from the company Dow Corning. The composition according to the invention may comprise one or more mineral, plant or animal oils. Oils of plant origin that may especially be mentioned include sweet almond oil, avocado oil, castor oil, olive oil, jojoba oil, sunflower oil, wheatgerm oil, sesame seed oil, groundnut oil, grapeseed oil, soybean oil, rapeseed oil, safflower oil, coconut oil, corn oil, hazelnut oil, shea butter, palm oil, apricot kernel oil and beauty-leaf oil; an oil cf animal origin that may be mentioned is perhydrosqualene; oils of mineral origin that may be mentioned include liquid paraffin and liquid petroleum jelly; and mixtures thereof. The composition according to the invention may comprise one or more polyisobutenes and poly(α-olefins), chosen from those that are well known in the art. The composition according to the invention, may comprise one or more esters. Examples of asters that may especially be mentioned are fatty acid esters preferably containing from 8 to 22 carbon atoms, for instance isopropyl myristate, isopropyl palraitate, 2-ethylhexyl palmitate, purcellin oil (stearyl octanoate), isononyl isononanoate, isostearyl iso.nonanoate and isopropyl lanolate, and mixtures thereof. Mention may also be made especially of fatty alkyl esters preferably containing from 8 tc 22 carbon atoms. The composition according to the invention may comprise one or more soluble or dispersed anionic polymers that are well known per se. The anionic polymers generally used in the present invention are polymers comprising groups derived from carboxylic acids,. sulfonic acids or phosphoric acids, and having a weight-average molecular mass of between 500 and 5 000 000. The carboxylic groups are provided by unsaturated monocarboxylic or dicarboxylic acid monomers such as those corresponding to the formula: (Formula Removed) in which n is an integer from 0 to 10, A denotes a methylene group, optionally connected to the carbon atom of the unsaturated group or to the neighboring methylene group when n is greater than 1 via a heteroatom such as oxygen or sulfur, R1 denotes a hydrogen atom or a phenyl or benzyl group, R2 denotes a hydrogen atom or a lower alkyl or carboxyl group, and R3 denotes a hydrogen atom, a lower alkyl group or a -CH2-COOH, phenyl or benzyl group. In formula (8) above, a lower alkyl group preferably contains from 1 to 4 carbon atoms and in particular denotes methyl and ethyl groups. The anionic polymers containing carboxylic groups that are preferred according to the invention are: A) homo- or copolymers of acrylic or methacrylic acid or salts thereof and in particular the products sold under the names Versicol® E or K by the company Allied Colloid, altrahold® by the company BASF, the copolymers of acrylic acid and acrylamide sold in the form of their sodium salt under the names Reten® 421, 423 or 425 by the company Hercules, and the sodium salts of polyhydroxycarboxylic acids; B) copolymers of acrylic or methacrylic acids with a raonoethylenic monomer such as ethylene, styrene, vinyl esters and acrylic or methacrylic acid esters, optionally grafted onto a polyalkylene glycol such as polyethylene glycol and optionally crosslinked. Such polymers are described in particular in French patent 1 222 944 and German patent application No. 2 330 956. Mention may be made in particular of copolymers whose chain comprises an optionally N-alkylated and/or hydroxyalkylated acrylamide unit, such as those described in particular in the Luxembourg patent applications 75370 and 75371 or sold under the narce Quadramer® by the company American Cyanamid. Mention may also be made of copolymers of acrylic acid and of C1-C4 alkyl