WO2023004674A1

WO2023004674A1 - Composition for caring for skin

Info

Publication number: WO2023004674A1
Application number: PCT/CN2021/109215
Authority: WO
Inventors: Xiaomeng Wu; Xiaomin WENG
Original assignee: L'oreal
Priority date: 2021-07-29
Filing date: 2021-07-29
Publication date: 2023-02-02
Also published as: EP4376803A1; FR3125713A1; CN117813078A

Abstract

A composition comprises A) a natural polysaccharide having a molecular weight of 50,000-500,000; B) an emulsifier selected from amphoteric or anionic surfactant; and C) a wax. The composition can be used for caring for keratin materials, e.g., for skin, in particular for sensitive skin.

Description

COMPOSITION FOR CARING FOR SKIN

TECHNICAL FIELD

The present invention relates to a composition for caring for keratin material, especially for the skin. Further, the present invention relates to use of same, especially as an emulsion for caring for sensitive skin.

BACKGROUND

It has always been an ultimate goal of the cosmetic filed to deliver to the consumers’ highly efficient products with skin benefits such as hydration, moisturizing, whitening, cleansing, and so on.

For efficient delivery, various forms of products are utilized. Amongst others, emulsion is interested. For example, US 2014/0100276 discloses an emulsion composition which allows water to remain in the skin for a long period of time, wherein the emulsion presents a lamellar structure, which is, in particular in form of α-gel. Thanks to the lamellar structure, i.e., repeating bilayer structures, the cosmetic compositions are capable of providing to the skin a good retention of water, and therefore a long-lasting moistness. Various types of surfactants were used for stabilizing the α-gel structure and providing to the skin a water retention effect.

A lot of people have sensitive skins. For application on the sensitive skin, various technical solutions have been developed, most of which rely on selection of specific active agents to reduce the skin discomfort. Meanwhile, high content of active agents in formula may also lead potential risk for consumers with sensitive skin.

Based on the foregoing, there is a need for a new form of cosmetic composition to deliver desired ingredients to a sensitive skin.

SUMMARY OF THE INVENTION

The present inventors have discovered that a specific composition comprising specifically selected saccharide, emulsifier and a wax can form a liquid crystal emulsion, which is particularly useful for delivering actives to a sensitive skin.

Specifically, the composition according to the present invention comprises the components of:

A) a natural polysaccharide,

B) an emulsifier selected from amphoteric or anionic surfactant; and

C) a wax.

One subject of the invention is thus to provide a liquid crystal emulsion formed from the composition according to the present invention, e.g., by adding a solvent.

Another subject of the present invention is use of the composition according to the present invention for caring for keratin materials, especially the skin. This use may manifest itself as a process for caring for keratin materials, especially the skin, comprising the steps of compounding the composition at a predetermined weight ratio, and then applying to said keratin materials the thus obtained mixture.

Other characteristics and advantages of the present invention will emerge more clearly on reading the description and the examples that follow.

DESCRIPTION OF DRAWINGS

Fig. 1 shows the results according to Example 2; and

Fig. 2 shows the results according to Example 3.

DETAILED DESCRIPTION OF INVENTION

Throughout the description, including the claims, the term "comprising a" should be understood as being synonymous with "comprising at least one" , unless otherwise mentioned. Moreover, the expression "at least one" used in the present description is equivalent to the expression "one or more" .

Throughout the description, including the claims, an embodiment defined with “comprising” or the like should be understood to encompass a preferable embodiment defined with “consisting substantially of” and a preferable embodiment defined with “consisting of” .

Preferably, the “keratin material” according to the present invention is the skin. By “skin” , we intend all the body skin. For example, the keratin material may be the face or the neck.

In the application, unless specifically mentioned otherwise, contents, parts and percentages are expressed on a weight basis.

Other than in the operating examples, or where otherwise indicated, all numbers expressing quantities of components and/or reaction conditions are to be understood as being modified in all instances by the term "about" , with conventionally known meaning in the art, e.g., within 10%of the indicated number (such as "about 10%" means 9%-11 %and "about 2%" means 1.8%-2.2%) .

Component A) , Natural polysaccharide

Generally, natural polysaccharide means a polysaccharide obtainable from nature. For the purposes of the present invention, however, the term “natural polysaccharide” is intended to also encompass "polysaccharide of natural origin" , which denotes a polysaccharide obtained by modification of a polysaccharide obtainable from nature.

In general, natural polysaccharides that are suitable for use in the present invention may be homopolysaccharides such as fructans, glucans, galactans and mannans or heteropolysaccharides such as hemicellulose.

Similarly, they may be linear polysaccharides such as pullulan or branched polysaccharides such as gum arabic and amylopectin, or mixed polysaccharides such as starch.

In general, the polysaccharides may be chosen from ones produced by microorganisms; polysaccharides isolated from algae, and higher plant polysaccharides, such as homogeneous polysaccharides, in particular celluloses and derivatives thereof or fructosans, heterogeneous polysaccharides such as gum arables, galactomannans, glucomannans, and derivatives thereof; and mixtures thereof.

In particular, the polysaccharides may be chosen from fructans, gellans, glucans, amylose, amylopectin, glycogen, pullulan, dextrans, celluloses and derivatives thereof, such as methylcelluloses, hydroxyalkylcelluloses, ethylhydroxyethylcelluloses and carboxymethylcelluloses, mannans, xylans, lignins, arabans, galactans, galacturonans, chitin, chitosans, glucuronoxylans, arabinoxylans, xyloglucans, glucomannans, arabinogalactans, glycosaminoglucans, gum arables, tragacanth gums, ghatti gums, locust bean gums, galactomannans such as guar gums and nonionic derivatives thereof, in particular hydroxypropyl guar, and ionic derivatives thereof, biopoly saccharide gums of microbial origin, in particular sclerotium gum, e.g., scleroglucan, or xanthan gum, mucopolysaccharides, and in particular chondroitin sulfates, and mixtures thereof. These polysaccharides may be chemically modified, especially with urea or urethane groups or by hydrolysis, oxidation, esterification, etherification, sulfatation, phosphatation, amination, amidation or alkylation reaction, or by several of these modifications.

The derivatives obtained may be anionic, cationic, amphoteric or nonionic.

Advantageously, the polysaccharides may be chosen from xanthan gum, sclerotium gum, e.g., scleroglucan gum, guar gum, inulin and pullulan, and mixtures thereof.

More precisely, these polysaccharides that are suitable for use in the present invention may be distinguished according to whether they are derived from microorganisms, from algae or from higher plants, and are detailed below.

Polysaccharides produced by microorganisms

Xanthan

Xanthan is a heteropolysaccharide produced at the industrial scale by the aerobic fermentation of the bacterium Xanthomonas campestris. Its structure consists of a main chain of β (1, 4) -linked β-D-glucoses, similar to cellulose. One glucose molecule in two bears a trisaccharide side chain composed of an α-D-mannose, a β-D-glucuronic acid and a terminal β-D-mannose. The internal mannose residue is generally acetylated on carbon 6. About 30%of the terminal mannose residues bear a pyruvate group linked in chelated form between carbons 4 and 6. The charged pyruvic acids and glucuronic acids are ionizable, and are thus responsible for the anionic nature of xanthan (negative charge down to a pH equal to 1) . The content of pyruvate and acetate residues varies according to the bacterial strain, the fermentation process, the conditions after fermentation and the purification steps. These groups may be neutralized in commercial products with Na ⁺, K ⁺ or Ca ²⁺ ions (Satia company, 1986) . The neutralized form may be converted into the acid form by ion exchange or by dialysis of an acidic solution.

Xanthan gums have a molecular weight of between 1 000 000 and 50 000 000 and a viscosity of between 0.6 and 1.65 Pa. s for an aqueous composition containing 1%of xanthan gum (measured at 25℃ on a Brookfield viscometer of LVT type at 60 rpm) .

Xanthan gums are represented, for example, by the products sold under the names Rhodicare by the company Rhodia Chimie, under the name Satiaxane ^TM by the company Cargill Texturizing Solutions (for the food, cosmetic and pharmaceutical industries) , under the name Novaxan ^TM by the company ADM, and under the names

and

by the company CP-Kelco.

Pullulan

Pullulan is a polysaccharide consisting of maltotriose units, known under the name α (1, 4) -α (1, 6) -glucan. Three glucose units in maltotriose are connected via an α (1, 4) glycoside bond, whereas the consecutive maltotriose units are connected to each other via an α (1, 6) glycoside bond.

Pullulan is produced, for example, under the reference Pullulan PF 20 by the group Hayashibara in Japan.

Dextran and dextran sulfate

Dextran is a neutral polysaccharide not bearing any charged groups, which is biologically inert, prepared by fermentation of beet sugar containing solely hydroxyl groups. It is possible to obtain dextran fractions of different molecular weights from native dextran by hydrolysis and purification. Dextran may in particular be in the form of dextran sulfate.

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

Succinoglycan

Succinoglycan is an extracellular polymer of high molecular weight produced by bacterial fermentation, consisting of octasaccharide repeating units (repetition of 8 sugars) . Succinoglycans are sold, for example, under the name Rheozan by the company Rhodia.

Scleroglucan

Scleroglucan is a nonionic branched homopolysaccharide consisting of β-D-glucan units. The molecules consist of a linear main chain formed from D-glucose units linked via β (1, 3) bonds and of which one in three is linked to a side D-glucose unit via a β (1, 6) bond.

A more complete description of scleroglucans and of their preparation may be found in patent US 3 301 848.

Scleroglucan is sold, for example, under the name Amigel by the company Alban Miiller, or under the name Actigum ^TM CS by the company Cargill.

Polysaccharides isolated from algae

Furcellaran

Furcellaran is obtained commercially from red algae Furcellaria fasztigiata. Furcellaran is produced, for example, by the company Est-Agar.

Polysaccharides from plants

This category of polysaccharides may be divided into homogeneous polysaccharides (only one saccharide species) and heterogeneous polysaccharides composed of several types of saccharides.

a) Homogeneous polysaccharides and derivatives thereof

The polysaccharide according to the present invention may be chosen from celluloses and derivatives or fructosans.

Cellulose and derivatives

The polysaccharide according to the present invention may also be a cellulose or a derivative thereof, especially cellulose ethers or esters (e.g. methylcellulose, carboxymethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxymethylpropylcellulose, cellulose acetate, cellulose nitrate, nitrocellulose) .

The present invention may also contain a cellulose-based associative polymer.

According to the present invention, the term "cellulose-based compound" means any polysaccharide compound bearing in its structure linear sequences of anhydroglucopyranose residues (AGU) linked together via β (1, 4) bonds. The repeating unit is the cellobiose dimer. The AGUs are in chair conformation and bear 3 hydroxyl functions: 2 secondary alcohols (in position 2 and 3) and a primary alcohol (in position 6) . The polymers thus formed combine together via intermolecular bonds of hydrogen bond type, thus giving the cellulose a fibrillar structure (about 1500 molecules per fibre) .

The degree of polymerization differs enormously depending on the origin of the cellulose; its value may range from a few hundred to several tens of thousands.

The hydroxyl groups of cellulose may react partially or totally with various chemical reagents to give cellulose derivatives having intrinsic properties. The cellulose derivatives may be anionic, cationic, amphoteric or nonionic. Among these derivatives, cellulose ethers, cellulose esters and cellulose ester ethers are distinguished.

Among the nonionic cellulose ethers, mention may be made of alkylcelluloses such as methylcelluloses and ethylcelluloses; hydroxyalkylcelluloses such as hydroxymethylcelluloses, hydroxyethylcelluloses and hydroxypropylcelluloses; and mixed hydroxyalkylalkylcelluloses such as hydroxypropylmethylcelluloses, hydroxy-ethylmethylcelluloses, hydroxy ethylethylcelluloses and hydroxybutylmethylcelluloses.

Among the anionic cellulose ethers, mention may be made of carboxyalkylcelluloses and salts thereof. By way of example, mention may be made of carboxymethylcelluloses, carboxymethylmethylcelluloses and carboxymethylhydroxy-ethylcelluloses and sodium salts thereof.

Among the cationic cellulose ethers, mention may be made of crosslinked or non-crosslinked, quaternized hydroxyethylcelluloses.

The quaternizing agent may in particular be glycidyltrimethylammonium chloride or a fatty amine such as laurylamine or stearylamine. Another cationic cellulose ether that may be mentioned is hydroxy ethylcellulosehydroxypropyltrimethylammonium.

The quaternized cellulose derivatives are, in particular:

- quaternized celluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyl or alkylaryl groups comprising at least 8 carbon atoms, or mixtures thereof,

- quaternized hydroxyethylcelluloses modified with groups comprising at least one fatty chain, such as alkyl, arylalkyl or alkylaryl groups comprising at least 8 carbon atoms, or mixtures thereof.

The alkyl radicals borne by the above quaternized celluloses or hydroxyethylcelluloses preferably contain from 8 to 30 carbon atoms. The aryl radicals preferably denote phenyl, benzyl, naphthyl or anthryl groups.

Examples of quaternized alkylhydroxyethylcelluloses containing C _8-30 fatty chains that may be indicated include the products Quatrisoft LM 200, Quatrisoft LM-X 529-18-A, Quatrisoft LM-X 529-18B (C ₁₂ alkyl) and Quatrisoft LM-X 529-8 (C ₁₈ alkyl) sold by the company Amerchol and the products Crodacel QM, Crodacel QL (C ₁₂ alkyl) and Crodacel QS (C ₁₈ alkyl) sold by the company Croda.

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

- celluloses modified with groups comprising at least one fatty chain, for instance hydroxyethylcelluloses modified with groups comprising at least one fatty chain, such as alkyl groups, especially of C _8-22, arylalkyl and alkylaryl groups, such as Natrosol Plus Grade 330 CS (C ₁₆ alkyls) sold by the company Aqualon, and

- celluloses modified with polyalkylene glycol alkylphenyl ether groups, such as the product Amercell Polymer HM-1500 (nonylphenyl polyethylene glycol (15) ether) sold by the company Amerchol.

Among the cellulose esters are mineral esters of cellulose (cellulose nitrates, sulfates, phosphates, etc. ) , organic cellulose esters (cellulose monoacetates, triacetates, amidopropionates, acetatebutyrates, acetatepropionates and acetatetrimellitates, etc. ) , and mixed organic/mineral esters of cellulose, such as cellulose acetatebutyrate sulfates and cellulose acetatepropionate sulfates. Among the cellulose ester ethers, mention may be made of hydroxypropylmethylcellulose phthalates and ethylcellulose sulfates.

The cellulose-based compounds of the present invention may be chosen from unsubstituted celluloses and substituted celluloses. The celluloses and derivatives are represented, for example, by the products sold under the names

(microcrystalline cellulose, MCC) by the company FMC Biopolymers, under the name Cekol (carboxymethylcellulose) by the company Noviant (CP-Kelco) , under the name Akucell AF(sodium carboxymethylcellulose) by the company Akzo Nobel, under the name Methocel ^TM (cellulose ethers) and Ethocel ^TM (ethylcellulose) by the company Dow, and under the names

(carboxymethylcellulose and sodium carboxymethylcellulose) ,

(methylcellulose) , Blanose ^TM (carboxymethylcellulose) ,

(methylcellulose, hydroxypropylmethylcellulose) ,

(hydroxypropylcellulose) ,

(cetylhydroxyethylcellulose) and

CS (hydroxy ethylcellulose) by the company Hercules Aqualon.

Fructosans

The polysaccharide according to the present invention may especially be a fructosan chosen from inulin and derivatives thereof (especially dicarboxy and carboxymethyl inulins) .

Fructans or fructosans are oligosaccharides or polysaccharides comprising a sequence of anhydrofructose units optionally combined with several saccharide residues other than fructose. Fructans may be linear or branched. Fructans may be products obtained directly from a plant or microbial source or alternatively products whose chain length has been modified (increased or decreased) by fractionation, synthesis or hydrolysis, in particular enzymatic. Fructans generally have a degree of polymerization from 2 to about 1000 and preferably from 2 to about 60.

Three groups of fructans are distinguished. The first group corresponds to products whose fructose units are for the most part linked via β (2, 1) bonds. These are essentially linear fructans such as inulins.

The second group also corresponds to linear fructoses, but the fructose units are essentially linked via β (2, 6) bonds. These products are levans.

The third group corresponds to mixed fructans, i.e. containing β (2, 6) and β (2, 1) sequences. These are essentially branched fructans, such as graminans.

The preferred fructans in the compositions according to the present invention are inulins. Inulin may be obtained, for example, from chicory, dahlia or Jerusalem artichoke, preferably from chicory.

In particular, the polysaccharide, especially the inulin, has a degree of polymerization from 2 to about 1000 and preferably from 2 to about 60, and a degree of substitution of less than 2 on the basis of one fructose unit.

The inulin used for the present invention is represented, for example, by the products sold under the name Beneo ^TM inulin by the company Orafti, and under the name

by the company Sensus.

b) Heterogeneous polysaccharides and derivatives thereof

The polysaccharides that may be used according to the present invention may be gums, for instance cassia gum, karaya gum, konjac gum, gum tragacanth, tara gum, acacia gum or gum arabic.

Gum arabic

Gum arabic is a highly branched acidic polysaccharide which is in the form of mixtures of potassium, magnesium and calcium salts. The monomer elements of the free acid (arabic acid) are D-galactose, L-arabinose, L-rhamnose and D-glucuronic acid.

Galactomannans (guar, locust bean, fenugreek, tara gum) and derivatives (guar phosphate, hydroxypropyl guar, etc. )

Galactomannans are nonionic polyosides extracted from the endosperm of leguminous seeds, of which they constitute the storage carbohydrate.

Galactomannans are macromolecules consisting of a main chain of β (1, 4) -linked D-mannopyranose units, bearing side branches consisting of a single D-galactopyranose unit α (1, 6) -linked to the main chain. The various galactomannans differ, firstly, by the proportion of α-D-galactopyranose units present in the polymer, and secondly, by significant differences in terms of distribution of galactose units along the mannose chain.

The mannose/galactose (M/G) ratio is about 2 for guar gum, 3 for tara gum and 4 for locust bean gum.

Guar

Guar gum is characterized by a mannose/galactose ratio of the order of 2/1. The galactose group is regularly distributed along the mannose chain.

The guar gums that may be used according to the present invention may be nonionic, cationic or anionic. According to the present invention, use may be made of chemically modified or unmodified nonionic guar gums.

The unmodified nonionic guar gums are, for example, the products sold under the names Vidogum GH, Vidogum G and Vidocrem by the company Unipektin and under the name Jaguar by the company Rhodia, under the name

Guar by the company Danisco, under the name Viscogum ^TM by the company Cargill, and under the name

guar gum by the company Aqualon.

The hydrolysed nonionic guar gums that may be used according to the present invention are represented, for example, by the products sold under the name

by the company Danisco.

The modified nonionic guar gums that may be used according to the present invention are preferably modified with C _1-6 hydroxyalkyl groups, among which mention may be made, for example, of hydroxymethyl, hydroxyethyl, hydroxypropyl and hydroxybutyl groups.

Such nonionic guar gums optionally modified with hydroxyalkyl groups are sold, for example, under the trade names Jaguar HP 60, Jaguar HP 105 and Jaguar HP 120 (hydroxypropyl guar) by the company Rhodia or under the name

HP (hydroxypropyl guar) by the company Aqualon.

The cationic galactomannan gums preferably have a cationic charge density of less than or equal to 1.5 meq. /g, more particularly between 0.1 and 1 meq. /g. The charge density may be determined by the Kjeldahl method. It generally corresponds to a pH of the order of 3 to 9.

In general, for the purposes of the present invention, the term "cationic galactomannan gum" means any galactomannan gum containing cationic groups and/or groups that can be ionized into cationic groups.

The preferred cationic groups are chosen from those comprising primary, secondary, tertiary and/or quaternary amine groups.

The cationic galactomannan gums used generally have a weight-average molecular mass of between 500 and 5×10 ⁶ approximately and preferably between 10 ³ and 3×10 ⁶ approximately.

The cationic galactomannan gums that may be used according to the present invention are, for example, gums comprising tri (C _1-4) alkylammonium cationic groups. Preferably, 2%to 30%by number of the hydroxyl functions of these gums bear trialkylammonium cationic groups.

Among these trialkylammonium groups, mention may be made most particularly of trimethylammonium and triethylammonium groups.

Even more preferentially, these groups represent from 5%to 20%by weight relative to the total weight of the modified galactomannan gum.

According to the present invention, the cationic galactomannan gum is preferably a guar gum comprising hydroxypropyltrimethylammonium groups, i.e. a guar gum modified, for example, with 2, 3-epoxypropyltrimethylammonium chloride.

These galactomannan gums, in particular guar gums modified with cationic groups are products already known per se and are, for example, described in patents US 3 589 578 and US 4 031 307. Such products are moreover sold especially under the trade names Jaguar EXCEL, Jaguar C13 S, Jaguar C 15, Jaguar C 17 and Jaguar CI 62 (Guar Hydroxypropyltrimonium Chloride) by the company Rhodia, under the name

Guar (Guar Hydroxypropyltrimonium Chloride) by the company Degussa, and under the name

3000 (Guar Hydroxypropyltrimonium Chloride) by the company Aqualon.

The anionic guar gums that may be used according to the present invention are polymers comprising groups derived from carboxylic, sulfonic, sulfenic, phosphoric, phosphonic or pyruvic acid. The anionic group is preferably a carboxylic acid group. The anionic group may also be in the form of an acid salt, especially a sodium, calcium, lithium or potassium salt.

The anionic guar gums that may be used according to the present invention are preferentially carboxymethyl guar derivatives (carboxymethyl guar or carboxymethyl hydroxypropyl guar) .

Locust bean

Locust bean gum is extracted from the seeds of the locust bean tree Ceratonia siliqua) .

The unmodified locust bean gum that may be used in the present invention is sold, for example, under the name Viscogum ^TM by the company Cargill, under the name Vidogum L by the company Unipektin and under the name

LBG by the company Danisco.

The chemically modified locust bean gums that may be used in the present invention may be represented, for example, by the cationic locust beans sold under the name Catinal CLB (locust bean hydroxypropyltrimonium chloride) by the company Toho.

Tara gum

The tara gum that may be used in the context of the present invention is sold, for example, under the name Vidogum SP by the company Unipektin.

Other polysaccharides

Among the other polysaccharides that may be used according to the present invention, mention may also be made of chitin (poly-N-acetyl-D-glucosamine, β (1, 4) -2-acetamido-2-deoxy-D-glucose) , chitosan and derivatives (chitosan-β-glycerophosphate, carboxymethylchitin, etc. ) such as those sold by the company France-Chitine; glycosaminoglycans (GAG) such as hyaluronic acid, chondroitin sulfate, dermatan sulfate, keratan sulfate, and preferably hyaluronic acid; xylans (or arabinoxylans) and derivatives.

Arabinoxylans are polymers of xylose and arabinose, all grouped under the name pentosans. Xylans consist of a main chain of β (1, 4) -linked D-xylose units and on which are found three substituents (Rouau&Thibault, 1987) : acid units, α-L-arabinofuranose units, side chains which may contain arabinose, xylose, galactose and glucuronic acid.

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

Carrageenans are composed essentially of potassium, sodium, magnesium, triethanolamine and/or calcium salts of polysaccharide sulfate esters.

Carrageenans are sold especially by the company SEPPIC under the name

by the company Gelymar under the names

and

by the company Cargill, under the names Satiagel ^TM and Satiagum ^TM, and by the company CP-Kelco under the names

and

Agars are galactose polysaccharides contained in the cell wall of some of these species of red algae (rhodophyceae) . They are formed from a polymer group whose base backbone is a β (1, 3) D-galactopyranose and α (1, 4) L 3-6 anhydrogalactose chain, these units repeating regularly and alternately. The differences within the agar family are due to the presence or absence of solvated methyl or carboxyethyl groups. These hybrid structures are generally present in variable percentage, depending on the species of algae and the harvest season.

Agar-agar is a mixture of polysaccharides (agarose and agaropectin) of high molecular mass, between 40000 and 300000 g. mol ^-1. It is obtained by manufacturing algal extraction liquors, generally by autoclaving, and by treating these liquors which comprise about 2%of agar-agar, so as to extract the latter.

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

Gellan gum is an anionic linear heteropolyoside based on oligoside units composed of 4 saccharides (tetra-oside) . D-Glucose, L-rhamnose and D-glucuronic acid in 2: 1: 1 proportions are present in gellan gum in the form of monomer elements.

According to the present invention, although various natural polysaccharides can be used, it is preferred to sue a natural polysaccharide having a relatively lower or medium molecular weight. For example, among the natural polysaccharides above, the preferred one has a molecular weight of 5,000-500,000, preferably 10,000-200,000, or preferably 30,000-100,000.

The natural saccharide may be present in an amount ranging for example from 0.1 to 10%by weight, preferably 0.1 to 5%by weight and more preferably from 0.2 to 1%by weight relative to the total weight of the composition.

Component B) , emulsifier

One subject of the invention is thus to provide a liquid crystal emulsion formed from the composition according to the present invention. The composition according to the present invention can preferably in a form of an oil-in-water (O/W) emulsion. Accordingly, the composition preferably comprises an emulsifier selected from amphoteric or anionic surfactant.

Amphoteric surfactant

For the purposes of the present invention, the term “amphoteric surfactant” is intended to encompass those surfactants conventionally called as both "amphoteric surfactant" and “zwitterionic surfactant” .

The amphoteric surfactants may for example be selected from (C8-C20) alkylbetaines, sulfobetaines (also called sultaines) , (C8-C20) alkylsulfobetaines, (C8-C20) alkylamido (C1-C6) alkylbetaines, such as cocamidopropylbetaine, and (C8-C20) alkylamido (C1-C6) alkylsulfobetaines, amino acids such as glycine, (C8-C20) alkyl polyaminocarboxylates, (C8-C20) alkylamphoacetates, (C8-C20) alkylamphodiacetates, lecithins, salts thereof, derivatives thereof and mixtures thereof.

As (C8-C20) alkylbetaines, mention may notably be made of cocobetain like the product marketed under the name of DEHYTON

by Cognis, laurylbetain like the product marketed under the name of GENAGEN

by Clariant, oxyethylene laurylbetain (10 EO) , like the product marketed under the name of LAURYLETHER (10 EO)

by Shin Nihon Rica, oxyethylene stearylbetain (10 EO) like the product marketed under the name of STEARYLETHER (10 EO)

by Shin Nihon Rica.

Among the (C8-C20) alkylamido (C1-C6) alkylbetaines, mention may for example be made of cocamidopropyl betaine like the products marketed under the name of LEBON 2000

by Sanyo, under the name of EMPIGEN

by Albright&Wilson, under the names of Tego Betain F 50 and CK D by EVONIK GOLDSCHMIDT, or further those marketed as a mixture with glyceryl laurate like the commercial references Tego Betain HS or Antil HS 60 from EVONIK GOLDSCHMIDT, lauramidopropyl betaine like the product marketed under the name of REWOTERIC

by Witco. In a particular embodiment, (C8-C20) alkylamido (C1-C6) alkylbetaines are preferably chosen among (C8-C20) alkylamidopropylbetaines.

As sultains, mention may be made of (C8-C20) alkylsulfobetaines; alkyl (C8-C20) amidoalkyl (C1-C6) sulfobetaines, alkyl (C8-C20) amidoalkyl (C1-C6) hydroxyl sulfobetaines such as cocoyl-amidopropylhydroxy-sulfobetaine such as the one marketed under the name of CROSULTAIN

by Croda.

As (C8-C20) alkyl polyaminocarboxylates (APAC) , mention may be made of sodium cocoylpolyamino-carboxylate, such as the one marketed under the name of AMPHOLAK 7

and AMPHOLAK 7

by AkzoNobel, sodium stearyl-polyamidocarboxylate such as the one marketed under the name of AMPHOLAK 7 TX/C by AkzoNobel, sodium carboxymethyloleyl-polypropylamine, such as the one marketed under the name of AMPHOLAK

by AkzoNobel. As C8-C20 alkyldiamphoacetates, mention may for example be made of N-di-sodium N-cocoyl-N-carboxymethoxyethyl-N-carboxymethyl-ethylenediamine (CTFA name: disodium cocamphodiacetate) like the product marketed under the name of MIRANOL C2M CONCENTRE

by Rhodia Chimie, and N-sodium N-cocoyl-N-hydroxyethyl-N-carboxymethyl-ethylenediamine (CTFA name: sodium cocamphoacetate) like the one sold by Evonik Goldschmidt under the name Rewoteric AM C.

As C8-C20 alkylamphodiacetates, mention may be made of disodium cocoamphodiacetate, disodium lauroamphodiacetate, disodium caproamphodiacetate, disodium capryloamphodiacetate, disodium cocoamphodipropionate, disodium lauroamphodipropionate, disodium caproamphodipropionate, disodium capryloamphodipropionate, lauroamphodipropionic acid and cocoampho-idipropionic acid. Examples that may be mentioned include the cocoamphodiacetate sold by the company Rhodia under the trade name

C2M Concentrate.

Among lecithins, mention may be made of phospholipids and lysophospholipids. In particular, mention may be made of lecithins such as the product marketed by the NIKKOL group (Lecinol Series) or further lecithins marketed by CARGIL/LUCAS MEYER (the family of EMULMETIKS of EMULFLUIDS) .

In particular, a derivative of lecithin can be preferably used. Amongst others, hydrogenated lecithin can be used advantageously.

Anionic surfactant

The term “anionic surfactant” is understood to mean an amphiphilic compound with a hydrophobic part and a hydrophilic part wherein the hydrophilic part carries as ionic or ionisable group only anionic group with a cationic counterion which is generally metallic (alkali metal, such as Na or K) or ammonium, capable of dissociating to give anions in aqueous solution.

More particularly the anionic group of the anionic surfactant is belonging to the group chosen from: C (O) OH, –C (O) O ^-, -SO ₃H, -S (O) ₂O ^-, -OS (O) ₂OH, -OS (O) ₂O ^-, -P (O) OH ₂, -P (O) ₂O ^-, -P (O) O ₂ ^-, -P (OH) ₂, =P (O) OH, -P (OH) O ^-, =P (O) O ^-, =POH, =PO ^-, the cationic counter being usually selected from alkali metal such as sodium, or alkaline earth metal such as magnesium, or organic cationic counter anion such as ammonium salts, amine salts, or aminoalcohol salts.

Mention may be made, as anionic surfactants, of surfactants comprising carboxylate, sulfate, sulfonate, sulfoacetate, sulfosuccinate, phosphate, isethionate, sarcosinate, glutamate, lactylate or taurate anionic groups, salts of fatty acids, salts of galactosiduronic acids, salts of ether carboxylic acids surfactants and their mixtures.

More particularly, the anionic surfactant according to the invention is chosen from:

● (C ₆-C ₃₀) alkyl sulfates, (C ₆-C ₃₀) alkyl ether sulfates, (C ₆-C ₃₀) alkylamido ether sulfates, alkylaryl polyether sulfates or monoglyceride sulfates; preferably for this type of anionic surfactants, (C ₆-C ₃₀) alkyl ether sulfates, alkylaryl polyether sulfates, or a mixture is used. Mentions may be made of sulfate of ether of lauryl alcohol and alkylene oxide, containing from 1 to 50 alkylene oxide groups.

● (C ₆-C ₃₀) alkyl sulfonates, (C ₆-C ₃₀) alkylamidesulfonates, (C ₆-C ₃₀) alkylaryl sulfonates, α-olefin sulfonates, paraffin sulfonates;

● (C ₆-C ₃₀) akyl phosphates;

● (C ₆-C ₃₀) alkyl sulfosuccinates, (C ₆-C ₃₀) alkyl ether sulfosuccinates or (C ₆-C ₃₀) alkylamido sulfosuccinates;

● (C ₆-C ₃₀) alkyl sulfoacetates;

● (C ₆-C ₂₄) acylsarcosinates;

● (C ₆-C ₂₄) acylglutamates;

● (C ₆-C ₃₀) alkylpolyglycoside carboxylic ethers;

● (C ₆-C ₃₀) alkylpolyglycoside sulfosuccinates;

● (C ₆-C ₃₀) alkyl sulfosuccinamates;

● (C ₆-C ₂₄) acyl isethionates, for example sodium lauroyl methyl isethionate, sodium cocoyl isthionate; mentiones may be made of the sodium lauroyl methyl isethionate which is sold under the trade name

LQ-CLR-SB by the company Innospec Active Chemicals;

● N- [ (C ₆-C ₂₄) acyl] taurates;

● salts of fatty acids;

● (C ₈-C ₂₀) acyl lactylates;

● salts of (C ₆-C ₃₀) alkyl-D-galactosiduronic acids;

● salts of (C ₆-C ₃₀) alkyl polyoxyalkylenated ether carboxylic acids, of (C ₆-C ₃₀) alkylaryl polyoxyalkylenated ether carboxylic acids or of (C ₆-C ₃₀) alkylamido polyoxyalkylenated ether carboxylic acids;

● and their mixtures.

The alkyl or acyl radicals of these various anionic surfactants preferably comprise from 12 to 20 carbon atoms.

Furthermore, the oxyalkylenated or polyoxyalkylenated anionic surfactants preferably comprise from 1 to 50 alkylene oxide groups, more preferably from 1 to 4 alkylene oxide groups, in particular ethylene oxide groups.

According to a particular embodiment of the invention, the anionic surfactant (s) may comprise at least one sulfonate function, acyl glutamates, and mixtures thereof, including, for example, at least one C16-C22 hydrocarbon-based chain.

According to a preferred embodiment of the invention, the anionic surfactant (s) comprising at least one sulfonate function are chosen from (C16-C22) alkylsulfonates, (C16-C22) alkylamidesulfonates, (C16-C22) alkylarylsulfonates, (C16-C22) alkylsulfoacetates, N-acyl (C16-C22) -N- (C1-C6) alkyltaurates, (C16-C22) acylisethionates, (C16-C22) alkylsulfolaurates, and mixtures thereof.

Preferentially, the anionic surfactant (s) comprising at least one sulfonate function are chosen from:

- acylisethionates, the linear or branched acyl group comprising from 16 to 22 carbon atoms, preferably from 16 to 18 carbon atoms;

- N-acyl-N-alkyltaurates, the linear or branched acyl group comprising from 16 to 22 carbon atoms, preferably from 16 to 18 carbon atoms, and the linear or branched alkyl group comprising from 1 to 6 carbon atoms, or cyclic group comprising from 3 to 6 carbon atoms; preferably, the alkyl group is a methyl,

- and mixtures thereof.

According to an especially exemplary embodiment of the present invention, the composition may be free of any sulfate to be used as the anionic surfactant. For example, the anionic surfactant may be a taurate, e.g., sodium methyl stearoyl taurate.

N-acyl-N-alkyltaurates can be also preferred, for which mention may be made of sodium palmitoyl methyltaurate sold under the name Nikkol

by the company Nikkol; the sodium salt of N-stearoyl N-methyl taurate sold under the name Nikkol SMT by the company Nikko.

According to a preferred embodiment of the invention, the acyl glutamate (s) are chosen from acyl glutamates in which the acyl group comprises from 16 to 18 carbon atoms.

Examples of acyl glutamates that may notably be mentioned include palmitoyl glutamic acid, stearoyl glutamic acid, behenoyl glutamic acid, olivoyl glutamic acid, and the salts of these acids, notably the alkali metal salts such as the Na, Li or K and preferably Na or K salts, the alkaline-earth metal salts such as the Mg salts or the ammonium salts of said acids.

Mention may be made, for example, of the compounds having the INCI name sodium stearoyl glutamate, sodium olivoyl glutamate, and mixtures thereof.

As acylglutamic acid salts, mention may also be made of sodium stearoyl glutamate, such as the product sold under the reference Acylglutamate HS 11 by the company Ajinomoto and disodium hydrogenated stearoyl glutamate, such as the product sold under the reference Acylglutamate HS-21 by the company Ajinomoto.

According an embodiment of the present invention, it is believed, without being limited by any known theory, that the concurrent use of an amphoteric surfactant and an anionic surfactant may be particularly advantageous. In particular, the concurrent use thereof may be specially beneficial for the stability, as well as the heat-resistance, of the composition formulated. Further this additionally advantageous purpose, the amphoteric surfactant and the anionic surfactant can be used at a ratio by weight of 2: 8 to 8: 2, preferably 4: 6 to 6: 4.

The emulsifier may be present in an amount ranging for example from 0.1 to 3%by weight, preferably 0.2 to 3%by weight and more preferably from 0.2 to 1%by weight relative to the total weight of the composition.

Solvent

The composition according to the invention comprises at least one solvent. In particular, for example, the composition according to the present invention can be provided in a form of an oil-in-water (O/W) emulsion, comprising an oil phase and an aqueous phase.

Preferably, the component A) , i.e., the natural polysaccharide, and the component B) , i.e., the emulsifier, are both introduced into the aqueous phase.

The aqueous phase may comprise water and hydrophilic adjuvants (co-solvents, actives and additives) . The water preferably represents at least 50%by weight of the total weight of the composition. In a particular embodiment, the composition according to the invention comprises water in a content ranging from 55%to 95%by weight relative to the total weight of the composition, preferably ranging from 70%to 90%by weight. and preferably ranging from 50%to 90%by weight.

The water used may be sterile demineralized water and/or a floral water such as rose water, cornflower water, camomile water or lime blossom water, and/or a natural spring water or mineral water, for instance: Vittel water, Vichy basin water, Uriage water, Roche Posay water, Bourboule water, Enghien-les-Bains water, Saint Gervais-les-Bains water, Néris-les-Bains water, Allevar-les-Bains water, Digne water, Maizières water, Neyrac-les-Bains water, Lons-le-Saunier water, Eaux Bonnes water, Rochefort water, Saint Christau water, Fumades water, Tercis-les-bains water and Avene water. The aqueous phase may also comprise reconstituted spring water, i.e. a water compriseing trace elements such as zinc, copper, magnesium, etc., reconstituting the characteristics of a spring water.

Preferably, the aqueous phase comprises at least one organic solvent miscible with water (at room temperature 25℃) such as for example monoalcohols having from 2 to 6 carbon atoms such as ethanol, isopropanol; polyols notably having from 2 to 20 carbon atoms, preferably from 2 to 10 carbon atoms, and preferentially having from 2 to 6 carbon atoms, such as glycerine, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, caprylyl glycol, dipropylene glycol, diethylene glycol; glycol ethers (having in particular from 3 to 16 carbon atoms) such as the mono, di or tripropylene glycol (C1-C4) alkyl ethers, the mono, di or triethylene glycol (C1-C4) alkyl ethers; and mixtures thereof.

In a particular embodiment of the invention, the water-miscible polyol at room temperature is present in a content ranging from 1%to 15%by weight, and preferably ranging from 2%to 10%by weight, relative to the total weight of the composition.

Preservative

For use of the present invention, the composition according to the present invention may comprise at least on preservative. Preferably, the preservative can be present in the aqueous phase. The preservative useful according to the present invention can be any one conventionally used for cosmetics, in particular for masks.

For example, preservatives can be used according to the present invention comprise methylchloroisothiazolinone, imidazolidinyl urea, derivatives of hydantoin, such as DMDMH, parahydroxybenzoate ester, phenoxyethanol, benzyl alcohol, chlorphenesin, benzoic acid and a salt thereof, such as sodium benzoate, potassium sorbate, hydroxyacetophenone, amino-acid based preservative, sorbitan octanate, glycerol caprylate and the like.

Preferably, the content of the preservative is 0.01-5%, preferably 0.1%-3%, preferably 0.3%-1%, based on the weight of the composition.

Component C) , wax

The composition according to the present invention can comprise a wax as component C) .

The wax under consideration in the context of the present invention is generally a lipophilic compound that is solid at room temperature (25℃) , with a solid/liquid reversible change of state, having a melting point of greater than or equal to 30℃, preferably greater than or equal to 40℃, which may be up to 200℃ and in particular up to 120℃.

Amongst others, the wax in the composition according to the present invention preferably has a regular long carbon chain structure, e.g., in particular C16-C30 fatty alcohol.

Preferably, the useful C16-C30 fatty alcohol can be saturated fatty alcohol having a hydrocarbon-based chain.

For the purpose of the invention, the term "saturated" fatty alcohol means any alcohol comprising a linear saturated (containing no covalent double or triple bonds) hydrocarbon-based chain, in particular a linear alkyl radical, said chain comprising between 16 and 22 carbon atoms and a hydroxyl function.

For the purpose of the invention, the term "hydrocarbon-based chain" means an organic group consisting essentially of, or even consisting of, hydrogen atoms and carbon atoms.

Advantageously, the C16-C30 fatty alcohol is chosen from C16-C22 fatty alcohols, preferably from C16-C18 fatty alcohols.

The saturated C16-C22 fatty alcohol (s) that are of use in the context of the present invention are notably chosen from cetyl alcohol or hexadecanol (C ₁₆) , stearyl alcohol or octadecanol (C ₁₈) , or behenyl alcohol (C ₂₂) which are solid at room temperature and advantageously bear a chain-end-OH group.

Particularly preferably, use will be made of one or more alcohols chosen from cetyl alcohol, stearyl alcohol, and mixtures thereof, such as cetylstearyl alcohol.

Preferably, the composition according to the invention comprises a mixture of C ₁₆ and C ₁₈ fatty alcohols; in particular, the composition comprises cetylstearyl alcohol.

More preferably, the mixture of C ₁₆ and C ₁₈ fatty alcohols is used in a C ₁₆/C ₁₈ mass ratio ranging from 20/80 to 80/20 and advantageously in a C ₁₆/C ₁₈ mass ratio equal to 50/50.

The wax may be present in an amount ranging for example from 0.1 to 10%by weight, preferably 0.5 to 5%by weight and more preferably from 1 to 3%by weight relative to the total weight of the composition.

According to an embodiment of the present invention, the emulsifier and wax are used at a ratio by weight ranging from 1/2 to 1/15, preferably 1/3 to 1/10, or alternatively 1/3 to 1/5.

Oil phase

As stated above, for example, the composition according to the present invention can be provided in a form of an oil-in-water (O/W) emulsion, comprising an oil phase and an aqueous phase. Accordingly, the component C) , i.e., the wax, is preferably present in the oil phase.

According to the present invention, the composition comprises at least one oil in the oil phase.

Oil

According to the present invention, the term “oil” refers to any fatty body in liquid form at room temperature (20-25℃) and atmospheric pressure. These oils may be of animal, plant, mineral or synthetic origin.

The oils may be volatile or non-volatile.

The term "volatile oil" refers to any non-aqueous medium capable of evaporating from the skin or lips, in less than one hour, at room temperature (20-25℃) and atmospheric pressure (760 mmHg) .

More specifically, the volatile oil is a volatile cosmetic oil, liquid at room temperature. More specifically, a volatile oil has an evaporation rate of between 0.01 and 200mg/cm ²/min, inclusive.

The term "non-volatile oil" is intended to mean an oil remaining on the skin or keratin fiber at ambient temperature and atmospheric pressure.

More specifically, a non-volatile oil has an evaporation rate strictly below 0.01 mg/cm ²/min.

To measure this evaporation rate, 15g of oil or a mixture of oils to be tested are introduced into a crystallizer, 7cm in diameter, placed on a scale located in a large 0.3m ³ chamber temperature-controlled at a temperature of 25℃, and humidity-controlled with a relative humidity of 50%. The liquid is left to evaporate freely, without stirring, by providing ventilation with a fan (PAPST-MOTOREN, reference 8550 N, rotating at 2700 rpm) positioned vertically above the crystallizer containing the solvent, with the blades directed toward the crystallizer and at a distance of 20cm from the base of the crystallizer. The mass of oil remaining in the crystallizer is measured at regular intervals. The evaporation rates are expressed in mg of oil evaporated per surface area unit (cm ²) and per time unit (minute) .

The oils that are suitable for the present invention may be hydrocarbon-based, silicone-based or fluorine-based.

According to the present invention, the term "silicone oil" refers to an oil including at least one silicon atom, and in particular at least on Si-O group.

The term "fluorine oil" refers to an oil including at least one fluorine atom.

The term "hydrocarbon-based oil" refers to an oil containing primarily hydrogen and carbon atoms.

The oils may optionally include oxygen, nitrogen, sulfur and/or phosphorus atoms, for example, in the form of hydroxyl or acid radicals.

More preferably, the composition of the present invention comprises hydrocarbon oil (s) .

Specifically, the volatile oils may be chosen from hydrocarbon oils having 8 to 16 carbon atoms, and in particular branched C ₈-C ₁₆ alkanes (also called isoparaffins or isoalkanes) , such as isododecane (also called 2, 2, 4, 4, 6-pentamethylheptane) , isodecane, isohexadecane, and, for example, the oils sold under the trade names

or

It is also possible to cite, as a hydrocarbon volatile oil, linear C ₉-C ₁₇ alkanes, such as dodecane (C ₁₂) and tetradecane (C ₁₄) , sold respectively under the names

12-97 and

14-97 (Sasol) , and, as alkanes obtained according to the method described in the international application WO 2007/068371 A1, such as the undecane (C ₁₁) and tridecane (C ₁₃) mixture sold under the name

UT (Cognis) .

The non-volatile oils may, in particular, be chosen from among the non-volatile hydrocarbon oils.

It is possible to cite, as a non-volatile hydrocarbon oil:

- hydrocarbon oils of animal origin, such as perhydrosqualene,

- hydrocarbon oils of plant origin, such as phytostearyl esters, for instance phytostearyl oleate, phytostearyl isostearate and lauroyl/octyldodecyl/phytostearyl glutamate (AJINOMOTO, ELDEW PS203) , diesters such as diisopropyl sebacate, triglycerides constituted of fatty acid esters of glycerol, in particular in which the fatty acids may have chain lengths ranging from C ₄to C ₃₆, and in particular from C ₁₈ to C ₃₆, it being possible for these oils to be linear or branched, and saturated or unsaturated; these oils may in particular be heptanoic or octanoic triglycerides, shea oil, alfalfa oil, poppy seed oil, pumpkin oil, millet oil, barley oil, quinoa oil, rye oil, candlenut oil, passionflower oil, shea butter, aloe oil, sweet almond oil, peach kernel oil, groundnut oil, argan oil, avocado oil, baobab oil, barrage oil, broccoli oil, calendula oil, camelina oil, canola oil, carrot oil, safflower oil, hemp oil, rapeseed oil, cotton seed oil, coconut oil, marrow seed oil, wheat germ oil, jojoba oil, lily oil, macadamia oil, corn oil, meadowfoam oil, St. John's Wort oil, monoi oil, hazelnut oil, apricot kernel oil, nut oil, olive oil, evening primrose oil, palm oil, blackcurrant seed oil, kiwi seed oil, grape seed oil, pistachio oil, pumpkin oil, winter squash oil, quinoa oil, musk rose oil, sesame oil, soya oil, sunflower oil, castor oil and watermelon oil, and mixtures thereof, or alternatively caprylic/capric acid triglycerides, for instance those sold by the STEARINERIES DUBOIS company or those sold under the names MIGLYOL

and

by the DYNAMIT NOBEL company,

- linear or branched hydrocarbons of mineral or synthetic origin, such as liquid paraffins and derivatives thereof, petroleum jelly, polydecenes, polybutenes, hydrogenated polyisobutene such as Parleam, squalane;

- synthetic ethers having from 10 to 40 carbon atoms;

- synthetic esters, for instance oils of formula R ₁COOR ₂, in which R ₁ represents a linear or branched fatty acid residue containing from 1 to 40 carbon atoms, and R ₂ represents a hydrocarbon-based chain, in particular a branched chain, containing from 1 to 40 carbon atoms provided that R ₁ or R ₂is greater than or equal to 10. The esters may in particular be selected from esters of fatty acid and of alcohol, for instance: cetostearyl octanoate, isopropyl alcohol esters, such as isopropyl myristate, isopropyl palmitate, ethyl palmitate, 2-ethylhexyl palmitate, isopropyl stearate or isostearate, isostearyl isostearate, octyl stearate, hydroxylated esters, for instance isostearyl lactacte, octyl hydroxystearate, diisopropyl adipate, heptanoates, and especially isostearyl heptanoate, alcohol or polyalcohol octanoates, decanoates or ricinoleates, for instance propylene glycol dioctanoate, cetyl octanoate, tridecyl octanoate, 2-ethylhexyl 4-diheptanoate and palmitate, alkyl benzoate, polyethylene glycol diheptanoate, propylene glycol 2-diethylhexanoate, and mixtures thereof, C ₁₂-C ₁₅ alkyl benzoates, hexyl laurate, neopentanoic acid esters, for instance isodecyl neopentanoate, isotridecyl neopentanoate, isostearyl neopentanoate, or octyldodecyl neopentanoate, isononanoic acid esters, for instance isononyl isononanoate, isotridecyl isononanoate and octyl isononanoate, hydroxylated esters such as isostearyl lactate and diisostearyl malate;

- polyol esters and pentaerythritol esters, for instance dipentaerythrityl tetrahydroxystearate/tetraisostearate,

- esters of diol dimers and diacid dimers, such as Lusplan

and Lusplan

sold by the NIPPON FINE CHEMICAL company and described in the application US 2004-175338,

- copolymers of a diol dimer and of a diacid dimer and esters thereof, such as copolymers of dilinoleyl diol dimers/dilinoleic dimers and esters thereof, for instance Plandool-G,

- copolymers of polyols and of diacid dimers, and esters thereof, such as Hailuscent ISDA, or the copolymer of dilinoleic acid/butanediol,

- fatty alcohols that are liquid at ambient temperature, with a branched and/or unsaturated carbon chain having from 12 to 26 carbon atoms, for instance 2-octyldodecanol, isostearyl alcohol, oleyl alcohol, 2-hexyldecanol, 2-butyloctanol and 2-undecylpentadecanol,

- C ₁₂-C ₂₂, higher fatty acids, such as oleic acid, linoleic acid or linolenic acid, and mixtures thereof, and,

- dialkyl carbonates of the following formula (I) :

wherein R ₁ and R ₂, identical or different, each represents a linear or branched hydrocarbon chain comprising from 3 to 30 carbon atoms.

Preferably, according to an embodiment, in formula (I) , R ₁ and R ₂, which are identical, represent a linear hydrocarbon chain comprising from 3 to 8 carbon atoms.

More preferably, the dialkyl carbonate is dicaprylyl carbonate.

In one embodiment, the carbonate is caprylyl carbonate. the two alkyl chains possibly being identical such as the dicaprylyl carbonate sold under the name CETIOL

by COGNIS.

- oils of higher molar mass having in particular a molar mass ranging from approximately 400 to approximately 10,000 g/mol, in particular from approximately 650 to approximately 10,000 g/mol, in particular from approximately 750 to approximately 7500 g/mol, and more particularly ranging from approximately 1000 to approximately 5000 g/mol. As oils of higher molar mass that can be used in the present invention, mention may in particular be made of the oils selected from:

● lipophilic polymers,

● linear fatty acid esters having a total carbon number ranging from 35 to 70,

● hydroxylated esters,

● aromatic esters,

● esters of C ₂₄-C ₂₈ branched fatty acids or fatty alcohols,

● oils of plant origin,

● and mixtures thereof; and

- mixtures thereof.

In one embodiment, the composition of the present invention comprises, as oil, dicaprylyl carbonate and/or octyldodecanol.

In one embodiment, the composition of the present invention is free of silicone oil.

As stated above, for the purpose of the invention, an “oil” is distinguished from a “wax” . In order to formulate an emulsion, it is advantageous to use concurrently a wax and an oil in the composition.

According to a preferred embodiment, the at least one oil (a) is present in an amount ranging from 0.1%to 15%by weight, preferably ranging from 1%to 10%by weight, relative to the total weight of the composition.

Method and use

The composition according to the present invention can be generally prepared according to the general knowledge of a person skilled in the art. Nevertheless, it is to be understood that a person skilled in the art can choose the method of preparation, on the basis of his/her general knowledge, taking into account the nature of the constituents used, for example, their solubility in the vehicle, and the application envisaged for the compositions or the composition.

According to an embodiment, the composition according to the present invention can be used for caring for keratin material, e.g., skin, especially for sensitive skin. This use may manifest itself as a process for caring for keratin material, e.g., skin, especially sensitive skin, comprising the steps of compounding the composition, and then applying to said skin the thus obtained composition.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the present invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective measurements. The following examples are intended to illustrate the present invention without limiting the scope as a result.

EXAMPLES

The ingredient amounts/concentrations in the compositions/formulas described below are expressed in %by weight, relative to the total weight of each composition/formula.

Example 1

The inventive compositions A1 to A3, and comparative compositions B1 to B3 were prepared.

Table 1

Protocol of preparation the compositions in table 1 comprises:

1) . mixing the components of the aqueous phase, adding the aqueous phase at room temperature into main kettle and heat to 80 ℃, and mixing until uniform; and

2) . introducing the components of the oil phase into main kettle, heating to 85 ℃, and mixing until uniform.

Example 2

Performance of the inventive compositions A1 to A3, and comparative compositions B1 to B3 were determined.

Epi-skin test for the compositions were carried out. In this in vitro test, compositions A1 to A3, and comparative compositions B1 to B3 were applied on Epi-skin model, each at an amount of 5g. Then irritants (lactic acid, conventionally used as irritant in the art) were added into the model. For comparison, irritant alone, and a simple combination of water and irritant at a weight ratio of 1: 9, were also applied, each at an amount of 1g.

After 24h, the cell viability of Epi-skin model was evaluated. The results were shown in Figure 1.

In both Figures 1 and 2, the samples labeled as "EX. 1" to "EX. 3" in the drawing denoted compositions A1 to A3, while the sample labeled as "CE. 1" to "CE. 3" in the drawing denoted compositions B1 to B3.

In figure 1, compositions A1, A2 and A3 showed good cell viability in Epi-skin model (all above 50%) , while compositions B1, B2 and B3 showed poor performance in cell viability in Epi-skin model.

Example 3

In order to further observe the structure of composition, Cryo-SEM was applied to study the compositions A2 and B2.

Referring to Fig. 2, it was clear to see that in composition A2, both liquid crystal and nature polysaccharide can be observed, while in composition B2, only liquid crystal structure was found. No net structure was observed in composition B2.

The foregoing description illustrates and describes the present disclosure. Additionally, the disclosure shows and describes only the preferred embodiments of the disclosure, but, as mentioned above, it is to be understood that it is capable of changes or modifications within the scope of the concept as expressed herein, commensurate with the above teachings and/or skill or knowledge of the relevant art. The described hereinabove are further intended to explain best modes known of practicing the disclosure and to enable others skilled in the art to utilize the disclosure in such, or other embodiments and with the various modifications required by the particular applications or uses disclosed herein. Accordingly, the description is not intended to limit the disclosure to the form disclosed herein. Also it is intended that the appended claims be construed to include alternative embodiments.

All publications, patents and patent applications cited in this specification are herein incorporated by reference, and for any and all purposes, as if each individual publication, patent or patent application were specifically and individually indicates to be incorporated by reference. In this case of inconsistencies, the present disclosure will prevail.

Claims

A composition, comprising the components of:

A) a natural polysaccharide having a molecular weight of 5,000-500,000;

B) an emulsifier selected from amphoteric and/or anionic surfactant; and

C) a wax.
Composition according to the preceding claim 1, wherein the natural polysaccharide is selected from the group consisting of polysaccharides produced by microorganisms and polysaccharides from higher plants, preferably from the group consisting of xanthan gum, sclerotium gum, e.g., scleroglucan gum, guar gum, inulin and pullulan.
Composition according to anyone of the preceding claims, wherein the natural polysaccharide has a molecular weight of 10,000-200,000, or preferably 30,000-100,000.
Composition according to anyone of the preceding claims, comprising an amphoteric surfactant, wherein the amphoteric surfactant is selected from the group consisting of betaines, such as (C8-C20) alkylbetaines, sulfobetaines, (C8-C20) alkylsulfobetaines, (C8-C20) alkylamido (C1-C6) alkylbetaines such as cocamidopropylbetaine, and (C8-C20) alkylamido (C1-C6) alkylsulfobetaines; amino acids, such as glycine, (C8-C20) alkyl polyaminocarboxylates; (C8-C20) alkylamphoacetates, (C8-C20) alkylamphodiacetates; lecithins; salts thereof; derivatives thereof and mixtures thereof, e.g., hydrogenated lecithin.
Composition according to claim 4, further comprising an anionic surfactant.
Composition according to anyone of the preceding claims, wherein the anionic surfactant is selected from the group consisting of alkali metal, alkaline earth metal or ammonium salt of: carboxylate, sulfate, sulfonate, sulfoacetate, sulfosuccinate, phosphate, isethionate, sarcosinate, glutamate, lactylate or taurate.
Composition according to anyone of the preceding claims, wherein the emulsifier is present in an amount ranging from 0.1 to 3%by weight, preferably 0.2 to 3%by weight and more preferably from 0.2 to 1%by weight relative to the total weight of the composition.
Composition according to anyone of the preceding claims, wherein the wax is selected from the group C16-C30 fatty alcohol, preferably C16-C22 fatty alcohols, or preferably C16-C18 fatty alcohols.
Composition according to anyone of the preceding claims, wherein the wax is selected from the group consisting of cetyl alcohol, stearyl alcohol, and mixtures thereof, such as cetylstearyl alcohol, e.g., in a C ₁₆/C ₁₈ mass ratio ranging from 20/80 to 80/20.
Composition according to anyone of the preceding claims, wherein the wax is present in an amount ranging for example from 0.1 to 10%by weight, preferably 0.5 to 5%by weight and more preferably from 1 to 3%by weight relative to the total weight of the composition.
Composition according to anyone of the preceding claims, wherein the the emulsifier and wax are used at a ratio by weight ranging from 1/2 to 1/15, preferably 1/3 to 1/10, or alternatively 1/3 to 1/5.
Composition according to anyone of the preceding claims, wherein the composition is provided in a form of an oil-in-water emulsion, comprising an aqueous phase comprising the component A) and the component B) , and an oil phase comprising the component C) .
Use of the composition according to anyone of the preceding claims for caring for keratin materials, e.g., for skin, in particular for sensitive skin.