Method for crosslinking polysaccharides in concentrated aqueous-organic media and topical formulations comprising the same

Abstract

The present invention relates to a novel process for crosslinking polysaccharides of natural origin in an aqueous-organic medium and topical formulations comprising the same. The process of the present invention produces gels of natural origin polymers more concentrated or free of added water and in powder form, suitable for thickening, stabilizing or emulsifying cosmetic or pharmaceutical topical formulations or for suspending solid particles therein.

Description

Technical Field

[0001] This invention pertains to the fields of cosmetics and pharmaceuticals. More particularly, this invention relates to a novel method for synthesizing thickeners of natural origin. Background Technology

[0002] Polymers are currently widely used in topical formulations in the fields of cosmetics, dermocosmetics, pharmacy, and dermopharmacy. Most of them are rheology modifiers that thicken polar phases (such as water).

[0003] Examples of such polymers include cross-linked polyelectrolytes, which possess the ability to unfold in polar solvents, particularly due to electrostatic repulsion arising from the presence of charges on their polymer backbone. This phenomenon allows for the formation of polymer networks that result in increased viscosity, consistency, and stabilization of formulations such as oil-in-water or water-in-oil emulsions in the presence or absence of emulsifying surfactants, or gel-creams without emulsifying surfactants. These polymers are typically produced by the polymerization of acrylate or methacrylate monomers or monomers derived from acrylamide or its derivatives.

[0004] Examples of commercially available or literature-disclosed crosslinked polymeric electrolytes include: - Homopolymers of acrylic acid partially or fully salted with sodium, ammonium, or potassium salts; homopolymers of methacrylic acid partially or fully salted with sodium, ammonium, or potassium salts; homopolymers of 2-methyl-((1-oxo-2-propenyl)amino)-1-propanesulfonic acid (AMPS) partially or fully salted with sodium, ammonium, or potassium salts. - Copolymers of acrylic acid and AMPS that are partially or fully salted with sodium, ammonium, or potassium salts; copolymers of methacrylic acid and AMPS that are partially or fully salted with sodium, ammonium, or potassium salts. - A copolymer of acrylamide and AMPS that are partially or completely salted with sodium, ammonium, or potassium salts. - A copolymer of vinylpyrrolidone and AMPS partially or completely salted with sodium, ammonium or potassium salts. - A copolymer of AMPS that are partially or completely salted with sodium, ammonium, or potassium salts and 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate, or 2,3-dihydroxypropyl acrylate or 2,3-dihydroxypropyl methacrylate. - A copolymer of AMPS that is partially or completely salted with sodium, ammonium, or potassium salts and hydroxyethyl acrylamide or hydroxyethyl methyl acrylamide. - A copolymer of AMPS partially or completely salted with sodium, ammonium, or potassium salts and N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N,N-diethylacrylamide, N,N-diethylmethacrylamide, N-methylacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-(tert-butyl)acrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N-propylmethacrylamide, N-isopropylmethacrylamide, N-butylacrylamide, N-(tert-butyl)acrylamide, or N,N-dipropylacrylamide. - A copolymer of AMPS and tris(hydroxymethyl)acrylamidomethane (THAM) that is partially or completely salted with sodium, ammonium, or potassium salts. - A copolymer of acrylic acid or methacrylic acid and (2-hydroxyethyl) acrylate or (2,3-dihydroxypropyl) acrylate, partially or completely salted with sodium, ammonium or potassium salts. - A copolymer of acrylic acid or methacrylic acid and (2-hydroxyethyl) methacrylate or (2,3-dihydroxypropyl) methacrylate, partially or completely salted with sodium, ammonium or potassium salts. - A copolymer of acrylic acid or methacrylic acid and hydroxyethylacrylamide, which is partially or completely salted with sodium, ammonium, or potassium salts. - A copolymer of acrylic acid or methacrylic acid and THAM, partially or completely salted with sodium, ammonium, or potassium salts. - Copolymers of acrylic acid or methacrylic acid partially or completely salted with sodium, ammonium, or potassium salts and N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N,N-diethylacrylamide, N,N-diethylmethacrylamide, N-methacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-(tert-butyl)acrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N-propylmethacrylamide, N-isopropylmethacrylamide, N-butylacrylamide, N-(tert-butyl)methacrylamide, or N,N-dipropylacrylamide. - Branched or crosslinked terpolymers of acrylic acid or methacrylic acid partially or completely salted with sodium, ammonium or potassium salts, AMPS partially or completely salted with sodium, ammonium or potassium salts, and (2-hydroxyethyl) acrylate or (2-hydroxyethyl) methacrylate, or (2,3-dihydroxypropyl) acrylate or (2,3-dihydroxypropyl) methacrylate. - Branched or cross-linked terpolymers of acrylic acid or methacrylic acid partially or fully salted with sodium, ammonium or potassium salts, and AMPS and THAM partially or fully salted with sodium, ammonium or potassium salts. - Branched or crosslinked terpolymers of acrylic acid or methacrylic acid partially or completely salted with sodium, ammonium, or potassium salts; AMPS and N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N,N-diethylacrylamide, N,N-diethylmethacrylamide, N-methacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-(tert-butyl)acrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N-propylmethacrylamide, N-isopropylmethacrylamide, N-butylacrylamide, N-(tert-butyl)acrylamide, or N,N-dipropylacrylamide. - Branched or crosslinked terpolymers of acrylic acid or methacrylic acid partially or fully salted with sodium, ammonium or potassium salts, and AMPS and acrylamide or methacrylamide partially or fully salted with sodium, ammonium or potassium salts. - Acrylic acid or methacrylic acid partially or fully salted with sodium, ammonium, or potassium salts and copolymers of alkyl acrylates or alkyl methacrylates wherein the carbon chain contains 4 to 30 carbon atoms, more particularly 10 to 30 carbon atoms, and - A copolymer of AMPS that are partially or completely salted with sodium, ammonium or potassium salts and alkyl acrylates or alkyl methacrylates in which the carbon chain contains 4 to 30 carbon atoms, more particularly 10 to 30 carbon atoms.

[0005] These polymers, whether in the form of self-invertible inverse latices, concentrated inverse latices, or powders, now make it possible to meet customer demands for thickening properties in polar solvents such as water. Aqueous gels obtained by dispersing them in such solvents have a smooth appearance, are free of particles or lumps, possess specific tactile properties, and are also easy to manipulate and apply to the skin.

[0006] Despite ample commercial supply, novel thickeners for the aqueous phase remain essential for the formulation of cosmetic and dermatological pharmaceutical products because the polymers currently used are primarily petrochemically derived, while user industries are keen on eco-design processes. Therefore, there is a need to develop alternative thickeners that, while possessing comparable properties, offer improved environmental characteristics due to their origin or the source of their precursors, or due to their biodegradability. The use of polysaccharides appears to be an acceptable alternative, as they have been industrially used for many years as texture or rheology modifiers in the preparation of pharmaceuticals, cosmetics, or food products.

[0007] Depending on their chemical composition, they can be used as gelling agents or thickeners. The term "thickening agent" refers to a chemical compound that increases the viscosity of the medium to which it is introduced. The term "gelling agent" refers to a compound that transforms a liquid medium into a non-flowing, structured state by forming a three-dimensional network within the liquid; gels are considered an intermediate state between liquid and solid.

[0008] Polysaccharides are polymers of saccharides, or more commonly, polymers of sugars. According to the nomenclature of the International Union of Pure and Applied Chemistry (IUPAC), sugars refer to monosaccharides, monosaccharide compounds themselves, and their derivatives, obtained through the reduction of a carbonyl group, the oxidation of one or more hydroxyl functional groups, or the substitution of one or more hydroxyl functional groups with hydrogen atoms or amine, phosphate, or sulfate functional groups.

[0009] The polysaccharides most commonly used in the aforementioned industries are polymers of monomer units containing monosaccharides such as glucose, galactose, mannose, xylose, arabinose, or monosaccharide derivatives in which the hydroxyl functional group of the terminal carbon has been oxidized to a carboxyl functional group.

[0010] Polysaccharides, which are composed entirely of monosaccharides, specifically include: - Starch and starch derivatives are homopolymers of glucose with alpha-1,4 glycosidic linkages; distinguished from linear homopolymers called amylose (approximately 20% of starch, consisting only of alpha-1,4 linkages) and branched homopolymers called amylopectin (approximately 80% of starch, consisting of both alpha-1,4 and alpha-1,6 glycosidic linkages). Starch is obtained from plants such as wheat, corn, or potatoes.

[0011] - Cellulose, which is a homopolymer of glucose with β-1,4 glycosidic bonds; cellulose is extracted from wood and is mainly used in the paper industry to make pulp.

[0012] - Hemicellulose is a polymer of different sugars such as glucose, mannose, galactose, xylose, arabinose, and rhamnose, with xylose usually being the main component. Hemicellulose sometimes also contains uronic acid.

[0013] Polysaccharides composed of monosaccharide derivatives particularly include: - Sulfated galactans are polymers of galactose that may have sulfate ester side groups, such as algal polysaccharides or agar. - uronans are polymers of uronic acids, such as alginate and pectins. - Heteropolymers of monosaccharides, including galactomannans such as guar gum, tara gum, carob gum, and fenugreek gum, and glucomannoglycans such as konjac gum; and - Xyloglycans, such as tamarind gum. - Polymers of monosaccharides and uronic acids; these polymers are particularly found in sap exudates, such as gum arabic and karaya gum; they are also produced by microorganisms, such as xanthan gum and gellan gum. - Glucosaminoglycans: These are polysaccharides formed from glucose by replacing its C-2 hydroxyl group with an amine functional group (called 2-amino-2-deoxy-D-glucose or glucosamine); the amine functional group can be acetylated. This class of polysaccharides includes chitosan, which is formed entirely of glucosamine units; chitin, which has acetylated amino functional groups; and hyaluronan, in which the repeating unit is a dimer of glucosamine and glucuronic acid.

[0014] Chemical modification of polysaccharides is one way to improve their initial properties and provide new characteristics. This involves chemical functionalization, or cross-linking, by grafting new chemical groups with higher or lower molecular weights. This includes combining polysaccharide chains with each other using at least a bifunctional crosslinking agent called a crosslinker. In both cases, the functional groups of the starting polysaccharide involved retain hydroxyl (monosaccharides), amino (glucosamine derivatives), or carboxyl (uronic acid derivatives).

[0015] However, such functionalization is often carried out using reagents that are not very eco-friendly or through procedures that only partially comply with the twelve principles of green chemistry, such as the use of organic solvents. Furthermore, the resulting products currently cannot compete with commercially available thickening polymers from petrochemical sources in terms of thickening or gelling properties.

[0016] Among the crosslinking agents commonly used for crosslinking natural polysaccharides, only those belonging to the polyphosphate derivative category, such as sodium trimetaphosphate (STMP) or sodium tripolyphosphate (STPP), are of interest from an environmental perspective. STMP is a non-toxic compound to humans and is commonly used in the food and pharmaceutical industries; it is synthesized by the high-temperature dehydration of sodium polyphosphate; it is partially soluble in cold water, very poorly soluble in hot water, and insoluble in methanol, diethyl ether, n-octanol, or acetone. Polysaccharide crosslinking using STMP, as described in patents or academic literature, is carried out in an aqueous medium under alkaline pH conditions at temperatures ranging from 20°C to 50°C for several hours.

[0017] However, the crosslinking methods used to date yield highly diluted crosslinked natural polymer gels, specifically containing approximately 3% by mass of the crosslinked polymer. Such dilution makes it impossible to prepare crosslinked natural polysaccharides in powder form on an industrial scale. On the other hand, the commercialization of such hydrogels (i.e., solutions containing water and 3% or 5% by mass of crosslinked polysaccharides) requires the use of preservatives, which is effectively imposed on formulators of topical cosmetic or pharmaceutical compositions and may prove incompatible with specific preservative systems in said topical compositions. Therefore, there is a need to develop crosslinking methods that produce more concentrated or additive-free water-free, naturally derived polymer gels in powder form. Summary of the Invention

[0018] Therefore, according to the first aspect, one subject of the present invention is a method for preparing at least one cross-linked polysaccharide, comprising the following steps: - Step a), preparing a water-polar solvent mixture, wherein the polar solvent is selected from aliphatic alcohols containing 1 to 4 carbon atoms, ketones containing 3 to 5 carbon atoms, and polyols containing 2 or 3 hydroxyl groups and 2 to 6 carbon atoms, wherein the preparation is carried out by mixing water and the polar solvent in a mass ratio of the polar solvent to water greater than or equal to 0.4 and less than or equal to 19.0. - Step b) dispersing at least one polysaccharide in the water-polar solvent mixture prepared in step a) to obtain a reaction medium comprising, by weight, a polysaccharide mass percentage greater than 10% and less than or equal to 55%; the at least one polysaccharide used in step b) is selected from xanthan gum, xanthan gum with hydrocarbon branches containing 2 to 22 carbon atoms, more particularly xanthan gum esterified with dodecanoate, guar gum and konjac gum, carrageenan, more particularly the group consisting of kappa-carrageenan and iota-carrageenan, and mixtures of two or more of the polysaccharides in the group; - Step c), adjusting the pH of the reaction medium prepared in step b) to a value greater than or equal to 8.0 and less than or equal to 13.0, more particularly greater than or equal to 8.5 and less than or equal to 12.5 by adding alkali; - Step d), crosslinking the at least one polysaccharide by adding a phosphate crosslinking agent selected from sodium trimetaphosphate (STMP) and sodium tripolyphosphate (STPP) to the alkaline reaction medium obtained at the end of step c), to obtain an alkaline dispersion containing the crosslinked polysaccharide; - Step e), adjust the pH of the alkaline dispersion obtained at the end of step d) to a value less than or equal to 7.0 to obtain a non-alkaline dispersion of the cross-linked polysaccharide; - Step f), filtering the non-alkaline dispersion obtained at the end of step e) to recover the at least one intended cross-linked polysaccharide therefrom; optionally thereafter: - Step g), drying to remove trace amounts of residual solvent. - or step h), atomize the at least one cross-linked polysaccharide obtained in step f) to obtain a powder therefrom.

[0019] According to a specific aspect of the method defined above, steps a) and b) are simultaneous and constitute a single step A), namely, the preparation of the reaction medium by mixing water, a polar solvent selected from aliphatic alcohols containing 1 to 4 carbon atoms, ketones containing 3 to 5 carbon atoms, and polyols containing 2 or 3 hydroxyl groups and 2 to 6 carbon atoms, and a polysaccharide, in proportions such that: - The mass percentage of the at least one polysaccharide is greater than 10% by mass and less than or equal to 55% by mass of the reaction medium, and - The mass ratio of the polar solvent to water in the mixture is greater than or equal to 0.4 and less than or equal to 19.0.

[0020] In the method defined above, the polar solvent of the mixture prepared in step a) or the polar solvent of the reaction medium prepared in step A) is more particularly selected from methanol, ethanol, butanol, isopropanol, acetone, methyl ethyl ketone (MEK), glycerol, 1,3-propanediol, butylene glycol, 1,3-butanediol, pentylene glycol, hexylene glycol, and 2-methyl-2,4-pentanediol; according to this particular embodiment, the polar solvent is most particularly selected from ethanol and isopropanol.

[0021] In the method defined above, one or more salts may be optionally added during the preparation of the water-solvent mixture prepared in step a) or the reaction medium prepared in step A), such as salts selected from sodium chloride, calcium chloride, magnesium chloride, calcium sulfate, magnesium sulfate, calcium carbonate, magnesium carbonate, magnesium aspartate, and other monovalent or divalent salts acceptable in the cosmetic, pharmaceutical, plant health, or food industries.

[0022] In the method defined above, the mass ratio of polar solvent to water in the mixture prepared in step a) or the reaction medium prepared in step A) is particularly greater than or equal to 1.0 and less than or equal to 4.0.

[0023] In the method defined above, the reaction medium prepared in step b) or step A) more particularly comprises, by weight 15% and less than 45% of the mass of the at least one polysaccharide, as 100% of its mass.

[0024] According to a particular aspect of the invention, if necessary, step b) of dissolving or dispersing the at least one polysaccharide or step A) of preparing the reaction medium is carried out at a temperature between 50°C and 100°C, preferably between 60°C and 80°C.

[0025] In the method defined above, step c) is carried out by adding an alkaline base, such as sodium hydroxide or potassium hydroxide, ammonia, or an amine base, to the reaction mixture prepared in step b) or step A). ​​Sodium hydroxide, particularly a tetramolar aqueous solution, potassium hydroxide, ammonia, or triethylamine is used more specifically. In the method defined above, in step c), the pH is more specifically adjusted to a value greater than or equal to 10.0 and less than or equal to 12.5.

[0026] In the method defined above, the mass ratio of the STMP or STPP crosslinking agent used in step d) to the at least one starting polysaccharide is greater than or equal to 0.0001 and less than or equal to 0.0700; more particularly, it is greater than or equal to 0.0003 and less than or equal to 0.0300. The crosslinking temperature can be between 5°C and 100°C, preferably between 10°C and 80°C, and ideally varies between 20°C and 70°C.

[0027] According to another specific implementation of the method defined above, the crosslinking agent used in step d) is sodium tripolyphosphate (STMP).

[0028] In the method defined above, step e) of adjusting the pH is specifically carried out using a strong acid, such as hydrochloric acid or sulfuric acid, to stop the cross-linking mechanism. This is typically done at an ambient temperature between 15°C and 35°C.

[0029] The methods defined above enable the production of polysaccharide gels in more concentrated or even solid forms, which allows them to be used industrially as an alternative to petroleum-derived polymers in dermocosmetics and dermopharmacy.

[0030] Therefore, a further subject of the present invention is the use of cross-linked polysaccharides or mixtures of cross-linked polysaccharides obtained by the methods defined above for thickening, stabilizing, or emulsifying cosmetic or pharmaceutical topical formulations. A further subject is the use of cross-linked polysaccharides obtained by the methods defined above for suspending solid particles in cosmetic or pharmaceutical topical formulations.

[0031] Therefore, a further subject of the present invention is a cosmetic or pharmaceutical topical formulation characterized in that it comprises, by weight of 0.1% to 10.0%, more particularly 0.5% to 5.0%, of a cross-linked polysaccharide or a mixture of cross-linked polysaccharides obtained by the methods defined above as a thickener, stabilizer or emulsifier of the cosmetic or pharmaceutical topical formulation, or as a reagent capable of and intended to suspend solid particles within the cosmetic or pharmaceutical topical formulation.

[0032] Solid particles suspended in cosmetic or pharmaceutical topical formulations, which are the subject of the uses or inventions defined above, have regular or irregular geometry and are typically in the form of pearls, beads, rods, scales, leaflets, or polyhedra. They are characterized by an average apparent diameter between 1 micrometer and 5 millimeters, and more particularly between 10 micrometers and 1 millimeter. Examples of such solid particles include mica, iron oxides, titanium oxides, zinc oxides, aluminum oxides, talc, silica, kaolin, clay, boron nitride, calcium carbonate, magnesium carbonate, magnesium bicarbonate, inorganic colored pigments, polyamides such as nylon-6, polyethylene, polypropylene, polystyrene, polyesters, acrylic or methacrylic polymers such as polymethyl methacrylate, polytetrafluoroethylene, crystalline or microcrystalline waxes, porous spheres, selenium sulfide, zinc pyrithione, starch, alginate, plant fibers, loofah particles, and sponge particles.

[0033] In cosmetic or pharmaceutical topical formulations that are the subject of the use or invention as defined above, the adjective "topical" means the formulation is used by application to the skin, hair, scalp or mucous membranes, whether by direct application or by indirect application by impregnating the topical composition according to the invention onto a carrier (paper, wipe, textile, transdermal device, etc.) intended to come into contact with the skin.

[0034] Cosmetic or pharmaceutical topical formulations used for the purposes or subject of the invention as defined above can be in any physical form, such as aqueous, aqueous-alcoholic, or aqueous-glycolic gels; solutions; powders; suspensions; or emulsions, microemulsions, or nanoemulsions, whether of the water-in-oil, oil-in-water, oil-in-water, or water-in-oil type. They can be packaged in bottles, in pump-action bottles, in aerosol devices under pressure, in devices equipped with perforated walls, such as grids, or in devices equipped with ball applicators (referred to as "roll-ons").

[0035] Generally, cosmetic or pharmaceutical formulations used for the purposes or subject of the invention as defined above may also contain one or more pharmaceutically or cosmetically acceptable ingredients, whether active ingredients or excipients, such as foaming, non-foaming or detergent surfactants, thickeners or gelling agents, stabilizers, solubilizers, film-forming compounds, solvents and cosolvents, water-soluble aids, spring water or mineral water, plasticizers, emulsifiers and co-emulsifiers, opacifiers, nacreous agents, superfatting agents, sequestrants, chelating agents, oils, waxes, antioxidants, fragrances, essential oils, preservatives, conditioning agents, deodorants, whitening agents intended to bleach body hair and skin, active ingredients intended to provide therapeutic or protective effects on skin or hair, sunscreens, mineral fillers or pigments, particles that provide visual effects or are intended to encapsulate active agents, exfoliating particles, texture-regulating agents, fluorescent whitening agents, or insect repellents.

[0036] The term "cosmetically acceptable" used in the definition of the above ingredients means, according to European Economic Community Council Directive No. 76 / 768 / EEC of July 27, 1976, as amended by Directive No. 93 / 35 / EEC of 14 June 1993, the excipients (E) include water and any substance or preparation intended to come into contact with various parts of the human body (epidermis, body hair and hair system, nails, lips and genitals) or with the teeth and oral mucosa, for the purpose of cleansing them, flavoring them, altering their appearance and / or correcting their odor and / or protecting them or keeping them in good condition.

[0037] The term "pharmaceutically acceptable" used in the definition of the above ingredients means that these ingredients are listed in the pharmacopoeia of the country where the formulation is used.

[0038] Examples of foaming surfactants that may be present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above include anionic, cationic, amphoteric, or nonionic foaming or detergent surfactants.

[0039] The foaming anionic surfactants that may be mentioned include the following alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts, or amino alcohols: - Alkyl ether sulfates, such as C12-14 myristole sodium sulfate containing 3.5 moles of ethylene oxide, C12-14 dodecyl ether sodium sulfate containing 2 moles of ethylene oxide, C12-14 dodecyl ether ammonium sulfate containing 2 moles of ethylene oxide, monoisopropylamine C12-14 dodecyl ether sulfate in propylene glycol containing 2 moles of ethylene oxide, triisopropylamine C12-14 dodecyl ether sulfate in propylene glycol containing 2 moles of ethylene oxide, C12-14 dodecyl ether sodium sulfate containing 3 moles of ethylene oxide, etc. C12-14 dodecyl ether ammonium sulfate in ethane, C12-15 dodecyl ether sodium sulfate containing 3 moles of ethylene oxide, C8-10 dodecyl ether sodium sulfate containing 3 moles of ethylene oxide, C8-10 dodecyl ether ammonium sulfate containing 3 moles of ethylene oxide, C9-11 dodecyl ether sodium sulfate containing 2.5 moles of ethylene oxide, C9-11 dodecyl ether ammonium sulfate containing 2.5 moles of ethylene oxide, and C9-11 dodecyl ether ammonium sulfate in hexanediol containing 2.5 moles of ethylene oxide; - Alkyl sulfates, such as sodium dodecyl sulfate, potassium dodecyl sulfate, ammonium dodecyl sulfate, magnesium dodecyl sulfate, sodium cocoyl sulfate, potassium cocoyl sulfate, ammonium cocoyl sulfate, and magnesium cocoyl sulfate; - Alkyl amide ether sulfates, alkyl aryl polyether sulfates, monoglyceride sulfates, α-olefin sulfonates, alkane sulfonates; - Alkyl phosphates, alkyl ether phosphates, alkyl sulfonates, alkyl amide sulfonates, alkyl aryl sulfonates, alkyl carboxylates, alkyl sulfosuccinates, alkyl ether sulfosuccinates, alkyl amide sulfosuccinates, alkyl sulfosuccinates; - N-acyl derivatives of amino acids, such as sodium lauroyl sarcosinate, potassium lauroyl sarcosinate, magnesium lauroyl sarcosinate, ammonium lauroyl sarcosinate, sodium lauroyl glycinate, potassium lauroyl glycinate, magnesium lauroyl glycinate, ammonium lauroyl glycinate, sodium cocoyl sarcosinate, potassium cocoyl sarcosinate, magnesium cocoyl sarcosinate, ammonium cocoyl sarcosinate, sodium cocoyl glycinate, potassium cocoyl glycinate, magnesium cocoyl glycinate, ammonium cocoyl glycinate, sodium cocoyl glutamate, potassium cocoyl glutamate, magnesium cocoyl glutamate, ammonium cocoyl glutamate, sodium cocoyl aspartate. aspartate), potassium cocoyl aspartate, magnesium cocoyl aspartate, ammonium cocoyl aspartate; or a mixture containing N-acyl derivatives of the said amino acids, such as those under the trade name Proteol TM OAT, Proteol TM APL, Oramix TM Those L30s that were sold; - Acyl isethionate, such as sodium cocoyl hydroxyethyl sulfonate, potassium cocoyl hydroxyethyl sulfonate, magnesium cocoyl hydroxyethyl sulfonate, ammonium cocoyl hydroxyethyl sulfonate, sodium lauroyl hydroxyethyl sulfonate, potassium lauroyl hydroxyethyl sulfonate, magnesium lauroyl hydroxyethyl sulfonate, and ammonium lauroyl hydroxyethyl sulfonate; - N-acyl taurate, such as sodium methylcocoyl taurate, potassium methylcocoyl taurate, magnesium methylcocoyl taurate, ammonium methylcocoyl taurate, or - Acyl lactylate.

[0040] In foaming amphoteric surfactants, the following can be mentioned: - Alkyl betaine, such as lauryl betaine, cocoyl betaine, and myristyl betaine; - Alkylamido betaines, such as lauramidopropyl betaine, cocamidopropyl betaine sodium salt, 1-propanaminium, 3-amino-N-(carboxymethyl)-N,N-dimethyl-, or under the trade name Amonyl TM Compositions sold by 380 BA; - Sultaine, alkylamide alkyl sulfonyl betaine, or as trade name Amonyl TMCompositions sold by 675 SB, or - Imidazoline derivatives, phosphobetaines, amphoteric polyacetates, and amphoteric propionates.

[0041] Among foaming cationic surfactants, quaternary ammonium derivatives deserve special mention.

[0042] Among foaming nonionic surfactants, more specifically mentioned are alkyl polyglycosides comprising linear or branched, saturated or unsaturated aliphatic groups, including 8 to 16 carbon atoms, such as n-octyl polyglucoside, n-decyl polyglucoside, n-undecenyl polyglucoside, n-dodecyl polyglucoside, n-tetradecyl polyglucoside, n-hexadecyl polyglucoside, and 1,12-dodecadiyl polyglucoside; ethoxylated hydrogenated castor oil derivatives, such as products sold under the INCI name "PEG-40 hydrogenated castor oil"; polysorbates, such as polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 70, polysorbate 80, or polysorbate 85; cocoamide; and N-alkylamines.

[0043] Examples of possible thickeners or gelling agents optionally present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above include: - Optional alkoxylated alkyl polyglycoside fatty acid esters, such as ethoxylated methyl polyglucoside esters, for example PEG 120 methyl glucoside trioleate and PEG 120 methyl glucoside dioleate, sold under the names Glucamate™ LT and Glucamate™ DOE120, respectively. - Alkoxylated fatty acid esters, such as PEG 150 pentaerythritol tetrastearate sold under the name Crothix™ DS53. - PEG 55 propylene glycol oleate sold under the name ANTIL™ 141, - Fatty-chain polyalkylene glycolcarbamates, such as PPG-14 laureth isophoryl dicarbamate sold under the name Elfacos™ T211 or PPG-14 palmeth-60 hexyl dicarbamate sold under the name Elfacos™ GT2125. - Cellulose and cellulose derivatives, such as methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose, - Starch, hydrophilic starch derivatives, - Polyurethane, - Silicates and phyllosilicates, such as aluminum silicate, magnesium, aluminum or magnesium silicate, kaolinite, montmorillonite, illite, beidellite, saponite, bentonite, hectorite, vermiculite, serpentine, nacrite, amesite, nontronite, lizardite, sericite, halloysite, muscovite, paragonite, damouzite, glauconite or celadonite; - Branched or crosslinked, anionic, cationic, or amphoteric polymeric electrolytes, such as branched or crosslinked homopolymers of acrylic acid, methacrylic acid, or 2-methyl-[(1-oxo-2-propenyl)amino]-1-propanesulfonic acid (AMPS) partially or fully salted with sodium, ammonium, or potassium salts; copolymers of acrylic acid or methacrylic acid partially or fully salted with sodium, ammonium, or potassium salts and AMPS partially or fully salted with sodium, ammonium, or potassium salts; branched or crosslinked copolymers of acrylamide or vinylpyrrolidone and AMPS partially or fully salted with sodium, ammonium, or potassium salts; and AMPS partially or fully salted with sodium, ammonium, or potassium salts and acrylic acid. 2-Hydroxyethyl acrylate, 2-Hydroxyethyl methacrylate, 2,3-Dihydroxypropyl acrylate or 2,3-Dihydroxypropyl methacrylate, hydroxyethyl acrylamide, hydroxyethyl methacrylamide, N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N,N-diethylacrylamide, N,N-diethylmethacrylamide, N-methylacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-(tert-butyl)acrylamide, N-methylmethacrylamide, N-ethylmethacrylamide N-propylmethacrylamide, N-isopropylmethacrylamide, N-butylmethacrylamide, N-(tert-butyl)methacrylamide, N,N-dipropylacrylamide, or branched or crosslinked copolymers of tris(hydroxymethyl)acrylammonium (THAM); acrylic acid or methacrylic acid partially or completely salted with sodium, ammonium, or potassium salts, and (2-hydroxyethyl) acrylate, (2-hydroxyethyl) methacrylate, (2,3-dihydroxypropyl) acrylate, (2,3-dihydroxypropyl) methacrylate, hydroxyethylacrylamide, hydroxyethylmethacrylamide, N,N-dimethylacrylamide, N, Branched or crosslinked copolymers of N-dimethylmethacrylamide, N,N-diethylacrylamide, N,N-diethylmethacrylamide, N-methacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-(tert-butyl)acrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N-propylmethacrylamide, N-isopropylmethacrylamide, N-butylmethacrylamide, N-(tert-butyl)methacrylamide, N,N-dipropylacrylamide, or tris(hydroxymethyl)acrylamidomethylmethane (THAM);Acrylic acid or methacrylic acid partially or completely salted with sodium, ammonium or potassium salts; AMPS partially or completely salted with sodium, ammonium or potassium salts; (2-hydroxyethyl) acrylate; (2-hydroxyethyl) methacrylate; (2,3-dihydroxypropyl) acrylate; (2,3-dihydroxypropyl) methacrylate; hydroxyethyl acrylamide; hydroxyethyl methacrylamide; N,N-dimethylacrylamide; N,N-dimethylmethacrylamide; N,N-diethylacrylamide; N,N-diethylmethacrylamide; N-methacrylamide; N-ethylacrylamide; N-propylacrylamide; N-isopropylacrylamide; N-butylacrylamide; N-(tert-butyl)acrylamide; N-methylmethacrylamide; N-ethylmethacrylamide Amines, N-propylmethacrylamide, N-isopropylmethacrylamide, N-butylmethacrylamide, N-(tert-butyl)methacrylamide, N,N-dipropylacrylamide, and tris(hydroxymethyl)acrylamidomethyl (THAM) branched or cross-linked terpolymers; acrylamide or methacrylamide; acrylic acid, methacrylic acid, or AMPS partially or fully salted with sodium, ammonium, or potassium salts and branched or cross-linked copolymers of alkyl acrylates or alkyl methacrylates wherein the carbon chain comprises 4 to 30 carbon atoms, more particularly 10 to 30 carbon atoms; AMPS partially or fully salted with sodium, ammonium, or potassium salts with at least one neutral monomer and at least one of the formula CH2=C(R'3)-C(=O)-[CH2-CH2-O]; n-R' is a branched or cross-linked terpolymer of monomers, wherein R'3 represents a hydrogen atom or methyl group, R'4 represents a linear or branched, saturated or unsaturated alkyl group containing 8 to 30 carbon atoms, more particularly selected from octyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, 2-ethylhexyl, 2-propylheptyl, 2-butyloctyl, 2-pentylnonyl, 2-hexyldecyl, 2-octyldodecyl, 4-methylpentyl, 5-methylhexyl, 6-methylheptyl, 15-methylpentadecanyl, 16-methylheptadecanyl, 2-hexyloctyl, 2-octyldecyl, or 2-hexyldodecyl, and n represents a number greater than or equal to 1 and less than or equal to 50; the homopolymer is: N,N,N-trimethyl-3-[(2-methyl-1-oxo-2-propenyl)amino] Propranium, N,N,N-trimethyl-3-[(1-oxo-2-propenyl)amino]propanium, diallyl dimethylammonium, N,N,N-trimethyl-2-[(2-methyl-1-oxo-2-propenyl)]ethylammonium, and more particularly N,N,N-trimethyl-3-[(2-methyl-1-oxo-2-propenyl)amino]propanium chloride (MAMPTAC™), N,N,N-trimethyl-3-[( ... [Propanyl)amino]propanediamine chloride (APTAC™), diallyl dimethylammonium chloride (DADMAC™), or N,N,N-trimethyl-2-[(2-methyl-1-oxo-2-propenyl)]ethylammonium (MADQUAT™); N,N,N-trimethyl-3-[(2-methyl-1-oxo-2-propenyl)amino]propanediamine chloride, N,N,N-trimethyl-3-[(1-oxo-2-propenyl)amino] Propranolium chloride, diallyl dimethyl ammonium chloride, or N,N,N-trimethyl-2-[(2-methyl-1-oxo-2-propenyl)]ethylammonium with acrylamide, methacrylamide, vinylpyrrolidone, (2-hydroxyethyl) acrylate, (2-hydroxyethyl) methacrylate, (2,3-dihydroxypropyl) acrylate, (2,3-dihydroxypropyl) methacrylate, hydroxyethylacrylamide, N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N,N-diethylacrylamide, N,N- Branched or crosslinked copolymers of diethylmethylacrylamide, N-methylacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-(tert-butyl)acrylamide, N-methylmethylacrylamide, N-ethylmethylacrylamide, N-propylmethylacrylamide, N-isopropylmethylacrylamide, N-butylacrylamide, N-(tert-butyl)methylacrylamide, N,N-dipropylacrylamide or tris(hydroxymethyl)acrylamidomethylmethane (THAM); - Manufacturers of CARBOPOLTM, PEMULENTM, ARISTOFLEXTM, ARISTOFLEX TMAVC, ARISTOFLEX TMAVC, ARISTOFLEX TMHMB, SEPIMAXTM Zen, SEPIMAXTM C, SEPIGELTM 305, SEPIGELTM 501 SEPIGELTM 502 SIMULGELTM 600 SIMULGELTM EG SIMULGELTM EPG SIMULGELTM NS SIMULGELTM INS 100 SIMULGELTM FL SIMULGELTM SMS 88. SIMULGELTM800.SIMULGELTM A. SEPIPLUSTM 400. SEPIPLUSTM 250. SEPIPLUSTM S. SEPIPLUSTM NUDE. SEPILIFETM G305 ET 26, FlOCARETM ET30, FlOCARETM ET 58, FlOCARETM PSD 30, VISCOLAMTM AT 64, VISCOLAMTM AT 100P, VISCOLAMTM AT EF, NOVEMERTM EC-1, NOVEMERTM EC-2, COSMEDIATM SP, COSMEDIATM ACE, SEPINOVTM EMT 10, SEPINOVTM WEO and SEPINOVTM P88 are the best products. - Non-crosslinked polysaccharide thickeners or gelling agents, such as glucan or glucose homopolymer, glucomannoglucan, xyloglycan, galactomannan, wherein the degree of substitution (DS) of the D-galactose unit on the main D-mannose chain is between 0 and 1, more particularly between 1 and 0.25, such as those derived from cassia gum (DS = 1 / 5), locust bean gum (DS = 1 / 4), tara gum (DS = 1 / 3), guar gum (DS = 1 / 2), or fenugreek gum (DS = 1 / 2). 1) Galactomannan; sulfated galactan, especially carrageenan and agar, uronans, especially alginate, alginates and pectin, heteropolymers of monosaccharides and uronic acids, especially xanthan gum, gellan gum, gum arabic exudate and ebony gum exudate, glucosamine polysaccharides.

[0044] The solubilizer used in this invention is a chemical substance or composition capable of solubilizing hydrophobic substances (such as fragrances and flavorings) that are insoluble in water, an aqueous phase, a water-alcohol phase, or a water-diol phase. Examples of such agents optionally present in cosmetic or pharmaceutical topical formulations used as defined above or as the subject of the invention include: - Polysorbates, such as polysorbate 20, polysorbate 60 and polysorbate 80. - Alkyl polyglycoside compositions, wherein the linear or branched alkyl chain comprises 4 to 10 carbon atoms, such as n-butyl polyglucoside, n-butyl xyloside, n-pentyl polyglucoside, n-pentyl xyloside, n-hexyl polyglucoside, n-hexyl xyloside, n-heptyl polyglucoside, n-heptyl xyloside, n-octyl polyglucoside, n-octyl xyloside, n-nonyl polyglucoside, n-nonyl xyloside, n-decyl polyglucoside, n-decyl xyloside; - Formula R10-(OE) n’-H ethoxylated fatty alcohols, wherein R10 represents a linear or branched, saturated or unsaturated aliphatic group containing 12 to 22 carbon atoms, preferably 12 to 18 carbon atoms, more particularly 12 to 16 carbon atoms, and n' represents an integer greater than or equal to 5 and less than or equal to 200, more particularly greater than or equal to 5 and less than or equal to 100, more particularly greater than or equal to 10 and less than or equal to 100; for example, formula R10-(OE). n’ -H compounds, where R10 represents dodecyl and n' represents an integer greater than or equal to 7 and less than or equal to 25; - Equation R20-C(=O)-(OE) m' The polyethoxylated fatty acid, wherein R20 represents a linear or branched, saturated or unsaturated aliphatic group containing 12 to 22 carbon atoms, more particularly 12 to 18 carbon atoms, and m' represents an integer greater than or equal to 10 and less than or equal to 100, more particularly greater than or equal to 15 and less than or equal to 100, and even more particularly greater than or equal to 15 and less than or equal to 50; - Hydrogenated and ethoxylated oils, especially those containing at least one triglyceride or one diglyceride or one monoglyceride, such as hydrogenated and ethoxylated castor oil sold under the name PEG-40 hydrogenated castor oil containing 40 moles of ethylene oxide. Examples of emulsifiers optionally present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above include those selected from alkyl polyglycoside compositions, particularly alkyl polyglucosides and alkyl xylosides, alkyl polyglycoside and fatty alcohol compositions, polyglycerol esters, particularly decaglycerol oleate, decaglycerol isostearate, decaglycerol monolaurate, decaglycerol monolinoleate, decaglycerol monomyristate, alkoxylated polyglycerol esters, polyglycol polyhydroxystearates, polyglycerol polyhydroxystearates, and alkoxylated polyglycerol polyhydroxystearates.

[0045] Examples of oils optionally present in cosmetic or pharmaceutical topical formulations that are the subject of the use or invention as defined above include: - Linear alkanes containing 11 to 19 carbon atoms, such as undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, and nonadecane; - Branched alkanes containing 7 to 40 carbon atoms, such as isododecane, isopentadecane, isohexadecane, isohexadecane, isohexadecane, isohexadecane, isohexadecane, or isoeicosane, or mixtures thereof, as mentioned below and identified by their INCI names: C 7-8 Isoalkanes (C 7-8 isoparaffin), C 8-9 Isoalkanes, C 9-11 Isoalkanes, C 9-12 Isoalkanes, C 9-13 Isoalkanes, C 9-14 Isoalkanes, C 9-16 Isoalkanes, C 10-11 Isoalkanes, C 10-12 Isoalkanes, C 10-13 Isoalkanes, C 11-12 Isoalkanes, C 11-13 Isoalkanes, C 11-14 Isoalkanes, C 12-14 Isoalkanes, C 12-20 Isoalkanes, C 13-14 Isoalkanes, C 13-16 Isoalkanes; - cycloalkanes optionally substituted with one or more linear or branched alkyl groups; - White mineral oils, such as those sold under the following names: MARCOL™ 52, MARCOL™ 82, DRAKEOL™ 6VR, EOLANE™ 130, and EOLANE™ 150; - Hemisqualane (or 2,6,10-trimethyldodecane; CAS No.: 3891-98-3), squalane (or 2,6,10,15,19,23-hexamethyltetracosane), hydrogenated polyisobutylene or hydrogenated polydecene; - A mixture containing 15 to 19 carbon atoms of alkanes, said alkanes being linear alkanes, branched alkanes, and cycloalkanes, and more particularly a mixture (M1) comprising, by mass, greater than or equal to 90% and less than or equal to 100% by mass of branched alkanes; greater than or equal to 0% and less than or equal to 9%, more particularly less than 5% by mass of linear alkanes; and greater than or equal to 0% and less than or equal to 1% by mass of cycloalkanes, such as mixtures sold under the names EMOGREEN™ L15 or EMOGREEN™ L19; - Fatty alcohol ethers of the formula Z1-O-Z2, wherein Z1 and Z2, whether the same or different, represent linear or branched alkyl groups containing 5 to 18 carbon atoms, such as dioctyl ether, didecyl ether, bis(dodecyl) ether, dodecyl octyl ether, bis(hexadecyl) ether, (1,3-dimethylbutyl)tetradecyl ether, (1,3-dimethylbutyl)hexadecyl ether, bis(1,3-dimethylbutyl) ether or dihexyl ether; - Monoesters of fatty acids and alcohols of the formula R'1-(C=O)-O-R'2, wherein R'1-(C=O) represents a linear or branched, saturated or unsaturated acyl group containing 8 to 24 carbon atoms, and R'2, independent of R'1, represents a linear or branched, saturated or unsaturated hydrocarbon chain containing 1 to 24 carbon atoms, such as methyl laurate, ethyl laurate, propyl laurate, isopropyl laurate, butyl laurate, 2-butyl laurate, hexyl laurate, methyl cocoate, ethyl cocoate, propyl cocoate, isopropyl cocoate, butyl cocoate, 2-butyl cocoate, hexyl cocoate, methyl myristate, ethyl myristate, propyl myristate, isopropyl myristate, myristic acid Butyl palmitate, 2-butyl myristate, hexyl myristate, octyl myristate, methyl palmitate, ethyl palmitate, propyl palmitate, isopropyl palmitate, butyl palmitate, 2-butyl palmitate, hexyl palmitate, octyl palmitate, methyl oleate, ethyl oleate, propyl oleate, isopropyl oleate, butyl oleate, 2-butyl oleate, hexyl oleate, octyl oleate, methyl stearate, ethyl stearate, propyl stearate, isopropyl stearate, butyl stearate, 2-butyl stearate, hexyl stearate, octyl stearate, methyl isostearate, ethyl isostearate, propyl isostearate, isopropyl isostearate, butyl isostearate, 2-butyl isostearate, hexyl isostearate or isostearate; - Diesters of fatty acids and glycerol of the formula R'3-(C=O)-O-CH2-CH(OH)-CH2-O-(C=O)-R'4 and R'5-(C=O)-O-CH2-CH(O-(C=O)-R'6)-CH2-OH, wherein R'3-(C=O), R'4-(C=O), R'5-(C=O) and R'6-(C=O), whether the same or different, represent linear or branched, saturated or unsaturated acyl groups containing 8 to 24 carbon atoms; - Triesters of fatty acids and glycerol of the formula R'7-(C=O)-O-CH2-CH(O-(C=O)-R''8)-CH2-O-(C=O)-R''9, wherein R'7-(C=O), R'8-(C=O) and R'9-(C=O), whether the same or different, represent linear or branched, saturated or unsaturated acyl groups containing 8 to 24 carbon atoms; - Vegetable oils, such as phytosqualane or sweet almond oil, coconut oil, castor oil, jojoba oil, olive oil, rapeseed oil, groundnut oil, sunflower oil, wheat germ oil, corn germ oil, soybean oil, cottonseed oil, alfalfa oil, poppy seed oil, pumpkin seed oil, evening primrose oil, millet oil, barley oil, rye oil, safflower oil, candlenut oil, passionflower oil, hazelnut oil, palm oil, and apricot kernel oil. oil), calophyllum oil, sisymbrium oil, avocado oil, calendula oil, or oil derived from flowers or vegetables; -Ethoxylated vegetable oil.

[0046] In this invention, the term "wax" refers to a water-insoluble compound or mixture of compounds that has a solid appearance at a temperature greater than or equal to 45°C. Examples of waxes that may be present in cosmetic or pharmaceutical topical formulations used as defined above or as the subject of the invention include beeswax, carnauba wax, candelilla wax, ouricury wax, Japan wax, cork fibre wax, sugarcane wax, paraffin wax, lignitewax, lanolin wax, ozokerite wax, polyethylene wax, or silicone wax; plant waxes or microcrystalline waxes; and fatty alcohols, fatty acids, and glycerides that are solid at room temperature, such as shea butter or cocoa butter.

[0047] Examples of natural spring water or mineral water that may exist in topical cosmetic or pharmaceutical formulations for the purposes or subjects of the invention as defined above include Avène water, Vittel water, Uriage water, La Roche Posay water, La Bourboule water, Enghien-les-bains water, Saint-Gervais-les-bains water, Néris-les-bains water, Allevard-les-bains water, Digne water, Maiziers water, Neyrac-les-bains water, Lons leSaunier water, Rochefort water, Saint Christau water, Fumades water, Tercis-les-Bains water, Bagnères-de-Bigorres water, Eugénie-les-Bains water, Challes-les-Eaux water, Volvic water, Vals water, Vernière water, and Aix les Bains water, Alet water, Abatilles water, Arcens water, Arvie water, Asperjoc water, Badoit water, Cilas water, Contrexéville water, Evian water, Hépar water, Jouvence water, Mont-Roucous water, Ogeu water, Orezza water, Parot water, Perrier water, Plantcoët water, Quézac water, Rozana water, Saint-Alban-Les-Eaux water, Saint-Amand-les Eaux water, Saint-Georges water, Saint-Géron water, Saintte-Marguerite water, Saint-Yorre water, Salvetat water, Teissières-lès-Bouliès water, Thonon water, Treignac water, Courmayeur water, San Benedetto water, San Pellegrino water, or Vichy basin water.

[0048] Examples of deodorant agents that may exist in topical cosmetic or pharmaceutical preparations for the purposes or subjects of the invention as defined above include alkali metal silicates, zinc salts such as zinc sulfate, zinc gluconate, zinc chloride, or zinc lactate; quaternary ammonium salts such as cetyltrimethylammonium salts or cetylpyridinium salts; glycerol derivatives such as glyceryl caprate, glyceryl caprylate, and polyglyceryl caprate; capryloylglycine; 1,2-decanediol; 1,3-propanediol; salicylic acid; and sodium bicarbonate. Bicarbonate; cyclodextrins; metallic zeolites; Triclosan™; aluminum salts, such as aluminum bromohydrates, aluminum chlorohydrates, aluminum chloride, aluminum sulfate, or aluminum lactate; mixed aluminum zirconium chlorohydrates, such as aluminum zirconium chlorohydrates, aluminum zirconium trichlorohydrate, aluminum zirconium tetrachlorohydrate, aluminum zirconium pentachlorohydrate, or aluminum zirconium octachlorohydrate; sodium aluminum lactate;Complexes of aluminum chlorohydrates and glycols, such as aluminum chlorohydrate-glycol complex, aluminum chlorohydrate-propylene glycol complex, aluminum dichlorohydrate-propylene glycol complex, aluminum sesquichlorohydrate-propylene glycol complex, aluminum chlorohydrate-polyethylene glycol complex, aluminum dichlorohydrate-polyethylene glycol complex, and aluminum sesquichlorohydrate-polyethylene glycol complex.

[0049] As a hydrotropic agent that may be present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above, references may be made to xylene sulfonates, cumene sulfonates, hexylpolyglucoside, 2-ethylhexylpolyglucoside, or n-heptylpolyglucoside.

[0050] As antioxidants that can be present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above, references may be made to EDTA (ethylenediaminetetraacetic acid) and its salts, citric acid, tartaric acid, oxalic acid, BHA (butylated hydroxyanisole), BHT (butylated hydroxytoluene), and tocopherol derivatives such as tocopheryl acetate, dissolvine. TM GL 47S or CONTACTICEL TM .

[0051] As a sunscreen that may exist in cosmetic or pharmaceutical topical formulations for the purposes or inventions defined above, reference may be made to all those listed in Annex VII of the revised cosmetics directive 76 / 768 / EEC.

[0052] As an example of a solubilizer for organic sunscreens that may be present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above, LANOL can be mentioned. TM 37T, DUB TM 810PGM, DUB TM DIS, DUB TM DIPA, DUB TM DNPG or DUB TM SYNERSOL.

[0053] Examples of mineral sunscreens that may exist in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above include titanium oxides, zinc oxides, cerium oxides, zirconium oxides, yellow, red, or black iron oxides or chromium oxides.

[0054] Examples of solvents and co-solvents that may exist in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above include glycerol, diglycerol, glycerol oligomers, ethylene glycol, propylene glycol, butylene glycol, hexanediol, diethylene glycol, xylitol, erythritol, sorbitol, water-soluble alcohols such as ethanol, isopropanol or butanol, mixtures of water and said organic solvents, propylene carbonate, ethyl acetate, benzyl alcohol, and dimethyl sulfoxide (DMSO).

[0055] Examples of skin penetration enhancers that may exist in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above include glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether and diethylene glycol mono(n-butyl) ether, diethylene glycol monoethyl ether (or Transcutol-P), fatty acids such as oleic acid, fatty acid esters of glycerol such as behenoyl glyceride, palmitoyl stearate, behenoyl macroglycerides, polyoxyethylene (2) stearate ether, polyoxyethylene (2) oil ether, terpenes such as D-limonene, and essential oils such as eucalyptus oil.

[0056] Examples of stabilizers that may be present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above include microcrystalline waxes, more particularly ozokerites, mineral salts such as sodium chloride or magnesium chloride, and organosilicon polymers such as polysiloxane polyalkyl polyether copolymers.

[0057] Examples of active ingredients that may be present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above include: - Vitamins and their derivatives, especially their esters, such as retinol (vitamin A) and its esters (e.g., retinyl palmitate), ascorbic acid (vitamin C) and its esters, sugar derivatives of ascorbic acid (e.g., ascorbate glucoside), tocopherol (vitamin E) and its esters (e.g., tocopheryl acetate), vitamin B3 or B10 (nicotinamide and its derivatives). - Compounds with skin brightening or depigmenting effects, such as ω-undecelynoyl phenylalanine, glycerol monoesters and / or diesters of ω-undecelynoyl phenylalanine, ω-undecelynoyl dipeptide, arbutin, kojic acid, and hydroquinone, sold under the names Sepiwhite™ MSH and Sepicalm™ VG. - Compounds with soothing effects, such as Sepicalm™ S, allantoin, and bisabolol; - Analgesics or anti-inflammatory agents, such as acetaminophen, aspirin, salicylic acid, methyl, choline or glycol salicylate esters, 1-menthol, camphor, mefenamic acid, 1'-fluphenamic acid, indomethacin, and protizidic acid. acid), fentiazac, tolmetin, phenylbutazone, oxyphenbutazone, clofezone, pentazocine, mepirizole, hydrocortisone, cortisone, dexamethasone, fluocinolone, triamcinolone, medrysone, prednisolone, flurandrenolide, prednisone, halcinonide, methylprednisolone, fludrocortisone, corticosterone, paramethasone, betamethasone; (hetero)arylacetic acid 2-(hetero)aryl propionic acid, such as diclofenac, tiaprofenic acid, alminoprofen, etodolac, flurbiprofen, ibuprofen, ketoprofen, or naproxen. - Antiseptic agents, such as cetrimide, povidone-iodine, chlorhexidine, viodine, benzalkonium chloride, benzoic acid, nitrofurazone, benzoylperoxide, hydrogen peroxide, hexachlorophene, phenol, resorcinol, or cetylpyridinium chloride.

[0058] - Insecticides, such as trichlorfon, triflumuron, fenthion, bendiocarb, cyromazine, diflubenzuron, dicyclanil, fluazuron, amitraz, deltamethrin, cypermethrin, chlorfenvinphos, flumethrin, ivermectin, and abamectin. Abamectin, avermectin, doramectin, moxidectin, zeta-cypermethrin, diazinon, spinosad, imidacloprid, nitenpyram, pyriproxyfen, fipronil, cythioate, lufenuron, selamectin, and milbemycin oxime, chlorpyrifos, coumaphos, propetamphos, alpha-cypermethrin, high cis-cypermethrin, ivermectin, diflubenzuron, cyclodiene, carbamate, or benzoylurea; - Antimicrobial agents, such as sulfonamides, neomycin, tobramycin, gentamicin, amikacin, kanamycin, spectinomycin, paromomycin, netilmicin, polypeptides, cephalosporins, or oxazolidinones, such as ciprofloxacin, levofloxacin, or ofloxacin; - Compounds with moisturizing properties, such as urea, hydroxyurea, glycerol, polyglycerols, glyceryl glucoside, diglyceryl glucoside, polyglyceryl glucosides, or xylityl glucoside. - Plant extracts rich in polyphenols, such as grape extracts, pine extracts, wine extracts, and olive extracts. - Compounds with slimming or fat-decomposing effects, such as caffeine or its derivatives, Adiposlim™, Adipoless™, and fucoxanthin. - N-acyl proteins, N-acylated peptides such as Matrixil™, N-acyl amino acids, partially hydrolyzed products of N-acyl proteins, amino acids, peptides, and complete protein hydrolysates. - Plant extracts, such as soybean extracts (e.g., Raffermine™), wheat extracts (e.g., Tensine™ or Gliadine™), plant extracts such as tannin-rich plant extracts, isoflavone-rich plant extracts, or terpene-rich plant extracts; freshwater or saltwater algae extracts; marine plant extracts; marine extracts in general, such as coral. - Essential waxes; - Bacterial extract; - Ceramides; - Phospholipids; - Compounds with antimicrobial or purifying effects, such as Lipacide™ C8G, Lipacide™ UG, Sepicontrol™ A5; Octopirox™ or Sensiva™ SC50; - Compounds with stimulating or excitatory properties, such as Physiogenyl™. - Panthenol and its derivatives, such as Sepip™ MP; - Anti-aging active agents, such as Sepilift™ DPHP, Lipacide™ PVB, Sepivinol™, Sepivital™, Manoliva™, Phyto-Age™, Timecode™ or Survicode™; - Anti-photoaging active agents; agents that protect the integrity of the dermal-epidermal boundary; agents that increase the synthesis of extracellular matrix components such as collagen, elastins, or glycosaminoglycans. - Active agents that act advantageously on chemical cell communication, such as cytokines, or active agents that act advantageously on physical cell communication, such as integrins. - Active agents that produce a "warming" sensation on the skin, such as skin microcirculation activators (e.g., niacin derivatives), or products that produce a "cooling" sensation on the skin (e.g., menthol and its derivatives). - Active agents that improve skin microcirculation, such as venotonic agents. - Draining active agents; decongesting active agents, such as extracts of Ginkgo biloba, ivy, common horse chestnut, bamboo, ruscus, butcher's broom, centella asiatica, fucus, rosemary, or willow. - Agents designed to treat hair or body hair, such as agents that protect melanocytes of the hair follicle, mimics of DOPAchrome tautomerase activity, synthetic SOD mimics such as manganese complexes, antioxidant compounds such as cyclodextrin derivatives, silica compounds derived from ascorbic acid, lysine pyrrolidone carboxylates or arginine pyrrolidone carboxylates, and combinations of cinnamic acid monoesters and diesters with vitamin C; - Skin tanning or bronzing agents, such as dihydroxyacetone (DHA), erythrulose, mesotartaric aldehyde, glutaraldehyde, glyceraldehyde, alloxan, ninhydrin, and plant extracts, such as redwoods from the genera *Pterocarpus* and *Baphia*, such as extracts of *Pterocarpus santalinus*, *Pterocarpus osun*, *Pterocarpus soyauxii*, *Pterocarpus erinaceus*, *Pterocarpus indicus*, or *Baphia nitida*. - Agents known for promoting or accelerating the tanning or bronzing of human skin, or for their skin-coloring effects, such as carotenoids (especially beta-carotene and gamma-carotene), sold under the trademarks "Carrot oil", SunTan Accelerator™, Zymo Tan Complex, MelanoBronze™, Monk's pepper extract, Unipertan VEG-24 / 242 / 2002, Try-Excell™, Actibronze™, Tyrostan™, Tyrosinol, InstaBronze™, Tyrosilane, Exymol, Bronzing SF Peptide powder, Melitane, Melatimes Solutions™, Tanositol™, Thalitan™, Phycosaccharide™ AG, Melactiva™, and Biotanning™.

[0059] - As aromatic or flavoring substances that may be present in topical cosmetic or pharmaceutical formulations for the purposes or subjects of the invention as defined above, references may be made to those extracted from flowers, such as rose, jasmine, tuberose, champak, mimosa, carnation, osmanthus, narcissus, lavender, gardenia, frangipani flowers, ylang-ylang flowers, lotus flowers, acacia flowers, sweet orange blossom, bitter orange blossom, or neroli blossom; those extracted from leaves, moss, bark, resin, or buds (such as blackcurrant buds); oakmoss, beech moss. moss or lichen; acacia leaves, basil leaves, valerian leaves, gentian leaves, violet leaves, geranium leaves, labdanum leaves, rosemary leaves, patchouli leaves, or verbena leaves; cinnamon bark, ash bark, cassia bark, cascarilla bark; sandalwood, cedarwood, rosewood, agarwood, birchwood, guaiac wood;Peru balsam, Tolu balsam, benzoin resin, myrrh, labdanum resin, elemiresin, olibanum, opoponax, guggul, and those extracted from the needles and branches of pine, spruce, or fir; those extracted from tarragon, lemongrass, sage, or thyme; and those extracted from pods, beans, or berries, such as tonka bean, vanilla pods, cardamom, coriander, and star anise. Anise, bitter almond, cumin, cloves, juniper berries; or those extracted from citrus fruits, such as lemon, orange (including limetta and bergamot), mandarin; and those extracted from roots, such as angelica, celery, cardamom, iris, sweet flag, cactus, or vetiver roots.

[0060] As aromatic or flavoring substances that may be present in topical cosmetic or pharmaceutical formulations for the purposes or subjects of the invention as defined above, references may also be made to those derived from: yarrow, calamus, garlic, ajowan, amyris, dill, anise, angelica, tea tree, basil, Bay Saint Thomas, benzoin, bergamot, guaiac wood, camphor wood, rosewood, sandalwood, siam wood, black birch, chamomile, camphor tree, cinnamon, cardamom, carrot, caraway, cedar, celery, and sea fennel. fennel, cistus, lemon, citronella, clementine, kaffir lime oil, copaiba, coriander, cryptomeria, cumin, turmeric, cypress, frankincense, spruce oil, tarragon, fennel, fragonia, galbanum, wintergreen, juniper, geranium, ginger, clove or clove leafLeaf, Helichrysum, Hyssop, Iary, Inula, Katrafay, Khella, Kunzea, Lavender, Lavandin, Mandarin, Niaulouli, Peppermint, Orange, Grapefruit, Rosemary, Thyme, Ylang-ylang, Ravintsara, Sage, Cabreuva, Lemongrass, Palmarosa, St. John's wort wort, jasmine, chamomile, melissa, pine, ginger, parsley, artemisia, hemp, hop, or wild thyme.

[0061] As aromatic or flavoring substances that may be present in cosmetic or pharmaceutical topical formulations for the purposes or subjects of the invention as defined above, references may also be made to musk, castoreum, civet, ambergris, beeswax absolute, or hyraceum.

[0062] Chemical compounds that can be present in cosmetic or pharmaceutical topical formulations as synthetic aromatic or flavoring substances, as defined above as the subject of the invention, may be mentioned as follows: - Terpenes (monoterpenes and sesquiterpenes), such as α-myrcene or β-myrcene, limonene, α-pinene or β-pinene, camphene, cadinene, cedrene, farnesene, caryophyllene, chamazulene, 1,1-dimethoxy-2,2,5-trimethyl-4-hexene, curcumene, crithmene, hisamahalenes, limonene, para-cymene, rose ether (oxide) or tetrarlabdane oxide; terpinenes, terpinolenes or vetivenes; - Esters, such as benzyl acetate, bornyl acetate, citronellylacetate, cedryl acetate, dihydromyrcenylacetate, dimethylbenzylcarbinyl acetate, ethyl acetate, farnesyl acetate, fenchyl acetate, hexyl acetate, geranyl acetate, isobutyl acetate, isononyl acetate, isoamyl acetate, isobornylacetate, isopulegyl acetate, linalyl acetate, menthyl acetate, methyl phenyl carbinyl acetate, neryl acetate, nonyl acetate, 2-tert-butylcyclohexyl acetate, phenethyl acetate, 4-tert-butylcyclohexyl acetate, and prenyl acetate. Acetate), styrallyl acetate, terpenyl acetate, or vetiveryl acetate; methyl anthranilate, benzyl benzoate, isobutyl benzoate, linalyl benzoate, coumarin, ethyl butanoate, benzyl butanoate, isoamyl butanoate, benzyl butyrate, ethyl butyrate, isoamyl butyrate, or linalyl butyrate; butyl cinnamate, allyl cinnamate, or ethyl cinnamate; benzyl formate, citronellyl formate. methyl formate, hedioneformate, geranyl formate, or methyl formate.Ethyl methylphenylglycinate, allyl amyl glycolate, allyl heptanoate, phenoxyethyl isobutyrate, cis-3-hexenyl isobutyrate, isoamyl methacrylate, ethyl naphtholate, hexyl neopentanoate, amyl propionate, alkylcyclohexyl propionate, allylcyclohexane propionate, linalyl propionate, styrallyl propionate, or citronellyl propionate; methylsalicylate, benzyl salicylate. salicylate or ethyl salicylate or hexyl tiglate; - Alcohols and phenols, such as benzyl alcohol, alpha-terpineol, anethole, carotol, chavicol, estragole, cineole, cinnamyl alcohol, citronellol, p-cresol, cumyl alcohol, 3,7-dimethyl-1-octanol, dimethyl benzyl carbinol, fenchyl alcohol, eucalyptol, farnesol, eugenol, and isononyl alcohol. alcohol, isoeugenol, guaiacol, geraniol, globulol, linalool, menthol, dihydromyrcenol, nerolidol, nerol, phenylethyl alcohol, safrole, isosafrole, phytol, isophytol, terpineol, tetrahydrolinalool, tetrahydromyrcenol, thymol, vetiverol, undecavertol; - Aldehydes, such as phenylacetaldehyde, salicylaldehyde, anisaldehyde, caprylaldehyde, cinnamaldehyde, hexylcinnamaldehyde; bourgeonal, citral, citronellal, hydroxycitronellal, citronellyloxyacetaldehyde, cyclamenaldehyde. Aldehydes, cuminaldehyde, cyclal, 2,4-dimethyl-3-cyclohexene-1-carboxaldehyde, dodecanal, ethanal, octanal, decanal, geranials, helional, lactones such as gamma-undecalactones, lilial, methyl-n-nonylacetaldehyde, methyl octylacetaldehyde, undecanal, or vanillin; - Ketones, such as benzylacetone, 7-methyl-2H-benzo-1,5-dioxepin-3(4H)-one, carvone, camphor, civetone, damascones, damascenones, ethylpentyl ketone, ethylhexyl ketone, geranylacetone, jasmone, irones, 3-hydroxy-2-methyl-4H-pyran-4-one, ethyl maltol, menthone, isomenthone, muscone, methylheptenone, and ionones such as methyl ionone. ionone), 4-methylacetophenone, methyl pentyl ketone, methyl heptyl ketone, methyl hexyl ketone, α-isomethyl ionone, or methylcedryl ketone; - Ethers, such as anethole, benzyl ethyl ether, cedryl methyl ether, and p-tolyl methyl ether; - Artificial musk derived from various nitro compounds, such as musk ambrettes, muskketones, xylenes, and macrocyclic musks; - Nitriles, such as trimethyl-3,5,7-octane(en)nitrile and its α-substituted derivatives, citronellylnitrile, citronitrile, and geranyl nitrile. Detailed Implementation

[0063] The following examples illustrate the present invention, but do not limit the invention.

[0064] Xanthan gum crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The synthesis method includes the following steps: Step A): Under mechanical stirring, load 193 g of a water-alcohol mixture of 95% ethanol and water (mass ratio 62 / 38) and 30 g of xanthan gum into a 1-liter glass-jacketed reactor. Step c): Adjust the pH of the mixture prepared in step A) to 12.5 using a tetramolar aqueous solution of sodium hydroxide at 25°C. Step d): Add 0.018 g STMP (i.e., 0.06% by mass based on xanthan gum) to the mixture from step c) heated to 50°C; stir at this temperature for 2 hours, then cool to 25°C. Step e): Adjust the pH of the reaction medium to 7 using a 5-molar concentration of pentamolar hydrochloric acid aqueous solution. Step f): Gravity filtration of the reaction medium on filter paper (average filtration of 4 µm to 7 µm). Step g): The product recovered in step f) was dried under vacuum in an oven at a constant temperature of 50°C for 16 to 20 hours; thereby obtaining 24 g of polysaccharide (P1) in the form of a white powder, with a yield of 80% (relative to the amount of xanthan gum introduced).

[0065] Xanthan gum crosslinked by STMP was prepared in a water-ethanol mixture (comparison). The same method as described above for preparation P1 was performed, but the pH of the mixture prepared in step A) was adjusted to 7.0 instead of 12.5. 24 g of polysaccharide (P1') was isolated as a white powder, with a yield of 80% (relative to the amount of xanthan gum introduced).

[0066] Xanthan gum crosslinked by STMP (according to the present invention) was prepared in a water-ethanol mixture. The synthesis method includes the following steps: Step A): Under mechanical stirring, load 200g of a water-alcohol mixture of 95% ethanol and water (mass ratio 75 / 25) and 60g of xanthan gum into a 1-liter glass-jacketed reactor. Step c): Adjust the pH of the mixture prepared in step A) to 12.0 at 20°C using a tetramolar aqueous solution of sodium hydroxide. Step d): Add 0.69 g STMP (i.e., 1.15% by mass based on xanthan gum) to the mixture from step c) heated to 35°C; stir at this temperature for 1 hour, then cool to 20°C. Step e): Adjust the pH of the reaction medium to 7 using a 5-molar concentration of pentamolar hydrochloric acid aqueous solution. Step f): Gravity filtration of the reaction medium on filter paper (average filtration of 4 to 7 µm). Step g): The product recovered in step f) is dried in an oven at 50°C under vacuum for 16 to 20 hours; thereby obtaining polysaccharide (P2) in the form of a white powder.

[0067] Lipophilized xanthan gum crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described above for preparing P1 was performed, but xanthan gum was replaced with chemically modified xanthan gum esterified with dodecanoate. 26 g of polysaccharide (P3) was isolated as a white powder, with a yield of 86.7% (relative to the introduced C-12 lipophilized xanthan gum).

[0068] Xanthan gum crosslinked by STMP was prepared in a water-isopropanol mixture (according to the present invention). The same method as described above for preparation P1 was performed, but isopropanol was used instead of ethanol. 24.5 g of polysaccharide (P4) was isolated as a white powder, with a yield of 81.7% (relative to the amount of xanthan gum introduced).

[0069] Konjac gum crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described in preparation P2 was performed, but xanthan gum was used instead of konjac gum. The polysaccharide was isolated as a white powder (P5).

[0070] Guar gum crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described in preparation P2 was performed, but guar gum was used instead of xanthan gum. 54.3 g of polysaccharide (P6) was isolated as a white powder, with a yield of 90.5% (relative to the amount of guar gum introduced).

[0071] Kappa-carrageenan (k-carrageenan) crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described in preparation P2 was performed, but k-carrageenan was used instead of xanthan gum, and the medium obtained in step A) was heated at 80°C for 1 hour. 52.5 g of the polysaccharide (P7) was isolated as a white powder, with a yield of 87.5% (relative to the amount of k-carrageenan introduced).

[0072] Iota-carrageenan (i-carrageenan) crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described above in preparation P7 was performed, but i-carrageenan was used instead of κ-carrageenan. 52.8 g of the polysaccharide was isolated as a white powder (P8), with a yield of 88% (relative to the amount of i-carrageenan introduced).

[0073] i-Carrageenan crosslinked by STMP was prepared in a water-ethanol mixture and in the presence of calcium sulfate (according to the present invention). The same method as described above for preparation P8 was performed, but 0.3 g of calcium sulfate was introduced in step A). ​​The polysaccharide was isolated as a white powder (P9).

[0074] K-carrageenan crosslinked by STMP was prepared in a water-ethanol mixture and in the presence of calcium sulfate (according to the present invention). The same method as described above for preparation P9 was performed, but with K-carrageenan instead of I-carrageenan. 53.3 g of the polysaccharide (P10) was isolated as a white powder, with a yield of 88.8% (relative to the amount of K-carrageenan introduced).

[0075] A mixture of xanthan gum and i-carrageenan crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described above for preparation P8 was performed, but 54 g of xanthan gum (xanthan gum / i-carrageenan mass ratio = 9.0) was added in step A). ​​54.7 g of polysaccharide (P11) was isolated as a white powder, with a yield of 91.2% (relative to the introduced xanthan gum and i-carrageenan mixture).

[0076] A mixture of xanthan gum and i-carrageenan crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described in preparation P11 was performed, but the xanthan gum / i-carrageenan mass ratio was reversed. For this purpose, 6 g of xanthan gum and 54 g of i-carrageenan were used (xanthan gum / i-carrageenan mass ratio = 0.1). 54.4 g of polysaccharide (P12) was isolated as a white powder, with a yield of 90.7% (relative to the introduced xanthan gum and i-carrageenan mixture).

[0077] A mixture of xanthan gum and κ-carrageenan crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described in preparation P11 was performed, but κ-carrageenan was used instead of κ-carrageenan (xanthan gum / κ-carrageenan mass ratio = 9.0). 53.5 g of polysaccharide (P13) was isolated as a white powder, with a yield of 89.2% (relative to the introduced xanthan gum and κ-carrageenan mixture).

[0078] A mixture of xanthan gum and κ-carrageenan crosslinked by STMP was prepared in a water-ethanol mixture (according to the present invention). The same method as described in preparation P12 was performed, but the xanthan gum / κ-carrageenan mass ratio was reversed. For this purpose, 6 g of xanthan gum and 54 g of κ-carrageenan were used (xanthan gum / κ-carrageenan mass ratio = 0.1). 54.3 g of polysaccharide (P14) was isolated as a white powder, with a yield of 90.5% (relative to the introduced xanthan gum and κ-carrageenan mixture).

[0079] Preparation of Aqueous Gels - Evaluation of the Thickening Properties of the Prepared Polymers. The thickening properties of the polysaccharides (P1) to (P14) crosslinked by STMP according to the present invention were evaluated and compared with the thickening properties of the corresponding non-crosslinked polysaccharides. The same characterization was performed on the polysaccharides (P1'), whose crosslinking steps were carried out at low pH outside the scope of the present invention.

[0080] - Preparation of the aqueous gel: The method for producing the aqueous gel involves introducing the amount of water required to prepare 800 grams of gel into a 2-liter beaker, which is 792 grams of water in the case of a gel containing 1% by mass of the crosslinked product. A mechanical stirrer impeller connected to a motor is placed at the bottom of the beaker. Stirring is initiated, and the required amount of crosslinked polysaccharide is introduced into the beaker while stirring. Stirring creates eddies that disappear as the polysaccharide becomes hydrated and forms a gel. In certain cases where the polysaccharide develops its viscosity under thermal effects, it may be necessary to heat the gel to between 50°C and 100°C to aid dissolution. A portion of the formed gel is reserved for viscosity measurement. Another portion is used to prepare a gel containing 1% polysaccharide + 0.5% sodium chloride. For this purpose, 398 grams of gel is stirred using a mechanical stirrer impeller connected to a motor, and then 2 grams of sodium chloride is added. Stirring is maintained until complete dissolution and a homogeneous gel is obtained. The gel thus prepared is evaluated 3 hours after preparation, and then 24 hours later. The viscosity of the gel was measured using a Brookfield RVT viscometer (speed 5, with a rotor adapted to the viscosity) or a Brookfield LVT viscometer (speed 6). The results are summarized in Tables 1 and 3 below.

[0081] Table 1

[0082] Table 2

[0083] Table 3

[0084] nd: Not determined Increase in viscosity = [(Viscosity (PX) - Viscosity of the corresponding non-crosslinked polysaccharide) / Viscosity of the corresponding crosslinked polysaccharide] × 100. in conclusion - To demonstrate the successful operation of the cross-linking reaction, the cross-linked polysaccharide (~100% polymer) was then precipitated and separated into powder form.

[0085] - In most cases, cross-linking of polysaccharides via STMP can increase the viscosity of gels containing 1% or 2% cross-linked polysaccharides in the presence or absence of NaCl. These relative increases relative to the same uncross-linked polysaccharides vary between 3.3% (see (P6)) and 935% (see (P1)). Decreases are observed in limited quantities (see (P3), (P13), and (P14)).

[0086] - Using ethanol or isopropanol as a crosslinking cosolvent can achieve a considerable increase in gel viscosity (see (P1) and (P4)).

[0087] Examples (P1) and (P1') were able to assess the effect of pH (12.5 and 7.0, respectively) during the crosslinking step.

[0088] - The crosslinking method according to the invention has been verified on individual polysaccharides and mixtures of polysaccharides.

[0089] Examples of cosmetic topical formulations according to the present invention

[0090] Table 4

[0091] Table 5

[0092] Table 6

[0093] Table 7

[0094] Table 8

[0095] Table 9

[0096] Table 10

[0097] Table 11

[0098] Table 12

[0099] Table 13

[0100] Table 14

Claims

1. A method for preparing cross-linked polysaccharides, comprising the following steps: - Step a), preparing a water-polar solvent mixture, wherein the polar solvent is selected from aliphatic alcohols containing 1 to 4 carbon atoms, ketones containing 3 to 5 carbon atoms, and polyols containing 2 or 3 hydroxyl groups and 2 to 6 carbon atoms, wherein the preparation is carried out by mixing water and the polar solvent in a mass ratio of the polar solvent to water greater than or equal to 0.4 and less than or equal to 19.

0. - Step b), dispersing at least one polysaccharide in the water-polar solvent mixture prepared in step a) to obtain a reaction medium comprising, by weight, a polysaccharide mass percentage greater than 10% and less than or equal to 55%; wherein the at least one polysaccharide used in step b) is selected from xanthan gum, xanthan gum with hydrocarbon branches containing 2 to 22 carbon atoms, more particularly xanthan gum esterified with dodecanoate, guar gum and konjac gum, carrageenan, more particularly kappa-carrageenan and iota-carrageenan, and mixtures of two or more of the polysaccharides in the group thereof; - Step c), adjusting the pH of the reaction medium prepared in step b) to a value greater than or equal to 8.0 and less than or equal to 13.0 by adding alkali; - Step d), crosslinking the at least one polysaccharide by adding a phosphate crosslinking agent selected from sodium trimetaphosphate (STMP) and sodium tripolyphosphate (STPP) to the alkaline reaction medium obtained at the end of step c), to obtain an alkaline dispersion containing the crosslinked polysaccharide; - Step e), adjust the pH of the alkaline dispersion obtained at the end of step d) to a value less than or equal to 7.0 to obtain a non-alkaline dispersion of the at least one cross-linked polysaccharide; - Step f), filtering the non-alkaline dispersion obtained at the end of step e) to recover the at least one intended cross-linked polysaccharide therefrom, optionally followed by: - Step g), drying to remove trace amounts of residual solvent. - or step h), atomize the at least one cross-linked polysaccharide obtained in step f) to obtain a powder therefrom.

2. The method according to claim 1, wherein steps a) and b) are simultaneous and constitute a single step A), i.e., the reaction medium is prepared by mixing water, a polar solvent selected from aliphatic alcohols containing 1 to 4 carbon atoms, ketones containing 3 to 5 carbon atoms, and polyols containing 2 or 3 hydroxyl groups and 2 to 6 carbon atoms, and a polysaccharide, in proportions such that: - The mass percentage of the at least one polysaccharide is greater than 10% by mass and less than or equal to 55% by mass of the reaction medium, and - The mass ratio of the polar solvent to water in the mixture is greater than or equal to 0.4 and less than or equal to 19.

0.

3. The method according to any one of claims 1 to 2, wherein the polar solvent of the mixture prepared in step a) or the reaction medium prepared in step A) is selected from methanol, ethanol, butanol, isopropanol, acetone, methyl ethyl ketone, glycerol, 1,3-propanediol, butanediol, 1,3-butanediol, pentanediol, hexanediol and 2-methyl-2,4-pentanediol, and more particularly from ethanol and isopropanol.

4. The method according to any one of claims 1 to 3, wherein the mass ratio of the polar solvent to water in the mixture prepared in step a) or the reaction medium prepared in step A) is greater than or equal to 1.0 and less than or equal to 4.

0.

5. The method according to any one of claims 1 to 4, wherein the reaction medium prepared in step b) or step A) comprises, by weight, a mass percentage of the at least one polysaccharide greater than or equal to 15% and less than or equal to 45% of the polysaccharide, based on 100% of its mass.

6. The method according to any one of claims 1 to 5, wherein in step c), the pH is adjusted to a value greater than or equal to 10.0 and less than or equal to 12.

5.

7. The method according to any one of claims 1 to 6, wherein the mass ratio of the STMP or STPP crosslinking agent used in step d) to the at least one starting polysaccharide is greater than or equal to 0.0001 and less than or equal to 0.0700, more particularly greater than or equal to 0.0003 and less than or equal to 0.0300.

8. The method according to any one of claims 1 to 7, wherein the crosslinking agent used in step d) is sodium trimetaphosphate (STMP).

9. The use of cross-linked polysaccharides or mixtures of cross-linked polysaccharides obtained by the method according to any one of claims 1 to 8 for thickening, stabilizing or emulsifying cosmetic or pharmaceutical topical formulations or for suspending solid particles therein.

10. A topical formulation of cosmetics or pharmaceuticals, characterized in that... It comprises, by weight, 0.1% to 10.0%, more particularly 0.5% to 5.0% of cross-linked polysaccharides or mixtures of cross-linked polysaccharides obtained by the method according to any one of claims 1 to 8 as a thickener, stabilizer or emulsifier of the cosmetic or pharmaceutical topical formulation, or as a reagent capable of and intended to suspend solid particles within the cosmetic or pharmaceutical topical formulation.

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