Novel solid cosmetic composition for hygiene and care of skin and hair

Abstract

The present invention relates to a solid cosmetic composition comprising: a mixture of surfactants, the mixture comprises at least one anionic surfactant selected from the group consisting of acylglutamic acids and salts thereof, at least one nonionic surfactant selected from the group consisting of alkyl glycosides wherein the alkyl group comprises 8 to 16 carbon atoms, and at least one anionic surfactant selected from the group consisting of acyllactylic acids and salts thereof; and at least one cosmetically acceptable carrier. The composition is free of the following: a surfactant containing an isethionic acid or isethionate group and a surfactant containing a sulfosuccinic acid or sulfosuccinate group. It is particularly suitable for hygiene and care of skin and hair.

Description

Technical Field

[0001] The present invention relates to a cosmetic composition in solid form and to the use of such a composition for washing and / or caring for the skin and / or hair. The present invention also relates to a cosmetic treatment method for the hygiene and / or care of the skin and / or hair using such a composition. Background Art

[0002] Currently, the solid cosmetics market is booming, and many companies are bringing to the market compositions in solid form for washing and / or caring for the face, body or hair, which are more environmentally friendly than liquid compositions.

[0003] The oldest solid cosmetic composition widely used by consumers is soap, which is produced by a saponification reaction. However, due to their high pH (usually greater than 10), soaps are very irritating on the skin, especially sensitive skin, and are not suitable for use on the hair.

[0004] Recently, synthetic detergents, synthetic surfactants, have become an advantageous alternative to products produced by saponification. In fact, synthetic detergents have the cleaning properties of conventional soaps, while being less irritating to the skin. The synthetic detergents contained as foaming agents in solid cosmetic compositions currently available on the market are mainly of the type containing isethionate groups, such as sodium cocoyl isethionate (INCI name) or sulfosuccinate groups, such as disodium lauryl sulfosuccinate (INCI name). However, such substances with good foaming properties are not natural and / or certified by COSMOS, which is the following standard that defines the criteria that must be followed in order to provide consumers with the guarantee that their products are truly organic or natural cosmetics manufactured according to the highest possible sustainability standards. However, consumers are increasingly concerned about the composition of their cosmetic products. Therefore, they look for products that do not contain chemicals, preferably natural ingredients that are known for their excellent tolerance and affinity with the skin and are more environmentally friendly.

[0005] Extract from Mintel database, accession number 8729463, "Volume & Anti-Frizz 100% Natural Custom Solid Shampoo", 2021 describes a shampoo in solid form which is free of surfactants containing isethionic acid or isethionic acid groups and surfactants containing sulfosuccinic acid or sulfosuccinic acid groups and contains as surfactants substances with the INCI names sodium cocoyl glutamate, sodium lauroyl lactylate, and a mixture of arachidyl glucoside with arachidyl alcohol and behenyl alcohol. However, such shampoos are very hard and sticky, making them difficult to use.

[0006] The present invention aims to overcome the disadvantages of solid cosmetic compositions proposed in the prior art, in particular those outlined above, by proposing a solid cosmetic composition having a physiological pH, which is mild on the skin, contains a maximum of natural ingredients and which is particularly free of any surfactants of the isethionate or sulfosuccinate type, while having foaming properties at least as good, if not better, than those of prior art compositions using these non-natural synthetic detergents.

[0007] Further objects of the present invention include making such compositions contain as few ingredients as possible and making them suitable for use on all skin types, including sensitive skin and atopic skin.

[0008] The present invention also contemplates such a solid composition having sufficient consistency and not being too hard so that it does not break down over time when handled or stored, yet not being so soft and sticky that its use would be impractical and unpleasant. Summary of the invention

[0009] The inventors of the present invention have found that these objects are achieved by using a specific combination of natural synthetic detergents which unexpectedly have particularly good foaming properties on contact with water and which enable the formation of solid compositions which are neither very sticky nor very hard.

[0010] According to a first aspect, the present invention provides a solid cosmetic composition which is particularly suitable for topical use, in particular on the skin and hair. The composition comprises: - a mixture of surfactants comprising at least one anionic surfactant chosen from acyl glutamic acids and cosmetically acceptable salts thereof, at least one nonionic surfactant chosen from alkyl glucosides wherein the alkyl group contains from 8 to 16 carbon atoms, and at least one anionic surfactant chosen from acyl lactyl lactic acids and cosmetically acceptable salts thereof, - and at least one cosmetically acceptable excipient.

[0011] Furthermore, the composition comprises less than 5% by weight of water relative to the total weight of the composition and is free of surfactants containing isethionic acid or isethionate groups and surfactants containing sulfosuccinic acid or sulfosuccinate groups.

[0012] Solid compositions are defined in this specification in a conventional manner as compositions in the form of blocks that do not flow under the effect of their weight. This definition specifically excludes powder forms. More specifically, according to the present invention, solid compositions are understood to be any compositions having a hardness (compressive strength) greater than or equal to 20 grams at ambient temperature, i.e. at a temperature included between 20° C. and 25° C. This hardness can be measured by penetrating the matrix of the composition to a thickness of 8 mm with a cylindrical probe having a diameter of 0.8 cm and at a speed of 1 mm / s, and measuring the penetration of the probe. Any texture analysis device can be used for this purpose, in particular the TA.XT+ analyzer sold by Stable Micro Systems.

[0013] The solid cosmetic composition according to the present invention is intended to be used directly in its solid form, particularly for the type of skin and / or hair hygiene and / or care, which is contrary to the solid composition intended to be dissolved in water and then used to constitute a liquid composition (which is the final form they are intended to use). Therefore, the composition according to the present invention preferably does not contain any material that can produce agitation when in contact with water, such as an effervescent base, particularly a combination of an organic acid and an alkali metal and / or alkaline earth metal bicarbonate, such as a combination of citric acid and sodium carbonate. It also preferably does not contain any of the following listed gums, which are conventionally used to stabilize the aqueous phase in the liquid composition, and in view of a very small amount of water or even the absence of water in the composition, its presence is harmful to the consistency of the composition: xanthan gum, diutan gum, gellan gum, sclerotium gum, succinoglucan gum, gum arabic, locust bean gum, Tamarindus indica seed gum, Caesalpinia spinosa gum. The solid cosmetic composition according to the present invention can be optionally packaged in a refillable packaging device, for example, in the form of a rectangular rod, a round rod, a ball or a strip.

[0014] In this specification, "cosmetically acceptable" is understood to mean that the salt or excipient is suitable for contact with human and animal cells, especially skin or hair cells. The excipient preferably has a pleasant smell, color and feel, and does not produce unacceptable discomfort that may prevent the user from using the composition according to the invention.

[0015] In this specification, "at least one" is understood to mean a single compound or a mixture of several such compounds. Thus, the mixture of surfactants of the composition according to the invention contains: - a single anionic surfactant selected from acylglutamic acids and cosmetically acceptable salts thereof, or a plurality of such anionic surfactants, - a single nonionic surfactant selected from alkyl glucosides wherein the alkyl group contains from 8 to 16 carbon atoms, or a plurality of such nonionic surfactants, - a single anionic surfactant selected from acyl lactylactic acid and cosmetically acceptable salts thereof, or a plurality of such anionic surfactants.

[0016] Such specific mixtures of surfactants, all of which are natural, advantageously ensure good foaming properties of the composition when it comes into contact with water, and good quality of the foam formed. Without assuming knowledge of the phenomena underlying this performance of the mixtures of surfactants according to the invention, it can be considered that they are due to the synergistic effect of the specific groups carried by these surfactants, in particular the glutamic acid / glutamate, glucoside and lactyllactic acid / lactoylactate groups, and the chain length of the alkyl group of the nonionic surfactant, which contributes to its foaming properties. This performance is advantageously achieved in the absence of synthetic detergents in the composition, which are conventionally used in solid cosmetic compositions for skin and hair hygiene or care, which have the disadvantage of being of non-natural origin.

[0017] Thus, the composition according to the invention does not contain any surfactant containing an isethionate or isethionate group, in particular any surfactant chosen from acyl isethionates or their salts, such as the substance with the INCI name Sodium Cocoyl Isethionate. It also does not contain any surfactant containing a sulfosuccinate or sulfosuccinate group, in particular any surfactant chosen from alkyl sulfosuccinates or their salts, such as the substance with the INCI name Disodium Lauryl Sulfosuccinate.

[0018] Furthermore, the solid composition according to the invention advantageously does not contain soap, i.e. substances obtained by saponification, such as those with the INCI names Sodium Palmitoleate, Sodium Cocoate, Sodium Olivetate, Sodium Stearate, etc. The pH of the composition according to the invention is therefore advantageously close to the physiological pH of the skin. It is preferably comprised between 4.5 and 7, more preferably between 4.5 and 6 and particularly preferably between 5 and 6. The pH of the solid composition according to the invention can be measured by dissolving the composition in water, for example at a ratio of 1 g of composition in 100 g of water, and measuring the pH of the solution obtained.

[0019] The composition according to the invention comprises less than 5% by weight of water relative to the total weight of the composition. The water content of the composition according to the invention is preferably less than or equal to 4% by weight, preferably less than or equal to 3% by weight, in particular less than or equal to 2% by weight, for example less than or equal to 1% by weight, relative to the total weight of the composition. In a particular embodiment of the invention, the composition contains no water or only traces of water. In an alternative embodiment of the invention, the composition comprises from 0.5% to 4% by weight of water, in particular from 1% to 3% by weight of water, relative to the total weight of the composition.

[0020] Furthermore, the composition according to the invention may comply with one or more of the features described hereinafter, used alone or in each of their technically feasible combinations.

[0021] The ingredients contained in the composition according to the invention are preferably natural, thus satisfying the very strong demand for formulations containing natural ingredients, which has been a feature of the cosmetics market for many years. According to the calculation method set forth in standard ISO16128:2017, the composition according to the invention preferably contains at least 80%, preferably at least 90%, and preferably at least 95% of natural ingredients.

[0022] Besides the above mentioned non-natural ingredients, such as surfactants containing isethionic acid or isethionic acid groups, and surfactants containing sulfosuccinic acid or sulfosuccinate groups, and the non-natural ingredients mentioned below, the compositions according to the invention are preferably free of paraffins.

[0023] Furthermore, the composition according to the invention preferably does not contain any ingredients which irritate the skin, cause drying, or which may produce an adverse or allergic reaction. Thus, the composition according to the invention preferably does not contain any anionic surfactants which contain at least one sulfate group, i.e. an -O-SO3H or -O-SO2-O- group, such as laureth sulfate or lauryl sulfate. Although sulfated surfactants have particularly good foaming properties, they do tend to be irritating on the skin.

[0024] Furthermore, also in order to improve its tolerability by the user, the composition according to the invention is preferably free of any compounds having acrylate functions and silicones.

[0025] In a preferred embodiment of the invention, the content of the mixture of surfactants is comprised between 15% and 50% by weight, preferably between 20% and 40% by weight, in particular between 20% and 35% by weight, relative to the total weight of the composition. These value ranges ensure that the composition has good foaming properties and that the foam formed is of good quality, while being associated with low manufacturing costs for the composition.

[0026] The total content of nonionic surfactants chosen from alkyl glucosides wherein the alkyl group comprises from 8 to 16 carbon atoms is preferably comprised between 1 and 5% by weight, in particular between 1 and 3% by weight, relative to the total weight of the composition.

[0027] The total content of anionic surfactants chosen from acylglutamic acids and cosmetically acceptable salts thereof is preferably comprised between 10 and 35% by weight relative to the total weight of the composition.

[0028] The total content of anionic surfactants chosen from acyl lactylactic acid and cosmetically acceptable salts thereof is preferably comprised between 2 and 10% by weight relative to the total weight of the composition.

[0029] In a particular embodiment of the invention, the total content of anionic surfactants chosen from acylglutamic acids and cosmetically acceptable salts thereof is comprised between 50 and 80% by weight, in particular between 60 and 70% by weight, relative to the total weight of the mixture of said surfactants.

[0030] The mass ratio of the nonionic surfactant chosen from alkyl glucosides wherein the alkyl group contains from 8 to 16 carbon atoms to the anionic surfactant chosen from acyl lactylactic acids and cosmetically acceptable salts thereof is preferably comprised between 0.3 and 1 and more preferably between 0.4 and 0.8, in particular comprised between 0.5 and 0.6.

[0031] The anionic surfactant selected from acylglutamic acid and its cosmetically acceptable salt is preferably selected from acylglutamic acid, whose acyl group comprises a straight or branched, saturated or unsaturated hydrocarbon chain with 8 to 30 carbon atoms, preferably 10 to 20 carbon atoms and more preferably 12 to 18 carbon atoms. Acyl group can be selected from lauroyl, myristoyl, palmitoyl, stearyl, olive oil acyl, coconut oil acyl and oleoyl in particular. The cosmetically acceptable salt of acylglutamic acid can be selected from alkali metal salts, alkaline earth metal salts and ammonium salts. For example, it is selected from sodium salt, potassium salt, lithium salt or magnesium salt, sodium salt and potassium salt being particularly preferred within the scope of the present invention. The anionic surfactant chosen from acylglutamic acids and cosmetically acceptable salts thereof may for example be chosen from the group consisting of compounds with the INCI names Sodium Cocoyl Glutamate, Disodium Cocoyl Glutamate, Sodium Myristoyl Glutamate, Sodium Lauroyl Glutamate, Potassium Lauroyl Glutamate, Potassium Cocoyl Glutamate and Sodium Stearoyl Glutamate. Several anionic surfactants chosen from acylglutamics and cosmetically acceptable salts thereof may be used in the composition according to the invention, which composition may for example contain any mixture of two or more of the compounds listed above. The composition according to the invention preferably comprises a single anionic surfactant chosen from acylglutamics and cosmetically acceptable salts thereof.

[0032] The nonionic surfactant chosen from the group consisting of alkyl glucosides in which the alkyl group contains from 8 to 16 carbon atoms is preferably chosen from the compounds with the INCI names octyl glucoside, lauryl glucoside and decyl glucoside. Several nonionic surfactants chosen from the group consisting of alkyl glucosides in which the alkyl group contains from 8 to 16 carbon atoms can be used in the composition according to the invention, which composition can, for example, contain any mixture of two or more of the aforementioned compounds (octyl glucoside, lauryl glucoside and decyl glucoside). The composition according to the invention preferably comprises a single nonionic surfactant chosen from the group consisting of alkyl glucosides in which the alkyl group contains from 8 to 16 carbon atoms.

[0033] The anionic surfactant selected from acyl lactylic acid and its cosmetically acceptable salts is preferably selected from acyl lactylic acid, the acyl group of which comprises a linear or branched, saturated or unsaturated hydrocarbon chain having 8 to 30 carbon atoms, preferably 10 to 20 carbon atoms and more preferably 12 to 18 carbon atoms. The acyl group can be selected in particular from caproyl, lauroyl, myristoyl, palmitoyl, stearoyl, isostearoyl, oliveoyl, cocoyl and oleoyl. The cosmetically acceptable salt of acyl lactylic acid can be selected from alkali metal salts, alkaline earth metal salts and ammonium salts. For example, it is selected from sodium, potassium, lithium or magnesium salts, sodium and potassium salts being particularly preferred within the scope of the present invention. The anionic surfactant selected from acyl lactylic acid and its cosmetically acceptable salts is, for example, selected from compounds having the INCI names sodium lauroyl lactylate, sodium stearoyl lactylate, sodium caproyl lactylate and sodium isostearoyl lactylate. In a preferred embodiment of the invention, the anionic surfactant selected from acyl lactyl lactylic acids and cosmetically acceptable salts thereof necessarily comprises sodium lauroyl lactylate. Several anionic surfactants selected from acyl lactyl lactylic acids and cosmetically acceptable salts thereof may be used in the composition according to the invention, which composition may for example contain a mixture of sodium lauroyl lactylic acid and sodium stearoyl lactylic acid. The composition according to the invention preferably comprises a single anionic surfactant selected from acyl lactyl lactylic acids and cosmetically acceptable salts thereof, and preferably it is a lauroyl lactylate, for example sodium lauroyl lactylate.

[0034] In general, the composition according to the invention preferably contains as few surfactants as possible. Thus, in a specific embodiment of the invention, the composition comprises no more than 6 surfactants, preferably no more than 5 surfactants, more preferably no more than 4 surfactants and preferably 3 surfactants. As mentioned above, good foaming properties can be achieved with any combination of a single compound from each of the three surfactant families defined above, advantageously minimizing the number of ingredients present in the composition.

[0035] The composition according to the invention may contain other anionic surfactants than those defined above. It preferably does not contain anionic surfactants than acyl glutamates and acyl lactylates. Similarly, the composition according to the invention may contain other nonionic surfactants than those defined above. It preferably does not contain nonionic surfactants than alkyl glycosides whose alkyl groups have from 8 to 16 carbon atoms. In particular, it preferably does not contain any alkyl glucoside whose alkyl groups have more than 16 carbon atoms. The presence of such alkyl glucosides in the composition is particularly detrimental to the hardness and viscosity of the composition.

[0036] The composition according to the invention may also comprise one or more cationic surfactants, for example when it is intended for cosmetic treatment of hair, for conditioning treatment. It is preferably free of non-natural cationic surfactants and, more generally, preferably free of cationic surfactants.

[0037] The composition according to the invention may also comprise one or more amphoteric surfactants. It is preferably free of non-natural amphoteric surfactants, such as betaine surfactants, and more generally, preferably free of amphoteric surfactants.

[0038] In a particular embodiment of the invention, the mixture of surfactants of the composition consists of: - one or more, preferably only one, anionic surfactant selected from acylglutamic acids and cosmetically acceptable salts thereof, - one or more, preferably a single, nonionic surfactant selected from alkyl glucosides wherein the alkyl group contains from 8 to 16 carbon atoms, - and one or more, preferably only one, anionic surfactant selected from acyl lactylic acid and cosmetically acceptable salts thereof.

[0039] The composition according to the invention may also contain one or more emulsifiers, such as glycol palmitate (INCI name). Alternatively, it may not contain any. It preferably does not contain emulsifiers formed by mixtures with the INCI name "arachidyl alcohol, arachidyl alcohol / behenyl alcohol, arachidyl glucoside", such as those with the name 202 Mixture sold.

[0040] More generally, the composition according to the invention preferably does not contain mixtures of arachidyl alcohol and arachidyl glucoside. Indeed, such mixtures impart a high degree of hardness and stickiness to the composition, making it less easy to use.

[0041] In a particular embodiment of the present invention, the at least one cosmetically acceptable excipient is selected from the group consisting of thickeners, fillers, emollients, conditioners, stabilizers, fragrances, dyes, pigments and mixtures thereof.

[0042] The composition according to the invention particularly preferably comprises at least one fatty phase thickener. The total content of thickener in the composition is preferably comprised between 25% and 65% by weight, preferably between 30% and 60% by weight, in particular between 35% and 55% by weight, relative to the total weight of the composition. This concentration of thickener in the composition, combined with the filler which may also be included therein as explained below, advantageously ensures that the composition has optimal hardness and viscosity properties, in particular a hardness low enough so that the composition does not crumble when it is handled by the user, and a viscosity high enough so that the composition has good cohesion, which does not impair its practical and pleasant properties.

[0043] The composition according to the invention may in particular contain one or more thickeners chosen from fatty alcohols (preferably C16-C22), fatty acids (especially C16-C18), and hydrogenated castor oil.

[0044] In a particular embodiment of the present invention, when the composition comprises at least one or more fatty alcohols and one or more fatty acids as thickeners, the total weight of the fatty alcohols is greater than the total weight of the fatty acids.

[0045] According to a particular embodiment, when the composition according to the invention contains one or more fatty acids as thickener, it therefore also contains at least one fatty alcohol or hydrogenated castor oil.

[0046] By way of example, the composition according to the invention may contain one or more of the following as thickeners: cetearyl alcohol, for example O OR / MB marketed; behenyl alcohol, for example under the name 22; a mixture of stearic acid and palmitic acid, such as sold under the name Stearine TP 1200; hydrogenated castor oil, such as sold under the name HR sales.

[0047] In a particular embodiment of the invention, the composition comprises as cosmetically acceptable excipient at least one filler, which may be of mineral or organic origin.

[0048] Fillers of mineral origin that can be used in the composition according to the invention include clay, ceramic beads, calcium carbonate, titanium oxide, kaolin or aluminum silicate. Fillers of organic origin include starch, maltodextrin, cellulose (such as cellulose beads), microcrystalline cellulose, sodium carbonate, nylon microspheres, micronized or non-micronized plant-based powders (such as fruit powder or bamboo powder), or rice husk powder, and mixtures thereof.

[0049] The composition according to the invention preferably contains at least one filler selected from kaolin, maltodextrin, starch, cellulose, calcium carbonate and mixtures thereof.

[0050] The starch that can be used in the present invention can be obtained from plant sources such as cereals, tubers, roots, vegetables and fruits. For example, it can be corn starch, potato starch, pea starch, rice starch, oat starch, barley starch, cassava starch, wheat starch, tapioca starch or sorghum starch. These starches can be modified or unmodified. Modified starch is a starch that has been modified by methods known to those skilled in the art, such as esterification, etherification, oxidation, acid hydrolysis, crosslinking or enzymatic conversion. For example, it is possible to use starches such as those known under the name As cellulose, microcrystalline cellulose sold under the name CS 9FM can be used. For example, microcrystalline cellulose sold under the name CS 9FM by Imerys can be used. Kaolin sold by Opaque.

[0051] The total amount of fillers in the composition according to the invention is preferably comprised between 5 and 25% by weight, preferably between 5 and 20% by weight, for example between 15 and 20% by weight, relative to the total weight of the composition.

[0052] The composition according to the invention may contain one or more emollients chosen in particular from vegetable oils such as sunflower oil or sweet almond oil, fats such as shea butter, for example those sold under the name Lipex or SB 45 is marketed; lauroyl lysine, for example under the name Sold by LL; and glycerin.

[0053] The emollient content of the composition according to the invention is, for example, comprised between 2 and 20% by weight, in particular between 2 and 15% by weight, preferably between 2 and 10% by weight or between 5 and 15% by weight relative to the total weight of the composition.

[0054] In other particular embodiments of the invention, the emollient content of the composition according to the invention is less than 5% by weight relative to the total weight of the composition.

[0055] The composition according to the invention may also contain one or more pH regulators. It is preferably free of pH regulators, in particular pH regulators of the type NaOH, citric acid, lactic acid, etc.

[0056] Optionally, the composition according to the present invention may also contain: - one or more conditioning agents, which preferably do not belong to the class of cationic surfactants, in particular selected from isoamyl laurate, lauroyl lysine, a combination of chitosan and mandelic acid, erythritol, oleylglycerol (e.g. under the name OG), guar gum, polyglyceryl 4-caprate or any mixture thereof, the total amount of conditioning agent preferably comprised between 0.01% and 2% by weight, preferably between 0.05% and 1.5% by weight relative to the total weight of the composition; - and / or one or more stabilizers, such as chelating agents, for example tetrasodium glutamate diacetate, such as those known under the name GL-47-S, vitamin E or tocopheryl acetate, sold under the name T-90 for sale.

[0057] The composition according to the invention may contain one or more cosmetic active agents, in particular topical agents, chosen for example from moisturizers, antioxidants, vitamins and the like.

[0058] The total content of cosmetic active agents in the composition according to the invention may for example be comprised between 0.05% and 3% by weight relative to the total weight of the composition.

[0059] In a specific embodiment of the present invention, the composition comprises one or more cosmetic active agents selected from the group consisting of hyaluronic acid, oat extract, immortelle extract, immortelle essential oil, meadowfoam oil, in particular Limnanthes alba seed oil, oat seedlings, flower acids (such as Acides de products sold under the name of Edelweiss), cinchona extract, caffeine, peony extract, mango butter and citron extract, such list in no way limiting the present invention.

[0060] The composition according to the invention may also contain an exfoliant which will exfoliate the skin (including the scalp) by mechanical and / or chemical action, exfoliants acting both mechanically and chemically being particularly preferred within the scope of the invention. The exfoliant may be chosen from agents of mineral, vegetable or organic origin. Thus, it is possible to use, for example, polyethylene beads or powders, nylon granules, polyvinyl chloride powders, pumice stones (INCI name: pumice), walnut shells, sawdust, wood flour, cork flour, glass beads, alumina (aluminium oxide) (INCI name: Aluminium Oxide), sugar crystals, beads that melt when applied to the skin, such as spheres based on mannitol and cellulose, capsules based on agar, spheres based on jojoba esters, and mixtures thereof. The exfoliant used is preferably not water-soluble.

[0061] The composition according to the invention in its desired form can be prepared by any conventional method for preparing solid cosmetic compositions. Particularly preferred preparation methods within the scope of the present invention include extrusion and hot casting methods.

[0062] A method for preparing the composition according to the invention by extrusion comprises preparing a noodle containing the surfactant and excipients of the composition, and then adding any active agents and fragrances to the noodle. The mixture is then extruded through different screens to homogenize and refine it. Once the mixture is homogenous, it produces a soap bar, which is cut and shaped to obtain a solid composition in the desired shape.

[0063] A method for preparing a composition according to the invention by hot casting comprises mixing the ingredients of the composition and heating the resulting mixture to a temperature of about 75-80° C. The homogenized hot mixture is then poured into a mold of the desired shape and then allowed to cool.

[0064] Both preparation methods are easy and fast.

[0065] Another aspect of the present invention relates to the non-therapeutic cosmetic use of a solid cosmetic composition according to the invention for washing and / or caring for (including exfoliating) the skin, in particular the skin of the body and / or face and / or the scalp, and / or hair of an individual, preferably by topical application.

[0066] Such use preferably comprises the following consecutive steps: - moistening the composition with water, - foaming, in particular by rubbing the composition on a wet surface, - applying the foam to the skin and / or hair, which is preferably already pre-moistened, - and rinsed off, preferably with water, if necessary after leaving it on for a while and / or massaging.

[0067] These steps may be performed, for example, once to twice daily, such as in the morning and evening, or as often as desired.

[0068] The solid composition according to the invention can be used in particular for cleaning and / or caring for sensitive or atopic skin.

[0069] In this specification, sensitive skin is understood to mean skin that is susceptible to irritation or allergic reactions due to various internal and external non-immune factors. Atopic skin is understood to mean skin affected by inflammatory diseases characterized by dry, itchy skin, such as eczema or atopic dermatitis.

[0070] The present invention also relates to a non-therapeutic cosmetic treatment method for the hygiene and / or care of the skin and / or hair of an individual using the solid cosmetic composition according to the invention. The method comprises the following consecutive steps: - moistening the composition with water, - Foaming, - applying the foam to the skin and / or hair, - and rinse off, preferably with water.

[0071] This method may follow any feature or combination of features described above with respect to the cosmetic use of the composition according to the invention.

[0072] The features and advantages of the present invention will become more apparent from the following illustrative embodiments, which are provided by way of example only and in no way limit the present invention.

[0073] Examples

[0074] 1 / Examples of Compositions

[0075] The solid composition according to the invention intended for cosmetic treatments, for skin hygiene and care for the body and face has the characteristics listed in Table 1.

[0076] Composition 1 Composition 2 Composition 9 Ingredients (INCI name) %w / w %w / w %w / w Sodium Cocoyl Glutamate 15-20 25-30 5-10 Sodium myristoyl glutamate - - 5-10 Decyl Glucoside - 1.5 3 Lauryl Glucoside 3 - - Sodium lauroyl lactylate 3-6 3-6 3-6 Stearic acid / palmitic acid 7-10 7-10 7-10 Behenyl alcohol - - Appropriate amount up to 100 Cetearyl Alcohol Appropriate amount up to 100 Appropriate amount up to 100 - Hydrogenated Castor Oil 5-10 5-10 4 Sunflower Oil 11 5 2 Shea Butter 2 1 1 Kaolin - - - Corn starch 18 18 20 Tetrasodium Glutamate Diacetate - - - water 3 1.5 3

[0077] Table 1 - Examples of compositions according to the invention for skin hygiene and care of the body and face

[0078] The solid composition according to the invention intended for cosmetic treatments, for hair hygiene and care, has the characteristics listed in Table 2.

[0079] Composition 3 Composition 4 Composition 5 Ingredients (INCI name) %w / w %w / w %w / w Disodium Cocoyl Glutamate 25-30 - - Sodium Cocoyl Glutamate - 25-30 25-30 Decyl Glucoside 3 - - Lauryl Glucoside - 3 3 Sodium lauroyl lactylate 3-6 3-6 3-6 Stearic acid / palmitic acid Appropriate amount up to 100 7 7 Behenyl alcohol - Appropriate amount up to 100 - Cetearyl Alcohol - - Appropriate amount up to 100 Hydrogenated Castor Oil - 7 7 Coconut Oil 5 - - Sweet almond oil - 6 - Sunflower Oil - - 5 Shea Butter - - 1 Maltodextrin 6 - - Corn starch - 18 18 Tocopheryl acetate 0.05 - - water 3 3 3

[0080] Table 2 - Examples of compositions according to the invention for hair hygiene and care

[0081] The comparative solid composition not according to the invention has the characteristics listed in Table 3.

[0082]

[0083] Table 3 - Examples of compositions not according to the invention

[0084] More specifically, composition 6 contained no alkyl glucoside surfactants having a C8-C16 alkyl group, composition 7 contained a surfactant comprising an isethionate group and did not contain any acyl glutamate surfactants, and composition 8 contained no alkyl glucoside surfactants having a C8-C16 alkyl group but contained a mixture of arachidyl glucoside (C20 alkyl) and arachidyl alcohol in addition to behenyl alcohol.

[0085] 2 / Evaluation of composition characteristics

[0086] The composition of Example 1 was evaluated according to the following criteria: - Foaming properties (quality / quantity): foam height, fine foam, softness of foam, - good tolerance (physiological pH, hypoallergenic, softer and gentler on the skin), - stability over time, - organoleptic properties (color, smell), - Hardness, as measured by a texture analyzer; the composition must have sufficient consistency to prevent crumbling, but must not be too soft, - viscosity, as measured by a texture analyzer; the composition must have a sufficient degree of viscosity to prevent crumbling, but not too high to be pleasant to use and capable of being prepared under good conditions, especially in an extrusion device, pH: measured using a pH meter after diluting 1 g of composition in 100 g of water, in order to ensure that the pH indeed corresponds to the physiological pH of the skin.

[0087] To this end, the following operational scheme was implemented.

[0088] The hardness and stickiness were evaluated using a TA.XTplus texture analyzer with a penetration and withdrawal speed of 1 mm / s, a trigger force of 5 g, a distance of 8 mm and a Needle P / 2 N. The composition was fixed to the workbench of the texture analyzer and the following items were measured: the penetration force of the needle (a measure of hardness) and the withdrawal force of the needle (an evaluation of stickiness). The results are expressed in grams.

[0089] The height of the foam is assessed using a 250 ml graduated cylinder with an outer diameter of 38.9 cm and a height of 36 cm and a stopper. 0.5 g of the composition is placed in this graduated cylinder and demineralized water is added to make up to 50 ml. The graduated cylinder is capped and then shaken vigorously 10 times. The height of the foam is read and expressed in mm.

[0090] The results obtained are shown in Table 4 for the compositions according to the invention (Composition 1, Composition 2 and Composition 5) and for the comparative compositions not according to the invention (Composition 6, Composition 7 and Composition 8).

[0091] Composition 1 2 5 6 7 8 pH 5.35 5.35 5.38 5.41 4.94 - Foam height (mm) 42 52 31 22 26 - Hardness(g) 942 1378 1236 2524 1160 5995 Viscosity(g) -397 -406 -338 -988 -319 -1573

[0092] Table 4 -Characteristics of the composition

[0093] It can be seen that the three compositions according to the invention have greater foam heights compared to the foam heights of the compositions not according to the invention, and in particular composition 7 which contains an isethionate surfactant. The foaming characteristics of compositions 1 and 5, which have a total surfactant content of 23 or 24% w / w, are greater than the foaming characteristics of comparative compositions 6 and 7, which have a much higher surfactant content (30 or 32% w / w). Composition 2 according to the invention has a similar surfactant content (31.5% w / w) to the comparative compositions 6 and 7, and it can be seen that its foaming characteristics are much superior.

[0094] Furthermore, composition 6, which does not contain any C8-C16 alkyl glucoside surfactant, is more viscous and harder than the composition according to the invention. For composition 8, in which the C8-C16 alkyl glucoside surfactant is replaced by arachidyl glucoside, the hardness and stickiness are even greater.

[0095] In addition, the foam height of composition 9 according to the present invention was evaluated by the same method. A foam height of 45 mm was obtained, which was as satisfactory as the foam heights of compositions 1 and 2.

[0096] 3 / Comparative study of sensory profiles

[0097] Composition 10 according to the invention and composition 11 not according to the invention (made with non-natural ingredients such as disodium lauryl sulphosuccinate, sodium cocoyl isethionate and paraffin) having the compositions shown in Table 5 below were analysed for their sensory profiles.

[0098] Composition Composition 10 Composition 11 Ingredients (INCI name) %w / w %w / w Sodium Cocoyl Glutamate 10-15 - Decyl Glucoside 3 - Sodium lauroyl lactylate 3-6 - Disodium lauryl sulfosuccinate - 25-28 Sodium Cocoyl Isethionate - 18-20 Oat extract / juice 1 - Sodium Hyaluronate 0.1 - Sweet almond oil - 1.5 Palm Oil - 1 Stearic acid / palmitic acid 6-10 11-12 Behenyl alcohol Appropriate amount up to 100 - Cetearyl Alcohol - 2-3 Hydrogenated Castor Oil 3-6 - Sunflower Oil 3 - Shea Butter 1 - paraffin - 2-3 Maltodextrin - 18-19 Corn starch 18-20 - Tetrasodium Glutamate Diacetate - - water 3 7

[0099] Table 5 - Examples of compositions according to the invention for skin hygiene and care of the body and face, and comparative compositions.

[0100] After applying the composition 7 times to each wet arm, the sensory profile was evaluated individually by 15 trained panelists using descriptors specific to the 3 evaluation stages: - upon application (foam generation, quality and amount of foam, behavior of the product between the fingers: oily / sticky feeling), - When rinsed off (easy to rinse off), - As well as on dry skin 15 minutes after rinsing off (powdery feeling, skin elasticity, firmness, shine, residual film on the skin, oily / resistant / sticky feeling).

[0101] The conclusion of the test is as follows: The 2 compositions evaluated have very similar sensory characteristics. Even the composition according to the invention (composition 10) was found to be slightly less oily to the touch and to be easier to rinse off.

[0102] This evaluation shows that the composition according to the invention, which is more natural, achieves at least comparable results on the skin to the control composition comprising almost 50% of the isethionate / sulfosuccinate combination.

Claims

1. A solid cosmetic composition, characterized in that: The solid cosmetic composition comprises: - a mixture of surfactants comprising at least one anionic surfactant chosen from acyl glutamic acids and cosmetically acceptable salts thereof, at least one nonionic surfactant chosen from alkyl glucosides wherein the alkyl group contains from 8 to 16 carbon atoms, and at least one anionic surfactant chosen from acyl lactyl lactic acids and cosmetically acceptable salts thereof, - and at least one cosmetically acceptable excipient, The composition comprises less than 5% by weight of water relative to the total weight of the composition, and The composition is free of surfactants containing isethionic acid or isethionic acid groups and surfactants containing sulfosuccinic acid or sulfosuccinate groups.

2. The composition according to claim 1, wherein The content of the mixture of surfactants is comprised between 15 and 50% by weight relative to the total weight of the composition.

3. The composition according to claim 1 or 2, wherein The total content of nonionic surfactants chosen from alkyl glucosides wherein the alkyl group comprises from 8 to 16 carbon atoms is comprised between 1% and 5% by weight relative to the total weight of the composition.

4. The composition according to any one of claims 1 to 3, which is free of surfactants comprising sulfate groups.

5. The composition according to any one of claims 1 to 4, wherein The total content of anionic surfactants chosen from acylglutamic acids and cosmetically acceptable salts thereof is comprised between 50 and 80% by weight relative to the total weight of the mixture of surfactants.

6. The composition according to any one of claims 1 to 5, wherein The at least one nonionic surfactant is octyl glucoside, lauryl glucoside, decyl glucoside or a mixture thereof.

7. The composition according to any one of claims 1 to 6, wherein The at least one anionic surfactant selected from acyl glutamic acids and cosmetically acceptable salts thereof is selected from the group consisting of sodium cocoyl glutamate, disodium cocoyl glutamate, sodium myristoyl glutamate, sodium lauroyl glutamate, potassium lauroyl glutamate, potassium cocoyl glutamate, sodium stearoyl glutamate, and any mixtures thereof.

8. The composition according to any one of claims 1 to 7, wherein The at least one anionic surfactant selected from acyl lactylic acid and cosmetically acceptable salts thereof is sodium lauroyl lactylate, sodium stearoyl lactylate or a mixture thereof.

9. The composition according to any one of claims 1 to 8, which is free of amphoteric surfactants.

10. The composition according to any one of claims 1 to 9, wherein The at least one cosmetically acceptable excipient is selected from the group consisting of thickeners, fillers, emollients, conditioning agents, stabilizers, fragrances and mixtures thereof.

11. The composition according to claim 10, comprising at least one filler selected from the group consisting of kaolin, maltodextrin, starch, cellulose, calcium carbonate and mixtures thereof.

12. Composition according to claim 10 or 11, comprising a total amount of fillers comprised between 5 and 25% by weight relative to the total weight of the composition.

13. The composition according to any one of claims 10 to 12, containing a total amount of consistency agent comprised between 25% and 65% by weight relative to the total weight of the composition.

14. A composition according to any one of claims 1 to 13 further comprising an exfoliating agent.

15. A composition according to any one of claims 1 to 14, comprising at least one cosmetic active agent selected from the group consisting of hyaluronic acid, oatmeal extract, immortelle extract, immortelle essential oil, meadowfoam seed oil, oat seedlings, flower acid, garcinia extract, milk thistle oil, niacinamide, edelweiss extract, cinchona extract, caffeine, peony extract, mango butter and citron extract.

16. The composition according to any one of claims 1 to 15, which is packaged in the form of rectangular sticks, round sticks, bars or balls.

17. Non-therapeutic cosmetic use of a composition according to any one of claims 1 to 16 for washing and / or caring for the skin and / or hair.

18. The use according to claim 17 for cleaning and / or caring for sensitive skin.

19. A non-therapeutic cosmetic treatment method for the hygiene and / or care of the skin and / or hair with the aid of a composition according to any one of claims 1 to 16, said method comprising the following successive steps: - wetting the composition with water, - Foaming, - applying said foam to said skin and / or hair, - and rinse off.

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