Aqueous composition for the preparation of a peelable mask

Abstract

The invention relates to an aqueous composition for preparing a peelable, non-therapeutic cosmetic mask comprising two separate mixtures brought into contact upon application to an individual. The invention also relates to a cosmetic treatment method using said composition, a kit for preparing a peelable mask, and a method for preparing the aqueous composition.

Description

Title of the invention: Aqueous composition for the preparation of a peelable mask

[0001] The invention relates to an aqueous composition for preparing a peelable, non-therapeutic cosmetic mask comprising two separate mixtures brought into contact upon application to an individual. The invention also relates to a cosmetic treatment method using said composition, a kit for preparing a peelable mask, and a method for preparing the aqueous composition.

[0002] The invention is in the field of cosmetics and dermatology. It finds a particularly advantageous application in the field of skin care. Prior Art

[0003] Topical application products such as masks are well known in the cosmetic and dermatological fields. They are presented in particular in the form of impregnated fabrics, or emulsions, gels or pastes, which are removed by wiping or peeling.

[0004] During the application time, the occlusive effect of the mask allows the stratum corneum to hydrate and soften, which can promote the penetration of substances having biological or pharmacological activity, in the case where one or more active substances are included in the composition.

[0005] Various mask formulas are described in the literature, for example in "Cosmetic and Toiletry Formulations", Second Edition, Ernest W. Flick 1992.

[0006] Masks in the form of emulsions, gels or pastes, which are removed by wiping, may have the disadvantage of having to be removed at the end of the application time at the cost of sometimes tedious manipulations, such as wiping and washing the skin; especially since the composition of the mask has been studied to strengthen its adhesion to the skin.

[0007] Impregnated masks do not present this drawback, since they rely on the use of a support, textile or otherwise, thus allowing the mask to be removed in a simple operation. However, to be effective, the support of impregnated masks must perfectly conform to the contours and shape of the body part to be treated, which limits their application possibilities compared to cream-based masks.

[0008] There are also aqueous film-forming compositions based on polyvinyl alcohol that form masks that peel off. These peel-off masks dry after application to the face to form a homogeneous plastic film with sufficient mechanical coherence to allow Remove the film by peeling it off without tearing it. These masks have the advantage of providing a good seal.

[0009] However, removing these masks can be harsh on the skin, making their use impractical. Furthermore, the presence of petrochemical compounds such as polyvinyl alcohol in their composition renders them unsuitable for natural formulations.

[0010] We also know of aqueous film-forming compositions based on water-soluble polymers of natural origin such as alginates which form masks that can be removed by peeling.

[0011] The advantages of topical alginates for promoting the skin penetration of substances with biological or pharmacological activity are known. Patent EP 0888769 describes several compositions using lyophilized alginates, whose moisturizing, nourishing, restructuring, and firming properties have been described.

[0012] Several patents also describe their use in compositions capable of forming homogeneous plastic films for topical application of the "peel-off" mask type.

[0013] In the latter case the formation of the homogeneous plastic film is obtained through the crosslinking reaction of an alkali alginate salt polymer by a source of calcium in solution in the ionic state Ca2+.

[0014] Patent EP0045493 describes such a composition for the preparation of a cosmetic mask, comprising an alginate, a divalent metal salt (calcium ion Ca2+), a phosphate, an anionic surfactant and a filler such as SiO2, or ZnO, or A12O3.

[0015] In this patent application, the crosslinking agent is incorporated into a dehydrated alginate composition. The dry form of the composition does not allow the crosslinking reaction, which must take place in an aqueous medium, to begin. A retarder (phosphate) provides the user with sufficient time to rehydrate the composition and apply it to the skin before the polymer crosslinks and the film forms.

[0016] Since the crosslinking agent (calcium ion Ca2+) is previously incorporated into the alginate mass, this solution has the advantage of leading to homogeneous crosslinking of the polymer mass, which leads to good mechanical strength of the film thus obtained.

[0017] However, the significant proportion of mineral substances in the composition, resulting from the need to incorporate a retarder, limits the crosslinking reaction of the alginate polymer. It is therefore necessary to apply the mask in a thick layer to obtain sufficient mechanical strength to allow the film to be peeled off in one application.

[0018] Furthermore, the need for a suitable container and the preparation time of the material by rehydrating the composition under agitation may limit the distribution of such a product to the general public.

[0019] Patent W0 2012095567 proposes an improvement by adding a powdered fluidifier to the composition to be rehydrated, facilitating the mixing of the dehydrated preparation with the water necessary for gel formation. However, this composition does not eliminate the need to rehydrate the composition before application.

[0020] Patent WO 1990002774 describes the crosslinking of a mask composed, among other things, of an aqueous sodium alginate gel by spraying a 10% aqueous solution of calcium chloride (CaC12) onto the surface of the alginate gel once applied to the skin.

[0021] Spraying an aqueous solution of CaC12 to cause the crosslinking of an aqueous gel composed of alkali metal alginate is advantageous because the film-forming preparation can then be rehydrated in advance and presented to the user in the form of a ready-to-use gel.

[0022] However, CaC12 solutions are irritating to the skin and eyes, requiring the user to close their eyes during spraying. This can compromise the proper distribution of the spray on the gel layer and limit the appeal of this solution to the public.

[0023] Moreover, since the diffusion of CaC12 through the alginate polymer layer is not homogeneous, the plastic film thus formed may lack mechanical coherence in places, which makes its removal tedious because the film breaks when it is removed and the removal must therefore be done in several stages.

[0024] Spraying other calcium salts less irritating to the eyes, such as a calcium lactate solution, was tested. However, the lower reactivity of calcium lactate makes the cross-linking of the alginate gel even less effective. Furthermore, the film obtained after cross-linking was found to be fragile and prone to tearing when peeled from the skin.

[0025] Furthermore, prior art rehydratable compositions must incorporate an alkaline-earth ion sequestering agent, generally a phosphate, to prevent untimely crosslinking of the gel during rehydration of the alginate and carbonate mixture, in order to give the user sufficient time to apply the mixture to the skin.

[0026] Thus, the need remains for a peelable occlusive mask that does not have the drawbacks of those of the prior art, and to date, no alginate-based topical composition exists that allows for the successive application of two mixtures one on top of the other by cross-linking the surface of the first. Furthermore, to date, no alginate-based topical composition exists that allows immediate application, without prior mixing of two components in a suitable container, or without rehydration of dehydrated powders.

[0027] Surprisingly, the Applicant has demonstrated a new composition for topical application, presented as two aqueous mixtures, usable by a single person, quickly and easily and without external assistance. Description of the invention

[0028] Thus, according to a first aspect, the invention relates to an aqueous composition for the preparation of a peelable, non-therapeutic cosmetic mask comprising: • A first mixture comprising: i. An alginate gel of at least one alkali metal; ii. At least one salt of an alkaline earth metal that is insoluble at basic or neutral pH; • A second mixture comprising: i. At least one soluble salt of an alkaline earth metal; ii. At least one acidifying compound.

[0029] The first aqueous mixture according to the invention comprises at least one alkaline compound, so as to avoid the solubilization of the salt of the metal used with the release of the corresponding alkaline earth ions, and the crosslinking of the alginate gel which would follow.

[0030] The inventors have discovered that in order to render the salt of an insoluble alkaline earth metal at basic or neutral pH inactive with respect to the crosslinking of alginate, it is advisable to maintain the pH of the first mixture at an optimal value between 8 and 9, preferably between 8.5 and 9. This is achieved by adding at least one alkalizing compound to the first mixture.

[0031] The second aqueous mixture according to the invention is maintained at acidic pH thanks to at least one acidifying compound.

[0032] This composition combines two aqueous mixtures forming a homogeneous and coherent plastic film when applied one after the other to the skin of an individual, said film being able to be removed without tearing by peeling.

[0033] Preferably, said alginate of at least one alkali metal is present in a concentration of between 0.5% and 10% by total weight of the composition of the first mixture, preferably between 2% and 4%, even more preferably 3%.

[0034] According to one embodiment, said alkali metal alginate is selected from sodium alginate, potassium alginate, or a mixture thereof.

[0035] Preferably, said alkali metal alginate gel is sodium alginate. Even more preferably, said sodium alginate is present in a concentration of between 0.5% and 10% by total weight of the composition of the first mixture, preferably between 2% and 4%, even more preferably 3%.

[0036] Even more preferably, said salt of an insoluble alkaline earth metal at basic or neutral pH is present in a concentration of between 0.1% and 5% by total weight of the composition of the first mixture, preferably between 0.2% and 2%, even more preferably 0.5%.

[0037] According to one embodiment, said salt of an insoluble alkaline earth metal at basic or neutral pH is chosen from calcium sulfate, calcium carbonate, or a mixture thereof.

[0038] Preferably, said salt of an insoluble alkaline earth metal at basic or neutral pH is calcium carbonate.

[0039] Even more preferably, said calcium carbonate is present in a concentration of between 0.1% and 5% by total weight of the composition of the first mixture, preferably between 0.2% and 2%, even more preferably 0.5%.

[0040] Preferably, the source of calcium carbonate is organic. Said organic source may be pearl powder or oyster shell powder.

[0041] Even more preferably, said oyster shell powder has a particle size between 0.1 and 500 qm, even more preferably between 0.01 and 30 qm.

[0042] Preferably, said first mixture comprises at least one alkalizing compound.

[0043] According to one embodiment, said alkalizing compound is selected from sodium hydroxide, potassium citrate, triethanolamine, or a mixture thereof.

[0044] The aforementioned presence of the "alkalizing compound" takes into account the possibility of varying the choice of components in the formula, and in particular the source of calcium. Alternatively, due to the nature of the ingredients, the formula already has a slightly alkaline pH, with calcium carbonate raising the pH above 8.

[0045] Said alkalizing compound is present in sufficient quantity to achieve the optimal pH condition for the proper functioning of the invention.

[0046] Preferably, said alkalizing compound is present in a concentration of between 0.1% and 5% by total weight of the composition of the first mixture, preferably between 0.5% and 2%.

[0047] According to one embodiment, the second mixture comprises between 0.5% and 10%, preferably between 2% and 7%, by weight of the second mixture of said soluble salt of an alkaline earth metal.

[0048] According to one embodiment, said soluble salt of an alkaline earth metal is selected from calcium chloride, calcium lactate, calcium gluconate or a mixture thereof.

[0049] Preferably, said acidifying compound is present between 0.1% and 10%, of preferably between 3.5 and 8.5%, even more preferably 6%, by weight of the second mixture.

[0050] According to one embodiment, said acidifying compound is selected from phytic acid, citric acid, malic acid, glycolic acid, gluconodeltalactone or a mixture thereof.

[0051] Preferably, said acidifying compound is a mixture of phytic acid and gluconolactone. Even more preferably, the second mixture comprises between 0.5% and 1.5%, preferably 1% by weight of the second mixture of phytic acid, and between 3% and 7%, preferably 5% by weight of the second mixture of gluconodeltalactone.

[0052] Said at least one acidifying compound makes it possible to dissociate said salt of an insoluble alkaline earth metal at basic or neutral pH from the first mixture and thus release Ca2+ ions into the first mixture, when the second mixture is applied to the first on the user's skin.

[0053] According to one embodiment, the two mixtures may comprise at least one preservative, preferably between 1% and 10% by weight of each of the mixtures.

[0054] According to one embodiment, the first mixture may also include water-soluble polymers.

[0055] The addition of certain polysaccharides to this mixture makes it possible to improve the mechanical coherence of the resulting plastic film.

[0056] Preferably, said polysaccharides are of natural origin.

[0057] Even more preferably, said polysaccharides are chosen from pullullan, carrageenans, gum arabic, guar gum, tara gum or one of their mixtures.

[0058] Even more preferably, said polysaccharides are present in a proportion ranging from 0.1% to 5%, preferably between 0.5% and 3%, even more preferably 1.4%, by weight of the first mixture.

[0059] According to one embodiment, the first mixture comprises a mixture of pullullan, gum arabic and carrageenan.

[0060] Preferably, this first mixture comprises 0.5% by weight of the first mixture of pullullan, 0.5% by weight of the first mixture of gum arabic and 0.4% by weight of the first mixture of carrageenan.

[0061] The addition of certain polyols to this mixture makes it possible to improve the plasticity of the resulting plastic film.

[0062] The plasticity and mechanical consistency characteristics of the film are important because they determine the ability of the plastic film to tear off in one piece without ripping.

[0063] Preferably, said polyol may be selected from erythritol, sorbitol, the mannitol, or xylitol, or one of their mixtures.

[0064] Even more preferably, said polyols are present in a proportion ranging from 0.1% to 10%, preferably between 0.5% and 5%, even more preferably 1%, by weight of the first mixture.

[0065] Even more preferably, said polyol is erythritol present at 1% of the total weight of the first mixture.

[0066] According to one embodiment, said first mixture may also include fillers, organic or mineral, intended to opacify the plastic film obtained by crosslinking the film-forming polymer.

[0067] Preferably, said fillers are opacifiers classically used in the field of topical cosmetic applications, such as titanium dioxide, rice starch, talc, kaolin, or one of their mixtures.

[0068] According to one embodiment, said fillers comprise a mixture of rice starch and kaolin, in equal parts, representing between 0.5 and 10%, preferably between 1% and 5%, even more preferably 4% of the total weight of the mixture 1.

[0069] According to one embodiment, mixture 1 may also include other cosmetically acceptable active compounds. Any active compound may be used in the invention provided that it is compatible with the hydrophilic film-forming polymer used in the first mixture, in particular sodium alginate.

[0070] Such active ingredients may include, in particular, the following categories of ingredients: vitamins, healing agents, anti-aging, anti-wrinkle, soothing, or antioxidant agents, free radical scavenging or anti-UV agents, agents stimulating the synthesis of dermal macromolecules or energy metabolism, moisturizing, antibacterial, antifungal, anti-inflammatory, anesthetic agents, agents modulating cell differentiation, skin pigmentation or depigmentation.

[0071] A person skilled in the art shall ensure that these active ingredients and their proportions are chosen in such a way as not to impair the advantageous properties of the composition according to the invention. The total proportion of these active ingredients may, for example, be between 0.01 and 10% of the total weight of the composition (of mixture 1 and / or mixture 2).

[0072] According to one embodiment, said aqueous composition for the preparation of a peelable non-therapeutic cosmetic mask comprises: • A first mixture comprising: i. Between 0.5% and 10% by weight of the first mixture of an alginate gel of at least one alkali metal; ii. Between 0.1% and 5% by weight of the first mixture of at least one salt of an insoluble alkaline earth metal at basic or neutral pH; iii. Between 0.1% and 5% by weight of the first mixture of at least one alkalizing compound; • A second mixture comprising: i. Between 0.5% and 10% by weight of the second mixture of at least one soluble salt of an alkaline earth metal; ii. Between 0.1% and 10% by weight of the second mixture of at least one acidifying compound.

[0073] According to one embodiment, an example of a first mixture is as follows (by weight of the first mixture): • Demineralized water: q.s. 100% • Sodium alginate: 3% • Carrageenan: 0.4% • Pullulane: 0.5% • Gum arabic: 0.5% • Erythritol: 1% • Rice starch: 3% • Clay: 0.5% • Kaolin: 0.5% • Calcium carbonate: 0.5% • Conservative

[0074] Embodiment without gelling agent

[0075] According to one embodiment, said second mixture does not include a gelling agent.

[0076] In this embodiment, the second mixture comprises, as a soluble salt of an alkaline earth metal, calcium chloride, between 0.5% and 10%, preferably between 3% and 7%, even more preferably 5%, by weight of the second mixture.

[0077] In one embodiment, the second mixture comprises calcium lactate, between 0.5% and 10%, preferably between 3% and 7%, even more preferably 5%, by weight of the second mixture.

[0078] According to one embodiment, an example of a second mixture according to this embodiment is as follows (by weight of the second mixture): • Demineralized water: q.s. 100% • Calcium lactate: 5% • Gluconodeltalactone: 5% • Phytic acid: 1% • Conservative

[0079] Gelling embodiment

[0080] According to an alternative embodiment, said second mixture comprises a gelling agent.

[0081] The addition of this gelling agent has the advantage of forming an aqueous gel with pseudo-gelling properties suitable plastics.

[0082] Preferably, said gelling agent is chosen from polymers of natural or synthetic origin.

[0083] Even more preferably, said polymers are chosen from: carboxyvinyl polymers resulting from the association of vinylic acid molecules, acrylic copolymers such as acrylate-alkylacrylate copolymers, polyacrylamides, cellulosic derivatives such as carboxymethylcellulose, possibly modified polysaccharides such as hydroxypropylcellulose, or polysaccharides from natural raw materials, such as carrageenans, guar gum, locust bean gum, scleroglucan, cellulose, dehydroxanthan gum, tara gum or xanthan gum, or a mixture thereof.

[0084] According to one embodiment, said gelling agent is a hydrophilic polymer having the property of forming an aqueous gel with suitable pseudo-plastic properties.

[0085] According to one embodiment, said gelling agent is Carbopol® or SynerGX®.

[0086] SynerGX® comprises guar gum and xanthan gum.

[0087] According to one embodiment, said gelling agent comprises SynerGX® and carrageenan. More preferably, the second mixture comprises 1.3% SynerGX® and 1.5% carrageenan.

[0088] Carbopol® comprises carboxyvinyl polymers.

[0089] In this embodiment, the second mixture comprises, as a soluble salt of an alkaline earth metal, calcium chloride, between 0.5% and 10%, preferably between 2% and 5%, by weight of the second mixture.

[0090] In one embodiment, the second mixture comprises calcium lactate, between 0.5% and 10%, preferably between 3% and 7%, even more preferably 5%, by weight of the second mixture.

[0091] According to one embodiment, an example of a second mixture according to this embodiment is as follows (by weight of the second mixture): • Demineralized water: q.s. 100% • Calcium lactate: 5% • Carrageenan: 0.5% • SynerGX® (Guar Gum and Xanthan Gum): 1% • Gluconodeltalactone: 5% • Phytic acid: 1% • Conservative

[0092] According to a second aspect, the invention relates to a non-therapeutic cosmetic skincare method for an individual, comprising the application of an aqueous composition according to the invention in order to obtain a peelable mask, via the successive steps of: • Application of the first mixture to the skin of the said individual; • Application of the first mixture applied to the skin of said individual second mixture.

[0093] Preferably, the individual's skin is the skin of the face.

[0094] According to one embodiment, when the second mixture does not include a gelling agent, this second mixture can be applied by spraying.

[0095] Successive application in a thin layer on the skin has the property of forming a coherent plastic film, thanks to a simple and easily adjustable process, without the use of toxic or irritating substances.

[0096] The two mixtures are applied successively, one on top of the other, to the skin and then form a coherent and homogeneous plastic film, which can be easily removed by peeling, or "peel-off" effect.

[0097] Thanks to the characteristics of the composition according to the invention, this application method allows a single person to apply the mask according to the invention to the skin, more particularly to the face, easily and without outside help.

[0098] According to one embodiment, the first mixture is applied to the individual's skin with the fingers, or using an appropriate utensil (brush or spatula) in order to form a uniform layer of gel with a thickness of a few tenths (a few millimeters) on the skin.

[0099] Preferably, the second mixture is applied without waiting after application of the first mixture, on the layer of the first mixture previously applied to the face of the individual.

[0100] Thanks to the characteristics of the composition according to the invention, the application of the second mixture on the layer of the first mixture, with fingers or with any other application utensil such as a spatula or a brush, does not destroy the layer of the first mixture by scraping its surface.

[0101] It is thus observed that, on the one hand, the crosslinking reaction of the alginate occurs instantaneously upon contact with the ions of an alkaline earth metal present in the second mixture; on the other hand, this reaction is localized at the level of the surface of the gel.

[0102] The surface of the gel then hardens sufficiently to allow fingers to glide over the gel layer without destroying it, which facilitates the application and spreading in a thin layer of the second mixture over the entire surface of the gel of the first mixture.

[0103] According to one embodiment, following the application of the second mixture, the individual allows it to rest for between 1 and 30 minutes, preferably between 5 and 15 minutes, even more preferably 10 minutes.

[0104] Under the effect of the acidifying agent contained in the second mixture, the pH of the gel layer decreases, which causes the dissociation of the alkaline earth metal salt present in the gel and the release of corresponding ions throughout the entire mass of the gel. This then leads to the endogenous and deep cross-linking of the entire alginate mass of the first mixture.

[0105] This process thus leads to the complete plasticization of the first layer of gel (corresponding to the first mixture), to form a coherent, homogeneous and continuous plastic film, with sufficient mechanical characteristics to allow the film to be peeled off in one piece by peel-off effect.

[0106] Indeed, in the first mixture, the alkaline earth metal salt is homogeneously incorporated into the alginate, resulting in a very efficient crosslinking reaction. This leads to the formation of a plastic film with good mechanical properties, thus facilitating tearing and the desired peel-off effect.

[0107] Thus, according to one embodiment, in the case of the second mixture comprising a gelling agent, the successive implementation steps may be as follows: • Spreading the first mixture in a thick layer on the skin; • Spreading the second mixture over the first mixture: The rapid cross-linking of the alginate contained in the first mixture under the effect of the Ca2+ ions of the second mixture is localized at the contact surface of the two gels. This allows the second mixture to be spread and smoothed into a thin layer, without destroying the layer of the first gel; • Deep crosslinking reaction of the first mixture: Due to the decrease in pH in the first mixture (caused by the acidifying agent present in the second mixture), the calcium carbonate in the first mixture dissolves and releases Ca2+ ions. Deep crosslinking of the alginate then occurs gradually throughout the entire layer of the first mixture. • Complete plasticization and homogeneous film formation: At the end of the reaction, the entire layer of the first mixture is plasticized and can be removed by peeling or "peel-off" effect.

[0108] According to another embodiment, in the case of the second mixture without gelling agent, the successive implementation steps may be as follows: • Spreading the first mixture in a thick layer on the skin; • Spraying the second mixture onto the first mixture: Crosslinking rapid surface reaction of the alginate contained in the first mixture under the effect of the Ca2+ ions from the second mixture; • Deep crosslinking reaction of the first mixture: Due to the decrease in pH in the first mixture (caused by the acidifying agent present in the second mixture), the calcium carbonate in the first mixture dissolves and releases Ca2+ ions. Deep crosslinking of the alginate then occurs gradually throughout the entire layer of the first mixture. • Complete plasticization and homogeneous film formation: At the end of the reaction, the entire layer of the first mixture is plasticized and can be removed by peeling or "peel-off" effect.

[0109] According to one embodiment, the non-therapeutic cosmetic skin care process for an individual includes, before the step of applying the first mixture to the skin of the face of said individual, a step of applying a cosmetic composition intended to prepare the skin.

[0110] The effectiveness of topical preparations is improved by adequate skin preparation.

[0111] Preferably, said cosmetic composition intended to prepare the skin is a composition which gives the skin improved permeability to the active cosmetic ingredients of aqueous non-therapeutic cosmetics for the preparation of a peelable mask.

[0112] Even more preferably, this cosmetic composition intended to prepare the skin may include ingredients selected from: surfactants, keratolytic agents, or humectant agents.

[0113] According to one embodiment, the non-therapeutic cosmetic skin care process for an individual includes, before the step of applying the first mixture to the facial skin of said individual, a step of applying a cosmetic composition comprising cosmetic active ingredients.

[0114] Such cosmetic active ingredients are the same active compounds known to those skilled in the art and which can also be included in the composition according to the invention.

[0115] In the case where a preparation step is present, this step of applying a cosmetic composition comprising cosmetic active ingredients is carried out between the skin preparation step and the step of applying the first mixture according to the invention.

[0116] This cosmetic composition comprising cosmetic active ingredients is preferably in the form of a lotion, serum or aqueous gel.

[0117] The cosmetic care process according to the invention can be repeated as many times as necessary by the individual.

[0118] Indeed, for certain cosmetic applications, it is advantageous to combine the periodic application, for example twice weekly, of the composition according to the invention with, on the one hand, the daily application of a topical application preparation of the "day care" type, in which the same cosmetic active ingredients or those present in the composition according to the invention are incorporated, and / or on the other hand the application of a topical application preparation of the "night care" type, in which these same cosmetic or pharmacological active ingredients are present.

[0119] According to a third aspect, the invention relates to a kit for preparing a peelable mask comprising an aqueous composition for preparing a non-therapeutic peelable cosmetic mask according to the invention, comprising the first mixture and the second mixture.

[0120] The mixtures according to the present invention can indeed be offered in a preparation kit consisting of two containers, the contents of which can be applied successively to the skin. These containers can be chosen from tubes, bottles, or jars. The containers preferably have a volume between 15 and 300 mL.

[0121] The invention also allows the two mixtures according to the invention to be packaged in single-dose containers. These containers may advantageously be chosen, without limitation, from among the single-dose containers commonly used in cosmetics, such as sachets, cartons, disposable capsules, or twist-off tubes. The single-dose containers preferably have a volume between 5 and 30 mL.

[0122] According to a fourth aspect, the invention relates to a method for preparing the aqueous composition according to the invention comprising: • To prepare the first mixture, the successive steps are: i. Solubilization in water of said alkali metal alginate at room temperature, under medium stirring; ii. Once the alginate is completely dissolved, add said alkalizing compound to adjust the pH above 6; iii. Once the pH has stabilized, said salt of an insoluble alkaline earth metal at basic or neutral pH is added to the mixture, at room temperature and under medium stirring; • To prepare the second mixture, the successive steps are: i. Heating a volume of water to 70°; ii. Addition of said soluble salt of an alkaline earth metal into said volume of water; iii. After complete dissolution of said soluble salt of an alkali-earth metal in water, the mixture is allowed to cool under moderate stirring at room temperature. iv. Addition to said mixture of said acidifying compound; v. Allowing the said mixture to rest until the pH stabilizes between 2 and 4, preferably between 3.2 and 3.6, and until a homogeneous mixture is obtained; vi. Once the pH has stabilized and the mixture is homogeneous, the solution is then ready to be packaged in a spray bottle.

[0123] Preferably, the average agitation speed is between 500 and 2000 rpm, of Preferred speed: 800 rpm.

[0124] According to one embodiment, between step i. and step ii. of the first mixing, once the alginate is completely dissolved, and still at room temperature and under medium stirring, the mixture of water-soluble polymers intended to strengthen the mechanical properties of the plastic film obtained by crosslinking the film-forming polymer is added.

[0125] According to one embodiment, between steps i. and ii. of the first mixing, after the addition of said water-soluble polymers, it is advantageous to incorporate into the mixture the active ingredients and fillers possibly provided for in the formula and to mix the whole under medium stirring until a homogeneous gel is obtained.

[0126] After the addition of the calcium source, which is dispersed in the mixture, the pH will advantageously be from 8 to 9.

[0127] In the gelling embodiment, said gelling agent is incorporated into water heated to 70°C under medium stirring, before step i. of preparing the second mixture.

[0128] According to a fifth aspect, the invention relates to the use of the kit according to the invention to prepare extemporaneously a peelable skin mask.

[0129] Preferably said mask is non-therapeutic cosmetic.

[0130] According to a sixth aspect, the invention relates to the use of an aqueous composition comprising: • A first mixture comprising: i. An alginate gel of at least one alkali metal; ii. At least one salt of an alkaline earth metal that is insoluble at basic or neutral pH; iii. At least one alkalizing compound; • A second mixture comprising: i. At least one soluble salt of an alkaline earth metal; ii. At least one acidifying compound; for the preparation of a non-therapeutic peelable cosmetic mask.

[0131] According to a seventh aspect, the invention relates to an aqueous composition for use in the preparation of a peelable mask comprising dermatological active ingredients, comprising: • A first mixture comprising: i. An alginate gel of at least one alkali metal; ii. At least one salt of an alkaline earth metal that is insoluble at basic or neutral pH; iii. At least one alkalizing compound; • A second mixture comprising: i. At least one soluble salt of an alkaline earth metal; ii. At least one acidifying compound.

[0132] According to an eighth aspect, the invention relates to a dermatological treatment method comprising: • Application of the first mixture to the facial skin of the said individual; • Application of the first mixture to the facial skin of the said individual, followed by the application of the second mixture.

[0133] One or more mixtures according to this aspect may include therapeutic actives for treating a skin condition by transcutaneous administration.

[0134] According to one embodiment, said therapeutic agents make it possible to treat acne, psoriasis and / or eczema. Figures

[0135] [Fig-1] is a diagram representing the spreading of the first mixture in a thick layer on the skin.

[0136] [Fig.2] is a diagram representing the spreading of the second gelled mixture on the first mixture.

[0137] [Fig.3] is a diagram representing the deep crosslinking reaction of the first mixture.

[0138] [Fig.4] is a diagram representing the complete lamination and the formation of the homogeneous film.

[0139] [Fig.5] is a diagram representing the spraying of the second ungelled mixture onto the first mixture. Definitions

[0140] Alginates are extracted from the cell wall fluids of brown algae. They are polymers composed of two monomers: mannuronate, or mannuronic acid, which may be more or less acetylated, and guluronate, or guluronic acid. Alginates have the ability to form viscous colloidal solutions, or gels, with water. Their rheological properties allow them to be spread in a thin layer on the skin, either with the fingers or with a suitable tool (brush or spatula). They can also form solid, homogeneous plastic films through the cross-linking reaction of the alginate gel with an alkaline earth metal in solution in its ionic state. This cross-linking mechanism follows kinetics that depend, among other things, on the availability of alkaline earth ions within the alginate gel.

[0141] By "aqueous composition" is understood that the composition in its form prior to use by an individual is a homogeneous mixture consisting mainly of water and other dissolved chemical species.

[0142] The term "peel-off mask" or "peelable mask" means a mask applied to the A face or other area of ​​skin that dries on the skin after application and is then peeled off by the user. When this type of mask is removed, blackheads, dead skin cells, dirt, and sebum deposits adhere to it. These masks are occlusive.

[0143] The alkali metals are lithium, sodium, potassium, rubidium, cesium, and francium. In the context of the invention, sodium and potassium are preferably used.

[0144] The alkaline earth metals are beryllium, magnesium, calcium, strontium, barium, and radium. The alkaline earth metals insoluble at basic or neutral pH are the salts of these metals that are soluble in water at pH greater than or equal to 7.

[0145] The term "basifying compound" or "base" refers to a chemical capable of capturing one or more protons or, conversely, of donating electrons. These products have a pH greater than 7 and possess alkaline properties that raise the pH of the mixture.

[0146] The term "acidifying compound" or "acid" refers to a chemical compound capable of donating protons or, conversely, capturing electrons. These products have a pH below 7 and possess acidifying properties that lower the pH of the mixture.

[0147] The terms "first mixture" and "second mixture" refer to separate compositions comprising the indicated compounds. These mixtures are then brought into contact at the time of application to the individual's skin.

[0148] By "ambient temperature" is meant a temperature corresponding to about 25°C at about a pressure of 100 kPa.

[0149] By "hydrophilic polymer having the property of forming an aqueous gel with suitable pseudo-plastic properties" is meant a water-soluble polymer forming a gel whose rheological properties allow it to be spread in a thin layer on the skin, with the fingers or with the aid of a suitable utensil (brush or spatula).

[0150] By topical application preparation of the type “day care” and “night care” means any form of topical application preparation, presented in the form of an aqueous or hydroalcoholic solution, a water-in-oil or oil-in-water emulsion, a microemulsion, an aqueous or anhydrous gel, a serum, or even a vesicle dispersion, a patch, a cream, a spray, an ointment, a cream, a lotion, a colloid, a solution, a suspension or other, and offered for application to the skin, respectively in the morning upon waking, and in the evening before bedtime.

[0151] For the purposes of this invention, "non-therapeutic" means a cosmetic application not intended to treat a patient. In fact, the cosmetic use according to this invention does not act as a medicinal product for the treatment of diseases.

[0152] For the purposes of this invention, "topical application" means application to the skin (including the scalp) and mucous membranes.

[0153] For the purposes of this invention, "cosmetically acceptable" means something that is useful in the preparation of a cosmetic composition, that is generally safe, non-toxic and neither biologically nor otherwise undesirable, and that is acceptable for cosmetic use, in particular by topical application to the skin.

[0154] By "cosmetically effective quantity" is meant a quantity that enables the effects claimed according to the invention to be obtained.

[0155] In the description and the following examples, unless otherwise stated, percentages are percentages by weight, and value ranges expressed as "between ... and ..." include the specified lower and upper bounds. The following examples are given by way of illustration and are not intended to limit the scope of the invention.

[0156] By "or a mixture of these" is understood that each of the listed compounds can be mixed with one or more of the other listed compounds. Examples

[0157] Example 1: Test for obtaining a peelable mask (gelled mixture 2)

[0158] In order to test the effectiveness of peeling the mask obtained using the composition according to the invention, 10 users are recruited to use the compositions according to the invention to form peelable masks on their faces.

[0159] To do this, they use the following mixtures:

[0160] First mixture (weight percentages of the first mixture): • Demineralized water: q.s. 100% • Sodium alginate: 3% • Carrageenan: 0.4% • Pullulane: 0.5% • Gum arabic: 0.5% • Erythritol: 1% • Rice starch: 3% • Clay: 0.5% • Kaolin: 0.5% • Calcium carbonate: 0.5% • Conservative

[0161] Second mixture (weight percentages of the second mixture): • Demineralized water: q.s. 100% • Calcium lactate: 5% • Carrageenan: 0.5% • SynerGX® (Guar Gum and Xanthan Gum): 1% • Gluconodeltalactone: 5% • Phytic acid: 1% • Conservative

[0162] The user thus performs the successive implementation steps in order to obtain the peelable mask: • Spreading the first mixture in a thick layer on the skin ([Fig. 1]); • Spreading the second mixture over the first mixture ([Fig.2]).

[0163] Thus, under the effect of the decrease in pH in the first mixture (due to the acidifying agent present in the second mixture), the calcium carbonate present in the first mixture dissolves and releases Ca2+ ions. Deep cross-linking of the alginate then occurs gradually throughout the entire layer of the first mixture ([Fig.3]).

[0164] At the end of the reaction, the entire layer of the first mixture is plasticized and can be removed by peeling or "peel-off" effect ([Fig.4]).

[0165] After about 10 minutes of application to their faces, users seek to remove the peelable mask.

[0166] All users reported that they had no difficulty removing the mask by hand, with the surface fragments peeling off minimally, either in large sections or all at once, from the user's skin. No pain was reported by these users. Users did not require any external assistance to remove the mask.

[0167] Example 2: Test for obtaining a peelable mask (mixture 2 without gelling agent)

[0168] In order to test the effectiveness of peeling the mask obtained using the composition according to the invention, 10 users are recruited to use the compositions according to the invention to form peelable masks on their faces.

[0169] To do this, they use the following mixtures:

[0170] First mixture (weight percentages of the first mixture): • Demineralized water: q.s. 100% • Sodium alginate: 3% • Carrageenan: 0.4% • Pullulane: 0.5% • Gum arabic: 0.5% • Erythritol: 1% • Rice starch: 3% • Clay: 0.5% • Kaolin: 0.5% • Calcium carbonate: 0.5% • Conservative

[0171]

[0172]

[0173]

[0174]

[0175]

[0176] Second mixture (weight percentages of the second mixture): • Demineralized water: q.s. 100% • Calcium lactate: 5% • Gluconodeltalactone: 5% • Phytic acid: 1% • Conservative The user thus carries out the successive implementation steps in order to obtain the peelable mask: • Spreading the first mixture in a thick layer on the skin ([Fig. 1]); • Spraying the second mixture onto the first mixture ([Fig.5]) Thus, due to the decrease in pH in the first mixture (caused by the acidifying agent present in the second mixture), the calcium carbonate in the first mixture dissolves and releases Ca2+ ions. Deep cross-linking of the alginate then occurs gradually throughout the entire layer of the first mixture ([Fig.3]). At the end of the reaction, the entire layer of the first mixture is plasticized and can be removed by peeling or "peel-off" effect ([Fig.4]). After about 10 minutes of wearing it on their faces, users try to remove the peelable mask. All users reported having no difficulty removing the mask by hand, with the surface material peeling off minimally, either in large sections or all at once, from the user's skin. No pain was reported by these users. Furthermore, the users did not require any outside assistance to remove their mask.

Claims

Demands

1. Aqueous composition for the preparation of a peelable non-therapeutic cosmetic mask comprising: • A first mixture comprising: i. An alginate gel of at least one alkali metal; ii. At least one salt of an insoluble alkaline earth metal at basic or neutral pH; iii. At least one alkalizing compound; • A second mixture comprising: i. At least one soluble salt of an alkaline earth metal; ii. At least one acidifying compound.

2. Aqueous composition for the preparation of a peelable non-therapeutic cosmetic mask according to the preceding claim, wherein said alkali metal alginate is selected from sodium alginate, potassium alginate, or a mixture thereof, preferably sodium alginate.

3. Aqueous composition for the preparation of a peelable non-therapeutic cosmetic mask according to any one of the preceding claims, wherein said salt of an insoluble alkaline earth metal at basic or neutral pH is selected from calcium sulfate, calcium carbonate, or a mixture thereof, preferably calcium carbonate.

4. Aqueous composition for the preparation of a peelable non-therapeutic cosmetic mask according to any one of the preceding claims, wherein said alkalizing compound is selected from sodium hydroxide, potassium citrate, triethanolamine, or a mixture thereof.

5. Aqueous composition for the preparation of a peelable non-therapeutic cosmetic mask according to any one of the preceding claims, wherein said soluble salt of an alkaline earth metal is selected from calcium chloride, calcium lactate, calcium gluconate or a mixture thereof.

6. An aqueous composition for the preparation of a peelable, non-therapeutic cosmetic mask according to any one of the preceding claims, comprising: • A first mixture comprising: i. Between 0.5% and 10% by weight of the first mixture of a • A second mixture comprising: i. Between 0.1% and 5% by weight of the first mixture of at least one salt of an insoluble alkaline earth metal at basic or neutral pH; iii. Between 0.1% and 5% by weight of the first mixture of at least one alkaline compound; • A second mixture comprising: i. Between 0.5% and 10% by weight of the second mixture of at least one soluble salt of an alkaline earth metal; ii. Between 0.1% and 10% by weight of the second mixture of at least one acidifying compound.

7. Aqueous composition for the preparation of a peelable non-therapeutic cosmetic mask according to any one of the preceding claims, wherein said second mixture comprises a gelling agent.

8. A non-therapeutic cosmetic skincare method for an individual, comprising the application of an aqueous composition according to any one of the preceding claims in order to obtain a peelable mask, comprising the successive steps of: • Application to the facial skin of said individual of the first mixture; • Application to the first mixture applied to the facial skin of said individual of the second mixture.

9. Kit for preparing a peelable mask comprising an aqueous composition for preparing a non-therapeutic peelable cosmetic mask according to any one of claims 1 to 7, comprising the first mixture and the second mixture.

10. A process for preparing the aqueous composition according to any one of claims 1 to 7 comprising: • In order to prepare the first mixture, the successive steps of: i. Solubilization in water of said alkali metal alginate at room temperature, under medium stirring; ii. Once the alginate is completely dissolved, add said alkalizing compound to adjust the pH above 6; iii. Once the pH has stabilized, said salt of an alkali-noterrous metal insoluble at basic or neutral pH is added to the mixture, at room temperature and under medium stirring; To prepare the second mixture, the following successive steps are required: i. Heating a volume of water to 70°; ii. Addition of said soluble salt of an alkaline earth metal into said volume of water; iii. After complete dissolution of said soluble salt of an alkaline earth metal in water, the mixture is left to cool under moderate stirring at room temperature. iv. Addition to said mixture of said acidifying compound; v. Allowing the said mixture to rest until the pH stabilizes between 2 and 4, preferably between 3.2 and 3.6, and until a homogeneous mixture is obtained; vi. Once the pH has stabilized and the mixture is homogeneous, the solution is then ready to be packaged in a spray bottle.

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