Gelling composition comprising short chain fatty acid salts

Abstract

The present invention relates to a composition, in particular a cosmetic composition, in particular for the care of keratin materials, in particular the skin, comprising from 0.5% to 4% by weight of a short-chain fatty acid salt relative to the total weight of the composition and at least 90% by weight of an aqueous phase, the aqueous phase being gelled by a hydrophilic gelling agent selected from (i) at least one polymer selected from polyacrylamide and 2-acrylamido-2-methylpropanesulfonic acid polymers and copolymers, (ii) at least one polysaccharide produced by a microorganism or isolated from algae, (iii) at least one of cellulose or its derivatives, (iv) at least one carboxyvinyl polymer, or (v) one of their mixtures. The present invention also relates to a cosmetic method for the care of keratin materials, in particular the skin, comprising at least one stage of applying the composition of the present invention to the keratin material.

Description

[0001] The present invention relates to the field of cosmetology, in particular to a cosmetic use for preventing and / or caring for keratin materials, in particular dry skin and / or aged skin, such as hyposeborrheic dry skin and / or aged skin. Technical Field

[0002] Starting from the age of 60 or 65, the skin becomes less supple, especially due to a decrease in sebum production.

[0003] It is known practice to incorporate active agents in cosmetic and / or dermatological compositions in order to combat the signs of aging.

[0004] The skin is a complex tissue matrix that mediates a wide range of functions in the human body. To this end, the skin has specialized cells and mechanisms, many of which are unique to this organ.

[0005] Human skin consists of two layers, the upper layer, the epidermis, and the deeper layer, the dermis. The natural human epidermis is mainly composed of four types of cells, namely: keratinocytes (the vast majority), melanocytes, sebaceous gland cells and Langerhans cells.

[0006] Each of these cell types contributes to the important role that the skin plays in the body by virtue of its inherent functions. In particular, sebocytes, which are found in the sebaceous glands of the skin, are cells that synthesize an oily substance called sebum.

[0007] Sebum is a product secreted by the sebaceous glands of the skin of most mammals. The secretory mechanism is a full secretory mechanism in which sebum is deposited on the surface of the skin. One of the functions of sebum is to provide a hydrophobic coating to the skin through the sebaceous gland ducts. In addition, human sebum has unique properties compared to other mammals. In particular, it contains very small amounts of cholesterol derivatives and a large amount of squalene. In particular, sebum is a mixture of triglycerides, wax esters, squalene, cholesterol esters, cholesterol and free fatty acids.

[0008] The importance of sebum in the homeostasis of skin tissue is known: parts of the human body lacking sebum (sole and palms) reveal a morphology and aesthetics of the skin surface that are completely different from the morphology and aesthetics of other parts of the skin. Similarly, in the field of skin care, certain aesthetic conditions (dry skin) and major skin conditions (premature aging) seem to be due to the lack or deficiency of sebum at the skin surface. Hyposeborrheic dry skin or an example of skin becoming such is observed during skin aging. Therefore, the manifestation of dry diseases associated with sebum deficiency is very common in the elderly, and especially in individuals over 50 years old (Yamamoto, A., Serizawa, S., Ito, M. and Sato, Y., Effect of aging on sebaceous gland activity and on the fatty acid composition of wax esters, J. Invest. Dermatol., 89, 507–512 (1987)). Background Art

[0009] In order to overcome this problem and provide comfortable care products that have a stimulating effect on sebum production, various technical solutions are currently provided on the cosmetics market.

[0010] In addition, in a patent application numbered 10201811547R filed in Singapore on December 21, 2018, it is proposed to use short-chain fatty acids (SCFAs) containing 3 to 8 carbon atoms, in particular propionate, butyrate and valerate, to increase the synthesis of sebum lipids and also the secretion of sebum, thereby preventing and / or treating dry skin and / or aging skin, in particular dry skin and / or aging skin associated with a lack of sebum secretion.

[0011] Thus, it is already known from US20090022819 that lysates of the filamentous bacterium Vitreoscilla filiformis can be used for preventing and / or treating dry skin.

[0012] Furthermore, US20090060962 describes the use of bifidobacterium lysates for preventing and / or treating dry skin.

[0013] However, in these applications, the active agent is composed of bacterial biomass. One of the drawbacks of using such biomass is that its incorporation into cosmetic compositions can lead to stability problems and, in particular, phase separation caused by biomass sedimentation.

[0014] In the prior art, no short-chain fatty acid (SCFA) is used as an active ingredient for preventing and / or treating dry skin and / or aging skin. In particular, propionic acid is known from CTFA (Personal Care Products Council) and Shu, M. et al. [Fermentation of Propionibacterium acnes, a common bacterium in the human skin microbiome, as skin probiotics against methicillin-resistant Staphylococcus aureus. PloS One 8, e55380 (2013)] as an antimicrobial active agent, and its salt (propionate) as a pH corrector and has never been described as acting on lipid production and sebum secretion.

[0015] In addition, among the short-chain fatty acids (SCFA) known in cosmetics, acetate (a short-chain fatty acid containing 2 carbon atoms) is described as a lipid production inducer (Acne and Its Therapy, Guy F. Webster and Anthony V. Rawlings, page 262). However, acetate only contributes to lipid production, not sebum secretion. Both lipid production and sebum secretion are required for the effective treatment of hyposeborrheic skin.

[0016] However, the salified forms of these short chain fatty acids (e.g. sodium propionate) are water soluble, making their dosage formulation tricky. In particular, in the case of sodium propionate, due to its pKa of 4.8, its salified form in cosmetic compositions, which typically have a pH of 6 to 7, makes its dosage formulation tricky, especially in terms of compatibility with gelling agents traditionally used in the cosmetic industry.

[0017] Furthermore, it is important to maintain a pH between 6 and 7 in order to limit the risk of developing sour tastes due to propionic acid (which are more pronounced at pH values ​​below 5.5). Summary of the invention

[0018] There is therefore still a need for useable cosmetic solutions capable of stimulating the production of sebum in aged skin, in particular skin older than 60 years, indeed even older than 65 years, and more particularly cosmetic compositions comprising at least one salt of a short-chain fatty acid, in particular sodium propionate, in a dosage form suitable for its application to the skin while observing the pH usually used in the cosmetic industry, i.e. around 6 to 7.

[0019] The present invention is specifically directed to meeting this need. SUMMARY OF THE INVENTION

[0021] Thus, according to one of its aspects, the invention relates to a composition, in particular a cosmetic composition, in particular for the care of keratin materials, in particular the skin, comprising:

[0022] - 0.5% to 4% by weight, relative to the total weight of the composition, of short-chain fatty acid salts comprising a saturated or unsaturated and linear or branched aliphatic chain containing from 3 to 8 carbon atoms, preferably from 3 to 5 carbon atoms, and

[0023] at least 90% by weight of an aqueous phase, relative to the total weight of the composition, gelled by a hydrophilic gelling agent chosen from:

[0024] (i) at least one polymer selected from the group consisting of polyacrylamide and 2-acrylamido-2-methylpropanesulfonic acid polymers and copolymers,

[0025] (ii) at least one polysaccharide produced by a microorganism or isolated from algae,

[0026] (iii) at least one of cellulose or a derivative thereof,

[0027] (iv) at least one carboxyvinyl polymer, or

[0028] (v) a mixture thereof.

[0029] The inventors have surprisingly found that short chain fatty acid salts, in particular sodium propionate, can advantageously be formulated in a gelling composition comprising at least 90 wt % of an aqueous phase relative to the total weight of the composition, provided that it is gelled by a gelling agent selected from the above mentioned.

[0030] The inventors have particularly observed that although it is known that C 16 -C 30 Alkyl chain hydrophobically modified acrylic acid polymers have a favorable compatibility with salts, but this property is not verified in the presence of short chain fatty acid salts, especially in the presence of sodium propionate, as reported in the experimental section below.

[0031] The inventors have surprisingly found that the composition according to the invention can effectively stabilize short-chain fatty acid salts, in particular sodium propionate, in an amount that can vary from 0.5% to 4% by weight relative to the total weight of the composition, in particular it can vary from 1% to 3% by weight, optionally in combination with other active agents.

[0032] This is because (as can be seen from the examples that appear below) the compositions according to the invention are stable, in particular from a rheological point of view.

[0033] The compositions according to the invention are particularly useful for caring for the skin.

[0034] According to another of its aspects, the invention therefore also relates to a cosmetic method for caring for keratin materials, in particular the skin, comprising at least one stage of applying to the skin a composition according to the invention.

[0035] The invention also relates to a cosmetic treatment method for preventing and / or treating dry skin and / or aged skin, in particular hyposeborrheic dry skin and / or aged skin, comprising at least one stage of applying to the skin a composition according to the invention.

[0036] Other characteristics, alternative forms and advantages of the composition according to the invention will emerge more clearly on reading the description and the accompanying examples.

[0037] The term "keratin material" is particularly understood to mean the skin, the lips, in particular the skin and / or the lips, and preferably the skin.

[0038] In the context of the present invention, the term "skin" refers to any skin surface of the body, preferably the facial skin and the scalp. It is expected that the skin to which this patent application relates is human skin.

[0039] As used herein, the term "to treat" or "treatment" refers to any action intended to improve the comfort or well-being of an individual. Thus, the term encompasses the reduction, alleviation or elimination of symptoms of dry skin and / or aging skin, but only in the case of cosmetic treatments.

[0040] Within the meaning of the present invention, the term "preventing" means, in particular in the context of the present invention, reducing the risk of occurrence of the phenomena of dry skin and / or aged skin.

[0041] The term "hyposeborrheic" is understood to mean an absence of sebum secretion, in particular an absence or reduction of sebum secretion of the sebaceous glands. Typically, less than 100 μg / cm2 measured in the T-zone of the face by the method described in FR 2 368 708. 2 A sebum content of 1% can be considered a characteristic of hyposeborrheic dry skin and aging skin.

[0042] Within the meaning of the present invention, the term "cosmetic composition" denotes a composition suitable for application to the skin, in particular a composition comprising a physiologically acceptable medium.

[0043] The term "physiologically acceptable medium" means a medium suitable for topical application of the composition, that is, a medium that is compatible (non-toxic) with the skin of the face, body and scalp.

[0044] For the purposes of the present invention, the term "short-chain fatty acids" means carboxylic acids having an aliphatic chain containing from 3 to 8 carbon atoms, preferably carboxylic acids having an aliphatic chain containing from 3 to 5 carbon atoms. DETAILED DESCRIPTION

[0045] Salts of short-chain fatty acids (SCFA) containing 3 to 8 carbon atoms

[0046] More particularly, the short-chain fatty acids according to the invention comprise a saturated or unsaturated and linear or branched aliphatic chain containing from 3 to 8 carbon atoms, preferably from 3 to 5 carbon atoms.

[0047] According to one embodiment of the present invention, the short-chain fatty acids comprise saturated and linear aliphatic chains containing 3 to 5 carbon atoms.

[0048] According to an even more specific embodiment, the short-chain fatty acids are chosen from propionic acid, butyric acid, valeric acid and mixtures thereof.

[0049] Advantageously, the short-chain fatty acids according to the invention do not contain hydroxylated aliphatic chains; preferably, the short-chain fatty acids are not alpha-hydroxy acids and beta-hydroxy acids, in particular are not lactic acid.

[0050] The short-chain fatty acid salt according to the invention may be any salt suitable for cosmetic use. Calcium, sodium, magnesium and potassium salts may be mentioned in particular, with sodium salt being most particularly preferred.

[0051] Amino acid salts may also be used. For example, carnitine salts or lysine salts of short chain fatty acids according to the invention may be used. Those skilled in the art will be able to identify various other amino acids that may also be used in the context of the present invention.

[0052] Therefore, according to a specific embodiment of the present invention, the short-chain fatty acid salt is selected from one of propionate, butyrate, valerate or a mixture thereof, and the salt can be selected from calcium salt, sodium salt, magnesium salt and potassium salt, and more particularly sodium salt, especially sodium propionate.

[0053] According to a specific embodiment, the short-chain fatty acids are obtained from at least one microorganism of the species Propionibacterium acnes, preferably from at least one microorganism of the Propionibacterium acnes ATCC 6919 strain.

[0054] In another embodiment, the short-chain fatty acids according to the present invention are contained in the conditioned medium (or supernatant) of at least one microorganism of the species Propionibacterium acnes, preferably in the conditioned medium of at least one microorganism of the strain Propionibacterium acnes ATCC6919.

[0055] As examples of short-chain fatty acid salts suitable for the present invention, mention may be made of sodium propionate (Ref. P1880) and sodium butyrate (Ref. 303410) sold by Sigma or sodium propionate obtainable under the trade name Sodium Propionate from Dr. Paul Lohmann.

[0056] "Culture supernatant", also called "conditioned medium", is generally obtained by culturing the microorganisms involved in a medium suitable for the survival and / or growth of the microorganisms, and then by separating the medium and the microorganisms to obtain a medium in contact with the microorganisms. Preferably, the cultivation is carried out for a period of time and under conditions that enable the microorganisms to release the active agent with the desired lipophilic properties, in particular the short-chain fatty acids (SCFA) according to the present invention, into the medium.

[0057] An environment suitable for the survival and / or growth of microorganisms can be composed of any nutrient medium suitable for the survival and / or cultivation of microorganisms. It usually contains an appropriate amount of carbon source and nitrogen source, such as amino acids, sugars, proteins, fatty acids, phosphates, sulfates, minerals and growth factors and vitamins.

[0058] For the purposes of this patent application, the terms "conditioned medium" or "culture supernatant" are used indiscriminately to denote the entire culture supernatant obtained after cultivation of the microorganism in question, or any fraction or by-product of the supernatant obtained by dialysis, fractionation, phase separation, filter chromatography, affinity chromatography, precipitation, concentration, lyophilization, etc.

[0059] In the context of the present invention, the conditioned medium of at least one microorganism of the species Propionibacterium acnes according to the invention can be obtained by a process comprising the following stages:

[0060] i) at least one microorganism of the culture species Propionibacterium acnes, such as Propionibacterium acnes ATCC6919;

[0061] ii) separating the culture supernatant from the biomass, in particular by centrifugation;

[0062] iii) recovering the culture supernatant; and

[0063] iv) optionally stabilizing the culture supernatant, for example by filtration.

[0064] In the context of the present invention, the term "biomass" refers to the P. acnes cells obtained after carrying out stage i).

[0065] Preferably, filtration is performed using a syringe filter with a pore size of 0.45 μm.

[0066] Sodium Propionate

[0067] According to a specific embodiment, the short chain fatty acid salt is sodium propionate.

[0068] Sodium propionate has the following chemical structure:

[0069] [Chemical formula 1]

[0070]

[0071] It is sometimes used as a food additive, especially as a preservative, numbered E281.

[0072] It is water soluble.

[0073] Cosmetic composition

[0074] The composition according to the invention comprises from 0.5% to 4% by weight of short-chain fatty acid salts, particularly from 1% to 3% by weight and more particularly from 1.5% to 2.5% by weight relative to the total weight of the composition.

[0075] Thus, in particular, the composition according to the invention comprises from 0.5% to 4% by weight of sodium propionate, particularly from 1% to 3% by weight and more particularly still from 1.5% to 2.5% by weight relative to the total weight of the composition.

[0076] In a preferred embodiment, the composition according to the invention comprises from 0.8% to 4% by weight of short-chain fatty acids relative to the total weight of the composition, in particular from 0.8% to 3% by weight, more particularly still from 0.8% to 2.5% by weight.

[0077] Preferably, the composition according to the invention comprises from 0.8% to 4% by weight of sodium propionate, particularly from 0.8% to 3% by weight and even more particularly from 0.8% to 2.5% by weight relative to the total weight of the composition.

[0078] According to a particular embodiment, the composition according to the invention comprises 2% of a short-chain fatty acid salt, in particular sodium propionate.

[0079] According to another particular embodiment, the composition according to the invention comprises 0.8% of a short-chain fatty acid salt, in particular sodium propionate.

[0080] The compositions according to the invention are generally suitable for topical application to keratin materials and in particular to the skin and therefore generally comprise a physiologically acceptable medium.

[0081] It is preferably a cosmetically acceptable medium, ie one that exhibits a pleasant colour, odour and feel and does not cause any unacceptable discomfort, ie stinging, tightness or redness, liable to deter the user from applying the composition.

[0082] As indicated above, the present cosmetic composition comprises at least 90% by weight of aqueous phase relative to the total weight of the composition.

[0083] According to a particular embodiment, the pH of the cosmetic composition according to the invention is between 5.8 and 7.2, in particular between 6 and 7.

[0084] As indicated above, maintaining within such a pH range presents in particular the advantage of limiting the risk of forming sour tastes (which can be emitted if propionic acid is formed, in particular for a pH of less than 5.5).

[0085] In order to maintain the pH within this value range, the composition according to the invention may comprise a pH regulator (acid or base). Any pH regulator generally suitable for cosmetic applications may be used in the context of this patent application. Typically, citric acid, lactic acid, tartaric acid, oxalic acid, sodium hydroxide, HEPES, sodium citrate, potassium hydroxide and triethanolamine may be mentioned.

[0086] When the composition contains such a pH adjuster, the acid or base content is adjusted by a person skilled in the art to preferably adjust the pH to 6 to 7.

[0087] The pH value may also be adjusted using the various pH adjusting agents mentioned above, depending on the gelling agent present in the composition according to the invention.

[0088] The composition according to the invention may be provided in the form of a hydrogel. According to this embodiment, the composition is then free of a fatty phase.

[0089] Such hydrogels advantageously exhibit a smooth appearance.

[0090] Furthermore, such hydrogels can be more or less transparent.

[0091] Finally, according to a specific embodiment, this hydrogel provides the properties of softness and velvety feel when applied. This property is reported in the examples by the description of a "creamy" gel.

[0092] According to a particular embodiment, the composition according to the invention may also be provided in the form of a serum. In the context of the present invention, "serum" is understood to mean a composition exhibiting a fluid, flowing and slightly gel texture.

[0093] According to another particular embodiment, the composition according to the invention may contain up to 10% by weight of a fatty phase, as described in more detail below. In this case, in the context of the present invention, such a composition may be described as an "emulsified gel".

[0094] According to a particular embodiment, the composition according to the invention is provided in the form of a hydrogel, a serum or an emulsified gel.

[0095] The cosmetic composition according to the invention may generally exhibit a viscosity ranging from 5 poise (0.5 Pa.s) to 70 poise (7 Pa.s).

[0096] The composition according to the present invention can be prepared according to techniques well known to those skilled in the art.

[0097] Gelling Agent

[0098] As indicated above, the composition according to the invention comprises an aqueous phase gelled by:

[0099] (i) at least one polymer selected from the group consisting of polyacrylamide and 2-acrylamido-2-methylpropanesulfonic acid polymers and copolymers,

[0100] (ii) at least one polysaccharide produced by a microorganism or isolated from algae,

[0101] (iii) at least one of cellulose or a derivative thereof,

[0102] (iv) at least one carboxyvinyl polymer, or

[0103] (v) a mixture thereof.

[0104] The gelling agents employed in the context of the present invention are gelling agents for the aqueous phase. They can therefore be more particularly described as hydrophilic gelling agents.

[0105] Within the meaning of the present invention, "hydrophilic gelling agent" is understood to mean a compound capable of gelling the aqueous phase of the composition according to the invention.

[0106] The gelling agent is hydrophilic in nature and is therefore present in the aqueous phase of the composition.

[0107] The gelling agent may be water soluble or water dispersible.

[0108] According to a particular embodiment, the aqueous phase of the composition according to the invention is gelled with 0.1% to 8% by weight of at least one hydrophilic gelling agent relative to the total weight of the aqueous phase.

[0109] Preferably, the aqueous phase of the composition according to the invention is gelled with 0.5% to 8% by weight, more particularly still 0.8% to 4% by weight, in particular for example 0.8% to 3% by weight, of at least one hydrophilic gelling agent relative to the total weight of the aqueous phase.

[0110] According to a specific embodiment, the hydrophilic gelling agent may be selected from (i) polymers selected from polyacrylamide and 2-acrylamido-2-methylpropanesulfonic acid polymers and copolymers.

[0111] Polyacrylamide and 2-acrylamido-2-methylpropanesulfonic acid polymers and copolymers

[0112] The polymer suitable for use as the hydrogelling agent of the present invention may be a polymer containing at least 2-acrylamido-2-methylpropanesulfonic acid. A crosslinked or non-crosslinked homopolymer or copolymer of a monomer in a form partially or completely neutralized with an inorganic base other than ammonia (e.g. sodium hydroxide or potassium hydroxide).

[0113] (monomer) is a registered trademark of Lubrizol.

[0114] They are preferably completely or almost completely neutralized, that is to say at least 90% neutralized.

[0115] According to these The polymers may be cross-linked or non-cross-linked.

[0116] When the polymer is crosslinked, the crosslinking agent may be chosen from polyolefin unsaturated compounds commonly used for crosslinking polymers obtained by free-radical polymerization.

[0117] For example, crosslinkers which may be mentioned are divinylbenzene, diallyl ether, dipropylene glycol diallyl ether, polyethylene glycol diallyl ether, 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, allyl ethers of alcohols of the sugar series or other allyl or vinyl ethers of multifunctional alcohols, and also allyl esters of phosphoric acid and / or vinylphosphonic acid derivatives, or mixtures of these compounds.

[0118] According to a preferred embodiment of the present invention, the crosslinking agent is selected from methylenebisacrylamide, allyl methacrylate or trimethylolpropane triacrylate (TMPTA). For polymers, the degree of crosslinking generally ranges from 0.01 mol% to 10 mol%, and more particularly from 0.2 mol% to 2 mol%.

[0119] Suitable for the present invention The polymers are either water soluble or water dispersible. In this case, they either consist only of A "homopolymer" of a monomer and (if they are cross-linked) one or more cross-linking agents (such as those defined above) is either and copolymers obtained from one or more hydrophilic or hydrophobic ethylenically unsaturated monomers and, if they are crosslinked, one or more crosslinking agents, such as those defined above. When the copolymer comprises hydrophobic ethylenically unsaturated monomers, the latter do not comprise fatty chains and are preferably present in small amounts.

[0120] Within the meaning of the present invention, the term "fatty chain" is understood to mean any hydrocarbon chain comprising at least 7 carbon atoms.

[0121] The term "water-soluble or water-dispersible" is understood to mean a polymer that is capable of obtaining a macroscopically homogeneous and transparent solution (i.e. a solution having a maximum transmittance value of at least 60% and preferably at least 70% through a sample 1 cm thick at a wavelength equal to 500 nm) when introduced into an aqueous phase at a concentration by weight equal to 1% at 25°C.

[0122] The "homopolymers" according to the invention are preferably crosslinked and neutralized and they are obtainable according to a preparation process comprising the following stages: (a) monomers (e.g. ) is dispersed or dissolved in free form in tert-butanol or in a solution of water and tert-butanol; (b) the monomer solution or dispersion obtained in (a) is neutralized with one or more inorganic or organic bases (preferably ammonia NH3) in an amount that can obtain a degree of neutralization of the sulfonic acid functional groups of the polymer ranging from 90% to 100%; (c) one or more crosslinking monomers are added to the solution or dispersion obtained in (b); (d) conventional free radical polymerization is carried out in the presence of a free radical initiator at a temperature ranging from 10°C to 150°C, and the polymer is precipitated from the tert-butanol-based solution or dispersion.

[0123] The water-soluble or water-dispersible The copolymer contains water-soluble ethylenically unsaturated, hydrophobic monomers or mixtures thereof.

[0124] The water-soluble comonomers may be ionic or nonionic.

[0125] For example, among the ionic water-soluble comonomers, the following compounds and their salts may be mentioned: (meth)acrylic acid, styrenesulfonic acid, vinylsulfonic acid and (meth)allylsulfonic acid, vinylphosphonic acid, maleic acid, itaconic acid, crotonic acid, water-soluble vinyl monomers of the following formula (A):

[0126] [Chemical formula 2]

[0127]

[0128] wherein R1 is selected from H, -CH3, -C2H5 or -C3H7; X1 is selected from an alkyl oxide of the -OR2 type, wherein R2 is a saturated or unsaturated, linear or branched hydrocarbon group having 1 to 6 carbon atoms, supported by at least one sulfonic acid group (-SO3 - ) and / or sulfate (-SO4 - ) and / or phosphate (-PO4H2) groups.

[0129] Among the nonionic water-soluble comonomers, mention may be made of, for example, (meth)acrylamide, N-vinylacetamide and N-methyl-N-vinylacetamide, N-vinylformamide and N-methyl-N-vinylformamide, maleic anhydride, vinylamide, N-vinyllactams (containing cyclic alkyl groups having 4 to 9 carbon atoms), for example N-vinylpyrrolidone, N-butyrolactam and N-vinylcaprolactam, vinyl alcohols of the formula CH2=CHOH, water-soluble vinyl monomers of the following formula (B):

[0130] [Chemical formula 3]

[0131]

[0132] Wherein R3 is selected from H, -CH3, -C2H5 or -C3H7; X2 is selected from an alkyl oxide of the -OR4 type, wherein R4 is a saturated or unsaturated and linear or branched hydrocarbon group having 1 to 6 carbon atoms, optionally substituted by a halogen (iodine, bromine, chlorine, fluorine) atom; a hydroxyl (-OH) group; or an ether.

[0133] By way of example, mention may be made of glycidyl (meth)acrylate, hydroxyethyl methacrylate and ethylene glycol, diethylene glycol or polyalkylene glycol (meth)acrylates.

[0134] Among the hydrophobic comonomers which do not contain aliphatic chains, mention may be made of, for example, styrene and its derivatives, such as 4-butylstyrene, α-methylstyrene and vinyltoluene; vinyl acetate of the formula CH2=CH-OCOCH3; vinyl ethers of the formula CH2=CHOR, in which R is a saturated or unsaturated and linear or branched hydrocarbon radical having 1 to 6 carbon atoms; acrylonitrile; caprolactone; vinyl chloride and vinylidene chloride; silicone derivatives which give silicone polymers after polymerization, such as methacryloxytris(trimethylsiloxy)silane and silicone methacrylamide; hydrophobic vinyl monomers of the following formula (C):

[0135] [Chemical formula 4]

[0136]

[0137] Wherein R4 is selected from H, -CH3, -C2H5 or -C3H7; X3 is selected from -OR5 type alkyl oxide, wherein R5 is a saturated or unsaturated and linear or branched hydrocarbon group having 1 to 6 carbon atoms.

[0138] Mention may be made, for example, of methyl methacrylate, ethyl methacrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl acrylate, isoboryl acrylate and 2-ethylhexyl acrylate.

[0139] The water-soluble or water-dispersible The polymers preferably have a molar mass in the range from 50 000 g / mol to 10 000 000 g / mol, preferably from 80 000 g / mol to 8 000 000 g / mol and more preferably still from 100 000 g / mol to 7 000 000 g / mol.

[0140] It can be used as a water-soluble or water-dispersible As homopolymers, there are mentioned, for example, crosslinked or non-crosslinked polymers of sodium acrylamido-2-methylpropanesulfonate, for example sold under the trade name Simulgel 800 (CTFA name: sodium polyacryloyldimethyltaurate), crosslinked polymers of ammonium acrylamido-2-methylpropanesulfonate (INCI name: ammonium polyacryloyldimethyltaurate), for example those described in patent EP 0 815 928 B1, and for example those sold under the trade name Hostacerin Products sold by Clariant.

[0141] Preferably, the composition according to the invention comprises Homopolymer.

[0142] For example, the water-soluble or water-dispersible Copolymers mentioned are:

[0143] - cross-linked acrylamide / sodium acrylamido-2-methylpropanesulfonate copolymers, such as the commercial product Sepigel from Seppic The (CTFA name: polyacrylamide / C 13 -C 14 isoparaffin / laureth-7) or as used in the trade name Simulgel 600 sold by Seppic (CTFA name: acrylamide / sodium acryloyldimethyltaurate / isohexadecane / polysorbate 80);

[0144] - Copolymers of vinylpyrrolidone or vinylformamide, for example sold under the name Aristoflex Used in the commercial product sold by Clariant (CTFA name: ammonium acryloyldimethyltaurate / VP copolymer) but neutralized with sodium hydroxide or hydroxide;

[0145] - and copolymers of sodium acrylate, e.g. / sodium acrylate copolymers, for example under the name Simulgel Used in the commercial product sold by Seppic or under the trade name Sepinov EM (CTFA name: Hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer);

[0146] - and hydroxyethyl acrylate, e.g. / hydroxyethyl acrylate copolymers, for example under the name Simulgel used in the commercial products sold by Seppic (CTFA name: Hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer (and) squalane (and) polysorbate 60), or for example the product sold under the name sodium acrylamido-2-methylpropanesulfonate / hydroxyethyl acrylate copolymer, for example the commercial product Sepinov EMT from Seppic (INCI name: Hydroxyethyl Acrylate / Sodium Acryloyldimethyl Taurate Copolymer).

[0147] The preferred water-soluble or water-dispersible Mention may be made of crosslinked acrylamido-2-methylammonium propanesulfonate homopolymers (INCI name: polyacrylammonium dimethylsulfonate), such as those described in patent EP 0 815 928 B1 and sold, for example, by Clariant under the name Hostacerin Products of the type A, cross-linked acrylamide / sodium acrylamido-2-methylpropanesulfonate copolymer, such as the commercial product Sepigel from Seppic The (CTFA name: polyacrylamide / C 13 -C 14 Isoparaffin / laureth-7), or Copolymers of sodium acrylamido-2-methylpropanesulfonate / hydroxyethyl acrylate, such as those sold under the name sodium acrylamido-2-methylpropanesulfonate / hydroxyethyl acrylate copolymer, such as the commercial product Sepinov EMT from Seppic (INCI name: Hydroxyethyl Acrylate / Sodium Acryloyldimethyl Taurate Copolymer).

[0148] Generally, the composition according to the invention may comprise from 0.1% to 8% by weight as dry matter, preferably from 0.2% to 5% and more preferentially from 0.7% to 3% by weight of polyacrylamide and 2-acrylamido-2-methylpropanesulfonic acid polymers and copolymers relative to the total weight of the composition.

[0149] According to a specific embodiment, the hydrophilic gelling agent may be selected from (ii) at least one polysaccharide produced by a microorganism or isolated from algae.

[0150] In particular, the polysaccharide may be chosen from gellan gum, pullulan, dextran, cellulosic sugars and their derivatives, in particular methylcellulose, hydroxyalkylcellulose, ethylhydroxyethylcellulose and carboxymethylcellulose, galactans, carrageenans, agar, biopolysaccharide gums of microbial origin, especially scleroglucan or xanthan gum.

[0151] Advantageously, the polysaccharide may be chosen from carrageenans, in particular kappa-carrageenan, gellan gum, agar, xanthan gum, scleroglucan gum, pullulan and mixtures thereof.

[0152] Preferably, the polysaccharide may be xanthan gum.

[0153] Such gelling agents can be used as dry matter in a proportion of 0.1% to 8% by weight, relative to the total weight of the aqueous phase, in particular 0.1% to 6% by weight, preferably 0.5% to 2.5% by weight, in particular in a proportion of about 1% by weight, or also in a proportion of about 2% by weight, relative to the total weight of the aqueous phase.

[0154] More specifically, the polysaccharides suitable for the present invention can be distinguished according to whether they are from microorganisms or from algae.

[0155] Polysaccharides produced by microorganisms

[0156] Xanthan gum

[0157] Xanthan gum is a heteropolysaccharide produced on an industrial scale by aerobic fermentation of the bacterium Xanthomonas campestris. Its structure consists of a main chain of β-D-glucose linked by β(1,4)-links, similar to cellulose. One of the two glucose molecules carries a trisaccharide side chain consisting of α-D-mannose, β-D-glucuronic acid and a terminal β-D-mannose e. The internal mannose residues are usually acetylated on carbon 6. About 30% of the terminal mannose residues carry a pyruvate group bonded in chelate form between carbon 4 and carbon 6. The charged pyruvate and glucuronic acid are ionizable and are therefore responsible for the anionic nature of xanthan gum (negative charge drops to pH equal to 1). The content of pyruvate and acetate residues varies depending on the bacterial strain, the fermentation process, post-fermentation conditions and the purification stage. These groups can be oxidized in commercial products by using Na + , K + or Ca 2 + Ion Neutralization (Satia, 1986). The neutralized form can be converted to the acidic form by ion exchange or by dialysis against an acidic solution.

[0158] For an aqueous solution containing 1% xanthan gum, the molecular weight of the xanthan gum is 1 000 000 to 50 000 000 and the viscosity is 0.6 to 1.65 Pa·s (measured at 25° C. using a Brookfield viscometer, LVT type, at 60 rpm).

[0159] Xanthan gum is represented, for example, by the product sold under the name Rhodicare by Rhodia Chimie, TM Products sold under the name Cargill Texturizing Solutions (for the food, beauty and pharmaceutical industries) and under the name Novaxan TM Products sold by ADM under the name Rhodicare The product sold by PMC Ouvrie under the trade name and Name of product sold by CP-Kelco.

[0160] Advantageously, the composition according to the invention comprises xanthan gum.

[0161] One or more xanthan gums may be used in a proportion of 0.1% to 5% by weight of dry matter relative to the total weight of the composition, in particular 0.5% to 3% by weight, preferably 0.5% to 2% by weight relative to the total weight of the composition.

[0162] Pullulan

[0163] Pullulan is a polysaccharide composed of maltotriose units, known by the name α(1,4)-α(1,6)-glucan. The three glucose units in maltotriose are linked by α(1,4) glycosidic bonds, while consecutive maltotriose units are linked to each other by α(1,6) glycosidic bonds.

[0164] For example, pullulan is produced according to the reference Pullulan PF 20 by the Japanese Hayashibara Group.

[0165] Dextran and Dextran Sulfate

[0166] Dextran is a neutral polysaccharide with no charged groups, is biologically inert, and is produced by fermentation of beet sugars containing only hydroxyl groups.

[0167] It is possible to obtain dextran fractions of different molecular weight from natural dextran by hydrolysis and purification. Dextran can in particular be provided in the form of dextran sulfate.

[0168] Dextran is represented, for example, by the products sold under the name Dextran or Dextran T by Pharmacosmos or under the name Dextran 40 Powder or Dextran 70 Powder by Meito Sangyo Co. Dextran sulfate is sold under the name Dextran sulfate by PK Chemical A / S.

[0169] Succinoglycan

[0170] Succinoglycan is an exopolymer produced by bacterial fermentation, of high molecular weight and composed of octasaccharide repeating units (repeats of 8 sugars). Succinoglycan is sold, for example, under the name Rheozan by Rhodia.

[0171] Scleroglucan

[0172] Scleroglucan is a nonionic branched homopolysaccharide composed of β-D-glucan units. The molecule consists of a main straight chain, which is formed by D-glucose units connected by β (1,3) bonds and one-third of the molecular

[0173] It is linked to the D-glucose side unit via a β(1,6) bond.

[0174] A more complete description of scleroglucan and its preparation may be found in document US Pat. No. 3,301,848.

[0175] Scleroglucan is sold, for example, under the name Amigel by Alban Muller or as Actigum TM The CS name was sold by Cargill.

[0176] Gellan Gum

[0177] Gellan gum is an anionic linear heteropolysaccharide based on oligosaccharide units consisting of 4 monosaccharides (tetrasaccharides). D-glucose, L-rhamnose and D-glucuronic acid are present in gellan gum as monomer elements in a ratio of 2:1:1.

[0178] It is sold, for example, under the name Kelcogel CG by CP Kelco.

[0179] Polysaccharides isolated from algae

[0180] Galactan

[0181] The polysaccharide according to the invention may be a galactan specifically selected from agar or carrageenan.

[0182] Carrageenans are anionic polysaccharides constituting the cell walls of various red algae (Rhodophyceae) belonging to the families Gigartinacae, Hypneaceae, Furcellariaceae and Polyideaceae. They are usually obtained by hot water extraction from natural strains of said algae. These linear polymers formed of disaccharide units consist of two D-galactopyranose units linked alternately via α(1,3) and β(1,4) bonds. They are highly sulfated (20-50%) polysaccharides, and the α-D-galactopyranosyl residues can be in the 3,6-anhydro form. Depending on the number and position of the ester-sulfate groups on the repeating disaccharide of the molecule, several types of carrageenans are distinguished, namely: kappa-carrageenan containing one ester-sulfate group, theta-carrageenan containing two ester-sulfate groups, and lambda-carrageenan containing three ester-sulfate groups.

[0183] Carrageenan consists essentially of potassium, sodium, magnesium, triethanolamine and / or calcium salts and polysaccharide ester-sulfate salts.

[0184] Carrageenan is especially available from Seppic as Name sold by Gelymar and Sold by Cargill as Satiagel TM and Satiagum TM Sold under the name and by CP-Kelco and Name for sale.

[0185] Agarogalactans are galactose polysaccharides contained in the cell walls of some species of red algae (Rhodophyceae). They consist of a polymeric group whose basic backbone is a chain of β(1,3)-D-galactopyranose and α(1,4)-L-3,6-anhydrogalactose, with these units repeating regularly and alternating. The differences within the agaro family are due to the presence or absence of solvating methyl or carboxyethyl groups. These mixed structures are usually present in different percentages, depending on the species of algae and the season of harvest.

[0186] Agar is 40 000 to 300 000 g.mol -1 A mixture of high molecular weight polysaccharides (agarose and agaropectin). It is obtained by making an algae extract, usually sterilized by autoclaving, and by treating this liquid, which contains about 2% agar.

[0187] Agar is produced, for example, by the B&V Agar Producers group under the names Gold Agar, Agarite and Grand Agar by Hispanagar and under the names Agar-Agar, QSA (Quick Soluble Agar) and Puragar by Setexam.

[0188] Fulgur

[0189] Fusarium sulphate is commercially available from the red alga Furcellaria fasztigiata. Fusarium sulphate is produced, for example, by Est-Agar.

[0190] According to a specific embodiment, the hydrophilic gelling agent may be selected from (iii) at least one of cellulose or a derivative thereof.

[0191] Cellulose and derivatives

[0192] Among the cellulose derivatives, mention may be made of cellulose ethers or esters (such as methylcellulose, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxymethylpropylcellulose, cellulose acetate, nitrocellulose or nitrocellulose).

[0193] The composition according to the invention may also contain an associative polymer based on cellulose. According to the invention, the term "cellulose-based compound" is understood to mean any polysaccharide compound having in its structure a linear sequence of anhydropyranose glucose residues linked together by β(1,4) glycosidic bonds. The repeating unit is a cellobiose dimer. AGU exists in a chair conformation and has three hydroxyl functions: two secondary alcohols (in positions 2 and 3) and one primary alcohol (in position 6). The polymer thus formed is held together by intermolecular bonds of the hydrogen bond type, thus giving the cellulose a fibrillar structure (approximately 1500 molecules per fiber).

[0194] The degree of polymerization varies greatly depending on the cellulose source; its values ​​can range from a few hundred to tens of thousands.

[0195] Cellulose exhibits the following chemical structure:

[0196] [Chemical formula 5]

[0197]

[0198] The hydroxyl groups of cellulose can react partially or completely with various chemical reagents to obtain cellulose derivatives with intrinsic properties. Cellulose derivatives can be anionic or nonionic. Among these derivatives, cellulose ethers, cellulose esters and cellulose ether esters are distinguished.

[0199] Among the nonionic cellulose ethers there may be mentioned alkylcelluloses such as methylcellulose and ethylcellulose; hydroxyalkylcelluloses such as hydroxymethylcellulose, hydroxyethylcellulose and hydroxypropylcellulose; and mixed hydroxyalkylalkylcelluloses such as hydroxypropylmethylcellulose, hydroxyethylmethylcellulose, hydroxyethylethylcellulose and hydroxybutylmethylcellulose.

[0200] Among the anionic cellulose ethers, mention may be made of carboxyalkylcellulose and its salts. Mention may be made, for example, of carboxymethylcellulose, carboxymethylmethylcellulose and carboxymethylhydroxyethylcellulose and its sodium salt.

[0201] Among the cellulose derivatives, mention may also be made of:

[0202] - Cellulose modified with groups containing at least one fatty chain, for example with groups containing at least one fatty chain (for example alkyl, especially C8-C 22 Hydroxyethylcellulose modified with alkyl, arylalkyl or alkylaryl groups, such as those sold by Ashland Plus Grade 330CS(C 16 alkyl), and

[0203] - Cellulose modified with polyalkylene glycol ether groups, such as the product Amercell Polymer HM-1500 (nonylphenol polyethylene glycol (15) ether) sold by Amerchol.

[0204] Cellulose esters include cellulose inorganic esters (nitric acid, sulfuric acid, phosphoric acid cellulose, etc.), cellulose organic esters (cellulose monoacetate, cellulose triacetate, cellulose amidopropionate, cellulose acetate butyrate, cellulose acetate propionate and cellulose acetate trimellitate, etc.), and mixed cellulose organic / inorganic esters such as cellulose acetate butyrate sulfate and cellulose acetate propionate sulfate. Among the cellulose ether esters, hydroxypropyl methylcellulose phthalate and ethyl cellulose sulfate may be mentioned.

[0205] The cellulose-based compound of the present invention may be selected from unsubstituted cellulose and substituted cellulose.

[0206] Cellulose and derivatives are represented, for example, by the following: (Microcrystalline cellulose, MCC) is a product sold by FMC Biopolymers under the name (Carboxymethyl cellulose) A product sold by Noviant (CP-Kelco) under the name Akucell (Sodium carboxymethylcellulose) A product sold by Akzo Nobel under the name Aquasorb 500 The product sold by Ashland (sodium carboxymethylcellulose) under the name Methocel TM (cellulose ether) and Ethocel TM (Ethylcellulose) is a product sold by Dow under the name (Carboxymethyl cellulose and sodium carboxymethyl cellulose), (Methylcellulose), Blanose TM (Carboxymethyl cellulose), (Methylcellulose, Hydroxypropyl Methylcellulose), (Hydroxypropylcellulose) and (cetyl hydroxyethyl cellulose), sold under the name Plus 330CS is manufactured by Ashland (Alkyl (C 14 / 16 )Hydroxyethylcellulose) is sold under the name 250HHR CS is a product sold by Ashland (hydroxyethyl cellulose (MW: 1 300 000)) and sold by Hercules Aqualon CS (hydroxyethyl cellulose).

[0207] According to a specific embodiment, the composition of the present invention is particularly known under the trade name 250HHRCS Hydroxyethylcellulose sold by Ashland or also particularly under the trade name Aquasorb 500% carboxymethylcellulose sold by Ashland was used in the presence of sodium carboxymethylcellulose.

[0208] Cellulose or its derivatives may be used in a proportion of 0.1% to 5% by weight of dry matter relative to the total weight of the composition, in particular 0.5% to 3% by weight, preferably 1% to 2.5% by weight relative to the total weight of the composition.

[0209] Again according to a specific embodiment, the hydrophilic gelling agent may be selected from (iii) at least one carboxyvinyl polymer.

[0210] Carboxyvinyl polymer

[0211] The modified or unmodified carboxyvinyl polymer may be a copolymer resulting from the polymerization of at least one monomer (a) selected from α,β-ethylenically unsaturated carboxylic acids or esters thereof and at least one ethylenically unsaturated monomer (b) containing a hydrophobic group.

[0212] The term "copolymer" is understood to mean both copolymers obtained from two monomers and those obtained from more than two monomers, for example terpolymers obtained from three monomers.

[0213] Their chemical structure more particularly comprises at least one hydrophilic unit and at least one hydrophobic unit. The term "hydrophobic group" or "hydrophobic unit" is understood to mean a group having a saturated or unsaturated and linear or branched hydrocarbon chain containing at least 8 carbon atoms, preferably 10 to 30 carbon atoms, in particular 12 to 30 carbon atoms and more preferentially 18 to 30 carbon atoms.

[0214] Preferably, these copolymers are chosen from copolymers resulting from the polymerization of:

[0215] - at least one monomer of the following formula (1):

[0216] [Chemical formula 6]

[0217]

[0218] wherein R1 represents H or CH3 or C2H5, i.e., acrylic acid, methacrylic acid or ethacrylic acid monomer, and

[0219] - at least one monomer corresponding to the following formula (2):

[0220] [Chemical formula 7]

[0221]

[0222] wherein R2 represents H or CH3 or C2H5 (ie acrylate, methacrylate or ethacrylate unit) and preferably H (acrylic acid unit) or CH3 (methacrylate unit), and R3 is a hydrogen atom.

[0223] According to a preferred embodiment, these polymers are crosslinked.

[0224] Among copolymers of this type, use is more particularly made of polymers resulting from the polymerization of monomers comprising:

[0225] - basically acrylic,

[0226] - a compound of the above formula (2), wherein R2 represents H or CH3, and R3 is a hydrogen atom,

[0227] - Crosslinking agents which are known copolymerizable unsaturated polyethylenic monomers, such as diallyl phthalate, allyl (meth)acrylate, divinylbenzene, (poly)ethylene glycol dimethacrylate and methylenebisacrylamide.

[0228] According to a particular embodiment of the invention, the carboxyvinyl polymers used in the context of the invention are unmodified. They are in particular homopolymers.

[0229] Among the carboxyvinyl polymers, mention may also be made of sodium polyacrylates, for example available under the name Cosmedia Those sold containing 90% dry matter and 10% water, or Cosmedia as an inverse emulsion containing about 60% dry matter, oil (hydrogenated polydecene) and surfactant (PPG-5 Laureth-5) Both are sold by BASF.

[0230] Mention may also be made of partially neutralized sodium polyacrylates in the form of inverse emulsions comprising at least one polar oil, for example those sold under the name EM is sold by BASF.

[0231] The modified or unmodified carboxyvinyl polymers may also be chosen from crosslinked (meth)acrylic acid homopolymers.

[0232] Within the meaning of this patent application, the term "(meth)acrylic acid" is understood to mean "acrylic acid or methacrylic acid".

[0233] Mention may be made of, for example, those sold under the name Carbopol 910, 934, 940, 941, 934P, 980, 981, 2984 or 5984 by Lubrizol or under the name K. L or Those sold by M.

[0234] According to another particular embodiment of the invention, mention may be made, among the carboxyvinyl polymers, of crosslinked acrylic acid homopolymers. Among the carboxyvinyl polymers that may be used more particularly in the context of the present invention, mention may be made in particular of the Carbopol sold by Lubrizol (CTFA name: Carbomer). Among this type of homopolymers, mention may be made of those crosslinked by allyl ethers of alcohols of the sugar series, such as the products sold under the names Carbopol 980, 981, 954, 2984 and 5984 by Lubrizol, or under the name M and K products sold by 3V.

[0235] Such acrylic acid homopolymers may be present in the composition in particulate or non-particulate form. When they are provided in particulate form, their average size in the hydrated state is preferably less than or equal to 10 μm, and more preferably still less than or equal to 5 μm. Their average size in the dry or non-hydrated state is preferably less than or equal to 2 μm, preferably less than or equal to 1 μm.

[0236] Preferably, the acrylic acid homopolymer is present in non-particulate form.

[0237] Preferably, at least partially neutralized homopolymers of acrylic acid are used. The homopolymers used according to the invention can be chosen in particular from sodium polyacrylate and potassium polyacrylate. Preference is given to using sodium polyacrylate.

[0238] As these acrylic acid polymers which have been neutralized before use, there may be mentioned, for example:

[0239] - sodium polyacrylate, for example under the name Cosmedia Those sold containing 90% dry matter and 10% water, or Cosmedia as an inverse emulsion containing about 60% dry active material, oil (hydrogenated polydecene) and surfactant (PPG-5 Laureth-5) Both are sold by BASF;

[0240] - partially neutralized sodium polyacrylates, in particular in the form of inverse emulsions containing at least one polar oil, for example those known under the name EM sold by BASF; and

[0241] - mixtures thereof.

[0242] More particularly the unmodified carboxyvinyl polymer may be present in a proportion of 0.1 to 5% by weight of dry matter relative to the weight of the aqueous phase, in particular 0.3 to 3%, preferably 0.5 to 2% by weight relative to the weight of the aqueous phase.

[0243] The gelling agents mentioned above may also be present in the composition according to the invention as a mixture.

[0244] According to a specific embodiment of the present invention, the hydrophilic gelling agent is selected from cross-linked acrylamide-2-methylpropanesulfonic acid ammonium polymer, cross-linked acrylamide / acrylamide-2-methylpropanesulfonic acid sodium copolymer, and hydroxyethyl acrylate copolymer, xanthan gum, carboxymethyl cellulose or one of its salts, C8-C 22 Alkyl group-modified hydroxyethyl cellulose, sodium polyacrylate, cross-linked (meth)acrylic acid homopolymer, and mixtures thereof.

[0245] Additional gelling agents may also be present in the composition according to the invention. It is a routine operation for a person skilled in the art to adjust the nature and amount of such additional gelling agents present in the composition according to the invention so that the desired cosmetic properties are not thereby affected.

[0246] Water Phase

[0247] The aqueous phase comprises water and optionally a water-soluble solvent.

[0248] According to the invention, the term "water-soluble solvent" is understood to mean a compound which is liquid at ambient temperature and miscible with water (miscibility in water greater than 50% by weight at 25°C and atmospheric pressure).

[0249] The water-soluble solvents useful in the compositions of the present invention may also be volatile.

[0250] Among the water-soluble solvents that can be used in the composition according to the invention, mention may in particular be made of lower monoalcohols having 1 to 5 carbon atoms, such as ethanol and isopropanol, diols having 2 to 8 carbon atoms, such as ethylene glycol, hexylene glycol, propylene glycol, 1,3-butanediol and dipropylene glycol, C3 and C4 ketones and C2-C4 aldehydes.

[0251] According to an alternative embodiment, the aqueous phase of the composition according to the invention may comprise at least one C2-C 32 Polyols.

[0252] Within the meaning of the present invention, the term "polyol" is understood to mean any organic molecule comprising at least two free hydroxyl groups.

[0253] Preferably, the polyols according to the invention are present in liquid form at ambient temperature.

[0254] The polyols suitable for the invention may be saturated or unsaturated compounds carrying at least two —OH functions, in particular at least three —OH functions and more particularly at least four —OH functions on the alkyl chain and of linear, branched or cyclic alkyl type.

[0255] Suitable polyols for formulating the compositions according to the invention are especially those exhibiting in particular from 2 to 32 carbon atoms, preferably from 3 to 16 carbon atoms.

[0256] The polyol may be selected, for example, from ethylene glycol, pentaerythritol, trimethylolpropane, propylene glycol, dipropylene glycol, 1,3-propanediol, butanediol, isoprene glycol, pentanediol, hexanediol, caprylyl glycol, glycerol, polyglycerols, such as glycerol oligomers, such as diglycerol, polyethylene glycol, and mixtures thereof.

[0257] According to a preferred embodiment of the present invention, the polyol is selected from ethylene glycol, pentaerythritol, trimethylolpropane, propylene glycol, dipropylene glycol, caprylyl glycol, glycerol, polyglycerol, polyethylene glycol and mixtures thereof.

[0258] According to a preferred embodiment, the composition of the invention comprises at least glycerol.

[0259] Preferably, the composition according to the invention comprises from 2% to 20% by weight of glycerol, in particular from 3% to 15% and more preferentially from 4% to 10% by weight of glycerol relative to the total weight of the composition.

[0260] Preferably, the aqueous phase is present in the composition according to the invention in a content ranging from 85% to 100% by weight, preferably from 90% to 100% by weight and more preferentially from 98% to 100% by weight relative to the total weight of the composition.

[0261] When the composition is in the form of a hydrogel, it may advantageously be provided in the form of a threshold hydrogel.

[0262] In the context of the present invention, the term "threshold hydrogel" or "threshold gel" is understood to mean a hydrogel, the flow of which occurs only above a certain stress value applied to the hydrogel, called the yield point, yield value, yield stress, critical stress or threshold stress. In other words, the hydrogel reacts as a solid at this threshold stress (it does not deform or reacts elastically, returning to its initial state after the stress). However, above this threshold stress, it behaves as a fluid gel and flows.

[0263] Fat phase

[0264] The composition according to the invention may contain at least one water-immiscible liquid organic phase, called fatty phase. Such fatty phase may thus be contained in an amount ranging up to 10% by weight relative to the total weight of the composition.

[0265] When it is present, it generally comprises one or more hydrophobic compounds, making said phase water-immiscible. This phase is liquid (in the absence of a structurant) at ambient temperature (20-25°C). Preferentially, the water-immiscible liquid organic phase according to the invention comprises at least one volatile oil and / or one non-volatile oil and optionally at least one structurant.

[0266] In the context of the present invention, the term "oil" means oil at ambient temperature (25°C) and atmospheric pressure (760 mmHg, i.e. 1.05 x 10 5 Pa) is a fatty substance that is liquid below 4000 Pa.

[0267] The oil may be chosen from any physiologically acceptable oil and in particular cosmetically acceptable oil, in particular mineral, animal, vegetable or synthetic oils; in particular hydrocarbon oils, volatile or non-volatile, and / or silicone and / or fluorinated oils, and mixtures thereof.

[0268] As examples of oils that can be used in the present invention, mention may be made of:

[0269] i) hydrocarbon vegetable oils, for example liquid triglycerides of fatty acids having 4 to 24 carbon atoms, for example caprylic / capric triglycerides, for example those sold by Stearineries Dubois or those sold under the names Miglyol 810, 812 and 818 by Dynamit Nobel, or jojoba oil;

[0270] ii) linear or branched hydrocarbons of mineral or synthetic origin, for example liquid paraffin and its derivatives, liquid petroleum, polydecene, polybutene, hydrogenated polyisobutene, for example Parleam or squalane;

[0271] iii) synthetic ethers having 10 to 40 carbon atoms;

[0272] iv) All synthetic esters, such as isononyl isononanoate, isopropyl myristate, isopropyl palmitate, C benzoate 12 To C 15 Alkyl esters (list to be expanded), silicone oils, such as non-volatile polydimethylsiloxane (PDMS), either linear (dimethicone) or cyclic (cyclomethicone);

[0273] v) lipophilic derivatives of amino acids, for example isopropyl lauroyl sarcosinate (INCI name: IsopropylLauroyl Sarcosinate), sold under the name Eldew SL 205 by Ajinomoto; and

[0274] vi) mixtures thereof.

[0275] additive

[0276] The composition according to the invention may additionally comprise at least one additive chosen from the customary adjuvants in the cosmetic field, such as protective agents, fragrances, colorants, polar additives or chelating agents.

[0277] Of course, the person skilled in the art will take care to choose this or these optional additional compounds and / or their amounts such that the advantageous properties of the composition according to the invention are not or not substantially adversely affected by the intended addition.

[0278] The composition according to the invention may also contain other active ingredients, such as peeling dissolving agents, depigmenting agents or propigmenting agents, anti-glycation agents, anti-inflammatory agents or soothing agents, healing agents, hydrating agents, moisturizing agents, anti-pollution agents, anti-aging agents, agents that stimulate the synthesis of dermal or epidermal macromolecules and / or prevent their decomposition, agents that stimulate the proliferation of fibroblasts and / or keratinocytes or stimulate the differentiation of keratinocytes, skin relaxants, firming agents, agents that act on microcirculation, agents that act on cellular energy metabolism, degreasing agents, UV screeners, odor absorbers or mixtures of these.

[0279] According to a preferred embodiment, the composition according to the invention comprises, in addition to the short-chain fatty acid salt, in particular in addition to sodium propionate, at least one additional cosmetic active agent, in particular at least two additional cosmetic active agents and preferably at least three additional cosmetic active agents.

[0280] In particular, the additional cosmetic active agent may be at least one hydrophilic active agent.

[0281] "Hydrophilic active agent" is understood to mean a water-soluble or water-dispersible active agent that is capable of forming hydrogen bonds.

[0282] As hydrophilic active agents there may be mentioned, for example, moisturizers, skin depigmenting agents, exfoliating dissolving agents, humectants, anti-aging agents, mattifying agents, healing agents, antibacterial agents and mixtures thereof.

[0283] The one or more additional hydrophilic active agents may be chosen in particular from:

[0284] - vitamins and their derivatives, especially niacinamide (vitamin B3);

[0285] - humectants, for example urea, hydroxyurea, glycerol, polyglycerol, glyceryl glucoside, diglyceryl glucoside, polyglyceryl glucoside and xylosyl glucoside, and in particular glycerol;

[0286] - C-glycoside compounds, such as those described in document WO 02 / 051828; preferably, the C-glycoside suitable for the present invention is C-β-D-xylopyranoside-2-hydroxypropane, whose INCI name is hydroxypropyltetrahydropyranol, in particular under the name Mexoryl or Mexoryl Sold by Chimex;

[0287] - Antioxidant compounds;

[0288] - in addition in particular anti-aging active agents, such as hyaluronic acid compounds, and in particular sodium hyaluronate, salicylic acid compounds and especially 5-(n-octanoyl)salicylic acid (octylsalicylic acid), adenosine, C-β-D-xylopyranoside-2-hydroxypropane and (3-hydroxy-2-pentylcyclopentyl)acetic acid sodium salt; and

[0289] - mixtures thereof.

[0290] According to another particular embodiment, the composition according to the invention, in addition to its ability to promote sebum secretion, makes it possible to moisturize the skin.

[0291] Purpose of the composition

[0292] The composition according to the invention may be provided in the form of a cosmetic composition for caring for keratin materials, in particular for the skin, preferably for caring for the body or the face, preferably the face.

[0293] These compounds may constitute a protective, treating or caring gel for the face, for the hands or for the body, for example a gel for daytime or nighttime application, or a protective or caring body gel.

[0294] In particular, the composition of the present invention may be provided in the form of an anti-aging care composition for body or facial skin, in particular facial skin.

[0295] The invention therefore also relates to the use of a composition according to the invention for caring for keratin materials, in particular for caring for the skin, preferably for caring for the skin of the body and / or face.

[0296] The invention also relates to a cosmetic method for caring for keratin materials, in particular the skin, comprising at least one stage of applying to said keratin materials a composition as defined above.

[0297] In particular, the composition according to the invention can be employed with the purpose of combating dry skin.

[0298] Dry skin

[0299] Dry skin is primarily characterized by a feeling of discomfort, such as tightness and / or tightness. The dry skin may also feel rough to the touch, and / or appear covered with scales. When the skin is slightly dry, the scales are abundant but barely visible to the naked eye. As the condition worsens, they become fewer and fewer in number, but increasingly visible to the naked eye.

[0300] The causes of dry skin can be either congenital or acquired.

[0301] In a particular embodiment, the composition according to the invention is used for the treatment and / or prevention of non-pathological constitutional dry skin or non-pathological acquired dry skin.

[0302] In the case of acquired dry skin, external parameters, such as exposure to chemical agents, adverse weather conditions or sunlight, or also the involvement of certain other therapeutic treatments (such as retinoic acid), are determining factors. Under these external influences, the skin can become temporarily and locally dry.

[0303] Non-pathological constitutional dry skin is dry skin, the severity of which may depend on the external factors already mentioned. In this category of skins called dry skin are included senile skin (characterized by a general decrease in skin metabolism with age), fragile skin (very sensitive to external factors and often accompanied by erythema and rosacea) and general xerosis (probably of hereditary origin and manifested mainly on the face, limbs and backs of the hands).

[0304] The composition according to the invention therefore proves to be particularly effective for the prevention and / or treatment of dry skin and in particular acquired dry skin and / or constitutional dry skin.

[0305] Non-pathologically acquired constitutional dry skin may be characterized by a deficiency of lipids constituting the hydrolipid barrier and / or membrane, in particular insufficient sebum secretion from endogenous sebaceous glands.

[0306] As mentioned above, less than 100 μg / cm2 measured in the T-zone of the face by the method described in FR 2 368 708 2 A sebum content of 1% can be considered a characteristic of hyposeborrheic dry skin.

[0307] The compositions according to the invention thus prove to be particularly effective in preventing and / or treating hyposeborrheic dry skin.

[0308] In particular, the composition according to the invention can be used for the purpose of combating the signs of skin ageing, in particular by promoting sebum production in aged skin, in particular over 60 years old, indeed even over 65 years old.

[0309] Therefore, the present patent application also relates to the use of the composition according to the invention for combating the signs of skin aging.

[0310] Aging Skin

[0311] The compositions according to the invention prove particularly effective in preventing and / or treating aged skin, and more particularly hyposeborrheic aged skin.As mentioned above, premature aging is known to be due to a lack or deficiency of sebum at the skin surface.

[0312] The term "aged skin" is understood to mean the overall aesthetic state of the skin resulting from chronological aging and / or photoinduced aging.

[0313] More particularly, the present invention is directed to preventing and / or reducing and / or treating the signs of skin aging.

[0314] The term "signs of skin aging" is understood to mean any change in the appearance of the skin due to aging of chronological and / or light-induced origin.

[0315] By way of examples of such changes considered in the present invention, mention may be made of a not very even and not so smooth surface, a thin epidermis, wrinkles and fine lines, shrunken skin, lack of skin elasticity and / or tone, resulting in a sagging and wrinkled skin appearance.

[0316] In particular, the signs of skin aging targeted by the present invention are selected from thinning of the skin, loss of firmness, loss of elasticity, loss of skin density or skin tone, adverse changes in the skin surface appearance, the appearance of noticeable skin micro-reliefs, a rough appearance, the formation and / or presence of fine lines and / or wrinkles, changes in the radiance of the skin tone, a shrunken skin appearance, skin sagging or skin shrinkage.

[0317] Preferably, the skin aging signs targeted by the present invention are selected from the group consisting of thinning of the skin, the appearance of noticeable skin microreliefs, the formation and / or presence of fine lines and / or wrinkles, skin sagging and skin shrinkage.

[0318] More preferably, the skin aging signs targeted by the present invention are selected from the group consisting of the appearance of noticeable skin microreliefs, the formation and / or presence of fine lines and / or wrinkles, skin sagging and skin shrinkage.

[0319] The composition can be applied to the skin by hand or using an applicator.

[0320] Throughout the description including the claims, the expression "comprising / including one" should be understood as being synonymous with "comprising / including at least one" unless otherwise stated.

[0321] Unless otherwise stated, the expressions “between ... and ," “including from ... to ," “formed from ... to ," and “ranging from ... to ," should be understood to include limits.

[0322] The present invention is explained in more detail by the examples and figures given below. Unless otherwise stated, the indicated amounts are expressed as mass percentages.

[0323] Example

[0324] Measurement and evaluation methods

[0325] Stability measurement

[0326] The stability of the compounds was evaluated at 45°C at T = 2 months. It was verified whether phase separation, release or changes in appearance were observed.

[0327] Appearance

[0328] The appearance of the obtained composition was evaluated:

[0329] - by observing its behavior from the perspective of its viscoelastic properties, and

[0330] -By observing its transparent or translucent appearance.

[0331] Different types of gels are thus available:

[0332] - a "threshold gel" as defined above,

[0333] -Flowing gel, on the contrary, will flow no matter what pressure is applied to it.

[0334] It should be noted that the flowing gel exhibits a very low threshold; that is why it flows easily as long as the bottle containing it is tilted.

[0335] Manufacturing method for limiting the formation of unpleasant sour taste

[0336] Regardless of the polymer or gel system used, the cosmetic composition is preferably prepared in several stages:

[0337] 1. Glycerol or any other hydrophilic starting material and protective agent are introduced into water at about 60°C and then the polymer is dispersed all together.

[0338] 2. Before introducing the phase containing sodium propionate (25°C), the pH of the previous phase or phases was adjusted to a pH of 6.3 to 7.

[0339] 3. Adjust the pH of the phase containing sodium propionate to a pH of 6.3 to 7.

[0340] 4. The phase comprising sodium propionate is introduced into the mixture of the previous phase or phases and homogenized at 25° C. During the addition of the phase comprising sodium propionate, a fully acceptable fluidization of the previous phase or phases is observed.

[0341] 5. If necessary, adjust pH to 6.3 to 7.

[0342] Example 1: Preparation of hydrogel

[0343] The hydrogel 1 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as weight percentages relative to the total weight of the composition.

[0344] [Table 1]

[0345]

[0346] The polymer derived from ammonium polyacryloyldimethyltaurate used in this example can achieve appropriate and stable gelation.

[0347] Example 2: Preparation of hydrogel

[0348] The hydrogel 2 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as weight percentages relative to the total weight of the composition.

[0349] [Table 2]

[0350]

[0351] The polyacrylamide-derived polymer used in this example can achieve adequate and stable gelation.

[0352] Example 3: Preparation of hydrogel

[0353] The hydrogel 3 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as weight percentages relative to the total weight of the composition.

[0354] [Table 3]

[0355]

[0356] The polymer hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer used in this example can achieve appropriate gelation.

[0357] Example 4: Preparation of hydrogel

[0358] The hydrogel 4 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as weight percentages relative to the total weight of the composition.

[0359] [Table 4]

[0360]

[0361] The polymer hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer used in this example can obtain appropriate and stable gelation.

[0362] Example 5: Preparation of hydrogel

[0363] The hydrogel 5 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as weight percentages relative to the total weight of the composition.

[0364] [Table 5]

[0365]

[0366] The xanthan gum used in this example can achieve appropriate gelation.

[0367] Example 6: Preparation of hydrogel

[0368] The hydrogel 6 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as percentages by weight relative to the total weight of the composition.

[0369] [Table 6]

[0370]

[0371] The cellulosic polymer used in this example provides adequate gelation.

[0372] Two other cellulose polymers were used in the same gel:

[0373] - By product name Plus 330CS sold by Ashland (C 14 / 16 ) alkyl hydroxyethyl cellulose, and

[0374] -Hydroxyethylcellulose (MW: 1 300 000), sold under the trade name 250 HHR CS is sold by Ashland - see Example 7 below.

[0375] The obtained gel was also satisfactory in terms of appearance and stability at 45°C for 2 months.

[0376] Example 7: Preparation of hydrogel

[0377] The hydrogel 7 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as weight percentages relative to the total weight of the composition.

[0378] [Table 7]

[0379]

[0380] The cellulosic polymer used in this example provides adequate gelation.

[0381] Example 8: Preparation of a composition comprising a mixture of essence-type gels

[0382] The serum 1 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as percentages by weight relative to the total weight of the composition.

[0383] [Table 8]

[0384]

[0385]

[0386] The mixture of xanthan gum, ammonium polyacryldimethyltaurate and a cross-linked acrylic acid copolymer used in this example was able to achieve adequate gelation.

[0387] Example 9: Preparation of a hydrogel comprising a mixture of gelling agents

[0388] The hydrogel 8 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as weight percentages relative to the total weight of the composition.

[0389] [Table 9]

[0390]

[0391]

[0392] The polyacryldimethylammonium taurate and a mixture of polyacryldimethylammonium taurate and sodium polyacrylate used in this example can achieve appropriate gelation.

[0393] Example 10: Preparation of an emulsified gel comprising a mixture of a gelling agent and a cosmetic oil

[0394] An emulsified gel 1 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as percentages by weight relative to the total weight of the composition.

[0395] [Table 10]

[0396]

[0397]

[0398] The polyacryldimethylammonium taurate and the mixture of polyacryldimethylammonium taurate and sodium polyacrylate used in this example can obtain suitable gel and oil dispersions.

[0399] Example 11: Preparation of an emulsified gel comprising a mixture of a gelling agent and a cosmetic oil

[0400] The emulsified gel 2 according to the invention was prepared according to the weight proportions detailed in the table below. The values ​​are expressed as weight percentages relative to the total weight of the composition.

[0401] [Table 11]

[0402]

[0403]

[0404] The polymer hydroxyethyl acrylate / sodium acryloyldimethyl taurate copolymer used in this example has the ability to give suitable gelling and oil dispersions.

[0405] Comparative Example 1

[0406] Acrylate / Acrylic Acid C 10-30 Alkyl ester cross-linked polymer gelling agents, such as Ultrez sold by Lubrizol or Pemulen Its composition is as follows:

[0407] Acrylate / Acrylic C 10-30 Alkyl Esters Crosspolymer 90

[0408] Trideceth-6 5

[0409] PEG-30 dipolyhydroxystearate 5

[0410] [Table 12]

[0411]

[0412]

[0413] Although known to be tolerant to salt, hydrophobically modified acrylic acid polymers (composed of C 10-30 Alkyl chain modification) is incompatible with the obtained hydrogel containing sodium propionate.

Claims

1. A cosmetic composition for caring for keratin materials, comprising: - 0.5 to 4% by weight of sodium propionate, and at least 90% by weight of an aqueous phase, relative to the total weight of the composition, gelled by a hydrophilic gelling agent chosen from: (i) at least one polymer selected from the group consisting of polyacrylamide and 2-acrylamido-2-methylpropanesulfonic acid polymers and copolymers, (ii) at least one polysaccharide produced by a microorganism or isolated from algae, (iii) at least one of cellulose or a derivative thereof, (iv) at least one carboxyvinyl polymer, or (v) a mixture thereof.

2. The cosmetic composition according to claim 1, characterized in that The sodium propionate is present in an amount of 0.8 wt % to 4 wt %.

3. The cosmetic composition according to claim 1, characterized in that The sodium propionate is present in an amount of 1% to 3% by weight.

4. The cosmetic composition according to claim 1, characterized in that The hydrophilic gelling agent is selected from cross-linked acrylamide-2-methylpropanesulfonic acid ammonium polymer, cross-linked acrylamide / acrylamide-2-methylpropanesulfonic acid sodium copolymer, and hydroxyethyl acrylate copolymer, xanthan gum, carboxymethyl cellulose or one of its salts, C8-C 22 Alkyl group-modified hydroxyethyl cellulose, sodium polyacrylate, cross-linked (meth)acrylic acid homopolymer, and mixtures thereof.

5. The cosmetic composition according to claim 1, characterized in that The aqueous phase is gelled by 0.1% to 8% by weight of at least one hydrophilic gelling agent relative to the total weight of the aqueous phase.

6. The composition according to claim 5, characterized in that The pH of the cosmetic composition is 5.8 to 7.

2.

7. The cosmetic composition according to claim 1, characterized in that The aqueous phase comprises water.

8. The cosmetic composition according to claim 1, characterized in that The composition is provided in the form of a hydrogel, a serum or an emulsified gel.

9. The cosmetic composition according to claim 1, characterized in that The composition comprises at least one additional cosmetic active agent in addition to the sodium propionate.

10. A cosmetic method for caring for keratin materials comprising at least one stage of applying a cosmetic composition as defined in claim 1 to said keratin materials.

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