FR3111555A1 - Composition comprising a polysaccharide, a polyol and at least one polyglycerol ester - Google Patents

Abstract

Composition comprising a polysaccharide, a polyol and at least one polyglycerolated ester The present invention relates to a particularly cosmetic composition comprising, in a physiologically acceptable medium: at least one polysaccharide comprising rhamnose, at least one polyol, at least one ester chosen from fatty acid esters comprising 10 carbon atoms and polyglycerol comprising 4 glycerol units, and fatty acid esters comprising 18 carbon atoms and polyglycerol comprising 2 glycerol units, at least one oil, and at least one surfactant which is a stearate comprising from 20 to 150 units of ethylene oxide. Figure for abstract: none

Description

Composition comprising a polysaccharide, a polyol and at least one polyglycerolated ester

The present invention relates to a composition, preferably cosmetic, comprising a polysaccharide comprising rhamnose, a polyol, at least one specific polyglycerolated ester, at least one oil, and at least one surfactant which is a stearate comprising from 20 to 150 units of ethylene oxide.

The skin is a tissue whose cells are contiguous, and solidary with each other. The skin tissue forms an outer covering comprising sebaceous or sweat glands, and hair follicles. The skin, and in particular the scalp, are epithelia with continual renewal. Renewal, or desquamation, is a coordinated and finely regulated process resulting in the elimination of superficial cells, in a imperceptible and invisible way.

Human skin consists of two compartments, namely a superficial compartment, the epidermis, and a deep compartment, the dermis.

The epidermis is conventionally divided into a basal layer of keratinocytes constituting the germinative layer of the epidermis, a so-called spiny layer consisting of several layers of polyhedral cells arranged on the germinative layers, one to three so-called granular layers consisting of flattened cells containing distinct cytoplasmic inclusions, the grains of keratohyaline and finally, a set of upper layers called stratum corneum (or stratum corneum ), made up of keratinocytes at the terminal stage of their differentiation called corneocytes.

Corneocytes are anucleate cells mainly made up of a fibrous material containing cytokeratins, surrounded by a horny envelope. There is a permanent production of new keratinocytes to compensate for the continuous loss of epidermal cells at the level of the stratum corneum according to a mechanism called desquamation.

However, an imbalance between the production of cells at the level of the basal layer and the rate of desquamation can in particular lead to the formation of scales on the surface of the skin. Similarly, a lack of terminal differentiation of cells in the stratum corneum , for various reasons, can lead to the formation of large, thick clusters of cells, visible to the naked eye, and called "squames", or in d other situations, to a thinning of the stratum corneum . This can lead to a fragility of the barrier properties of the epidermis, to chronic dehydration of the stratum corneum, a loss of mechanical elasticity, tightness, as well as a lack of radiance and transparency of the skin. By way of example of factors favoring this deterioration in the surface quality of the skin, mention may be made of stress, the winter period, excess sebum, lack of hydration; this may also be the case for the dry skin of elderly subjects.

Thus, a fragility of the skin barrier can occur in the presence of external aggressions such as irritating agents (detergents, acids, bases, oxidants, reducers, concentrated solvents, harmful gases or fumes), mechanical stresses (friction, shocks, abrasion, tearing of the surface, projection of dust, particles, shaving or depilation), thermal or climatic imbalances (cold, dryness, radiation), xenobiotics (undesirable micro-organisms, allergens) or internal attacks of the psychological stress type.

One of the critical steps in the stratum corneum terminal differentiation process is the cross-linking of protein precursors to the corneal envelope. This phenomenon plays an essential role in the development and maintenance of cutaneous cohesion and the physical properties of the skin such as the barrier function.

The horny envelope is an essential component of corneocytes.

The maturation of the corneal envelope from the deep layers to the superficial layers of the stratum corneum can be characterized by morphological and biophysical or mechanical parameters.

The hydrating active agents conventionally used, such as humectants, hydrating polymers or fatty substances such as petroleum jelly, temporarily modify the surface properties of the skin. These active ingredients can lead to a mechanical softening of the stratum corneum, an increase in its state of hydration and/or an improvement in the microrelief of the skin by the formation of a film on the surface of the skin. Generally, these effects are not persistent over time and only last a few hours. In addition, after cleaning the skin, these active ingredients are eliminated and the mechanical softening effect of the skin, the improvement in the texture of the skin or its optical properties disappear.

Furthermore, the use of film formers on the skin, in particular the use of humectant polysaccharides such as carrageenan, often leads to a "tensor" effect of the skin, an increase in the elastic modulus of the skin; this surface stiffening leads to skin discomfort.

There is therefore a need for compositions that improve the state of hydration of the skin, in particular dry or aged skin, by avoiding tightness and feelings of discomfort when they are applied to the skin.

There is also a need for compositions which give the skin a plumping effect and/or a plump appearance. By “plumped appearance”, we mean a remodeling effect on the skin. The skin is smoother and has a fuller appearance, which is maintained even after pressure on the skin with the finger.

The inventors have now discovered that the combination of a particular polysaccharide, i.e. comprising rhamnose, with a polyol and at least one specific polyglycerolated ester, in a composition comprising at least one oil and at least one stearate comprising from 20 to 150 units of ethylene oxide, makes it possible to soften the skin in a satisfactory manner and to give it a plumping effect and a plump appearance.

Thus, the subject of the present invention is a composition comprising, in a physiologically acceptable medium:

at least one polysaccharide comprising rhamnose,

at least one polyol,

at least one ester chosen from fatty acid esters comprising 10 carbon atoms and polyglycerol comprising 4 glycerol units, and fatty acid esters comprising 18 carbon atoms and polyglycerol comprising 2 glycerol units,

at least one oil, and

at least one surfactant which is a stearate comprising from 20 to 150 units of ethylene oxide.

The composition according to the invention is preferably cosmetic.

By “physiologically acceptable”, is meant a medium compatible with keratin materials.

A subject of the present invention is also a cosmetic process for caring for keratin materials, preferably the skin, comprising the application to said keratin materials of a composition according to the invention.

A subject of the present invention is also the cosmetic use of a composition according to the invention for softening the skin, in particular the stratum corneum.

Polysaccharide comprising rhamnose

The composition according to the invention comprises at least one polysaccharide comprising rhamnose.

Preferably, the polysaccharide according to the invention comprises a rhamnose content ranging from 10% to 100% by weight relative to the total weight of the polysaccharide, preferably from 20% to 70% by weight, preferably from 40% to 60% in weight.

Preferably, the polysaccharide according to the invention is not sulphated. By “unsulphated”, is meant that the degree of sulphation of the polysaccharide is less than 0.5% by weight, preferably less than 0.1% by weight relative to the weight of the polysaccharide. Preferably, the sulfation rate is zero.

Thus, preferably, the polysaccharide according to the invention is such that the repetitive elements which constitute it mainly contain rhamnose. Preferably, the repeating elements comprise at least the components of general formula I:

wherein Rh is a rhamnose molecule, Rh* is a branched rhamnose molecule, O is a hexoside or pentoside sugar molecule, U is a uronic acid molecule and n is between 1 and 100, preferably between 5 and 65.

By “repetitive elements containing mainly rhamnose”, is meant a branched sequence comprising at least 50% of rhamnose of the D and/or L series, as well as its α and/or β isomers.

The sugar O can in particular be chosen from fucose, galactose, ribose, arabinose, xylose and mannose.

By uronic acid U is meant any hexose oxidized on its primary alcohol function to carboxylic acid, in particular glucuronic acid, galacturonic acid, mannuronic acid or iduronic acid.

According to a particular embodiment of the invention, the branched rhamnose molecule can be fixed by an osidic bond from its carbon 1 to a free carbon of one of the molecules of sugar O or of uronic acid U or of rhamnose Rh of the saccharide chain, especially on carbons 2 or 3.

According to another particular embodiment, the repetitive elements may in particular consist of the sequence of general formula II:

in which Rh is a molecule of rhamnose, O is a molecule of a hexoside or pentoside sugar, U is a molecule of uronic acid and the ramification of the rhamnose on the ose O is done according to an osidic bond (1→2) or (1→3).

According to a particularly advantageous embodiment, the sugar O is galactose and the uronic acid U is glucuronic acid. Preferably, the sequence has a sequence containing 3 molecules of rhamnose, one of which is branched, 2 molecules of galactose and one molecule of glucuronic acid. According to formula II, n represents a value such that this polysaccharide has a molecular weight of the order of 50,000 daltons. It can be obtained from cultures of bacteria of the Klebsiella type, in particular Klebsiella pneumoniae and in particular the I-714 strain (deposited at the CNCM - National Collection of Microorganism Culture - under number I-714) according to a process described below. . Advantageously, this polysaccharide has the rhamnose branching on the galactose in position V. It emerges that this polysaccharide is more particularly made up of the following repeating unit: →4)- α-L-Rhap(1→3)- β-D- Galp(1→2)- α-L-Rhap(1→4)- β-D-GlcpA(1→3)- [α-L-Rhap(1→2)]- α-D-Galp(1→ .

The hydrolysis of this polysaccharide also makes it possible to obtain a mixture of fractions of lower molecular weight, in particular the major fractions of 5,000 daltons and 13,000 daltons, which may be purified and which are particularly advantageous according to the invention.

According to another particular embodiment, the repetitive elements may in particular consist of the sequence of general formula III:

in which Rh is a molecule of rhamnose, O is a molecule of a hexoside or pentoside sugar, U is a molecule of uronic acid and the ramification of the rhamnose on the rhamnose is done according to an osidic bond (1→3). According to a particularly advantageous embodiment, the sugar O is glucose and the uronic acid U is glucuronic acid, preferably according to a sequence containing 3 molecules of rhamnose, one of which is branched, a molecule of glucose and a molecule of acid glucuronic. Such a polysaccharide can in particular be obtained according to the method described below from a culture of bacteria of the Klebsiella planticola type, in particular strain I-2743 (deposited at the CNCM under number I-2743). Advantageously, such a polysaccharide has the rhamnose branching on the rhamnose in position III. It appears that this polysaccharide is more particularly made up of the following repeating unit: →3)- β-L- Rhap(1→4)- β-D-Glcp(1→2)- [α-L- Rhap(1 →3)]-α-L-Rhap(1→4)-α-D-GlcpA(1→.

The hydrolysis of this polysaccharide also makes it possible to obtain a mixture of fractions of lower molecular weight, in particular the majority fraction of 5,000 daltons, which may be purified and which is particularly advantageous according to the invention.

In general, the polysaccharides according to the invention can be of bacterial or plant origin. They can be obtained by conventional techniques for the production of polysaccharides (chemical synthesis, enzymatic extraction of exopolysaccharides). According to an advantageous embodiment, the polysaccharides are exopolysaccharides obtained by fermentation of a bacterial strain by producing, of the encapsulated bacteria type, according to a production process such as that detailed in patent FR264522. This method is defined in that a strain of bacteria of the Klebsiella type is cultured in a nutrient medium comprising a carbon source, a preferential nitrogen source and appropriate mineral salts, at a pH of approximately 6 to 8. , at a temperature of about 30 to 35°C, with stirring and aeration, for 4 to 12 days. The carbon/nitrogen ratio is advantageously greater than 5 in order to promote the secretion of the polysaccharide. The polysaccharide can then be isolated by subjecting the fermentation medium to a heat treatment at approximately 70-120° C., for 10 minutes to approximately 1 hour, then by separating it, for example by cold centrifuging it. Exopolysaccharides and cellular polysaccharides are found entirely in the clear supernatant phase. If necessary, the polysaccharides can be purified by precipitation by addition of a non-solvent organic liquid such as acetone or a lower alcohol such as ethanol or propanol, and separated by filtration or centrifugation before being dried.

The isolated polysaccharides can thus easily be incorporated into a composition, as such or in hydrolyzed form. In this case, the hydrolysis can be carried out before drying by known methods such as acid hydrolysis. It can be carried out using a commonly used proton donor, such as hydrochloric acid, at a temperature ranging from 50 to 100° C. and for 30 minutes to 4 hours, depending on the desired size of the fractions. The oligosaccharide fractions thus obtained can be recovered and purified if necessary according to conventional methods.

This protocol can be carried out using bacterial strains producing rhamnose-rich exopolysaccharides, in particular encapsulated bacteria. According to a preferred embodiment of the invention, a strain of Klebsiella bacteria is used, preferably Klebsiella pneumoniae or Klebsiella planticola .

Preferably, the repeating unit of the polysaccharide (exopolysaccharide) according to the invention is that produced by Klebsiella pneumoniae I-714 and called Rhamnosoft®:

The composition of Rhamnosoft® corresponds to a polymer with a branched structure, with a molecular weight of the order of 50,000 daltons, and having a saccharide sequence comprising three molecules of rhamnose (I, III, VI), two molecules of galactose (II, V) and a molecule of glucuronic acid (IV). Rhamnose therefore constitutes 50% of the polysaccharide. The polysaccharide has a rhamnose VI branch on the galactose in the V position.

The structure of the repeating unit is in this case:

→4)- α-L-Rhap(1→3)- β-D-Galp(1→2)- α-L-Rhap(1→4)- β-D-GlcpA(1→3)- [α -L-Rhap(1→2)]-α-D-Galp(1→.

It corresponds to the following detailed formula:

Preferably, the polysaccharide according to the invention is used in aqueous solution at 2.5% by weight of active material, relative to the total weight of solution. Such a polysaccharide is marketed in particular under the name Rhamnosoft® HP 1.5P by Solabia.

Preferably, the polysaccharide may be present in the composition according to the invention in an active ingredient content ranging from 0.001% to 1% by weight, relative to the total weight of the composition, preferably ranging from 0.01% to 0 .5% by weight, and preferably ranging from 0.03% to 0.3% by weight.

Fatty acid ester s and specific polyglycerol

The composition according to the invention also comprises at least one ester chosen from fatty acid esters comprising 10 carbon atoms and polyglycerol comprising 4 glycerol units, and fatty acid esters comprising 18 carbon atoms and polyglycerol comprising 2 units of glycerol.

Preferably, the ester chosen from fatty acid esters comprising 10 carbon atoms and polyglycerol comprising 4 glycerol units and fatty acid esters comprising 18 carbon atoms and polyglycerol comprising 2 glycerol units, according to The invention is a mono- or diester, preferably a mono-ester.

The term "polyglycerol" refers to polymers of glyceryl which are linear chains of units (units) of glycerol.

The esters more particularly considered according to the present invention are esters resulting from the esterification of polyglycerol and carboxylic acid(s) having a carbon chain of given length.

The carboxylic acid can be linear or branched, saturated or unsaturated.

Preferably, it is a linear monocarboxylic acid.

In general, they derive from the esterification of at least one hydroxyl function of a polyglycerol by a carboxylic acid having a carbon chain of given length.

According to a particular embodiment, the esters suitable for the present invention can derive from the esterification of a polyglycerol with one or more carboxylic acids, which are identical or different. It may be a hydroxylated mono-ester, a hydroxylated di-ester, a hydroxylated tri-ester, or a mixture thereof.

The fatty acid ester comprising 10 carbon atoms and of polyglycerol comprising 4 glycerol units is formed (i) from at least one fatty acid comprising an alkyl or alkenyl chain containing 10 carbon atoms (also called C10 fatty acid ), and (ii) 4 glycerol units.

Preferably, the C10 fatty acid is saturated, and contains a linear alkyl chain. Preferably the C10 fatty acid is capric acid.

In a preferred embodiment of the invention, the fatty acid ester comprising 10 carbon atoms and polyglycerol comprising 4 glycerol units is polyglyceryl monocaprate comprising 4 glycerol units, i.e. polyglyceryl-4 monocaprate.

The fatty acid ester comprising 18 carbon atoms and of polyglycerol comprising 2 glycerol units is formed (i) from at least one fatty acid comprising an alkyl or alkenyl chain containing 18 carbon atoms (also called C18 fatty acid ), and (ii) 2 units of glycerol.

Preferably, the C18 fatty acid is unsaturated, and contains a linear alkyl chain. Preferably the C18 fatty acid is oleic acid.

In a preferred embodiment of the invention, the fatty acid ester comprising 18 carbon atoms and polyglycerol comprising 2 glycerol units is polyglyceryl monooleate comprising 2 glycerol units, i.e. polyglyceryl-2 monooleate.

A commercial product based mainly on polyglyceryl-4 monocaprate or PG-4 caprate is available under the trade name TEGOSOFT PC 41 by the company EVONIK GOLDSCHMIDT.

A commercial product based mainly on polyglyceryl-2 monooleate or PG-2 oleate is available under the trade name SUNSOFT Q-17D(G)-C by the company TAIYO KAGAKU.

The fatty acid and polyglycerol ester may be present in the composition according to the invention in a content ranging from 0.5% to 10% by weight, relative to the total weight of the composition, preferably ranging from 1% to 7% by weight, and preferentially ranging from 2% to 6% by weight, and preferentially ranging from 4% to 6% by weight.

Polyol

The composition according to the invention also comprises at least one polyol.

By polyol according to the invention, is meant a hydrocarbon chain comprising at least 2 carbon atoms, preferably from 2 to 50 carbon atoms, preferably from 4 to 20 carbon atoms, preferably having from 2 to 10 carbon atoms. carbon, and preferably having from 2 to 6 carbon atoms, and bearing at least two hydroxy groups. The polyols used in the present invention may have a weight-average molecular mass of less than or equal to 1000, preferably between 90 and 500.

The polyol can be a natural or synthetic polyol. The polyol can have a linear, branched or cyclic molecular structure.

The polyol can be selected from glycerin and derivatives thereof, and glycols and derivatives thereof. The polyol can be selected from the group consisting of glycerin, diglycerin, polyglycerin, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, pentylene glycol, hexylene glycol, 1,3-propanediol , 1,5-pentanediol, octane 1,2-diol, polyethylene glycols, in particular having from 5 to 50 ethylene oxide groups, and sugars such as sorbitol, and mixtures thereof.

More particularly the polyol is glycerin.

Said polyol(s) may be present in a content ranging from 2% to 40% by weight, relative to the total weight of the composition, preferably ranging from 5% to 30% by weight, and preferably ranging from 7% to 25% by weight. Preferably, said polyol(s) is (are) present in a content of at least 10% by weight relative to the total weight of the composition, preferably at least 10%, of preferably from 10% to 30% by weight, and preferably from 10 to 15% by weight.

The composition according to the invention is an emulsion. Indeed, it comprises in particular at least one polyol (which corresponds to a hydrophilic phase), and at least one oil (oily phase). Preferably, the composition according to the invention is an oil-in-water emulsion.

The composition according to the invention comprises at least one surfactant as described below. Typically, it has a cream appearance, in particular an opaque cream.

Surfactants

The composition according to the invention comprises at least one surfactant which is a stearate comprising from 20 to 150 units of ethylene oxide.

Preferably, it also comprises an additional surfactant chosen from C ₁₆ -C ₂₂ fatty acid and sorbitan esters and C ₁₆ -C ₂₂ fatty acid and glyceryl esters.

Stearate with 20 to 150 ethylene oxide units is an ester of fatty acid (stearic acid) and polyethylene glycol (20 to 150 ethylene oxide units, PEG-20 to PEG-150).

The number of ethylene oxide units can range from 20 to 150, preferably from 35 to 120, and better still from 40 to 100.

By way of example of a stearate comprising from 20 to 150 units of ethylene oxide, mention may be made of stearic acid esters comprising respectively 20, 30, 40, 50 or 100 units of ethylene oxide, such as the products marketed respectively under the name Myrj 49 P (polyethylene glycol stearate 20 EO; CTFA name: PEG-20 stearate), Myrj 51, Myrj 52 P (polyethylene glycol stearate 40 EO; CTFA name: PEG-40 stearate), Myrj 53 or Myrj 59 P by the company CRODA.

The stearate comprising from 20 to 150 ethylene oxide units may be present in the composition according to the invention in a content ranging from 0.1% to 10% by weight, relative to the total weight of the composition, and from preferably ranging from 0.1% to 5% by weight, and preferably ranging from 0.25% to 2.5% by weight.

Preferably, the composition according to the invention also comprises an additional surfactant chosen from C ₁₆ -C ₂₂ fatty acid and sorbitan esters and C ₁₆ -C ₂₂ fatty acid and glyceryl esters.

According to a first embodiment of the invention, the composition comprises a C ₁₆ -C ₂₂ fatty acid ester and sorbitan.

C ₁₆ -C ₂₂ fatty acid and sorbitan esters are formed by esterification of at least one fatty acid comprising at least one saturated or unsaturated linear alkyl chain, having respectively from 16 to 22 carbon atoms, with sorbitol . These esters can be chosen in particular from stearates, behenates, arachidates, palmitates, sorbitan oleates, and mixtures thereof. Preferably, sorbitan stearates and palmitates are used, and preferably sorbitan stearates.

The C ₁₆ -C ₂₂ fatty acid ester of sorbitan present in the composition according to the invention is advantageously solid at a temperature less than or equal to 45°C.

Mention may be made, by way of example of a sorbitan ester that can be used in the composition according to the invention, sorbitan monostearate (CTFA name: Sorbitan stearate) sold by the company Croda under the name Span 60, sorbitan tristearate sold by the Croda under the name Span 65 V, sorbitan monopalmitate (CTFA name: Sorbitan palmitate) sold by Croda under the name Span 40, sorbitan monoleate sold by Croda under the name Span 80 V, sorbitan sold by Uniquema under the name Span 85 V. Preferably, the sorbitan ester used is sorbitan tristearate.

The C ₁₆ -C ₂₂ fatty acid ester of sorbitan may be present in the composition according to the invention in a content ranging from 0.01% to 10% by weight, relative to the total weight of the composition, preferably ranging from 0.01% to 5% by weight, and preferentially ranging from 0.25% to 1.5% by weight.

The glyceryl fatty acid ester can be obtained in particular from an acid comprising a saturated linear alkyl chain, having 16 to 22 carbon atoms. As ester of glyceryl and fatty acid, mention may be made in particular of glyceryl stearate (mono-, di- and/or tri-glyceryl stearate) (CTFA name: Glyceryl stearate), glyceryl ricinoleate, and mixtures thereof. Preferably, the glyceryl and fatty acid ester used is chosen from glyceryl stearates.

The glyceryl fatty acid ester may be present in an amount ranging from 0.1 to 10% by weight, relative to the total weight of the composition, preferably ranging from 0.1 to 5% by weight, and preferably ranging from 0.4% to 3% by weight.

The composition of the invention may in particular comprise a mixture of glyceryl stearate and of polyethylene glycol monostearate 100 EO, and in particular that comprising a 50/50 mixture, marketed under the name Arlacel 165 by the company Croda.

Aqueous phase

The composition according to the invention comprises, in addition to the polyol, preferably a physiologically acceptable aqueous medium. By “physiologically acceptable”, is meant a medium compatible with keratin materials.

The composition according to the invention preferably comprises an aqueous medium comprising water and optionally an organic solvent soluble in water, at 25° C., chosen for example from linear or branched C2-C4 alkanols, such as as ethanol and isopropanol, propanol, butanol; and their mixtures.

The composition generally comprises from 10 to 99% by weight of water relative to the total weight of the composition, preferably from 20 to 90%.

The amount of organic solvent(s) can range, for example, from 0 to 30% by weight, preferably from 0.5 to 25% by weight, better still from 1 to 20% by weight, even better still from 1.5 to 15% by weight relative to the total weight of the composition.

Hydrophilic thickening polymer

Preferably, the composition of the invention comprises at least one hydrophilic thickening polymer.

The composition according to the invention may comprise at least one hydrophilic or water-soluble thickening polymer, chosen in particular from:

- natural polymers such as cellulose derivatives such as carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxymethylcellulose, hydroxypropylmethylcellulose, ethylhydroxyethylcellulose, xanthan gum, locust bean gum, scleroglucan, gellan, rhamsane gums, alginates, karaya gum, modified starches, modified or unmodified guar gums and their derivatives such as hydroxypropylguar, or hyaluronic acid salts such as sodium hyaluronate,

- hydrophilic clays. By hydrophilic clay is meant a clay capable of swelling in water; this clay swells in water and forms a colloidal dispersion after hydration. As hydrophilic clay, mention may be made of smectites such as saponites, hectorites, montmorillonites, bentonites, beidellite. Mention may be made of synthetic hectorites (also called laponites) such as the products sold by the company Laporte under the name Laponite XLG, Laponite RD, Laponite RDS (these products are sodium and magnesium silicates and in particular sodium silicates, lithium and magnesium); bentonites such as the product sold under the name Bentone HC by the company RHEOX; magnesium and aluminum silicates, in particular hydrated, such as the products sold by the company Vanderbilt Company under the name Veegum ultra, Veegum HS, Veegum DGT, or even calcium silicates and in particular that in synthetic form sold by the company under the name of Micro-cel C;

- homo- or copolymers of acrylic or methacrylic acids or their salts and their esters and in particular the products sold under the names VERSICOL F® or VERSICOL K® by the company ALLIED COLLOID, UTRAHOLD 8® by the company CIBA-GEIGY, or polyacrylic acids of the SYNTHALEN K type,

- copolymers of acrylic acid and acrylamide sold in the form of their sodium salt under the names RETEN® by the company HERCULES, the sodium salts of polyhydroxycarboxylic acids sold under the name HYDAGEN F® by the company HENKEL,

- poly(meth)acrylic acid/alkyl acrylate copolymers of the PEMULEN TR-1 or PEMULEN TR-2 type from BF Goodrich, or else Carbopol ETD-2020, Carbopol ETD-1382, Carbopol ETD-1342,

- homopolymers and copolymers based on acrylamido propanesulfonic acid (AMPS®, Lubrizol monomer), such as for example:

• polyacrylamidomethyl propane sulphonic acid partially neutralized with ammonia and highly crosslinked, marketed in particular by the company CLARIANT, for example under the name HOSTACERIN AMPS®;
• acrylamidomethyl propane sulfonic acid/acrylamide copolymers, for example of the SEPIGEL or SIMULGEL type marketed in particular by the company SEPPIC,
• copolymers of acrylamidomethyl propane sulfonic acid/polyoxyethylenated alkyl methacrylates (cross-linked or not) among others of the ARISTOFLEX HMS, ARISTOFLEX TAC type, marketed by the company CLARIANT,
• copolymers of acrylamidomethyl propane sulfonic acid and hydroxyethyl acrylate, such as for example the acrylamidomethyl propane sulfonic acid/hydroxyethyl acrylate copolymer such as in particular that used in the commercial product sold under the name SIMULGEL NS by the company SEPPIC, or else the copolymer acrylamidomethyl propane sulphonic acid/hydroxyethyl acrylate such as in particular that used in the commercial product sold under the name SEPINOV EMT 10 marketed by the company SEPPIC (INCI name: HYDROXYETHYL ACRYLATE/SODIUM ACRYLOYLDIMETHYL TAURATE COPOLYMER);

- associative polymers and in particular associative polyurethanes such as the C ₁₆ -OE ₁₂₀ -C ₁₆ polymer from the company ELEMENTIS (marketed under the name RHEOLATE FX1100, molecule with a urethane function and average molecular weight by weight of 1300), EO being an oxyethylenated unit, Rheolate 205 with a urea function sold by the company RHEOX or else Rheolate 208 or 204 (these polymers being sold in pure form) or DW 1206B from RHOM & HAAS with a C20 alkyl chain and urethane bond, sold at 20% active ingredient in water. It is also possible to use solutions or dispersions of these associative polyurethanes, in particular in water or in an aqueous-alcoholic medium. By way of example of such polymers, mention may be made of RHEOLATE FX1010, RHEOLATE FX1035 and RHEOLATE 1070, Rheolate 255, Rheolate 278 20 and Rheolate 244 sold by the company ELEMENTIS. You can also use the product DW 1206F and DW 1206J, as well as Acrysol RM 184 or Acrysol 44 from RHOM & HAAS, or even Borchigel LVV 44 from BORCHERS,

- and mixtures thereof.

Preferably, the hydrophilic thickening polymer, alone or as a mixture, is present in quantities of active material ranging from 0.01 to 20% by weight, more preferentially from 0.1 to 10% by weight, even more preferentially from 0, 1 to 5% by weight and more particularly from 0.1 to 3% by weight relative to the total weight of the composition.

Oil phase

The composition according to the invention also comprises at least one oil, in particular a cosmetic oil, forming an oily phase. It may also contain other fatty substances.

By “oil” is meant a non-aqueous compound, liquid at 25° C. and atmospheric pressure (1.013×10 ⁵ Pa), immiscible with water.

By "immiscible", it is meant that the mixture of the same quantity of water and oil, after stirring, does not lead to a stable solution comprising only a single phase, under the aforementioned temperature and pressure conditions. . The observation is made by eye or by means of a phase contrast microscope if necessary, on 100g of mixture obtained after Rayneri agitation sufficient to cause a vortex to appear within the mixture (as an indication 200 to 1000 rev /min); the resulting mixture being left to stand, in a closed flask, for 24 hours at room temperature before observation.

As oils that can be used in the composition of the invention, mention may be made, for example:

- hydrocarbon oils of animal origin, such as perhydrosqualene;

- hydrocarbon oils of vegetable origin, such as liquid triglycerides of fatty acids comprising from 4 to 10 carbon atoms such as triglycerides of heptanoic or octanoic acids or, for example, sunflower, corn, soybean oils, pumpkin, grape seed, sesame, hazelnut, apricot, macadamia, arara, sunflower, castor, avocado, caprylic/capric acid triglycerides such as those sold by the company Stearineries Dubois or those sold under the names Miglyol 810, 812 and 818 by Dynamit Nobel, jojoba oil, shea butter oil;

- synthetic esters and ethers, in particular of fatty acids, such as the oils of formulas R1COOR2 and R1OR2 in which R1 represents the residue of a fatty acid comprising from 8 to 29 carbon atoms, and R2 represents a hydrocarbon chain, branched or not, containing from 3 to 30 carbon atoms, such as, for example, Purcellin's oil, isononyl isononanoate, isopropyl myristate, ethyl-2-hexyl palmitate, octyl stearate -2-dodecyl, octyl-2-dodecyl erucate, isostearyl isostearate; hydroxylated esters such as isostearyl lactate, octylhydroxystearate, octyldodecyl hydroxystearate, diisostearylmalate, triisocetyl citrate, heptanoates, octanoates, decanoates of fatty alcohols; polyol esters, such as propylene glycol dioctanoate, neopentyl glycol diheptanoate and diethylene glycol diisononanoate; and pentaerythritol esters such as pentaerythrityl tetraisostearate or dipentaerythrityl pentaisononanoate;

- linear or branched hydrocarbons, of mineral or synthetic origin, such as paraffin oils, volatile or not, and their derivatives, branched chain hydrocarbon oils containing 10 to 20 carbon atoms such as isohexadecane, isododecane, isoparaffins and mixtures thereof, petroleum jelly, polydecenes, polyisobutenes, hydrogenated polyisobutenes such as, for example, Parléam® marketed by the company NIPPON OIL FATS, PANALANE H-300 E marketed by the company AMOCO, VISEAL 20000 marketed by SYNTEAL, REWOPAL PIB 1000 marketed by WITCO, or even PARLEAM LITE marketed by NOF Corporation;

- partially hydrocarbon and/or silicone fluorinated oils such as those described in document JP-A-2-295912;

- silicone oils such as volatile or non-volatile polymethylsiloxanes (PDMS) with a linear or cyclic silicone chain, liquid or pasty at room temperature, in particular cyclopolydimethylsiloxanes (cyclomethicones) such as cyclohexasiloxane; polydimethylsiloxanes comprising alkyl, alkoxy or phenyl groups, pendent or at the end of the silicone chain, groups having from 2 to 24 carbon atoms; phenyl silicones such as phenyltrimethicones, phenyldimethicones, phenyltrimethylsiloxydiphenylsiloxanes, diphenyl-dimethicones, diphenylmethyldiphenyl trisiloxanes, 2-phenylethyltrimethyl-siloxysilicates, and polymethylphenylsiloxanes; Or

- their mixtures.

As indicated above, the composition according to the invention may comprise, in the oily phase, other fatty substance(s). Preferably, this fatty substance is chosen from fatty alcohols having from 8 to 26 carbon atoms, such as cetyl alcohol, stearyl alcohol, the mixture of cetyl alcohol and stearyl alcohol (cetylstearyl alcohol), octyldodecanol, 2-butyloctanol, 2-hexyldecanol, 2-undecylpentadecanol, oleyl alcohol or linoleic alcohol.

The amount of oily phase can range for example from 0.1 to 30%, and for example from 5 to 25% by weight relative to the total weight of composition.

The composition according to the invention can also comprise any additive usually used in cosmetics, such as in particular fillers, preservatives, UV filters, coloring materials, and/or active agents.

As UV filter, mention may be made of organic or inorganic UV filters, well known to those skilled in the art.

As dyestuff, mention may be made of dyestuffs chosen from water-soluble dyes, pulverulent dyestuffs such as pigments, nacres, and flakes well known to those skilled in the art.

Among the preferred active agents, mention may in particular be made of retinol (vitamin A) and its derivatives including its esters such as retinyl palmitate, vitamin C, as well as C-glycoside derivatives.

The C-glycoside derivatives can be chosen from the compounds of the following general formula:

in which :

• R denotes an unsubstituted linear C ₁ -C ₄ , in particular C ₁ -C ₂ , in particular methyl radical;
• S represents a monosaccharide chosen from D-glucose, D-xylose, N-acetyl-D-glucosamine or L-fucose, and in particular D-xylose;
• X represents a group chosen from -CO-, -CH(OH)-, -CH(NH ₂ )-, and preferably a -CH(OH)- group;

as well as their cosmetically acceptable salts, their solvates such as hydrates and their optical isomers.

By way of non-limiting illustration of the C-glycoside derivatives more particularly suitable for the invention, mention may be made in particular of the following derivatives:

• C-beta-D-xylopyranoside-n-propane-2-one;
• C-alpha-D-xylopyranoside-n-propane-2-one;
• C-beta-D-xylopyranoside-2-hydroxy-propane;
• C-alpha-D-xylopyranoside-2-hydroxy-propane;
• 1-(C-beta-D-glucopyranosyl)-2-hydroxy-propane;
• 1-(C-alpha-D-glucopyranosyl)-2-hydroxy-propane;
• 1-(C-beta-D-glucopyranosyl)-2-amino-propane;
• 1-(C-alpha-D-glucopyranosyl)-2-amino-propane;
• 3'-(acetamido-C-beta-D-glucopyranosyl)-propane-2'-one;
• 3'-(acetamido-C-alpha-D-glucopyranosyl)-propan-2'-one;
• 1-(acetamido-C-beta-D-glucopyranosyl)-2-hydroxyl-propane;
• 1-(acetamido-C-beta-D-glucopyranosyl)-2-amino-propane;
• as well as their cosmetically acceptable salts, their solvates such as hydrates and their optical isomers.

According to a particular embodiment, C-beta-D-xylopyranoside-2-hydroxy-propane or C-alpha-D-xylopyranoside-2-hydroxy-propane, and better still C-beta-D-xylopyranoside-2- hydroxypropane, can advantageously be used for the preparation of a composition according to the invention.

According to a particular embodiment, a C-glycoside derivative suitable for the invention can advantageously be hydroxypropyl-tetrahydropyrantriol, also called C-beta-D-xylopyranoside-2-hydroxy-propane, in particular offered in solution at 30% by weight in a water/propylene glycol mixture (60/40) under the name MEXORYL SBB® by CHIMEX. The salts of the C-glycoside derivatives suitable for the invention can comprise conventional physiologically acceptable salts of these compounds, such as those formed from organic or inorganic acids. By way of example, mention may be made of the salts of mineral acids, such as sulfuric acid, hydrochloric acid, hydrobromic acid, hydriodic acid, phosphoric acid and boric acid. Mention may also be made of the salts of organic acids, which may contain one or more carboxylic, sulphonic or phosphonic acid groups. They may be linear, branched or cyclic aliphatic acids or alternatively aromatic acids. These acids may additionally comprise one or more heteroatoms chosen from O and N, for example in the form of hydroxyl groups. Mention may in particular be made of propionic acid, acetic acid, terephthalic acid, citric acid and tartaric acid. Acceptable solvates for the compounds described above include conventional solvates such as those formed during the last stage of preparation of said compounds due to the presence of solvents. By way of example, mention may be made of the solvates due to the presence of water or of linear or branched alcohols such as ethanol or isopropanol. A C-glycoside derivative suitable for the invention can in particular be obtained by the synthesis method described in document WO02/051828.

The composition according to the invention can be contained directly in a container, or indirectly. By way of example, the composition can be placed on any suitable support. In particular, this support is capable of absorbing the composition (impregnated support), such as for example a wipe; a fibrous, woven or non-woven make-up remover disk; felt ; wadding; a flocked film; or a sponge.

Preparation and properties

The cosmetic composition according to the present invention can be prepared by mixing the above essential and optional components according to a conventional method.

As indicated below, the composition according to the invention is an emulsion. Typically, it has a creamy appearance.

Thus, the composition according to the invention is not a “micro-emulsion” nor a “nano-emulsion”. A micro-emulsion refers to a single thermodynamically stable isotropic liquid phase containing a ternary system having three components comprising an oil component, an aqueous component and a surfactant. A micro-emulsion also refers to, among typical thermodynamically unstable emulsion systems, an emulsion exhibiting a transparent or translucent appearance due to small particle sizes. The composition according to the invention does not have a dispersed phase having a number average diameter of 300 nm or less, preferably 200 nm or less, and more preferably 100 nm or less, measured by laser granulometry or by optical microscopy.

On the contrary, the composition according to the invention is an emulsion which does not have a single thermodynamically stable isotropic liquid phase, and which is neither transparent nor translucent. It looks like cream, especially white cream. The dispersed phase typically contains droplets having a number-average diameter of the order of a micrometer, measured by laser granulometry or by optical microscopy.

By transparent or translucent composition (as is the case with micro-emulsions) outside the invention, is meant a composition having a turbidity value strictly less than 150 NTU.

Preferably, the turbidity of the compositions according to the invention is at least equal to 150 NTU.

NTU (nephelometric turbidity units) are the units of measurement of the turbidity of a composition. The measurement of the turbidity is carried out, for example, with a model 2100P turbidimeter from Hach Company, the tubes used for the measurement being referenced AR397A cat 24347-06. The measurements are carried out at room temperature (from 20°C to 25°C).

Finally, the invention also relates to a cosmetic process for caring for keratin materials, preferably the skin, comprising the application to said keratin materials of a composition according to the invention.

It also relates to the cosmetic use of a composition according to the invention for softening the skin, in particular the stratum corneum.

The softening effect of the skin gives the latter in particular a plumping effect and/or a plump appearance. The skin is smoother and has a fuller appearance, which is maintained even after pressure on the skin with the finger. This makes it possible to obtain surface effects, in particular on the cutaneous microreliefs, in particular to smooth wrinkles and fine lines; and/or moisturize the skin.

Concrete, but in no way limiting, examples illustrating the invention will now be given.

In the examples, the temperature is ambient (20° C.) and expressed in degrees Celsius unless otherwise indicated, and the pressure is atmospheric pressure, unless otherwise indicated.

In the examples, the amounts of the ingredients of the compositions are given in% by weight relative to the total weight of the composition.

Example 1: Preparation of e composition s according to the invention

The following compositions F1 and F2 according to the invention are prepared with the ingredients mentioned in the table below, according to the following protocol:

The ingredients of phase B are mixed and heated to 70°C;

The ingredients of phase A are mixed and heated to 70°C;

In an emulsifier, phase A is slowly poured into phase B;

At around 50° C., phase C is added and the gelling agents are allowed to unfold for about ten minutes. At around 40°C, pass under a Rayneri blade to add fillers (phase D). The temperature is allowed to drop with gentle stirring, then under 30° C. the ethanol (phase E) is added.

Ingredients Phase F1
(invention) F2
(invention) Water AT
Qsp 100
Qsp 100 Conservative AT Q's Q's Biosaccharide gum-2
(Rhamnosoft HP 1.5P from Solabia)
(2.5% active ingredient) AT 7.5 7.5 Glycerol AT 15 15 PG-2 oleate
(SUNSOFT Q-17D(G)-C by TAIYO KAGAKU) B 5 - PG-4 caprate
(TEGOSOFT PC 41 by EVONIK GOLDSCHMIDT) B - 5 GLYCERYL STEARATE (and) PEG-100 STEARATE
(Arlacel 165 from Croda) B 1 1 PEG-40 STEARATE
(Myrj 52 P from Croda) B 1 1 Ethanol E 3 3 SILICA MICROSPHERES
AMORPHOUS (5 µm) D 2.7 2.7 Isononyl isononanoate B 18.5 18.5 Dipentaerythrityl pentaisononanoate B 2.9 2.9 CELLULOSE BEADS
SPHERICAL (SIZE 4-
7µM) D 3 3 Sodium hyaluronate VS 0.2 0.2 HYDROXYETHYL ACRYLATE/SODIUM ACRYLOYLDIMETHYL TAURATE COPOLYMER
(Sepinov EMT 10 from Seppic) VS 0.36 0.36 AMMONIUM ACRYLOYLDIMETHYLTAURATE/STEARETH-25 METHACRYLATE CROSSPOLYMER
(Aristoflex HMS from Clariant) VS 0.7 0.7

Example 2: Measurement of the mechanical effect in vitro of a composition on the skin

The compositions can be tested for their mechanical properties of elasticity with respect to the stratum corneum, as follows:

A DMA (Dynamic Mechanical Analysis) device sold under the reference ElectroForce® 3100 by the company Bose is used.

This technique makes it possible to study the viscoelastic properties of the stratum corneum. The material is stressed sinusoidally and its deformation is measured. We can then determine the storage modulus (E') of the stratum corneum, which characterizes it mechanically. This magnitude is directly related to the elastic properties of the stratum corneum.

We can study the impact of a given formula on this conservation module.

Sample preparation and protocol:

The surface of the stratum corneum sample to be tested is 2 cm ² (1 cm X 2 cm). The samples are previously conditioned at 75% relative humidity for a minimum of 12 hours, and the measurement is also carried out at 75% relative humidity.

10 μl/cm ² of each formula to be tested are deposited on the stratum sample. Each formula is spread over the stratum corneum so as to cover the entire surface.

The dynamic stress amplitude was set at 40 µm, which corresponds to a deformation in the elastic domain of the stratum corneum (0.2% deformation). Each sample is solicited at the frequency of 1 Hz, along the longest length. Stratum corneum from at least two different donors is used.

For each formula, the variation of the elastic modulus measured with each sample treated, during the first two hours of treatment (E2h), is calculated with respect to that of the same untreated sample at t=0 (E0).

Then we get the results.

Example 3: Analysis live of one co Torquemeter® positioning on the skin

A prepared composition can be analyzed in vivo with the Torquemeter ^® as follows:

The Torquemeter is a non-invasive device. The DTM measuring head is made up of a mobile central disc 20 mm in diameter and a fixed circular plate. This device is affixed to the skin by means of a fixed concentric double-sided adhesive tape. The angle of rotation of the central disc is measured by a very high resolution angle sensor. When applying the measuring head, the central disc rotates. A torsional stress of an angle Ue is then applied to the skin zone between the mobile central disc and the peripheral fixed ring (rapid deformation). Then the angle of rotation continues to increase at reduced speed by an angle Uv.

After stopping the torque, the skin returns to its initial state in two stages, fast (Ur deformation) and slow to the origin.

The precise measurement areas are marked using a circular mask. The measured parameters are (Ue, Uv, Ur).

Then we get the results.

Claims (15)

Composition, preferably cosmetic, comprising, in a physiologically acceptable medium:
at least one polysaccharide comprising rhamnose,
at least one polyol,
at least one ester chosen from fatty acid esters comprising 10 carbon atoms and polyglycerol comprising 4 glycerol units, and fatty acid esters comprising 18 carbon atoms and polyglycerol comprising 2 glycerol units,
at least one oil, and
at least one surfactant which is a stearate comprising from 20 to 150 units of ethylene oxide. Composition according to Claim 1, characterized in that the polysaccharide comprises a rate of rhamnose ranging from 10% to 100% by weight relative to the total weight of the polysaccharide, preferably from 20% to 70% by weight, preferably from 40% at 60% by weight. Composition according to Claim 1 or 2, characterized in that the repetitive elements which constitute the polysaccharide comprise at least the components of general formula I:

wherein Rh is a rhamnose molecule, Rh* is a branched rhamnose molecule, O is a hexoside or pentoside sugar molecule, U is a uronic acid molecule and n is between 1 and 100, preferably between 5 and 65. Composition according to one of Claims 1 to 3, characterized in that the repetitive elements which constitute the polysaccharide consist of the sequence of general formula II:

in which Rh is a molecule of rhamnose, O is a molecule of a hexoside or pentoside sugar, U is a molecule of uronic acid and the ramification of the rhamnose on the ose O is done according to an osidic bond (1→2) or (1→3). Composition according to one of Claims 1 to 3, characterized in that the repetitive elements which constitute the polysaccharide consist of the sequence of general formula III:


in which Rh is a molecule of rhamnose, O is a molecule of a hexoside or pentoside sugar, U is a molecule of uronic acid and the ramification of the rhamnose on the rhamnose is done according to an osidic bond (1→3). Composition according to one of Claims 1 to 3, characterized in that the polysaccharide is a polymer of branched structure, of molecular weight of the order of 50,000 daltons, and having a saccharide sequence comprising three molecules of rhamnose (I, III , VI), two molecules of galactose (II, V) and one molecule of glucuronic acid (IV), said sequence having the following detailed formula:
Composition according to one of Claims 1 to 6, characterized in that the fatty acid ester comprising 10 carbon atoms and of polyglycerol comprising 4 glycerol units is polyglyceryl-4 caprate, and/or in that the The fatty acid ester comprising 18 carbon atoms and of polyglycerol comprising 2 glycerol units is polyglyceryl-2 oleate. Composition according to one of Claims 1 to 7, characterized in that the ester chosen from fatty acid esters comprising 10 carbon atoms and polyglycerol comprising 4 glycerol units and fatty acid esters comprising 18 carbon and polyglycerol comprising 2 glycerol units, is present in the composition in a content ranging from 0.5% to 10% by weight, relative to the total weight of the composition, preferably ranging from 1% to 7% by weight , and preferably ranging from 2% to 6% by weight. Composition according to one of Claims 1 to 8, characterized in that the polyol is chosen from glycerol and derivatives thereof, and glycols and derivatives thereof; preferably from glycerin, diglycerin, polyglycerin, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, pentylene glycol, hexylene glycol, 1,3-propanediol, 1,5-pentanediol , octane 1,2-diol, polyethylene glycols, in particular having from 5 to 50 ethylene oxide groups, and sugars such as sorbitol, and mixtures thereof. Composition according to one of Claims 1 to 9, characterized in that the polyol is present in a content ranging from 2% to 40% by weight, relative to the total weight of the composition, preferably ranging from 10% to 30% by weight, and preferably ranging from 10% to 15% by weight. Composition according to one of Claims 1 to 10, characterized in that the surfactant is a stearate comprising from 35 to 120 units of ethylene oxide, and preferably from 40 to 100 units of ethylene oxide. Composition according to one of Claims 1 to 11, characterized in that it comprises at least one additional surfactant chosen from C ₁₆ -C ₂₂ fatty acid and sorbitan esters and C ₁₆ fatty acid esters. -C ₂₂ and glyceryl, and/or at least one hydrophilic thickening polymer. Composition according to one of Claims 1 to 12, characterized in that it comprises at least one oil chosen from hydrocarbon oils of animal origin, hydrocarbon oils of vegetable origin, synthetic esters and ethers, in particular d fatty acids, linear or branched hydrocarbons, of mineral or synthetic origin, fluorinated partially hydrocarbon and/or silicone oils, silicone oils and mixtures thereof, and optionally at least one fatty substance preferably chosen from fatty alcohols having from 8 to 26 carbon atoms. Cosmetic process for caring for keratin materials, preferably the skin, comprising the application to said keratin materials of a composition according to one of Claims 1 to 13. Cosmetic use of a composition according to one of Claims 1 to 13 for softening the skin, in particular the stratum corneum.