WO2017097849A1

WO2017097849A1 - Composition comprising a polymer containing a sulfonic monomer and a pyridinedicarboxylic acid derivative, and cosmetic treatment method

Info

Publication number: WO2017097849A1
Application number: PCT/EP2016/080119
Authority: WO
Inventors: Laurence Richet; Olivia ISARD
Original assignee: L'oreal
Priority date: 2015-12-08
Filing date: 2016-12-07
Publication date: 2017-06-15
Also published as: JP6991971B2; FR3044548A1; JP2018536673A; FR3044548B1; EP3386476A1

Abstract

The present invention relates to a composition comprising water, a polymer comprising at least one monomer containing a sulfonic group and a compound of general formula (I) or a salt thereof: in which R₁ and R₂ represent, independently of one another, a hydrogen atom, a saturated or unsaturated, linear or branched C₁-C₁₈ aliphatic hydrocarbon radical; or a C₆-C₁₈ aryl radical; at least one of the R₁ and R₂ groups being other than a hydrogen atom. The invention also relates to a method for the cosmetic treatment of keratin materials, in particular the hair and/or the scalp, using said composition.

Description

Composition comprising a polymer containing a sulfonic monomer and a pyridinedicarboxylic acid derivative, and cosmetic treatment method

The present invention relates to a composition, in particular a cosmetic composition, comprising a pyridinedicarboxylic acid derivative in combination with a particular thickening polymer, and also to a cosmetic treatment method using said composition, in particular in the field of haircare. The growth of the hair and its renewal are mainly determined by the activity of the hair follicles and their matrix environment. Their activity is cyclical and essentially comprises three phases, namely the anagenic phase, the catagenic phase and the telogenic phase. The head of hair is continuously renewed and, of the approximately 150 000 individual hairs which make up a head of hair, approximately 10% are at rest and will be replaced in the months to come. The natural loss of the hair can be estimated, on average, at a few hundred hairs per day for a normal physiological state. This constant physical renewal process undergoes a natural change during the course of ageing; the hairs become finer and their cycles shorter. It is known, furthermore, that certain factors, such as hormonal imbalance, physiologi- cal stress or malnutrition, can accentuate the phenomenon. In addition, loss or impairment of the hair can be in connection with seasonal phenomena.

It has thus in particular been proposed, by patent EP 1 352 629, to use pyridinedicarboxylic acid derivatives to induce and/or stimulate the growth of human keratin fibres, such as the hair or eyelashes, and/or to slow down their loss and/or to in- crease their density.

These derivatives are generally offered formulated in the form of an aqueous- alcoholic lotion to be applied to the scalp.

However, the need to have thickened compositions, in particular aqueous- alcoholic lotions, is emerging.

Specifically, the formulation of these derivatives within a thickened composition especially provides slip, in particular on dry hair, which facilitates the massaging of the scalp, thus enabling a better distribution and a better availability of the active agents on the scalp and throughout the length of the hair.

The fact that the composition is thickened, or even gelled, makes it possible to provide a more slippery feel than that obtained with a non thickened aqueous- alcoholic lotion.

When the composition is thickened, the measuring out thereof is facilitated since it can be drawn off easily, it runs less between the fingers and ultimately there is less loss. In addition, it can be applied to and distributed over the hair or scalp more easily, without running onto the face or neck.

The action is facilitated; specifically, it is then possible to use a pump-action bottle generally intended for serums, rather than pipettes or single-dose containers for example.

Lastly, the thickened composition makes it possible to provide conditioning, volume and density to the head of hair during styling. The hair is smooth and shiny.

In addition, the composition has a better stability, whether this is with respect to temperature, to pH or over time.

The objective of the present invention is therefore to propose a composition that is advantageously in the form of a lotion, in particular hair lotion, which is thickened and stable even though it comprises a pyridinedicarboxylic acid derivative.

A subject of the present invention is a composition comprising:

- (i) at least one compound of general formula (I), or a salt thereof:

in which Ri and F¾ represent, independently of one another, a hydrogen atom, a saturated or unsaturated, linear or branched C1-C18 aliphatic hydrocarbon radical; or a C6-C18 aralkyl radical; said radicals optionally being substituted by one or more groups selected from OH, NH₂, -OR, -OCOR and -NHR with R representing a C1-C18 alkyl group; at least one of the Ri and R2 groups being other than a hydrogen atom; and

- (ii) at least one polymer comprising at least one monomer containing a sulfonic group;

the composition comprising water in an amount ranging from 20% to 80% by weight, or even from 30% to 50% by weight, relative to the total weight of the composition.

Another subject of the invention is a method for the cosmetic treatment of keratin materials, in particular the hair and/or the skin, including the scalp, in which a cosmetic composition as defined above is applied to said keratin materials and said keratin materials are optionally rinsed.

The compositions according to the invention result in a substantial provision of density and volume to the head of hair, during styling, and also a provision of body, the hair being stronger and more resistant. The head of hair is well-behaved, and easy to style. Moreover, the usage and sensory qualities are improved.

The thickened compositions according to the invention are furthermore stable, in particular during storage and/or with respect to temperature variations. In the present description, the expression "at least one" is equivalent to the ex- pression "one or more" and can be substituted therefor, and the expression "between ... and ..." is equivalent to the expression "ranging from ... to ..." and can be substituted therefor; in these two expressions, the limits are included. 1/ Pyridinedicarboxylic acid ester

The composition according to the invention thus comprises at least one pyridinedicarboxylic acid ester. The ester can be a monoester or a diester, preferably a diester. It can also be a salt of such an ester. Said compounds correspond to the general formula (I), or a salt thereof:

in which Ri and R2 represent, independently of one another, a hydrogen atom, a saturated or unsaturated, linear or branched C1-C18 aliphatic hydrocarbon radical, in particular alkyl radical; or a C6-C18 aryl radical; said aliphatic or aryl hydrocarbon radicals optionally being substituted by one or more groups selected from OH, NH₂, -OR, -OCOR and -NHR with R representing a C1-C18 alkyl group;

it being understood that at least one of the Ri and R2 groups is other than a hydrogen atom.

Preferably, the COOR1 and COOR2 substituents are respectively in the 2 and 3 positions, or in the 2 and 4 positions of the pyridine ring. Preferably, they are in the 2 and 4 positions. Preferably, the compounds correspond to the formula (la), or a salt thereof:

in which Ri and R2 represent, independently of one another, a hydrogen atom, a saturated or unsaturated, linear or branched C1-C18 aliphatic hydrocarbon radical, in particular alkyl radical; or a C6-C18 aryl radical; said aliphatic or aryl hydrocarbon radicals optionally being substituted by one or more groups selected from OH, NH₂, -OR, -OCOR and -NHR with R representing a C1-C18 alkyl group; at least one of the Ri and R2 groups being other than a hydrogen atom. Preferably, in the formulae (I) and (la), the C1-C18 aliphatic hydrocarbon radical, in particular alkyl radical, is a C1-C10, in particular C1-C6, aliphatic hydrocarbon radi- cal, in particular alkyl radical, such as methyl, ethyl, tert-butyl, isopropyl or hexyl. Said aliphatic hydrocarbon radical can also comprise at least one carbon-carbon double bond or triple bond, such as, for example, -CH=CH₂, -CH₂-CH=CH-CH₃ and -CH₂-C≡CH.

The aryl radical can represent the phenyl or naphthyl radical.

In particular, in the formulae (I) and (la), Ri and R₂ represent, independently of one another, a hydrogen atom or a saturated, linear or branched, C1 -C18, better still C1 -C10, indeed even C1 -C6, aliphatic hydrocarbon radical, in particular alkyl radical, which is optionally substituted by an alkoxy or acyloxy group (OR or OCOR with R denoting a C1-C18 alkyl radical), at least one of the Ri and R₂ groups being other than a hydrogen atom.

Preferably, Ri and R₂ are identical.

Preferably, Ri and R₂ are identical and represent a saturated linear C1-C18, preferably C1 -C10 and better still C1 -C6 alkyl radical and very particularly an ethyl radical.

Mention may in particular be made of the following compounds of formula (I):

- dimethyl 2,4-pyridinedicarboxylate,

- dimethyl 2,3-pyridinedicarboxylate,

- diethyl 2,4-pyridinedicarboxylate,

- diethyl 2,3-pyridinedicarboxylate,

- diethyl 2,5-pyridinedicarboxylate,

- dimethyl 2,5-pyridinedicarboxylate,

- diisopropyl 2,4-pyridinedicarboxylate,

- di(acetyloxymethyl) pyridine-2,4-dicarboxylate (derivative of formula (I) such that Ri and R₂ represent -CH₂-O-COCH₃).

Preferably, the composition comprises, as compound of formula (I) or (la), diethyl pyridine-2,4-dicarboxylate.

Salts of the compounds of formula (I) is understood to mean, according to the invention, the organic or inorganic salts of a compound of formula (I), these salts being physiologically acceptable. Mention may be made, as inorganic salts, of the sodium or potassium salts and also the zinc (Zn²⁺), calcium (Ca²⁺), copper (Cu²⁺), iron (Fe²⁺), strontium (Sr²⁺), magnesium (Mg²⁺) or manganese (Mn²⁺) salts; the hydroxides, the carbonates and the chlorides. Mention may be made, as organic salts, of the triethanolamine, monoethanolamine, diethanolamine, hexadecylamine, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine and tris(hydroxymethyl)aminomethane salts.

The compounds of formula (I) are known per se; they are in particular described, along with their manufacture, in the patent EP 1 352 629. Preferably, the composition according to the invention comprises the compound(s) of formula (I) in an amount greater than or equal to 0.5% by weight, in particular between 0.5% and 20% by weight, in particular ranging from 3% to 15% by weight and better still ranging from 4% to 10% by weight, relative to the total weight of the composition.

21 Polymer comprising at least one monomer containing a sulfonic group

The composition according to the invention also comprises one or more polymers comprising at least one monomer containing a sulfonic group.

The polymers comprising at least one monomer containing a sulfonic group are preferably water-soluble or water-dispersible. They may be homopolymers or copolymers and can be obtained from at least one ethylenically unsaturated monomer containing a sulfonic group, which may be in free form or partially or totally neutralized form. These polymers may optionally comprise at least one hydrophobic group and then constitute an amphiphilic polymer (or hydrophobic modified polymer).

Preferably, the polymers in accordance with the invention may be partially or totally neutralized with an inorganic base (sodium hydroxide, potassium hydroxide or aqueous ammonia) or an organic base such as monoethanolamine, diethanolamine or triethanolamine, an aminomethylpropanediol, N- methylglucamine, basic amino acids, for instance arginine and lysine, and mixtures of these compounds. They are generally neutralized. In the present invention, the term "neutralized" is intended to mean polymers that are totally or virtually totally neutralized, i.e. at least 90% neutralized.

The polymers used in the composition of the invention generally have a number- average molecular weight (Mn) ranging from 1000 to 20 000 000 g/mol, preferably ranging from 20 000 to 5 000 000 g/mol and more preferentially still from 100 000 to 1 500 000 g/mol.

These polymers according to the invention may be crosslinked or non-crossl inked. The monomers containing a sulfonic group of the polymer used in the composition of the invention are in particular chosen from vinylsulfonic acid, styrenesulfonic acid, (meth)acrylamido(Ci-C22)alkylsulfonic acids, N-(Ci-

C22)alkyl(meth)acrylamido(Ci-C22)alkylsulfonic acids such as undecylacrylamidomethanesulfonic acid, and also partially or totally neutralized forms thereof, and mixtures thereof.

According to a preferred embodiment of the invention, the monomers containing a sulfonic group are chosen from (meth)acrylamido(Ci-C22)alkylsulfonic acids, for instance acrylamidomethanesulfonic acid, acrylamidoethanesulfonic acid, acrylamidopropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2- methacrylannido-2-nnethylpropanesulfonic acid, 2-acrylannido-n-butanesulfonic acid, 2-acrylamido-2,4,4-thnnethylpentanesulfonic acid, 2-methacrylamidododecyl sulfonic acid and 2-acrylamido-2,6-dimethyl-3-heptanesulfonic acid, and also the partially or totally neutralized forms thereof, and mixtures thereof.

More particularly, use is made of a polymer comprising at least one monomer of 2- acrylamido-2-methylpropanesulfonic acid type, and also the partially or totally neutralized forms thereof.

When the polymers are crosslinked, the crosslinking agents may be chosen from the polyolefinically unsaturated compounds commonly used for crosslinking polymers obtained by radical polymerization.

Examples of crosslinking agents that may be mentioned include divinylbenzene, diallyl ether, dipropylene glycol diallyl ether, polyglycol diallyl ethers, triethylene glycol divinyl ether, hydroquinone diallyl ether, ethylene glycol or tetraethylene glycol di(meth)acrylate, trimethylolpropane triacrylate, methylenebisacrylamide, methylenebismethacrylamide, triallylamine, triallyl cyanurate, diallyl maleate, tetraallylethylenediamine, tetraallyloxyethane, trimethylolpropane diallyl ether, allyl (meth)acrylate, allylic ethers of alcohols of the sugar series, or other allyl or vinyl ethers of polyfunctional alcohols, and also the allylic esters of phosphoric and/or vinylphosphonic acid derivatives, or mixtures of these compounds.

According to one preferred embodiment of the invention, the crosslinking agent is chosen from methylenebisacrylamide, allyl methacrylate and trimethylolpropane triacrylate (TMPTA). The degree of crosslinking generally ranges from 0.01 mol% to 10 mol% and more particularly from 0.2 mol% to 2 mol% relative to the polymer.

When the polymers used are homopolymers, they only comprise monomers containing a sulfonic group and, if they are crosslinked, one or more crosslinking agents. These homopolymers are generally crosslinked and neutralized, and they may be obtained according to the preparation process comprising the following steps:

(a) the monomer such as 2-acrylamido-2-methylpropanesulfonic acid in free form is dispersed or dissolved in a solution of tert-butanol or of water and tert-butanol;

(b) the monomer solution or dispersion obtained in (a) is neutralized with one or more mineral or organic bases, preferably aqueous ammonia NH₃, in an amount making it possible to obtain a degree of neutralization of the sulfonic acid functions of the polymer ranging from 90% to 100%;

(c) the crosslinking monomer(s) are added to the solution or dispersion obtained in (b);

(d) a standard free-radical polymerization is performed in the presence of free- radical initiators at a temperature ranging from 10 to 150°C; the polymer precipitating in the tert-butanol-based solution or dispersion.

Preferably, the composition may comprise at least one 2-acrylamido-2- methylpropanesulfonic acid homopolymer comprising, randomly distributed:

a) from 90% to 99.9% by weight of units of general formula (II) below:

in which X⁺ denotes a proton, an alkali metal cation, an alkaline-earth metal cation or the ammonium ion, not more than 10 mol% of the cations X⁺ possibly being protons H⁺; b) from 0.01 % to 10% by weight of crosslinking units originating from at least one monomer containing at least two olefinic double bonds; the weight proportions being defined relative to the total weight of the polymer.

The homopolymers according to the invention that are more particularly preferred comprise from 98% to 99.5% by weight of units of formula (II) and from 0.2% to 2% by weight of crosslinking units.

A polymer of this type that may especially be mentioned is the crosslinked and neutralized 2-acrylamido-2-methylpropanesulfonic acid homopolymer sold by Clariant under the trade name Hostacerin AMPS (CTFA name: ammonium polyacryldimethyltauramide).

The polymer may also be an amphiphilic homopolymer (or hydrophobic modified homopolymer) selected from random amphiphilic 2-acrylamido-2- methylpropanesulfonic acid polymers modified by reaction with a C6-C22 n- monoalkylamine or di-n-alkylamine, such as those described in document WO 00/31 154, which are grafted homopolymers.

When the polymers used are copolymers they may be obtained by polymerization using ethylenically unsaturated monomers containing a sulfonic group and additional ethylenically unsaturated monomers, i.e. ethylenically unsaturated monomers without a sulfonic group. The ethylenically unsaturated monomers containing a sulfonic group are chosen from those described above.

The ethylenically unsaturated monomers without a sulfonic group may be chosen from ethylenically unsaturated hydrophilic monomers, ethylenically unsaturated hydrophobic monomers and mixtures thereof.

The ethylenically unsaturated hydrophilic monomers may be selected for example from (meth)acrylic acids, β-substituted alkyl derivatives thereof or esters thereof obtained with monoalcohols or monoalkylene or polyalkylene glycols, (meth)acrylamides, vinylpyrrolidone, vinylformamide, maleic anhydride, itaconic acid, maleic acid or mixtures of these compounds.

When the polymer comprising at least one monomer containing a sulfonic group according to the invention is a copolymer that can be obtained from ethylenically unsaturated monomers containing a sulfonic group and ethylenically unsaturated hydrophilic monomers, said polymer may be selected from:

- (1 ) crosslinked anionic copolymers of acrylamide or methacrylamide and of 2- acrylamido-2-methyl-propanesulfonic acid, especially those in the form of a W/O emulsion, such as those sold under the name Sepigel 305 by SEPPIC (INCI name: Polyacrylamide/C13-14 lsoparaffin/Laureth-7), under the name Simulgel 600 by SEPPIC (INCI name: Acrylamide/Sodium acryloyldimethyltaurate copolymer/lsohexadecane/Polysorbate 80);

- (2) copolymers of (meth)acrylic acid or of (meth)acrylate and of 2-acrylamido-2- methylpropanesulfonic acid, especially those in the form of a W/O emulsion, such as those sold under the name Simulgel NS by SEPPIC (copolymer of sodium acrylamido-2-methylpropanesulfonate/hydroxyethyl acrylate as a 40% inverse emulsion in Polysorbate 60 and squalane) (INCI name: Hydroxyethyl acrylate/Sodium acryloyldimethyltaurate copolymer/Squalane/Polysorbate 60), or those sold under the name Simulgel EG by SEPPIC (copolymer of acrylic acid/acrylamido-2-methylpropanesulfonic acid in the form of a sodium salt, as a 45% inverse emulsion in isohexadecane/water) (INCI name: Sodium Acrylate/Sodium acryloydimethyltaurate copolymer/lsohexadecane/Polysorbate 80), or else those sold under the name Sepinov EMT 10 by SEPPIC (INCI name: Hydroxyethyl acrylate/Sodium acryloyldimethyltaurate copolymer); and

- (3) copolymers of 2-acrylamido-2-methylpropanesulfonic acid and of vinylpyrrolidone or vinylformamide, such as the products sold under the names Aristoflex AVC by Clariant.

Preferably, said polymer comprising at least one monomer containing a sulfonic group is selected from those from the families (1 ) to (3) above.

Preferably, said polymer comprising at least one monomer containing a sulfonic group is selected from non-associative polymers. When the polymer comprising at least one monomer containing a sulfonic group according to the invention is a copolymer that can be obtained from ethylenically unsaturated monomers containing a sulfonic group and ethylenically unsaturated hydrophobic monomers, that is to say comprising a C6-C50 fatty chain, said polymer is amphiphilic, that is to say that it comprises both a hydrophilic portion and a hydrophobic portion. Such polymers are also referred to as hydrophobic modified polymers.

These hydrophobic modified polymers may also contain one or more monomers comprising neither a sulfonic group nor a fatty chain, such as (meth)acrylic acids, β-substituted alkyl derivatives thereof or esters thereof obtained with monoalcohols or monoalkylene or polyalkylene glycols, (meth)acrylamides, vinylpyrrolidone, vinylformamide, maleic anhydride, itaconic acid or maleic acid, or mixtures of these compounds.

As polymers comprising at least one monomer containing a sulfonic group according to the invention, use may be made especially of those capable of being obtained from 2-acrylamido-2-methylpropanesulfonic acid and at least one ethylenically unsaturated hydrophobic monomer comprising at least one group containing from 6 to 50 carbon atoms, preferentially from 6 to 22 carbon atoms, better still from 8 to 18 carbon atoms and more particularly 12 to 18 carbon atoms.

The ethylenically unsaturated hydrophobic monomers may be selected from those of formula (III) below:

CH₂ C

O= C

Y ,-CH(R₃)-O in which Ri and R3, which may be identical or different, denote a hydrogen atom or a linear or branched C1-C6 alkyl radical, preferably methyl; Y denotes O or NH; R₂ denotes a hydrocarbon radical comprising from 6 to 50 carbon atoms, preferentially from 6 to 22 carbon atoms, better still from 6 to 18 carbon atoms and more particularly from 12 to 18 carbon atoms; and x varies from 0 to 100.

The R2 radical is preferably selected from linear C6-C18 alkyl radicals (for example n-hexyl, n-octyl, n-decyl, n-hexadecyl, n-dodecyl or lauryl, or n-octadecyl or stearyl radicals); branched or cyclic C6-C18 alkyl radicals (for example cyclododecane (C12) or adamantane (C10) radicals); C6-C18 alkylperfluoro radicals (for example the group of formula -(CH₂)2-(CF₂)9-CF₃); the cholesteryl (C27) radical or a cholesterol ester residue, such as the cholesteryl oxyhexanoate group; or polycyclic aromatic groups, such as naphthalene or pyrene. Among these radicals, the ones that are more particularly preferred are substantially linear alkyl radicals and more particularly the n-dodecyl, n-hexadecyl or n-octadecyl radical, and mixtures thereof.

According to one particularly preferred form of the invention, the monomer of formula (III) comprises at least one alkylene oxide unit (x > 1 ) and preferably several alkylene oxide units (x > 1 ) forming a polyoxyalkylene chain. The polyoxyalkylene chain preferentially is constituted of ethylene oxide units and/or propylene oxide units and more particularly still is constituted of ethylene oxide units (R3=H). The number of oxyalkylene units (or number of moles of alkylene oxide) generally ranges from 3 to 100, more preferentially from 3 to 50 and better still from 7 to 25.

Among these polymers, mention may be made of:

- copolymers, which may or may not be crosslinked and which may or may not be neutralized, comprising from 15% to 60% by weight of 2-acrylamido-2- methylpropanesulfonic acid units and from 40% to 85% by weight of (Cs- Ci6)alkyl(meth)acrylamide units or of (Cs-Ci6)alkyl (meth)acrylate units relative to the polymer, such as those described in document EP-A-750 899;

- terpolymers comprising from 10 mol% to 90 mol% of acrylamide units, from 0.1 ιτιο /ο to 10 ιτιο /ο of 2-acrylamido-2-methylpropanesulfonic acid units and from 5 ιτιο /ο to 80 ιτιο /ο of n-(C6-Ci8)alkylacrylamide units relative to the polymer, such as those described in document US-A-5 089 578;

- non-crosslinked copolymers of partially or totally neutralized 2-acrylamido-2- methylpropanesulfonic acid and of n-dodecyl, n-hexadecyl or n-octadecyl methacrylate;

- crosslinked or non-crosslinked copolymers of partially or totally neutralized 2- acrylamido-2-methylpropanesulfonic acid and of n-dodecylmethacrylamide.

Mention may be made more particularly of copolymers constituted of (i) 2- acrylamido-2-methylpropanesulfonic acid units of formula (II) indicated above, in which X⁺ is a proton, an alkali metal cation, an alkaline-earth metal cation or the ammonium ion, and (ii) units of formula (IV) below:

in which x denotes an integer ranging from 3 to 100, preferably from 3 to 50, and preferentially from 7 to 25; Ri has the same meaning as that indicated above in formula (III) and R₄ denotes a linear or branched alkyl radical comprising from 6 to 22 carbon atoms and preferably from 10 to 22 carbon atoms.

The polymers of this type that are particularly preferred are those for which x = 25, Ri denotes methyl and R₄ represents n-dodecyl; or those for which x = 8 or 25, Ri denotes methyl and R₄ represents n-hexadecyl (Ci6), n-octadecyl (Cis), or n- dodecyl (C12), or mixtures thereof. The polymers for which X⁺ denotes sodium or ammonium are more particularly preferred.

The polymers capable of being used in the composition in accordance with the invention may be obtained according to conventional free-radical polymerization processes in the presence of one or more initiators, for instance azobisisobutyronitrile (AIBN), azobisdimethylvaleronitrile, 2,2-azobis[2- amidinopropane] hydrochloride (ABAH), organic peroxides such as dilauryl peroxide, benzoyl peroxide, tert-butyl hydroperoxide; mineral peroxide compounds such as potassium persulfate or ammonium persulfate, or H2O2 optionally in the presence of reducing agents.

These hydrophobic modified polymers may be obtained especially by free-radical polymerization in a tert-butanol medium, in which they precipitate. By using precipitation polymerization in tert-butanol, it is possible to obtain a size distribution of the polymer particles that is particularly favourable for its uses.

The reaction may be performed at a temperature of between 0 and 150°C and preferably between 10 and 100°C, either at atmospheric pressure or under reduced pressure. It may also be performed under inert atmosphere and preferably under nitrogen.

These preferred hydrophobic modified polymers are in particular those described in document EP 1 069 142, and especially those obtained by polymerization of 2- acrylamido-2-methylpropanesulfonic acid or a sodium or ammonium salt thereof with a (meth)acrylic acid ester and

- of a C10-C18 alcohol oxyethylenated with 8 mol of ethylene oxide (Genapol® C- 080 from Clariant), - of a O oxo alcohol oxyethylenated with 8 mol of ethylene oxide (Genapol® UD- 080 from Clariant),

- of a O oxo alcohol oxyethylenated with 7 mol of ethylene oxide (Genapol® UD- 070 from Clariant),

- of a C12-C14 alcohol oxyethylenated with 7 mol of ethylene oxide (Genapol® LA- 070 from Clariant),

- of a C12-C14 alcohol oxyethylenated with 9 mol of ethylene oxide (Genapol® LA- 090 from Clariant),

- of a C12-C14 alcohol oxyethylenated with 1 1 mol of ethylene oxide (Genapol® LA- 1 10 from Clariant),

- of a C16-C18 alcohol oxyethylenated with 8 mol of ethylene oxide (Genapol® T- 080 from Clariant),

- of a C16-C18 alcohol oxyethylenated with 15 mol of ethylene oxide (Genapol® T- 150 from Clariant),

- of a C16-C18 alcohol oxyethylenated with 1 1 mol of ethylene oxide (Genapol® T- 1 10 from Clariant),

- of a C16-C18 alcohol oxyethylenated with 20 mol of ethylene oxide (Genapol® T- 200 from Clariant),

- of a C16-C18 alcohol oxyethylenated with 25 mol of ethylene oxide (Genapol® T- 250 from Clariant),

- of a C18-C22 alcohol oxyethylenated with 25 mol of ethylene oxide and/or of a C16- C18 iso alcohol oxyethylenated with 25 mol of ethylene oxide.

The molar percentage concentration of units of formula (II) and of units of formula (IV) in the polymers according to the invention varies as a function of the desired cosmetic application and of the rheological properties sought for the formulation. It can range between 0.1 and 99.9 mol%.

Preferably, for the most hydrophobic polymers, the molar proportion of units of formula (II) or (IV) ranges from 50.1 % to 99.9%, more particularly from 70% to 95% and more particularly still from 80% to 90%.

Preferably, for the polymers that are not very hydrophobic, the molar proportion of units of formula (II) or (IV) ranges from 0.1 % to 50%, more particularly from 5% to 25% and more particularly still from 10% to 20%.

The composition according to the invention may comprise the polymer or polymers comprising at least one monomer containing a sulfonic group in an amount ranging from 0.01 % to 10% by weight, preferably from 0.05% to 5% by weight, better still from 0.1 % to 3% by weight and preferentially from 0.2% to 2% by weight, relative to the total weight of the composition.

3/ Other ingredients

The composition according to the invention may be for cosmetic or pharmaceutical use. Preferably, the composition according to the invention is for cosmetic use. "Cosmetic" is understood to mean, within the meaning of the invention, a composition of pleasant appearance, odour and feel. Preferably, the composition is for topical application to the skin and keratin fibres and more especially to the scalp, hair and eyelashes.

The composition according to the invention may be in the form of an aqueous, alcoholic, aqueous-alcoholic or oily solution or suspension, of an emulsion, of liquid or semi-liquid consistency, obtained by dispersing a fatty phase in of an aqueous phase (O/W) or vice versa (W/O), or of an aqueous, alcoholic, aqueous-alcoholic or oily (anhydrous) gel.

Preferably, the composition according to the invention is in the form of an aqueous, alcoholic or aqueous-alcoholic, preferably aqueous-alcoholic, generally thickened, solution or lotion.

The composition according to the invention comprises water in an amount ranging from 20% to 80% by weight, or even from 30% to 50% by weight, relative to the total weight of the composition. Advantageously, the composition according to the invention comprises one or more C2-C₄ monoalcohols such as ethanol and isopropanol, especially in an amount ranging from 10% to 90% by weight, in particular ranging from 20% to 80% by weight, or even from 30% to 70% by weight, better still ranging from 40% to 60% by weight, relative to the total weight of the composition.

The composition according to the invention may also comprise one or more additional organic solvents, other than C2-C₄ monoalcohols, for example selected from polyols, especially those containing from 2 to 6 carbon atoms, for instance glycerol, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, dipropylene glycol or diethylene glycol; and polyol ethers such as 2-butoxyethanol, propylene glycol monomethyl ether, and diethylene glycol monoethyl ether and monomethyl ether; and mixtures thereof.

The composition according to the invention may also comprise one or more addi- tional thickeners, other than polymers comprising at least one monomer containing a sulfonic group above, in particular selected from carboxyvinyl polymers (car- bomers), acrylic copolymers, such as acrylate/alkyl acrylate copolymers, poly- acrylamides, polysaccharides, such as hydroxypropyl cellulose, natural gums and clays, and mention may be made, as lipophilic gelling agents, of modified clays, such as bentones, metal salts of fatty acids, such as aluminium stearates, hydrophobic treated silica, ethyl cellulose and mixtures thereof.

The composition according to the invention may also comprise one or more stand- ard cosmetic additives, in particular selected from nonionic, anionic, cationic and amphoteric surfactants, vitamins, sunscreens, fillers, colourants, nacreous agents, opacifiers, film-forming polymers, conditioners, liquid or solid fatty substances, antioxidants, fragrances and preservatives.

In one advantageous embodiment of the invention, the composition may also comprise one or more fixing polymers selected from nonionic, anionic, cationic or amphoteric fixing polymers, preferably from anionic or cationic fixing polymers. In one particular embodiment, the composition according to the invention may comprise at least one vitamin B and/or an analogue or derivative thereof. Preferably, the vitamin B capable of being employed in the context of the invention is chosen from vitamin B3, vitamin B5, vitamin B6 and vitamin B8 or an analogue or derivative thereof, and in particular calcium pantothenate, panthenol, panthenyl ethyl ether, panthenyl ethyl ether acetate and panthenyl triacetate, and also mixtures thereof.

In this embodiment, the composition according to the invention preferably comprises the vitamin or vitamins B, analogue(s) and/or derivative(s) in an amount of between 0.001 % and 5% by weight, in particular 0.005% and 2% by weight and better still between 0.01 % and 1 % by weight, relative to the total weight of the composition.

In one particular embodiment, the composition may comprise active agents that favour the regrowth of human keratin fibres and/or that limit the loss thereof, other than the pyridinedicarboxylic acid esters according to the invention, and which may be selected from aminexil, 6-O-[(9Z,12Z)-octadeca-9,12- dienoyl]hexapyranose, pyrimidine derivatives, such as 2,4-diamino-6- piperidinopyrimidine 3-oxide; antiseborrheic agents and/or antidandruff agents such as octopirox or zinc pyrithione.

Advantageously, the composition according to the invention is a hair composition, capable of being applied to the scalp and/or the hair, and may be in the form of a hair care lotion, for example for daily or twice-weekly application, of a shampoo or of a hair conditioner, in particular for twice-weekly or weekly application, of a liquid or solid soap for cleaning the scalp for daily application, of a treatment mask, of a cream or of a foaming gel for cleaning the hair. It may also be in the form of a hair dye or mascara to be applied with a brush or comb.

The composition according to the invention, in particular the cosmetic composition, may be applied to the alopecic areas of the scalp and/or to the hair, optionally left in contact for several hours and/or optionally rinsed out.

It is possible, for example, to apply the composition according to the invention in the evening, to keep the latter in contact overnight and optionally to shampoo in the morning. These applications can be repeated daily for one or more months, according to the individuals.

Another subject of the present invention is a method for the cosmetic treatment of human keratin materials, in particular hair and/or skin, including the scalp, in which a cosmetic composition as defined above is applied to said keratin materials, it being possible for said application to optionally be followed by a step of rinsing said keratin materials.

More especially, said method is a method for the cosmetic treatment, in particular for the care, of the hair and/or scalp, for the purpose of improving their condition and/or their appearance. This treatment method indeed exhibits the characteristics of a cosmetic method in so far as it makes it possible to improve the attractiveness of keratin materials, in particular hair, by giving them greater vigour, an improved appearance (provision of conditioning) and greater ease of handling (spreading, distribution) and of styling.

The invention is described in more detail in the following examples.

Example 1

The following composition is prepared (% by weight, AM active material):

- diethyl ester of 2,4-pyridinedicarboxylic acid

(INCI name: Diethyl lutidinate) 5%

- Ammonium polyacryloyldimethyl taurate (INCI name)

Hostacerin AMPS from Clariant 0.5% AM

- ethanol 56.5%

- water q.s. for 100%

This gelled lotion is clear and stable over time (at least 2 months, at 25°C or 45°C). Applied line by line to the scalp, this lotion exhibits good qualities of use, promoting the delivery and the distribution of the active principles over the scalp.

It also exhibits a good cosmetic performance. The hair is silky and light and the head of hair is well-behaved and easy to style.

Example 2

The following composition is prepared (% by weight, AM = active material):

- diethyl ester of 2,4-pyridinedicarboxylic acid

(INCI name: Diethyl lutidinate) 5%

- Ammonium polyacryloyldimethyl taurate (INCI name)

Hostacerin AMPS from Clariant 0.75% AM

- Ethyl ester of PVM/MA copolymer 0.5%

- ethanol 56.5%

- water q.s. for 100%

This gelled lotion is clear and stable over time (at least 2 months, at 25°C or 45°C). Applied line by line to the scalp, this lotion exhibits good qualities of use, promoting the delivery and the distribution of the active principles over the scalp. It also exhibits a good cosmetic performance. It provides hold, body and volume to the head of hair.

Claims

1 . Composition comprising:

- (i) at least one compound of general formula (I), or a salt thereof:

in which Ri and R2 represent, independently of one another, a hydrogen atom, a saturated or unsaturated, linear or branched C1-C18 aliphatic hydrocarbon radical; or a C6-C18 aryl radical; said radicals optionally being substituted by one or more groups selected from OH, NH₂, -OR, -OCOR and -NHR with R representing a Ci- C18 alkyl group; at least one of the Ri and R2 groups being other than a hydrogen atom; and

2. Composition according to Claim 1 , in which Ri and R2 represent, independently of one another, a hydrogen atom or a saturated, linear or branched, aliphatic Ci- C18, better still C1-C10, indeed even C1-C6, hydrocarbon radical, in particular alkyl radical, which is optionally substituted by an alkoxy or acyloxy group (OR or OCOR with R denoting a C1-C18 alkyl radical), at least one of the R1 and R2 groups being other than a hydrogen atom.

3. Composition according to either of the preceding claims, in which Ri and R2 are identical and represent a saturated linear C1-C18, preferably C1-C10 and better still C1-C6 alkyl radical and very particularly an ethyl radical.

4. Composition according to one of the preceding claims, comprising, as compound of formula (I), one of the following compounds:

- dimethyl 2,4-pyridinedicarboxylate,

- dimethyl 2,3-pyridinedicarboxylate,

- diethyl 2,4-pyridinedicarboxylate,

- diethyl 2,3-pyridinedicarboxylate,

- diethyl 2,5-pyridinedicarboxylate,

- dimethyl 2,5-pyridinedicarboxylate,

- diisopropyl 2,4-pyridinedicarboxylate, - di(acetyloxymethyl) 2,4-pyridinedicarboxylate.

5. Connposition according to one of the preceding claims, comprising the compound^) of formula (I) in an amount greater than or equal to 0.5% by weight, in particular between 0.5% and 20% by weight, in particular ranging from 3% to 15% by weight and better still ranging from 4% to 10% by weight, relative to the total weight of the composition.

6. Composition according to one of the preceding claims, in which the polymer or polymers comprising at least one monomer containing a sulfonic group comprise at least one monomer selected from vinylsulfonic acid, styrenesulfonic acid, (meth)acrylamido(Ci-C22)alkylsulfonic acids, N-(Ci-C22)alkyl(meth)acrylamido(Ci- C22)alkylsulfonic acids such as undecylacrylamidomethanesulfonic acid, and also the partially or totally neutralized forms thereof, and the mixtures thereof; prefera- bly selected from (meth)acrylamido(Ci-C22)alkylsulfonic acids such as for example acrylamidomethanesulfonic acid, acrylamidoethanesulfonic acid, acrylamidopro- panesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methacrylamido- 2-methylpropanesulfonic acid, 2-acrylamido-n-butanesulfonic acid, 2-acrylamido- 2,4,4-trimethylpentanesulfonic acid, 2-methacrylamidododecylsulfonic acid, 2- acrylamido-2,6-dimethyl-3-heptanesulfonic acid, and also the partially or totally neutralized forms thereof, and the mixtures thereof; and very particularly a monomer of 2-acrylamido-2-methylpropanesulfonic acid type, and also the partially or totally neutralized forms thereof.

7. Composition according to one of the preceding claims, in which the polymer or polymers comprising at least one monomer containing a sulfonic group are crosslinked and/or are homopolymers.

8. Composition according to one of the preceding claims, comprising at least one 2-acrylamido-2-methylpropanesulfonic acid homopolymer comprising, randomly distributed:

a) from 90% to 99.9% by weight of units of general formula (II) below:

CH,

in which X⁺ denotes a proton, an alkali metal cation, an alkaline-earth metal cation or the ammonium ion, not more than 10 mol% of the cations X⁺ possibly being protons H⁺; and

b) from 0.01 % to 10% by weight of crosslinking units originating from at least one monomer containing at least two olefinic double bonds; the weight proportions being defined relative to the total weight of the polymer.

9. Composition according to one of Claims 1 to 6, comprising at least one copolymer that can be obtained from ethylenically unsaturated monomers containing a sulfonic group and ethylenically unsaturated hydrophilic monomers, in particular selected from:

- (1 ) crosslinked anionic copolymers of acrylamide or methacrylamide and of 2- acrylamido-2-methylpropanesulfonic acid,

- (2) copolymers of (meth)acrylic acid or of (meth)acrylate and of 2-acrylamido-2- methylpropanesulfonic acid,

- (3) copolymers of 2-acrylamido-2-methylpropanesulfonic acid and of vinylpyrrolidone or vinylformamide.

10. Composition according to one of Claims 1 to 6, comprising at least one copolymer that can be obtained from ethylenically unsaturated monomers containing a sulfonic group and ethylenically unsaturated hydrophobic monomers, that is to say comprising a C6-C50 fatty chain, in particular selected from:

- copolymers, which may or may not be crosslinked and which may or may not be neutralized, comprising from 15% to 60% by weight of 2-acrylamido-2- methylpropanesulfonic acid units and from 40% to 85% by weight of (Cs- Ci6)alkyl(meth)acrylamide units or of (Cs-Ci6)alkyl (meth)acrylate units, relative to the polymer,

- terpolymers comprising from 10 mol% to 90 mol% of acrylamide units, from 0.1 ιτιο /ο to 10 ιτιο /ο of 2-acrylamido-2-methylpropanesulfonic acid units and from

5 ιτιο /ο to 80 ιτιο /ο of n-(C6-Ci8)alkylacrylamide units, relative to the polymer,

1 1 . Composition according to one of the preceding claims, comprising the polymer or polymers comprising at least one monomer containing a sulfonic group in an amount ranging from 0.01 % to 10% by weight, preferably from 0.05% to 5% by weight, better still from 0.1 % to 3% by weight and preferentially from 0.2% to 2% by weight, relative to the total weight of the composition.

12. Composition according to one of the preceding claims, comprising one or more C2-C₄ monoalcohols such as ethanol and isopropanol, especially in an amount ranging from 10% to 90% by weight, in particular ranging from 20% to 80% by weight, or even from 30% to 70% by weight, better still ranging from 40% to 60% by weight, relative to the total weight of the composition.

13. Composition according to one of the preceding claims, comprising:

- one or more additional organic solvents, for example selected from polyols, especially those containing from 2 to 6 carbon atoms, for instance glycerol, propyl- ene glycol, butylene glycol, pentylene glycol, hexylene glycol, dipropylene glycol or diethylene glycol; and polyol ethers such as 2-butoxyethanol, propylene glycol monomethyl ether, and diethylene glycol monoethyl ether and monomethyl ether; and mixtures thereof; and/or

- one or more additional thickeners, in particular selected from carboxyvinyl poly- mers (carbomers), acrylic copolymers, such as acrylate/alkyl acrylate copolymers, polyacrylamides, polysaccharides, such as hydroxypropyl cellulose, natural gums and clays, and mention may be made, as lipophilic gelling agents, of modified clays, such as bentones, metal salts of fatty acids, such as aluminium stearates, hydrophobic treated silica, ethyl cellulose and mixtures thereof, and/or

- one or more fixing polymers, and/or

- at least one vitamin B and/or an analogue or derivative thereof, selected in particular from vitamin B3, vitamin B5, vitamin B6 and vitamin B8 or an analogue or derivative thereof, and in particular calcium pantothenate, panthenol, panthenyl ethyl ether, panthenyl ethyl ether acetate and panthenyl triacetate, and also mix- tures thereof; and/or

- active agents that favour the regrowth of human keratin fibres and/or that limit the loss thereof such as aminexil, 6-O-[(9Z,12Z)-octadeca-9,12-dienoyl]hexapyranose, pyrimidine derivatives, such as 2,4-diamino-6-piperidinopyrimidine 3-oxide; anti- seborrheic agents and/or antidandruff agents such as octopirox or zinc pyrithione.

14. Method for the cosmetic treatment of keratin materials, in particular the hair and/or the skin, including the scalp, in which a cosmetic composition as defined in one of the preceding claims is applied to said keratin materials and said keratin materials are optionally rinsed.