An emulsified composition comprising an oil-in-water emulsifier and cyclodextrin of a selected particle size, providing an oil-in-water emulsion that can be used in cosmetics and improves the sensory experience

Abstract

The present invention relates to a sensory emulsifying composition dedicated to cosmetics, capable of obtaining an oil-in-water emulsion which comprises at least one cyclodextrin in the form of solid particles, these particles having a volume average size d(4,3) measured by laser granulometry, the volume average size being between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm, and comprising at least one natural-source emulsifier selected from oil-in-water emulsifiers, the natural-source emulsifier having an HLB value greater than or equal to 8, most preferably greater than or equal to 9.

Description

[0001] The present invention relates to an emulsifying composition of plant origin, which can be put into immediate use and directly refrigerated, and can be applied especially in the field of cosmetics. The composition comprises at least one cyclodextrin in the form of solid particles, the particles having a volume average size d(4,3) measured by laser granulometry, which volume average size is less than or equal to 20 μm, and at least one emulsifier of natural origin. The emulsifying composition according to the invention can be used both as a cosmetic composition and as a premix for preparing and stabilizing emulsions. The emulsifying composition is particularly easy to produce a delicate oil-in-water (O / W) emulsion, and the emulsion has various textures according to different skin types. The obtained composition has a soft and powdery texture even when the oil phase in the emulsion is relatively high, and is easy to spread without flocculation.

[0002] An emulsion is a form in which a liquid (or a liquid in which a material is made) is dispersed in the form of fine droplets into another liquid immiscible with the said liquid. An emulsion appears uniform in texture when observed visually, but appears non-uniform when observed under a microscope. The liquid in droplet form is called the dispersed phase (or discontinuous phase), while the other liquid is called the dispersion medium (or continuous phase). Usually, an emulsion consists of two phases (simple emulsion): a hydrophilic (water) phase and a lipophilic (oil) phase. An oil-in-water emulsion is called a direct emulsion.

[0003] Emulsions are widely used in the field of cosmetics. As cosmetics, emulsions must be able to meet the needs of consumers for high efficiency, safety and comfortable sensory characteristics at the same time. In order to meet the above-mentioned sensory characteristics, the formulations of emulsions are becoming increasingly complex because they incorporate more and more functional or sensory components (usually from petrochemical products).

[0004] Most known emulsion-based cosmetic compositions, usually simple emulsions, are stabilized using surfactants. For example, document EP 0 685 227 mentions a complex sunscreen cosmetic composition system, which comprises an aqueous continuous phase, a protection system capable of filtering ultraviolet rays, surfactants, organic solvents (lower alcohols and lower polyols), and at least one polymer, especially a crosslinked copolymer (alkyl acrylate, vinyl acetate). Document FR 2 858 777 describes an oil-in-water emulsion, which comprises at least one oily substance (fatty acid, wax, butter, natural oil - vegetable oil, animal oil, marine oil product, synthetic oil or mineral oil, hydrogenated oil and mixtures thereof), at least one surfactant (ethoxylated polyglycerol ester, alcohol ethoxylate), at least one co-surfactant and water.

[0005] However, the use of surfactants in topical or oral products for human or animal use can have adverse consequences. The reason is that surfactants can damage cell membranes. Therefore, especially in the field of cosmetics, efforts have always been made to reduce the potential harmful effects of surfactants.

[0006] In addition, cosmetics must meet the new expectations of today's consumers: the raw materials of the composition are natural, and even the entire composition must be a natural product. In fact, consumers are now seeking cosmetics mainly composed of natural ingredients or natural raw materials, minimizing the content of chemically modified, synthetic grafted or petrochemical-derived ingredients in cosmetics.

[0007] Moreover, one of the aims of the present invention is to provide a composition which can be dispersed in an aqueous phase even by a "cooling" method and then an oil or fat substance is added to form a stable emulsion. Such a composition can eliminate the dependence on surfactants of petroleum origin and non-biodegradable, especially on ethylene glycol derivatives and ethoxylated derivatives. The composition according to the present invention can also produce Pickering-type emulsions. This type of emulsion does not contain surfactants and is stabilized by colloidal particles (usually silica) placed at the interface between the continuous phase and the dispersed phase. According to the present invention, these colloidal particles are organic particles composed of an inclusion compound between at least one cyclodextrin and at least one fatty molecule. These particles are very suitable for the skin or hair and do not damage cell membranes.

[0008] This effect is very remarkable because the prior art shows that when producing an emulsified cosmetic composition containing cyclodextrin, an emulsion cannot be simply obtained directly under cooling conditions: surfactants of petroleum origin must be used beforehand. It should be noted in particular that according to document EP 2 091 502 B1, an oil-in-water (O / W) emulsion contains water, a fat substance, a modified polysaccharide and cyclodextrin, and the main characteristic of this O / W emulsion is that it contains a surfactant with a molecular weight less than 5000 g / mol and a weight less than 2%. Therefore, it is not clear whether a very fine and stable emulsion can be obtained when preparing an emulsifying system containing cyclodextrin without relying on surfactants of petroleum origin.

[0009] In addition, the main factors attracting cosmetic consumers lie first in the sensory characteristics of cosmetics, and good effects can be directly observed only after use. Therefore, the challenge for cosmetics is to provide significant cosmetic effects while providing as pleasant a user experience as possible before or during the use of cosmetics. However, removing functional or sensory components from petrochemical products, replacing them with natural ingredients or adding new natural ingredients or ingredients of natural origin may reduce the sensory characteristics of the product and more or less significantly affect the characteristics of cosmetics, especially sensory characteristics such as the appearance, formulation, use, and use characteristics on the skin or the outer epidermis of cosmetics. Similarly, a composition meeting the natural standard may be difficult to apply, flocculate or difficult to absorb, and may also feel rough, brittle or even not smooth during use. These imperfect sensory experiences are not conducive to enhancing the quality or appearance of cosmetics.

[0010] The application FR1853362 previously filed by the applicant has not been made public. This application relates to an emulsifying composition that contains cyclodextrin and an emulsifier of natural origin, and the HLB value of this emulsifier is greater than or equal to 8. The β-cyclodextrin used is the β-cyclodextrin sold by Roquette Frères under the trade name "Beauté by CD 102", and its volume average size is equal to 95 μm. However, the sensory properties of the composition used in this application are not perfect.

[0011] Therefore, the object of the present invention is to provide an emulsifying composition for improving cosmetics, which can improve the sensory properties of the product compared with the emulsifying composition involved in the application FR1853362, especially in terms of powdery texture, ease of spreading, soft touch, scratching sensation during application, permeability of the composition, and flocculation.

[0012] Another object of the present invention is to provide a composition of 100% natural origin. Nowadays, whether the ingredients required for formulating common products (such as cosmetic compositions) are of natural origin has become a focus of attention, which is not only related to environmental protection and safety, but also involves the health rights and interests of consumers. The composition according to the present invention can replace surfactants of synthetic origin, especially surfactants of petroleum origin, such as ethoxylated surfactants. Considering the environmental impact, due to the poor biodegradability of the above-mentioned surfactants, safety reasons, and the fact that ethylene oxide, which is widely used in the production of polyethoxylated surfactants, is extremely dangerous, toxic, and flammable, we are trying to replace such surfactants.

[0013] Another object of the present invention is to provide a ready-to-use composition, which is convenient for pharmacists to operate with the lowest energy input, especially by adding all the ingredients to the same mortar or the same reactor (referred to as "one pot" in English). Specifically, the emulsifying composition according to the present invention can be used according to the "cooling method", even at room temperature. The "cooling method" means that the emulsifying composition can be dispersed in water at a temperature below 45°C, more preferably below 35°C, and even preferably at room temperature conditions for direct use.

[0014] Another object of the present invention is to provide a composition that can be widely used in cosmetics, that is, the composition is generally applicable to final product applications: It can be seen therefrom that the composition according to the present invention can be used in various products, such as emulsions, creams, gels, lotions... In addition, the composition is non-irritating to the skin and not prone to allergies. The composition also has the advantage of being independent of pH or electrolytes: In other words, its emulsifying ability is not affected by the pH of the medium or monovalent, divalent or trivalent salts. This criterion is very important because usually cosmetic products, especially those for topical application, are easily affected by pH changes (for example, the pH of the skin is weakly acidic, between 4 and 6). Therefore, the emulsifying composition has no specific use restrictions in terms of pH, which demonstrates the powerful technical advantages of the cosmetic composition.

[0015] The main object of the present invention is to solve complex technical problems, which mainly include an emulsifying composition, especially an emulsifying composition for cosmetics, which can obtain an oil-in-water (O / W) emulsion, specifically including:

[0016] a) at least one cyclodextrin in the form of solid particles, these particles having a volume average size d(4,3) measured by laser particle size analysis, and the volume average size is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm,

[0017] b) and at least one natural source emulsifier selected from water-in-oil emulsifiers, and the hydrophilic-lipophilic balance value of the natural source emulsifier is greater than or equal to 8, more preferably greater than or equal to 9.

[0018] The calculation of HLB takes into account the molecular weight of the hydrophilic part and the molecular weight of the selected molecule, and is calculated according to the following formula:

[0019] [Math.1]

[0020]

[0021] Cyclodextrin

[0022] The composition according to the present invention includes at least one cyclodextrin in the form of solid particles, and the particles have a volume average size d(4,3) measured by laser particle size analysis, and the volume average size is less than or equal to 20 μm, preferably less than or equal to 12 μm, and most preferably less than or equal to 8 μm.

[0023] In this application, the term "cyclodextrin" means and includes any cyclodextrin commonly known to professionals, such as natural and unsubstituted cyclodextrins containing 6 to 12 glucose units connected by covalent bonds between carbon 1 and carbon 4, especially α-, β- and γ-cyclodextrins containing 6, 7 and 8 glucose units respectively.

[0024] The term also includes "cyclodextrin derivatives", i.e., at least a part of the OH hydroxyl groups in the molecule have been converted into OR groups, where R generally represents an alkyl group. It can be seen therefrom that cyclodextrin derivatives particularly include methylated cyclodextrins and ethylated cyclodextrins, but also include cyclodextrins substituted with hydroxyalkyl groups, such as hydroxypropylated cyclodextrins and hydroxyethylated cyclodextrins.

[0025] According to the present invention, the cyclodextrin is preferably α-, β- and γ-cyclodextrins. According to a preferred embodiment, the cyclodextrin in the composition according to the present invention is β-cyclodextrin, preferably "natural" cyclodextrin, i.e., the hydroxyl groups are not chemically substituted.

[0026] Cyclodextrin can also be in the form of crystalline, pseudo-crystalline or amorphous powder.

[0027] According to the present invention, the cyclodextrin is present in solid particles, which are characterized in that these particles have a volume average size d(4,3) (also called particle size) measured by laser particle size analysis, and the volume average size is less than or equal to 20 μm, preferably less than or equal to 12 μm, and most preferably less than or equal to 8 μm. According to a preferred embodiment, the volume average size of the solid particles of cyclodextrin is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, and most preferably between 4 μm and 8 μm.

[0028] The solid particles of cyclodextrin can have any regular or irregular geometric shape, and can be individual cyclodextrin crystals or aggregates of cyclodextrin crystals bridged by crystal bridges. The solid particles of cyclodextrin preferably have a regular geometric shape.

[0029] The volume average size is usually denoted by d(4,3) and is determined according to the volume size distribution of ISO 9276-2:2014 standard, and the volume size distribution can be measured by laser diffraction particle size analysis, for example, using a series of laser particle size analysis techniques, such as Malvern company's "Mastersizer 2000 TM ", "Mastersizer 3000 TM ", "Mastersizer 3000E TM " or company's "Particula LA960" laser particle size analysis technique. According to the guidelines of ISO13320:2009 standard, laser diffraction measurement can be carried out by wet method or dry method. When using the wet method, it is recommended to use 2-propanol as the measuring liquid.

[0030] The cyclodextrin solid particles preferably have a volume size distribution determined by laser diffraction granulometry, and the characteristic diameters d(10), d(50) and d(90) of the volume size distribution are as follows:

[0031] a) The diameter d(10) is between 0.8 μm and 5.0 μm, preferably between 1.0 μm and 2.5 μm, and

[0032] b) The diameter d(50) is between 5 μm and 15.0 μm, preferably between 7 μm and 10.0 μm, and

[0033] c) The diameter d(90) is between 15 μm and 30.0 μm, preferably between 20 μm and 25.0 μm.

[0034] According to the ISO 13320:2009 standard, the characteristic diameters d(10), d(50) and d(90) defined by the symbols x10, x50 and x90 correspond to 10%, 50% and 90% of the particle sizes of the distribution calculated by cumulative volume, respectively.

[0035] According to a preferred embodiment, the cyclodextrin solid particles have a volume size distribution determined by laser diffraction granulometry, and the characteristic diameters d(10), d(50) and d(90) of the volume size distribution are as follows:

[0036] a) The diameter d(10) is less than or equal to 5.0 μm, preferably less than or equal to 2.5 μm,

[0037] b) The diameter d(50) is less than or equal to 15.0 μm, preferably less than or equal to 10.0 μm,

[0038] c) The diameter d(90) is less than or equal to 30.0 μm, preferably less than or equal to 25.0 μm.

[0039] The cyclodextrin solid particles also preferably exhibit a volume size distribution determined by laser diffraction granulometry, and the coefficient of variation of the distribution is less than or equal to 100%, preferably less than or equal to 90%, and most preferably less than or equal to 73%. According to the definition in ISO 13320:2009, the coefficient of variation of the particle size distribution is the standard deviation of the particle size distribution divided by the average size d(4,3) of the volume, also known as the volume average particle size.

[0040] According to this preferred embodiment, the cyclodextrin is in the form of solid particles, and the cyclodextrin size distribution is calculated by volume, and the volume distribution is determined by laser diffraction granulometry, and is characterized in that:

[0041] a) The average volume size d(4,3) is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm,

[0042] b) The coefficient of variation is less than or equal to 100%, preferably less than or equal to 90%, more preferably less than or equal to 73%.

[0043] Due to the selection of specific sizes, the cyclodextrin particles can especially improve softness, thus enhancing the touch feeling. In addition, according to different skin types, using this composition can significantly reduce the scratching sensation and flocculation during application, and even eliminate flocculation.

[0044] Oil-in-water emulsifier of natural origin

[0045] The term "naturally sourced" oil-in-water emulsifier as used in this application refers to any emulsifier obtained from renewable resources, especially extracts or secretions of plants, microorganisms, or algae, and can be used to prepare an oil-in-water emulsion after physical, chemical, or enzymatic modification.

[0046] The hydrophilic-lipophilic balance value (HLB) of the naturally sourced oil-in-water emulsifier is greater than or equal to 8, more preferably greater than or equal to 9. The ratio (weight / weight) of the oil-in-water emulsifier / cyclodextrin in the emulsifying composition is preferably between 0.01:1 and 1:1, preferably between 0.05:1 and 0.5:1, more preferably between 0.10:1 and 0.35:1, and most preferably between 0.15:1 and 0.30:1.

[0047] The hydrophilic-lipophilic balance value of this naturally sourced O / W emulsifier is preferably between 8 and 20, more preferably between 9 and 16, and most preferably between 11 and 14. It can also be a product selected to be biodegradable naturally in a hydrated natural environment.

[0048] In particular, the average HLB value of the entire emulsifying system of the composition is greater than or equal to 8, preferably greater than or equal to 9. The average HLB value of the entire emulsifying system of the composition is a weighted average calculated by reading the HLB values of each emulsifier, that is, the result obtained by calculating the mass fraction of the total mass of the emulsifier.

[0049] The oil-in-water (O / W) emulsifier is preferably selected from natural raw materials, such as the following products that meet the above HLB conditions: alkyl polyglycosides, a mixture of at least one alkyl polyglycoside and at least one fatty alcohol, non-ethoxylated fatty acid esters of polyols, especially non-ethoxylated fatty acid esters of glycerol, ethylene glycol, sorbitol, sorbitan, tetrahydrohexitols (especially isosorbide, mannitol, xylitol, erythritol, maltitol, sucrose, glucose, polydextrose, hydrogenated glucose syrup, dextrin, and hydrolyzed starch).

[0050] O / W emulsifiers of natural origin are preferably selected to undergo natural biodegradation in a hydrated natural environment. These emulsifiers can be non-ethoxylated fatty acid esters of polyols obtained from free fatty acids or by transesterification of oils or oil mixtures. The fatty acids used contain 8 to 22 carbon atoms, preferably 10 to 18 carbon atoms, and particularly preferably 12 to 18 carbon atoms. The acids can be straight-chain or branched-chain, saturated or unsaturated, and carry one or more side hydroxyl functional groups. The oils can be saturated or unsaturated, liquid or solid at room temperature, and can carry hydroxyl functional groups, preferably with an iodine value between 1 and 145, and particularly preferably between 5 and 105.

[0051] O / W emulsifiers of natural origin can be particularly selected from polyglycerol fatty acid esters, preferably fatty acid esters produced from the reaction of polyglycerol, which contain 2 to 12 units of glycerol, preferably 3 to 10 units of glycerol, and are reacted with at least one partially hydrogenated or non-hydrogenated vegetable oil with an iodine value between 1 and 15, and particularly preferably between 5 and 10. The above emulsifiers can especially be oleates, stearates, palmitates, laurates, diisostearates, and caprylates of polyglycerol, especially the following products: polyglycerol-5 dioleate, HLB is about 8 (e.g., G 5 Do from Evonik Dr.StraetmansGmbH), polyglycerol-2 caprylate, HLB value is preferably about 9 (e.g., PGC.2 from HYDRIOR), polyglycerol-3 stearate, preferably HLB is about 9 (e.g., PGPR from Evonik Dr.StraetmansGmbH), polyglycerol-2 laurate, preferably HLB is about 9 (e.g., G2L from Evonik Dr.StraetmansGmbH), polyglycerol-3 palmitate, preferably HLB is about 10 (e.g., PP from EvonikDr.Straetmans GmbH), polyglycerol-10 diisostearate, preferably HLB is about 11 (e.g., G10 DI from Evonik Dr.Straetmans GmbH), polyglycerol-6 caprylate, preferably HLB is about 11.5, polyglycerol-5 laurate, preferably HLB is about 13 (e.g., G5L from Evonik Dr.Straetmans GmbH), polyglycerol-3 caprylate, preferably HLB is about 14 (e.g., PGC.3), polyglyceryl-4 decanoate, preferably with an HLB of about 14 (e.g., MASSOCARE PG4 C from Masso), polyglyceryl-10 monolaurate, preferably with an HLB of about 14.8, polyglyceryl-6 caprylate, preferably with an HLB of about 15 (e.g., G 6 CY from Evonik Dr. Straetmans GmbH), polyglyceryl-10 laurate, preferably with an HLB of about 16 (e.g., G 10L from Evonik Dr. Straetmans GmbH).

[0052] O / W emulsifiers of natural origin are preferably selected from alkyl polyglycosides, also known as alkyl polyglycosides, abbreviated as APG. These emulsifiers are various known nonionic surfactants. The structure of the above emulsifiers is described in the patent FR 2 948 285, and the preparation method is explained. These emulsifiers can be represented by the following general formula (I): R1-O-(R2-O)p-(S)n, where:

[0053] -S represents a reducing sugar, which may contain 5 to 6 carbon atoms,

[0054] -R1 represents a straight-chain or branched-chain alkyl and / or alkenyl group, preferably containing about 8 to 24 carbon atoms; or an alkylphenyl group, where the straight-chain or branched-chain alkyl group preferably contains about 8 to 24 carbon atoms,

[0055] -R2 represents an alkylene group containing 2 to 4 carbon atoms,

[0056] -n represents a value between 1 and 15,

[0057] -p represents a value between 0 and 10.

[0058] A reducing sugar means that in formula (I), the sugar derivative does not show a glycosidic bond established between the anomeric carbon and the oxygen of the acetal group in its structure. See the definition in the reference book: "Biochemistry", Daniel Voet / Judith G. Voet, page 250, John Wyley & Sons, 1990. The oligomeric structure (S)n can be in any form of isomerism, such as optical isomerism, geometric isomerism or positional isomerism; it can also represent a mixture of isomers.

[0059] According to a specific embodiment of the present invention, in the definition of the compound of formula (I), S represents a reducing sugar selected from glucose, dextrose, sucrose, fructose, idose, gulose, galactose, maltose, isomaltose, maltotriose, lactulose, cellobiose, mannose, ribose, xylose, arabinose, lyxose, allose, altrose, dextran or talose, especially a reducing sugar selected from glucose, xylose or arabinose.

[0060] The first preferred variant of the alkyl polyglycoside according to the present invention is a C12-C20 alkyl polyglycoside, i.e., a compound of formula (I), wherein:

[0061] - R1 particularly represents a straight-chain or branched-chain alkyl and / or alkenyl containing about 12 to 20 carbon atoms,

[0062] - R2 represents an alkylene containing 2 to 4 carbon atoms,

[0063] - p is a value between 0 and 3, preferably equal to 0,

[0064] - S represents glucose, fructose or galactose, preferably glucose

[0065] The second preferred variant of the alkyl polyglycoside according to the present invention is a C12-C20 alkyl polyglycoside of the compound of formula (I), wherein:

[0066] - R1 particularly represents a straight-chain alkyl containing about 12 to 20 carbon atoms

[0067] - p is zero,

[0068] - S represents glucose

[0069] The alkyl polyglycoside of formula (I) can especially be the following commercial products: those sold by BASF 810UP (R1 is C8-C10 / INCI: octyl / octyl glucoside), 818UP (R1 is C8-C16 / INCI: coco glucoside), 2000UP (R1 is C8-C16 / INCI: decyl glucoside) and 1200UP (R1 is C12-C16 / INCI: lauryl glucoside); those of FCI Technology 810 (R1 is C8-C10), 1200 (R1 is C12-C14), 816 (the mixture of R1 is C8, C10, C12, C14 and C16); Neocare MF 0718 sold by Neochem (R1 is C8-C10 / INCI: Octyl / Octyl Glucoside), Neocare MF 0012 (R1 is C12-C14 / INCI: Lauryl Glucoside), Neocare MF 0002 (R1 is C8-C16 / INCI: Decyl), Neocare MF 818 (R1 is C8-C16 / INCI: Coco-Glucoside); Tego Care CG 90 sold by Evonik Healthcare (R1 is C14-C16 / INCI: Cetearyl Glucoside).

[0070] The O / W emulsifiers of natural origin are preferably mixtures composed of at least one alkyl polyglycoside and at least one fatty alcohol. Among these mixtures, the alkyl polyglycosides can be selected from all the alkyl polyglycosides applied to the present invention above. The fatty alcohols that can be mixed with the alkyl polyglycosides will be straight-chain or branched-chain fatty alcohols with the total number of carbon atoms between 8 and 24.

[0071] The mixtures of alkyl polyglycosides and fatty alcohols that can be used in the present invention are the following products sold by SEPPIC: Montanov TM 14 (INCI: Myristyl Alcohol and Myristyl Glucoside), Montanov TM 202 (INCI: Arachidyl Alcohol and Behenyl Alcohol and Arachidyl Glucoside), Montanov TM 68 (INCI: Cetearyl Alcohol and Cetearyl Glucoside), Montanov TM 82 (INCI: Cetearyl Alcohol and Coco-Glucoside), Montanov TM S (INCI: Coco-Glucoside and Cetearyl Alcohol), Montanov TM L (INCI: C14-22 Alcohols and C12-20 Alkyl Glucosides).

[0072] The mixture of alkyl polyglycoside and fatty alcohol is preferably "Montanov TM L" sold by SEPPIC, which is a mixture of C14-C22 fatty alcohols and C12-C20 alkyl polyglycosides (INCI: C14-22 Alcohols and C12-20 Alkyl Glucosides).

[0073] Thus, a preferred variant of the emulsifying composition according to the present invention comprises a mixture consisting of at least one alkylpolyglycoside and at least one fatty alcohol as an oil-in-water emulsifier of natural origin, preferably comprising at least one C12-C20 alkylpolyglycoside and at least one linear or branched fatty alcohol with a total number of carbon atoms between 8 and 24, and most preferably comprising a mixture of C14-C22 fatty alcohols and C12-C20 alkyl glycosides.

[0074] The O / W emulsifier of natural origin can also be selected from fatty esters of dextrin or hydrolyzed starch, especially sodium octenyl succinate. For example, products sold by the applicant under the name, especially product CO 01 and CO 03.

[0075] Influence produced by cyclodextrin particle size selection

[0076] Compared with an emulsifying composition containing cyclodextrin with a volume average size greater than or equal to 90 μm, such as the cyclodextrin "Beauté by CD 102" sold by Roquette Frères, the emulsifying composition according to the present invention can easily obtain an emulsion that is easy to disperse, making the emulsion more powdery, with a softer texture, lower brittleness, stronger permeability on keratin materials, and almost no flocculation. According to the different proportions used, the emulsifying composition according to the present invention can also obtain a surprising sensory experience, such as a special texture or freshness.

[0077] The above advantages of the emulsifying composition are produced by the combination of the two compounds used, which work together to ensure the stability and good sensory properties of the emulsion. Very satisfactory effects can be obtained regardless of which mixing ratio of the compounds is selected, but even more impressive effects can be obtained if the mixing is carried out at a more precise ratio.

[0078] In particular, before emulsification, various different components in the emulsifying composition according to the present invention can be integrated into different phases of the final emulsion. Alternatively, the various compounds of the composition according to the present invention are mixed together to form a premix (the English term is premix), which can be added to any phase of the emulsion that will use the premix. The present invention also allows the same compounds to be used in two embodiments, thus increasing practicality and simplifying operation.

[0079] The emulsifying composition according to the present invention particularly has the following advantages: the raw materials are natural and can be used according to the "refrigeration" method (i.e., at room temperature). The composition according to the present invention, especially the composition for cosmetics, is insensitive to slight changes in the pH value or salinity of the medium, non-irritating and not likely to cause allergies, especially skin allergies. In addition, the composition according to the present invention can be used to produce any type of emulsion, especially Pickering emulsions, and thus can be widely used in: creams, lotions, serums, lotions, etc.

[0080] Water

[0081] The emulsifying composition may contain water in the "constituted or bound" form and / or in the "free" form. The constituted or bound water consists of the water molecules contained in the crystal structure of cyclodextrin and / or polyol powder and the water molecules adsorbed on the powder surface through physical hydration equilibrium. The free water consists of the water molecules that can move freely between the cyclodextrin and / or polyol powder. This free water can especially suspend the cyclodextrin and / or polyol powder.

[0082] According to one embodiment, the emulsifying composition contains water or bound water, and its content accounts for 1% to 25% of the total weight of the emulsifying composition. The content of the constituted or bound water is preferably between 2% and 15%, and most preferably between 3% and 10%.

[0083] According to one embodiment, the emulsifying composition may contain free water, and its content is less than or equal to 50% of the total weight of the emulsifying composition. The content of the free water is preferably less than or equal to 40%, more preferably less than or equal to 30%, and most preferably less than or equal to 20%.

[0084] Polyol

[0085] According to one embodiment, the emulsifying composition further contains at least one polyol.

[0086] The polyols referred to in this application are various known polyols, especially maltitol, mannitol, xylitol, erythritol, sorbitol, glycerol, preferably glycerol and sorbitol. The polyol preferably exists in the form of crystals or powder.

[0087] Therefore, the present invention relates to an emulsifying composition, especially an emulsifying composition for cosmetics, which can obtain an oil-in-water (O / W) emulsion, specifically including or preferably consisting of:

[0088] 1) At least one cyclodextrin in the form of solid particles, accounting for 40% to 95% of the total weight of the composition. These particles have a volume average size d(4,3) measured by laser particle size analysis, and this volume average size is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm.

[0089] 2) At least one natural emulsifier selected from oil-in-water emulsifiers, accounting for 5% to 40% of the total weight of the composition. The HLB value of this natural source emulsifier is greater than or equal to 8, and the HLB value of alkyl polyglycoside is preferably greater than or equal to 9.

[0090] 3) And at least one polyol, accounting for 0% to 40% of the total weight of the composition.

[0091] The emulsifying composition according to the present invention comprises or preferably consists of:

[0092] 1) At least one cyclodextrin in the form of solid particles, accounting for 45% to 85% of the total weight of the composition. These particles have a volume average size d(4,3) measured by laser particle size analysis, and this volume average size is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm.

[0093] 2) At least one natural emulsifier selected from oil-in-water emulsifiers, accounting for 5% to 30% of the total weight of the composition. The HLB value of this natural emulsifier is greater than or equal to 8, and the HLB value of alkyl polyglycoside is preferably greater than or equal to 9.

[0094] 3) And at least one polyol, accounting for 10% to 40% of the total weight of the composition.

[0095] The composition according to the present invention more preferably comprises or consists of:

[0096] 1) At least one cyclodextrin in the form of solid particles, accounting for 40% to 80% of the total weight of the composition. These particles have a volume average size d(4,3) measured by laser particle size analysis, and this volume average size is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm.

[0097] 2) At least one natural emulsifier selected from oil-in-water emulsifiers, accounting for 10% to 20% of the total weight of the composition. The HLB value of this natural emulsifier is greater than or equal to 8, and the HLB value of alkyl polyglycoside is preferably greater than or equal to 9.

[0098] 3) And at least one polyol, accounting for 10% to 30% of the total weight of the composition.

[0099] Among the three preferred embodiments of the above emulsion composition, the oil-in-water emulsifier of natural origin is preferably selected from: at least one alkyl polyglycoside; or a mixture of at least one alkyl polyglycoside and at least one fatty alcohol; or an unethoxylated fatty ester of at least one polyol. The emulsifier is more preferably selected from the mixture of at least one alkyl polyglycoside and at least one fatty alcohol.

[0100] Emulsion using the emulsifying composition, preferably Pickering emulsion

[0101] The emulsion composition according to the invention can be used to prepare an emulsion, preferably a Pickering emulsion, which can be stabilized by organic particles suitable for the skin or hair. The above-mentioned "Pickering" emulsion can be obtained by replacing the surfactant with an emulsifying system composed of a combination of solid particles and fatty substances.

[0102] Without being bound by theory, it seems that only a very small amount of the natural oil-in-water emulsifier is needed to greatly promote the formation of an inclusion complex between cyclodextrin and certain specific molecules in the dispersed oil phase, and this inclusion complex can exist in the form of colloids or solid particles at the interface between the oil phase and the water phase. The physical and sensory properties of these particles are very suitable for the skin or hair and do not damage the cell membrane.

[0103] A composition of cyclodextrin and a small amount of oil-in-water emulsifier of natural origin, the hydrophilic-lipophilic balance value of the emulsifier is greater than or equal to 8, more preferably greater than or equal to 9, so as to obtain a very stable emulsion with a droplet size less than 30 μm, even less than 10 μm.

[0104] The emulsion composition according to the invention may further comprise other products capable of forming or stabilizing a Pickering emulsion, such as silica in the form of calcium salts or aluminum salts and octenyl succinic anhydride modified starch.

[0105] Therefore, another object of the present invention relates to an emulsion, preferably a Pickering oil-in-water (O / W) emulsion, especially an emulsion for cosmetics, which is characterized in that it contains at least one cyclodextrin in the form of solid particles, these particles have a volume average size d(4,3) measured by laser particle size analysis, and this volume average size is less than or equal to 20 μm, more preferably between 2 μm and 20 μm, more preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm, and at least one natural emulsifier, the HLB value of the natural emulsifier is greater than or equal to 8, more preferably greater than or equal to 9, and the emulsifier / cyclodextrin (weight / weight) ratio is between 0.01:1 and 1:1, preferably between 0.15:1 and 0.30:1. The emulsifier of natural origin is preferably selected from alkyl polyglycosides, a mixture of at least one alkyl polyglycoside and at least one fatty alcohol, and unethoxylated fatty esters of polyols.

[0106] The emulsion prepared from the emulsifying composition according to the present invention, in particular a Pickering emulsion, additionally comprises an aqueous phase consisting of water.

[0107] According to the "water-rich" embodiment, the water content in the emulsion accounts for 50% to 95% of the total weight of the emulsion, preferably between 60% and 92%, and most preferably between 65% and 90%. According to this embodiment, the emulsion can be used immediately and thus can be used without the user adding additional water.

[0108] According to the "water-deficient" embodiment, the water content in the emulsion accounts for 2% to 50% of the total weight of the emulsion, preferably between 5% and 35%, and most preferably between 10% and 40%. The advantage of the emulsion according to this embodiment is that the total mass of the container, such as a flask, a retort or a mortar, is reduced by reducing the mass of water in the emulsion. This not only reduces the transportation cost but also decreases the amount of exhaust gas emitted during transportation. The user may need to add water during use to ensure the correct implementation of this embodiment.

[0109] The emulsion prepared from the emulsifying composition according to the present invention, in particular a Pickering O / W emulsion, may also comprise an oil phase which can be in a liquid state (such as vegetable oil) or in a solid state (such as wax) at room temperature (25 °C). The liquid oil phase can be a mineral oil, an animal oil, a vegetable oil or a synthetic oil and consists of a hydrocarbon oil or even a silicone oil. The term "hydrocarbon-based oil" should be understood as an oil formed or even composed essentially of carbon and hydrogen atoms, sometimes also oxygen and nitrogen atoms, and may contain alcohols, esters, ethers, carboxylic acids, amines and / or amides.

[0110] The emulsion prepared from the emulsifying composition according to the present invention may comprise one or more oils, preferably at least one non-volatile liquid oil. The term "non-volatile liquid oil" should be understood as an oil capable of remaining on the skin for at least one hour at room temperature and atmospheric pressure.

[0111] The liquid oil phase also contains one or more non-volatile oils that can lubricate the skin. For example, fatty esters such as cetearyl isononanoate, isocetyl isononanoate, isostearyl isostearate, isopropyl isostearate, isopropyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, isononyl isononanoate, 2-ethylhexyl palmitate, 2-hexyldecyl laurate, 2-octyldecyl palmitate, 2-octyldodecyl myristate or lactate, diethylhexyl succinate, diisostearyl malate, cetin, glyceryl tricaprylate, caprylic / capric triglyceride, glyceryl triisostearate, tocopheryl acetate, higher fatty acids (such as myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, linoleic acid, linolenic acid or isostearic acid), higher fatty alcohols such as oleyl alcohol, vegetable oils (such as avocado oil, camellia oil, hazelnut oil, toon oil, cashew nut oil, argan oil, soybean oil, grape seed oil, sesame oil, corn oil, wheat germ oil, rapeseed oil, sunflower oil, cottonseed oil, jojoba oil, peanut oil, olive oil and their mixtures), vegetable fats (such as shea butter) and camellia fat.

[0112] These oils can be hydrocarbon oils or silicone oils, such as paraffin oil, squalane oil, petrolatum, dimethyl silicone and their mixtures.

[0113] The liquid oil phase may also optionally contain a variety of volatile oils. Volatile oils refer to oils that can evaporate from the skin within one hour at room temperature and atmospheric pressure. Volatile oils can be selected from, for example, silicone oils or triglycerides of short-chain fatty acids to reduce the greasiness.

[0114] The emulsion-type composition prepared from the emulsifying composition according to the present invention, especially the Pickering O / W type emulsion, only contains oils from renewable sources, especially plant-derived oils or butters, preferably essential oils. These oils and butters complement the emulsifying system used in the emulsifying composition. The object of the present invention relates to the emulsifying composition because a very stable emulsion can be obtained by using the emulsifying composition, and the emulsion is bright white and its viscosity can be adjusted. The emulsifying composition according to the present invention can prepare an oil-in-water emulsion with a very high oil content. Such oil-rich O / W emulsions are usually difficult to be gradually stabilized over time by conventional emulsifiers. The oil content of the O / W emulsion prepared by the emulsifying composition according to the present invention is preferably between 10% and 65% of the total weight of the emulsion, more preferably between 20% and 55%. Vegetable oils or plant-derived oils, such as sunflower oil and isopropyl palmitate, can especially obtain stable emulsions without causing emulsification or phase shift.

[0115] The emulsion prepared from the emulsifying composition according to the present invention may contain a rheological agent, which may in particular be a water-phase thickening agent, gelling agent or suspending agent, such as gum arabic, konjac gum, guar gum or derivatives thereof derived from vegetable gums; algal gums extracted from algae, such as alginate gels or carrageenans; microbial gums produced by microbial fermentation, such as xanthan gum, glucomannan, scleroglucan or derivatives thereof; cellulose and its derivatives, such as carboxymethyl cellulose or hydroxyethyl cellulose; starch and its derivatives, such as modified starches, especially acetylated starch, carboxymethylated starch, octenyl succinate starch or hydroxypropylated starch; synthetic polymers, such as polyacrylates or carbomer gums.

[0116] The emulsion prepared from the emulsifying composition according to the present invention contains a rheological agent selected from natural polysaccharides of plant or fermentation origin, which natural polysaccharides may be modified. In particular, an oil-in-water emulsion with extremely fine droplet sizes can be obtained with xanthan gum and its derivatives, even when the emulsion content is less than 1% of the total weight of the emulsion.

[0117] The emulsion prepared from the emulsifying composition according to the present invention preferably has an oil phase dispersed in the water phase, and the average size of the dispersed oil-phase droplets is less than 30 μm, preferably less than or equal to 10 μm.

[0118] The small droplet size reduces the flocculation rate of the emulsion, thus reducing the phase separation rate and improving the stability of the emulsion. The average droplet size is determined by a large number of parameters, and thus is characterized in that the size is controllable and can vary according to different formulations of the emulsifying composition.

[0119] The average droplet size can be measured using a LEICA DMLS optical microscope at a magnification of 10 times, and then at least ten droplets are counted and the average value is calculated.

[0120] The emulsion prepared from the emulsifying composition according to the present invention may also contain a preservative selected from benzyl alcohol, dehydroacetic acid and mixtures thereof.

[0121] The emulsion prepared from the emulsifying composition according to the present invention preferably has a viscosity greater than 3000 mPa·s at 25 °C, more preferably a viscosity greater than 5000 mPa·s at 25 °C. The viscosity is measured using a Brookfield DV-II+Pro viscometer, which rotates at a speed of 20 revolutions per minute and contacts the product sample. The resistance received by the product during the rotational motion within one minute is recorded, and the result is converted to the unit of "pascal second", usually denoted as mPa·s. The viscosity of each sample is measured three times, and the average value of the three values is retained.

[0122] To describe the sensory properties of the emulsifying composition according to the present invention, we used sensory indices and a corresponding five-step sensory evaluation protocol. These five steps respectively correspond to different usage stages of skin care products: appearance, handling, use, application 1 minute after application, and application 2 minutes after application. During these five stages, a panel of ten assessors evaluated several sensory indices in order to compare the emulsion according to the present invention with the emulsion according to patent application FR1853362 filed by the present applicant. The differences in sensory properties between the emulsion according to the present invention and the emulsion according to patent FR1853362 lie in: fluidity, degree of comminution, spreadability, greasiness, softness, crispness, permeability, and flocculation. The texture of the emulsion according to the present invention is not smooth, but it is easier to spread and penetrate, feels greasier, is more powdery, softer, and has a lower degree of crispness. Additionally, depending on the skin type, the emulsion has less flocculation or even no flocculation.

[0123] Furthermore, the emulsifying composition according to the present invention can easily prepare an oil-in-water O / W emulsion with high stability, delicate texture, soft touch, and fresh and smooth feel, even when the oil phase in the emulsion is relatively high. Therefore, an emulsion with good moisturizing effect and good moisturizing effect on the skin surface can be obtained.

[0124] In particular, the emulsifying composition can prepare a delicate O / W emulsion with diverse textures, suitable for the skin, dry touch, fresh and smooth feel, and even with a high oil phase content.

[0125] Method for producing an emulsion using the emulsifying composition

[0126] Another object of the present invention includes a method for manufacturing an oil-in-water emulsion, preferably a Pickering emulsion, which is particularly suitable for cosmetics, including the following steps:

[0127] a) Dispersing an emulsifying composition containing at least one cyclodextrin in the form of solid particles in the aqueous phase. These particles have a volume average size d(4,3) measured by laser particle size analysis, and this volume average size is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm, and contain at least one natural source emulsifier from an oil-in-water emulsifier, and the HLB value of this natural source emulsifier is greater than or equal to 8, preferably greater than or equal to 9; the ratio of emulsifier / cyclodextrin is between 0.01:1 and 1:1, preferably between 0.15:1 and 0.30:1,

[0128] b) Adding the oil phase to the mixture obtained in step a). The weight of the oil phase is 10% to 65% of the total weight of the composition. After stirring to disperse the oil phase in the aqueous phase, the average size of the dispersed oil phase droplets is less than 30 μm, preferably less than or equal to 10 μm.

[0129] According to a variant, the oil-in-water emulsion prepared by the method according to the invention, preferably a Pickering emulsion, is particularly suitable for cosmetics and comprises the following steps:

[0130] a) Dispersing an emulsifying composition comprising at least one cyclodextrin in the form of solid particles in the oil phase, these particles having a volume average size d(4,3) measured by laser granulometry, which volume average size is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm,

[0131] and comprising at least one emulsifier of natural origin selected from oil-in-water emulsifiers, the hydrophilic-lipophilic balance value of this emulsifier of natural origin being greater than or equal to 8, preferably greater than or equal to 9, the ratio of emulsifier / cyclodextrin being between 0.01:1 and 1:1, preferably between 0.15:1 and 0.30:1, the weight of the oil phase being preferably between 10% and 65% of the final weight of the emulsion, preferably between 20% and 55%.

[0132] b) And adding the mixture obtained in step a) to the aqueous phase, after stirring to disperse the oil phase in the aqueous phase, the average size of the dispersed oil phase droplets being less than 30 μm, preferably less than or equal to 10 μm.

[0133] In two variants of the method for preparing the above-mentioned preferred Pickering oil-in-water emulsion, it is preferred to use an emulsifying composition according to the invention, this emulsifier being of natural origin and selected from at least one alkylpolyglycoside, at least one mixture of at least one alkylpolyglycoside and at least one fatty alcohol, and unethoxylated fatty esters of at least one polyol, more preferably selected from the mixture of at least one alkylpolyglycoside and at least one fatty alcohol.

[0134] Use

[0135] The invention also has the following uses:

[0136] - A cyclodextrin in the form of solid particles, these particles having a volume average size d(4,3) measured by laser granulometry, which volume average size is less than or equal to 20 μm, more preferably between 2 μm and 20 μm, more preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm,

[0137] - And at least one emulsifier of natural origin selected from oil-in-water emulsifiers, the hydrophilic-lipophilic balance value of this emulsifier of natural origin in the cosmetic liquid emulsion being greater than or equal to 8, most preferably greater than or equal to 9, the hydrophilic-lipophilic balance value of the entire emulsifying system of the composition being greater than or equal to 8, more preferably greater than or equal to 9,

[0138] So as to make the emulsion texture of the emulsion cosmetic softer, powdery and reduce or eliminate flocculation. Examples

[0139] The present invention can be better illustrated by the following non-limiting examples.

[0140] Example 1: Emulsion

[0141] The following two emulsions were compared: one was a "reference" emulsion prepared using an emulsifying composition containing β-cyclodextrin, where β-cyclodextrin was sold by the applicant under the trade name "Beauté CD102", with an average particle size of β-cyclodextrin of 94.83 μm; the other was an emulsion according to the present invention, which also used the same pre-dry-milled β-cyclodextrin with a volume average size d(4,3) of less than 12 μm: thus β-cyclodextrin was characterized as "ultrafine particles". Table 1 lists the particle size characteristics of these two β-cyclodextrins.

[0142] [Table 1]

[0143]

[0144] [Table 2]

[0145] Component Type Reference Invention Beautéby Roquette CD102 β-Cyclodextrin 5％ - β-Cyclodextrin "ultrafine particles" β-Cyclodextrin - 5％ Sunflower seed Oil 30％ 30％ <![CDATA[Montanov TM L]]> Emulsifier 1％ 1％ Hydroxyethyl cellulose Thickener 0.7％ 0.7％

[0146] The two emulsions in Table 2 above were prepared according to the following scheme.

[0147] First, the thickener was dispersed in water while being stirred at a speed of 1000 revolutions per minute with an anti-flocculation blade. When the gelling agent was xanthan gum, the water temperature was set at 40 °C, and when the gelling agent was hydroxyethyl cellulose, the water temperature was set at 70 °C.

[0148] Then, β-cyclodextrin was wetted in glycerol, and the β-cyclodextrin / glycerol mixture was added to the water / gelling agent mixture and stirred at a speed of 1000 revolutions per minute to obtain the aqueous phase.

[0149] The amount of β-cyclodextrin was set at 5% of the weight of the composition.

[0150] In addition, alkyl polyglycoside MONTANOV L (INCI: cetearyl alcohol and cetearyl glucoside) from SEPPIC was magnetically stirred and added to sunflower oil or isopropyl palmitate to obtain the oil phase at 40 °C.

[0151] Subsequently, the oil phase was emulsified in the aqueous phase at 40 °C while stirring at a speed of 1500 revolutions per minute for 15 minutes.

[0152] Add preservatives (a mixture of benzyl alcohol and dehydroacetic acid).

[0153] Measure the physical and chemical properties of each emulsion to understand the droplet viscosity and average size, and evaluate the sensory properties, such as the smoothness, spreadability, greasiness, softness, crispness, permeability, pulverization degree, and flocculation degree of the emulsion.

[0154] Measure the viscosity using a Brookfield DV-II+Pro viscometer. An impeller with a fixed size (SP2 to SP7 models of impellers used according to the viscosity level, refer to the equipment instructions) rotates at a speed of 20 revolutions per minute and contacts the prepared sample. Record the resistance suffered by the product during one minute of rotational motion and convert the result to Pascal-second units. Measure the viscosity of each sample three times and retain the average of the three values. The rotor should be suitable for the measured viscosity, and the specific selection is as follows: use the SP3 rotor when the viscosity is less than or equal to 5000 mPa.s, use the SP4 rotor when the viscosity is between 5000 mPa.s and 7000 mPa.s, and use the SP5 rotor when the viscosity is greater than or equal to 7000 mPa.s.

[0155] Measure the average droplet size using an optical microscope at a magnification of 10 times, then count at least ten typical droplets and calculate the average value. Use a LEICA DMLS microscope.

[0156] The sensory characteristics are jointly evaluated by a panel of ten cosmetic texture analysis experts.

[0157] When applying the product, two indicators will be evaluated. Place 50 μL to 100 μL of the product to be tested on the hand and apply it 10 times, then check the product under a lamp.

[0158] - Evaluate the pulverization degree indicator during the second and fifth applications. The finger can slide smoothly on the skin. It can be observed that the product becomes a powdery substance on the skin.

[0159] - Place 50 μL to 100 μL of the product to be tested on the hand and apply it 10 times, then check the product under a lamp to evaluate the spreadability. Spreadability is important because there is almost no resistance when applying the product from the fifth to the tenth application on the hand.

[0160] After applying 10 times, evaluate the last indicator.

[0161] For the next two indicators, first apply 50 μl to 100 μL of the product on the skin and then check it under a lamp after 1 minute.

[0162] - Slide on the skin to evaluate the softness indicator, and the touch should be dry and smooth.

[0163] - Rub back and forth between the thumb and index finger to evaluate the brittleness index. There should be a sense of resistance and a cracking sound should be heard.

[0164] For the next two indicators, 50 μl to 100 μL of the product should be applied to the skin first, and then checked under a lamp after 2 minutes.

[0165] - Slide on the skin to evaluate the permeability index of the product. Then a group of evaluators evaluate the remaining amount of the recovered product.

[0166] - Conduct mechanical friction on the skin to evaluate the degree of flocculation. The product will form flocs.

[0167] The viscosities of these two emulsions are basically equal, about 12000 mPa·s, and the droplet size is less than 10 μm.

[0168] Table 3 shows the sensory experiences obtained from the emulsions prepared from the emulsifying compositions according to the present invention, and compares them with the sensory experiences obtained from the emulsions prepared using the reference emulsifying compositions.

[0169] The sensory properties of the emulsion according to the present invention are improved. The improvement criteria are: grindability, spreadability, greasiness, softness, brittleness, permeability, and flocculation degree.

[0170] [Table 3]

[0171]

Claims

1. An emulsifying composition for use in cosmetics and capable of obtaining an oil-in-water emulsion, comprising: a) from 40% to 95% of at least one cyclodextrin in solid particle form, said particles having a volume average size d(4,3) determined by laser granulometry, said volume average size being between 2 μm and 20 μm, the cyclodextrin particles having a volume size distribution determined by laser diffraction granulometry, the characteristic diameters d(10), d(50) and d(90) of said volume size distribution being: a’) a diameter d(10) less than or equal to 5.0 μm, and b’) a diameter d(50) less than or equal to 15.0 μm, and c’) a diameter d(90) less than or equal to 30.0 μm, and a volume size distribution determined by laser diffraction granulometry, said volume size distribution having a coefficient of variation less than or equal to 100%, b) and from 5% to 40% of at least one natural-source emulsifier selected from oil-in-water emulsifiers, said natural-source emulsifier having a hydrophilic-lipophilic balance value greater than or equal to 8 and being selected from mixtures of alkyl polyglycosides and fatty alcohols, said mixtures of alkyl polyglycosides and fatty alcohols being selected from: - myristyl alcohol and myristyl glucoside, - arachidyl alcohol, behenyl alcohol and arachidyl glucoside, - cetearyl alcohol and cetearyl glucoside, - cetearyl alcohol and coco glucoside, and - coco glucoside and coco alcohol.

2. The emulsifying composition according to claim 1, characterized in that the hydrophilic-lipophilic balance value of said at least one natural-source emulsifier is between 8 and 20.

3. The emulsifying composition according to claim 1, the average hydrophilic-lipophilic balance value of the entire emulsifying system of said composition being greater than or equal to 8.

4. The emulsifying composition according to claim 1, characterized in that the emulsifier / cyclodextrin ratio of the natural-source emulsifier present in said emulsifying composition is between 0.01:1 and 1:

1.

5. The emulsifying composition according to claim 1, characterized in that said cyclodextrin is selected from α-, β- and γ-cyclodextrins.

6. The emulsifying composition according to claim 1, further comprising: from 0% to 40% of at least one polyol.

7. A liquid emulsion, characterized in that it comprises at least one cyclodextrin in solid particle form, said particles having a volume average size d(4,3) between 2 μm and 20 μm, the cyclodextrin particles having a volume size distribution determined by laser diffraction granulometry, the characteristic diameters d(10), d(50) and d(90) of said volume size distribution being: a’) a diameter d(10) less than or equal to 5.0 μm, and b’) a diameter d(50) less than or equal to 15.0 μm, and c’) a diameter d(90) less than or equal to 30.0 μm, and a volume size distribution determined by laser diffraction granulometry, said volume size distribution having a coefficient of variation less than or equal to 100%, and at least one natural-source emulsifier from oil-in-water emulsifiers, the hydrophilic-lipophilic balance value of the natural-source emulsifier being greater than or equal to 8 and selected from the mixture of alkyl polyglycosides and fatty alcohols, the mixture of alkyl polyglycosides and fatty alcohols being selected from: - myristyl alcohol and myristyl glucoside, - arachidyl alcohol, behenyl alcohol and arachidyl glucoside, - cetearyl alcohol and cetearyl glucoside, - cetearyl alcohol and coco glucoside, and - coco glucoside and coco alcohol, and the ratio of emulsifier / cyclodextrin is between 0.01:1 and 1:

1.

8. The emulsion according to claim 7, wherein, the emulsion is such that the oil phase is dispersed in the water phase, and the average size of the dispersed oil-phase droplets is less than 30 μm.

9. The emulsion according to claim 7, the viscosity of the emulsion at 25 °C being greater than 3000 mPa·s.

10. A method for manufacturing a liquid emulsion, the method comprising the following steps: a) dispersing in the water phase an emulsifying composition comprising at least one cyclodextrin in solid particle form, the particles having a volume average size d(4,3) determined by laser granulometry, the volume average size being between 2 μm and 20 μm, the cyclodextrin particles having a volume size distribution determined by laser diffraction granulometry, the characteristic diameters d(10), d(50) and d(90) of the volume size distribution being: a’) the diameter d(10) is less than or equal to 5.0 μm, and b’) the diameter d(50) is less than or equal to 15.0 μm, and c’) the diameter d(90) is less than or equal to 30.0 μm, and a volume size distribution determined by laser diffraction granulometry, the coefficient of variation of the volume size distribution being less than or equal to 100%, and comprising at least one natural-source emulsifier from oil-in-water emulsifiers, the hydrophilic-lipophilic balance value of the natural-source emulsifier being greater than or equal to 8 and selected from the mixture of alkyl polyglycosides and fatty alcohols, the mixture of alkyl polyglycosides and fatty alcohols being selected from: - myristyl alcohol and myristyl glucoside, - arachidyl alcohol, behenyl alcohol and arachidyl glucoside, - cetearyl alcohol and cetearyl glucoside, - cetearyl alcohol and coco glucoside, and - coco glucoside and coco alcohol; the ratio of emulsifier / cyclodextrin is between 0.01:1 and 1:1, b) adding an oil phase to the mixture obtained in step a), the weight of the oil phase being 10% to 65% of the total weight of the composition, and after stirring to disperse the oil phase in the water phase, the average size of the dispersed oil-phase droplets is less than 30 μm.

11. Use of the emulsifying composition according to claim 1 in the preparation of a cosmetic emulsion for improving sensory properties, the improvement in sensory properties being such that the cosmetic emulsion has a softer texture, is powdery and reduces or eliminates flocculation.

12. The emulsifying composition according to claim 1 or the liquid emulsion according to claim 7 or the method according to claim 10 or the use according to claim 11, wherein the particles have a volume average size d(4,3) determined by laser granulometry, the volume average size being between 3 μm and 12 μm.

13. The emulsified composition according to claim 1, or the liquid emulsion according to claim 7, or the method according to claim 10, or the use according to claim 11, wherein the particles have a volume average size d(4,3) measured by laser particle size analysis, and the volume average size is between 4 μm and 8 μm.

14. The emulsified composition according to claim 1, wherein: a’) the diameter d(10) is less than or equal to 2.5 μm, and b’) the diameter d(50) is less than or equal to 10.0 μm, and c’) the diameter d(90) is less than or equal to 25.0 μm.

15. The emulsified composition according to claim 1, wherein the coefficient of variation of the volume size distribution is less than or equal to 90%.

16. The emulsified composition according to claim 1, wherein the coefficient of variation of the volume size distribution is less than or equal to 73%.

17. The emulsified composition according to claim 4, wherein the hydrophilic-lipophilic balance value of the emulsifier is between 9 and 16.

18. The emulsified composition according to claim 4, wherein the hydrophilic-lipophilic balance value of the emulsifier is between 11 and 14.

19. The emulsified composition according to claim 5, wherein the average hydrophilic-lipophilic balance value of the entire emulsification system of the composition is greater than or equal to 9.

20. The emulsified composition according to claim 1, or the liquid emulsion according to claim 7, or the method according to claim 10, wherein the emulsifier / cyclodextrin ratio of the emulsifier present in the emulsified composition is between 0.05:1 and 0.5:

1.

21. The emulsified composition according to claim 1, or the liquid emulsion according to claim 7, or the method according to claim 10, wherein the emulsifier / cyclodextrin ratio of the emulsifier present in the emulsified composition is between 0.10:1 and 0.35:

1.

22. The emulsified composition according to claim 1, or the liquid emulsion according to claim 7, or the method according to claim 10, wherein the emulsifier / cyclodextrin ratio of the emulsifier present in the emulsified composition is between 0.15:1 and 0.30:

1.

23. The emulsified composition according to claim 1, characterized in that the cyclodextrin is natural β-cyclodextrin.

24. The emulsion according to claim 7, or the method according to claim 10, wherein the liquid emulsion is an oil-in-water Pickering emulsion.

25. The emulsion according to claim 8, or the method according to claim 10, wherein the average size of the dispersed oil phase droplets is less than or equal to 10 μm.

26. The emulsion according to claim 7, wherein the viscosity of the emulsion at 25 °C is greater than 5000 mPa·s.

27. The emulsified composition according to claim 1, or the liquid emulsion according to claim 7, or the method according to claim 10, wherein the emulsifier is cetearyl alcohol and cetearyl glucoside.

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