WO2016174041A1

WO2016174041A1 - Topical composition for improving the duration of an immediate makeup and/or care effect

Info

Publication number: WO2016174041A1
Application number: PCT/EP2016/059305
Authority: WO
Inventors: Isabelle COLINET; Julien Laboureau
Original assignee: L'oreal
Priority date: 2015-04-29
Filing date: 2016-04-26
Publication date: 2016-11-03
Also published as: FR3035588A1; FR3035588B1

Abstract

The present invention relates to a composition, especially a cosmetic composition, for topical application, comprising, in a physiologically acceptable medium: (A) at least one photo-crosslinkable compound comprising at least one activated photo-dimerizable group bearing at least one activated double bond; (B) particulate starch in swollen form; and (C) at least one plasticizing system comprising at least one C₂-C₅ polyalkylene glycol and at least one C₂-C₆ polyol other than a polyalkylene glycol.

Description

TOPICAL COMPOSITION FOR IMPROVING THE DURATION OF AN IMMEDIATE MAKEUP AND/OR CARE EFFECT

The present invention relates to the field of making up and/or caring for keratin materials, in particular the skin, the lips, the hair and/or the nails, and is more particularly directed towards proposing novel technology for significantly increasing the duration of an immediate makeup and/or care effect.

The improvement in terms of duration of the immediate makeup and/or care effects on keratin materials is an ongoing concern.

At the present time, the technical solutions proposed do not make it possible to ensure maintenance of these immediate effects beyond a few hours. The impairment observed over time is generally due to physiological manifestations, which may be linked to environmental phenomena, for instance the secretion of sebum or sweat, or else mechanical constraints generated by the repeated movement of the subcutaneous facial muscles. Moreover, the performance qualities of certain additives, dedicated especially to care, could be optimized, especially by preventing their premature degradation, for example on contact with an aqueous medium (sweat, tears, etc.).

One of the means currently proposed for prolonging an immediate makeup and/or care effect consists in forming on the keratin material a film that is capable of resisting water and mechanical stress. Such a film may be formed by a physically or chemically crosslinked network.

However, a physically crosslinked network is, in general, less resistant to water and to mechanical stress than a chemically crosslinked network. As regards the chemically crosslinked network, which is more resistant, it usually requires the use of a crosslinking catalyst. It may especially be an oxidizing agent of peroxide type, and thus aggressive, and/or a temperature increase. Films derived from photochemical crosslinking thus prove to be more advantageous provided that their formation does not require a photoinitiator or high-energy stimulation. Recently, the inventors have found that a photo-crosslinkable polymer bearing at least one stilbazolium or styrylazolium group, which is very sensitive to light, proves to be most particularly advantageous for forming, simply (low level of energy required, absence of photoinitiator) and entirely harmlessly, a persistent, elastic, crosslinked film at the surface of a keratin material. US 2013/317 416 proposes an injectable composition containing a photo-crosslinkable polymer for the purposes of filling wrinkles and hiding skin relief imperfections. However, this composition, which is intended to be injected, is not directed towards addressing the problems of developing a persistent, elastic and resistant film at the surface of a keratin material. The object of the present invention is, precisely, to propose a novel formulation that is capable of forming, after photo-crosslinking, a film that efficiently satisfies all of these expectations.

According to a first aspect, a subject of the invention is a composition, especially a cosmetic composition, for topical application, comprising, in a physiologically acceptable medium:

(A) at least one photo-crosslinkable compound functionalized with one or more hydroxyl functions, and comprising at least one activated photo-dimerizable group bearing at least one activated double bond;

(B) particulate starch in swollen form; and (C) at least one plasticizing system comprising at least one C2-C5 polyalkylene glycol and at least one C2-C6 polyol other than a polyalkylene glycol.

Advantageously, the photo-dimerizable group(s) of the photo-crosslinkable compound (A) according to the invention are chosen from: a) photo-dimerizable group(s) bearing a stilbazolium function of formula (la) or (lb):

in which:

- R represents a hydrogen atom or a C₁-C₄ alkyl or C₁-C₄ hydroxyalkyl group,

- R' represents a hydrogen atom or a C₁-C₄ alkyl group, and

- X- denotes an ion chosen from chloride, bromide, iodide, perchlorate, tetrafluoroborate, methyl sulfate, phosphate, sulfate, methanesulfonate and p-toluenesulfonate ions;

in which:

- R' ' denotes a divalent alkylene radical containing from 2 to 8 carbon atoms,

- R' represents a hydrogen atom or a C₁-C₄ alkyl group, and

- X- has the same meaning as that described for the preceding formula (la); or b) photo-dimerizable groups bearing a styrylazolium function of formula (II):

in which:

- Ri denotes a hydrogen atom or a C₁-C₄ alkyl or C₁-C₄ hydroxyalkyl group;

- A denotes a sulfur atom, an oxygen atom or an NR' or C(R')2, R' group; with R' representing a hydrogen atom or a C₁-C₄ alkyl group, R' preferably representing a hydrogen atom; and

- X- has the same meaning as that described for the preceding formula (la). According to a particular embodiment, a composition according to the invention may also comprise at least one additive (D), especially as defined below.

According to another of its aspects, the present invention relates to a crosslinked film, especially a cosmetic film, in particular for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, obtained by photochemical crosslinking with natural or artificial light of a composition according to the invention.

According to a first embodiment variant, the compound(s) for which it is sought to improve the persistence over time of the associated immediate makeup and/or care effect may already be present in a composition according to the invention. It is especially an additive (D) as defined below.

Thus, according to another of its aspects, the present invention relates to a cosmetic process for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, comprising at least the steps consisting in: (i) applying at the surface of said keratin material a coat of at least one composition according to the invention; and

(ii) exposing all or part of the surface of the coat formed in step (i) to conditions suitable for photochemical crosslinking to form a crosslinked film at the surface of said keratin material. Also, and according to another of its aspects, the present invention relates to a cosmetic process for improving the persistence over time, especially over a duration of greater than 4 hours, preferably greater than 8 hours, the adhesion to the keratin material and the resistance to water and to mechanical constraints (friction) of a cosmetic composition, especially for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, said process comprising at least the steps consisting in:

(i) extemporaneously incorporating into said cosmetic composition:

(A) at least one photo-crosslinkable compound as defined above;

(B) particulate starch in swollen form; and (C) at least one plasticizing system as defined above; and

(ii) applying at the surface of said keratin material a coat of the mixture obtained in step (i); and

(iii) exposing all or part of this surface to conditions suitable for photochemical crosslinking to form a crosslinked film at the surface of said keratin material.

Preferably, compounds (A) to (C) may be incorporated into the cosmetic composition in the form of a mixture.

According to a second embodiment variant, the compound(s) for which it is sought to improve the persistence over time of the associated immediate makeup and/or care effect may already be present on a keratin material.

Thus, according to another of its aspects, the present invention relates to the use of a composition according to the invention for forming a film at the surface of a keratin material coated beforehand with a separate cosmetic composition.

As emerges from the text hereinbelow, a film according to the invention has improved properties in terms of persistence over time, especially over a duration of greater than 4 hours, preferably greater than 8 hours, of adhesion to keratin material, of resistance to water and to mechanical constraints (friction) and of reversible mechanical deformations.

According to yet another of its aspects, the present invention relates to a cosmetic process for improving the persistence over time, especially over a duration of greater than 4 hours, preferably greater than 8 hours, and the resistance to water and to mechanical constraints (friction), of a first cosmetic composition, especially a makeup and/or care composition, applied beforehand to the surface of a keratin material, in particular the skin, the lips, the hair and/or the nails, said process comprising at least the steps consisting in:

(i) covering said first cosmetic composition applied beforehand to the surface of a keratin material with a coat of at least a second composition according to the invention; and (ii) exposing all or part of the surface of the coat formed in step (i) to conditions suitable for photochemical crosslinking of said second composition to form a crosslinked film at the surface of said first composition.

According to yet another of its aspects, the present invention relates to a kit for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, comprising at least:

- a first composition intended to afford a makeup and/or care effect on a keratin material, especially the skin, the lips, the hair and/or the nails,

- a second composition according to the invention, different from the first composition above; and

- optionally, at least one member intended for the mixing and/or sequential or extemporaneous application of said first and second compositions to the surface of said keratin material.

(A) PHOTO-CROSSLINKABLE COMPOUND The photo-crosslinkable compounds under consideration according to the invention comprise at least one activated photo-dimerizable group bearing at least one activated double bond.

The mean number of activated double bonds per molecule of compound is preferably greater than 1, in particular greater than 2 and better still greater than 3. For the purposes of the present invention, the term "photo-dimerizable group" means a chemical group that leads to photo-dimerization reactions under irradiation.

For the purposes of the present invention, the term "photo-dimerization" means a chemical reaction between two double bonds (of 2+2 type) or two pairs of double bonds (of 4+4 type), and more particularly between two double bonds (of 2+2 type).

Thus, the double bond under consideration according to the invention, when it is photo-stimulated or, in other words, subjected to specific radiation, generally UV, proves to be capable of reacting with another double bond by cyclization. As detailed below, the interacting double bonds are preferably ethylene functions, i.e. of the type CH₂=CH₂.

For the purposes of the invention, the double bond under consideration is said to be activated. This characterization means that the double bond is spontaneously photo-dimerizable in response to a light stimulus, without requiring the mandatory presence of a photoinitiator or a chemical initiator.

Consequently, a composition according to the invention is advantageously free of photoinitiator and/or of chemical initiator.

Activation of the double bond intended to be dimerized is commonly induced by the presence in proximity thereto, generally in the alpha position, of an electron-withdrawing group, for instance an aromatic nucleus such as a phenyl.

The case of a reaction between two double bonds may be represented schematically in the following manner:

These photo-dimerization reactions are defined in the book Advanced Organic Chemistry, J. March, 4th edition, Wiley Interscience, NY 1992, page 855.

The materials bearing photo-dimerizable groups according to the invention have the advantage of being stable with respect to oxygen, moisture and heat, and of leading to a reversible crosslinking.

In addition, the photo-dimerizable groups according to the invention are highly photosensitive. Consequently, even low-energy irradiation leads to rapid and efficient crosslinking of the material, which, in the case of an application in cosmetics, induces short-lasting and low-energy irradiation, which does not lead to degradation of the keratin materials.

The activated photo-dimerizable groups that may be used according to the invention are chosen from: a) photo-dimerizable groups bearing a stilbazolium function of formula (la) or (lb):

in which:

- R represents a hydrogen atom or a C₁-C₄ alkyl or C₁-C₄ hydroxyalkyl group; preferably, R represents a hydrogen atom, a methyl group, an ethyl group or a hydroxy ethyl group; preferentially, R is a methyl group;

- R' represents a hydrogen atom or a C₁-C₄ alkyl group; preferably, R' represents a hydrogen atom; and

- X^" denotes an ion chosen from chloride, bromide, iodide, perchlorate, tetrafluoroborate, methyl sulfate, phosphate, sulfate, methanesulfonate and p-toluenesulfonate ions; preferably, X^" is an ion chosen from chloride and methyl sulfate ions; preferentially, X^" is a methyl sulfate ion.

in which:

- R' ' denotes an alkylene radical (divalent) containing from 2 to 8 carbon atoms; preferably, R' ' denotes an alkylene radical (divalent) containing from 2 to 4 carbon atoms;

- R' represents a hydrogen atom or a C₁-C₄ alkyl group, R' preferably representing a hydrogen atom; and

- X- has the same meaning as that described for the preceding formula (la), b) photo-dimerizable groups bearing a styrylazolium function of formula (II):

in which:

- A denotes a sulfur atom, an oxygen atom or an NR' or C(R')₂, R' group; with R' representing a hydrogen atom or a C₁-C₄ alkyl group, R' preferably representing a hydrogen atom; and

- X- has the same meaning as that described for the preceding formula (la).

Such chemical groups bear activated double bonds, and as such the photo-dimerization of these double bonds starts spontaneously in the UVA range, without requiring a photoinitiator.

According to a preferred embodiment, the photo-dimerizable groups that may be used according to the invention bear a stilbazolium function of formula (la):

in which:

- R' represents a hydrogen atom or a C₁-C₄ alkyl group, and

- X^" denotes an ion chosen from chloride, bromide, iodide, perchlorate, tetrafluoroborate, methyl sulfate, phosphate, sulfate, methanesulfonate and p-toluenesulfonate ions.

The photo-crosslinkable compound is derived from the functionalization of a natural backbone, preferably polymeric, with at least one photo-dimerizable group. This functionalization falls within the competence of a person skilled in the art.

These polymer backbones are preferably chosen from natural polymers such as polysaccharides and synthetic polymers such as partially or totally hydrolyzed polyvinyl acetate and polyvinyl alcohol (PVA). Advantageously, in the compositions of the invention, the compound comprising at least one photo-dimerizable group is derived from a hydrocarbon-based polymer or copolymer in which the repeating unit or at least one of the repeating units bears at least one hydroxyl group. This compound is preferably chosen from polyvinyl alcohol, totally or partially hydrolyzed polyvinyl acetate and polysaccharides chosen from chondroitin sulfate, keratan, keratan sulfate, heparin, heparin sulfate, xanthan, carrageenan, chitosan, cellulose and derivatives thereof, alginate, starch, dextran, pullulan, galactomannan and biologically acceptable salts thereof, and also derivatives thereof.

Even more advantageously, this compound is in the form of particles, in particular of dispersed particles. Thus, in the latter case, the polymer particles are very preferentially polyvinyl alcohol particles, preferably with a size of between 0.1 and 5 μιη and more particularly between 0.1 and 1 μιη.

According to a particularly preferred embodiment of the invention, the photo-crosslinkable compound according to the invention may bear one or more functions that are cyclizable in a 2/2 reaction and that are sensitive to light irradiation, in particular in the absence of a photoinitiator and/or of a chemical initiator.

Preferably, a photo-crosslinkable compound comprises at least one photo-dimerizable unit endowed with a photo-dimerizable activated double bond, borne by a polymer such as a partially or totally hydrolyzed polyvinyl acetate, a polysaccharide or a polyvinyl alcohol. As regards the compounds containing photo-dimerizable groups bearing a stilbazolium function, they are obtained by reaction of the polymer under consideration with a chemical species comprising a group of formula (la) or (lb). Preferably, the chemical species comprising a group (la) bears a reactive group W of aldehyde or acetal type.

In other words, this chemical species corresponds to the general formula W-A, with A denoting the group (la). As chemical species that may be used to graft groups of styrylpyridinium type, mention may be made especially of quaternary salts of 2-(4-formylstyryl)pyridinium, 4-(4-formylstyryl)pyridinium, 2-(3 -formylstyryl)pyridinium,

N-methyl-2-(4-formylstyryl)pyridinium, N-methyl-3-(4-formylstyryl)pyridinium, N-methyl-2-(3-formylstyryl)pyridinium, N-methyl-2-(2-formylstyryl)pyridinium, N-ethyl-2-(4-formylstyryl)pyridinium, N-(2-hydroxyethyl)-2-(4-formylstyryl)pyridinium, N-(2-hydroxyethyl)-4-(4-formylstyryl)pyridinium, N-methyl-4-(4-formylstyryl)pyridinium and N-methyl-4-(3-formylstyryl)pyridinium.

The pyridinium quaternary salts may be chloride, bromide, iodide, perchlorate, tetrafluoroborate, methosulfate, phosphate, sulfate, methanesulfonate or p-toluenesulfonate salts. Such chemical species are described in GB-A-2 030 575.

Examples of species that may be mentioned include 4-(4-formylphenylethenyl)- 1 -methylpyridinium methosulfate, 1 -(3-ethoxycarbonylmethyl)-4-[2-(4-formylphenyl)ethenyl]pyridinium bromide and 1 -(methoxycarbonylpropyl)-4-[2-(4-formylphenyl)ethenyl]pyridinium bromide. Such species are described in US 2007/0 112 094.

Use is preferably made of n-methyl-4-(4-formylstyryl)pyridinium methyl sulfate (RN= 74401-04-0), sold especially by the company Wako.

Advantageously, the chemical species of formula W-A react with a polymer of polyvinyl alcohol or polyvinyl acetate type as described in the documents mentioned previously. For example, a polyvinyl alcohol grafted polymer comprising units having following structure is thus obtained:

Polyvinyl alcohol polymers grafted with a styrylpyridinium group are especially described in the publication Ichimura K. et al, Preparation and characteristics of photo-crosslinkable polyvinyl alcohol), Journal of Polymer Science, Polymer Chemistry Edition, Vol. 20, 1419-1432 (1982). The polymers may be obtained by reacting polyvinyl alcohol or partially hydro lyzed polyvinyl acetate with styrylpyridinium salts bearing a formyl or acetal group as described in GB-A-2 030 575, WO 96/29312, US 5 061 603, GB-A-2 076 826 and EP-A-092 901.

Cellulose polymers grafted with styrylpyridinium groups are especially described in US 2007/0112094.

Preferably, the chemical species comprising a group (la) bears a reactive group which is a chlorine atom.

In this variant, the chemical species corresponds to a general formula Cl-A', with A' denoting the group (la).

As chemical species of the type Cl-A', use is preferably made of that of

Advantageously, the photo-crosslinkable compound comprising the groups (lb) is advantageously obtained by reaction of the species Cl-A' with the polysaccharide chosen from those defined previously, in the presence of water.

As regards the compounds containing photo-dimerizable groups bearing a styrylazolium function, they are obtained by reaction of the polymer with a chemical species comprising a group of formula (II).

Preferably, the chemical species comprising a group (II) bears a reactive group W of aldehyde or acetal type.

In other words, the chemical species corresponds to the general formula W-B, with B denoting the group (II).

As chemical species that may be used to graft groups of styrylazolium type, mention may be made of those described in EP-A-313 220.

Advantageously, these chemical species of formula W-B react with a polymer of polyvinyl alcohol or polyvinyl acetate type as described in the documents mentioned previously.

A polyvinyl alcohol grafted polymer comprising units having the following structure is thus obtained:

Polyvinyl alcohol polymers grafted with styrylazolium groups are described especially in EP-A-313 220. In said document, these polymers may be obtained by reaction of polyvinyl alcohol or partially hydrolyzed polyvinyl acetate with styrylazolium salts bearing an aldehyde or acetal group. Preferably, the polymer bearing (a) photo-dimerizable group(s) is in the form of particles, in particular of dispersed particles. Thus, in this latter case, the polymer particles are very preferentially polyvinyl alcohol particles.

Thus, according to one embodiment variant, the photo-crosslinkable compound is a polyvinyl alcohol (PVA) partly functionalized with one or more hydroxyl functions and one or more functions of formula III):

5000.

Advantageously, the polymer has a degree of substitution, as a percentage of functions of formula (la), (lb) or (II) as defined above, which may be between 0.1 and 25.

The following scheme represents a variant in which the polymer is PVA-SbQ

(polymer of polyvinyl alcohol PVA type bearing a few hydrolyzed functions and a few functions grafted with stilbazolium species), which is capable of crosslinking under the effect of light, as illustrated below.

These materials are particularly appreciated since they do not require a photoinitiator and react with visible light or with radiation that may comprise both UV light and visible light, in particular a low dose of UV.

By way of example, mention may be made of PVA-SbQ (poly( vinyl alcohol)) with N-methylstyrylpyridinium pendent groups in methyl sulfate salt form, sold under the reference MQ2012 by the company Murakami, especially in the form of a dispersion at 13.3% by weight in water, for example of CAS number: 107845-59-0.

According to another embodiment variant, the photo-crosslinkable compound is featured by a polysaccharide which is functionalized with photo-dimerizable groups. It may especially be a polysaccharide that may especially be chosen from chondroitin sulfate, keratan, keratan sulfate, heparin, heparin sulfate, xanthan, carrageenan, chitosan, cellulose and derivatives thereof, alginate, starch, dextran, pullulan, galactomannan and biologically acceptable salts thereof.

The degree of functionalization is obviously adjusted to be able to impart the desired degree of crosslinking to the film intended to be formed by photo-crosslinking using a UV source, especially natural or artificial light, of a composition according to the invention, and which is especially required during step (ii) of the process of the invention.

According to the invention, the degree of functionalization with photo-dimerizable units is at least 0.1%, or even at least 0.5%, or even at least 2%. As stated previously, in a composition according to the invention, the photo-dimerizable groups are preferably borne by a polymer of polyvinyl acetate type, a polyvinyl alcohol or a polysaccharide.

Preferably, in a composition according to the invention, the photo-dimerizable groups are borne by a polyvinyl alcohol. According to a particularly preferred embodiment of the invention, the photo-crosslinkable compound(s) (A) according to the present invention are represented by a polyvinyl alcohol (PVA) partly functionalized with one or more hydro xyl functions and one or more photo-dimerizable groups bearing a stilbazolium or styrylazolium function. The photo-crosslinkable compound may be conveyed in a physiologically acceptable medium and in particular an aqueous medium or even in pure water.

The photo-crosslinkable compound may have a number-average molecular weight ranging from 2000 to 500 000, preferably from 2000 to 100 000 and better still from 2000 to 20 000.

According to another particular embodiment, the photo-crosslinkable compound may be chosen from polyurethane and/or polyurea polymers or oligomers bearing (meth)acrylate groups, in particular polyurethane (meth)acrylate oligomers.

Such polyurethanes/polyureas bearing acrylate groups are sold, for example, under the name Ebecryl^® by the company Cytec (Ebecryl^® 210: molar mass 1500, 2 acrylate functions per molecule, Ebecryl^® 230: molar mass 5000, 2 acrylate functions per molecule, Ebecryl^® 270: molar mass 1500, 2 acrylate functions per molecule, Ebecryl^® 8402: molar mass 1000, 2 acrylate functions per molecule, Ebecryl^® 8804: molar mass 1300, 2 acrylate functions per molecule, Ebecryl^® 220: molar mass 1000, 6 acrylate functions per molecule, Ebecryl^® 1290: molar mass 1000).

Mention may also be made of the water-soluble aliphatic acrylate polyurethanes sold under the names Ucecoat^® 6558 and Ucecoat^® 6569, and the acrylate polyurethanes in aqueous dispersion sold under the trade names Ucecoat^® 7571, Ucecoat^® 7578, Ucecoat^® 7655, Ucecoat^® 7674, Ucecoat^® 7689 and Ucecoat^® 7699 by the company Cytec.

These compounds are capable of crosslinking when they are subjected to radiation comprising at least one UV light.

An example that may be mentioned is diurethane methacrylate (INCI: Di-HEMA trimethylhexyl dicarbamate). The composition may contain a single photo-crosslinkable polymer bearing functions that may or may not be of different nature.

Use may also be made of a mixture of photo-crosslinkable polymers having different functions. Consequently, the reactions may take place between two photo-dimerizable groups that may or may not be of the same chemical nature.

The activated double bonds may react with another double bond of the same chemical nature or may react with another double bond of different chemical nature. The photo-crosslinkable compound may be soluble or dispersed in the composition used for its administration.

Preferably, the photo-crosslinkable compound under consideration according to the invention is chosen from polymers that are capable of crosslinking via a 2+2 cycloaddition reaction, in particular polymers bearing stilbazolium functions. According to a preferred embodiment variant, a photo-crosslinkable compound

(A) according to the invention may be used in a composition according to the invention in the form of an aqueous dispersion of a polymer of partially saponified (hydrolyzed) polyvinyl acetate type bearing stilbazolium groups, placed in contact, especially mixed, with polyvinyl acetate particles. As examples of commercial products of this type, mention may be made of

PVA-SbQ (poly(vinyl alcohol) with pendent pyridinium (and) polyvinyl acetate (PVAc)), sold under the references Emulsion AD-V5 F1PB and Emulsion AD-V5-10 F1PB by the company Murakami, especially in the form of an aqueous dispersion of PVA-SbQ particles, the content of which is between 10.7% and 11%, of PVAc particles at 3.56% and in which the percentage of water is between 85.2% and 85.6%.

The polyvinyl acetate (PVAc) particles may be present in a content of greater than 2% by weight, preferably greater than 3%, or may even be between 1% and 10% by weight, relative to the total weight of photo-crosslinkable compound(s) (A) comprising them.

More particularly, the photo-crosslinkable compound(s) (A) according to the invention is/are PVA-SbQ (poly(vinyl alcohol)) as described above plasticized with polyvinyl acetate (PVAc) particles. According to a particular embodiment, a composition according to the present invention may comprise from 0.1% to 5% by weight and preferably from 0.5% to 3.5% by weight of photo-crosslinkable compound(s) (A) relative to the total weight of the composition. As detailed above, the invention flows more particularly from the surprising observation by the inventors that the persistence, and similarly the mechanical properties, of a film derived from the crosslinking of a photo-crosslinkable compound (A) as defined above may be significantly improved provided that this crosslinking is performed in the presence of a particulate starch in swollen form and of a particular plasticizing system. (B) PARTICULATE STARCH IN SWOLLEN FORM

Starches are macromolecules in the form of polymers consisting of elementary moieties which are anhydroglucose units (dextrose), linked via a(l,4) bonds of chemical formula (C₆HioOs)_n. The number of these moieties and their assembly make it possible to distinguish amylose, a molecule formed from about 600 to 1000 linearly linked glucose units, and amylopectin, a polymer branched approximately every 25 glucose residues (a(l,6) bond). The total chain may include between 10 000 and 100 000 glucose residues.

Starch is described in particular in Kirk-Othmer's Encyclopaedia of Chemical Technology, 3rd edition, volume 21, pages 492-507, Wiley Interscience, 1983.

The relative proportions of amylose and of amylopectin, and their degree of polymerization, vary as a function of the botanical origin of the starches. On average, a sample of native starch consists of about 25% amylose and 75% amylopectin.

The botanical origin of the starch molecules used in the present invention may be cereals or tubers. Thus, the starches are chosen, for example, from corn starch, rice starch, cassava starch, tapioca starch, barley starch, potato starch, wheat starch, sorghum starch and pea starch. Use may also be made of the hydrolyzates of the starches mentioned above.

These starches are generally in the form of a white powder, which is insoluble in cold water, whose elemental particle size ranges from 1 to 100 microns. In the present invention, the starch is used in a particulate form, in swollen and non-split form.

A starch in swollen form according to the invention is a starch in which more than 80% of these swollen particles have a diameter of greater than 30 microns and more particularly greater than 100 microns. Thus, the size of the swollen and non-split particles may range from 10 to 300 μιη and preferably from 20 to 60 μιη.

This swelling may also be characterized by a swelling power Q which may advantageously be between 10 and 30 ml/g and preferably between 15 and 25 ml (volume of absorbed liquid)/g of dry particulate material. With regard to this swelling due to the penetration of water molecules into the starch particles, the starch has better affinity for water. What is more, with regard to its flexible structure and its chemical structure, it participates efficiently in the cohesion of the film via the establishment of physical interactions with the chains of the photo-crosslinkable compound(s) (A), in particular the chains of PVA-SbQ. The starches that are suitable for use in the present invention in swollen form may be chosen from native starches and modified starches, and mixtures thereof.

The native starches may be chosen from corn starch, rice starch, cassava starch, tapioca starch, barley starch, potato starch, wheat starch, sorghum starch and pea starch, and mixtures thereof. The native starches are represented, for example, by the products sold under the names C*Amilogel™, Cargill Gel™, C* Gel™, Cargill Gum™, DryGel™ and C*Pharm Gel™ by the company Cargill, under the name Corn Starch by the company Roquette, and under the name Tapioca Pure by the company National Starch.

The modified starches may be modified via one or more of the following reactions: pregelatinization, degradation (acid hydrolysis, oxidation, dextrinization), substitution (esterification, etherification), crosslinking (esterification), bleaching or hydrophobization. The modified starches are represented, for example, by the products sold under the names C*Tex-Instant (pregelatinized adipate), C*StabiT ex-Instant (pregelatinized phosphate), C*PolarT ex-Instant (pregelatinized hydroxypropyl), C*Set (acid hydrolysis, oxidation), C*size (oxidation), C*BatterCrisp (oxidation), C*DrySet (dextrinization), C*TexTM (acetyl distarch adipate), C*PolarTexTM (hydroxypropyl distarch phosphate), C* StabiTexTM (distarch phosphate, acetyl distarch phosphate) by the company Cargill, by distarch phosphates or compounds rich in distarch phosphate such as the product sold under the references Prejel VA-70-T AGGL (gelatinized hydroxypropyl cassava distarch phosphate) or Prejel TK1 (gelatinized cassava distarch phosphate) or Prejel 200 (gelatinized acetyl cassava distarch phosphate) by the company Avebe or Structure Zea from National Starch (gelatinized corn distarch phosphate).

The starches that are suitable for use in the invention may also be chosen from crosslinked starches (especially crosslinked with dimethyleneurea, epichlorohydrin or an acetyl group), starches modified by esterification (especially with octenylsuccinic anhydride groups), starch carboxymethyl ethers, starch glycolates, hydroxypropyl starches, and starches modified with hydrophobic groups or chains (especially C3-C24 alkyl chains).

It is within the capability of a person skilled in the art to obtain a particulate starch in swollen form. Generally, such starch may be obtained by heating a native or modified starch in the presence of a solvent, generally water, at a temperature of between 65 and 110°C, preferably between 90 and 105°C, and preferably for a time of between 1 hour 30 minutes and 10 hours and more particularly between 4 hours and 8 hours.

As particulate starches (B) or precursor of a swollen particulate starch that is suitable for use in the invention, the following may especially be mentioned:

- the starches described previously, where appropriate modified via one or more of the following reactions: pregelatinization, degradation (acid hydrolysis, oxidation, dextrinization), substitution (esterification, etherification), crosslinking (esterification), bleaching or hydrophobization;

- starches grafted with an acrylic polymer (homopolymer or copolymer) and especially with sodium polyacrylate, for instance those sold under the names Sanfresh ST-100MC by the company Sanyo Chemical Industries or Makimousse 25, Makimousse 12 by the company Daito Kasei (INCI name: Sodium polyacrylate starch);

- hydrolyzed starches grafted with an acrylic polymer (homopolymer or copolymer), and especially acryloacrylamide/sodium acrylate copolymer, for instance those sold under the names Water Lock A-240, A- 180, B-204, D-223, A- 100, C-200 and D-223 by the company Grain Processing (INCI name: Starch/acrylamide/sodium acrylate copolymer);

- polymers based on starch, gum and cellulose derivative, such as the product containing starch and sodium carboxymethylcellulose, for instance the product sold under the name Lysorb 220 by the company Lysac; - starches grafted with at least one C₁-C₄ carboxyalkyl group on at least one alcohol function of the starch, as described below; and

- mixtures thereof.

Also, a swollen particulate starch according to the invention may be derived from a (C₁-C₄) carboxyalkyl starch, also referred to hereinbelow as carboxyalkylstarch. These compounds are obtained by grafting carboxyalkyl groups onto one or more alcohol functions of starch, especially by reaction of starch and of sodium monochloroacetate in alkaline medium.

The carboxyalkyl starches are advantageously used in the form of salts and especially of salts of alkali metals or alkaline-earth metals such as Na, K, Li, NH₄, or salts of a quaternary ammonium or of an organic amine such as monoethanolamine, diethanolamine or triethanolamine. The (C₁-C4) carboxyalkyl starches are advantageously, in the context of the present invention, carboxymethyl starches. The carboxymethyl starches preferably comprise units having the following formula:

in which X, optionally covalently bonded to the carboxylic unit, denotes a hydrogen atom, an alkali metal or alkaline-earth metal such as Na, K, Li, N¾, a quaternary ammonium or an organic amine, for instance monoethanolamine, diethanolamine or triethanolamine. Preferably, X denotes an Na⁺ cation. The carboxyalkyl starches that may be used according to the present invention are preferably non-pregelatinized carboxyalkyl starches. The carboxyalkyl starches that may be used according to the present invention are preferably partially or totally crosslinked carboxyalkyl starches.

In general, a crosslinked carboxyalkyl starch has, in contrast with a non-crosslinked carboxyalkyl starch, an increased, controllable viscosity of increased stability. The crosslinking thus makes it possible to reduce the syneresis phenomena and to increase the resistance of the gel to shear effects.

The carboxyalkyl starches under consideration according to the invention are more particularly potato carboxyalkyl starches. Thus, the carboxyalkyl starches that may be used according to the present invention are preferably sodium salts of carboxyalkyl starches, in particular a sodium salt of potato carboxymethyl starch, sold especially under the name Primojel^® by the company DMV International or Glycolys^® and Glycolys^® LV by the company Roquette.

According to a particular mode, use will be made of the potato carboxymethyl starches sold especially under the name Glycolys^® by the company Roquette. Thus, the gel Primojel^® containing 10% by weight of potato carboxyalkyl starch and sodium salt in water contains more than 80% of swollen particles of this starch with a diameter of greater than 50 microns and more particularly greater than 100 microns.

According to a preferred embodiment variant of the invention, these particles are used for the preparation of the compositions according to the invention, in this swollen particulate state. To do so, these particles are advantageously used in the form of an aqueous gel either prepared beforehand or already commercially available. The gels under consideration according to the invention are advantageously translucent. For example, a carboxymethyl starch gel such as Primojel which is at a concentration of 10% by weight may be adjusted to the required concentration before being used for preparing the expected composition.

Advantageously, a composition according to the invention may comprise from 0.1% to 10% by weight, preferably from 0.5% to 5% by weight and more particularly from 1%) to 3%) by weight of swollen particulate starch (B) expressed as solids, relative to the total weight of the composition.

In point of fact, as emerges from the examples below, the production of a film that satisfies all the requirements discussed above involves combining the use of the photo-crosslinkable compound (A) and of the swollen starch particles (B) with a specific plasticizing system.

(C) PLASTICIZING SYSTEM

The plasticizing system (C) required according to the invention comprises at least one C2-C5 polyalkylene glycol and at least one C2-C6 polyol other than a polyalkylene glycol.

It has especially been observed by the inventors that the presence of such a plasticizing system in a composition according to the invention is advantageous for reinforcing the mechanical qualities of the film; specifically, breaking of the crosslinked film has been observed in the absence of such a plasticizing system. The C2-C5 polyalkylene glycol also contributes towards improving the capacity of the film to be reversibly deformed. In other words, it appears to give said film a certain elasticity and thus deformability properties.

C2-C5 Polyalkylene glycol

For the purposes of the present invention, a polyalkylene glycol has the following formula OH-(Alk-0)_x-H with:

- Alk denoting an alkyl group comprising from 2 to 5 carbon atoms and preferably from 2 to 3 carbon atoms, and - x denoting an integer between 3 and 50 and preferably between 4 and 20.

Preferably, a polyalkylene glycol in accordance with the invention may have a molar mass of greater than or equal to 200 g/mol, preferably greater than 250 g/mol and better still 350 g/mol.

Preferably, a polyalkylene glycol in accordance with the invention may be chosen from polyethylene glycol, polypropylene glycol and polybutylene glycol, and mixtures thereof, preferably polyethylene glycol and especially PEG-8 or polyglyco 1-400.

A composition according to the invention may advantageously comprise from 0.1% to 3% by weight, preferably from 0.25% to 2% by weight and better still from 0.5%> to 1.75%) by weight of C₂-C5 polyalkylene glycol(s) relative to the total weight of the composition.

C₂-C₆ Polyol

For the purposes of the present invention, the term "polyol" should be understood as meaning any organic molecule comprising at least two free hydroxyl groups. For the purposes of the present invention, this molecule may be of oligomeric nature, but, in any case, cannot be likened to a polymer such as the polyalkylene glycol detailed above.

Preferably, a polyol that is suitable for use in the invention may have a molar mass of less than 200 g/mol, preferably less than 140 g/mol and better still less than 100 g/mol.

Preferably, a polyol in accordance with the present invention is present in liquid form at room temperature.

A polyol that is suitable for use in the invention may be a compound of linear, branched or cyclic, saturated or unsaturated alkyl type, bearing on the alkyl chain at least two OH functions and in particular at least three OH functions.

The polyols that are advantageously suitable for formulating a composition according to the present invention are those especially containing from 2 to 6 carbon atoms and preferably 3 to 4 carbon atoms. Advantageously, a polyol according to the invention may be chosen from pentaerythritol, trimethylolpropane, propylene glycol, 1,3-propanediol, butylene glycol, isoprene glycol, pentylene glycol, hexylene glycol, glycerol, 1,5-pentanediol, dipropylene glycol, diglycerol, xylitol and stereoisomers thereof, sorbitol and stereoisomers thereof, and inositol and stereoisomers thereof, and mixtures thereof.

According to a preferred embodiment of the invention, said polyol is chosen from pentaerythritol, trimethylolpropane, propylene glycol, glycerol and diglycerols, and mixtures thereof.

According to another particular mode, the composition of the invention comprises at least glycerol.

A composition according to the invention may advantageously comprise from 0.1 % to 20% by weight, preferably from 2% to 8% by weight and better still from 2.5% to 7.5%) by weight of C₂-C₆ polyol(s) relative to the total weight of the composition.

Preferably, the plasticizing system (C) of a composition according to the invention may advantageously comprise a C₂-C₅ polyalkylene glycol(s)/C₂-C₆ polyol(s) weight ratio of between 0.05 and 0.5 and preferably between 0.1 and 0.3.

A proportionality relationship has also been observed between the content of photo-crosslinkable compound(s) (A) and the plasticizing system (C).

Advantageously, a composition according to the invention combines at least one photo-crosslinkable compound (A) and a plasticizing system (C) as defined above in a photo-crosslinkable compound(s) (A)/plasticizing system (C) weight ratio of between 0.1 and 0.5 and preferably between 0.15 and 0.4.

Adhering to such a weight ratio makes it possible to further improve the properties of the film resulting from the photo-crosslinking of a composition according to the invention in terms of resistance to deformation and of reversible mechanical properties. COMPOSITION ACCORDING TO THE INVENTION

As outlined above, a composition according to the invention is cosmetic and is intended for topical application. It consequently comprises a physiologically acceptable medium. For the purposes of the present invention, the term "physiologically acceptable medium" means a medium that is compatible with keratin materials such as the skin, the lips, mucous membranes, the eyelashes, the hair, the eyebrows and the nails, especially the skin.

As emerges from the foregoing, a composition according to the invention comprises an aqueous phase formed totally or partly by water that may be provided by the formulation of the photo-crosslinkable compound(s) (A) and/or of the swollen particulate starch (B).

This aqueous phase may comprise, besides water, at least one water-miscible solvent such as alcohols. The alcohols may be chosen from Ci-C₆ lower alkanols and preferably chosen from ethanol, propanol and isopropanol.

The aqueous phase may be present in a composition according to the invention in a content ranging from 2% to 99.9% by weight, especially from 5% to 98% by weight, preferably ranging from 10% to 97% by weight and better still from 75% to 96% by weight relative to the total weight of the composition. A composition according to the invention may be in various galenical forms normally used in cosmetics.

Thus, it may be in the form of an aqueous or aqueous-alcoholic solution, preferably in the form of an aqueous solution, of a dispersion of the lotion or serum type, of a gel, of a liquid emulsion obtained by dispersing a fatty phase in an aqueous phase (O/W) or conversely (W/O), of a suspension or emulsion of soft consistency or of a microemulsion, preferably a liquid emulsion obtained by dispersing a fatty phase in an aqueous phase (O/W). These compositions are prepared according to the usual methods known to those skilled in the art.

These compositions can advantageously constitute in particular creams for the face, for the hands or for the body, body milks, lotions, gels or foams, masks or also patches.

The compositions which can be used according to the invention can also be packaged in the form of an aerosol composition also comprising a pressurized propellant.

According to a particular embodiment, a composition of the invention may advantageously be in the form of a makeup base composition.

A composition of this type may be in the form of a face and/or body care or makeup product, and may be conditioned, for example, in the form of cream in a jar or of fluid in a tube or in a pump-action bottle.

According to another embodiment, a composition of the invention may advantageously be in the form of a foundation.

Such compositions are especially prepared according to the general knowledge of a person skilled in the art.

A composition according to the invention is more particularly intended to be applied to the skin of the face, the neck and the hands, but may also be applied to the body, the hair or the nails.

In point of fact, a composition according to the invention is applied as a coat onto the support under consideration, especially a keratin material as described above. The thickness of said coat is that commonly considered by users with a standard cosmetic composition. In particular, a composition according to the invention, when applied to a keratin material, may have a thickness of between 50 nm and 100 μιη.

A composition according to the invention may, of course, comprise a large number of the components conventionally considered in the galenical formulation, provided that these compounds do not impair the formation of the film by crosslinking or the desired properties of this film.

Thus, a composition according to the invention may comprise at least one fatty phase, especially comprising oils, gums or waxes usually used in the cosmetic or dermatological field.

Such a composition may also contain adjuvants (also known as additive(s) (D)) that are common in the cosmetic field, such as hydrophilic or lipophilic gelling agents, thickeners, preserving agents, antioxidants, solvents, fragrances, fillers, pigments, dyes, odour absorbers, pH agents and active agents. As mentioned previously, a composition according to the invention and more particularly the film derived therefrom also proves to be advantageous for conveying a certain number of compounds for which it is sought to perpetuate the efficacy on the keratin material at the surface of which the film is formed.

Thus, a composition according to the invention may also advantageously comprise at least one additive (D), chosen in particular from cosmetic active agents; natural or mineral, modified or unmodified pigments; fillers; dyes and polysaccharides; and mixtures thereof.

Advantageously, a composition according to the invention may comprise from 0.01% to 40% by weight, preferably from 0.1% to 30% by weight and in particular from 1% to 10% by weight of additive(s) (D) relative to the total weight of the composition.

Depending on their nature, these additives may be introduced into the fatty phase or into the aqueous phase. In any case, these additives, and the proportions thereof, will be chosen so as not to harm the desired properties of a composition according to the invention, and especially the qualities of the crosslinked film obtained after photo-crosslinking a composition according to the invention.

Cosmetic active agents

As indicated above, an additive (D) within the meaning of the present invention may especially be a cosmetic active agent. As cosmetic active agents that are suitable for use in the present invention, mention may be made especially of:

- antiageing/antiwrinkle agents,

- moisturizers,

- anti-pollution agents and/or free-radical scavengers, - agents acting on the capillary circulation,

- agents acting on the energy metabolism of cells,

- hyaluronic acid,

- antiglycation agents,

- NO-synthase inhibitors, - agents for stimulating the synthesis of dermal or epidermal macromolecules and/or for preventing their degradation,

- agents for stimulating fibroblast and/or keratinocyte proliferation or for stimulating keratinocyte differentiation,

- muscle relaxants (dermo -relaxing agents and/or dermo-decontracting agents), - tensioning agents,

- desquamating agents,

- depigmenting or propigmenting agents,

- anti-seborrhoea and anti- . acnes active agents,

- antioxidants and free-radical scavengers, - calmatives, and

- mixtures thereof.

The amount of cosmetic active agent(s) obviously depends on the nature of the active agent and on the desired effect, but said active agent(s) generally represent from 0.01% to 10%, or even from 0.1% to 5%, or even from 0.001% to 30% of the total weight of the composition. Advantageously, it is a cosmetic active agent such as, for example, a moisturizer, an anti-wrinkle active agent, a tensioning agent or a free-radical scavenger.

Advantageously, it is a cosmetic filler that affords optical effects (for example a soft-focus, matt or luminous effect) and/or colour effects. According to another of its aspects, the present invention relates to a composition, especially a cosmetic composition, for topical application, comprising, in a physiologically acceptable medium:

(A) at least one photo-crosslinkable compound as defined above;

(B) particulate starch in swollen form as defined above; (C) at least one plasticizing system as defined above; and

(D) at least one additive represented by a hyaluronic acid or a fragment thereof.

The "photo-crosslinkable compound(s) (A)/hyaluronic acid or a fragment thereof weight ratio may be between 0.01 and 3 and preferably between 0.05 and 1.5.

According to the invention, the hyaluronic acid preferably has a number- average molecular weight ranging from 500 Da to 10 MDa and more particularly ranging from 2 KDa to 2 MDa.

According to the invention, a hyaluronic acid fragment preferably has a number-average molecular weight ranging from 500 Da to 10 MDa and more particularly ranging from 20 KDa to 2 MDa. It may also be advantageously considered in the context of the invention a hyaluronic acid salt. Among the hyaluronic acid salts, mention may be made especially of the sodium salts, the potassium salts, the zinc salts and the silver salts, and mixtures thereof.

More particularly, as hyaluronic acid salts, mention may be made of potassium hyaluronate and sodium hyaluronate, preferably sodium hyaluronate. Preferably, as hyaluronic acid that is suitable for use in the present invention, mention may be made of those sold under the name Restylane^® by Laboratoire Q-Med, under the name Surgiderm^® by Laboratoire Corneal, and the hyaluronic acid fragments sold by the company Soliance. CROSSLINKED FILM

As indicated previously, a composition according to the invention is intended to form a crosslinked film, especially a cosmetic film, in particular for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails.

This film is obtained by photochemical crosslinking resulting from exposure to UV, especially to natural or artificial light, of a composition according to the invention, as detailed below.

A crosslinked film according to the invention preferably has a thickness of between 50 nm and 100 μιη, preferably between 25 nm and 50 μιη. A film according to the invention is advantageous, especially, in that it is highly water-resistant. On the other hand, and as emerges from the examples below, a film according to the invention may, however, be removed by cleansing with a conventional makeup remover.

UV EXPOSURE

A composition according to the invention, for producing a crosslinked film, requires at least one step of exposure of all or part of the surface of the coat resulting from the application of a composition according to the invention to conditions that are suitable for the crosslinking of the photo-crosslinkable compound (A), and thus of the composition according to the invention comprising it.

It falls to a person skilled in the art to select suitable exposure conditions, especially with regard to the nature of the photo-crosslinkable compound(s) (A) used in the composition. This exposure may consist of illumination, with ambient light or with a source of artificial light, of the surface of said coat.

The ambient or artificial light may emit radiation in the visible and/or UV range. Preferably, it emits at least a proportion of radiation in the UV range, for example a UV proportion of at least 2% of the total illuminating energy of the ambient light.

According to a particular embodiment, the exposure comprises, or even consists of, illumination with ambient light of the surface of said coat, in particular for a time of at least 1 minute.

The exposure time to the ambient light may range more particularly from 10 seconds to 30 minutes and especially from 2 to 15 minutes.

According to another particular embodiment, the exposure comprises, or even consists of, illumination with a source of artificial light of the surface of said coat.

The exposure time to said artificial light may range from 10 seconds to 20 minutes and in particular from 30 seconds to 10 minutes.

The crosslinking may take place with natural or artificial light, for example using lighting with a lamp, a flash, a laser or LEDs, for example in the form of an LED array.

The artificial light source may emit radiation in the visible range and/or radiation in the UV range.

The light emitted may or may not be monochromatic. The wavelength of the emitted light is preferably centred on 365 nm, in particular between 400 nm and 700 nm and better still between 365 nm and 550 nm.

Advantageously, the crosslinking is initiated by simple illumination without the need for a photoinitiator. Preferably, it will be a source of artificial light emitting energy of at least 0.2 mW/cm², in particular from 0.5 to 20 mW/cm², the exposure times being adapted in consequence.

The crosslinking may take place with a reduced light intensity: the lighting system may produce, for example, light intensity of less than 50 mJ/cm² or even 10 J/cm².

The twofold characteristic of the absence of a photoinitiator and the relatively low light intensity is particularly advantageous since it makes it possible to limit the harmful effects of aggressive initiators or of prolonged exposure to intense light, in particular in the UV wavelengths. A person skilled in the art will be capable of adapting the illumination characteristics, especially in terms of exposure time and of radiation wavelengths, with regard to the nature of the photo-crosslinkable compound(s) (A) used.

PROCESSES

The prolonged persistence over time of an immediate makeup and/or care effect of at least one particular compound, which is precisely the objective desired in the present invention, may be characterized by two different embodiment variants.

The first embodiment variant is characterized by the application of a single composition according to the invention, in which case said composition according to the invention already comprises the compound(s) intended to afford the desired immediate makeup and/or care effect.

The second embodiment variant is characterized by placing the composition according to the invention in contact with an associated composition whose effect, for example a makeup effect, it is desired to perpetuate.

This placing in contact may be performed according to two embodiments. According to a first embodiment, extemporaneous mixing, i.e. just before application, of the two compositions is performed. To this end, doses of each of the two compositions and a single-use form may be proposed to the user to ensure the production of the expected film at the surface of the targeted keratin material.

According to a second embodiment, the two compositions are placed in contact at the surface of the keratin material to be treated. The composition according to the invention is applied to a keratin material already coated with the associated composition and especially comprising at least the compound(s) intended to afford the desired immediate makeup and/or care effect.

The processes and uses described below follow from the foregoing.

The present invention thus relates to a cosmetic process for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, comprising at least the steps consisting in:

(i) applying at the surface of said keratin material a coat of at least one composition according to the invention as defined above; and

(ii) exposing all or part of the surface of the coat formed in step (i) to conditions suitable for photochemical crosslinking to form a crosslinked film at the surface of said keratin material.

The present invention also relates to a cosmetic process for improving the persistence over time, especially over a duration of greater than 4 hours, preferably greater than 8 hours, the adhesion to the keratin material and the resistance to water and to mechanical constraints (friction) of a cosmetic composition, especially for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, said process comprising at least the steps consisting in:

(i) extemporaneously incorporating into said cosmetic composition:

(A) at least one photo-crosslinkable compound as defined above; (B) particulate starch in swollen form as defined above; and

(C) at least one plasticizing system as defined above; and

(ii) applying at the surface of said keratin material a coat of the mixture obtained in step (i); and (iii) exposing all or part of this surface to conditions suitable for photochemical crosslinking to form a crosslinked film at the surface of said keratin material.

Preferably, compounds (A) to (C) are incorporated into the cosmetic composition in the form of a mixture, preferably a predosed mixture. The present invention also relates to the use of a composition according to the present invention for forming a film at the surface of a keratin material coated beforehand with a separate cosmetic composition.

The present invention also relates to a cosmetic process for improving the persistence over time, especially over a duration of greater than 4 hours, preferably greater than 8 hours, and the resistance to water and to mechanical constraints (friction), of a first cosmetic composition, especially a makeup and/or care composition, applied beforehand to the surface of a keratin material, in particular the skin, the lips, the hair and/or the nails, said process comprising at least the steps consisting in:

(i) covering said first cosmetic composition applied beforehand to the surface of a keratin material with a coat of at least a second composition according to the present invention; and

(ii) exposing all or part of the surface of the coat formed in step (i) to conditions suitable for photochemical crosslinking of said second composition to form a crosslinked film at the surface of said first composition. Needless to say, in all the processes according to the invention, the conditions that are suitable for photochemical crosslinking of a composition according to the invention to form a crosslinked film at the surface of a keratin material relate to those described above.

The present invention also relates to a kit for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, comprising at least:

- a first composition intended to afford a makeup and/or care effect on a keratin material, especially the skin, the lips, the hair and/or the nails, - a second composition according to the present invention, different from the first composition; and

Throughout the description, including the claims, the expression "comprising a" should be understood as being synonymous with "comprising at least one", unless otherwise specified. The terms "between... and..." and "ranging from... to..." should be understood as being inclusive of the limits, unless otherwise specified.

The examples that follow are presented as non-limiting illustrations of the invention.

EXAMPLES: Example 1: evaluation of compositions according to the invention in terms of deformations, mechanical strength and adhesion

The six compositions below according to the invention are prepared according to the protocol defined below.

Photo-

Swollen

crosslinkable Polyethylene

particulate

Composition compound Glycerol glycol" Water starch (B)^*

according to (A)*** (weight in weight % (in weight

Weight%

the invention Weight% %) (weight% of %)

(weight % of

(weight% of active material)

active material)

1 30 (3.2) 40 (2) 7.5 15 (1.5) qs 100

2 25 (2.7) 40 (2) 6.25 12.5 (1.25) qs 100

3 20 (2.2) 40 (2) 5 10 (1) qs 100

4 15 (1.6) 40 (2) 3.75 7.5 (0.75) qs 100

5 10 (1.1) 40 (2) 2.5 5 (0.5) qs 100

6 5 (0.5) 40 (2) 2.5 5 (0.5) qs 100

* Particulate starch in swollen form = corn starch (content of amylopectin/amylose: 70/30%) sold by the company Roquette, resulting from a preliminary step of heating for 6 hours at 100°C (i.e. aqueous solution containing 5% by weight of active material).

** Compound sold under the name Polyglycol-400 by the company Clariant (i.e. aqueous solution containing 10% by weight of active material).

*** PVA-SbQ sold under the reference Emulsion AD-V5-10 Fl PB by the company Murakami Protocol for preparing the compositions:

The compositions were prepared by homogenization of all the components described in the above table with mechanical stirring for 10 minutes, at room temperature in containers allowing the composition to be kept from ambient light.

For each composition above, a coat is applied onto a neutral support of Skin FX type (silicone-based support 80 mm in diameter, covered with a polyurethane film). This coat, especially in terms of thickness, is similar to a coat resulting from the conventional application of a composition by a user. Each coat is then exposed to UV light (UVA (7 mW/cm²) + UVB (2.5 mW/cm²)) for 10 minutes (= 5.7 J/cm²).

Complete crosslinking of the coat of the test composition was controlled visually and sensorily. This is reflected especially by the absence of a highlight zone and by a dry feel.

Results

All the formulations tested lead, after spreading onto a Skin FX support and photo-crosslinking under UV, to the formation of a very elastic (up to 150% deformation) and strong film.

In particular, no deformation is observed after stretching, irrespective of the direction of the stress (manual stretching of the Skin FX support up to 150% deformation). In other words, return to the initial state is observed after the stress is stopped. In addition, no formation of pilling is observed after rubbing the film formed (friction by hand by performing about 20 rubbing actions on the film).

In addition, the films obtained are transparent, very matt and all have very good properties of adhesion to the Skin FX support.

The above results were also observed after 5-10 minutes (depending on the content of PVA-SbQ) of exposure to natural light, even with a low level of sunlight.

The above results were also observed by replacing the PVA-SbQ Emulsion AD-V5-10 Fl PB with PVA-SbQ Emulsion AD-V5 Fl PB sold by Murakami.

Example 2: evaluation of a composition according to the invention in terms of resistance to water and to friction

Example 2 was performed using composition 3 described in Example 1, the only difference being that the composition of Example 2 also comprises a mineral pigment as compound having an immediate makeup effect. Three tests were performed, each with composition 3 of Example 1 also comprising a mineral pigment in a content of 1%. For each test, the pigment under consideration is, respectively, (i) Metashine MT1030PS (Nippon Sheet Glass), (ii) Metashine MT1030GP (Nippon Sheet Glass) and (iii) Cosmetic Metallic Powder Visionaire Olive Gold (Eckart).

For each test, a control was performed in parallel. This control consists in applying to the Skin FX support a coat of a dispersion of the pigment in water at the same content as in the composition containing the photo-crosslinkable compound. The deposit thus formed was left to dry for 24 hours at room temperature. All the protocols and parameters considered for obtaining and depositing said composition on the Skin FX support, and similarly the step of UV illumination to obtain a crosslinked film, are identical to those described in Example 1 above.

For each test, the two Skin FX supports (i.e. test with composition according to the invention and associated control) were then immersed in a bath of water (film-covered support dipped in 400 mL of water at room temperature) for 40 minutes, so as to evaluate visually the quality of the deposit obtained, especially the pigment residue, after this immersion.

In addition, for each test, the two Skin FX supports (i.e. test with composition according to the invention and associated control) were reproduced and immersed in a bath of water (400 mL of water at room temperature) for 40 minutes and using a magnetic stirrer so as to simulate frictions (use of a 70 mm magnetic bar deposited on the support, with a stirring speed of 200 rpm). Finally, the Skin FX supports (i.e. test with composition according to the invention and associated control) resulting from the step of immersion in water accompanied by stirring underwent a step of cleaning with a moist sponge (sponge used by beauticians for cleaning the face) followed by rinsing with warm water (about 30°C) for 20 seconds.

Results

The distribution of pigment is markedly more homogeneous when it was introduced into formulation 3 according to the invention. Moreover, the addition of pigment has no influence on the elastic properties and the resistance to friction of the film resulting from the photo-crosslinking of the test compositions according to the invention.

After 40 minutes in the water bath, the control deposit (pigment alone) was completely removed by the water, whereas the film according to the invention containing pigment shows no degradation. In particular, no presence of pigment in the water bath was observed, this being the case for the three different types of pigments considered.

After 40 minutes in the water bath and using a magnetic stirrer, the films according to the invention were only slightly damaged and thus appear very resistant to water and to mechanical stresses, for instance friction or rubbing. It is even observed that these films are even strong enough to withstand the abovementioned cleaning step.

It is pointed out, however, that the films according to the invention can be removed by cleansing with a makeup remover for removing waterproof makeup, for example with the product Demaquillant Yeux Waterproof Respectissime from La Roche Posay. In summary, a composition according to the invention leads, after photo- crosslinking, to the production of a crosslinked film that is highly resistant to water and to friction and is thus capable of significantly improving the persistence over time of a technology with an immediate makeup or care effect included in said composition according to the invention, while at the same time having very satisfactory elastic deformation properties.

Example 3: evaluation of a composition according to the invention with respect to a deposit based on hyaluronic acid fragments (HAF)

The immediate effects of hyaluronic acid fragments (HAF) on the complexion and the visibility of the pores are known, as is rapid impairment over time of these properties. In addition, a deposit of hyaluronic acid fragments is glossy, sparingly water-resistant and, above a critical concentration of HAF, leads to the formation of a very rigid film which may cause the user discomfort. A coat of a solution of hyaluronic acid fragments (120 kDa) (1% starting material) was applied to a Skin FX support. This coat, especially in terms of thickness, is similar to a coat resulting from the conventional application of a composition by a user.

After total evaporation of the water present in the applied solution (24 hours of drying at room temperature), a coat of composition 5 described in Example 1 above is applied onto the coat of said HAF-based solution.

All the protocols and parameters considered for obtaining and depositing said composition on the Skin FX support, and similarly the step of UV illumination to obtain a crosslinked film, are identical to those described in Example 1 above. Results

The composition according to the invention leads, after photo-crosslinking, to the production of a crosslinked film that is highly resistant to water and to friction and significantly improves the persistence over time of the makeup effect afforded by the composition previously applied containing the hyaluronic acid fragments, while at the same time having very satisfactory elastic deformation properties.

Moreover, the film obtained is satisfactory in terms of gloss.

Example 3 thus demonstrates the possibility of improving the immediate makeup and/or care effects of a compound applied beforehand or, in other words, when said compound is coated with a composition according to the invention. Example 4: evaluation of a composition according to the invention also comprising hyaluronic acid (HAF) as additive

The six compositions below according to the invention were prepared. They especially comprise hyaluronic acid fragments (HAF) (120 kDa) identical to those described in Example 3 above. Photo-

Swollen

crosslinkable Polyethylene

particulate HARDf"

Composition compound glycol^**

starch (B)^* Glycerol Weight% according to Weight%

Weight% Weight% (in weight% of the invention Weight% (in weight% of

(weight% of active material) (weight% of active material)

active material)

7 5 (0.5) 30 (1.5) 10 17.5 (1.75) 37.5 (9.4)

8 10 (1.1) 30 (1.5) 10 17.5 (1.75) 32.5 (8.1)

9 15 (1.6) 30 (1.5) 10 17.5 (1.75) 27.5 (6.9)

10 20 (2.2) 30 (1.5) 10 17.5 (1.75) 22.5 (5.6)

11) 25 (2.7) 30 (1.5) 10 17.5 (1.75) 17.5 (4.4)

12 30 (3.2) 30 (1.5) 10 17.5 (1.75) 12.5 (3.1)

Compounds *, ** and ***: see Example 1.

**** Hyaluronic acid fragments (120 kDa) sold under the name Hyactive by the company Soliance (at 25% by weight of active material).

All the protocols and parameters considered for obtaining and depositing each composition according to the invention tested on the Skin FX support, and similarly the step of UV illumination to obtain a crosslinked film, are identical to those described in Example 1 above.

Results

The compositions according to the invention all lead, after photo-crosslinking, to the production of a crosslinked film that is highly resistant to water and to friction and thus significantly improves the persistence over time of the hyaluronic acid on the support, while at the same time having very satisfactory elastic deformation properties. Nearly all the crosslinked films are moreover satisfactory in terms of gloss (sparingly glossy). The films obtained with compositions 7 and 8 are slightly glossy due to the higher contents of hyaluronic acid fragments.

All the films tested also show good adhesion to the skin. Example 4 thus demonstrates the possibility of improving the immediate makeup and/or care effects of a compound when it is used in a composition according to the invention.

Claims

1. Composition, especially a cosmetic composition, for topical application, comprising, in a physiologically acceptable medium: (A) at least one photo-crosslinkable compound comprising at least one activated photo-dimerizable group bearing at least one activated double bond;

(B) particulate starch in swollen form; and

(C) at least one plasticizing system comprising at least one C₂-C5 polyalkylene glycol and at least one C₂-C6 polyol other than a polyalkylene glycol.

2. Composition according to the preceding claim, characterized in that the photo-crosslinkable compound (A) bears one or more functions that are cyclizable in a 2/2 reaction and that are sensitive to light irradiation in the absence of a photoinitiator and/or of a chemical initiator.

3. Composition according to Claim 1 or 2, in which said activated photo-dimerizable group is chosen from: a) photo-dimerizable groups bearing a stilbazolium function of formula (la) or (lb) below:

in which:

- R' represents a hydrogen atom or a C₁-C₄ alkyl group, and

- X^" denotes an ion chosen from chloride, bromide, iodide, perchlorate, tetrafluoroborate, methyl sulfate, phosphate, sulfate, methanesulfonate and p-toluenesulfonate ions;

in which:

- R' ' denotes a divalent alkylene radical containing from 2 to 8 carbon atoms,

- R' represents a hydrogen atom or a C₁-C₄ alkyl group, and

in which:

- X- has the same meaning as that described for the preceding formula (la).

4. Composition according to any one of the preceding claims, characterized in that the photo-crosslinkable compound (A) is a polyvinyl alcohol (PVA) partly functionalized with one or more hydroxyl functions and one or more functions of formula (III):

5. Composition according to any one of the preceding claims, characterized in that said composition comprises from 0.1% to 5% by weight and preferably from 0.5% to 3.5%) by weight of photo-crosslinkable compound(s) (A) relative to the total weight of the composition.

6. Composition according to any one of the preceding claims, characterized in that the particulate starch in swollen form (B) or a precursor thereof is/are chosen from:

- native starches chosen from corn starch, rice starch, cassava starch, tapioca starch, barley starch, potato starch, wheat starch, sorghum starch and pea starch, where appropriate modified by one or more reactions chosen from pregelatinization, degradation, especially acid hydrolysis, oxidation or dextrinization, substitution, especially esterification or etherification, crosslinking, especially esterification, bleaching or hydrophobization;

- starches grafted with an acrylic polymer (homopolymer or copolymer), and especially with sodium polyacrylate;

- hydro lyzed starches grafted with an acrylic polymer (homopolymer or copolymer), and especially with acryloacrylamide/sodium acrylate copolymer;

- polymers based on starch, gum and cellulose derivative, preferably (d-C₄) carboxyalkyl starches; - starches grafted with at least one C1 -C4 carboxyalkyl group on at least one alcohol function of the starch; and - mixtures thereof.

7. Composition according to any one of the preceding claims, characterized in that said composition comprises from 0.1% to 10% by weight, preferably from 0.5% to 5% by weight, preferably from 1% to 3% by weight of solids of swollen particulate starch (B) relative to the total weight of the composition.

8. Composition according to any one of the preceding claims, characterized in that the C2-C5 polyalkylene glycol is chosen from polyethylene glycol, polypropylene glycol and polybutylene glycol, and mixtures thereof, preferably polyethylene glycol.

9. Composition according to any one of the preceding claims, characterized in that said composition comprises from 0.1% to 3% by weight, preferably from 0.25% to

2% by weight and better still from 0.5%> to 1.75% by weight of C2-C5 polyalkylene glycol(s) relative to the total weight of the composition.

10. Composition according to any one of the preceding claims, characterized in that the C2-C6 polyol is chosen from pentaerythritol, trimethylolpropane, propylene glycol, 1,3-propanediol, butylene glycol, isoprene glycol, pentylene glycol, hexylene glycol, glycerol, 1,5-pentanediol, dipropylene glycol, diglycerol, xylitol and stereoisomers thereof, sorbitol and stereoisomers thereof, and inositol and stereoisomers thereof, and mixtures thereof, preferably glycerol.

11. Composition according to any one of the preceding claims, characterized in that said composition comprises from 0.1% to 20% by weight, preferably from 2% to

8%) by weight and better still from 2.5% to 7.5% by weight of C2-C6 polyol(s) relative to the total weight of the composition.

12. Composition according to any one of the preceding claims, characterized in that the plasticizing system (C) of said composition comprises a C2-C5 polyalkylene glycol(s)/C2-C₆ polyol(s) weight ratio of between 0.05 and 0.5 and preferably between 0.1 and 0.3.

13. Composition according to any one of the preceding claims, characterized in that said composition comprises a photo-crosslinkable compound(s) (A)/plasticizing system (C) weight ratio of between 0.1 and 0.5 and preferably between 0.15 and 0.4.

14. Composition according to any one of the preceding claims, characterized in that said composition also comprises at least one additive (D), preferably chosen from a polysaccharide; pigments; fillers; dyes; a cosmetic active agent; and mixtures thereof.

15. Composition according to the preceding claim, characterized in that the additive (D) is a polysaccharide represented by hyaluronic acid or a fragment thereof.

16. Composition according to Claim 14 or 15, characterized in that said composition comprises from 0.01% to 40%> by weight, preferably from 0.1 % to 30%> by weight and in particular from 1% to 10% by weight of additive(s) (D) relative to the total weight of the composition.

17. Composition according to any one of the preceding claims, characterized in that it is free of photoinitiator and/or of chemical initiator.

18. Crosslinked film, especially a cosmetic film, for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, obtained by photochemical crosslinking with natural or artificial light of a composition according to any one of the preceding claims.

19. Cosmetic process for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, comprising at least the steps consisting in:

(i) applying at the surface of said keratin material a coat of at least one composition as defined according to any one of Claims 1 to 17; and

20. Cosmetic process for improving the persistence over time, especially over a duration of greater than 4 hours, preferably greater than 8 hours, the adhesion to a keratin material and the resistance to water and to mechanical constraints (friction) of a cosmetic composition, especially for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, said process comprising at least the steps consisting in: (i) extemporaneously incorporating into said cosmetic composition:

(A) at least one photo-crosslinkable compound according to Claims 1 to 5;

(B) particulate starch in swollen form according to Claims 1, 6 and 7; and

(C) at least one plasticizing system according to Claims 1 and 8 to 13;

21. Cosmetic process according to the preceding claim, characterized in that compounds (A) to (C) are incorporated into the cosmetic composition in the form of a mixture, preferably a predosed mixture.

22. Cosmetic process according to Claim 20 or 21, characterized in that the cosmetic composition comprises at least one additive (D), preferably chosen from a polysaccharide; pigments; fillers; dyes; a cosmetic active agent; and mixtures thereof.

23. Use of a composition according to any one of Claims 1 to 17, for forming a film at the surface of a keratin material already coated with a separate cosmetic composition.

24. Cosmetic process for improving the persistence over time, especially over a duration of greater than 4 hours, preferably greater than 8 hours, and the resistance to water and to mechanical constraints (friction), of a first cosmetic composition, especially a makeup and/or care composition, applied beforehand to the surface of a keratin material, in particular the skin, the lips, the hair and/or the nails, said process comprising at least the steps consisting in: (i) covering said first cosmetic composition applied beforehand to the surface of a keratin material with a coat of at least a second composition as defined according to any one of Claims 1 to 17; and

(ii) exposing all or part of the surface of the coat formed in step (i) to conditions suitable for photochemical crosslinking of said second composition to form a crosslinked film at the surface of said first composition.

25. Kit for making up and/or caring for a keratin material, in particular the skin, the lips, the hair and/or the nails, comprising at least:

- a second composition, different from the first composition, and as defined according to any one of Claims 1 to 17; and

- optionally, at least one member intended for the mixing and/or sequential or extemporaneous application of said first and second compositions to the surface of said keratin material .

26. Care and/or makeup kit according to the preceding claim, characterized in that each of the first and second compositions is in a single-use dose form.