Emulsified composition comprising water-in-oil emulsifier and cyclodextrin, and preparation and use thereof

Abstract

The present invention relates to a sensory emulsifying composition specially used for cosmetics, which can obtain an oil-in-water emulsion, wherein the emulsion comprises at least one cyclodextrin in the form of solid particles and at least one emulsifier of natural origin selected from water-in-oil emulsifiers, wherein the volume average size d(4,3) of the particles measured by a laser particle size analyzer is between 2 μm and 20 μm, preferably between 3 μm and 12 μm, and more preferably between 4 μm and 8 μm; and the hydrophilic-lipophilic balance value, i.e., HLB, of the emulsifier is less than 8.

Description

[0001] The present invention relates to an emulsified composition of plant origin, which can be used immediately and directly cold, and can be particularly applied to the field of cosmetics. The composition comprises at least one cyclodextrin in the form of solid particles and at least one natural emulsifier, and the volume average size d(4,3) of the particles measured by a laser particle size analyzer is less than or equal to 20 μm. The emulsified composition according to the present invention can be used as a cosmetic composition itself, and can also be used as a premix for preparing and stabilizing an emulsion. The emulsified composition is particularly easy to produce delicate oil-in-water (O / W) emulsions, and the emulsions have a variety of textures according to different skin types. The obtained composition has a soft, powdery texture even when the oil phase in the emulsion is high, and is easy to apply without causing flocculation.

[0002] An emulsion is a liquid (or liquid made into a material) dispersed in the form of fine droplets in another liquid that is immiscible with the first liquid. Emulsions appear uniform in appearance, but appear uneven when observed under a microscope. The liquid in the form of droplets is called the dispersed phase (or discontinuous phase), and the other liquid is called the dispersion medium (or continuous phase). Usually, emulsions consist of two phases (simple emulsions): a hydrophilic (water) phase and a lipophilic (oil) phase. Oil-in-water emulsions are called direct emulsions.

[0003] Emulsions are widely used in the cosmetics field. As cosmetics, they must meet consumers' demands for high efficacy, safety and pleasant sensory properties. In order to meet these sensory properties, the formulations of emulsions are becoming increasingly complex as they contain more and more functional or sensory ingredients brought by synthesis (usually from petrochemical products).

[0004] Most emulsion cosmetic compositions are known, usually simple emulsions, stabilized with surfactants. For example, document EP 0685227 proposes a complex sunscreen cosmetic composition system, which comprises an aqueous continuous phase, a protective system capable of filtering UV rays, a surfactant, an organic solvent (low alcohol and low polyol), and at least one polymer, especially a crosslinked copolymer (alkyl acrylate, vinyl acetate). Document FR 2858777 describes an oil-in-water emulsion, which comprises at least one oil (fatty acid, wax, butter, natural oil-vegetable oil, animal oil, marine oil, synthetic oil or mineral oil, hydrogenated oil and mixtures thereof), at least one surfactant (ethoxylated polyglycerol ester, alcohol ethoxylate), at least one cosurfactant and water.

[0005] However, the use of surfactants in topical or oral products for human or animal use can have undesirable consequences. The reason is that surfactants can damage cell membranes. Therefore, efforts are constantly being made to reduce the potentially harmful effects of surfactants, especially in the cosmetic field.

[0006] Furthermore, cosmetics must still meet the new expectations of today's consumers: natural raw materials and even ingredients must be natural products. In fact, consumers are now looking for cosmetics that mainly consist of natural ingredients or raw materials, with a minimum of chemical modification or grafts of synthetic or petrochemical origin.

[0007] Furthermore, one of the objects of the present invention is to provide a composition which can be dispersed in an aqueous phase, even by a "low temperature" method, and then an oil or fatty substance is added to form a stable emulsion. Such a composition makes it possible to eliminate the dependence on surfactants of petroleum origin and not biodegradable, in particular on glycol derivatives and ethoxylated derivatives. The composition according to the invention also makes it possible to produce Pickering type emulsions. This type of emulsion does not contain surfactants and is stabilized by colloidal particles, generally silica, which are placed at the interface between the continuous phase and the dispersed phase. According to the invention, these colloidal particles are organic particles consisting of inclusion complexes between at least one cyclodextrin and at least one fatty molecule. The particles are very suitable for the skin or the hair and do not damage the cell membranes.

[0008] This effect is particularly significant, since the prior art shows that when producing cosmetic emulsified compositions containing cyclodextrins, it is not possible to obtain an emulsion directly simply at low temperatures: before this, it was necessary to use surfactants of petroleum origin. It is particularly important to note that according to document EP 2 091 502 B1, an oil-in-water (O / W) emulsion comprises water, a fatty substance, a modified polysaccharide and cyclodextrins, the main feature of which is that it contains a surfactant with a molecular weight of less than 5000 g / mol and less than 2% by weight. It is therefore not known or clear whether it is possible to prepare an emulsified system containing cyclodextrins in such a way that a very fine and stable emulsion can be obtained without having to rely on surfactants of petroleum origin.

[0009] Furthermore, the main factor that attracts cosmetic consumers lies first of all in the sensory properties of the cosmetics, and the good effects are directly observed after use. Therefore, the challenge for cosmetics is to provide beneficial cosmetic effects while providing a pleasant user experience as much as possible before or during the use of the cosmetics. However, removing functional or sensory ingredients from petrochemical products and replacing them with natural ingredients or adding new natural ingredients or ingredients of natural origin may reduce the sensory properties of the products and more or less significantly affect the characteristics of the cosmetics, especially the sensory properties of the cosmetics appearance, formulation, use, and application characteristics on the skin or epidermis. Similarly, compositions that meet the natural standard may be difficult to apply, smooth or fit during use, and may also feel rough, brittle or even rough. These imperfect sensory experiences are not conducive to improving the quality or product image of cosmetics.

[0010] The applicant has developed a new type of emulsified composition, "Beauté by DS 146". This innovative emulsifying composition is the subject of the patent application FR1762841 which has not yet been published. This composition is a β-cyclodextrin "Beauté by The mixture of CD 102″ and a natural water-in-oil emulsifier (e.g., polyglyceryl-3 diisostearate) can optimally adjust the physicochemical and sensory properties of the emulsion, thereby obtaining a suitable and stable viscosity. By producing an emulsion, such as a cream, a sensory experience with obvious effects and good acceptance can be observed in the natural emulsified composition developed by the applicant, but it is not perfect. Compared with a preparation containing a petrochemical surfactant, a cream containing such a natural emulsified composition may be difficult to apply on certain skin types, has poor penetration, is easy to flocculate, and may have a non-soft and powdery uneven feel, or even feel greasy.

[0011] One of the objects of the present invention is therefore to provide an improved emulsified composition for cosmetic use which improves the organoleptic properties of the product compared to the emulsified composition described in application FR 1 762 841, in particular with regard to powdery effect, ease of application, softness to the touch, wrinkling during application, permeability of the composition and floccules.

[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, not only related to environmental protection and safety, but also related to the health rights and interests of consumers. For this reason, 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 ethylene oxide 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 that allows pharmacists to prepare the formulation very simply and with minimal effort, in particular by adding all the ingredients to the same mortar or reactor (known in English as "one pot"). In terms of specific operations, the emulsified composition of the present invention can be used according to a "low temperature process" and even at room temperature. "Low temperature process" means that the emulsified composition can be used directly at a temperature below 45°C, more preferably at a temperature below 35°C, and even more preferably dispersed in water at room temperature for direct use.

[0014] Another object of the present invention is to provide a composition that can be widely used in cosmetics, i.e. the composition is universal for final product applications: it follows that the composition according to the invention can be used in a variety of products, such as emulsions, creams, gels, lotions... In addition, the composition is non-irritating to the skin and is 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 by monovalent, divalent or trivalent salts. This criterion is very important because cosmetic products in general, especially those intended for topical application, are susceptible to changes in pH or pH (for example, the pH of the skin is weakly acidic and varies between 4 and 6). Therefore, an emulsified composition without any specific use restrictions in terms of pH presents a strong technical advantage of cosmetic compositions.

[0015] The main purpose of the present invention is to solve the complex technical problems posed by all these objectives, and specifically comprises an emulsified composition, preferably an emulsified composition for cosmetics, which is capable of obtaining an oil-in-water emulsion, comprising:

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

[0017] b) at least one natural emulsifier selected from water-in-oil emulsifiers, having a hydrophile-lipophile balance value of less than 8, most preferably less than or equal to 7.

[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 comprises at least one cyclodextrin in the form of solid particles, wherein the volume average size d(4,3) of the particles measured by a laser particle size analyzer 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 the present application, the term "cyclodextrin" means and includes any cyclodextrin commonly known to those skilled in the art, such as natural and unsubstituted cyclodextrins containing 6 to 12 glucose units covalently linked between carbon 1 and carbon 4, in particular α-, β- and γ-cyclodextrins containing 6, 7 and 8 glucose units, respectively.

[0024] The term also includes "cyclodextrin derivatives", i.e. molecules in which at least a portion of the OH hydroxyl groups have been converted into OR groups, wherein R generally represents an alkyl group. It is understood that cyclodextrin derivatives include in particular methylated cyclodextrins and ethylated cyclodextrins, but also cyclodextrins substituted with hydroxyalkyl groups, such as hydroxypropylated cyclodextrins and hydroxyethylated cyclodextrins.

[0025] According to the present invention, cyclodextrins are 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, ie the hydroxyl groups are not chemically substituted.

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

[0027] According to the present invention, cyclodextrin is present in solid particles, characterized in that the volume average size d(4,3) of the particles measured by a laser particle size analyzer 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 may be of any regular or irregular geometric shape and may be individual cyclodextrin crystals or agglomerates of cyclodextrin crystals connected by crystal bridges. The solid particles of cyclodextrin preferably have a regular geometric shape.

[0029] The volume average size is usually expressed as d(4,3) and is determined according to the volume size distribution of ISO 9276-2:2014, which can be measured by a laser diffraction particle size analyzer, for example using series of laser particle size analyzers, such as Malvern Mastersizer 2000 TM ″、″Mastersizer3000 TM ″、″Mastersizer 3000E TM "or The company's "Particula LA960" laser particle size analyzer. According to the guidelines of the ISO 13320:2009 standard, laser diffraction measurements can be performed by wet or dry methods. When using the wet method, it is recommended to use 2-propanol as the measuring liquid.

[0030] The volume size distribution of the cyclodextrin solid particles is preferably measured by a laser diffraction particle size analyzer, and its characteristic diameters d(10), d(50) and d(90) are:

[0031] a) a diameter d(10) less than or equal to 5.0 μm, preferably less than or equal to 2.5 μm; and / or

[0032] b) a diameter d(50) less than or equal to 15.0 μm, preferably less than or equal to 10.0 μm; and / or

[0033] c) The diameter d(90) is less than or equal to 30.0 μm, preferably less than or equal to 25.0 μm.

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

[0035] According to a preferred embodiment, the volume size distribution of the cyclodextrin solid particles is preferably measured by a laser diffraction particle size analyzer, and its characteristic diameters d(10), d(50) and d(90) are:

[0036] a) a diameter d(10) between 0.8 μm and 5.0 μm, preferably between 1.0 μm and 2.5 μm; and

[0037] b) a diameter d(50) between 5 μm and 15.0 μm, preferably between 7 μm and 10.0 μm; and

[0038] c) The diameter d(90) is between 15 μm and 30.0 μm, preferably between 20 μm and 25.0 μm.

[0039] Even more preferably, the cyclodextrin solid particles exhibit a volume size distribution measured by a laser diffraction particle size analyzer having a coefficient of variation of less than or equal to 100%, preferably less than or equal to 90%, more 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 mean size d(4,3) of the volume, also called the volume mean diameter.

[0040] According to the preferred embodiment, the cyclodextrin is in the form of solid particles, and the size distribution of the cyclodextrin is calculated by volume. The volume distribution can be measured by a laser diffraction particle size analyzer, 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, most 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%, most preferably less than or equal to 73%.

[0043] Due to the selected size, the cyclodextrin particles can improve the touch in particular by increasing softness. In addition, depending on the skin type, the use of the composition can significantly reduce scratchiness and linting during application, or even eliminate linting.

[0044] Water-in-oil emulsifier

[0045] In the present application, the term "naturally derived" water-in-oil emulsifier (i.e. W / O emulsifier) ​​refers to any emulsifier obtained from renewable resources (in particular extracted or secreted by plants, microorganisms or algae) and capable of producing a water-in-oil emulsion after physical, chemical or enzymatic modification.

[0046] After extensive testing and experimentation, the applicant has observed that the combination of cyclodextrin and an emulsifier has an exciting effect. The emulsifier is used to prepare an emulsion with a hydrophilic-lipophilic balance (HLB) value of less than 8. It not only does not hinder the direct formation of an emulsion (i.e., an oil-in-water emulsion), but also does not affect the stability of such an O / W emulsion. It can also be used as an effective stabilizer to make the emulsion more stable in time and temperature.

[0047] This is all the more exciting, since it is known that the effectiveness of an emulsifier is primarily related to its solubility in each of the two phases. The phase in which the emulsifier is most soluble forms the continuous phase of the emulsion. Therefore, water-soluble emulsifiers preferentially stabilize O / W oil-in-water emulsions. However, the emulsified composition according to the present invention can be directly used cold for the preparation of O / W emulsions, and the solubility of the emulsified composition in water is particularly low. According to a preferred embodiment, the solubility of cyclodextrin (such as β-cyclodextrin) at 25°C is only 1.8%.

[0048] Without being bound by theory, it appears that only a very small amount of a naturally derived W / O emulsifier is required to greatly promote the formation of inclusion complexes between cyclodextrin and certain specific molecules in the dispersed oil phase, and to be located at the interface of the oil and water phases in the form of solid or semi-liquid colloidal particles, which have physical and sensory properties that are very suitable for skin or hair and do not damage cell membranes.

[0049] In particular, the average HLB value of the entire emulsification system of the composition is less than 8, preferably less than or equal to 7. The average HLB value of the entire emulsification system of the composition is calculated by the weighted average of the HLB values ​​of each emulsifier, that is, the result obtained by weighted calculation of the mass fraction of the total mass of the emulsifier.

[0050] The hydrophile-lipophile balance (HLB) value of the naturally derived W / O emulsifier is less than 8, and the ratio of W / O emulsifier / cyclodextrin in the emulsified composition (weight / weight) is preferably between 0.01:1 and 1:1, more preferably between 0.05:1 and 0.5:1, still more preferably between 0.10:1 and 0.30:15, and most preferably between 0.15:1 and 0.30:1.

[0051] W / O emulsifiers of natural origin are preferably selected from the following products that meet the above-mentioned HLB conditions: non-ethoxylated fatty acid esters of polyols, especially selected from glycerol, ethylene glycol, sorbitol, anhydrous sorbitan, tetrahydrohexitols, such as isosorbide, mannitol, xylitol, erythritol, maltitol, sucrose, glucose, polydextrose, hydrogenated glucose syrup, dextrin and non-ethoxylated fatty acid esters of hydrolyzed starch.

[0052] The W / O emulsifier of natural origin is preferably selected to carry out natural biodegradation in the natural environment of hydration. These emulsifiers can be the non-ethoxylated fatty acid esters of polyols obtained by free fatty acids or obtained by oil or oil mixture through transesterification. The employed fatty acid comprises 8 to 22 carbon atoms, preferably comprises 10 to 18 carbon atoms, particularly preferably comprises 12 to 18 carbon atoms. This acid can be straight chain acid or branched acid, saturated acid or unsaturated acid, has one or more side hydroxyl functional groups. This oil can be saturated oil or unsaturated oil at room temperature, liquid or solid state, and can have hydroxyl functional group, and iodine value is preferably between 1 to 145, particularly preferably between 5 to 105.

[0053] The W / O emulsifier of natural origin can also be selected from products that are naturally biodegradable in hydrated natural media, especially those whose hydrophile-lipophile balance (HLB value) is between 1.5 and 6.0, preferably between 2.0 and 5.0, and most preferably between 3.0 and 5.0.

[0054] W / O emulsifiers of natural origin can also be chosen from glycerol fatty acid esters, in particular from glyceryl oleate, glyceryl monostearate and glyceryl isostearate, for example the following products: glyceryl laurate (HLB preferably 5.2), glyceryl oleate (HLB preferably 4), for example IMWITOR 948, glyceryl isostearate from Lubrizol Schercemol Schercemol GMIS (HLB preferably 3.5) and glyceryl monostearate from Sympatens-GMS (HLB preferably 3.5).

[0055] The source can also be selected from sorbitan or sorbitan fatty acid esters, in particular from sorbitan laurate, sorbitan monopalmitate, sorbitan oleate, sorbitan stearate and sorbitan isostearate, such as the sorbitan trioleate product Kosteran-O / 3 (HLB is preferably 1.8); sorbitan monooleate MONTANE 80VG or SPAN 80-LQ-(RB) or Kosteran-O / 1 (HLB is preferably 4.3); sorbitan isostearate Kosteran-I / 1 (HLB is preferably 4.3), sorbitan monostearate Kosteran-S / 1 (HLB is preferably 4.7); sorbitan monopalmitate (HLB is preferably 6.6).

[0056] The source may also be selected from sucrose fatty acid esters, such as Sisterna's sucrose distearate SP60-C, Sisterna's sucrose polystearate SP10-C, sucrose cocoate (HLB preferably 6).

[0057] The W / O emulsifier of natural origin can be chosen in particular from polyglycerol fatty acid esters, preferably from fatty acid esters resulting from the reaction of polyglycerol, which fatty acid esters contain 2 to 12 units of glycerol, more preferably 3 to 6 units of glycerol, and reacted with at least one partially hydrogenated or non-hydrogenated vegetable oil having an iodine value between 1 and 15, especially with a non-hydrogenated vegetable oil having an iodine value between 5 and 10. The sources can be in particular polyglycerol oleate, polyglycerol stearate, polyglycerol isostearate and polyglycerol ricinoleate, in particular the following products: polyglycerol-4 isostearate with an HLB of preferably 3 (for example HYDRIOR PGI), polyglyceryl-10 pentaoleate (e.g. DECAGLYN 5-OV) with an HLB preferably of 3.5, polyglyceryl-6 polyricinoleate (e.g. HEXAGLYN PR-15), polyglyceryl-2 sesquiisostearate (e.g. Hostcerin DGI from Clariant and Glucerin from Evonik Dr. Straetmans) with an HLB preferably of about 4. GO), polyglyceryl-3 ricinoleate with an HLB preferably of 3.5, polyglyceryl-3 polyricinoleate with an HLB preferably of 4 (e.g. IMWITOR 600), polyglyceryl-3 polyricinoleate with an HLB preferably of about 4 (e.g. PGPR), polyglycerol-2 sesquioleate with an HLB of preferably 4 (e.g., from Evonik Dr. Straetmans GmbH GO soft), polyglyceryl-2 diisostearate (e.g., from ResPharma PG20), polyglyceryl-3 diisostearate with an HLB of preferably 5.5 (e.g. Diisostearique CG, from BASF TGI, from IOIOleo GmbH PG3 DIS, Cithrol from Croda TM PG32IS, DUB ISO G3 from Stéarinerie Dubois, 3-1-S, Jolee 7245 from Oléon and MASSOCARE PG3D from Masso), polyglyceryl-3 oleate with an HLB preferably of 6.2 (e.g. I-MUL PGO 31 from Ivanhoe Industries), polyglyceryl-3 monostearate with an HLB preferably of 7.2, polyglyceryl-2 dimerstearate (e.g. Dehymuls PGPH from Cognis), polyglyceryl-2 diisostearate (e.g. Emulpharma PG20 from Respharma) and polyglyceryl-3 cocoate (e.g. Ecotech).

[0058] More preferred esters are obtained by reacting polyglyceryl-3 with isostearic acid (INCI name: polyglyceryl-3 diisostearate), the HLB value of which is preferably equal to 5.5.

[0059] W / O emulsifiers of natural origin may consist of ester mixtures, in particular mixtures of polyglycerol fatty acid esters, sorbitan fatty acid esters or glucose esters, in particular mixtures such as the product Nikkomulse WO-NS from NikkoChemicals (polyglyceryl-6 polyricinoleate, polyglyceryl-2 isostearate, disteardimonium hectorite), TegoCare LTP from Evonik (sorbitan laurate, polyglyceryl-4 laurate, dilauryl citrate), Sympatens-W / 4500 (sorbitan oleate, polyglyceryl-3 polyricinoleate), Sympatens-O / 2500G (sorbitan stearate, methyl glucose sesquistearate), Dr. Straetmans' muls WO (polyglyceryl-3 polyricinoleate, sorbitan sesquioleate, cetyl ricinoleate, glyceryl caprate, beeswax, magnesium stearate, aluminum stearate), Natura-Tec's Ecomuls 2 in 1 (glyceryl monooleate, polyglyceryl-3 polyricinoleate, olive oil unsaponifiables), Alchemy's HIPEgel Olea (glycerin, isopropyl palmitate, water, sucrose stearate, sucrose laurate).

[0060] Effect of Cyclodextrin Particle Size Selection

[0061] with an emulsifying composition comprising cyclodextrins having a volume mean size greater than or equal to 90 μm (for example the emulsifying composition "Beauté by DS 146″), the emulsified composition according to the present invention can easily obtain an emulsion that is easy to disperse, making the emulsion more powdery, softer to the touch, less brittle, more permeable on keratin materials, and almost non-flocculating. Optionally, according to the different proportions used, the emulsified composition according to the present invention can also obtain interesting sensory effects, such as a special texture or a fresh feeling.

[0062] The above advantages of the emulsified composition result from the combination of the two compounds used, which work together to ensure that the emulsion has stability and good organoleptic properties. Whichever mixing ratio of the compounds is chosen, very satisfactory results are obtained, but even more convincing results are obtained if they are mixed in a more precise ratio.

[0063] In particular, before emulsification, the various components of the emulsified 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 (premix in English), which can be added to any phase of the emulsion in which the premix is ​​to be used. The present invention allows the compounds described in the two embodiments to be the same, thereby increasing practicality and simplifying operation. For reference, the applicant has commercialized an emulsified composition in the form of a premix outside the scope of the present invention, under the trade name "Beauté by DS146″, which contains β-cyclodextrin″Beauté by The volume average size of CD 102″ is approximately equal to 95 μm as measured by a dry laser particle size analyzer.

[0064] In particular, the emulsified composition according to the invention has the following particular advantages: the raw materials are natural and can be used according to the "low temperature process" method (i.e. carried out at room temperature). The composition according to the invention, in particular the composition for cosmetics, is insensitive to slight changes in the pH value or salinity of the medium, is non-irritating and is not likely to cause allergies, in particular skin allergies. In addition, the composition according to the invention can be used to produce any type of emulsion, in particular Pickering type emulsion, and is therefore suitable for a variety of uses: creams, emulsions, essences, lotions, etc.

[0065] water

[0066] The emulsified composition may contain water in a so-called "constituent or bound" form and / or in a so-called "free" form. Constituent or bound water consists of water molecules contained in the crystal structure of the cyclodextrin and / or polyol powder and water molecules adsorbed on the surface of the powder by physical hydration equilibrium. Free water consists of water molecules that can move freely between the cyclodextrin and / or polyol powder. This free water can in particular suspend the cyclodextrin and / or polyol powder.

[0067] According to one embodiment, the emulsified composition comprises constituted or bound water, the content of which accounts for 1% to 25% of the total weight of the emulsified composition. The content of constituted or bound water is preferably between 2% and 15%, and most preferably between 3% and 10%.

[0068] According to one embodiment, the emulsified composition may contain free water, the content of which is less than or equal to 50% of the total weight of the emulsified composition. The free water content 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%.

[0069] Polyols

[0070] According to one embodiment, the emulsified composition further comprises at least one polyol.

[0071] The polyols described in the present application are known polyols, in particular maltitol, mannitol, xylitol, erythritol, sorbitol, glycerol, preferably glycerol and sorbitol. The polyols are preferably in the form of crystals or powders.

[0072] Therefore, the present invention relates to an emulsified composition, in particular an emulsified composition for cosmetics and capable of obtaining an oil-in-water (O / W) emulsion, the oil-in-water emulsion comprising or consisting of:

[0073] 1) at least one cyclodextrin in the form of solid particles accounting for 40% to 95% of the total weight of the composition, wherein the particles have a volume average size d(4,3) of between 2 μm and 20 μm, preferably between 3 μm and 12 μm, and more preferably between 4 μm and 8 μm, as measured by a laser particle size analyzer;

[0074] 2) 5% to 40% by weight of the total composition of at least one natural emulsifier selected from water-in-oil emulsifiers, having an HLB value of less than 8, preferably less than or equal to 7; and

[0075] 3) 0% to 40% by weight of at least one polyol based on the total weight of the composition.

[0076] The emulsified composition according to the present invention preferably comprises, or preferably consists of:

[0077] 1) at least one cyclodextrin in the form of solid particles accounting for 45% to 85% of the total weight of the composition, wherein the particles have a volume average size d(4,3) of between 2 μm and 20 μm, preferably between 3 μm and 12 μm, and more preferably between 4 μm and 8 μm, as measured by a laser particle size analyzer;

[0078] 2) 5% to 30% by weight of the total composition of at least one natural emulsifier selected from water-in-oil emulsifiers, having an HLB value of less than 8, preferably less than or equal to 7; and

[0079] 3) 10 to 40% by weight of at least one polyol based on the total weight of the composition.

[0080] The composition according to the present invention most preferably comprises, or most preferably consists of:

[0081] 1) at least one cyclodextrin in the form of solid particles accounting for 40% to 80% of the total weight of the composition, wherein the particles have a volume average size d(4,3) of between 2 μm and 20 μm, preferably between 3 μm and 12 μm, and more preferably between 4 μm and 8 μm, as measured by a laser particle size analyzer;

[0082] 2) 10% to 20% by weight of the total composition of at least one natural emulsifier selected from water-in-oil emulsifiers, having an HLB value of less than 8, preferably less than or equal to 7; and

[0083] 3) 10% to 30% by weight of at least one polyol based on the total weight of the composition.

[0084] In the three embodiments of the above emulsified composition, a water-in-oil emulsifier with an HLB value of less than 8 is preferred, and the emulsifier is a non-ethoxylated fatty ester of a polyol with an HLB value of less than 8.

[0085] Using an emulsion of the emulsified composition, preferably an emulsion of the Pickering type

[0086] The emulsifying composition according to the invention makes it possible in particular to produce emulsions of the Pickering type which can be stabilized by organic particles suitable for the skin or hair. Replacing the surfactant with an emulsifying system consisting of solid particles combined with a fatty substance gives so-called "Pickering" emulsions.

[0087] The emulsified composition according to the invention may also contain other products capable of forming or stabilizing Pickering emulsions, such as silicon dioxide in the form of calcium or aluminum salts and starch octenylsuccinate.

[0088] 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, characterized in that it contains at least one cyclodextrin in the form of solid particles, wherein the particles have a volume average size d(4,3) of between 2 μm and 20 μm, preferably between 3 μm and 12 μm, and more preferably between 4 μm and 8 μm, as measured by a laser particle size analyzer; and

[0089] At least one natural emulsifier, wherein the emulsifier / cyclodextrin (weight / weight) ratio is between 0.01:1 and 1:1, preferably between 0.15:1 and 0.30:1. The HLB value of the natural emulsifier is less than 8, preferably less than or equal to 7.

[0090] The emulsions used for the emulsified compositions according to the invention, in particular the emulsions from Pickering, additionally comprise an aqueous phase consisting of water.

[0091] 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 60% to 92%, and most preferably 65% ​​to 90%. According to this embodiment, the emulsion is ready to use, so the user can use it without adding additional water.

[0092] According to the "water-poor" embodiment, the water content in the emulsion is 2% to 50% of the total weight of the emulsion, preferably 5% to 35%, and most preferably 10% to 40%. The emulsion according to this embodiment has the advantage that the mass of the container, such as a flask, a flask or a mortar, is reduced by reducing the mass of water in the emulsion. This not only reduces the transportation cost, but also reduces the amount of waste gas emitted due to transportation. The user may need to add water during use to ensure that this embodiment is implemented correctly.

[0093] The emulsion used in the emulsified composition according to the present invention, in particular the Pickering O / W emulsion, may also contain an oil phase, which may be liquid (e.g., vegetable oil) or solid (e.g., wax) at room temperature (25° C.). The liquid oil phase may be a mineral oil, an animal oil, a vegetable oil, or a synthetic oil, and may be composed of a hydrocarbon oil or even a silicone oil. The term "hydrocarbon-based oil" refers to an oil mainly formed by carbon atoms and hydrogen atoms, and may also be oxygen atoms, nitrogen atoms, or even composed of them, and may contain alcohols, esters, ethers, carboxylic acids, or amino groups and / or amides. The oil content of the final O / W emulsion is preferably between 10% and 65%, more preferably between 20% and 55%.

[0094] The emulsion used in the emulsified composition according to the present invention may contain one or more oils, preferably at least one non-volatile liquid oil. The term "non-volatile liquid oil" refers to an oil that can remain on the skin for at least one hour at room temperature and atmospheric pressure.

[0095] The liquid oil phase may also contain one or more non-volatile oils that lubricate the skin. For example, fatty esters such as cetearyl isononanoate, isotridecyl isononanoate, isostearyl isostearate, isopropyl isostearate, isopropyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, isononyl isononyl, 2-ethylhexyl palmitate, 2-hexyldecyl laurate, 2-octyldecyl palmitate, 2-octyldodecyl myristate or lactate, 2-diethylhexyl succinate, diisostearyl malate, quince, tricaprylyl, caprylic / capric triglyceride. Esters, 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, tsubaki oil, cashew oil, argan oil, soybean oil, grape seed oil, sesame oil, corn oil, wheat germ oil, rapeseed oil, sunflower seed oil, cottonseed oil, jojoba oil, peanut oil, olive oil and mixtures thereof), vegetable fats (such as shea butter), camellia butter.

[0096] These oils may be hydrocarbon oils or silicone oils, for example paraffin oil, squalane oil, petrolatum, dimethicone and mixtures thereof.

[0097] The liquid oil phase may also optionally contain a variety of volatile oils. Volatile oils refer to oils that 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 greasy feeling.

[0098] The emulsion composition used in the emulsion composition according to the present invention, in particular the Pickering O / W emulsion, preferably contains only oils of renewable origin, in particular oils of vegetable origin or butter, preferably refined oils. These oils and butters are very consistent with the emulsification system used in the emulsion composition, and the subject of the present invention is the emulsion composition, because using the emulsion composition, a very stable emulsion can be obtained, and the emulsion is bright and white, and the viscosity is adjustable. The emulsion composition of the present invention can prepare an oil-in-water emulsion with a very high oil content. The oil-rich O / W emulsion is usually difficult to gradually stabilize over time with the help of conventional emulsifiers. The oil content of the O / W emulsion used in the emulsion 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 oils of vegetable origin, such as sunflower oil and isopropyl palmitate, can especially obtain stable emulsions without having to cause emulsification or phase shift.

[0099] According to the present invention, the emulsion of the emulsified composition used may contain a rheological agent, which may be, in particular, an aqueous phase thickener, gelling agent or suspending agent, such as gum arabic, konjac gum, guar gum or derivatives thereof derived from plant gums; algae gum extracted from algae, such as alginate gel or carrageenan; microbial gum 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 starch, in particular acetylated starch, carboxymethylated starch, octenyl succinate starch or hydroxypropylated starch; synthetic polymers, such as polyacrylates or carbomer gum.

[0100] According to the present invention, the emulsifier used in the emulsified composition preferably contains a rheological agent, which is selected from natural polysaccharides produced by plants or fermentation, and the natural polysaccharides can be modified. Xanthan gum and its derivatives can especially obtain oil-in-water emulsions with extremely fine droplet sizes, even when the emulsion content is less than 1% of the total weight of the emulsion.

[0101] The emulsion of the emulsified composition according to claim is characterized in that the emulsion is preferably in the form of an oil phase dispersed in an aqueous phase, and the average size of the dispersed oil phase droplets is less than 30 μm, preferably less than or equal to 10 μm.

[0102] The small droplet size can reduce the flocculation rate of the emulsion, thereby reducing the phase separation rate, thereby improving the stability of the emulsion. The average droplet size is determined by a large number of parameters, characterized in that the size is controllable and can be varied according to different formulations of the emulsified composition.

[0103] The average droplet size can be measured using a LEICA DMLS optical microscope at 10x magnification, and then at least ten droplets are counted and the average is calculated.

[0104] The emulsion used in the emulsified composition according to the present invention may further comprise a preservative selected from the group consisting of benzyl alcohol, dehydroacetic acid and a mixture thereof.

[0105] The viscosity of the emulsion used in the emulsified composition according to the present invention is preferably higher than 3000 mPa·s at 25°C, and more preferably higher 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 is in contact with the product sample. The resistance to the product during the rotational motion for one minute is recorded, and the result is converted into "milliPascal·seconds", usually recorded as mPa·s. The viscosity is measured three times for each sample, and the arithmetic mean of the three measurements is retained.

[0106] In order to characterize the organoleptic properties of the emulsion composition according to the invention, we used sensory indicators and a corresponding five-step sensory evaluation protocol. These five steps correspond to the different use stages of the skin care product: appearance, handling, use, application after 1 minute and application after 2 minutes. In these five stages, a panel of ten assessors evaluated several sensory indicators in order to compare the emulsion according to the invention with the emulsion according to the patent application FR1762841 filed by the applicant. The difference between the emulsion according to the invention and the emulsion according to the patent FR1762841 in terms of sensory properties is: degree of crushing, degree of application, degree of oiliness, softness, degree of cracking, permeability and degree of flocculation. The emulsion according to the invention has a texture that is easier to apply and penetrate, a more oily texture, but it feels more powdery, softer and more flexible. In addition, the emulsion has less flocculation or even no flocculation, depending on the different skin types.

[0107] In addition, the emulsified composition according to the present invention is more conducive to the production of an oil-in-water O / W emulsion with high stability, fine texture, soft touch, freshness and smoothness, even for an emulsion with a high content of dispersed oil phase. Therefore, an emulsion with good emollient effect and good moisturizing of the skin surface can be obtained.

[0108] The emulsified composition is particularly easy to produce fine O / W emulsions with various textures, close to the skin, dry touch, fresh and silky, and even high oil phase content.

[0109] Method for producing an emulsion using an emulsified composition

[0110] Another object of the present invention is a method for manufacturing an oil-in-water emulsion, preferably of the Pickering type, in particular an emulsion for cosmetic use, comprising the following steps:

[0111] a) dispersing an emulsified composition in an aqueous phase, the emulsified composition comprising at least one cyclodextrin in the form of solid particles, the volume average size d(4,3) of the particles measured by a laser particle size analyzer being between 2 and 20 μm, preferably between 3 and 12 μm, more preferably between 4 and 8 μm; and comprising at least one natural source emulsifier from the oil-in-water type emulsifier, the HLB of which is less than 8, preferably less than or equal to 7, and the ratio of emulsifier / cyclodextrin being between 0.01:1 and 1:1, preferably between 0.15:1 and 0.30:1;

[0112] b) adding the oil phase to the mixture obtained in step a), and stirring to disperse the oil phase in the aqueous phase, the weight of the oil phase accounting for 10% to 65% of the total weight of the composition, and the average size of the oil phase droplets is less than or equal to 30 μm, preferably less than or equal to 10 μm.

[0113] According to a variant, the method for preparing an oil-in-water emulsion according to the invention, preferably a Pickering emulsion, in particular an emulsion for cosmetics, comprises the following steps:

[0114] a) dispersing an emulsified composition in an oil phase, wherein the emulsified composition comprises at least one cyclodextrin in the form of solid particles, wherein the volume average size d(4,3) of the particles measured by a laser particle size analyzer is between 2 and 20 μm, preferably between 3 and 12 μm, and more preferably between 4 and 8 μm;

[0115] and comprising at least one emulsifier of natural origin from the group of water-in-oil emulsifiers, whose HLB is less than 8, and the HLB value of the non-ethoxylated fatty esters of polyols is preferably less than 8, the ratio of emulsifier / cyclodextrin being between 0.01:1 and 1:1, preferably between 0.15:1 and 0.30:1, and the weight of the oil phase being preferably between 10% and 65%, more preferably between 20% and 55% of the final weight of the emulsion;

[0116] b) adding the oil phase to the mixture obtained in step a), and stirring to disperse the oil phase in the water phase, wherein the average size of the oil phase droplets is less than or equal to 30 μm, preferably less than or equal to 10 μm.

[0117] use

[0118] Finally, the present invention also has the following uses:

[0119] - at least one cyclodextrin in the form of solid particles, the particles having a volume average size d(4,3) of between 2 μm and 20 μm, preferably between 3 μm and 12 μm, more preferably between 4 μm and 8 μm, as measured by a laser particle size analyzer; and

[0120] - at least one emulsifier of natural origin selected from water-in-oil emulsifiers, which has a hydrophilic-lipophilic balance value of less than 8, preferably less than or equal to 7 in the cosmetic liquid emulsion, so as to make the emulsion softer and more waxy to the touch, easier to apply when using the emulsion, and reduce or eliminate flocculation. Example

[0121] The present invention may be better understood by reference to the following non-limiting exemplary embodiments.

[0122] Example 1: Emulsion

[0123] An oil-in-water emulsion produced according to the present invention was compared to a "reference" oil-in-water emulsion produced outside the scope of the present invention, both prepared according to the composition of Table 1.

[0124] [ Table 1 ]

[0125]

[0126] The reference emulsion was prepared by using the emulsion described by the applicant under the name "Beauté by CD102" is obtained by β-cyclodextrin sold under the trade name. Using the same β-cyclodextrin previously dried, the volume average size d(4,3) of which is less than 20 μm, the emulsion of the present invention can be obtained: the β-cyclodextrin obtained is called "ultrafine particles". Table 2 lists the particle size characteristics of these two β-cyclodextrins.

[0127] [ Table 2 ]

[0128]

[0129] The specific scheme for preparing the emulsion is as follows. First, the thickener (xanthan gum in this case) is dispersed in water at 40°C while stirring with a deflocculating blade at a speed of 500 revolutions per minute. β-cyclodextrin is mixed with sorbitol and polyglyceryl-3 diisostearate respectively. Then, the mixture is added to the water containing the thickener while stirring at a speed of 1000 revolutions per minute to prepare the aqueous phase.

[0130] The amount of β-cyclodextrin was set at 2.5% by weight for both emulsions.

[0131] The oil phase consisting of sunflower oil was heated to 40°C.

[0132] The oil phase was then emulsified in the water phase at 40°C while stirring at 3000 rpm for 20 minutes.

[0133] Afterwards, the mixture was cooled at room temperature (20°C) and finally a phenoxyethanol-based preservative was added.

[0134] Each emulsion was characterized for physicochemical properties, droplet viscosity and average size, and sensory properties such as flow, slip, spread, greasiness, softness, brittleness, penetration, crumble, and flocculation were measured.

[0135] The viscosity is measured using a Brookfield DV-II+Pro viscometer. A fixed-size impeller (refer to the equipment instructions, the impeller of the SP2 to SP7 model is used according to the viscosity level) rotates at a speed of 20 revolutions per minute and contacts the prepared sample. The resistance to the product during the rotational movement is recorded for one minute and the result is converted to millipascal seconds. The viscosity is measured three times for each sample, and the arithmetic mean of the three measurements is retained.

[0136] The average droplet size was measured using an optical microscope at 10× magnification, and at least ten typical droplets were counted and the arithmetic mean was calculated using a LEICA DMLS microscope.

[0137] The sensory profiles were evaluated by a panel of ten experts in cosmetic texture analysis.

[0138] When applying the product, two parameters are evaluated: 50μL to 100μL of the product to be tested is placed on the hand and applied 10 circles, and the product is inspected under a light fixture.

[0139] - The crushing index was assessed during the second and fifth application cycles. The fingers glided smoothly over the skin. It was observed that the product turned into a powdery substance on the skin.

[0140] -Put 50μL to 100μL of the product to be tested on the hand and apply it 10 times, inspecting the product under a light fixture to assess the spreadability. Spreadability is also important because there is little resistance when applying it between the 5th and 10th circles on the hand.

[0141] After 10 cycles of application, subsequent indicators were evaluated.

[0142] For the next two indicators, 50 μL to 100 μL of product should be applied to the skin and examined under a light after 1 minute.

[0143] - Glide over skin to assess softness indicators, it should feel dry and smooth to the touch.

[0144] -Assess the snap index by rubbing the dough back and forth between your thumb and index finger. You should feel a sticky sensation and hear a snapping sound.

[0145] For the next two indicators, 50μL to 100μL of product should be applied to the skin and then checked under a light after 2 minutes.

[0146] - Glide on the skin to evaluate the product's penetration indicators. The recovered product is then evaluated by a panel of assessors for the amount of residue left.

[0147] - Evaluate the flocculation by mechanical rubbing on the skin. The product will form flocculation.

[0148] [ Table 3 ]

[0149]

[0150] The improvement of the sensory properties of the emulsion according to the present invention is carried out according to the following standards: fluidity, crushing degree, coating property, greasiness, softness, brittleness, penetration and flocculation degree.

[0151] Example 2: Sunscreen

[0152] According to the following operating steps, β-cyclodextrin with an average diameter of 200 μm (Beauté by Example 1) was used. The sensory properties of the sunscreens were compared using β-cyclodextrin (ultrafine microparticle β-cyclodextrin of Example 1) or β-cyclodextrin with a volume average size of 11.43 μm.

[0153] First, prepare phase A1 according to the composition in Table 4: Sunsphere powder was dispersed in water and Cetiol C5, then heated to 55°C while being stirred by a rotor stator at 2000 rpm for 15 minutes.

[0154] [ Table 4 ]

[0155]

[0156]

[0157] In addition, all ingredients in a measuring cup were weighed to prepare phase A2, which was then added to phase A1 and stirred at 2000 rpm for 15 minutes using a rotor stator. Phase A1+A2 was then stirred and stored at 70°C.

[0158] [ Table 5 ]

[0159]

[0160] Then, according to the composition of Table 6, phase B1 was prepared, heated to 70° C. and magnetically stirred for 10 minutes.

[0161] [ Table 6 ]

[0162]

[0163]

[0164] Phase B1 was maintained at 70° C. and stirred, and phase B2 prepared separately and composed according to the composition in Table 7 was added, and then the mixture was stirred for 10 minutes, and then phase B1+B2 was emulsified into phase A.

[0165] [ Table 7 ]

[0166]

[0167] To emulsify phase B1+B2 in phase A, first inject all phase B1+B2 into phase A at 55°C while stirring with a rotor stator at 2500 rpm, then let stand for 5 minutes at 55°C, and then soak in cold water for 10 minutes. Reduce the speed to 1200 rpm and continue stirring until the emulsion temperature in the cold water drops to room temperature.

[0168] Then add phase C and use phase D for coloring.

[0169] [ Table 8 ]

[0170]

[0171]

[0172] Thus, a colorful, fragrant cream is obtained. When the cream is applied to the skin, it feels comfortable, but it cracks slightly when applied.

[0173] Then, a sunscreen was prepared according to the above scheme, using the "ultrafine particle" β-cyclodextrin of Example 1 instead of "Beauté by CD102". Apply the cream to the skin: no more flocculation after application, the cream is more suitable. Slight brittleness still occurs at the end of the cream penetration, but significantly less than in the formula containing β-cyclodextrin"Beauté by CD102″ reference cream.

Claims

1. An emulsified composition, which can obtain a liquid oil-in-water emulsion, comprising: a) at least one β-cyclodextrin in the form of solid particles, wherein the volume average size d(4,3) of the particles measured by a laser particle size analyzer is between 8 μm and 12 μm, and b) at least one natural emulsifier selected from polyglyceryl-3 diisostearate, c) at least one polyol.

2. The emulsified composition according to claim 1, characterized in that The volume size distribution of the cyclodextrin particles is measured by a laser diffraction particle size analyzer, and the characteristic diameters d(10), d(50) and d(90) are: a) diameter d(10) less than or equal to 5.0 μm; and / or b) a diameter d(50) less than or equal to 15.0 μm; and / or c) The diameter d(90) is less than or equal to 30.0 μm.

3. The emulsified composition according to claim 1, characterized in that The cyclodextrin solid particles are distributed in volume size, the distribution is measured by a laser diffraction particle size analyzer, and the coefficient of variation is less than or equal to 100%.

4. The emulsified composition according to claim 1, wherein the hydrophile-lipophile balance (HLB) of the naturally derived water-in-oil emulsifier is between 1.5 and 6.

0. The emulsified composition according to claim 1 , wherein the average HLB value of the entire emulsified system of the composition is less than 8.

6. The emulsified composition according to claim 1, characterized in that The natural emulsifier has an emulsifier / cyclodextrin ratio between 0.01:1 and 1:

1.

7. The emulsified composition according to claim 1, comprising: 1) 40% to 95% of at least one solid particle form of β-cyclodextrin, wherein the particles have a volume average size d(4,3) between 8 μm and 12 μm as measured by a laser particle size analyzer; 2) 5% to 40% of at least one polyglyceryl-3 diisostearate; and 3) 0% to 40% of at least one polyol.

8. An emulsion, characterized in that It comprises at least one β-cyclodextrin in the form of solid particles, wherein the volume average size d(4,3) of the particles is between 8 μm and 12 μm; and it comprises at least one natural emulsifier selected from polyglyceryl-3 diisostearate, wherein the hydrophilic-lipophilic balance value of the natural emulsifier is less than 8, and the ratio of emulsifier / cyclodextrin is between 0.01:1 and 1:

1.

9. The emulsion according to claim 8, characterized in that The emulsion is in the form of an oil phase dispersed in a water phase, and the average size of the dispersed oil phase droplets is less than 30 μm.

10. The emulsion according to claim 8, having a viscosity greater than 3000 mPa·s at 25°C.

11. A method for producing a liquid emulsion, the method comprising the following steps: a) dispersing an emulsified composition in an aqueous phase, wherein the emulsified composition comprises at least one solid particle form of β-cyclodextrin, wherein the volume average size d(4,3) of the particles measured by a laser particle size analyzer is between 8 and 12 μm; and comprises at least one natural emulsifier selected from polyglyceryl-3 diisostearate, wherein the hydrophilic-lipophilic balance value of the natural emulsifier is less than 8; and 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), and stirring to disperse the oil phase in the water phase, wherein the weight of the oil phase accounts for 10% to 65% of the total weight of the composition, and the average size of the oil phase droplets is less than or equal to 30 μm.

12. Use of at least one solid particle form of β-cyclodextrin and at least one naturally derived emulsifier selected from polyglycerol-3 diisostearate in the preparation of a cosmetic liquid emulsion, wherein the volume average size d(4,3) of the particles measured by a laser particle size analyzer is between 8 μm and 12 μm; and the hydrophile-lipophile balance value of the naturally derived emulsifier is less than 8, so that the emulsion feels softer and more powdery, is easier to apply when using the emulsion, and reduces or eliminates flocculation.

13. The emulsified composition according to claim 1 or 7, or the emulsion according to claim 8, or the method according to claim 11, or the use according to claim 12, characterized in that The volume average size d(4,3) of the cyclodextrin particles measured by a laser particle size analyzer is between 4 and 8 μm.

14. The emulsified composition according to claim 1 or 7, or the emulsion according to claim 8, or the method according to claim 11 or the use according to claim 12, characterized in that The at least one natural emulsifier has a hydrophile-lipophile balance value of less than or equal to 7.

15. The emulsified composition according to claim 2, characterized in that The diameter d(10) is less than or equal to 2.5 μm.

16. The emulsified composition according to claim 2, characterized in that The diameter d(50) is less than or equal to 10.0 μm.

17. The emulsified composition according to claim 2, characterized in that The diameter d(90) is less than or equal to 25.0 μm.

18. The emulsified composition according to claim 3, characterized in that: The coefficient of variation of the volume particle size distribution is less than or equal to 90%.

19. The emulsified composition according to claim 3, characterized in that The coefficient of variation of the volume particle size distribution is less than or equal to 73%.

20. The emulsified composition according to claim 4, wherein the hydrophile-lipophile balance (HLB) of the naturally derived water-in-oil emulsifier is between 2.0 and 5.

0.

21. The emulsified composition according to claim 4, wherein the hydrophile-lipophile balance (HLB) of the naturally derived water-in-oil emulsifier is between 3.0 and 5.

0.

22. The emulsified composition according to claim 5, wherein the average HLB value of the entire emulsified system of the composition is less than or equal to 7.

23. The emulsified composition according to claim 6, characterized in that The natural emulsifier has an emulsifier / cyclodextrin ratio between 0.05:1 and 0.5:

1.

24. The emulsified composition according to claim 6, characterized in that The natural emulsifier has an emulsifier / cyclodextrin ratio between 0.10:1 and 0.35:

1.

25. The emulsified composition according to claim 6, or the emulsion according to claim 7, or the method according to claim 11, characterized in that The natural emulsifier has an emulsifier / cyclodextrin ratio between 0.15:1 and 0.30:

1.

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

27. The emulsion according to claim 9 or the method according to claim 11, characterized in that The average size of the dispersed oil phase droplets is less than or equal to 10 μm.

28. The emulsion according to claim 10, characterized in that The viscosity at 25°C is greater than 5000 mPa·s.

29. The emulsion according to claim 8, or the method according to claim 11, characterized in that The emulsion is a Pickering oil-in-water emulsion.

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