Cosmetic powder for the prevention and / or treatment of perspiration and associated composition

Abstract

Powder for preventing and / or treating perspiration and composition comprising same The present invention relates to a cosmetic powder, in particular for preventing and / or treating perspiration, in which the particles comprise: - at least one alkali metal metasilicate and - at least one chelating compound chosen from the phosphonic derivatives of the following formula (I): (I) where R represents an alkyl radical, linear or branched, cyclic or non-cyclic, saturated or unsaturated, comprising from 1 to 10 carbon atoms, and n represents an integer between 1 and 10, and amino acids. It also relates to the method for manufacturing said powder and the composition comprising such a powder.

Description

Title of the invention: Cosmetic powder for preventing and / or treating perspiration and associated composition

[0001] The present invention relates to a cosmetic powder for preventing and / or treating perspiration. The present invention also relates to a method for manufacturing such a powder, as well as a cosmetic composition, in particular for preventing and / or treating perspiration, comprising such a powder.

[0002] The armpits, as well as certain other parts of the body, are generally the site of several discomforts which may come directly or indirectly from the phenomena of perspiration. These phenomena often lead to unpleasant and annoying sensations which are mainly due to the presence of sweat resulting from perspiration. In certain cases, perspiration makes the skin clammy and wets clothes, particularly in the armpits or back, thus leaving visible traces. Furthermore, the presence of sweat can cause the release of body odors which are most of the time unpleasant. Finally, during its evaporation, sweat can also leave salts and / or proteins on the surface of the skin which can cause whitish traces on clothes. Such discomforts must be taken into account even in the case of moderate perspiration.

[0003] In the cosmetic field, it is well known to use antiperspirant products containing substances which have the effect of limiting or even eliminating sweat flow in order to remedy the problems mentioned above. These products are generally available in the form of roll-ons, sticks, aerosols or sprays.

[0004] Antiperspirant substances are generally made up of aluminum and / or zirconium chlorohydrates. These substances reduce the flow of sweat by forming a plug in the sweat duct.

[0005] There is also a consumer demand for the use of compounds of natural origin.

[0006] Thus there is a need for compositions for preventing and / or treating perspiration which do not have all of the drawbacks described above, that is to say which do not involve the use of aluminum and / or zirconium chlorohydrates, while conferring a satisfactory antiperspirant effect.

[0007] Furthermore, the present invention also aims to provide a composition having the simplest possible formulation method and implementation method, in particular thanks to a form of antiperspirant active ingredient, not requiring special packaging, nor several compartments, but on the contrary a ready-to-use form, which can be incorporated into various galenics.

[0008] The inventors have now discovered that the use, on a keratin material, of a powder of particles comprising the association of an alkali metal metasilicate with at least one specific chelating compound chosen from phosphonic derivatives and amino acids, makes it possible to reduce the flow of sweat.

[0009] This biosilification technology is based according to the invention on the mixture present in the same particle of sodium metasilicate (MS) powder and phytic acid (PA). Its high potential for interaction with proteins, in particular sweat, proves to be a promising antiperspirant (AT) candidate.

[0010] This powder according to the invention does not require extemporaneous mixing, and therefore does not have the common drawbacks of certain extemporaneous technologies, linked to the high cost of two-compartment packaging or to difficulty of use by consumers.

[0011] The powder according to the invention also offers significant stability, whether in dispersion or in dilution in a liquid such as oil or water. For example, no gelling is observed. It can therefore advantageously be incorporated into various galenics, whatever their viscosity.

[0012] Surprisingly, the powder, even if not dispersed in the liquid phase, i.e. in the solid and dry state, has the capacity to react with sweat proteins and to penetrate the sweat canal to form a precipitate there.

[0013] Thus, the subject of the present invention is a cosmetic powder, in particular for preventing and / or treating perspiration, in which the particles comprise:

[0014] - at least one alkali metal metasilicate and

[0015] - at least one chelating compound chosen from phosphonic derivatives of formula (I) following:

[0016] [Chem.l] (I)

[0017] where R represents an alkyl radical, linear or branched, cyclic or non-cyclic, saturated or unsaturated, comprising from 1 to 10 carbon atoms, preferably from 4 to 8 carbon atoms, preferably between 5 and 7 carbon atoms, and n represents an integer between 1 and 10,

[0018] and amino acids;

[0019] characterized in that the weight ratio between said metasilicate and said chelating compound is in the range of 0.1 to 1; and

[0020] characterized in that it has a pH in aqueous dispersion in the range of 2 to 5; and

[0021] characterized in that it comprises particles in which said metasilicate and said chelating compound are present within the same particle.

[0022] and the particles have a volume median diameter in the range of 1 to 20 qm.

[0023] Preferably, said powder has an aqueous dispersion (1% of powder in water after 30 seconds of stirring) with a pH in the range of 2 to 5, preferably greater than 2 and less than 5.

[0024] The present invention also relates to a process for manufacturing the powder of the invention, characterized in that it comprises a step of atomization or lyophilization of an aqueous solution containing said metasilicate and said chelating compound, and the recovery of said powder thus formed.

[0025] The present invention also relates to a cosmetic composition, in particular for preventing and / or treating perspiration, comprising, in a cosmetically acceptable medium, at least one powder according to the invention.

[0026] By "cosmetically acceptable medium" is meant a medium compatible with the skin and / or its appendages or mucous membranes, which has a pleasant color, odor and feel and which does not generate discomfort (such as tightness) likely to discourage the consumer from using this composition.

[0027] Said cosmetically acceptable medium is also a medium which does not leave traces when applied, and thus does not stain clothing.

[0028] Said cosmetically acceptable medium preferably comprises an aqueous phase.

[0029] The composition according to the invention advantageously has a pH in the range from 2 to 5, preferably greater than or equal to 2 and less than 5. Preferably, the pH is in the range from 2 to 4, preferably from 2.5 to 3.5, preferably from 2.7 to 3.2, preferably from 2.7 to 2.9.

[0030] Finally, the present invention also relates to a cosmetic process for preventing and / or treating perspiration, characterized in that it comprises bringing a keratin material, preferably the skin, into contact with at least one powder as defined according to the invention, or with a composition according to the invention.

[0031] Preferably, the powder or composition according to the invention comprises at least one alkali metal metasilicate and at least two different chelating compounds chosen from phosphonic derivatives of formula (I) and amino acids.

[0032] Preferably, the powder or composition according to the invention comprises at least one alkali metal metasilicate and at least three different chelating compounds chosen from phosphonic derivatives of formula (I) and amino acids. Alkali metal metasilicate

[0033] The powder according to the invention comprises at least one alkali metal metasilicate.

[0034] The cosmetic process according to the invention comprises bringing a keratin material, preferably the skin, into contact with such a powder or a composition according to the invention comprising, in a cosmetically acceptable medium, said powder comprising at least one alkali metal metasilicate.

[0035] By "alkali metal metasilicate" is meant an anhydrous compound of formula M2 SiO3, but also the hydrated forms of general formula M2SiO3.nH2O, M being an alkali metal. Preferably, n varies from 1 to 10. Preferably, the alkali metal M is chosen from lithium (Li), sodium (Na) and potassium (K). Preferably, M represents sodium (Na). Advantageously, the alkali metal metasilicate is disodium metasilicate, preferably the anhydrous compound Na2SiO3.

[0036] As an example, we can cite the compound sold by the company Silmaco under the name “Sodium Metasilicate Anhydrous Granules or Powder”.

[0037] In particular, disodium metasilicate is different from sodium orthosilicate and sodium disilicate. Indeed, sodium orthosilicate is the compound of formula Na4SiO4, while sodium disilicate is the compound Na2Si2O5. Chelating compound

[0038] The powder according to the invention comprises at least one chelating compound, as defined below.

[0039] The cosmetic process according to the invention comprises bringing a keratin material, preferably the skin, into contact with a powder or a composition according to the invention, comprising, in a cosmetically acceptable medium, at least one chelating compound chosen from the phosphonic derivatives of the following formula (I):

[0040] [Chem.l] (I)

[0041] where R represents an alkyl radical, linear or branched, cyclic or non-cyclic, saturated or unsaturated, comprising from 1 to 10 carbon atoms, and n represents an integer between 1 and 10,

[0042] and amino acids.

[0043] The chelating compound may be chosen from the phosphonic derivatives of the following formula (I):

[0044] [Chem.l] R4O.P(QXPH^ (I)

[0045] where R represents an alkyl radical, linear or branched, cyclic or non-cyclic, saturated or unsaturated, comprising from 1 to 10 carbon atoms, and n represents an integer between 1 and 10.

[0046] By alkyl radical is meant a linear or branched, cyclic or non-cyclic, saturated or unsaturated hydrocarbon group, comprising from 1 to 10 carbon atoms, preferably from 4 to 8 carbon atoms, preferably from 5 to 7 carbon atoms.

[0047] Preferably, the alkyl radical is not substituted.

[0048] More preferably, the alkyl radical is linear saturated cyclic.

[0049] According to a particularly preferred form of the invention, the alkyl radical is the cyclohexyl radical.

[0050] Preferably, n is an integer between 4 and 8, preferably between 5 and 7. Preferably, n = 6.

[0051] Preferably, the phosphonic derivatives of formula (I) are such that R represents a saturated cyclic linear alkyl radical, comprising from 1 to 10 carbon atoms, preferably from 4 to 8 carbon atoms, preferably between 5 and 7 carbon atoms, and n represents an integer between 1 and 10, preferably between 4 and 8, preferably between 5 and 7 such as 6.

[0052] Preferably, the phosphonic derivative of formula (I) is phytic acid.

[0053] As an example, we can cite the compound sold by the company Tsuno Rice Fine Chemicals under the name “Phytic acid and water”.

[0054] The chelating compound can also be chosen from amino acids.

[0055] By “amino acid” is meant amino acids and their phosphorylated derivatives.

[0056] The amino acids may be of L or D configuration or their mixture, L configuration preference or DL ​​mix.

[0057] The amino acids are preferably chosen from alpha amino acids and more particularly from proteinogenic amino acids.

[0058] By “phosphorylated derivative” is meant an amino acid carrying an OH alcohol function whose hydrogen has been substituted by a phosphoryl function of formula PO3H2.

[0059] Preferably, the amino acid is chosen from serine, O-phosphoserine and histidine.

[0060] As an example, we can cite the compound sold by the company Merck under the name “DL-Serine”, or the compound sold by the company Merck under the name “L-Histidine” referenced H8000.

[0061] In a preferred embodiment of the invention, the chelating compound is chosen from phytic acid, serine, O-phosphoserine and histidine.

[0062] According to an advantageous embodiment, the powder according to the invention comprises at least one alkali metal metasilicate and at least two different chelating compounds.

[0063] According to yet another advantageous embodiment, the powder according to the invention comprises at least one alkali metal metasilicate and at least three different chelating compounds.

[0064] When the powder according to the invention comprises several different chelating agents, the mixture of chelating agents may designate a mixture of different phosphonic derivatives of formula (I), or a mixture of different amino acid derivatives, or a mixture of phosphonic derivative(s) of formula (I) and amino acid compound(s). Characterization of the powder according to the invention

[0065] Advantageously, the powder according to the invention is characterized by its particle size, and in that the particles preferably have a volume median diameter in the range of 1 to 20 qm, preferably 2 to 15 qm, measured in predispersion in a 1% SDS surfactant solution before introduction into the measuring cell of a liquid laser granulometer (for example, a Malvern Mastersizer 3000 type instrument). The size of the powder particles according to the invention can also be measured by SEM measurement (X2000 or X4000) on dry powder, as in the examples which follow.

[0066] Advantageously, the powder according to the invention comprises particles in which said metasilicate and said chelating compound are present within the same particle, preferably coexist within a particle, preferably exist separately, preferably without a covalent bond connecting them, within the same particle.

[0067] Advantageously, the powder according to the invention comprises, on the total weight of powder, at least 50%, preferably at least 60%, preferably at least 70%, preferably at least 80%, preferably at least 90%, preferably at least 95%, by weight, of particles in which said metasilicate and said chelating compound are present within the same particle.

[0068] Preferably, within the powder according to the invention, the weight ratio between said metasilicate and said chelating compound is in the range of 0.1 to 1, preferably 0.2 to 0.7, preferably 0.3 to 0.6, preferably 0.4 to 0.6, preferably 0.5.

[0069] Advantageously, the powder according to the invention, in particular when it is obtained by atomization, is characterized in that it comprises particles of spherical shape, at least partially dented.

[0070] Preferably, the powder according to the present invention has a pH in aqueous dispersion (powder at 1% by weight in water, after 30 seconds of stirring) in the range of 2 to 5, preferably 2 to 4, preferably 2.5 to 3.5, preferably 2.7 to 3.2, preferably 2.7 to 2.9.

[0071] Method for repairing a powder according to the invention

[0072] Advantageously, the process for preparing a powder according to the invention comprises a step of atomization or lyophilization of an aqueous solution containing said metasilicate and said chelating compound, and the recovery of the powder.

[0073] The powder according to the invention is advantageously manufactured from aqueous solutions of phytic acid and sodium metasilicate, homogenized to form a mother solution (MS).

[0074] Preferably, said aqueous solution, also called mother solution, has a total concentration of metasilicate(s) and chelating compound(s) of at least 1%, preferably in the range of 1 to 40%, preferably 1 to 30%, preferably 1 to 20%, by weight relative to the total weight of the composition.

[0075] Preferably, said aqueous solution has a pH in the range of 2 to 5, preferably 2 to 4, preferably 2.5 to 3.5, preferably 2.7 to 2.9.

[0076] Preferably, the weight ratio between said metasilicate(s) and said chelating compound(s) in said aqueous solution is in the range of 0.1 to 1, preferably 0.2 to 0.7, preferably 0.3 to 0.6, preferably 0.4 to 0.6, preferably 0.5.

[0077] This ratio ultimately allows the powder thus formed to present an acidic and optimal pH in aqueous dispersion:

[0078] - either when it is placed in aqueous dispersion in a composition according to the invention;

[0079] - either when the powder is in direct contact with sweat which itself contains water.

[0080] The mother solution manufactured above is transformed into powder, in particular by atomization, nebulization and / or spray drying, or it is freeze-dried, so that a powder or a friable dry material is recovered, which can also be homogenized or ground to obtain the desired powder particle size. Advantageously, the method of the invention further comprises a homogenization or grinding step after said atomization or freeze-drying step.

[0081] Atomization consists of dehydrating a nebulized liquid by a flow of hot air in order to obtain a powder: The mother solution is sprayed into fine droplets then the water is evaporated in an enclosure with a current of hot air (Spray drying). The powder obtained is carried by the air flow to a cyclone or a bag filter which separates the air from the powder. This step is for example carried out with an atomizer, such as those of the Buchi B290 brand.

[0082] Without wishing to be bound by theory, the inventors believe that it is this acid pH provided by the powder in aqueous dispersion, which promotes the biosilification reaction of the powder particles according to the invention with the sweat proteins, thus forming agglomerates which grow at the entrance or inside the sweat canal and allow to fix to the walls of the sweat canal (sufficiently so as not to be expelled too quickly by the flow of sweat: persistence of at least 8 hours) thus obtaining the effect of a remarkable antiperspirant.

[0083] Physicochemical characterizations were carried out on several different powders covering several pHs and concentrations of stock solutions, after analysis of these different batches by SEM on dry powder and morpho-granulometry after dispersion at 1% in water.

[0084] Depending on the mother solution used, in particular its pH and its concentration of metasilicate and chelating compound, the atomized powder forms are characterized by more or less spherical particles and populations of powders centered around a volume median diameter in the range of 2 pm to 10 pm.

[0085] The pH of the mother solution used for the manufacture of the powder has an influence on the antiperspirant efficacy of the powder: The pH of the mother solution is preferably in the range of 2 to 4, preferably 2.5 to 3.5, preferably 2.5 to 3.2, preferably 2.5 to 3, preferably 2.7 to 2.9.

[0086] In this widest pH range, at a fixed concentration, the lower the pH of the mother solution, the more acidic the powder obtained (pH measured in 1% aqueous dispersion of powder after 30 seconds of stirring), and the more it succeeds in creating a precipitate inside the sweat canal, at a greater depth. Also, the smaller the size of the powder particles, in particular by a weakly concentrated mother solution or an atomization process adjusted towards obtaining finer particle sizes, the more it succeeds in creating a precipitate inside the sweat canal, at a greater depth.

[0087] Furthermore, the more the dispersion or composition according to the invention is concentrated in active material, the lower the pH.

[0088] The smaller the grains, the greater the overall surface area of ​​powder in contact with water, the more effective the biosilification technology is because it diffuses against the flow of sweat to create a plug deeper in the sweat canal.

[0089] The parameters of the atomization of a powder influence the effectiveness. On the other hand, the lower the pH of the powder in dispersion, the better the measured antiperspirant effectiveness.

[0090] A significant loss of efficiency is measured for final pH values ​​greater than 5, or even greater than 4, or even greater than 3.5, in the case, for example, of powders prepared with mother solutions of concentrations greater than 10%.

[0091] An equivalent effectiveness was observed between a dispersion of these powders according to the invention and the application of pure powders. The dry forms (powder according to the invention) have the capacity to react with sweat proteins and to penetrate into the sweat canal like the compositions according to the invention, in particular the dispersions (for example aqueous), comprising this same powder according to the invention.

[0092] The present invention therefore also relates to a cosmetic composition, in particular for preventing and / or treating perspiration, comprising, in a cosmetically acceptable medium, at least one powder according to the invention.

[0093] Advantageously, the composition according to the invention has a pH in the range from 2 to 5, preferably greater than or equal to 2 and less than 5, preferably, said pH is in the range from 2 to 4, preferably from 2.5 to 3.5, preferably from 2.7 to 3.2, preferably from 2.7 to 2.9; with the same advantages as those previously explained on the effectiveness of biosilification in the presence of sweat proteins, and therefore on the antiperspirant effect. Cosmetically acceptable medium

[0094] The cosmetically acceptable medium may be aqueous.

[0095] The aqueous phase of the composition according to the invention preferably comprises water, and may further comprise other water-miscible solvents. Water-miscible solvents include short-chain monoalcohols, for example Cr-C4, such as ethanol or isopropanol; diols or polyols such as ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, 2-ethoxyethanol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether and sorbitol.

[0096] The composition according to the invention may also comprise at least one organic phase immiscible in water called fatty phase. This generally comprises one or more hydrophobic compounds which make said phase immiscible in water. Said phase may be liquid (in the absence of structuring agent) at room temperature (20-25°C). Preferably, the liquid organic phase immiscible in water in accordance with the invention generally comprises at least one oil, volatile or non-volatile, and optionally at least one structuring agent. By "oil" is meant a fatty substance which is liquid at room temperature (25°C) and atmospheric pressure (760 mm Hg or 105 Pa). The oil may be volatile or non-volatile.

[0097] The composition according to the invention may also comprise at least one solid fatty substance. Preferably, this solid fatty substance is chosen from waxes and pasty fatty substances and their mixtures.

[0098] Advantageously, the composition according to the invention further comprises at least one deodorant active ingredient.

[0099] In the context of the present invention, the term "deodorant active ingredient" means any active ingredient which, on its own, has the effect of masking, absorbing, improving and / or reducing the unpleasant odor resulting from the decomposition of human sweat.

[0100] As an illustration of these additional deodorant active ingredients, mention may in particular be made of bacteriostatic agents or bactericidal agents acting on the germs of axillary odors, such as 2,4,4'-trichloro-2'-hydroxydiphenyl ether (#Triclosan), 2,4-dichloro-2'-hydroxydiphenyl ether, 3',4',5'-trichlorosalicylanilide, 1-(3',4'-dichlorophenyl)-3-(4'-chlorophenyl)urea (#Triclocarban) or 3,7,11-trimethyldodeca-2,5,10-trienol (#Farnesol); quaternary ammonium salts such as cetyltrimethylammonium salts, cetylpyridinium salts; polyols such as glycerin, 1,3-propanediol (ZEMEA PROPANEDIOL® marketed by Dupont Tate and Lyle Bioproducts), 1,2-decanediol (Symclariol® from the company Symrise);Glycerin derivatives such as Caprylic / Capric Glycerides (CAPMUL MCM® from Abitec), Glycerol Caprylate or Caprate (DERMOSOFT GMCY® and DERMOSOFT GMC® respectively from STRAETMANS), Polyglyceryl-2 Caprate (DERMOSOFT DGMC® from STRAETMANS), biguanide derivatives such as polyhexamethylene biguanide salts; chlorhexidine and its salts; 4-Phenyl-4,4-dimethyl-2butanol (SYMDEO MPP® from Symrise); cyclodextrins; or alum.

[0101] The additional deodorant active ingredients may preferably be present in the composition according to the invention in weight concentrations ranging from 0.01 to 10% by weight relative to the total weight of the composition.

[0102] The composition according to the invention may also comprise at least one additional antiperspirant active agent. By "antiperspirant active agent" is meant any substance which, on its own, has the effect of reducing sweat flow, reducing the sensation of humidity on the skin linked to human sweat, or masking human sweat.

[0103] As an illustration of these additional antiperspirant active agents, mention may in particular be made of antiperspirant salts or complexes of aluminum and / or zirconium, preferably chosen from aluminum halohydrates; aluminum and zirconium halohydrates, zirconium hydroxychloride and aluminum hydroxychloride complexes with or without an amino acid such as those described in patent US-3792068.

[0104] Among the aluminum salts, mention may be made in particular of aluminum chlorohydrate in activated or non-activated form, aluminum chlorohydrex, the aluminum chlorohydrex polyethylene glycol complex, the aluminum chlorohydrex propylene glycol complex, aluminum dichlorohydrate, the aluminum dichlorohydrex polyethylene glycol complex, the aluminum dichlorohydrex propylene glycol complex, aluminum sesquichlorohydrate, the aluminum sesquichlorohydrex complex polyethylene glycol, aluminum sesquichlorohydrex propylene glycol complex, aluminum sulfate buffered by sodium aluminum lactate.

[0105] Among the aluminum and zirconium salts, mention may be made in particular of aluminum zirconium octachlorohydrate, aluminum zirconium pentachlorohydrate, aluminum zirconium tetrachlorohydrate, aluminum zirconium trichlorohydrate.

[0106] Complexes of zirconium hydroxychloride and aluminum hydroxychloride with an amino acid are generally known as ZAG (when the amino acid is glycine). Among these products are the aluminum zirconium octachlorohydrex glycine, aluminum zirconium pentachlorohydrex glycine, aluminum zirconium tetrachlorohydrex glycine and aluminum zirconium trichlorohydrex glycine complexes.

[0107] Aluminum sesquichlorohydrate is notably sold under the trade name REACH 301® by the company SUMMITREHEIS.

[0108] Among the aluminum and zirconium salts, mention may be made of complexes of zirconium hydroxychloride and aluminum hydroxychloride with an amino acid such as glycine having the INCI name: ALUMINUM ZIRCONIUM TETRACHLOROHYDREX GLY, for example that marketed under the name REACH AZP-908-SUF® by the company SUMMITREHEIS.

[0109] More particularly, use will be made of aluminum chlorohydrate in activated or unactivated form marketed under the trade names LOCRON S FLA®, LOCRON P, LOCRON L.ZA by the company CLARIANT; under the trade names MICRODRY ALUMINUM CHLOROHYDRATE®, MICRO-DRY 323®, CHLORHYDROL 50, REACH 103, REACH 501 by the company SUMMITREHEIS; under the trade name WESTCHLOR 200® by the company WESTWOOD; under the trade name ALOXICOLL PF 40® by the company GUILINI CHEMIE; CLURON 50%(r) by the company INDUSTRIA QUIMICA DEL CENTRO; CLOROHIDROXIDO ALUMINIO SO A 50%® by the company FINQUIMICA.

[0110] Preferably, the composition according to the invention comprises less than 5% by weight of aluminum salts, preferably less than 3% by weight, preferably less than 1% by weight, preferably less than 0.5% by weight of aluminum salts, relative to the total weight of the composition. According to a particular form of the invention, the composition according to the invention is completely free of aluminum salt.

[0111] The composition according to the invention may further comprise cosmetic adjuvants chosen from opacifiers, stabilizers, preservatives, perfumes, sunscreens, cosmetic active ingredients, fillers, suspending agents, sequestering agents, coloring materials or any other ingredient usually used in cosmetics for this type of application. Of course, the person skilled in the art will take care to choose this or these possible complementary compounds in a manner such that the advantageous properties intrinsically attached to the composition according to the invention are not, or not substantially, altered by the addition(s) envisaged. Dosage forms

[0112] The composition according to the invention is advantageously presented in one of the following forms: compact powder, stick, soft-solid, gel, emulsion, aqueous or oily dispersion, lotion and therefore in multiple device possibilities: roll-on, aerosol or spray, or any other type of dispenser suitable for these forms of deodorant and antiperspirant products.

[0113] The composition according to the invention can be presented in all the galenic forms conventionally used for topical application and in particular in the form of aqueous gels, aqueous or hydroalcoholic solutions. By adding a fatty or oily phase, it can be presented in the form of dispersions of the lotion type, emulsions of liquid or semi-liquid consistency of the milk type, obtained by dispersion of a fatty phase in an aqueous phase (O / W) or vice versa (W / O), or suspensions or emulsions of soft, semi-solid (commonly called "soft-solid") or solid consistency of the cream or gel type, or even multiple emulsions (W / O / W or O / W / O), microemulsions, vesicular dispersions of ionic and / or non-ionic type, or wax / aqueous phase dispersions. The composition according to the invention is prepared according to the usual methods.

[0114] The compositions may in particular be packaged in pressurized form in an aerosol device or in a pump bottle; packaged in a device provided with an openwork wall, in particular a grid; packaged in a device provided with a ball applicator ("roll-on"); packaged in the form of sticks, in the form of loose or compacted powder. In this respect, they contain the ingredients generally used in this type of product and well known to those skilled in the art.

[0115] Advantageously, the composition according to the invention is in solid form, in particular in the form of a stick, or in the form of a loose powder or compact powder, with or without liquid binder and / or solid binder.

[0116] Preferably, the composition according to the invention is pressurized and packaged in an aerosol device, in particular comprising at least one propellant.

[0117] The propellant used is preferably chosen from dimethyl ether, volatile hydrocarbons such as propane, isopropane, n-butane, isobutane, n-pentane and isopentane and their mixtures, optionally with at least one chlorinated and / or fluorinated hydrocarbon; among the latter, mention may be made of the compounds sold by the company Dupont de Nemours under the names Freon# and Dymel#, and in particular monofluorotrichloromethane, difluorodichloromethane, tetrafluorodichloroethane and 1,1-difluoroethane sold in particular under the trade name DYMEL 152 A® by the company DUPONT.

[0118] Advantageously, the propellant is chosen from volatile hydrocarbons.

[0119] More preferably, the propellant is chosen from isopropane, n-butane, isobutane, pentane and isopentane and mixtures thereof.

[0120] Carbon dioxide, nitrous oxide, nitrogen or compressed air can also be used as propellant.

[0121] Preferably, the composition according to the invention comprises as propellant carbon dioxide, nitrous oxide, nitrogen or compressed air, preferably compressed air.

[0122] The weight ratio between the liquid phase and the propellant gas varies in a ratio of 5 / 95 to 50 / 50, preferably from 10 / 90 to 40 / 60, and more preferably from 15 / 85 to 30 / 70.

[0123] According to the invention, the concentration of propellant is in the range of 5 to 95% by weight relative to the total weight of pressurized composition and more preferably from 50 to 85% by weight relative to the total weight of the pressurized composition according to the invention.

[0124] The dispensing means, which forms part of the aerosol device, generally consists of a dispensing valve controlled by a dispensing head, itself comprising a nozzle through which the composition according to the invention is vaporized. The container containing the pressurized composition may be opaque or transparent. It may be made of glass, polymeric material or metal, optionally covered with a layer of protective varnish.

[0125] The expressions “between ... and ...” and “ranging from ... to ...” must be understood inclusively, unless otherwise specified.

[0126] Concrete, but in no way limiting, examples illustrating the invention will now be given. Examples Operating mode#:

[0127] The powders (M) were obtained respectively by atomization ((M1 to M5) or by lyophilization (M6 to M8) followed by grinding, from an aqueous solution containing phytic acid and sodium metasilicate at a concentration of minimum 1% (see table below)

[0128] Ingredients: • Sodium metasilicate sold under the name “sodium metasilicate anhydrous granules or powder” by the company “SILMACO” • Phytic acid sold under the name “#Phytic Acid and Water » (aqueous solution at a concentration of 50%) by the company «#TSUNO RICE FINE CHEMICALS#» • Sodium silicate under the name “sodium silicate solution” by the company “MERCK SIGMA ALDRICH”.

[0129] [Tables 1] Solution (S) Quantity of sodium metasilicate (g) Quantity of sodium silicate (g) Quantity of 50% phytic acid (g) Quantity of water (g) PH SI 1.67 3.33 495 2.8 S2 8.33 16.67 475 2.6 S3 16.67 33.33 450 2.5 S4 25 50 425 2.5 S5 166 666 600 2 S6 16.6 66.6 60 2 S7 1.667 3.333 45 1.7 S8 16.67 66.6 60 1.2

[0130] Example of preparation of a solution:

[0131] Solution (S5) is prepared by mixing 166 grams of sodium metasilicate and 666 grams of a 50% aqueous solution of phytic acid in 600 ml of water. This solution is mechanically stirred at room temperature until the sodium metasilicate is dissolved (pH of the solution: 2).

[0132] The powders (Ml to M4) are obtained by atomization of the solution (SI to S4) carried out on the Buchi Mini Spray Dryer B-290 device with the following parameters: - Inlet temperature 170°C - Outlet temperature: 98°C - Solution temperature: 25°C

[0133] Nozzle pressure: 4.1 PSI

[0134] The powder (M5) is obtained by atomization of the solution (S5) produced on the APV device at EXTRACTIS with the following parameters: - Inlet temperature 185°C - Outlet temperature: 82°C - Solution temperature: 25°C

[0135] Nozzle pressure: 3 Bars

[0136] The powder (M6-M8) is obtained by lyophilization (then grinding) of the solution (S6) produced on the Christ Alpha 2-4 LD device with the following parameters: - Freezing temperature: -20°C - Freezing time: 12°C - Freeze-drying temperature: - 87°C - Pressure: 0.0047 mbar

[0137] [Tables2] Powder (M) Total concentration (in the mother solution) of phytic acid + sodium metasilicate Ml 1% M2 5% M3 10% M4 15% M5 35% M6 35% M7 10% M8 35%

[0138] (as a reminder:

[0139] - powder obtained by atomization: M1-M5,

[0140] - powder obtained by freeze-drying: M6-8)

[0141] Characterization of the powder: • Color: white-grey • Appearance: granular to lumpy • Spherical particle • Morphology: mixture of smooth spheres and hollow spheres (or dented) • Size / granulometry:

[0142] [Tables3] Material (M) DvlO (pm) Dv50 (pm) Dv90 (pm) SEM observation dry Ml 1.4 2.2 3.6 500 nm-3pm M2 1.8 5.1 7.1 500 nm-4pm M3 4.6 9.9 24.6 1-50 pm M4 6.8 10.8 15.3 1-40 pm M5 1.2 2.3 7 1-40 pm

[0143] Stability: the obtained powder M1-M8 is stable in dispersion at 1% in water (pH = 3.4, and no change in viscosity was observed.

[0144] Example 1: Preparation of compositions according to the invention and comparative compositions Example A1 and A2 (comparative)

[0145] This example is prepared by diluting the aqueous solution of aluminum chloride, sold under the name "#CHLORHYDROL 50#" to 50% active matter (hereinafter "MA") by the company "#SUMMITREHEIS#" to obtain a solution respectively at 5% MA (Al) and a solution at 15% MA (A2) at a spontaneous pH around 3.8. Example B1 and B2 (comparative)

[0146] This example is prepared from potassium alum crystals: potassium / aluminium sulfate, 12 H2O, sold under the name “#POTASSIUM ALUM PH EUR#” by the company “OKER CHEMIE#” to obtain a 1 and 5% MA solution at a respective pH of 3.5 and 3.2. Example Cl to CIO

[0147] Examples C1 to C10 are prepared according to the following protocol: a solution C1 is prepared by dispersing a powder M1 at the concentration indicated in the table below and made up to 100% with osmosis water after magnetic stirring for 30 seconds.

[0148] Example 2: In vitro evaluation of the antiperspirant activity of the compositions of Example 1

[0149] The microfluidic method used is detailed in document WO 2014 / 170174. This tool makes it possible to qualitatively evaluate a potential antiperspirant activity by physicochemical means of an active ingredient that mimics aluminum salts (ACH). It makes it possible to create an in-vitro system modeling the physics and consequently the specificity of sweat flows as they occur in vivo. Consequently, it makes it possible to qualitatively observe (formation of flocs, aggregates and plugs, etc.) between the active ingredients in solution and the constituents of sweat under sweating-mimicking conditions. Thus, the formation of a plug in contact with the channels containing, on the one hand, the sweat, and on the other hand, the compound to be evaluated indicates that the compound to be evaluated effectively blocks the passage of sweat and consequently has antiperspirant activity.

[0150] In the test selected, the microsystem manufactured in PDMS (polydimethylsiloxane) comprises a main channel intended to accommodate the antiperspirant (55 pm in height and 400 pm in width) and a straight channel (55 pm in height and 300 pm in width) into which an artificial sweat model containing various concentrations of CaCl2 and at various pHs is injected, mimicking the sweat channel. Once the microsystem is tightly closed, the flows are controlled using a syringe pump. The sweat flow rate setpoint is 0.1 nL / s, and that of the antiperspirant channel is 1 nL / s. Once the steady state is established, the fluids flow at a controlled flow rate in a laminar regime and their interactions are observed by optical microscopy. An image is recorded every 15 seconds for 30 minutes.

[0151] A synthetic sweat was prepared as follows:

[0152] [Tables4] NAME SWEAT % by weight Sodium Chloride 0.5% Lactic Acid 0.5% Urea 0.5% Ammonium Hydroxide Qsp pH 6.5 Bovine Serum Albumin (BSA) 0.5% CaC12 2 mM Water Qsp 100%

[0153] The compositions of Examples A, B1, B2 and C1 to C10 were evaluated in the microfluidic system with synthetic sweat of the composition detailed above.

[0154] [Tables5] Ex Active tested (M) Concentration in M ​​(%) Solvent pH in aqueous dispersion Depth of the plug (mm) Thickness of the plug (mm) Comment Al Aluminum chloride 5 Water 40 Plug in the southern oral canal A2 Aluminum chloride 5 Water 60 Plug in the southern oral canal B1 Aluminum stone (48P) 1 Water 3.5 - - No blockage B2 Aluminum stone (48P) 5 Water 3.2 - - No blockage Cl Ml 1 Water 3 8 46 Blockage slightly outside the sweat duct C2 Ml 5 Water 2.5 32 53 Blockage in the oral sudoral canal C3 M2 1 Water 3.1 1 52 Blockage slightly outside the sweat duct C4 M2 5 Water 2.7 31 53 Blockage in the oral sudoral canal C5 M3 1 Water 3.3 6 46 Blockage slightly outside the sweat duct C6 M3 5 Water 2.8 45 55 Blockage in the oral sudoral canal C7 M4 1 Water 3.5 - - Plug outside the sweat canal C8 M4 5 Water 3.1 5 50 Plug in the sweat canal C9 M5 1 Water 3.4 21 41 Plug in the sweat canal CIO M5 5 Water 3 32 60 Plug in the southern oral canal

[0155] It is found that, in this model test of the sweat canal, the application of compositions C2, C4, C6 and C8 to CIO under the conditions tested, leads to the formation of a plug, as observed for the aluminum salts (compositions A 1 and A2). The other compositions C1, C3, C5, C7 lead to the formation of a plug in the membrane and slightly on the outside. The existence of a plug characterizes good antiperspirant properties.

[0156] Comparative compositions B1 and B2, under the conditions tested, do not lead to the formation of a plug.

[0157] These results demonstrate the advantage of using a powder according to the invention of particles each comprising the combination of disodium metasilicate with at least one chelating compound chosen from phosphonic derivatives and amino acids.

Claims

Claims

1. Cosmetic powder, in particular for preventing and / or treating perspiration, in which the particles comprise: - at least one alkali metal metasilicate and - at least one chelating compound chosen from the phosphonic derivatives of the following formula (I): [Chem.l] (I) where R represents an alkyl radical, linear or branched, cyclic or non-cyclic, saturated or unsaturated, comprising from 1 to 10 carbon atoms, and n represents an integer between 1 and 10, and amino acids; characterized in that the weight ratio between said metasilicate and said chelating compound is in the range from 0.1 to 1; and characterized in that it has a pH in aqueous dispersion in the range from 2 to 5; and characterized in that it comprises particles in which said metasilicate and said chelating compound are present within the same particle, and the particles have a volume median diameter in the range from 1 to 20 pm.

2. Powder according to claim 1, characterized in that the phosphonic derivatives of formula (I) are such that R represents a saturated cyclic linear alkyl radical, comprising from 1 to 10 carbon atoms, preferably from 4 to 8 carbon atoms, preferably between 5 and 7 carbon atoms, and n represents an integer between 1 and 10.

3. Powder according to claim 1 or 2, characterized in that the alkali metal metasilicate is an anhydrous compound of formula M2 SiO3, or a hydrated compound of general formula M2SiO3.nH2O, M being an alkali metal chosen from Li, Na and K and n varying from 1 to 10, preferably the alkali metal metasilicate is disodium metasilicate.

4. Powder according to one of claims 1 to 3, characterized in that the chelating compound is chosen from phytic acid, serine, O-phosphoserine and histidine.

5. Powder according to any one of the preceding claims, characterized in that it comprises at least one alkali metal metasilicate and at least two different chelating compounds chosen from phosphonic derivatives of formula (I) and amino acids.

6. Powder according to any one of the preceding claims, characterized in that the particles have a volume median diameter in the range of 2 to 15 qm.

7. Powder according to any one of the preceding claims, characterized in that it comprises particles in which said metasilicate and said chelating compound coexist within a particle, preferably exist separately, preferably without a covalent bond connecting them, within the same particle.

8. Powder according to claim 7, characterized in that it comprises, on the total weight of powder, at least 50%, preferably at least 60%, preferably at least 70%, preferably at least 80%, preferably at least 90%, preferably at least 95%, by weight, of particles in which said metasilicate and said chelating compound are present within the same particle.

9. Powder according to any one of the preceding claims, characterized in that the weight ratio between said metasilicate and said chelating compound is in the range of 0.2 to 0.7, preferably 0.3 to 0.6, preferably 0.4 to 0.6, preferably 0.5

10. Powder according to any one of the preceding claims, characterized in that it comprises particles of spherical shape, at least partially dented.

11. Powder according to any one of the preceding claims, characterized in that it has a pH in aqueous dispersion in the range from 2 to 4, preferably from 2.5 to 3.5, preferably from 2.7 to 3.2, preferably from 2.7 to 2.

9.

12. A method of manufacturing a powder according to any one of the preceding claims, characterized in that it comprises a step of atomizing or lyophilizing an aqueous solution containing said metasilicate and said chelating compound, and recovering the powder.

13. A method according to claim 12, wherein said aqueous solution has a total concentration of metasilicate(s) and chelating compound(s) of at least 1%, preferably within the range of 1 to 40%, preferably 1 to 30%, preferably 1 to 20%, by weight of the total weight of the composition.

14. A method according to any one of claims 12 or 13, wherein said aqueous solution has a pH in the range of 2 to 5, preferably 2 to 4, preferably 2.5 to 3.5, preferably 2.7 to 2.

9.

15. Process according to any one of claims 12 to 14, characterized in that the weight ratio between said metasilicate(s) and said chelating compound(s) in said aqueous solution is in the range of 0.1 to 1, preferably 0.2 to 0.7, preferably 0.3 to 0.6, preferably 0.4 to 0.6, preferably 0.5

16. Method according to any one of claims 12 to 15, characterized in that it further comprises a homogenization or grinding step after said atomization or freeze-drying step.

17. Cosmetic composition, in particular for preventing and / or treating perspiration, comprising, in a cosmetically acceptable medium, at least one powder according to any one of claims 1 to 11.

18. Composition according to claim 17, characterized in that it has a pH in the range from 2 to 5, preferably greater than or equal to 2 and less than 5, preferably, said pH is in the range from 2 to 4, preferably from 2.5 to 3.5, preferably from 2.7 to 3.2, preferably from 2.7 to 2.

9.

19. Composition according to claim 17 or 18, characterized in that it is in one of the following forms: compact powder, stick, soft-solid, gel, emulsion, aqueous or oily dispersion, roll-on, aerosol or spray.

20. Cosmetic process for preventing and / or treating perspiration, characterized in that it comprises bringing a keratin material, preferably the skin, into contact with at least one powder as defined according to any one of claims 1 to 11, or with a composition according to any one of claims 17 to 19.