Mixtures containing functional agents and related methods of manufacture

Abstract

The present invention relates to a mixture (1) comprising at least 50% by weight of a functional agent, also comprising a waxy matrix (3) having the functional agent dispersed therein, the mixture (1) being solid at room temperature and intended to be dispersed in a cosmetic and / or dermatological composition by fluidization and / or solubilization to incorporate the functional agent into the cosmetic and / or dermatological composition, the functional agent being formed from surface-treated solid particles (2) resulting in a reduced absorption capacity of the waxy matrix (3) by the treated solid particles (2) compared to untreated solid particles of the same nature. The present invention also relates to the formulation of cosmetic and / or dermatological compositions.

Description

[Technical field]

[0001] The present invention relates to the general technical field of substances and mixtures used in the field of formulating cosmetic and / or dermatological compositions, in particular to mixtures of the type containing functional agents, e.g. of the pigment type.

[0002] More specifically, the present invention relates to mixtures that include at least 50% by weight of a functional agent.

[0003] The present invention also relates to a process for the preparation of such a mixture.

[0004] Finally, the present invention relates to a method for producing a cosmetic and / or dermatological composition. [Background technology]

[0005] The manufacture of cosmetic and / or dermatological compositions usually requires the combination and mixing of several substances and compounds into a homogeneous material, i.e. in which the various compounds and substances are regularly distributed and stable, i.e. which does not undergo phase separation over time, in particular by sedimentation or creaming, or by other undesirable phenomena such as coalescence or aggregation.

[0006] For this purpose, it is known to have recourse to solid pigments that are ground into fine particles by a grinding unit before being incorporated into the cosmetic composition to color or enhance its matte or glossy appearance. Although they are generally satisfactory in their final use, the introduction of these ground pigments still has some drawbacks.

[0007] One major drawback of the use of these ground pigments in the manufacture of cosmetic compositions lies in their grindability, which makes the storage, transport and handling of these ground pigments complicated, expensive, dirty and even polluting, while also characterizing non-negligible risks in terms of biological and equipment safety, as well as great difficulties in terms of cleaning and / or removal of these ground pigments. In general, the finer the grinding of the pigments and therefore the smaller the pigment particles, the more complex their management. Moreover, the powder state of these pigments gives them a large specific surface area (actual surface / low mass), which results in considerable reactivity and therefore an increased risk of degradation, especially over time, and even of accidents, especially explosions.

[0008] Moreover, the grinding units are very often specialized and very expensive, while the grinding process itself can be particularly long and complicated, depending on the nature and the desired size of the ground pigment particles, which can vary, for example, depending on aesthetic, sensory and / or qualitative requirements. In most cases, due to the cost and complexity, these grinding units are not dedicated to a specific grinding of pigments, and therefore need to be set up to grind pigments according to other specifications, such as different particle sizes, or to grind other types of pigments. These grinding units therefore process different "batches" or sets of ground pigments of several types and sizes, which must be stored, transported and used later in different cosmetic composition production units. This, on the one hand, results in an increase in batches of powdered pigments that are difficult to handle (storage, transport, handling, especially during mixing with other substances to carry out the formulation of the cosmetic composition, avoiding the mixing of different pigments), and, on the other hand, in the fact that the cosmetic composition production units are almost always separate and remote from the grinding units, which further complicates the management (especially transport) of the ground pigments.

[0009] Finally, the incorporation of ground pigments into cosmetic compositions, as currently practiced, is deficient in terms of ease of implementation, storage, transportation, safety, and cost. Summary of the Invention

[0010] As a result, the present invention proposes to overcome the different drawbacks mentioned above by providing a new mixture that not only proves to be easily incorporated (integrated) into cosmetic and / or dermatological compositions, but which is, moreover, very easy to implement in terms of its management, in particular with regard to its transport, storage and handling.

[0011] Another object of the present invention is to provide a new mixture of very simple and inexpensive design.

[0012] Another object of the invention is to provide new mixtures which are particularly easy to handle.

[0013] Another object of the present invention is to provide a new mixture which is particularly easy to transport and store.

[0014] Another object of the present invention is to provide new mixtures which are easy to effectively incorporate into cosmetic and / or dermatological compositions.

[0015] Another object of the present invention is to provide new mixtures designed to allow good reproducibility as ingredients in the formulation of cosmetic and / or dermatological compositions.

[0016] Another object of the present invention is to provide new mixtures whose design allows their use in a wide range of applications, in particular in a very wide variety of cosmetic and / or dermatological compositions.

[0017] Another object of the present invention is to provide a new mixture that poses minimal risks to biosafety and does not degrade equipment.

[0018] Another object of the present invention is to provide new mixtures whose production can be easily industrialized and which incorporate a minimum number of different substances.

[0019] Another object of the present invention is to provide new mixtures that exhibit little or no decomposition over time.

[0020] Another object of the present invention is to provide a method for the preparation of a mixture which is simple, easy and cost-effective to carry out, has good reproducibility and good safety for the user.

[0021] Another object of the present invention is to provide a method for the preparation of cosmetic and / or dermatological mixtures, the implementation of which is quick, easy to monitor and simple, whilst ensuring optimal safety conditions.

[0022] The object of the present invention is achieved by a mixture comprising at least 50% by weight of a functional agent, which also comprises a waxy matrix in which the functional agent is dispersed, the mixture being solid at room temperature and intended to be dispersed in the cosmetic and / or dermatological composition by fluidization and / or solubilization, and to incorporate the functional agent into the cosmetic and / or dermatological composition, the functional agent being formed by surface-treated solid particles which have been subjected to a surface treatment that causes a decrease in the absorption capacity of the waxy matrix by the treated solid particles compared to untreated solid particles of the same type.

[0023] The object of the present invention is to - a heating step for heating the waxy matrix to obtain a fluid matrix; - a process for treating solid particles, during which the solid particles are subjected to a surface treatment which causes a decrease in the capacity of the treated solid particles to absorb a fluid matrix compared to untreated solid particles of the same type, the treated solid particles forming a functional agent; - dispersing a functional agent within a fluid matrix; At least The mixture is solid at room temperature and is intended to be dispersed in the cosmetic and / or dermatological composition by fluidization and / or solubilization to incorporate the functional agent into the cosmetic and / or dermatological composition. This is achieved by a method for preparing a mixture that contains at least 50% by weight of the functional agent.

[0024] The object of the present invention is achieved by a method for the preparation of a cosmetic and / or dermatological composition comprising a redispersion step in which the aforementioned mixture is added and then mixed with one or more cosmetically and / or dermatologically acceptable ingredients. [Brief description of the drawings]

[0025] Other particularities and advantages of the invention will appear in more detail and become apparent on reading the description which follows, with reference to the attached drawings, given purely as illustrative and non-limiting examples, in which:

[0026] [Figure 1] FIG. 2 shows, in a side view, a schematic example of a mixture according to the invention, in the form of a stick obtained by extrusion.

[0027] [Diagram 2] 2 shows a schematic diagram of a detail of the mixture of FIG. 1 on a microscopic or nanometer scale.

[0028] [Diagram 3] 1 shows, in a side view, a schematic part of an example of a manufacturing device making it possible to carry out a method for manufacturing a mixture according to the invention, according to a particular embodiment carrying out an extrusion step. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] As shown in the figure, the invention relates to a mixture 1. Mixture 1 is therefore preferably formed by several different elements, more particularly by a relatively homogeneous and stable mixture of several different substances, materials, objects, advantageously all cosmetically and / or dermatologically acceptable, i.e. suitable for incorporation into cosmetic and / or dermatological compositions. Mixture 1 therefore advantageously has a very low, possibly even zero, toxicity level with respect to the use of cosmetic and / or dermatological compositions. Thus, according to the invention, mixture 1 comprises at least 50% by weight of functional agents. According to a preferred embodiment, mixture 1 comprises (strictly) more than 50% by weight, preferably (strictly) more than 60% by weight, more preferably at least 70% by weight, even more preferably at least 80% by weight, even more preferably at least 85% by weight, even more preferably at least 90% by weight of functional agents. Advantageously, the functional agents are appropriately selected to form elements suitable for incorporation into cosmetic and / or dermatological compositions. Thus, a high proportion of functional agents in mixture 1 is particularly advantageous when mixture 1 constitutes an intermediate (or possibly near-final) product that is intended to be redispersed with other compounds to form the final cosmetic and / or dermatological product, as will be explained in more detail below. In fact, mixture 1 advantageously serves as an intermediate "carrier" or "vehicle" for the functional agents, and therefore it is preferable that the proportion of functional agents in mixture 1 is as high as possible, on the one hand for a final formulation (i.e. the final cosmetic and / or dermatological product) that does not or hardly depends on the properties of substances other than the functional agents in mixture 1, and on the other hand for obvious reasons related to costs, storage and transportation, intermediate mixtures with a low content of functional agents must, by definition, be used in larger amounts and therefore occupy a generally larger volume for a given amount of functional agent by weight, while the larger proportions of substances other than the functional agents in mixture 1 represent a high cost that is not, moreover, evaluated in the final formulation (and possibly "parasitic" on the final or final cosmetic and / or dermatological formulation).Preferably, the functional agent is intended to fulfill one or more very specific functions within the cosmetic and / or dermatological composition. For example, the functional agent is intended to form a physical sunscreen, especially within a cosmetic and / or dermatological composition of the suncream type, i.e. it is intended to form a physical, preferably opaque, barrier between the UV rays of the sun and the skin of the user of the cosmetic and / or dermatological composition.

[0030] According to the invention, the functional agent is formed by solid particles 2, i.e. the solid particles 2 are preferably solid at least at room temperature and even at higher temperatures, for example 30-90°C. Preferably, the solid particles are insoluble in water. Preferably, the solid particles have an average size comprised in the range of 10 nm to 500 μm, preferably comprised in the range of 100 nm to 100 μm. The average size therefore preferably refers to the average particle size of the particles 2, in particular their average diameter or average maximum dimension of the particles, which can be measured using only one sample of the particles.

[0031] The solid particles 2 comprise at least organic and / or mineral (i.e. inorganic) pigments, organic and / or mineral charges, composites and / or biocomposites, or mixtures thereof. According to certain embodiments, the solid particles 2 are formed mainly or entirely by mineral pigments, which may be constituted, for example, by titanium dioxide, iron oxide, chromium oxide, ultramarine pigments (for example ultramarine or purple), tin oxide, and / or zinc oxide. For example, the organic pigments are constituted by carbon black and / or organic lacquers. For example, the mineral charges are constituted by talc, mica, sericite, kaolin, silica, hydroxyapatite, barium sulfate, perlite, calcium carbonate, and / or borosilicates. For example, the organic charges are constituted by starch, cellulose, natural or synthetic polymers, and / or siliconized polymers and resins. For example, the composites and / or biocomposites include one or more nacres. If the solid particles consist of pigments, the functional agents are intended, for example, to color the cosmetic and / or dermatological formulation or to protect the skin from the sun (in the case of the aforementioned sunscreen cream, in particular the solid particles 2 forming the sunscreen). If the solid particles 2 consist of charges, the functional agents may, for example, be intended to modify the sensory properties of the cosmetic and / or dermatological formulation.

[0032] Further according to the invention, the mixture 1 also comprises a waxy matrix 3 in which the functional agent is dispersed. In other words, the functional agent, more particularly the solid particles 2, is advantageously mixed with the waxy matrix 3 and dispersed within the waxy matrix 3, preferably uniformly, i.e. according to a regular volume distribution. Advantageously, within the mixture 1, the waxy matrix 3 and the solid particles 2 form, from a macroscopic point of view, one single phase, and it is impossible to distinguish the waxy matrix 3 from the solid particles 2 with the naked eye.

[0033] For example, the waxy matrix 3 comprises at least one natural, mineral and / or synthetic wax, a fatty solid at room temperature derived from the distillation of one or more natural and / or synthetic oils, a natural and / or synthetic resin, a silicone or silicone polymer wax, an organosilicon (or organosilicon) material, or a mixture thereof. For example, the organosilicon material (or a number of different organosilicon materials) belongs to the group of silsesquioxanes, which have the general formula (RSiO 3 / 2 ) nwhere R represents a carbonate group, in particular of alkane, alkene, aryl or arylene type, while, as usual, Si represents a silicon atom, O represents an oxygen atom and n represents an integer generally greater than 1, for example from 3 to 20, for example equal to 8. Advantageously, the organosilicon material is a silsesquioxane polymer. According to a particular embodiment of the invention, the waxy matrix 3 comprises polymethylsilsesquioxane, for example formed mainly by polymethylsilsesquioxane. Polymethylsilsesquioxane is a type of organosilicon material that is particularly effective when used as the waxy matrix 3. According to other particular embodiments, the waxy matrix 3 comprises mainly (by weight) or not, cyclopentasiloxane, at least one (C30-C45) alkylmethicone, and / or a hydrogenated ester, such as a hydrogenated ester of a vegetable oil, for example an olive oil hydrogenated ester with the INCI name "hydrogenated olive oil stearyl ester". Of course, the waxy matrix 3 may be formed by a mixture of several substances, especially among those mentioned above. Preferably, this organosilicon material is an organosilicon material. Preferably, the waxy matrix 3 is substantially solid at room temperature, in particular below 30°C, preferably below 45°C, more preferably below 55°C, even more preferably below 65°C. Conversely, the waxy matrix 3 is advantageously substantially fluid at temperatures higher than room temperature, for example at temperatures above 30°C, preferably above 45°C, more preferably above 55°C, and even more preferably above 65°C. Thus, advantageously, the waxy matrix 3 has a melting point and / or softening point comprised in the range of 30-150°C, more preferably 45-130°C, even more preferably 55-130°C. In some embodiments of the present invention, the waxy matrix 3 has a melting point and / or softening point comprised in the range of 55-150°C, for example 55-95°C, or 95-150°C.For example, the waxy matrix 3 has a density comprised in the range of about 0.80 to 1.5, preferably comprised in the range of 0.9 to 1.3, for example being about 1.24, when the waxy matrix 3 is formed mainly or entirely by polymethylsilsesquioxane. For example, in particular when the waxy matrix 3 is formed mainly or entirely by polymethylsilsesquioxane, its softening point is advantageously comprised in the range of 55 to 150°C, or comprised in the range of 75 to 90°C. Preferably, the waxy matrix 3 is formed by a material having similar or comparable general physical properties to wax, in particular a material that becomes significantly more fluid above a certain temperature, i.e. that loses its solidity or switches from a very high viscosity to a much lower viscosity when heated above a certain temperature. For example, the waxy matrix 3 is formed by a substantially thermofusible and / or thermoplastic material that significantly softens and / or melts when heated above a certain temperature, for example above 65°C. Thus, the waxy matrix 3 is preferably solid at room temperature and preferably becomes substantially fluid when it is at a certain temperature above room temperature, in particular above its melting and / or softening point. Advantageously, the waxy matrix 3 may be formed by a plurality of solid granules separate from one another at room temperature, i.e. difficult or impossible to compress by mechanical pressure. It is particularly advantageous that the waxy matrix 3 is solid at room temperature, since this preferably allows the mixture 1 to remain in solid form at room temperature, and the waxy matrix 3 may determine the physical behavior of the mixture 1, in particular when the functional agent itself is formed by a solid substance at room temperature.

[0034] According to the invention, mixture 1 is solid at room temperature and is intended to be dispersed in the cosmetic and / or dermatological composition by fluidization and / or solubilization to incorporate the functional agent in the cosmetic and / or dermatological composition. Advantageously, mixture 1 has a relatively hard, non-loose, consistency, i.e. a minimum mechanical strength, substantially distinguished from a fluid, in particular a liquid, for example at room temperature or below 30° C. or below 45° C. For example, mixture 1 is in the form of granules, for example pellets or sticks 4, obtained by extrusion, as shown in FIG. 1 and FIG. 3. Preferably, mixture 1 is intended to be incorporated or taken into the cosmetic and / or dermatological composition during compounding (i.e. during manufacture). In other words, mixture 1 is advantageously intended to be mixed, preferably homogeneously, with cosmetically and / or dermatologically acceptable ingredients to form the cosmetic and / or dermatological composition. Advantageously, the incorporation of mixture 1 in the cosmetic and / or dermatological composition is carried out by any of the following actions, as will be shown in more detail later in this method: - through the fluidization obtained by heating the mixture 1, i.e. generally through the loss of the solid nature of the mixture 1 due to softening or melting of the solid particles and / or the waxy matrix 3 (at least in part, since the solid particles advantageously do not fluidize); the subsequent mixing ("at high temperature") of the fluid mixture 1 with cosmetically and / or dermatologically acceptable ingredients for the formation of a cosmetic and / or dermatological composition may be facilitated, since the ingredients ("at high temperature" or not) are advantageously also mainly in fluid form; - through solubilization of the mixture 1 by one or more cosmetically and / or dermatologically acceptable ingredients to form a cosmetic and / or dermatological composition, these compositions being preferably mainly in fluid form, at least one of these ingredients being able to solubilize the mixture 1, especially when the mixture 1 is "cold" (i.e. below room temperature, especially about 20°C or 30°C), which of course may possibly be "hot" (in which case mixing by fluidization is described above, a combination of fluidization and solubilization is of course possible). According to a non-limiting embodiment provided for illustrative purposes only, the mixture 1 comprises a waxy matrix 3 formed mainly by silicone waxes, which are easily dissolved by cosmetically and / or dermatologically acceptable ingredients, especially of the oil type, and the mixture 1 is advantageously easily dissolved in the cosmetically and / or dermatologically acceptable ingredients to form the cosmetic and / or dermatological mixture.

[0035] The cosmetic and / or dermatological composition may be directly intended for a single user or may form an intermediate product, which is intended to incorporate the cosmetic and / or dermatological product, which is either a final product intended for a user, or an intermediate product.

[0036] The mixture 1 advantageously results from the mixing of the functional agent, i.e. the particles 2, with the waxy matrix 3, and is preferably not powdery, but is cohesive and easy to "redisperse" in the cosmetic and / or dermatological composition during formulation in fluid form. At low temperatures, i.e. at room temperature, the mixture 1 advantageously constitutes a solid dispersion in the same manner as a set of solid particles 2 dispersed in a waxy matrix 3 that is also solid at low temperatures. Preferably, such a configuration makes it possible to remove the constraints associated in particular with the nature of the solid particles 2 alone, which are often powdery in nature. Thus, preferably, the mixture 1 is substantially easier to manage, i.e. to store, transport and handle, than the particles 2 alone, in particular because the mixture 1 is, for example, in the form of small solids (e.g. pellets or stick 4 type granules), cohesive, relatively inert and easy to handle at room temperature, while the particles 2, on the contrary, when they are alone, are often of a very finely divided, powdery nature, highly reactive and highly dispersible in air. Advantageously, the mixture 1 is formed at room temperature by solids separate from one another, preferably in reduced size, such as granules, e.g. sticks, pellets 4, etc., which are preferably difficult or incompressible to compress by mechanical pressure. The mixture 1 is therefore easy to store and transport in the form of (small) separate solids stored in a container, e.g. stored in a bag, of (at least) several kilograms or several tens of kilograms, without the separate solids being separated from one another, e.g. by agglomeration, coalescence, compression or sedimentation. In other words, the mixture 1 is preferably easy to store and transport in the form of separate solids that remain separate from one another during transport and / or storage, even if this / these are carried out using containers such as weighed bags with their respective (separate solids, formed by several kilograms or several tens of kilograms) contents.Preferably, the separate solids formed by the mixture 1 remain easy to handle even after they have been stored and / or transported in a container, thanks to the lack of adhesion of the separate solids even when they are stored, the separate solids maintaining the properties of their respective units despite storage. Of course, said transport is preferably carried out at room temperature or slightly above room temperature, but advantageously remaining below the melting and / or softening point of the waxy matrix 3. Thus, the mixture 1 is not only practical for transport and storage, but also for quantifying when the separate solids, in particular the granules (e.g. pellets or sticks 4), should be dispersed in the cosmetic and / or dermatological composition. In particular, this allows easy quantification of the amount of functional agent obtained in the final cosmetic and / or dermatological composition, which means good reproducibility when formulating cosmetic and / or dermatological compositions thanks to the mixture 1.

[0037] According to the invention, the solid particles 2 are subjected to a surface treatment which causes a decrease in the absorption capacity of the waxy matrix 3 by the treated solid particles 2 compared to untreated solid particles of the same type. In other words, the solid particles 2 forming the functional agent of the mixture 1 are advantageously surface-treated, which allows them to be "saturated" more quickly with the waxy matrix 3, i.e. a smaller amount of waxy matrix 3 is used compared to the amount of solid particles 2 considered. For example, the absorption limit (or "saturation") of a waxy matrix 3 with a certain amount of solid particles 2 (whether treated or not) is tested as follows: a certain amount (more than necessary) of waxy matrix 2 is heated so as to become fluid, for example to 65°, and is added drop by drop to a considered amount of solid particles 2 (whether treated or not), which are preferably simultaneously subjected to a mixing or grinding action; the mixture of mixed or ground solid particles 2 / droplets of waxy matrix 3 initially forms a very viscous, even solid or almost solid paste, for example in the same way as plasticine, and then, upon further addition of drops of waxy matrix 3, its viscosity decreases significantly and / or it switches from a solid or almost solid state to a fluid or almost fluid state (in particular liquid or softened). Thus, the surface treatment advantageously allows to reduce the amount of fluid waxy matrix 3 added to the amount of solid particles 2 considered, in order to cause their mixture to lose its consistency, i.e. to switch from a very viscous solid or almost solid state to a significantly less viscous fluid or almost fluid state. Surface treatments that allow to cause a decrease in the absorption capacity of the waxy matrix are known per se and are modified by several alternative methods, and the invention is of course not limited to a specific treatment. As a non-limiting example, the surface treatment of solid particles 2 carried out in the context of the present invention can be based on a treatment based on amino acids, for example N-acylamino acids such as N-acyl-L-glutamic acid, advantageously following the teachings of US-4,606,914.For example, the surface treatment is based on a treatment based on amino acids in the form of metal salts of N-acylamino acids, such as the salt made from sodium myristoyl glutamate and aluminum hydroxide. Of course, other surface treatments according to the invention can be considered, which can be based, for example, on: treatments implementing disodium myristoyl glutamate, advantageously aluminum dimyristate and triethoxycaprylylsilane; treatments implementing alkoxysilanes such as triethoxycaprylylsilane; treatments according to the teachings of US-6482441, treatments implementing fatty acids, treatments implementing one or more phospholipids, treatments implementing olive oil hydrogenated esters, etc. For example, the surface-treated solid particles 2 are formed, by way of purely illustrative and non-limiting example, by raw pigments (preferably more than 90% by weight), sodium myristoyl glutamate (preferably less than 10% by weight) and aluminum hydroxide (preferably less than 10% by weight). Surface treatments making it possible to cause a decrease in the absorption capacity of the waxy matrix can further be formed by a combination of the different treatments listed above. Advantageously, the surface treatment which makes it possible to cause a decrease in the absorption capacity of the waxy matrix also makes it possible to increase the hydrophobicity of the treated solid particles 2 and / or to improve their dispersibility in the oil phase compared to untreated solid particles of the same type.

[0038] Advantageously, the functional agent forms (strictly) more than 50% by weight, preferably more than 60% by weight, more preferably at least 70% by weight, even more preferably at least 80% by weight, even more preferably at least 85% by weight, or even at least 90% by weight of the mixture 1. Thus, preferably at least 70% by weight, preferably at least 80% by weight, or at least 85% by weight of the mixture 1 is formed by the solid particles 2. Such a high weight proportion of functional agent (and thus particles) is advantageously possible thanks to the surface treatment. The waxy matrix forms preferably 5-25% by weight, preferably 7-22% by weight, more preferably 15-20% by weight of the mixture 1. In summary, advantageously, thanks to the surface treatment, a relatively small amount of the waxy matrix 3 is sufficient to act as a carrier for a relatively large amount of the solid particles 2.

[0039] Preferably, when the mixture 1 is fluidized and / or solubilized, the mixture 1 and thus the functional agent (and more specifically the solid particles 2) contained thereby can be dispersed or mixed in a uniform and stable manner in the cosmetic and / or dermatological composition. In summary, thanks to the general principles of the present invention, in particular thanks to the surface treatment, it is advantageously possible not only to obtain an easy-to-handle mixture 1 containing a large amount of the functional agent (at least 50% by weight, preferably at least 80% by weight, or even more preferably at least 85% by weight) and a small amount of the waxy matrix 3, but also to subsequently easily disperse the mixture 1 in the cosmetic and / or dermatological composition during manufacture in order to incorporate the functional agent in the cosmetic and / or dermatological composition. Advantageously, the waxy matrix 3 and thus the mixture 1 act as a carrier for the functional agent before redispersion in the cosmetic and / or dermatological composition. Preferably, redispersion of mixture 1 can be carried out by fluidization, thus heating mixture 1 until it becomes fluid so that it can be mixed more easily with the cosmetically and / or dermatologically acceptable ingredient which is itself a fluid, or by solubilization of mixture 1, preferably in the form of a small solid (granules of particles, e.g. pellets or sticks 4), optionally at low temperature (i.e. without heating), within the cosmetically and / or dermatologically acceptable ingredient which is a fluid.

[0040] Furthermore, the relatively small or limited amount of waxy matrix 3 in mixture 1, and the properties of mixture 1, advantageously allow mixture 1 to be incorporated into a wide range of cosmetic and / or dermatological compositions. In other words, the design of mixture 1 advantageously allows the functional agents contained thereby to be incorporated into cosmetic and / or dermatological compositions without any or almost no constraints regarding other components of the cosmetic and / or dermatological composition, i.e., there is no need to modify these other components forming the cosmetic and / or dermatological composition to make them compatible with mixture 1. In summary, mixture 1 of the present invention can be advantageously incorporated into a wide range of cosmetic and / or dermatological compositions.

[0041] Preferably, the waxy matrix 3 is lipophilic and / or insoluble or almost insoluble in water. The waxy matrix 3, which advantageously has physical properties close to or similar to those of natural or synthetic waxes (especially silicone waxes), is therefore preferably lipophilic, lipophilic and / or hydrophobic in nature. In particular, the waxy matrix 3 is soluble in oil phases commonly used in the manufacture of cosmetic and / or dermatological compositions. Advantageously, the waxy matrix 3 is intended to be incorporated relatively easily into the cosmetic and / or dermatological composition due to its relative low amount in the mixture 1, which mixture is preferably intended to be incorporated without significantly modifying the physical and / or chemical properties of the composition, which is even easier if the composition has a fat or oil (and / or lipophilic) phase, optionally in an emulsion of the water-in-oil, e.g. water-in-silicone or oil-in-water type.

[0042] Mixture 1 may optionally be intended to be redispersed to become part of a cosmetic and / or dermatological composition containing only an anhydrous phase, preferably of the fat / oil / silicone type, such as, for example, a balm, lipstick, etc.

[0043] Advantageously, the surface treatment also makes it possible to increase the lipophilic and / or hydrophobic properties of the treated solid particles 2 compared to untreated solid particles 2 of the same type. The surface treatment therefore confers on the solid particles 2 a chemical affinity for fats and fatty substances or strengthens the chemical affinity for fats and fatty substances in the solid particles 2, advantageously the same encompassing the waxy matrix 3. In particular, such a feature makes it possible to obtain a better dispersion of the solid particles 2 within the waxy matrix 3 and / or a better dispersion of the mixture 1 (and thus the solid particles 2 themselves) within the cosmetic and / or dermatological composition (and thus in particular comprising an oil phase or equivalent).

[0044] Preferably, the surface treatment comprises the grafting of molecules 5 to the surface of each of the particles 2, as shown in Figure 2. Still more preferably, the grafted molecules 5 comprise at least siliconized chains, carbonate chains, natural or synthetic polymers, organic molecules, or titanium oxides or silicon oxides. Thus, advantageously, the mixture 1 comprises, in particular, a waxy matrix 3 and treated particles 2, the particles 2 comprising and / or including grafted molecules 5. Preferably, the particles 2 are homogeneously dispersed within the waxy matrix 3, at least in part thanks to the grafted molecules 5, and thus the presence of the grafted molecules 5 preferably enhances the lipophilic and / or hydrophobic nature of the particles 2 and / or advantageously reduces the absorption capacity of the particles 2 of the waxy matrix 3.

[0045] Advantageously, the functional agent and the waxy matrix 3 together form at least 95% by weight, preferably at least 97% by weight, more preferably at least 99% by weight, and even more preferably all, of the mixture 1. Indeed, whether for making the mixture 1 or for dispersing it in a cosmetic and / or dermatological composition, it is advantageously not necessary to incorporate components other than the waxy matrix 3 and the functional agent into the mixture 1, although this can still be taken into consideration. Thus, preferably, the mixture 1 does not contain surfactants, i.e. in particular does not contain any substance whose main function is to reduce the surface tension, or the mixture 1 contains such substances, but in amounts that are not useful and are negligible in weight relative to the waxy matrix 3 and / or the functional agent.

[0046] The present invention also relates to a method for producing a mixture 1, preferably as described above (or below), according to a second aspect, which is partly illustrated by the embodiment of FIG. 3. The method of the present invention thus makes it possible to produce a mixture 1, preferably as described above, which comprises at least 50% by weight of functional agent, the mixture 1 possibly comprising (strictly) more than 50% by weight, preferably (strictly) more than 60% by weight, more preferably at least 70% by weight, even more preferably at least 80% by weight, or even 85% by weight of functional agent. The above-mentioned explanations regarding the mixture 1 therefore advantageously also apply to the production method according to the invention (and conversely, the following explanations regarding the production method therefore also apply to the mixture 1 according to the invention).

[0047] According to the invention, the manufacturing method comprises at least one step of heating the waxy matrix 3 to obtain a fluid matrix 3. C and the wax-like matrix 3 is preferably as described above. In other words, the heating step C During the heating step, the waxy matrix 3 is heated, for example using at least one resistor or by convection, until it becomes fluid, i.e. it is melted or softened sufficiently so that it no longer has a solid consistency, thereby forming a fluid waxy matrix 3. During the heating step, the waxy matrix 3 is advantageously heated to a temperature equal to or higher than its melting and / or softening point. Thus, during the heating step, the waxy matrix 3 is heated, for example, to a temperature comprised in the range 30-150°C, more preferably to a temperature comprised in the range 45-130°C, or to a temperature comprised in the range 55-95°C, or to a temperature comprised in the range 55-150°C, so that it becomes fluid. Thus, preferably, at low temperatures, the waxy matrix 3 is almost solid, whereas at high temperatures, above a certain temperature, it is almost fluid. Thus, preferably, the expression "fluid matrix" refers to a waxy matrix 3 heated until it becomes fluid.

[0048] According to the invention, the method also comprises a step of treating solid particles 2 T(not shown) T During the treatment, the solid particles 2 are surface-treated to cause a reduction in the absorption capacity of the fluid matrix 3 by the treated solid particles 2 compared to untreated solid particles 2 of the same type, and the treated solid particles 2 form a functional agent. Preferably, the solid particles 2 are as described above. In particular, as described above, the treatment step T advantageously involves the grafting of molecules 5 to the surface of each of the particles 2 and / or an increase in the lipophilic and / or hydrophobic properties of the treated solid particles 2 compared to untreated solid particles of the same type.

[0049] Further according to the invention, the method further comprises a dispersing step of dispersing a functional agent in the fluid matrix 3. D Advantageously, the dispersion step D at least one step of mixing the treated particles 2 with a waxy matrix 3 M wherein the waxy matrix 3 may in particular be in solid form at low temperatures or in flowable form at high temperatures.

[0050] According to the present invention, and advantageously as described herein, mixture 1 is solid at room temperature and is intended to be dispersed in cosmetic and / or dermatological compositions by fluidization and / or solubilization, and to incorporate functional agents into the cosmetic and / or dermatological compositions.

[0051] Advantageously, the method further comprises subjecting the solid particles 2 to a grinding step intended to reduce their average size. B For example, the grinding step B Upon completion of the process, the solid particles 2 have an average size generally comprised between 10 nm and 500 μm, preferably between 100 nm and 100 μm.

[0052] Preferably, a dispersion step is performed as shown in FIG. D However, at least in part, the grinding process B As a result, the grinding process B During at least a portion of the time, a fluid matrix 3 is mixed with the particles 2 .

[0053] According to a particular embodiment of the invention, as shown in FIG. 3, the method comprises an extrusion step of the mixture 1 so that the mixture 1 is in the form of granules, for example in the form of pellets or sticks 4. E Advantageously, the extrusion step E is carried out at an elevated temperature, the mixture 1 having a temperature comprised between 60 and 80° C. during this step.

[0054] Advantageously, the dispersion step D After step 1, the method also includes a cooling step in which mixture 1 is cooled to room temperature to form a solid. F Also includes.

[0055] According to an embodiment shown in FIG. 3 and provided for illustrative and non-limiting purposes, the method comprises in succession: -Mixing process M , mixing process M During this time, the treated solid particles 2 and the waxy matrix 3 are mixed at low temperature, the matrix 3 being solid and in the form of solid balls at low temperature (room temperature), while the particles 2 are in coarse morphology and of too large an acceptable particle size. -Heating process C , heating process C During this time, the waxy matrix 3 is heated and therefore fluidized, while the particles 2 remain solid. -Crushing process B , Crushing process B during which the particles 2 are broken down to an acceptable particle size while remaining intimately mixed / mixed with the fluid matrix 3 which is also subject to some type of comminution; -Homogenization process H , homogenization process H During this time, the mixture formed by the ground particles 2 and the fluid matrix 3 is homogenized by any suitable means (stirring, blowing, shearing, etc.), -Extrusion process E , Extrusion process E During this time, the hot mixture is compressed and passes through a die 6, resulting in a long product in the form of a cylinder. -Cooling process F , cooling process F During this time, the long product is gradually cooled. -Cutting process S , cutting process S During the process, the long product is cut and separated into a plurality of solids, preferably granules, e.g. pellets or sticks 4, which are separate from each other; mixture M ,heating C , Crushing B , and homogenization H The dispersion step herein includes the steps of D .

[0056] Advantageously, and particularly according to this embodiment, the method comprises the use of a twin screw heater extruder 7 in which the steps disclosed below are carried out.

[0057] It is particularly advantageous to carry out the grinding step B in such a way that the (average) particle size of the solid particles 2 is reduced and the ground solid particles 2 are mixed with the fluid matrix 3 (so that the fluid matrix 3 is also ground in some way). B During this grinding process, the particles 2 are milled in the presence of a fluid matrix 3. B is the mixing process M In this case, all that is required is to grind the waxy matrix 3 mixed with the solid particles 2, so the grinding step B is particularly simple and easy to carry out. B Thanks to this, the extrusion process may be carried out E (which is preferably carried out later) is significantly easier. Ballows a switch from finely grinding the solid particles 2 before mixing them with the waxy matrix 3, which thus avoids the need to handle very fine solid particles 2, which have a very dusty nature and hence disadvantages in terms of storage, safety and implementation. Comparative tests further show that the grinding step B is a step that is much smaller than the grinding step B compared to a mixture having solid particles 2 that are equivalent but not produced by a method including a grinding step B and therefore the particle size remains substantially the same throughout the production process. B has been demonstrated in the example of mixture 1 of the invention to give excellent dispersibility in the fatty phase (eg of a cosmetic composition).

[0058] The present invention also relates to a method for the preparation of a pharmaceutical composition comprising the steps of: (a) preparing a pharmaceutical composition comprising a step (b) and a step (c) of preparing a pharmaceutical composition comprising a step (d) of preparing a pharmaceutical composition comprising a step (e) of preparing a pharmaceutical composition comprising a step (f) of preparing a pharmaceutical composition comprising a step (g) of preparing a pharmaceutical composition comprising a step (h) of preparing a pharmaceutical composition comprising a step (i) of preparing a pharmaceutical composition comprising a step (i) of preparing a pharmaceutical composition comprising a step (ii) of preparing a pharmaceutical composition comprising a step (i ... R Advantageously, the above explanations regarding mixture 1 and the method for producing mixture 1 also apply to the method for producing the composition according to the invention.

[0059] According to a first variant, a redistribution step R further comprises a step of solubilizing mixture 1 by means of one or more of the cosmetically and / or dermatologically acceptable ingredients. Advantageously, the solubilization step comprises at least the solubilization (i.e. in particular the dispersion) of mixture 1 within the fatty phase (in particular the oil) or part of the fatty phase of the cosmetic and / or dermatological composition.

[0060] According to a second variant, which is compatible with the first variant described above, a redispersion step R The method further includes a fluidization step, in which the added mixture 1 is heated at least until it becomes fluid. R may also include solubilization and fluidization steps, for example, one after the other, or according to another example, simultaneously.

[0061] Preferably, the redispersion step RWith respect to, and in particular with respect to, the solubilization and / or fluidization steps, one or more of the cosmetically and / or dermatologically acceptable ingredients are substantially fluid at room temperature, thereby facilitating redispersion of mixture 1, either by its solubilization and / or its fluidization.

[0062] In order to highlight the improved content of solid particles 2 in mixture 1, different examples of mixture 1 according to the invention, designated A1 to A3, i.e. containing surface-treated solid particles 2 which cause a decrease in the absorption capacity of the waxy matrix, have been made for illustrative and non-limiting purposes only. Examples of mixtures designated A4 to A6 have also been made, but are not in accordance with the invention, i.e. in this case they contain the same type of solid particles as the solid particles of the examples of mixtures A1 to A3, but the solid particles are not surface-treated.

[0063] The examples of mixtures A1 to A6 were prepared according to Table 1 with respect to their respective solid particles (pigments in this case).

[0064] TIFF0007659504000001.tif120154

[0065] In these examples, the solid particles of mixtures A4 to A6 consist of untreated pigments, the INCI, CAS and EINEC names of which are reported in Table 1. In these non-limiting examples, the solid particles 2 of mixtures A1 to A3 consist of treated pigments, i.e. of solid particles 2 (of pigment type) that have been subjected to a surface treatment which causes a decrease in the absorption capacity of the waxy matrix. The respective trade names (as of the filing date of this patent application) of these treated pigments are reported in Table 1. The treated pigments of mixtures A1 to A3 are commercialized in particular under the respective trade names by the company Miyoshi.

[0066] Each of these examples of mixtures A1 to A6 has been prepared in a number of respective formulations, each containing one of the following respective weight ratios of solid particles / waxy matrix: 40 / 60, 50 / 50, 60 / 40, 70 / 30, 80 / 20 and 85 / 15. Thus, 36 different formulations of these examples of mixtures have been prepared, 18 of which are formulations of the example of mixture 1 according to the invention (A1 to 14) and 18 of which are not (A4 to A6). Of course, the waxy matrix 3 used is the same for all examples of mixtures A1 to A6, for example formed by polymethylsilsesquioxane. For example, the example of mixture A1 refers to all the formulations of this example of mixture, i.e. the 6 formulations, each with a different (above mentioned) weight ratio of solid particles / waxy matrix.

[0067] For example, the surface treatment of the example pigments of mixtures A1 to A3 can be preferably carried out with a treatment based on amino acids, according to the teachings of US-4,606,914, the amino acids being in particular in the form of metal salts of N-acylamino acids. Thus, for example, the surface treatment consists of coating the raw, i.e. untreated solid particles (and in particular the pigments) with 0.5 to 10% by weight, relative to the weight of the raw solid particles, of one or more metal salts of N-acylamino acids. For example, the N-acylamino acid is N-acyl-L-glutamic acid, while the metal consists, for example, of aluminum, magnesium, calcium, zinc or titanium. For example, the metal salts of N-acylamino acids are made using sodium myristoyl glutamate and aluminum hydroxide. In particular, such surface treatments can be used for the examples presented herein, for illustrative and non-limiting purposes, as well as in the remaining description heretofore and below. The surface treatment, in particular the treatment using a metal salt of an N-acylamino acid, preferably increases the hydrophobicity and dispersibility in oil of the treated solid particles 2 compared to the (untreated) raw solid particles.

[0068] The examples of mixtures A1 to A6 are given herein at least by the heating process already mentioned. C , distributedD , and crushing B Furthermore, these examples of mixtures A1 to A6 were prepared by the method of the present invention, which comprises the steps of extrusion. E all in the form of solid granules at room temperature.

[0069] The results of the blending of the example mixtures are reported in Table 2. The reference "yes" refers to successful blending of a homogeneous mixture, i.e. in other words a homogeneous solid dispersion of pigment and waxy matrix, preferably easy to extrude, and the reference "no" refers to unsuccessful blending, the resulting blend being generally inhomogeneous and possibly partially powdery, resulting from poor distribution of the pigment and waxy matrix. As a rule, the higher the pigment content (i.e. the higher the solid particle content), the more difficult it is to achieve successful blending.

[0070] TIFF0007659504000002.tif62170

[0071] Thus, the preparation of solid dispersions of treated pigments A1 to A3 made it possible to obtain homogeneous solid formulations containing all of the tested contents of pigment, i.e. here 40 to 85% by weight of treated pigment.

[0072] However, in the formulation of the examples of mixtures A4 to A6, it was possible to obtain acceptable results only for relatively low pigment contents (40 and 50% by weight of untreated pigment). With more than 50% by weight of untreated pigment, it was not possible to obtain a formulation of a satisfactory homogeneous solid mixture, but only a powdery, inhomogeneous mixture of pigment and waxy matrix, which is poorly dispersible and further complicated to the extrusion process. E This may prevent the completion of

[0073] The above results demonstrate that the examples of mixtures 1 of the present invention demonstrate that the surface treatment of the solid particles 2 (pigments in these particular examples) makes it possible to significantly increase the concentration of the pigment solid particles in the wax-like matrix 3.

[0074] In order to highlight the excellent (re)dispersibility of Mixture 1, different examples of Mixture 1, designated A7 to A12 according to the present invention, have been prepared for illustrative and non-limiting purposes only and are reported in Table 3.

[0075] TIFF0007659504000003.tif98155

[0076] The treated pigments of mixtures A7 to A12 reported in Table 3 (and therefore consisting of solid particles that have been surface treated to cause a decrease in the absorption capacity of the waxy matrix) are the same as those of mixtures A1 to A3. The term "wax" in mixtures A7 to A9 in Table 3 refers, for example, to olive oil ester wax, while the silicone resin in mixtures A10 to A12 in Table 3 is formed, for example, by polymethylsilsesquioxane.

[0077] The examples of mixtures A7 to A12 are given herein at least by the heating process already mentioned. C , distributed D , and crushing B Furthermore, these examples of mixtures A7 to A12 were produced by the method of the present invention, which includes the steps of extrusion. E All are in the form of solid granules at room temperature according to the invention. The solid particles 2 (here different pigments) of these examples of mixtures A7 to A12 are preferably surface-treated according to the invention, for example using one or more metal salts of N-acylamino acids, according to the teachings of US-4,606,914.

[0078] The (re)dispersibility of the examples of mixtures A7 to A12 was evaluated by mixing each of them separately in different types of liquid fatty bodies (linear or branched alkane type apolar oil, or linear or branched ester type polar oil, or triglyceride type polar oil, or dimethicone type linear silicone oil, cyclopentasiloxane type cyclic silicone oil, or methyltrimethicone type branched silicone oil), according to a weight ratio of 1 part by weight of solid dispersion of pigment to 2 parts by weight of liquid fatty bodies. Each of these liquid fatty bodies may therefore be intended to form the fatty phase or part of the fatty phase of a cosmetic and / or dermatological composition. In other words, the evaluation of the dispersibility of the examples of mixtures A7 to A12 in these different fatty bodies makes it possible to evaluate the ability / ease of homogeneous dispersion of the examples of mixtures A7 to A12 in the respective cosmetic and / or dermatological composition.

[0079] The dispersibility of the example mixtures A7 to A12 in the respective liquid fat bodies was achieved by means of relatively common mixing equipment (such as a deflocculator turbine at 3300 rpm for 5-15 minutes or a disperser ultra-turrax® at 8000 rpm for 5-15 minutes). No fine grinding step of the pigments alone, for example in 3 cylinders, was carried out prior to the preparation of the example mixtures A7 to A12.

[0080] Example mixtures A7 to A9 are mixed with a liquid fat body at elevated temperature (between 60 and 80°C) to form mixtures M7 to M9, respectively. Example mixtures A10 to A12 are mixed with a liquid fat body at room temperature (25°C) to form mixtures M10 to M12, respectively.

[0081] The dispersibility (i.e. uniformity of distribution) of the example mixtures A7 to A12 in the respective liquid fat bodies was evaluated by observation of the mixtures M7 to M12 under an optical microscope, spread between two glass plates and on a grindometer (also called Hegman gauge) at 100 μm and 25 μm, and compared with compositions M7' to M12' containing the same types (but untreated in the case of the pigments) and proportions of pigments and liquid fat bodies as the mixtures A7 to A12. However, the pigments of compositions M7' to M12' are prepared in a fine grinding device (e.g. milling in a 3-cylinder) and dispersed directly in powder form in the respective liquid fat bodies, without intermediate dispersion in a waxy matrix, to form compositions M7' to M12'.

[0082] The above observations show that mixtures M7 to M12 in which the pigments have been surface treated and incorporated into the example mixtures A7 to A12 (and subsequently into mixtures M7 to M12) have the same fineness of grind (particle size, uniformity of dispersion) as mixtures M7' to M12' in which the pigments have been milled, for example with a 3-cylinder, but have not been surface treated or incorporated into the inventive mixture 1 intended to be redispersed.

[0083] According to the above results, the solid particles 2 (herein pigments) present in the examples of solid mixtures A7 to A12 according to the invention are uniformly dispersed in liquid fatty bodies (considered to be part of the cosmetic and / or dermatological composition) with a high content (by weight) of solid particles 2, which are demonstrated to be so over a limited period of time (normal mixing period). As a result, the mixture 1 according to the invention allows to obtain an excellent ease of redispersion of the solid particles 2, in particular the pigments, within the cosmetic and / or dermatological composition, in particular within the fatty (oil) phase of the cosmetic and / or dermatological composition.

[0084] Examples of cosmetic and / or dermatological compositions made according to the composition manufacturing method of the present invention, each incorporating at least one Mixture 1 according to the present invention, are described below for illustrative and non-limiting purposes.

[0085] Composition M20: skin foundation made with a water-in-silicone emulsion having the following composition (by weight): fat phase PEG-10 dimethicone type or PEG-20 dimethicone type or PEG-9 lauryl polydimethylsiloxyethyl dimethicone type surfactant: 3.00% Dispersion of Disteardimonium Hectorite and Propylene Carbonate: 1.00% Cyclopentasiloxane: 17.25% · Alkane-type non-polar oil or ester-type polar oil or triglyceride-type polar oil or dimethicone-type linear silicone oil or cyclopentasiloxane-type cyclic silicone oil: 10.00% Mixture 1 according to the invention, selected from among the examples of mixtures A7 to A12: 10.00% aqueous phase Magnesium sulfate: 0.75% Xanthan gum: 0.15% Butylene glycol: 5.00% Preservatives: 0.75% Demineralized water: appropriate amount

[0086] Composition M21: a water-in-oil emulsion having the following composition (by weight): fat phase Polyglyceryl-3-diisostearate type surfactant: 3.00% Wax: 2.00% Glyceryl behenate: 1.00% Isononyl isononanoate oil: 10.00% Alkane-type non-polar oil or ester-type polar oil or triglyceride-type polar oil or dimethicone-type linear silicone oil or cyclopentasiloxane-type cyclic silicone oil: 5.00% Mixture 1 according to the invention, selected from among the examples of mixtures A7 to A12: 10.00% aqueous phase Sodium chloride: 1.50% Magnesium sulfate: 1.50% Xanthan gum: 0.20% Butylene glycol: 3.00% Preservatives: 0.30% Demineralized water: appropriate amount

[0087] Composition M22: skin foundation made by water-in-oil emulsion at low temperature, having the following composition (by weight): fat phase Polyglyceryl-3-polyricinoleate type surfactants: 8.00% Dispersion of Disteardimonium Hectorite and Propylene Carbonate: 5.00% Alkane oil: 13.70% Amorphous silica type texturing agent: 5.00% Preservatives: 1.00% Mixture 1 according to the invention, selected from the examples of mixtures A10 to A12: 10.00% aqueous phase Sodium chloride: 1.00% Glycerin: 3.00% Xanthan gum: 0.30% Demineralized water: appropriate amount

[0088] Composition M23: anhydrous skin foundation in a stick having the following composition (by weight): fat phase Wax: 70.00% Alkane-type non-polar oil or ester-type polar oil or triglyceride-type polar oil or dimethicone-type silicone oil or cyclopentasiloxane-type silicone oil: 20.00% Mixture 1 according to the invention, selected from among the examples of mixtures A7 to A9: 10.00%

[0089] Composition M24: a lipstick having the following composition (by weight): fat phase Wax: 70.00% Alkane-type non-polar oil or ester-type polar oil or triglyceride-type polar oil or dimethicone-type silicone oil or cyclopentasiloxane-type silicone oil: 14.50% Amorphous silica type texturing agent: 5.00% Tocopherol: 0.50% Mixture 1 according to the invention, selected from among the examples of mixtures A7 to A9: 10.00%.

[0090] For each of the examples of compositions M20 to M24, mix 1 was mixed with the fat phase either at room temperature (about 25° C.), in the case of the examples of mixtures A10 to A12, or at elevated temperature (60-80° C. or 75-85° C.), in the case of the examples of mixtures A7 to A9. In these embodiments of the compositions, each mix 1 is always first mixed with the respective fat phase using a deflocculator turbine and / or a rotor stator.

[0091] The stability of the examples of compositions M20 to M22 (consisting of emulsions) was monitored over a period of 2 months at room temperature (25° C.), 40° C. and 50° C. The respective viscosities were also monitored over a period of 2 months at room temperature (25° C.). No significant changes were observed. Thus, the mixture 1 of the invention not only allows an excellent redispersibility of the solid particles 2 within the cosmetic and / or dermatological composition, but, moreover, does not have a negative effect on the cosmetic and / or dermatological composition in terms of its stability over time.

[0092] The homogeneity of the examples of compositions M20 to M24 was evaluated by spreading them between two glass plates, spreading them on a grindometer (also called Hegman gauge) at 100 μm and 25 μm, observing them under an optical microscope, and comparing them with examples of compositions M20' to M24' containing the same type (but untreated in the case of solid particles 2) and the same proportions of solid particles 2 (pigments of the examples of mixtures A7 to A12) and other components as the examples of compositions M20 to M24. The pigments of the examples of compositions M20' to M24' were prepared in a fine grinding device (e.g. milling in a 3-cylinder) and dispersed in powder form in the respective liquid fat bodies, without intermediate dispersion in a waxy matrix, to form the examples of compositions M20' to M24'.

[0093] The above observations show that the examples of mixtures M20 to M24, prepared from the examples of mixtures A7 to A12 of the invention, have the same fineness of grinding (particle size, uniformity of dispersion) as the examples of compositions M20' to M24', in which the pigments have been milled, for example in a 3-cylinder, but have not been surface-treated or incorporated in a mixture 1 of the invention intended to be redispersed. In other words, each of the examples of cosmetic compositions M20 to M24, containing a respective mixture 1 according to the invention, each of which comprises solid particles 2, had the same emulsion fineness (particle size, uniformity of dispersion) as if the solid particles had not passed through the mixture 1 of the invention or been surface-treated, but had been finely milled for a long period in a 3-cylinder and directly introduced in powder form into the example of the composition.

[0094] Industrial Applicability Thus, the present invention makes it possible to obtain a mixture 1 containing a large amount of functional agent, and makes the mixture 1 easy to transport, store and handle.

Claims

1. 1. A mixture (1) comprising at least 50% by weight of a functional agent, said mixture (1) also comprising a wax-like matrix (3), said functional agent being dispersed within said wax-like matrix (3), said mixture (1) being solid at room temperature and intended to be dispersed in a cosmetic and / or dermatological composition by fluidization and / or solubilization to incorporate said functional agent into said cosmetic and / or dermatological composition, said functional agent being formed by surface-treated solid particles (2) which have been subjected to a surface treatment which causes a decrease in the absorption capacity of said wax-like matrix (3) by the treated solid particles (2) compared to untreated solid particles of the same type, said solid particles (2) comprising at least organic and / or mineral pigments, organic and / or mineral charges, or a mixture thereof, said surface treatment being configured to increase the hydrophobic properties of said treated solid particles (2) compared to untreated solid particles of the same type.

2. 2. The mixture (1) according to claim 1, characterized in that the surface treatment also makes it possible to increase the oleophilic properties of the treated solid particles (2) compared to untreated solid particles of the same type.

3. 2. The mixture (1) according to claim 1, characterized in that the solid particles (2) are surface-treated with amino acids, alkoxysilanes, fatty acids, phospholipids, hydrogenated olive oil esters, or combinations thereof.

4. 4. A mixture (1) according to any one of claims 1 to 3, characterized in that the surface treatment comprises the grafting of molecules (5) on the surface of each of the particles (2).

5. 5. The mixture (1) according to claim 4, characterized in that the grafted molecules (5) comprise at least siliconized chains, carbonated chains, natural or synthetic polymers, organic molecules, or titanium oxides or silicon oxides.

6. 6. The mixture (1) according to claim 1, characterized in that the waxy matrix (3) comprises at least one natural, mineral and / or synthetic wax, a fatty body solid at room temperature derived from the distillation of one or more natural and / or synthetic oils, a natural and / or synthetic resin, a silicone or silicone polymer wax, or a mixture thereof.

7. 7. The mixture (1) according to any one of claims 1 to 6, wherein the waxy matrix (3) comprises polymethylsilsesquioxane.

8. A mixture (1) according to any one of the preceding claims, characterized in that the solid particles (2) have an average size comprised between 10 nm and 500 μm.

9. The mixture (1) according to claim 8, characterized in that the solid particles (2) have an average size comprised between 100 nm and 100 μm.

10. 10. The mixture (1) according to any one of claims 1 to 9, characterized in that the functional agents are intended to form a physical sunscreen.

11. 11. The mixture (1) according to any one of claims 1 to 10, characterized in that the waxy matrix (3) is liposoluble and / or water-insoluble.

12. 12. The mixture (1) according to any one of claims 1 to 11, characterized in that the waxy matrix (3) is solid at room temperature.

13. A mixture (1) according to any one of the preceding claims, characterized in that the waxy matrix (3) has a melting point and / or softening point comprised in the range from 30 to 150°C.

14. The mixture (1) according to claim 13, characterized in that the waxy matrix (3) has a melting point and / or softening point comprised in the range from 45 to 130°C.

15. A mixture (1) according to any one of claims 1 to 14, characterized in that it is in the form of pellets or sticks (4) obtained by extrusion.

16. 16. The mixture (1) according to any one of claims 1 to 15, characterized in that the functional agent forms at least 70% by weight of the mixture (1).

17. 17. The mixture (1) according to claim 16, characterized in that the functional agent forms at least 80% by weight of the mixture (1).

18. 18. The mixture (1) according to any one of claims 1 to 17, characterized in that the functional agent and the waxy matrix (3) together form at least 95% by weight of the mixture (1).

19. 20. The mixture (1) according to claim 18, characterized in that the functional agent and the waxy matrix (3) together form at least 99% by weight of the mixture (1).

20. 20. The mixture (1) according to any one of claims 1 to 19, characterized in that it does not contain any surfactant.

21. A method for producing a mixture (1) containing at least 50% by weight of a functional agent, the method comprising at least - a heating step (C) of heating the waxy matrix (3) to obtain a fluid matrix (3), a treatment step (T) of solid particles (2), during which the solid particles (2) are subjected to a surface treatment which causes a decrease in the absorption capacity of the fluid matrix (3) by the treated solid particles (2) compared to untreated solid particles (2) of the same type, the treated solid particles (2) forming said functional agent, the surface treatment increasing the hydrophobic properties of the treated solid particles (2) compared to untreated solid particles of the same type, the solid particles (2) comprising at least organic and / or mineral pigments, organic and / or mineral charges or mixtures thereof; - a dispersion step (D) of dispersing said functional agent within said fluid matrix (3); Including, The mixture (1) is solid at room temperature and is intended to be dispersed in a cosmetic and / or dermatological composition by fluidization and / or solubilization to incorporate the functional agent into the cosmetic and / or dermatological composition; A manufacturing method comprising the steps of:

22. 22. The method according to claim 21, characterized in that the solid particles (2) are surface-treated with amino acids, alkoxysilanes, fatty acids, phospholipids, hydrogenated olive oil esters, or combinations thereof.

23. 23. Method according to claim 21 or 22, characterized in that during the heating step (C), the waxy matrix (3) is heated to a temperature equal to or higher than its melting and / or softening point.

24. 24. The method according to any one of claims 21 to 23, characterized in that it further comprises a grinding step (B) of grinding the solid particles (2), intended to reduce the average size of the solid particles (2).

25. 25. The method according to claim 24, characterized in that, upon completion of the grinding step (B), the solid particles (2) have an average size comprised in the range from 10 nm to 500 μm.

26. The method according to claim 25, characterized in that said average size is comprised in the range of 100 nm to 100 μm.

27. 27. The method according to any one of claims 24 to 26, characterized in that the dispersion step (D) at least partially comprises the grinding step (B), such that during at least a part of the grinding step (B), the fluid matrix (3) is mixed with the particles (2).

28. 28. The method according to any one of claims 21 to 27, characterized in that it comprises an extrusion step (E) of extruding said mixture (1) so that said mixture (1) is in the form of granules.

29. The method according to claim 22, characterized in that in the extrusion step (E), the temperature of the mixture (1) is from 60 to 80°C.

30. 30. The method according to any of claims 21 to 29, characterized in that after the dispersing step (D), it comprises a cooling step (F) in which the mixture (1) is cooled to room temperature in order to form a solid.

31. 21. A method for the preparation of a cosmetic and / or dermatological composition, comprising a redispersion step (R) in which a mixture (1) according to any one of claims 1 to 20 is added and then mixed with one or more cosmetically and / or dermatologically acceptable ingredients.

32. 32. Method for producing a cosmetic and / or dermatological composition according to claim 31, characterized in that said redispersion step (R) further comprises a step of solubilizing said mixture (1) by means of one or more of said cosmetically and / or dermatologically acceptable ingredients.

33. 33. Method for producing a cosmetic and / or dermatological composition according to claim 31 or 32, characterized in that the redispersion step (R) further comprises a fluidization step, in which the mixture (1) is heated at least until it becomes fluidized.

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