Antioxidant cosmetic composition

Abstract

The invention relates to an antioxidant cosmetic composition comprising water, at least 3 different polyols including glycerin, 1,3-propanediol at a concentration greater than or equal to 1% and less than 6.5% by weight relative to the total weight of the composition, and at least one other polyol, at least one ascorbic acid derivative, at least one absorbent agent at a concentration greater than 3% by weight relative to the total weight of the composition, at least one gelling agent, said composition being free of oily emollients. Another object of the invention is directed to the cosmetic use of this composition in order to protect the skin, preferably oily skin, against damage caused by free radicals.

Description

[0001] ANTIOXIDANT COSMETIC COMPOSITION The invention relates to a new antioxidant cosmetic composition, specifically formulated to overcome the limitations of existing compositions containing vitamin C (ascorbic acid).

[0002] TECHNICAL CONTEXT

[0003] In the field of cosmetics, vitamin C is widely recognized for its skin-regenerating properties, thanks to its antioxidant effects. However, the use of ascorbic acid or its derivatives at concentrations above 1% by weight in aqueous formulations presents significant challenges. Indeed, at these concentrations, ascorbic acid becomes unstable, leading to color changes and a degradation of its beneficial properties, thus limiting its effectiveness as an active ingredient. To overcome these problems, several alternatives have been proposed in the prior art. Among these are kits in which ascorbic acid is presented in powder form, requiring immediate solubilization in a solution before use. Other formulations utilize encapsulation of ascorbic acid to improve its stability.Derivatives of ascorbic acid, such as ascorbyl glucoside, have also been proposed due to their improved stability. However, these solutions can still be improved in terms of efficacy.

[0004] Furthermore, sensory appeal is now a key factor for consumers, who are particularly drawn to light, easily spreadable, and non-sticky textures. Therefore, there is a constant need to develop new antioxidant formulations that combine efficacy, stability, and an advantageous sensory profile. In particular, a fluid, light, and non-sticky texture that spreads easily is highly sought after.

[0005] A more specific need for the care of oily skin must also be considered. This involves reducing or even avoiding the addition of oily ingredients that could give the skin extra shine. On the contrary, it is desirable to mattify the skin while maintaining the best possible antioxidant efficacy and formulation stability, without compromising the desired sensory profile. The invention therefore aims to meet these challenges by offering an innovative antioxidant cosmetic composition, based on an ascorbic acid derivative, capable of satisfying the growing demands of consumers in terms of performance and sensory experience. This includes acceptable stickiness upon application, even on oily skin, and no oily feeling, as well as no sensation of tightness or dryness, no soaping required, easy application, and rapid absorption by the skin.The invention further aims to ensure that the composition contains as few ingredients as possible, and that the results are obtained without increasing its cost price, and without the need to incorporate controversial substances.

[0006] DESCRIPTION OF THE INVENTION

[0007] It has been discovered by the present inventors that such objectives are achieved by implementing an aqueous composition comprising an ascorbic acid derivative such as ascorbyl glucoside, a specific combination of polyols, an absorbent agent and a gelling agent; said composition being devoid of oily emollients.

[0008] Thus, according to a first aspect of the invention, an antioxidant cosmetic composition is proposed comprising:

[0009] - water, in a concentration greater than or equal to 70% by weight relative to the total weight of the composition,

[0010] - at least 3 distinct polyols including:

[0011] • glycerin,

[0012] • 1,3-propanediol in a concentration greater than or equal to 1% and less than 6.5% by weight relative to the total weight of the composition,

[0013] • and at least one other polyol,

[0014] the total concentration of polyols being between 10 and 20% by weight relative to the total weight of the composition,

[0015] - at least one ascorbic acid derivative selected from ascorbyl glucoside, sodium ascorbyl phosphate, magnesium ascorbyl phosphate and mixtures thereof,

[0016] - at least one sebum-absorbing agent in a concentration greater than 3% by weight relative to the total weight of the composition,

[0017] - and at least one gelling agent, the said composition being devoid of oily emollients and devoid of emulsifying agents.

[0018] By "at least one" is meant, in this description, a single compound or a mixture of several such compounds.

[0019] According to the present invention, "free of" an ingredient means that the composition does not contain that ingredient, or contains it in a trace, non-functional amount, preferably less than 0.1% by weight, preferably less than 0.05% by weight, and preferably even less than 0.01% by weight, relative to the total weight of the composition.

[0020] The antioxidant cosmetic composition of the invention is intended for topical application.

[0021] For the purposes of this invention, "topical application" means application to the skin (including the scalp) and mucous membranes, preferably the skin.

[0022] The antioxidant cosmetic composition of the invention is preferably applied to healthy skin, and is particularly suitable for oily skin.

[0023] The cosmetic composition according to the invention comprises at least 70% by weight of water relative to the total weight of the composition.

[0024] In a particular embodiment of the invention, the water concentration in the antioxidant cosmetic composition is between 70 and 85% by weight, or between 70 and 80% by weight, relative to the total weight of the composition. POLYOLS

[0025] The term "polyol" (also called polyalcohol) is classically understood to mean a compound comprising a hydrocarbon chain with at least two carbon atoms and at least two hydroxyl groups. The polyol(s) contained in the cosmetic composition according to the invention may be natural or synthetic. They may have a linear, branched, or cyclic molecular structure, preferably linear or branched, and more preferably linear.

[0026] One of the essential features of the invention is that the composition comprises at least three distinct polyols, including glycerin, 1,3-propanediol, and at least one other polyol, that is, at least one polyol other than glycerin and 1,3-propanediol. Preferably, the at least one other polyol is chosen from glycols other than 1,3-propanediol, and preferably from propylene glycol, dipropylene glycol, butylene glycol, pentylene glycol, hexylene glycol, caprylyl glycol, and mixtures thereof.

[0027] In preferred embodiments of the invention, said at least one other polyol, preferably each of said other polyols, contained in the composition is of the humectant type.

[0028] In a preferred embodiment of the invention, at least one other polyol is pentylene glycol. The composition thus comprises at least the following 3 polyols, and preferably only the following 3 polyols: glycerin, 1,3-propanediol and pentylene glycol.

[0029] In another embodiment of the invention, the composition comprises at least the following 4 polyols, and preferably only the following 4 polyols: glycerin, 1,3-propanediol, pentylene glycol and another polyol selected from propylene glycol, dipropylene glycol, butylene glycol, hexylene glycol, caprylyl glycol.

[0030] The composition may also include at least the following 4 polyols, and preferably only the following 4 polyols: glycerin, 1,3-propanediol, pentylene glycol and caprylyl glycol.

[0031] In general, the composition according to the invention preferably contains the fewest possible polyols. Thus, in particular embodiments of the invention, the composition comprises no more than 6 polyols, preferably no more than 5 polyols, preferably even no more than 4 polyols, and preferably contains only 3 polyols. As indicated above, each of these polyols preferably has humectant properties.

[0032] 1,3-Propanediol is present in the composition in an amount greater than or equal to 1% and less than 6.5% by weight, preferably in an amount between 2% and 6% by weight, relative to the total weight of the composition. In a particular embodiment of the invention, the amount of 1,3-propanediol is 5% by weight relative to the total weight of the composition.

[0033] Advantageously, the amount of glycerin in the composition according to the invention is between 1% and 15% by weight, preferably between 2% and 10% by weight, even more preferably between 3% and 8% by weight, relative to the total weight of the composition.

[0034] In a particular embodiment of the invention, the total amount of polyol(s) other than glycerin and 1,3-propanediol in the composition according to the invention is between 1% and 10% by weight, preferably between 2% and 8% by weight, even more preferably between 3% and 6% by weight, relative to the total weight of the composition.

[0035] The total concentration of polyols in the composition according to the invention is preferably between 10% and 15% by weight, relative to the total weight of the composition.

[0036] ASCORBIC ACID DERIVATIVE

[0037] The composition according to the invention comprises at least one ascorbic acid derivative selected from ascorbyl glucoside, sodium ascorbyl phosphate, magnesium ascorbyl phosphate, and mixtures thereof. In a preferred embodiment of the invention, the at least one ascorbic acid derivative is ascorbyl glucoside.

[0038] The total concentration of ascorbic acid derivative(s) is preferably between 0.5% and 5% by weight, more preferably between 1% and 3% by weight, relative to the total weight of the composition.

[0039] ABSORBENT AGENT

[0040] The cosmetic composition according to the invention comprises at least one sebum-absorbing agent, which notably allows for the removal of excess sebum from the skin.

[0041] In this description, the term "sebum-absorbing agent" (or "absorbing agent") refers to a cosmetic ingredient, preferably in the form of a water-dispersible powder, whose main function is to remove excess sebum from the skin and help to give the skin a matte appearance, when applied topically. The at least one sebum-absorbing agent used in the composition according to the invention is thus of the type capable of absorbing oily liquids.

[0042] The at least one absorbent agent contained in the cosmetic composition according to the invention is preferably chosen from: starches, starch derivatives, cellulose, microcrystalline cellulose, clays, calcium carbonate, silica, talc and mixtures thereof.

[0043] Preferably, the absorbent agent is chosen from starches and starch derivatives. The starches may be derived from a plant source such as cereals, tubers, roots, vegetables, and fruits. Examples include rice starch, corn starch, potato starch, pea starch, oat starch, barley starch, tapioca starch, wheat starch, or sorghum starch. The starches may be modified or unmodified. A modified starch is a starch that has been altered by processes known to those skilled in the art, such as esterification, etherification, oxidation, acid hydrolysis, cross-linking, or enzymatic conversion. Preferably, at least one starch in the antioxidant cosmetic composition according to the invention is unmodified. The composition preferably comprises only unmodified starches of plant origin.

[0044] In embodiments of the invention, an absorbent agent is a clay selected from kaolin, bentonite, montmorillonite, green clay, red clay, pink clay, white clay, and yellow clay. Preferably, the absorbent agent is kaolin and / or bentonite; preferably kaolin.

[0045] According to particular embodiments of the invention, the cosmetic composition according to the invention contains at least one absorbent agent other than silica. Silica is relatively controversial for use in cosmetics, particularly due to the negative environmental impact associated with its production.

[0046] The total concentration of absorbent agent(s) in the composition according to the invention is greater than 3% by weight, and preferably less than or equal to 8% by weight, more preferably between 3.5% and 7% by weight, and even more preferably between 4% and 6% by weight, relative to the total weight of the composition. In a particular embodiment of the invention, the total concentration of absorbent agent(s) is between 4% and 5% by weight relative to the total weight of the composition.

[0047] Preferably, the total concentration of absorbent agent(s) selected from starches, starch derivatives, cellulose, microcrystalline cellulose, clays, calcium carbonate, silica, talc and mixtures thereof, is greater than 3% by weight, and preferably less than or equal to 8% by weight, more preferably between 3.5 and 7% by weight, more preferably between 4 and 6% by weight, for example between 4 and 5% by weight, relative to the total weight of the composition.

[0048] Preferably, the total concentration of absorbent agent(s) selected from starches, starch derivatives, cellulose, microcrystalline cellulose, clays, calcium carbonate, talc and mixtures thereof, is greater than 3% by weight, and preferably less than or equal to 8% by weight, more preferably between 3.5 and 7% by weight, more preferably between 4 and 6% by weight, for example between 4 and 5% by weight, relative to the total weight of the composition; the composition then being preferably free of silica.

[0049] Such a high total concentration of absorbent agent(s) does not, in particular, compromise the desired fluidity of the composition. The presence of powders not only provides particularly beneficial absorbent properties for oily skin but can also give the composition an opacity similar to the appearance of a conventional emulsion; the difference being that there is no oil phase in the compositions according to the invention.

[0050] In general, the composition according to the invention preferably contains the fewest absorbent agents possible. Thus, in particular embodiments of the invention, the composition comprises no more than 4 absorbent agents, preferably no more than 3 absorbent agents, preferably still no more than 2 absorbent agents, and preferably contains only 1 absorbent agent.

[0051] GELDING AGENT

[0052] The cosmetic composition according to the invention comprises at least one gelling agent.

[0053] In this description, the term "gelling agent" refers to a cosmetic ingredient, preferably water-soluble or water-dispersible, more preferably water-soluble, whose main function is to modify the texture and viscosity of the composition, thus enabling a pleasant and easy-to-apply consistency. The sebum-absorbing agents used in the composition according to the invention, although they may also affect the composition's texture, are primarily chosen for their absorbent and mattifying properties. The gelling agent, on the other hand, is specifically selected for its thickening and stabilizing properties. Within the scope of the present invention, at least one gelling agent contained in the composition is distinct from the sebum-absorbing agent(s) contained therein.Thus, preferably, at least one gelling agent contained in the composition is of the hydrophilic type, not capable of absorbing sebum.

[0054] The at least one gelling agent contained in the cosmetic composition according to the invention is preferably chosen from: gums such as xanthan gum, scleroglucan gum, succinoglucan gum, gellan gum, diutan gum, acacia gum, guar gum, Caesalpinia spinosa gum, locust bean gum, Tamarindus indica seed gum; pectin; carrageenans and their derivatives; acrylates and their derivatives; alginates and their derivatives; cellulose derivatives such as carboxymethyl cellulose or hydroxypropyl methyl cellulose; and any mixture thereof.

[0055] Any non-microplastic acrylate and / or derivatives of non-microplastic acrylates can be used according to the invention. In preferred embodiments of the invention, acrylates and their derivatives that can be used in the composition according to the invention, alone or in any of their mixtures, correspond to the following INCI names: Acrylates / C 10-30 Alkyl Acrylate Crosspolymer, Acrylates / vinyl isodecanoate crosspolymer, Sodium Polyacrylate, Hydroxyethyl Acrylate / Sodium Acryloyldimethyl Taurate Copolymer, Acrylates Copolymer, Polyacrylate-13, Polyacrylamide, Ammonium Acryloyldimethyltaurate / VP Copolymer.Hydroxyethyl Acrylate / Sodium Acryloyldimethyl Taurate Copolymer, Sodium Acrylate / Acryloyldimethyltaurate / Dimethylacrylamide Crosspolymer, Carbomer, Polyphosphorylcholine Glycol Acrylate, Acrylates / Ethylhexyl Acrylate Copolymer, Glyceryl Acrylate / Acrylic Acid Copolymer, Sodium Acrylate / Sodium Acryloyldimethyl Taurate Copolymer, Butyl Acrylate / Isobornyl Methacrylate Copolymer, Poly C10-30 Alkyl Acrylate. The term "microplastic" as used in the present invention refers to microparticles of synthetic polymers and corresponds to the definition given in the regulation published on September 27, 2023, "Commission Regulation (EU) 2023 / 2055 of September 25, 2023, amending Annex XVII to Regulation (EC) No 1907 / 2006." of the European Parliament and of the Council concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH), as regards synthetic polymer microparticles.According to this document, microplastics, or microparticles of synthetic polymers, are defined as polymers that are solid and that either are contained within particles and constitute at least 1% by weight of these particles, or form a continuous surface coating on particles, when at least 1% by weight of these particles fulfill one of the following conditions: (a) all dimensions of the particles are less than or equal to 5 mm; (b) the length of the particles is less than or equal to 15 mm and their length-to-diameter ratio is greater than 3.The following polymers are excluded from this designation: (a) polymers resulting from a polymerization process that has occurred in nature, which are not chemically modified substances; (b) polymers that are degradable as proven in accordance with Annex 15 of the document; (c) polymers that have a solubility greater than 2 g / L as proven in accordance with Annex 16 of the document (water solubility test at pH 7 under stirring for 24 h at 20°C, with a polymer loading of 10 g / 1000 mL, according to the protocol of Test No. 120 or Test No. 105 of the OECD Guidelines for the Testing of Chemicals); (d) polymers that do not contain carbon atoms in their chemical structure. Synthetic polymer microparticles covered by the derogation provided for in point 4a of the said draft amendment to Annex XVII are also excluded from this definition.

[0056] More generally, microplastics can be defined as particles with all dimensions less than 5 mm, formed or coated with solid synthetic organic polymer(s) that are insoluble in water and non-biodegradable. Any alginate and / or alginate derivatives can be used according to the invention. In preferred embodiments of the invention, alginates and their derivatives that can be used in the composition according to the invention, alone or in any of their mixtures, have the following INCI names: Algin, sodium alginate, potassium alginate, propylene glycol alginate. Any carrageenan and / or carrageenan derivatives can be used according to the invention.In preferred embodiments of the invention, carrageenans and their derivatives that can be used in the composition according to the invention, alone or in any of their mixtures, correspond to the following INCI names: carrageenan, sodium carrageenan.

[0057] In preferred embodiments of the invention, cellulose derivatives that can be used in the composition according to the invention, alone or in any of their mixtures, correspond to the following INCI names: carboxymethyl cellulose (often referred to by INCI as "cellulose gum"), sodium carboxymethyl cellulose (a salt of carboxymethyl cellulose, also often referred to by INCI as "cellulose gum"), ethyl cellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropyl methylcellulose, cetyl hydroxyethylcellulose.

[0058] The total concentration of gelling agent(s) in the composition according to the invention is preferably between 0.1 and 1.5% by weight, preferably between 0.2 and 1% by weight, and more preferably between 0.3 and 0.8% by weight, relative to the total weight of the composition.

[0059] In general, the composition according to the invention preferably contains the fewest possible gelling agents. Thus, in particular embodiments of the invention, the composition comprises no more than 4 gelling agents, preferably no more than 3 gelling agents, preferably still no more than 2 gelling agents, and preferably contains only 1 gelling agent.

[0060] OILY EMOLLIENTS

[0061] Another essential feature of the invention is that the antioxidant cosmetic composition is free of oily emollients.

[0062] In this description, the term "oily emollient" refers to an oily cosmetic ingredient whose main function is to moisturize and soften the epidermis when applied topically. "Oily" is defined as an organic compound insoluble in water at 25°C, 1 atm, i.e., with a water solubility of less than 5% by weight, preferably less than 1% by weight.

[0063] Examples include the following oily emollients, the composition of which according to the invention is devoid of:

[0064] - triglycerides. Triglycerides are composed of three fatty acids linked by ester bond to a glycerol molecule. Triglycerides excluded from the composition according to the invention include, in particular, triglycerides esterified by C8-C18 fatty acids, in particular by C10-C18 fatty acids, and more particularly caprylic / capric acid triglycerides;

[0065] - non-hydrogenated vegetable oils, such as sunflower, corn, olive, sweet almond, coconut, palm, safflower, soybean, pumpkin, grapeseed, sesame, hazelnut, apricot, macadamia, avocado, jojoba, borage, rapeseed, wheat germ, flaxseed, evening primrose, argan, calendula, cottonseed;

[0066] - solid fats having a melting point of less than or equal to 45°C, preferably strictly less than 45°C, such as butters, for example shea butter;

[0067] - synthetic esters and ethers, particularly of fatty acids, such as oils with formulas R1COOR2 and R1OR2, in which Ri represents the remainder of a fatty acid containing 8 to 29 carbon atoms, and R2 represents a hydrocarbon chain, branched or unbranched, containing 3 to 30 carbon atoms, such as Purcellin oil, isononyl isononanoate, isopropyl myristate, ethylhexyl palmitate, octyl-2-dodecyl stearate, octyl-2-dodecyl erucate, isostearyl isostearate;Hydroxylated esters such as isostearyl lactate, octyl hydroxystearate, octyldodecyl hydroxystearate, diisostearyl malate, triisocetyl citrate, heptanoates, octanoates or decanoates of fatty alcohols, polyol esters such as propylene glycol dioctanoate, neopentyl glycol diheptanoate and diethylene glycol diisononanoate, and pentaerythritol esters such as pentaerythrityl tetraisostearate or dipentaerythrityl pentaisononanoate; - and mixtures thereof. More generally, the composition according to the invention is preferably free of fatty substances.

[0068] In a preferred embodiment, the antioxidant cosmetic composition according to the invention is formulated to have a pH between 5 and 7, preferably between 5.5 and 6.3. This pH range, close to the natural pH of the skin, aims to provide skin-friendly, stable, and effective compositions that are also particularly suitable for oily skin. Conventionally, the pH of the composition according to the invention can be adjusted by adding appropriate quantities of acids and / or bases well known to those skilled in the art, such as citric acid and sodium hydroxide.

[0069] The antioxidant cosmetic composition according to the invention is preferably a leave-on composition, that is, a composition that does not require rinsing, particularly with water, as opposed to aqueous solutions containing surfactants or any other cleansing ingredient. The composition of the invention is intended to be left on the skin after application. Furthermore, it is particularly intended for application on oily skin.

[0070] The composition according to the invention does not contain an emulsifying agent and preferably does not contain a surfactant either, and is in no way an emulsion; the composition according to the invention is also not a two-phase water / powder composition. On the contrary, it is formulated to be a homogeneous solution in which the ingredients are well dispersed and stabilized, without any visible phase separation. This homogeneity ensures uniform application and consistent product efficacy.

[0071] The aqueous composition according to the invention is thus free of emulsifying agents, more particularly of any emulsifier conventionally used in cosmetic emulsions for skin care, typically oil-in-water (O / W) or water-in-oil (W / W) emulsions. In particular, it is free of emulsifying agents selected from the group consisting of hydrogenated or non-hydrogenated lecithins; glyceryl stearate; glyceryl stearate citrate; polysorbates 20, 40, 60, 80; sorbitan esters including sorbitan olivate, sorbitan laurate, sorbitan monostearate, sorbitan palmitate; and PEG-n stearates. emulsifying waxes including glucoside waxes, alkyl glucosides, ethoxylated fatty alcohols, sodium stearoyl lactylate, polyethylene glycol stearates and sucrose esters including sucrose stearate, polyglyceryl esters of fatty acids, potassium cetyl phosphate, sodium stearoyl glutamate, sodium stearoyl lactylate, etc.

[0072] In particular embodiments of the invention, the antioxidant cosmetic composition further comprises one or more additional active skin-care agents, for example, selected from niacinamide, glutamic acid, zinc gluconate, glyceryl laurate, resveratrol, and / or panthenol; it preferably comprises at least niacinamide. In particular embodiments, the cosmetic composition according to the invention may further comprise an extract of Lens esculenta seed, this species being commonly known as green lentil. This extract is preferably obtained by aqueous extraction. It preferably contains, or is essentially composed of, an oligosaccharide fraction, in particular composed mainly of oligosaccharides of the trehalose, maltose, maltotriose, stachyose, and verbascose type.In particular embodiments of the invention, the Lens esculenta seed extract contains 20% to 40% by weight, in particular 25% to 35% by weight, of said oligosaccharide fraction, relative to the total weight of the extract (in the dry state).

[0073] The total amount of Lens esculenta seed extract in the cosmetic composition according to the invention is typically between 0.025% and 0.2% by weight, in particular between 0.025% and 0.15% by weight and, in particular, between 0.025% and 0.10% by weight, relative to the total weight of the composition.

[0074] In some embodiments, the composition includes hyaluronic acid or one of its salts, preferably sodium hyaluronate, as an additional active agent.

[0075] In other embodiments of the invention, the composition is devoid of hyaluronic acid or one of its salts.

[0076] The cosmetic composition according to the invention may further contain one or more monoalcohols, such as ethanol.

[0077] In other embodiments, the cosmetic composition according to the invention may be free of monoalcohols such as ethanol. The composition according to the invention is preferably free of silicone. For the purposes of the present invention, silicone, or polysiloxane, conventionally means any organosilicon polymer or oligomer with a linear and / or cyclic, branched and / or cross-linked structure, obtained by polymerization and / or polycondensation of functionalized silanes, and consisting essentially of a repetition of principal motifs in which silicon atoms are linked together by oxygen atoms, with hydrocarbon radicals, possibly substituted, in particular by hydroxyl groups, being directly linked by a carbon atom to these silicon atoms.

[0078] The cosmetic composition according to the invention is also preferably free of phenoxyethanol, which is suspected of being an endocrine disruptor. It is preferably also free of parabens.

[0079] The composition according to the invention can be manufactured using any process known to a person skilled in the art. The composition according to the invention can, for example, be in the form of a serum, a lotion, or a gel.

[0080] The antioxidant activity obtained with a composition according to the present invention is beneficial as such or as a complement to action in several cosmetic indications, as it helps to protect the skin against damage caused by free radicals, which are involved, for example, in premature skin aging.

[0081] Another aspect of the invention relates to the non-therapeutic cosmetic use of a composition according to the invention, preferably in its embodiments containing an additional active agent for skin care, as described above, to protect the skin, preferably oily skin, against damage caused by free radicals.

[0082] In various embodiments of the invention, the composition according to the present invention can be used for one of the following indications: - as an anti-aging product for the reduction of wrinkles and fine lines. Antioxidants help to neutralize free radicals, thus reducing oxidative damage that contributes to the formation of wrinkles and fine lines;

[0083] - for improving skin elasticity: by protecting collagen and elastin fibers, antioxidants help maintain skin firmness and elasticity;

[0084] - to fight against pigment spots: antioxidants can help reduce hyperpigmentation by inhibiting melanin production;

[0085] - to complement sun protection against UV radiation: antioxidants can complement the action of UV filters by neutralizing free radicals generated by sun exposure, thus reducing photo-induced damage;

[0086] - to protect against environmental aggressions: antioxidants protect the skin against pollutants and other environmental aggressions that can exacerbate skin sensitivity.

[0087] The antioxidant cosmetic composition according to the invention is preferably intended to be applied to the skin, preferably healthy skin and preferably oily skin, this application not being followed by a rinsing step.

[0088] The invention also relates to a non-therapeutic cosmetic process for protecting the skin, preferably oily skin, against damage caused by free radicals, particularly for combating skin aging, specifically reducing wrinkles and fine lines, improving skin elasticity, protecting it against environmental aggressors, and / or enhancing the sun protection effect of UV filters. This process comprises the topical application to the skin, preferably healthy, preferably oily skin, of an antioxidant cosmetic composition according to the invention, in an effective quantity to achieve the desired protective effect. It does not require rinsing.

[0089] The features and advantages of the invention will become more apparent in the light of the following implementation examples, provided for illustrative purposes only and in no way limiting the invention.

[0090] EXAMPLES

[0091] 1 / Example 1: Sensory test

[0092] The aim of this study is to compare the general (visual observation) and sensory characteristics of different compositions. These are evaluated by a person trained in sensory techniques for cosmetic products, in order to determine whether their sensory profile is satisfactory; more specifically, regarding the criteria of stickiness, fluidity, and any other sensation that could be detrimental to the desired sensory experience, as well as stability.

[0093] The different compositions tested are detailed in Table 1 (the values ​​indicated are % by weight relative to the weight of the composition): the composition according to the invention is composition A; comparative compositions 1 and 2 include contents of 1,3-propanediol and / or absorbent agent (starch powder) outside the claimed ranges.

[0094]

[0095] Table 1 - Tested compositions

[0096] The protocol was as follows: 60 µl of each composition was applied to the anterior surface of the evaluator's previously cleaned forearm. The evaluation was performed 5 minutes after application. The room temperature and humidity were monitored, and the lighting was controlled during this experiment.

[0097] The results obtained are presented in Table 2 below.

[0098]

[0099] Table 2 - Results

[0100] It was observed that comparative compositions 1 and 2 induce a feeling of tightness in the skin, experienced as discomfort. Furthermore, the evaluator also perceived their skin as drier. Finally, composition 1 is visually uneven.

[0101] Thus, compositions 1 and 2 are evaluated as not conforming to the invention.

[0102] Only composition A exhibits a good visual appearance, good fluidity, no sticky effect, no oily feel, and no discomfort felt on the skin 5 minutes after application. This composition A, according to the invention, provides the desired sensory experience.

[0103] These results demonstrate the importance of the 1,3-propanediol content associated with the absorbent agent.

[0104] 2 / Example 2: Evaluation of the antioxidant efficacy of different compositions. The aim of this study is to evaluate the antioxidant efficacy of a composition according to the invention. To do this, the production of free radicals is quantified and compared to a formula containing ascorbic acid instead of ascorbyl glucoside.

[0105] Fragments of skin (recovered after plastic surgeries) are fractionated into pieces of approximately 1.5 cm 2These pieces are placed in culture plates (Corning USA) in a specific culture medium and are maintained at 37°C in an incubator with 5% CO2.

[0106] The skin fragments are treated once with the application of a composition to be tested at a rate of 25-30 mg / cm² 2 , then are kept in culture for 2 days. For each group, there are 6 skin fragments, n=6.

[0107] After incubation, the skin samples are subjected to a dose of 15 J / cm² 2 Ultraviolet (UV) radiation was used with the UVACube 400, SOL 500 H2 (Hoenle UV America Inc., MA, USA). Cultures were incubated for 24 hours. Fragments were then collected for labeling and semi-quantification of synthesized free radicals.

[0108] Semi-quantification of free radical synthesis is performed using the DCFH-DA probe.

[0109] Skin fragments were embedded in Tissue-Tek® and 12 µm histological sections were prepared using a cryostat (Leica®, GER-CRYOCUT 1800). The sections were then washed with phosphate buffer and incubated for 1 minute with a 1:10,000 solution of dichlorodihydrofluorescein diacetate (DCFH-DA; Sigma, USA). The intensity of the fluorescence emitted by the oxidation of the DCFH-DA probe was analyzed under a microscope (OLYMPUS, JAP-BX53) using CellSens software (2010 OLYMPUS CORPORATION).

[0110] After obtaining the images, the intensity of the fluorescence is quantified using Image J software (version 1.48, in Arbitrary Units).

[0111] For statistical evaluation, the ANOVA test was used to measure the variation in results by comparing the results between groups. The Bonferroni post-test was then applied to strengthen and refine the results. A significance level of 5% was used.

[0112] The tested compositions are described below:

[0113] 1 / Composition according to the invention: composition A as described in Table 1 of Example 1,

[0114] - 2 / Comparative compositions:

[0115] Composition 3 is identical to composition A, except that ascorbyl glucoside is replaced by 22% by weight of L-ascorbic acid relative to the composition's weight. This difference of more than 20% is compensated for by the presence of a lower quantity of water in composition 3. Composition 4 contains 15% L-ascorbic acid and also includes the following ingredients (INCI names): AQUA • DIPROPYLENE GLYCOL • ASCORBIC ACID • GLYCERIN • LAURETH-23 • PHENOXYETHANOL • TOCOPHEROL • FERULIC ACID • SODIUM HYALURONATE.

[0116] The results are presented in Table 3 below. As expected, UV exposure led to a very significant increase in free radical production (+472%), p<0.001, compared to the unexposed group. UV radiation clearly induced oxidative stress.

[0117] < < <

[0118]

[0119] Table 3 - Results of the antioxidant efficacy assessment - AU: Arbitrary Unit; UV: ultraviolet; vs: versus

[0120] Composition A (according to the invention) drastically reduces the production of free radicals (more than 78% reduction, P<0.001).

[0121] Composition 3, which is similar to composition A but contains ascorbic acid instead of ascorbyl glucoside, does not show a significant reduction in free radical production, the protective effect being very moderate (20.3% reduction).

[0122] Comparative composition 4, very different in its ingredients, shows significant antioxidant activity (p<0.01 vs UV group), but the reduction in free radical production is only 29%.

[0123] A statistical difference in terms of effectiveness is even identified between composition 4 and the composition according to the invention (p=0.0439).

[0124] The composition according to the invention thus appears truly promising in terms of antioxidant activity. Indeed, applying a composition according to the invention effectively reduces oxidative stress in the skin, exerting a protective effect against the excessive increase in free radical synthesis induced by UV exposure. This result is all the more convincing when compared to a composition with a very high vitamin C content (over 20% by weight). It demonstrates the high stability of the ascorbic acid derivative in the composition according to the invention, even under the conditions of its very high water content.

[0125] 3 / Example 3: Comparative sensory test

[0126] In this example, a composition B conforming to the invention is compared to a comparative composition not conforming to the invention (composition 5) having a formula similar to that of composition B but a total polyol content greater than 20% by weight.

[0127] The formula for these compositions is given in Table 4 below.

[0128]

[0129] Table 4 - Formulas of composition B according to the invention and comparative composition 5

[0130] The protocol is identical to the sensory test performed in example 1. The evaluation was carried out during application and 5 minutes after application.

[0131] Different criteria are evaluated and are detailed in Table 5.

[0132]

[0133] Table 5 - Sensory evaluation criteria

[0134] The results obtained are shown in Table 6:

[0135]

[0136] Table 6 - Sensory evaluation test results - "0" = no effect; "+" = satisfactory; "-" = unsatisfactory

[0137] During application, greater lathering is observed with comparative composition 5, which contains a higher concentration of polyols (all humectants). This composition 5 is also absorbed more slowly.

[0138] On the other hand, composition B according to the invention not only does not have these disadvantages but also spreads more easily, and makes it possible to overcome the tension effect also felt after the application of the comparative composition.

[0139] Thus, only composition B according to the invention is compliant and provides the desired sensory experience.

[0140] These results demonstrate the importance of the total polyol content being between 10 and 20% by weight in the composition according to the invention.

Claims

DEMANDS 1. Antioxidant cosmetic composition comprising: - water in a concentration greater than or equal to 70% by weight relative to the total weight of the composition, - at least 3 distinct polyols including: • glycerin, • 1,3-propanediol in a concentration greater than or equal to 1% and less than 6.5% by weight relative to the total weight of the composition, • and at least one other polyol, the total concentration of polyols being between 10 and 20% by weight relative to the total weight of the composition, - at least one ascorbic acid derivative selected from ascorbyl glucoside, sodium ascorbyl phosphate, magnesium ascorbyl phosphate and mixtures thereof, - at least one sebum-absorbing agent in a concentration greater than 3% by weight relative to the total weight of the composition, - and at least one gelling agent, said composition being devoid of oily emollients and devoid of emulsifying agents.

2. Composition according to claim 1, characterized in that the total concentration of polyols is between 10% and 15% by weight, relative to the total weight of the composition.

3. Composition according to any one of claims 1 or 2, characterized in that at least one other polyol is selected from propylene glycol, dipropylene glycol, butylene glycol, pentylene glycol, hexylene glycol, caprylyl glycol and mixtures thereof.

4. Composition according to claim 3, characterized in that at least one other polyol is pentylene glycol.

5. Composition according to any one of claims 1 to 4, characterized in that at least one sebum-absorbing agent is selected from starches, starch derivatives, cellulose, microcrystalline cellulose, clays, calcium carbonate, silica, talc and mixtures thereof.

6. Composition according to any one of claims 1 to 5, characterized in that the total concentration of sebum-absorbing agent(s) is greater than 3% by weight and less than or equal to 8% by weight relative to the total weight of the composition.

7. Composition according to any one of claims 1 to 6, characterized in that at least one derivative of ascorbic acid is ascorbyl glucoside.

8. Composition according to any one of claims 1 to 7, characterized in that the total concentration of ascorbic acid derivative(s) is between 0.5 and 5%, preferably between 1% and 3%, by weight relative to the total weight of the composition.

9. Composition according to any one of claims 1 to 8, characterized in that at least one gelling agent is selected from xanthan gum, scleroglucan gum, succinoglucan gum, gellan gum, diutan gum, acacia gum, guar gum, Caesalpinia spinosa gum, locust bean gum, Tamarindus indica seed gum; pectin; carrageenans and their derivatives; acrylates and their derivatives; alginates and their derivatives; cellulose derivatives such as carboxymethyl cellulose or hydroxypropyl methyl cellulose; and any mixture thereof.

10. Composition according to any one of claims 1 to 9, characterized in that the total concentration of gelling agent(s) is between 0.1 and 1.5%, preferably between 0.2 and 1%, more preferably between 0.3% and 0.8%, by weight relative to the total weight of the composition.

11. Composition according to any one of claims 1 to 10, characterized in that the water concentration is between 70 and 85%, by weight relative to the total weight of the composition.

12. Composition according to any one of claims 1 to 11, characterized in that the composition further comprises niacinamide, glutamic acid, zinc gluconate, glyceryl laurate, resveratrol and / or panthenol; preferably at least niacinamide.

13. Non-therapeutic cosmetic use of a composition according to any one of claims 1 to 12 to protect the skin, preferably oily skin, against damage caused by free radicals.

14. Non-therapeutic cosmetic process for protecting the skin, preferably oily skin, against damage caused by free radicals, comprising the topical application to the skin of a composition according to any one of claims 1 to 12.

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