Bismuth oxyhalide composite material for ultraviolet radiation filtration

Abstract

Bismuth oxyhalide composite material for filtering ultraviolet radiation. The present invention relates to the use, preferably cosmetic, of a composite material P comprising one or more particles of bismuth oxyhalide(s) (a), in particular bismuth oxychloride, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; and at least one chemically inert compound (b), selected from (b)i) organic compounds with a carboxy group, (b)ii) polymers, (b)iii) silicon organic compounds, and (b)iv) inorganic compounds, or mixtures thereof, for filtering UV radiation, preferably UV-B, as well as processes for preparing and composing cosmetic compositions. Figure for abstract: None

Description

Title of the invention: Bismuth oxyhalide composite material for filtering ultraviolet radiation

[0001] The present invention relates to the field of solar protection and more particularly to composite materials of bismuth oxyhalide and chemically inert compound, for their use for filtering ultraviolet radiation.

[0002] The invention also relates to a composition, in particular cosmetic, comprising in particular composite materials of bismuth oxyhalide and chemically inert compound. technical field

[0003] Keratinous materials are exposed to sunlight daily.

[0004] It is known that light radiation with wavelengths between 280 nm and 400 nm allows the human epidermis to tan. However, rays with wavelengths between 280 and 320 nm, called UV-B rays, interfere with the development of a natural tan.

[0005] The negative effects of exposure to ultraviolet light are indeed well known. Prolonged exposure to the sun causes damage, such as sunburn on the skin, and dries out the hair, making it brittle. When the skin is exposed to UV light with a wavelength of approximately 280 nm to approximately 400 nm, long-term damage can lead to serious consequences, such as skin cancer.

[0006] It is also known that UV-A rays, with wavelengths between 320 and 400 nm, penetrate the skin more deeply than UV-B rays. UV-A rays promote rapid and persistent skin pigmentation. Daily exposure to UV-A radiation, even for short periods, under normal conditions, can also lead to the degradation of collagen and elastin fibers, resulting in changes in the skin's microrelief, the appearance of wrinkles, and uneven pigmentation (i.e., brown spots, uneven skin tone, etc.).

[0007] UV light thus contributes to premature skin aging by causing free radicals in the skin that attack DNA, membrane lipids, and proteins. This process is commonly called photoaging.

[0008] Therefore, protection of keratinous materials, especially human ones, such as skin, is essential. Previous technique

[0009] To counter these undesirable effects, it is common practice to formulate anti-UV-A and / or UV-B filters, organic and / or inorganic, in compositions dedicated to providing sun protection.

[0010] These sunscreens are used to protect against UV damage and delay the signs of aging.

[0011] Numerous photoprotective cosmetic compositions for the skin have been proposed to date. They generally contain organic UV filters and / or inorganic UV filters that act according to their own chemical nature and physical properties by absorbing, reflecting, or scattering UV radiation. They generally contain combinations of oil-soluble organic UV filters and / or water-soluble organic UV filters combined with metal oxide pigments.

[0012] As regards conventional organic filters, they must have acceptable cosmetic properties, good solubility in common solvents, particularly oils, and good photostability, both alone and in combination. They must also be colorless or of a color cosmetically acceptable to consumers. These organic filters are generally used in mixtures, and such combinations of filters can limit the range of formulations.

[0013] In addition, photoprotection from inorganic UV filters is today a very important expectation of consumers, as they consider mineral sunscreens safer, especially for sensitive skin.

[0014] Titanium dioxide TiO2 and zinc oxide ZnO are the most common mineral UV filters used.

[0015] However, one of the major drawbacks of such mineral filters lies in the fact that, once applied to the skin, they produce a significant whitening effect on the latter which is cosmetically undesirable and generally not appreciated by users.

[0016] This effect is all the more pronounced when the concentration of mineral filters in the composition is high, which limits their concentration in sunscreen formulations. However, to achieve high sun protection factor (SPF) values ​​(for example, 50), large quantities of these UV filters are necessary.

[0017] To avoid this problem, it would of course be possible to implement reduced quantities of inorganic filter(s), but the resulting compositions, which would certainly lead to films with acceptable transparency on the skin, would then no longer offer adequate protection in the UV range, which greatly limits the interest of such an option.

[0018] Furthermore, the application of large quantities of these UV filters induces, in addition to significant whitening, unpleasant sensations after application to the skin, and In particular, it causes sensations of roughness and dryness on the skin in the case of significant and regular use of the products.

[0019] However, consumers are increasingly seeking products that are not only effective but also easy to apply, provide long-lasting comfort and have satisfactory sensory properties. Description of the invention

[0020] There therefore remains a need to have inorganic UV filters which are effective in photoprotection, and which do not present the disadvantages presented above.

[0021] In particular, there remains a need for inorganic UV filters capable of effectively blocking UV rays, i.e. materials having low transmission of UV rays, particularly in the UV-B and UV-A range, and especially UV-B rays, having high transparency to visible light, i.e. materials having high transmission of rays between 400 and 780 nm, which do not bleach the keratinous materials on which they are applied and having good cosmetic properties.

[0022] In particular, there remains a need for mineral UV filters, distinct from titanium dioxide or zinc oxide, which are just as effective, transparent, do not cause sensations of roughness and dryness on the skin, and are easily formulated, especially at high concentrations.

[0023] The present invention aims precisely to provide new mineral UV filters to meet these expectations. Summary of the invention

[0024] The present invention relates to the use, preferably in cosmetics, of composite materials comprising particles of bismuth oxyhalide, in particular bismuth oxychloride, and at least one or more chemically inert compounds for the filtration of ultraviolet radiation, in particular UV-B radiation, of composite materials and their preparation process.

[0025] Thus, according to a first aspect, the present invention relates to the use, preferably cosmetic, non-therapeutic, of a composite material P comprising: - one or more particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; and - at least one chemically inert compound b), selected from b)i) organic compounds with a carboxy group, b)ii) polymers, b)iii) silicon organic compounds, b)iv) inorganic compounds, and mixtures thereof, to filter UV radiation, preferably UV-B, in particular comprising at least the application on a surface, preferably keratinous materials, of a composition comprising said composite material P, preferably said composite material P comprises, and preferably is made up of, a core comprising, and preferably made up of, bismuth oxyhalide particle(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, and at least one chemically inert compound b), selected from compounds b)i) to b)iv), and mixtures thereof, on the surface of said core.

[0026] According to another aspect of it, the present invention relates to a composition, preferably cosmetic, comprising at least one composite material P comprising, and preferably made up of, one or more particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, preferably constituting the core of said composite material P, and at least one chemically inert compound b) selected from b)i) organic compounds with carboxy group(s), b)ii) polymers, b)iii) silicon organic compounds, b)iv) inorganic compounds, and mixtures thereof, preferably present(s) on the surface of the core of said composite material P.

[0027] According to another aspect of it, the present invention relates to a composite material P comprising, and preferably made up of, one or more particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, preferably constituting the core of said composite material P, and at least one chemically inert compound b), preferably present on the surface of the core of said composite material P, and selected from: b)i) organic compounds with carboxy group(s), in particular linear or branched fatty acids comprising from 8 to 24 carbon atoms, b)ii) polymers, in particular polyethylene glycols, polyethylene amine, polypropylene glycols, polyvinyl alcohols, polyacrylic acids and their salts, polymethacrylic acids and their salts, polymethyl methacrylates, polyvinyl sulfonates,polystyrene sulfonates, polylactic acids and their salts, polycaprolactones, polyglycolic acids, polyacetoacetates, poly(lactic-co-glycolic) acids, celluloses and their derivatives, alginic acids and their salts, carrageenans, starches, pectins, inulins, dextrans and their derivatives, xanthan gum, ulvans, lignosulfonates and their salts, chitins and chitosans, pullulanes, polyvinyl alcohols and polyhydroxystearic acid, and / or their copolymers, b)iii) organic silicon compounds, in particular alkoxysilanes, and especially monoalkoxysilanes, dialkoxysilanes, trialkoxysilanes, their oligomers and their polymerized forms, b)iv) inorganic compounds, in particular inorganic oxides, possibly hydrated, and mixtures thereof.

[0028] Surprisingly, and as can be seen from the examples below, the inventors discovered that the composite materials P according to the invention exhibit exceptional efficiency for filtering ultraviolet radiation, in particular UV-B (280 - 320 nm), and excellent transparency in visible radiation (400 - 780 nm).

[0029] The use of bismuth oxycarbonate particles for filtering ultraviolet radiation was known from document WO 2023 / 117902. However, this document does not describe either bismuth oxyhalides or composite materials capable of filtering UV radiation.

[0030] The composite materials P according to the invention are intended to protect the surfaces on which they are applied from UV-A and / or UV-B radiation, in particular from UV-B radiation.

[0031] In particular, composite materials P are intended to protect keratinous materials, preferably skin and hair, from UV-A and / or UV-B radiation, in particular UV-B radiation, in cosmetic compositions for the fields of sun protection, skincare, hair treatment and makeup.

[0032] For the purposes of this invention, "composite material" means a heterogeneous particulate solid material comprising at least two immiscible components, and whose components are linked by physical and / or chemical interactions.

[0033] For the purposes of this invention, "chemically inert compound" means a compound that does not undergo any chemical reaction or transformation, and in particular does not undergo any oxidation in air and under atmospheric pressure.

[0034] For the purposes of this invention, "high transparency in the visible spectrum" means particles having, in the dispersion medium comprising said particles at a mass fraction of 0.005%, an average transmittance in the 400-780 nm range greater than or equal to 40%, preferably greater than or equal to 45%, and more preferably greater than or equal to 50%.

[0035] For the purposes of this invention, "efficiency for filtering ultraviolet radiation" means particles having an absorbance threshold in the UV range, in the dispersion medium comprising said particles at a mass fraction of 0.005%, greater than 0.22, preferably greater than or equal to 0.23, better still greater than 0.24. even better, above 0.25. The higher the absorbance threshold, the greater the efficiency of filtering UV radiation.

[0036] By "UV-B radiation" is meant radiation in the wavelength range from 280 to 320 nm.

[0037] By "UV-A radiation" is meant radiation in the wavelength range from 320 to 400 nm.

[0038] By visible light, we mean the range of wavelengths from 400 to 780 nm.

[0039] Thus, by "UV filter" in the sense of the present invention, we mean any compound that filters ultraviolet (UV) radiation in the wavelength range from 280 nm to 400 nm.

[0040] By "UV-B filter" is meant any compound that filters ultraviolet (UV) radiation in the wavelength range from 280 nm to 320 nm.

[0041] By "UV-A filter" is meant any compound that filters ultraviolet (UV) radiation in the wavelength range from 320 nm to 400 nm.

[0042] To the inventors' knowledge, this effectiveness of the composite materials according to the invention is characterized for the first time. Composite materials of bismuth oxyhalide, as well as its solvates, such as its hydrates, and chemically inert compounds, have never been proposed or implemented in compositions, particularly cosmetic ones, intended for the effective filtration of UV radiation, especially UV-B radiation.

[0043] The composite materials P according to the invention are in particular intended to protect keratinous materials, in particular skin and hair, from UV radiation, in particular in cosmetic compositions for the fields of sun protection, skincare, hair treatment and makeup.

[0044] The present invention also relates to a method, preferably cosmetic, non-therapeutic for filtering UV-A and / or UV-B radiation, preferably UV-B, comprising at least the application on a surface, preferably keratin materials, of a composition comprising the composite materials P of bismuth oxyhalide a), as well as its solvates, such as its hydrates, and of chemically inert compound(s) b) as defined above and below.

[0045] Another object of the invention is a method for filtering UV-A and / or UV-B radiation, preferably UV-B, comprising at least the application on non-keratin materials of a composition comprising the composite materials P of bismuth oxyhalide a), as well as its solvates, such as its hydrates, and of chemically inert compound(s) b) as defined above and below.

[0046] The present invention also relates to methods for preparing composite materials P according to the invention.

[0047] By "keratinous materials" means in particular the skin, in particular the skin of the body, face, neck, including the scalp, lips, and also keratinous fibers such as hair, eyelashes, eyebrows in particular the skin and / or hair, and preferably the skin.

[0048] The expression "at least one" is equivalent to "one or more".

[0049] The expressions "between ... and ...", "includes from ... to ...", "made up of ... to ...", "varying from ... to ..." and "ranging from ... to ..." should be understood inclusively, unless otherwise specified.

[0050] Other features, variations, and advantages of the compositions according to the invention will become clearer upon reading the description and examples that follow. Brief description of the drawings

[0051] [Fig. 1] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material A at 0.005 wt% in isododecane, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in isododecane.

[0052] [Fig.2] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material B at 0.005 wt% in isododecane, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in isododecane.

[0053] [Fig.3] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material C at 0.005 wt% in isododecane, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in isododecane.

[0054] [Fig.4] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material D at 0.005 wt% in isododecane, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in isododecane.

[0055] [Fig.5] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material E at 0.005 wt% in water, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in water.

[0056] [Fig.6] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material F at 0.005 wt% in water, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in water.

[0057] [Fig.7] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material G at 0.005 wt% in water, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in water.

[0058] [Fig.8] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material H at 0.005 wt% in water, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in water.

[0059] [Fig.9] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material I at 0.005 wt% in water, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in water.

[0060] [Fig. 10] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material J at 0.005 wt% in isododecane, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in isododecane.

[0061] [Fig. 11] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material K at 0.005 wt% in isododecane, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in isododecane.

[0062] [Fig. 12] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material L at 0.005 wt% in isododecane, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in isododecane.

[0063] [Fig. 13] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material M at 0.005 wt% in water, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in water.

[0064] [Fig. 14] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material N at 0.005 wt% in water, compared to the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of bismuth oxychloride particles 1 prepared according to example 1, at 0.005 wt% in water. Detailed description

[0065] The invention relates to a composite material P comprising a) at least one particle of one or more bismuth oxyhalides, in particular bismuth oxychloride, the largest average dimension of said particles being less than 400 nm; and at least one chemically inert compound b), in particular selected from compounds b)i) to b)iv) as described below, and mixtures thereof. Composite material

[0066] As stated previously, the composite material P comprises at least a) a particle of bismuth oxyhalide, in particular bismuth oxychloride, together with its solvates, such as its hydrates, and at least b) a chemically inert compound.

[0067] Preferably, the composite material P comprises a) one or more particles of bismuth oxychloride and b) one or two chemically inert compounds selected from b)i) organic compounds with carboxy group, b)ii) polymers, b)iii) silicon organic compounds, b)iv) inorganic compounds, and mixtures thereof.

[0068] When several chemically inert compounds are used, these can be, for example, several different compounds of the same family b)i), b)ii), b)iii) or b)iv), for example, several different b)i) compounds, or several compounds of different families among the compounds b)i), b)ii), b)iii) or b)iv), for example, a b)i) compound and a b)ii) compound).

[0069] For example, when two chemically inert compounds are used, these can be, for example, two different compounds from the same family b)i), b)ii), b)iii) or b)iv), for example, two different b)i) compounds, or two compounds from different families among the compounds b)i), b)ii), b)iii) or b)iv), for example, a b)i) compound and a b)ii) compound).

[0070] The composite materials P according to the invention can be of various shapes and structures.

[0071] The composite materials P according to the invention can in particular be spherical, cubic, plate-like, cylindrical or tubular.

[0072] The shape of said composite materials P will depend in particular on their preparation process and operating conditions.

[0073] In particular, the composite materials P according to the invention can be in the form of tubes, plates, sheets, rods, spheres, flowers, pompoms, wires, filaments, fibers, needles, cubes or any of their mixtures.

[0074] The composite materials P according to the invention can further aggregate into superstructures. For example, plates, tubes and / or rods can aggregate into spheres, flowers or pom-poms.

[0075] According to a particular embodiment, the composite materials P according to the invention are in the form of spheres.

[0076] According to a particular embodiment, the composite materials P according to the invention are in the form of tubes, plates and / or rods. More preferably, the composite materials P according to the invention are in the form of plates and / or rods.

[0077] Composite materials P in the form of plates or rods or tubes are therefore distinguished in particular from spherical, fibrous shapes, flowers, pompoms, threads, filaments, needles or cubes.

[0078] It is understood that the composite materials P according to the invention can be used in mixture form. When used in mixture form, the composite materials according to the invention can have different morphologies. In particular, the composite materials P according to the invention can be used in a mixture of any proportion of wafers and / or rods and / or tubes.

[0079] According to a preferred embodiment, the composite materials P implemented according to the invention are found mainly or exclusively in the form of plates.

[0080] A composite material P in the form of a "plate" has a length greater than its width and a width greater than its thickness.

[0081] According to a preferred embodiment, the composite materials P are found predominantly or exclusively in the form of rods.

[0082] A composite material P in the form of a “rod” has a solid cylindrical shape and its length L is greater than its diameter d, or has a prism shape whose base is solid polygonal, preferably triangular or hexagonal, and the diameter d of the circle circumscribed about this polygonal base is less than the length L of the prism.

[0083] According to a preferred embodiment, the composite materials P are found mainly or exclusively in the form of tubes.

[0084] A composite material P in the form of a “tube” has a hollow cylindrical shape and its length L is greater than its diameter d.

[0085] By "mostly in the form of plates / sticks / tubes" in the context of the present invention, it is understood that at least 50% by number, in particular at least 70% by number, or even at least 90% by number of the composite materials P are in the form of plates / sticks / tubes respectively.

[0086] Preferably, the average size of the composite materials P is less than 20 pm, more preferably less than 15 pm, even more preferably less than 10 pm.

[0087] The term "average size" refers to the average number of primary particle sizes. Particle sizes can be determined by transmission electron microscopy, for example using a Hitachi HT 7700 microscope, particularly at an accelerating voltage of 100 kV, by scanning electron microscopy, by measuring the specific surface area using the BET method, or by using a laser particle size analyzer. Preferably, particle sizes are determined by transmission electron microscopy, for example using a Hitachi HT 7700 microscope, particularly at an accelerating voltage of 100 kV, or by scanning electron microscopy.

[0088] Preferably, the measurement is made on the smallest individualized or individualizable objects. The average number value can be calculated by analyzing the images obtained using software, such as ImageJ software (CA Schneider, WS Rasband, KW Eliceiri, NIH Image to ImageJ: 25 years of image analysis, Nat. Methods. 9 (2012) 671-675).

[0089] The average dimension is chosen from the average length L, the average width 1, the average thickness e, or the average diameter d.

[0090] By "the average size of the largest dimension" or "the largest average dimension" of composite materials P or particles, we mean the largest average dimension of a surface, such as a face, that can be measured between two diametrically opposite points of an individual particle.

[0091] The "length" L of a composite material P or of a particle is its largest observable dimension on a photograph taken along a direction perpendicular to the plane on which said composite material P or said particle rests.

[0092] The "width" l and "thickness" e of a composite material P or of a particle are the lengths of the major and minor axes, respectively, of the smallest possible ellipse in which the median cross-section of said composite material P or of said particle can be inscribed.

[0093] The “diameter” d of a composite material P or of a particle is the largest observable dimension along a straight line passing through the center of a circle or a sphere.

[0094] The bismuth oxyhalide particle(s) a), in particular bismuth oxychloride, the largest average dimension of which is less than 400 nm, as well as its solvates, such as its hydrates, and the chemically inert compound(s) b) can be arranged in different ways within the composite material P.

[0095] According to one embodiment, the composite material P may have at least one core and at least one coating in layer(s) surrounding said core.

[0096] Thus, they may comprise at least one coating in layer(s) surrounding a chemically different core of said coating.

[0097] The coating can be formed of one or more layers.

[0098] The core of the composite materials P may comprise, and preferably be made of, at least a) one or more particles of bismuth oxyhalide, in particular bismuth oxychloride, the largest average dimension of which is less than 400 nm.

[0099] In particular, the largest average dimension of the core of said particles is less than 400 nm.

[0100] The composite material P may contain particles of bismuth oxyhalide a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, as defined above in the core and / or in the layer or layers forming the coating.

[0101] According to a particular embodiment, the composite material P contains at least one particle of bismuth oxyhalide a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, as defined above in the core.

[0102] According to another particular embodiment, the material contains particles of bismuth oxyhalide a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, as defined above in the coating.

[0103] More preferably, the composite material P comprises, and preferably is made of, a core comprising, and preferably made of, a) at least one or more particles of bismuth oxyhalide(s) a), and in particular of bismuth oxychloride, the largest average dimension of which is less than 400 nm, and one or two chemically inert compounds b) arranged in coating layer(s) of said core.

[0104] According to one embodiment, the chemically inert compound(s) b) may cover all or part of at least one particle of bismuth oxyhalide(s) a), and in particular bismuth oxychloride, as well as its solvates, such as its hydrates.

[0105] In particular, the molar ratio between the number of moles of coating compound(s) and the number of moles of core compound(s) varies from 0.0001 to 20, preferably varies from 0.005 to 10, better from 0.01 to 5, and even more preferably from 0.02 to 3.

[0106] According to a particular embodiment, the composite materials P according to the invention contain at least one layer surrounding the core. Thus, according to a particular embodiment, the composite materials P according to the invention comprise, and preferably are made of, a core comprising, and preferably made of, at least a) one or more particles of bismuth oxyhalide(s), and in particular of bismuth oxychloride, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, said core being covered on the surface, continuously or discontinuously, by a coating comprising at least one chemically inert compound b).

[0107] According to a first variant of the invention, the composite materials P according to the invention comprise a continuous coating, also called bark or shell, namely surrounding the entire surface of the core.

[0108] According to a second embodiment of the invention, the composite materials P according to the invention comprise a discontinuous coating, also called a shell or cladding, namely, discontinuously surrounding the surface of the core. Preferably, from 10% to 90%, more particularly from 10% to 70%, and even more particularly from 30% to 50% of the core surface, is covered by the coating.

[0109] According to one embodiment, the coating is a single-layer coating, that is to say comprising a layer superimposed for all or part on the core, said core comprising, and preferably being made up of, at least a) one or more particles of bismuth oxyhalide(s), and in particular of bismuth oxychloride, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm.

[0110] According to one embodiment, the coating is a multilayer coating, that is to say comprising one or more internal layers and an external layer, in other words several layers superimposed for all or part of which each can be continuous or discontinuous.

[0111] In a multilayer coating, the term "inner layer" means any layer that is not an outer layer. This may be the layer directly superimposed on the core or any intermediate layer between the core and the outer layer.

[0112] In a multilayer coating, the "outer layer" means the layer forming the last layer of the coating that is not contiguous with the core. The outer layer is separated from the core by at least one inner layer. The outer layer has no coating.

[0113] In a multilayer coating formed of two layers, the inner layer is the layer contiguous to the core and the outer layer is the layer contiguous to the inner layer and not contiguous to the core.

[0114] In a multilayer coating formed of more than two layers, the inner layers are the layer adjacent to the core and the intermediate layer(s) between the layer adjacent to the core and the outer layer.

[0115] The internal layer or layers forming the multilayer coating of the composite material P and the single external layer of the composite material P can be formed of identical or different compounds b)

[0116] By identical compounds, it is understood that the compounds have the same chemical composition but may have different morphologies.

[0117] Each layer can be made up of a single compound or a mixture of compounds.

[0118] The layer or layers may in particular extend concentrically with respect to the core.

[0119] In particular, the composite materials P according to the invention have a double layer surrounding the core, in other words an inner layer and an outer layer.

[0120] Preferably, the composite material P comprises, and preferably consists of, a core surrounded totally or partially by one or more coating layers, a layer preferably corresponding to a single chemically inert compound b). According to this embodiment, the core is surrounded by a maximum of five coating layers.

[0121] More particularly, one or more particles of bismuth oxyhalide a), in particular bismuth oxychloride, the largest average dimension of which is less than 400 nm, make up the core and the chemically inert compound(s) b) are arranged in complete and / or partial coating layer(s) around said core.

[0122] According to this preferred embodiment, the chemically inert compounds b) can constitute one or more complete or partial layers around one or more individual particles of one or more bismuth oxyhalide(s) a), and in particular of bismuth oxychloride, the largest average dimension of said particles being less than 400 nm, and / or around aggregates of one or more bismuth oxyhalide(s) a), and in particular of bismuth oxychloride, the largest average dimension of said particles being less than 400 nm.

[0123] According to a preferred embodiment, the composite materials P according to the invention have at least one layer, comprising at least one chemically inert compound b).

[0124] According to a preferred embodiment, the composite materials P according to the invention comprise, and preferably consist of: - a core comprising at least a) at least one particle of bismuth oxyhalide, in particular bismuth oxychloride, together with its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, and - at least one layer continuously or discontinuously surrounding said core and comprising b) at least one chemically inert compound.

[0125] Preferably, the composite materials P according to the invention comprise, and preferably are made of: - a core comprising at least a) at least one particle of bismuth oxyhalide, in particular bismuth oxychloride, together with its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, - a single layer contiguous to said core and comprising b) at least one chemically inert compound.

[0126] According to another preferred embodiment, the composite materials P according to the invention comprise, and preferably consist of:

[0127] - a core comprising at least a) at least one oxyhalide particle of bismuth, in particular bismuth oxychloride, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, and b) at least one chemically inert compound; - at least one layer surrounding said core and comprising b) at least one chemically inert compound.

[0128] According to a particular embodiment, the composite materials P according to the invention comprise, and preferably are made of:

[0129] - a core comprising at least a) at least one oxyhalide particle of bismuth, in particular bismuth oxychloride, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, - an inner layer contiguous to said core comprising b) at least a first chemically inert compound bl), - an outer layer contiguous to said inner layer and comprising at least b) at least a second chemically inert compound b2) different from bl). a) Bismuth oxyhalide particles

[0130] Preferably, the bismuth oxyhalide particle(s) a), in particular bismuth oxychloride, the largest average dimension of which is less than 400 nm, are crystallized in the major natural bismoclite phase and are optionally hydrated.

[0131] According to one embodiment, the bismuth oxyhalide particle(s) a), the largest average dimension of said particles being less than 400 nm, are crystallized and optionally hydrated and have the general formula BiO i+xHal 1+y -zH 2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal designates a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine.

[0132] According to one embodiment, the bismuth oxyhalide particle(s) a) are a mixture of particles of general formula BiO i+xHal 1+y -zH 2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal designates a halogen selected from chlorine, fluorine, iodine and bromine, said mixture comprising at least two particles for which Hal designates two different halides, preferably selected from chlorine, iodine and bromine, and more preferably of two particles of which Hal designates chlorine for one and Hal is selected from iodine and bromine for the other.

[0133] In particular, particles a) are bismuth oxychloride particles of empirical formula BiO 1+x Cl 1+y 'zH 2 O, in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version.

[0134] The bismuth oxyhalide particle(s) a), in particular bismuth oxychloride, may have different morphologies and sizes, and the largest average dimension of said particles is less than 400 nm.

[0135] The shape of the particles of bismuth oxyhalide(s) a), and in particular of bismuth oxychloride, will depend in particular on their preparation process and the operating conditions.

[0136] In particular, the particles of bismuth oxyhalide(s) a), and in particular of bismuth oxychloride, may be in the form of tubes, plates, sheets, rods, spheres, flowers, pompoms, wires, filaments, fibers, needles, cubes, or any mixture thereof.

[0137] The particles a) can further aggregate in the form of superstructures. For example, platelets, tubes and / or rods can aggregate in the form of spheres, flowers or pom-poms.

[0138] According to a preferred embodiment, the bismuth oxyhalide particles (a), and in particular bismuth oxychloride, are in the form of tubes, strips and / or rods. Preferably, the particles (a) are in the form of strips.

[0139] Particles in the form of platelets or rods or tubes are therefore distinguished in particular from spherical, fibrous shapes, flowers, pompoms, threads, filaments, needles or cubes.

[0140] It is understood that the particles a) can be used in the form of a mixture. In particular, the particles a) can be used in a mixture in any proportion of strips and / or rods and / or tubes.

[0141] According to a preferred embodiment, the particles a) used to prepare the composite materials P are found mainly or exclusively in the form of platelets.

[0142] A particle in the form of a "platelet" has a length greater than its width and a width greater than its thickness.

[0143] In particular, when in platelet form, bismuth oxyhalide particles (a), and in particular bismuth oxychloride, as well as its solvates, such as its hydrates, possess: - an average length L ranging from 15 to 400 nm, in particular ranging from 30 to 250 nm, preferably ranging from 50 to 200 nm, more preferably ranging from 70 to 150 nm; - an average width 1 ranging from 10 to 250 nm, in particular ranging from 20 to 200 nm, preferably ranging from 30 to 150 nm, more preferably ranging from 50 to 120 nm; - an average thickness e ranging from 2 to 120 nm, in particular from 5 to 100 nm, preferably from 10 to 80 nm, more preferably from 20 to 50 nm; and - with e < 1 < L.

[0144] According to a preferred embodiment, the particles of bismuth oxyhalide(s) a), and in particular bismuth oxychloride, as well as its solvates, such as its hydrates, are found predominantly or exclusively in the form of rods.

[0145] A particle in the form of a “rod” has a solid cylindrical shape and its length L is greater than its diameter d, or has a prism shape whose base is solid polygonal, preferably triangular or hexagonal, and the diameter d of the circle circumscribed about this polygonal base is less than the length L of the prism.

[0146] In particular, when in rod form, whether cylindrical or prismatic, bismuth oxyhalide particles (a), and in particular bismuth oxychloride, as well as its solvates, such as its hydrates, possess: - an average length L ranging from 30 to 400 nm, in particular ranging from 50 to 250 nm, preferably ranging from 70 to 230 nm, more preferably ranging from 70 to 140 nm; - an average diameter d ranging from 15 to 150 nm, in particular ranging from 20 to 130 nm, preferably ranging from 25 to 120 nm, more preferably ranging from 25 to 100 nm, and even more preferably ranging from 25 to 60 nm; and - with L > d.

[0147] According to a preferred embodiment, the particles of bismuth oxyhalide(s) a), and in particular bismuth oxychloride, as well as its solvates, such as its hydrates, are found predominantly or exclusively in the form of tubes.

[0148] A particle in the form of a “tube” has a hollow cylindrical shape and its length L is greater than its diameter d.

[0149] In particular, when in tube form, bismuth oxyhalide particles (a), and in particular bismuth oxychloride, as well as its solvates, such as its hydrates, possess: - an average length L ranging from 10 to 400 nm, in particular ranging from 20 to 250 nm, preferably ranging from 40 to 200 nm, more preferably ranging from 60 to 200 nm; - an average diameter d ranging from 2 to 30 nm, in particular ranging from 3 to 20 nm, and preferably ranging from 5 to 15 nm; and - with L > d.

[0150] By "mostly in the form of plates / sticks / tubes" in the present invention, it is understood that at least 50% by number, in particular at least 70% by number, or even at least 90% by number of the particles a) are in the form of plates / sticks / tubes respectively. Particle doping a)

[0151] According to a particular embodiment, the particles of bismuth oxyhalide(s) a), and in particular of bismuth oxychloride, according to the invention can be doped.

[0152] In particular, the particles of bismuth oxyhalide(s) a), and in particular of bismuth oxychloride can be doped with one or more chemical elements capable of inserting themselves into the structure or partially substituting for elements already present.

[0153] The particles can be doped via substitutions of all or part of the cations and / or all or part of the anions.

[0154] According to a particular embodiment, the doping relates in part to cations inserted or substituted for bismuth up to a limit of 20% of the bismuth composition.

[0155] According to this variant, the doping rate varies in particular from 0.005% to 15%, preferably from 0.05% to 12%, more preferably from 0.1% to 10%, and even more preferably from 0.5% to 6%.

[0156] In particular, the particles a) can be doped with cations from elements selected from aluminium (Al), silicon (Si), scandium (Sc), titanium (Ti), vanadium (V), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), gallium (Ga), germanium (Ge), yttrium (Y), zirconium (Zr), niobium (Nb), molybdenum (Mo), silver (Ag), indium (In), lanthanum (La), cerium (Ce), tantalum (Ta), tungsten (W) and / or gold (Au).

[0157] Preferably, the particles a) can be doped with cations from elements selected from titanium, vanadium, manganese, iron, copper, zinc, lanthanum, and / or cerium, more preferably from manganese, iron and / or cerium, and even more preferably from manganese or iron.

[0158] According to one embodiment, the particles a) are doped with cations derived from manganese, and the doping rate varies in particular from 0.5% to 2%.

[0159] According to another embodiment, the particles a) are doped with iron-derived cations, and the doping rate varies in particular from 0.5% to 2%.

[0160] According to another particular embodiment, the doping relates in part or in whole to anions inserted or substituted for the halogen group within the limit of 20% of the halogen composition.

[0161] According to this variant, the doping rate varies in particular from 0.001% to 1%, preferably from 0.002% to 0.5%, more preferably from 0.003% to 0.2%, and even more preferably from 0.005% to 0.1%.

[0162] In particular, the particles a) can be doped with anions from elements selected from sulfur (S), and / or with polyatomic anions, in particular selected from the sulfate ion (SO42), the sulfonate ion (S(=O)2-O), the sulfite ion (SO32), the phosphate ion (PO43) and / or the iodate ion (IO3).

[0163] Preferably, the particles according to the invention can be doped with S2, SO32, SO42, more preferably with SO32 and / or SO42, and more preferably with SO42.

[0164] According to another embodiment, the particles a) are doped with the sulfate ion, and the doping rate varies in particular from 0.005% to 0.1%.

[0165] According to another embodiment, the particles a) are doped with cations preferably from elements selected from titanium, vanadium, manganese, iron, copper, zinc, lanthanum, and / or cerium, more preferably selected from manganese, iron and / or cerium, and even more preferably selected from manganese or iron, and with anions preferably from elements selected from sulfur (S), and / or with polyatomic anions, in particular selected from the sulfate ion (SO42), the sulfonate ion (S(=O)2-O), the sulfite ion (SO32), the phosphate ion (PO43) and / or the iodate ion (IO3), more preferably with S2, SO32, SO42, even more preferably with SO32 and / or SO42, and particularly preferably with SO42.

[0166] According to a preferred embodiment, the bismuth oxyhalide(s) particles a), and in particular bismuth oxychloride particles implemented according to the invention are undoped.

[0167] The chemically inert compound(s) b) are preferably present on the surface of the bismuth oxyhalide particle(s) a), and in particular bismuth oxychloride, and may be of different natures described below, b) Chemically inert compounds b)i) Organic compounds with carboxy groups

[0168] The chemically inert compound(s) b) of the composite materials P according to the invention may comprise b)i) one or more hydrophilic, and / or lipophilic and / or amphiphilic molecules, having at least one carboxylic acid function in their chemical composition.

[0169] If one or more organic compounds with a carboxy group b)i) are used, they are preferably chosen from fatty acids, preferably from linear or branched fatty acids comprising 8 to 24 carbon atoms, more preferably from 8 to 20 carbon atoms.

[0170] Preferably, the organic compound(s) with carboxy group(s) b)i) are chosen from stearic acid, oleic acid, lauroyl glutamic acid, capryloyl salicylic acid, 3-[2-(2-methoxyethoxy)ethoxy]propanoic acid, or one of their salts and / or solvates, and mixtures thereof.

[0171] Even more preferably, the organic compound(s) with carboxy groups b)i) are chosen from stearic acid, oleic acid, their salts and / or solvates, and their mixtures.

[0172] According to a particular embodiment, the molar ratio between the number of moles of organic compound(s) with carboxy groups, their salts and / or solvates b)i), and the number of moles of bismuth oxyhalide particles a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, varies from 0.0001 to 20, preferably varies from 0.005 to 10, better from 0.01 to 5, and even more preferably from 0.05 to 3.

[0173] According to one embodiment, the composite material P comprises, and preferably consists of, particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, and of bl) organic compound(s) with carboxy groups, their salts and / or solvates.

[0174] According to this embodiment, the size of the composite materials P is less than 2 pm, more preferably less than 1 pm, even more preferably less than 500 nm.

[0175] According to this embodiment, the composite materials P are preferably mostly in the form of tubes, plates and / or rods, and more preferably in the form of plates. b)ii) Polymers

[0176] The chemically inert compound(s) b) of the composite materials P according to the invention may comprise b)ii) one or more polymers, their salts and / or solvates, preferably nonionic, anionic or cationic organic, more particularly being selected from polyethylene glycols, polyethylene amine, polypropylene glycols, polyvinyl alcohols, polyacrylic acids and their salts, polymethacrylic acids and their salts, polymethyl methacrylates, polyvinyl sulfonates, polystyrene sulfonates, polylactic acids and their salts, polycaprolactones, polyglycolic acids, polyacetoacetates, poly(lactic-co-glycolic) acids, celluloses and their derivatives, alginic acids and their salts, the carrageenans, starches, pectins, inulins, dextrans and their derivatives, xanthan gum, ulvans,lignosulfonates and their salts, chitins and chitosans, pullulanes, polyvinyl alcohols and polyhydroxystearic acid, and / or their copolymers, or mixtures thereof.

[0177] If one or more polymers b)ii) are used, they are preferably selected from: lignosulfonic acid, lignosulfonates, sulfonic polystyrenes, polystyrene sulfonates, anionic derivatives of polyanethol, in particular polyanethol sulfonates, and mixtures thereof; alkyl esters or ethers of polyols, in particular of glycerol; anionic polysaccharides, preferably selected from sulfated polysaccharides, in particular ulvans, dextran sulfates, carrageenans, and mixtures thereof, and carboxylate polysaccharides, in particular alginates; cationic polysaccharides, preferably selected from polysaccharides with amine groups, in particular chitosans; modified polysaccharides, in particular selected from polysaccharide esters, and preferably from pullulan esters;poly(alkylene (C2-C5)imines), and preferably among polyethyleneimines and polypropyleneimines, in particular poly(ethyleneimine); polyamino acids, and preferably among proteins; anionic acyclic polymers bearing carboxylic groups or carboxylates of alkali or alkaline earth metals, such as sodium, and selected by homo or copolymers of (meth)acrylic acid, preferably among sodium polymethacrylates and copolymers of (meth)acrylic acid with alkyl (poly)ether (meth)acrylates, in particular POE / POP (meth)acrylic acid and (meth)acrylate copolymers, and mixtures thereof.

[0178] More preferably, said polymer(s) b)ii) are selected from: carrageenans, chitosans, alginates, in particular of alkali or alkaline earth metals such as sodium alginate, dextrans, in particular of alkali or alkaline earth metals and dextrans sulfates of alkali or alkaline earth metals, such as sodium dextran sulfate, pullulans and their ester derivatives, in particular of carboxylic acid in Ci-C30, preferably in CiO-C2o, such as myristoyl pullulan.

[0179] According to a particular embodiment, the mass ratio between the mass of the bismuth oxyhalide particle(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, and that of the polymer(s) b)ii) varies from 0.01 to 50, preferably from 0.2 to 15, more preferably from 0.3 to 10, and more preferably from 0.5 to 8.5. b)iii) Organic silicon compounds

[0180] The chemically inert compound(s) b) of the composite materials P according to the invention may comprise b)iii) one or more organic silicon compounds, in particular selected from silanes and their polymerized forms, and siloxanes and their polymerized forms (silicones).

[0181] If one or more organic silicon compounds b)iii) are used, they are preferably chosen from silanes having at least one hydrolyzable function.

[0182] In particular, the silicon organic compound(s) b)iii) are selected from alkoxysilanes, and in particular monoalkoxysilanes, dialcoxysilanes, trialcoxysilanes, their oligomers and their polymerized forms.

[0183] In particular, the silicon organic compounds b)iii) are selected from octyltriethoxysilane, dodecyltriethoxysilane, triethoxy(2,4,4-trimethylpentyl)silane, benzyltriethoxysilane, 2-[Methoxy(polyethyleneoxy)propyl]trimethoxysilane (n = 1) and [Hydroxy(polyethyleneoxy)propyl]triethoxysilane (n = 8 - 12), and preferably from triethoxy(2,4,4-trimethylpentyl)silane, benzyltriethoxysilane, 2-[Methoxy(polyethyleneoxy)propyl]trimethoxysilane (n = 1) and [Hydroxy(polyethyleneoxy)propyl]triethoxysilane (n = 8 - 12).

[0184] According to a particular embodiment, the molar ratio between the silicon organic compound(s) b)iii) and the bismuth oxyhalide particle(s) a), in particular bismuth oxychloride, and its solvates, such as its hydrates, varies from 0.0001 to 20, in particular from 0.001 to 5, preferably from 0.01 to 2, and more preferably from 0.05 to 1.

[0185] According to a particular embodiment, the composite material P comprises, and preferably consists of, one or more oxyhalide particle(s) of bismuth a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, and b)iii) of silicon organic compound(s).

[0186] According to this embodiment, the size of the composite materials P is less than 2 pm, more preferably less than 1 pm, even more preferably less than 500 nm. b)iv) Inorganic compounds

[0187] The chemically inert compound(s) b) of the composite materials P according to the invention may comprise b)iv) one or more inorganic compounds distinct from the particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates.

[0188] In particular, they may be amorphous or crystalline forms, hydrated or unhydrated, of oxides or hydroxides or oxyhydroxides of alkaline earth metals, in particular magnesium and calcium, or of transition metals, in particular titanium, manganese, iron, copper, niobium and tantalum, or of lanthanides, in particular cerium, or of post-earth metals, in particular aluminum, zinc, indium and bismuth. Inorganic oxides may also refer to amorphous or crystalline forms, hydrated or unhydrated, of oxides or hydroxides or oxyhydroxides of metalloids.In particular, inorganic compounds b)iv) may be amorphous or crystalline forms, hydrated or non-hydrated, including clays, of oxides or hydroxides or oxy-hydroxides of silicon such as silica SiO2, lithium and / or sodium and / or potassium and / or ammonium and / or calcium and / or magnesium and / or aluminium and / or titanium and / or iron and / or zinc and / or bismuth silicates, aluminium and / or calcium and / or magnesium and / or sodium and / or titanium and / or iron and / or zinc and / or bismuth borosilicates.

[0189] The inorganic compounds b)iv) may be amorphous or crystalline, hydrated or non-hydrated forms of inorganic carbides or sulfides or nitrides, such as silicon carbides, iron, copper and zinc sulfides or such as boron and silicon nitrides.

[0190] In a preferred embodiment of the invention, the composite material P does not contain any inorganic compound b)iv).

[0191] In another preferred embodiment of the invention, the composite material P contains a single inorganic compound b)iv) optionally hydrated, more preferably an inorganic oxide optionally hydrated and even more preferably selected from zinc oxide, titanium oxide, silicon oxide or aluminum oxide optionally hydrated, better selected from silicon oxide or an aluminium oxide possibly hydrated, or better yet a silicon oxide possibly hydrated.

[0192] The molar ratio between the number of moles of inorganic compound(s) b)iv) and the number of moles of one or more particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, varies from 0.0001 to 20, preferably varies from 0.005 to 10, better from 0.01 to 5, and even more preferably from 0.05 to 3.

[0193] When one or more chemically inert compounds of inorganic nature b)iv) are used, the average size of the largest dimension of the composite material P is less than 10 pm, the size of the largest dimension of the bismuth oxyhalide(s) particle a), in particular bismuth oxychloride, being itself less than 400 nm. Preparation process for composite material P

[0194] The composite materials P according to the invention can be obtained by any preparation process known to those skilled in the art, and in particular obtained according to the preparation processes described below.

[0195] In particular, bismuth oxyhalide particles a), in particular bismuth oxychloride, and its solvates, such as its hydrates, are first synthesized and then physical and / or chemical reactions are carried out with the chemically inert compound(s) b) to form the composite materials P in one or more steps.

[0196] Preferably, the particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, are first prepared, then the composite material P is formed with one or more chemically inert compounds b).

[0197] The composite materials P according to the invention can be of various shapes and structures.

[0198] Preferably, the composite materials P comprise, and preferably are made of, a core of bismuth oxyhalide(s) a), in particular bismuth oxychloride, together with its solvates, such as its hydrates, and one or two chemically inert compounds b) on the surface.

[0199] Process for preparing bismuth oxyhalide particles a)

[0200] Bismuth oxyhalide(s) particles (a), in particular bismuth oxychloride, can be obtained by any preparation process known to those skilled in the art.

[0201] Among the commonly used techniques, bismuth oxychloride (doped or undoped) a) can be prepared by hydrolysis of an aqueous solution containing bismuth and chloride ions, itself obtainable, for example, by dissolution of a bismuth precursor soluble in HCl or by dissolving one or more bismuth and chloride precursors soluble in aqueous medium, such as NaCl, KCl, NH4Cl.

[0202] Ultrasound or freeze-drying of such precursor mixtures can also be implemented.

[0203] It is also possible to use more coordinating media that can better control particle growth, such as deep eutectic solvents or glycols and their polymers. For the same reasons, the incorporation of sugars or their derivatives in aqueous media is also employed. Hydrolysis often takes place at temperatures below the boiling point of the solvent or solvent mixture, but the regular use of pressure reactors (solvothermal techniques) can also be considered.

[0204] General process for preparing composite materials P from bismuth oxyhalide particles (a), in particular bismuth oxychloride

[0205] The composite materials P according to the invention can in particular be obtained according to the preparation processes described below.

[0206] In particular, the composite materials P according to the invention as defined above can be obtained in one or more steps.

[0207] Composite materials P can in particular be obtained in a conventional manner by various processes, including contacting particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, with a solution comprising at least one chemically inert compound b) in a solvent or a mixture of solvents e).

[0208] In particular, the process for preparing composite materials P according to the invention involves: - particles of bismuth oxyhalide(s) (a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, of general formula BiO₂ 1+ x H al j +y -zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, the largest average dimension of said particles being less than 400 nm; and - at least one chemically inert compound b) chosen from compounds b)i) to b)iv), and their mixtures, as defined above and / or at least one precursor c) intended to form the chemically inert compound(s) b); - d) possibly one or more additives; and - e) possibly one or more solvents.

[0209] According to a particular embodiment, the process for preparing composite materials P according to the invention may include one or more separation steps.

[0210] According to one embodiment, the process for preparing the PI composite materials according to the invention implements a step consisting of bringing into contact: - at least one particle of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as described above; and - at least one chemically inert compound b) chosen from compounds b)i) to b)iv), and their mixtures, as defined above and / or at least one precursor c) intended to form the chemically inert compound(s) b); - d) possibly one or more additives; and - e) possibly one or more solvents; in the same step.

[0211] According to another embodiment, the process for preparing composite materials P2 according to the invention involves: a) at least one PI composite obtained from: (a) of at least one particle of bismuth oxyhalide(s), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, of general formula BiO₂ 1+ xHal / +y 'zH₂O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, the largest average dimension of said particles being less than 400 nm and said particle(s) constituting the core; and a2) at least one chemically inert compound b) selected from compounds b)i) to b)iv), and their mixtures, as defined above; and / or at least one precursor c) intended to form the chemically inert compound(s) b); d) optionally one or more additives; and e) optionally one or more solvents within the same step; it being understood that said implementation is followed, preferably, by at least one separation step intended to obtain PI composites whose core consists of at least one particle of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, covered in whole or in part by a layer consisting of at least one chemically inert compound b) chosen from compounds b)i) to b)iv), and their mixtures; a2) at least one chemically inert compound b) different from the chemically inert compound(s) used in the preparation of PI and selected from compounds b)i) to b)iv), and mixtures thereof, as defined above, and / or at least one precursor c) intended to form the chemically inert compound(s) b); d) optionally one or more additives; and e) optionally one or more solvents, and a3) one or more separation steps; in order to obtain P2 composite materials comprising, and preferably made of, a core a) covered in whole or in part by two layers made of b) at least one chemically inert compound b) chosen from the compounds b)i) to b)iv) chemically different for each of the two layers.

[0212] According to another embodiment, the process for preparing composite materials according to the invention Pn comprising, and preferably made of, a core a) covered in whole or in part by n superimposed layers, each of which is made of at least one chemically inert compound b) selected from compounds b)i) to b)iv), said compounds b) being chemically different for each of the n layers, employs: [31) P2 composites as described above; and at least one chemically inert compound (b) selected from compounds (b)i) to (b)iv), and mixtures thereof, as defined above and / or at least one precursor (c) intended to form the chemically inert compound(s) (b); (d) optionally one or more additives; and (e) optionally one or more solvents, said implementation being preferably followed by at least one separation step intended to obtain P3 composites coated in whole or in part with an outer layer consisting of at least one chemically inert compound (b) selected from compounds (b)i) to (b)iv), and mixtures thereof; [32) at least one chemically inert compound b) different from the chemically inert compound(s) used in P3 and selected from compounds b)i) to b)iv), and mixtures thereof, as defined above and / or at least one precursor c) intended to form the chemically inert compound(s) b); d) optionally one or more additives; and e) optionally one or more solvents, and [33) possibly one or more separation steps; [34) repeat (n-3) times steps [31) to [33) with the composite Pz obtained in the previous step; [35) one or more separation step(s); in order to obtain composite materials Pn comprising, and preferably made of, a core a) covered in whole or in part by n (n being greater than 2) layers each consisting b) of at least one chemically inert compound b) chosen from the compounds b)i) to b)iv) chemically different between adjacent layers (in other words the compound b) of layer z is chemically different from that of layer (z-1) and of layer (z+1) if layer (z+1) exists).

[0213] In a preferred embodiment of the invention, the chemically inert compound(s) b) are used as such to form the composite material P.

[0214] More preferably, one or two chemically inert compounds b) are used.

[0215] In another preferred version of the invention, one or two chemical precursors c) intended to form the chemically inert compounds b) are used.

[0216] Preferably, a single precursor or two precursors c) are used in two successive steps.

[0217] More preferably, a single precursor c) intended to form a chemically inert compound b) is used.

[0218] In particular, the precursor(s) c) intended to form the chemically inert compound(s) b) are chosen from among the compounds, organic or inorganic, which make it possible to obtain by chemical reaction the chemically inert compounds b) which make up the composite material P.

[0219] In particular, the precursor(s) intended to form the chemically inert compounds b) are denoted c) and may be selected from: - inorganic metallic precursors of chemical elements and their hydrates, in particular solubilized metal oxides, notably sodium silicates or aluminates, halides and their hydrates, nitrates and their hydrates, carbonates and their hydrates, sulfonates and their hydrates, sulfates and their hydrates, phosphates and their hydrates, - organic metallic precursors and their hydrates, in particular alkoxides and their hydrates, carboxylates and their hydrates, lactates and their hydrates, citrates and their hydrates, - esters, in particular fatty acid esters, preferably linear or branched fatty acid esters comprising 8 to 24 carbon atoms, more preferably 8 to 20 carbon atoms, and in particular fatty acid triglycerides, - their mixtures.

[0220] The said precursor(s) c) intended to form the chemically inert compound(s) b) may also be selected from oxidizing precursors, in particular air, water, hydrogen peroxide, peroxides and their hydrates, and / or sulfurizing precursors, in particular hydrogen sulfide, alkali sulfides and their hydrates, and / or nitriding precursors.

[0221] According to a particular embodiment, the process for preparing composite materials P according to the invention uses at least one solvent e).

[0222] The choice of solvent(s) e) may in particular depend on the chemically inert compound(s) b), the precursor(s) of the chemically inert compound(s) c) and the additive(s) d) used in the process.

[0223] In particular, the solvent(s) e) may be chosen from polar or nonpolar, protic or aprotic solvents.

[0224] According to a particular embodiment, the process for preparing composite materials P according to the invention uses at least one additive d).

[0225] In particular, the additive(s) d) may be selected from acids, in particular mineral acids, such as hydrochloric acid or sulfuric acid, and bases, preferably mineral, such as sodium hydroxide or potassium hydroxide.

[0226] According to a particular embodiment, the present invention relates to a process for preparing composite materials P as defined above, comprising at least the steps of: (i) have at least some particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and its solvates, such as its hydrates, of general formula BiO 1+ xHal / +y 'zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z <10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, the largest average dimension of said particles being less than 400 nm, optionally in dispersion in at least one solvent or mixture of solvents el); (ii) have at least one chemically inert compound b) and / or at least one precursor c) of one or more chemically inert compounds b),#possibly in a solvent or mixture of solvents e2); (iii) bring together the particles a) or the dispersion (i), and the chemically inert compounds b) and / or the at least precursor c), optionally in a solvent or mixture of solvents described in (ii) to form the composite material P; (iv) isolate said composite material P.

[0227] Preferably, step (i) is free from the use of solvent el).

[0228] According to one embodiment, the solvent(s) of steps (i) and (ii) may be identical or different.

[0229] In particular, the solvent(s) e1) and / or e2) are chosen from aprotic nonpolar solvents, polar and protic solvents, more preferably from water, alcohols, polyols, and mixtures thereof.

[0230] In particular, when the chemically inert compound(s) b) and / or their precursor(s) c) are hydrophilic and / or amphiphilic, the solvent or mixture of solvents e2) is polar, and when the chemically inert compound(s) b) and / or their precursor(s) c) are hydrophobic and / or amphiphilic, the solvent or mixture of solvents e2) is nonpolar.

[0231] In particular, when the chemically inert compound(s) b) and / or their precursor(s) c) are hydrophilic and / or amphiphilic, the solvent or mixture of solvents e2) is polar and protic, and preferably chosen from water, polyols, and / or mixtures thereof, and most preferably water.

[0232] In particular, when the chemically inert compound(s) b) and / or their precursor(s) c) are hydrophobic and / or amphiphilic, the solvent or mixture of solvents e2) is nonpolar, and preferably chosen from volatile and non-volatile oils or organic solvents.

[0233] Preferably, the mixture (iii) is kept under stirring at atmospheric pressure, in particular for a period of 5 minutes to 24 hours, in particular at a temperature ranging from 20 °C to 200 °C, and in particular in open air or under an inert atmosphere.

[0234] According to a particular embodiment, the process for preparing composite materials P according to the invention may include one or more separation steps, in particular by centrifugation and / or by filtration, in particular by ultrafiltration, and / or by lyophilization and / or by atomization.

[0235] According to a particular embodiment, the process for preparing composite materials P further includes a centrifugation step.

[0236] In particular, according to this embodiment, the process for preparing the composite materials P further comprises: - optionally, a step of adding a solvent or solvent mixtures S in which the chemically inert compound(s) b) is or are not soluble, i.e. the chemically inert compound b) precipitates in the solvent or solvent mixture S, at a temperature ranging from 0 °C to room temperature; - at least one centrifugation step, preferably between 4000 rpm and 14000 rpm, in particular for a duration ranging from 1 minute to 1 hour; and - possibly at least one washing step, preferably with solvent or solvent mixture S; - possibly at least one drying step, in particular oven drying, preferably at a temperature between 50 °C and 100 °C, and especially under vacuum (pressure equal to 10 mmHg), to isolate the composite materials P.

[0237] According to a particular embodiment, the process for preparing composite materials P further includes a filtration step, in particular ultrafiltration.

[0238] In particular, according to this embodiment, the process for preparing the composite materials P further comprises: - possibly, a step of adding a solvent or solvent mixtures S; - a step of separating the composite materials P from the solvent mixture, by filtration, in particular by ultrafiltration, on a membrane preferably with a pore size ranging from 1 nm to 1 pm, even better from 1 to 100 nm; - possibly at least one centrifugation step; - possibly at least one washing step; and - possibly at least one drying step, in particular oven drying, preferably at a temperature between 50 °C and 100 °C, and especially under vacuum (pressure equal to 10 mmHg), to isolate the composite materials P.

[0239] According to a particular embodiment, the process for preparing composite materials P further includes a freeze-drying and / or centrifugation step.

[0240] In particular, according to this embodiment, the process for preparing the composite materials P further includes a freeze-drying step of the mixture, in particular at a temperature ranging from 0 °C to -180 °C, possibly after evaporation of one or more solvents when the reaction medium includes several.

[0241] According to a particular embodiment, the process for preparing composite materials P further includes an atomization step.

[0242] In particular, according to this embodiment, the process for preparing composite materials P further includes a step of atomizing the mixture.

[0243] When the chemically inert compounds b) referred to comprise one or more polymers b)ii), the atomization temperature is preferably less than or equal to the lowest characteristic transition temperature of the polymer(s) b)ii) used in the mixture, the transitions referring to a possible glass transition and / or a possible melting and / or a possible degradation, and greater than the lowest boiling point of the solvent or solvents of the mixture.

[0244] Preferably, the atomization temperature varies from 80 °C to 250 °C, more preferably from 100 °C to 200 °C, and even more preferably from 100 °C to 180 °C.

[0245] According to a particular embodiment, the present invention relates to a one-step preparation process for composite materials P as defined above.

[0246] Thus, according to a particular embodiment, the present invention relates to a process for preparing composite materials P as defined above, comprising the steps of: (Ali) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, and its solvates, such as its hydrates, of general formula BiO 1+ xHal / +y -zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent e), in particular in an amount from 0.05 g / L to 500 g / L; (Al-ii) have a solution of at least one chemically inert compound b) chosen from b)i) to b)iv) and their mixtures as defined above and / or at least one precursor c) intended to form the chemically inert compound(s) b); possibly in mixture with at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (Al-iii) bring said dispersion (Ali) and said solution (Al-ii) into contact to form the composite material P; (Al-iv) isolate said composite material P.

[0247] Said composite material P thus obtained (denoted PI) can in turn be used in place of the particles a) of step (Ali) with a solution (Al-ii)' of at least one chemically inert compound b) chosen from b)i) to b)iv) and their mixtures as defined above and / or at least one precursor c) intended to form the chemically inert compound(s) b); it being understood that the b) and / or the c) are different from those used in the preparation of PI; optionally mixed with at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L to form a composite material P2.

[0248] More generally, a composite material Pn (n greater than or equal to 2) consisting of a core comprising, preferably made of, at least one particle of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and covered totally or partially with n chemically different layers b) can be prepared by implementing; - a composite material P(nl) as a replacement for the particles a) of step (Ali), P(nl) consisting of a core comprising, preferably made of, at least one particle of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and covered totally or partially with (n-1) chemically different layers b); with - a solution (Al-ii)' of at least one chemically inert compound b) chosen from b)i) to b)iv) and their mixtures as defined above and / or at least one precursor c) intended to form the chemically inert compound(s) b); it being understood that the b) and / or the c) are different from those used in the preparation of P(nl); - possibly mixed with at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; to form a composite material Pn.

[0249] According to a particular embodiment, the dispersion medium (Ali) can be heated to reflux, preferably to a temperature of 70 °C.

[0250] According to a particular embodiment, when the solvent or mixture of solvents of step (Ali) contains water, the pH can be adjusted between 5 and 10, for example by adding a base, preferably inorganic, such as alkali or alkaline earth metal hydroxides, like sodium hydroxide.

[0251] According to a particular embodiment, the solution (Al-ii) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (Al-iii).

[0252] According to a particular embodiment, the step molar ratio (Al-iii) chemically inert compound(s) b) and / or one of its salts and / or precursor c) / bismuth oxyhalide a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, varies from 0.0001 to 20, more preferably from 0.01 to 5.

[0253] According to a particular embodiment, step (Al-iii) is carried out under agitation.

[0254] According to a particular embodiment, step (Al-iii) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0255] According to a preferred embodiment, step (Al-iii) is carried out at a temperature above ambient temperature, in particular ranging from 70 °C to 80 °C.

[0256] According to a particular embodiment, the pH in step (Al-iii) is adjusted to 6.5, for example by adding acid, preferably inorganic, such as sulfuric acid.

[0257] According to a particular embodiment, a cooling step can be carried out between steps (Al-iii) and (Al-iv).

[0258] According to a particular embodiment, step (Al-iv) can be carried out by centrifugation.

[0259] According to a particular embodiment, step (Al-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, such as oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0260] According to a particular embodiment, the present invention relates to a two-step preparation process for composite materials P as defined above comprising at least two chemically inert compounds b).

[0261] Thus, according to a particular embodiment, the present invention relates to a process for preparing composite materials P comprising at least two chemically inert compounds b) selected from b)i) to b)iv), and their mixtures, as defined above and / or their precursor(s) c), optionally mixed with at least one solvent e), comprising the steps of: (A-2-i) to have a dispersion of bismuth oxyhalide(s) particles (a), in particular bismuth oxychloride, and its solvates, such as its hydrates, of general formula BiO₂ 1 + xHal / +y -zH₂O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-2-ii) have an aqueous solution of a chemically inert compound b) chosen from b)i) to b)iv), as defined above, preferably an inorganic compound b)iv), or a precursor c), in particular sodium silicate; (A-2-iii) bringing said dispersion (A-2-i) and said solution (A-2-ii) into contact to form particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, and of a chemically inert compound b) selected from b)i) to b)iv) and / or one of its salts, preferably an inorganic compound b)iv), more preferably silica; (A-2-iv) isolate said PI particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, and of a chemically inert compound b) selected from b)i) to b)iv) and / or one of its salts, preferably an inorganic compound b)iv), more preferably silica; (A-2-v) dispersing said PI particles obtained in (A-2-iv) in at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-2-vi) have a solution of at least one chemically inert compound b) chosen from b)i) to b)iv), as defined above and / or one of its salts, preferably a compound b) chosen from organic compounds with a carboxy group b)i) or one of its salts, possibly mixed with at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-2-vii) bring said dispersion (A-2-v) and said solution (A-2-vi) into contact to form the composite material P; (A-2-viii) isolate said composite material P.

[0262] According to a particular embodiment, the present invention relates to a process for preparing in n steps composite materials P as defined above comprising at least n (n being greater than 2) chemically inert compounds b), preferably said n compounds b) each constituting a layer covering in whole or in part a core comprising, and preferably made of, at least one particle of bismuth oxyhalide a), in particular bismuth oxychloride.

[0263] Thus, according to a particular embodiment, the present invention relates to a process for preparing composite materials P comprising at least n (n being greater than 2) chemically inert compounds b) selected from b)i) to b)iv), and their mixtures, as defined above and / or their precursor(s) c), optionally mixed with at least one solvent e), comprising the steps of: (A-3-i) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, and its solvates, such as its hydrates, of general formula BiO₂ 1+ xHal / +y -zH₂O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal designates a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-3-ii) have a solution of at least one chemically inert compound b) chosen from b)i) to b)iv), as defined above, and / or a precursor c); (A-3-iii) bring said dispersion (A-3-i) and said solution (A-3-ii) into contact to form particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, and of a chemically inert compound b) selected from b)i) to b)iv) and / or one of its salts, and / or a precursor c); (A-3-iv) isolate said PI composite particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, and of a chemically inert compound b) selected from b)i) to b)iv) and / or one of its salts; (A-3-v) dispersing said PI particles obtained in (A-3-iv) in at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-3-vi) have a solution of at least one chemically inert compound b) selected from b)i) to b)iv) or mixtures thereof, and / or a precursor c), said solution being chemically different from solution (A-3-ii) with possibly at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-3-vii) to bring said dispersion (A-3-v) and said solution (A-3-vi) into contact to form the composite material P2; (A-3-viii) isolate said composite material P2; repeat (n-2) times steps (A-3-v) to (A-3-viii) it being understood that each step (A-3-ii) is carried out with at least one chemically inert compound b) chosen from b)i) to b)iv), or a precursor c), different from that / those used in the directly preceding step (A-3-ii).

[0264] In particular, the solvent(s) of steps (A-2-i), (A-2-v) and (A-2-vi), or (A-3-i), (A-3-v) and (A-3-vi), may be identical or different, and preferably chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof, and even more preferably from water.

[0265] According to a particular embodiment, the dispersion medium (A-2-i) or (A-3-i) can be heated to reflux, preferably at a temperature less than or equal to 100 °C.

[0266] According to a particular embodiment, step (A-2-iii) or (A-3-iii) is carried out under agitation.

[0267] According to a particular embodiment, step (A-2-iii) or (A-3-iii) is carried out for a period of 15 minutes to 48 hours, preferably from 1 hour to 24 hours, and more preferably from 2 hours to 8 hours.

[0268] According to a preferred embodiment, step (A-2-iii) or (A-3-iii) is carried out at a temperature below 100 °C.

[0269] According to a particular embodiment, step (A-2-iv) or (A-3-iv) can be carried out by centrifugation.

[0270] According to a particular embodiment, step (A-2-iv) or (A-3-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular by oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0271] According to a particular embodiment, the dispersion medium (A-2-v) or (A-3-v) can be heated to reflux, preferably to a temperature of 70 °C.

[0272] According to a particular embodiment, the pH in step (A-2-v) or (A-3-v) is adjusted to a pH ranging from 3 to 10, for example by adding sodium hydroxide or sulfuric acid.

[0273] According to a particular embodiment, the solution (A-2-vi) or (A-3-vi) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (A-2-vii) or (A-3-vii).

[0274] According to a particular embodiment, step (A-2-vii) or (A-3-vii) is carried out under agitation.

[0275] According to a particular embodiment, step (A-2-vii) or (A-3-vii) is carried out for a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0276] According to a preferred embodiment, step (A-2-vii) or (A-3-vii) is carried out at a temperature ranging from 70 °C to 80 °C.

[0277] According to a particular embodiment, the pH in step (A-2-vii) or (A-3-vii) is adjusted to 6.5, for example by adding sulfuric acid.

[0278] According to a particular embodiment, a cooling step can be carried out between steps (A-2-vii) and (A-2-viii) or (A-3-vii) and (A-3-viii).

[0279] According to a particular embodiment, step (A-2-viii) or (A-3-viii) can be carried out by centrifugation.

[0280] According to a particular embodiment, step (A-2-viii) or (A-3-viii) is followed by a washing step, in particular by successive cycles, and possibly by oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0281] According to a particular embodiment, the present invention relates to a process for preparing composite materials P comprising an inert compound b) selected from (b)iv) aluminium oxides, hydroxides and oxyhydroxides and their hydrates, such as alumina, said process comprising the steps of: (A-4-i) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, and its solvates, such as its hydrates, of general formula BiO 1+ xHal / +y -zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent e), in particular in an amount from 0.05 g / L to 500 g / L; (A-4-ii) have a solution of aluminium salts available, in at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-4-iii) bring said dispersion (A-4-i) and said solution (A-4-ii) into contact; (A-4-iii') optionally, isolate said mixture from step (A-4-iii); (A-4-iii”) optionally, subject said mixture of step (A-4-iii) or said mixture possibly isolated from step (A-4-iii') to a calcination step to obtain particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and of aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina; (A-4-iii”') optionally, dispersing said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina (A-4-iii), (A-4-iii') or (A-4-iii”), in at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-4-iv) have a solution of at least one chemically inert compound b) chosen from b)i) to b)iv) as defined above, other than aluminium oxides, hydroxides or oxy-hydroxides or their hydrates, such as alumina, or aluminium salts and / or one of its salts, preferably at least one chemically inert compound b) chosen from b)i), b)ii) or b)iii), possibly mixed with at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-4-v) bring together the mixture, product or dispersion obtained at the end of step (A-4-iii), (A-4-iii'), (A-4-iii”) or (A-4-iii'”), and said solution (A-4-iv) to form the composite material P; (A-4-vi) isolate said composite material P.

[0282] According to a particular embodiment, the calcination step is carried out at a temperature ranging from 200 °C to 400 °C, preferably from 250 °C to 300 °C, in particular for a period ranging from 15 minutes to 2 hours.

[0283] In particular, the solvent(s) of steps (A-4-i), (A-4-ii) and (A-4-iv) may be the same or different, and preferably chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof, and even more preferably from water.

[0284] According to a particular embodiment, said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, are present in the dispersion (A-4-i) at a concentration ranging from 0.05 g / L to 500 g / L, preferably from 10 g / L to 250 g / L, and more preferably from 50 g / L to 150 g / L.

[0285] According to a particular embodiment, the dispersion medium (A-4-i) can be heated to a temperature from 40 °C to 200 °C, preferably from 50 °C to 100 °C, in particular for a period from 1 minute to 24 hours, preferably from 20 minutes to 2 hours.

[0286] According to a particular embodiment, when the solvent or mixture of solvents of step (A-4-i) contains water, the pH can be adjusted between 5 and 10, for example by adding sodium hydroxide.

[0287] According to a preferred embodiment, the aluminium salts of step (A-4-ii) are sodium raluminate.

[0288] According to a particular embodiment, the molar ratio in step (A-4-iii) Al / Bi varies from 0.0001 to 20, more preferably from 0.01 to 5, and even more preferably from 0.05 to 3.

[0289] According to a particular embodiment, the pH in step (A-4-iii) is adjusted to a pH ranging from 6 to 8, for example by adding sodium hydroxide.

[0290] According to a particular embodiment, step (A-4-iii) is carried out under agitation.

[0291] According to a particular embodiment, step (A-4-iii) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0292] According to a preferred embodiment, step (A-4-iii) is carried out at a temperature ranging from 60 °C to 70 °C.

[0293] According to a particular embodiment, the solution (A-4-iv) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (A-4-v).

[0294] According to a particular embodiment, step (A-4-v) is carried out under agitation.

[0295] According to a particular embodiment, step (A-4-v) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0296] According to a preferred embodiment, step (A-4-v) is carried out at a temperature ranging from 70 °C to 80 °C.

[0297] According to a particular embodiment, the pH in step (A-4-v) is adjusted to 6.5, for example by adding sulfuric acid.

[0298] According to a particular embodiment, a cooling step can be carried out between steps (A-4-v) and (A-4-vi).

[0299] According to a particular embodiment, step (A-4-vi) can be carried out by centrifugation.

[0300] According to a particular embodiment, step (A-4-vi) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular by oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0301] Preferably, the process for preparing composite materials P containing b) one or more organic compound(s) with carboxy group(s) b)i) and / or one of their salts according to the invention involves: - particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, of general formula BiO 1+ x Hal / +y -zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal designates a halogen selected from chlorine, fluorine, iodine and bromine, and preferably chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; - one or more organic compound(s) with carboxy group(s) b)i) and / or one of their salts and / or solvates as defined above; - possibly one or more chemically inert compounds b) distinct from organic compounds with a carboxy group b)i) and / or one or more precursors c) intended to form one or more chemically inert compounds distinct from organic compounds with a carboxy group b)i) as defined above; - possibly one or more additives d) as described above; and - possibly one or more solvents e) as described above.

[0302] According to a preferred embodiment, the process for preparing composite materials P uses a single organic compound with a carboxy group b)i), or one of its salts and / or solvates.

[0303] According to a preferred embodiment, the process for preparing composite materials P containing one or more organic compound(s) with carboxy group(s) b)i) and / or one of their salts, involves: - particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, of general formula BiO 1+ x Hal / +y -zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine, and bromine, and preferably chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; and - one or more inert chemical compounds b) chosen from b)i) organic compounds with a carboxy group, and more preferably a single organic compound with a carboxy group, or one of its salts and / or solvates, preferably chosen from sodium stearate; and - does not use chemically inert compounds b) chosen from b)ii), b)iii), b)iv), or mixtures thereof.

[0304] According to another preferred embodiment, the process for preparing the composite materials P according to the invention uses a chemically inert compound b) distinct from the organic compound(s) with carboxy groups b)i) as defined above or one or more precursors intended to form a chemically inert compound b) distinct from the organic compounds with carboxy groups b)i), and preferably chosen from sodium silicate and sodium aluminate.

[0305] According to a particular embodiment, the present invention relates to a process for preparing composite materials P as defined above, comprising the steps of: (Bli) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent, in particular in an amount from 0.05 g / L to 500 g / L; (Bl-ii) have a solution of at least one organic compound with carboxy group(s) b)i) and / or one of its salts, possibly mixed with at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (Bl-iii) bring said dispersion (Bli) and said solution (Bl-ii) into contact to form the composite material P; (Bl-iv) isolate said composite material P.

[0306] In particular, the solvent(s) of steps (Bli) and (Bl-ii) may be the same or different, and preferably chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof, and even more preferably water.

[0307] According to a particular embodiment, the dispersion medium (Bli) can be heated to reflux, preferably to a temperature of 70 °C.

[0308] According to a particular embodiment, when the solvent or mixture of solvents of step (Bli) contains water, the pH can be adjusted between 5 and 10, preferably between 6 and 9, for example by adding a base, preferably inorganic, such as alkali or alkaline earth metal hydroxides, like sodium hydroxide.

[0309] According to a particular embodiment, the solution (Bl-ii) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (Bl-iii).

[0310] According to a particular embodiment, the molar ratio in step (Bl-iii) of organic compound(s) with carboxy group(s) b)i) and / or of one of its salts / bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, varies from 0.0001 to 20, more preferably from 0.01 to 5, and even more preferably from 0.02 to 3.

[0311] According to a particular embodiment, step (Bl-iii) is carried out under agitation.

[0312] According to a particular embodiment, step (Bl-iii) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0313] According to a preferred embodiment, step (Bl-iii) is carried out at a temperature ranging from 70 °C to 80 °C.

[0314] According to a particular embodiment, the pH in step (Bl-iii) is adjusted to 6.5, for example by adding acid, preferably inorganic, such as sulfuric acid.

[0315] According to a particular embodiment, a cooling step can be carried out between steps (Bl-iii) and (Bl-iv).

[0316] According to a particular embodiment, step (Bl-iv) can be carried out by centrifugation.

[0317] According to a particular embodiment, step (Bl-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, such as oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0318] According to a particular embodiment, the present invention relates to a process for preparing composite materials P as defined above, comprising the steps of: (B-2-i) have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent, in particular in an amount from 0.05 g / L to 500 g / L; (B-2-ii) have an aqueous solution of sodium silicate available; (B-2-iii) to bring said dispersion (B-2-i) and said solution (B-2-ii) into contact to form particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and silica; (B-2-iv) isolate said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and silica; (B-2-v) Dispersion of said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and silica (B-2-iv), in at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (B-2-vi) have a solution of at least one organic compound with carboxy group(s) b)i) and / or one of its salts, possibly mixed with at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (B-2-vii) to bring said dispersion (B-2-v) and said solution (B-2-vi) into contact to form the composite material P; (B-2-viii) isolate said composite material P.

[0319] According to a particular embodiment, the preparation process includes a calcination step (B-2-iv') prior to step (B-2-v).

[0320] According to a particular embodiment, the calcination step (B-2-iv') is carried out at a temperature ranging from 200 °C to 400 °C, preferably from 250 °C to 300 °C, in particular for a duration ranging from 15 minutes to 2 hours.

[0321] In particular, the solvent(s) of steps (B-2-i), (B-2-v) and (B-2-vi) may be the same or different, and preferably chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof, and even more preferably from water.

[0322] According to a particular embodiment, the dispersion medium (B-2-i) can be heated to reflux, preferably at a temperature less than or equal to 100 °C.

[0323] According to a particular embodiment, the molar ratio in step (B-2-iii) Si / Bi varies from 0.001 to 10, preferably from 0.01 to 2, and more preferably from 0.1 to 1.

[0324] According to a particular embodiment, the pH in step (B-2-iii) is adjusted to a pH ranging from 3 to 11, in particular from 5 to 8, preferably from 6 to 7, in particular to form silica.

[0325] According to a particular embodiment, step (B-2-iii) is carried out under agitation.

[0326] According to a particular embodiment, step (B-2-iii) is carried out during a duration ranging from 15 minutes to 48 hours, preferably from 1 hour to 24 hours, and more preferably from 2 hours to 8 hours.

[0327] According to a preferred embodiment, step (B-2-iii) is carried out at a temperature below 100 °C.

[0328] According to a particular embodiment, step (B-2-iv) can be carried out by centrifugation.

[0329] According to a particular embodiment, step (B-2-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular drying in an oven, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0330] According to a particular embodiment, the dispersion medium (B-2-v) can be heated to reflux, preferably to a temperature of 70 °C.

[0331] According to a particular embodiment, the pH in step (B-2-v) is adjusted to a pH ranging from 3 to 10, for example by adding sodium hydroxide or sulfuric acid.

[0332] According to a particular embodiment, the solution (B-2-vi) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (B-2-vü).

[0333] According to a particular embodiment, the molar ratio in step (B-2-vii) of organic compound(s) with carboxy group(s) b)i) and / or of one of its salts / particles of bismuth oxyhalide(s) a), in particular of bismuth oxychloride, and of silica, varies from 0.0001 to 20, more preferably from 0.01 to 5, and even more preferably from 0.05 to 3.

[0334] According to a particular embodiment, step (B-2-vii) is carried out under agitation.

[0335] According to a particular embodiment, step (B-2-vii) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0336] According to a preferred embodiment, step (B-2-vii) is carried out at a temperature ranging from 70 °C to 80 °C.

[0337] According to a particular embodiment, the pH in step (B-2-vii) is adjusted to 6.5, for example by adding sulfuric acid.

[0338] According to a particular embodiment, a cooling step can be carried out between steps (B-2-vii) and (B-2-viii).

[0339] According to a particular embodiment, step (B-2-viii) can be carried out by centrifugation.

[0340] According to a particular embodiment, step (B-2-viii) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular by oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0341] According to a particular embodiment, the present invention relates to a process for preparing composite materials P as defined above, comprising the steps of: (B-3-i) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO₂ 1+ xHal / +y -zH₂O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably chlorine, as well as its solvates, such as its hydrates, the largest average size of said particles being less than 400 nm, in at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (B-3-ii) have a solution of aluminium salts available, in at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (B-3-iii) bring said dispersion (B-3-i) and said solution (B-3-ii) into contact; (B-3-iii') optionally, isolate said mixture from step (B-3-iii); (B-3-iii”) optionally, subject said mixture of step (B-3-iii) or said mixture possibly isolated from step (B-3-iii') to a calcination step to obtain particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and of aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina; (B-3-iii' ”) possibly, dispersing said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina (B-3-iii), (B-3-iii') or (B-3-iii”), in at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (B-3-iv) have a solution of at least one organic compound with carboxy group(s) b)i) and / or one of its salts, possibly mixed with at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (B-3-v) bring together the mixture, product or dispersion obtained at the end of step (B-3-iii), (B-3-iii'), (B-3-ii”) or (B-3-iii” '), and said solution (B-3-iv) to form the composite material P; (B-3-vi) isolate said composite material P.

[0342] According to a particular embodiment, the calcination step is carried out at a temperature ranging from 200 °C to 400 °C, preferably from 250 °C to 300 °C, in particular for a period ranging from 15 minutes to 2 hours.

[0343] In particular, the solvent(s) of steps (B-3-i), (B-3-ii) and (B-3-iv) may be the same or different, and preferably chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof, and even more preferably from water.

[0344] According to a particular embodiment, said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, are present in the dispersion (B-3-i) at a concentration ranging from 0.05 g / L to 500 g / L, preferably from 10 g / L to 250 g / L, and more preferably from 50 g / L to 150 g / L.

[0345] According to a particular embodiment, the dispersion medium (B-3-i) can be heated to a temperature ranging from 40 °C to 200 °C, preferably from 50 °C to 100 °C, especially for a period of 1 minute to 24 hours, preferably from 20 minutes to 2 hours.

[0346] According to a particular embodiment, when the solvent or mixture of solvents of step (B-3-i) contains water, the pH can be adjusted between 5 and 10, preferably between 6 and 8, for example by adding sodium hydroxide.

[0347] According to a preferred embodiment, the aluminium salts of step (B-3-ii) are sodium raluminate.

[0348] According to a particular embodiment, the molar ratio in step (B-3-iii) Al / Bi varies from 0.0001 to 20, more preferably from 0.01 to 5, and even more preferably from 0.05 to 3.

[0349] According to a particular embodiment, the pH in step (B-3-iii) is adjusted to a pH ranging from 6 to 8, for example by adding sodium hydroxide.

[0350] According to a particular embodiment, step (B-3-iii) is carried out under agitation.

[0351] According to a particular embodiment, step (B-3-iii) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0352] According to a preferred embodiment, step (B-3-iii) is carried out at a temperature ranging from 60 °C to 70 °C.

[0353] According to a particular embodiment, the solution (B-3-iv) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (B-3-v).

[0354] According to a particular embodiment, the step molar ratio (B-3-v) organic compound(s) with carboxy group(s) b)i) and / or one of its salts / particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, varies from 0.0001 to 20, more preferably from 0.01 to 5, and even more preferably from 0.05 to 3.

[0355] According to a particular embodiment, step (B-3-v) is carried out under agitation.

[0356] According to a particular embodiment, step (B-3-v) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0357] According to a preferred embodiment, step (B-3-v) is carried out at a temperature ranging from 70 °C to 80 °C.

[0358] According to a particular embodiment, the pH in step (B-3-v) is adjusted to 6.5, for example by adding sulfuric acid.

[0359] According to a particular embodiment, a cooling step can be carried out between steps (B-3-v) and (B-3-vi).

[0360] According to a particular embodiment, step (B-3-vi) can be carried out by centrifugation.

[0361] According to a particular embodiment, step (B-3-vi) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular drying in an oven, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0362] Composite materials P comprising at least one organic silicon compound b)iii) can be obtained by reacting one or more alkoxysilanes, preferably amphiphilic, on the inorganic part of the material considered, in particular by a variant of the process described by Zhang et al. (Preparation Method of Silicone Rubber Radiation Protection Nano Composite Material. CN109608890B, 2018) with functionalized alkoxysilanes.

[0363] In particular, the process for preparing composite materials P comprising at least one organic silicon compound (b)iii) involves: - at least one particle of bismuth oxyhalide(s) a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; - one or more silicon organic compound(s) b)iii) and / or one or more precursors c) intended to form one or more silicon organic compounds as defined above; - possibly one or more chemically inert compounds b) distinct from the organic silicon compounds b)iii) as defined above and / or one or more precursors c) intended to form one or more chemically inert compounds b) distinct from the organic silicon compounds b)iii) as defined above; - possibly one or more additives d); and - possibly one or more solvents e).

[0364] According to a preferred embodiment, the process for preparing composite materials P comprising at least one silicon organic compound b)iii) employs a single silicon organic compound or one or more precursors intended to form a single silicon organic compound.

[0365] According to a preferred embodiment, the process for preparing composite materials P comprising at least one silicon organic compound b)iii) further employs a chemically inert compound b) distinct from the silicon organic compound(s) b)iii), as defined above or one or more precursors c) intended to form a chemically inert compound b) distinct from the silicon organic compounds, and preferably selected from sodium silicate and sodium aluminate.

[0366] According to a particular embodiment, the process for preparing composite materials P according to the invention uses at least one solvent.

[0367] The choice of solvent(s) may in particular depend on the precursor(s) and additive(s) used in the process.

[0368] In particular, the solvent or solvents can be chosen from polar or nonpolar, protic or aprotic solvents.

[0369] Preferably, the solvent used is a polar and protic solvent, in particular chosen from water, alcohols, polyols and mixtures thereof.

[0370] According to a particular embodiment, the process for preparing composite materials P according to the invention uses at least one additive.

[0371] In particular, the additive(s) may be chosen from acids, especially mineral acids, such as hydrochloric acid or sulfuric acid, and bases, preferably mineral, such as sodium hydroxide or potassium hydroxide. They may also be chosen from oxidants, reducers and / or any reagent necessary for the precipitation of the species and / or their adhesion.

[0372] The silicon organic compound(s) b)iii) as defined above may be used pure or in mixtures. The silicon organic compound(s) b)iii) as defined above may be used in solution in a solvent or without a solvent.

[0373] According to a particular embodiment, the present invention relates to a process for preparing composite materials P as defined above, comprising the steps of: (Cli) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent, in particular in an amount from 0.05 g / L to 500 g / L; (Cl-ii) have a solution of at least one organic silicon compound b)iii), possibly mixed with at least one solvent; (Cl-iii) bring said dispersion (Cli) and said solution (Cl-ii) into contact to form the composite material P; (Cl-iv) isolate said composite material P.

[0374] In particular, the solvent(s) of steps (Cli) and (Cl-ii) may be identical or different.

[0375] In particular, the solvent or solvents of step (Cli) is chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof, and even more preferably from water.

[0376] In particular, the solvent(s) of step (Cl-ii) is chosen from among polar and protic solvents, more preferably from among alcohols, and even more preferably is an alcohol corresponding to the alkoxide radical of the organic silicon compound b)iii).

[0377] According to a particular embodiment, the dispersion medium (Cli) can be heated to reflux, preferably at a temperature less than or equal to 80 °C.

[0378] According to a particular embodiment, the solution (Cl-ii) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (Cl-iii).

[0379] According to a particular embodiment, the step molar ratio (Cl-iii) silicon organic compound(s) b)iii) / bismuth oxyhalide(s) a), in particular bismuth oxychloride, and its solvates, such as its hydrates, varies from 0.0001 to 20, preferably from 0.005 to 10, better from 0.01 to 5, and even more preferably from 0.05 to 3.

[0380] According to a particular embodiment, the pH in step (Cl-iii) is adjusted between 1.5 and 5, preferably between 2 and 4.

[0381] According to a particular embodiment, the pH in step (Cl-iii) is adjusted between 8 and 12, preferably between 9 and 11.

[0382] According to a particular embodiment, step (Cl-iii) is carried out under stirring.

[0383] According to a preferred embodiment, step (Cl-iii) is carried out with heating of the reaction medium, preferably at a temperature ranging from 70 °C to 80 °C.

[0384] According to a particular embodiment, step (Cl-iii) is carried out for a duration ranging from 15 minutes to 48 hours, preferably from 1 hour to 24 hours, and more preferably from 2 hours to 8 hours.

[0385] According to a particular embodiment, a cooling step can be carried out between steps (Cl-iii) and (Cl-iv).

[0386] According to a particular embodiment, step (Cl-iv) can be carried out by centrifugation.

[0387] According to a particular embodiment, step (Cl-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, such as oven drying, for example at a temperature ranging from 40 °C to 100 °C and possibly under vacuum (pressure less than 100 mbar).

[0388] According to a particular embodiment, the present invention relates to a process for preparing composite materials P comprising at least one organic silicon compound b)iii) as described above, comprising the steps of: (C-2-i) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent, in particular in an amount from 0.05 g / L to 500 g / L; (C-2-ii) have an aqueous solution of sodium silicate available; (C-2-iii) to bring said dispersion (C-2-i) and said solution (C-2-ii) into contact to form particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and silica; (C-2-iv) isolate said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and silica; (C-2-v) Dispersion of said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and silica (C-2-iv), in at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (C-2-vi) have a solution of at least one organic silicon compound b)iii), possibly mixed with at least one solvent; (C-2-vii) to bring said dispersion (C-2-v) and said solution (C-2-vi) into contact to form the composite material P; (C-2-viii) isolate said composite material P.

[0389] According to a particular embodiment, the preparation process includes a calcination step (C-2-iv') prior to step (C-2-v).

[0390] According to a particular embodiment, the calcination step (C-2-iv') is carried out at a temperature ranging from 200 °C to 400 °C, preferably from 250 °C to 300 °C, in particular for a period ranging from 15 minutes to 2 hours.

[0391] In particular, the solvent(s) of steps (C-2-i), (C-2-v) and (C-2-vi) may be identical or different, and preferably chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof.

[0392] According to a particular embodiment, the dispersion medium (C-2-i) can be heated to reflux, preferably at a temperature less than or equal to 100 °C.

[0393] According to a particular embodiment, the molar ratio in step (C-2-iii) Si / Bi varies from 0.001 to 10, preferably from 0.01 to 2, and more preferably from 0.1 to 1.

[0394] According to a particular embodiment, the pH in step (C-2-iii) is adjusted to a pH ranging from 3 to 11, in particular from 5 to 8, preferably from 6 to 7.

[0395] According to a particular embodiment, step (C-2-iii) is carried out under agitation.

[0396] According to a particular embodiment, step (C-2-iii) is carried out for a period of 15 minutes to 48 hours, preferably from 1 hour to 24 hours, and more preferably from 2 hours to 8 hours.

[0397] According to a preferred embodiment, step (C-2-iii) is carried out at a temperature below 100 °C.

[0398] According to a particular embodiment, step (C-2-iv) can be carried out by centrifugation.

[0399] According to a particular embodiment, step (C-2-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, such as oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0400] According to a particular embodiment, the dispersion medium (C-2-v) can be heated to reflux, preferably at a temperature less than or equal to 80 °C.

[0401] According to a particular embodiment, the solution (C-2-vi) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (C-2-vü).

[0402] According to a particular embodiment, the molar ratio in step (C-2-vii) of silicon organic compound(s) b)iii) / particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and silica, varies from 0.0001 to 20, preferably varies from 0.005 to 10, better from 0.01 to 5, and even more preferably from 0.05 to 3.

[0403] According to a particular embodiment, the pH in step (C-2-vii) is adjusted between 1.5 and 5, preferably between 2 and 4.

[0404] According to a particular embodiment, the pH in step (C-2-vii) is adjusted between 8 and 12, preferably between 9 and 11.

[0405] According to a particular embodiment, step (C-2-vii) is carried out under agitation.

[0406] According to a preferred embodiment, step (C-2-vii) is carried out at a temperature ranging from 70°C to 80°C.

[0407] According to a particular embodiment, step (C-2-vii) is carried out for a period of 15 minutes to 48 hours, preferably from 1 hour to 24 hours, and more preferably from 2 hours to 8 hours.

[0408] According to a particular embodiment, a cooling step can be carried out between steps (C-2-vii) and (C-2-viii).

[0409] According to a particular embodiment, step (C-2-viii) can be carried out by centrifugation.

[0410] According to a particular embodiment, step (C-2-viii) is followed by a washing step, in particular by successive cycles, and optionally by drying, in particular drying in an oven, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0411] According to a particular embodiment, the present invention relates to a process for preparing composite materials P comprising at least one organic silicon compound b)iii) comprising the steps of: (C-3-i) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, together with its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent, in particular in an amount from 0.05 g / L to 500 g / L; (C-3-ii) have a solution of a soluble and / or hydrated form of alumina, such as a solution of aluminium salts, in at least one solvent; (C-3-iii) bring said dispersion (C-3-i) and said solution (C-3-ii) into contact; (C-3-iii') optionally, isolate said mixture from step (C-3-iii); (C-3-iii”) optionally, subject 1 said mixture from step (C-3-iii) or said mixture possibly isolated from step (C-3-iii') to a calcination step to obtain particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and of aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina; (C-3-iii' ”) possibly, dispersing said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina (C-3-iii), (C-3-iii') or (C-3-iii”), in at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (C-3-iv) have a solution of at least one organic silicon compound b)iii), possibly mixed with at least one solvent; (C-3-v) bring together the mixture, product or dispersion obtained at the end of step (C-3-iii), (C-3-iii'), (C-3-iii”), or (C-3-iii'”) and said solution (C-3-iv) to form the composite material P; (C-3-vi) isolate said composite material P.

[0412] According to a particular embodiment, the calcination step is carried out at a temperature ranging from 200 °C to 400 °C, preferably from 250 °C to 300 °C, in particular for a period ranging from 15 minutes to 12 hours.

[0413] In particular, the solvent(s) of steps (C-3-i), (C-3-ii) and (C-3-iv) may be the same or different, and preferably chosen from polar solvents and protics, more preferentially among water, alcohols, polyols and their mixtures.

[0414] According to a particular embodiment, said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, are present in the dispersion (C-3-i) at a concentration ranging from 0.05 g / L to 500 g / L, preferably from 10 g / L to 250 g / L, and more preferably from 50 g / L to 150 g / L.

[0415] According to a particular embodiment, the dispersion medium (C-3-i) can be heated to a temperature from 40 °C to 200 °C, preferably from 50 °C to 100 °C, in particular for a period from 1 minute to 24 hours, preferably from 20 minutes to 2 hours.

[0416] According to a particular embodiment, when the solvent or mixture of solvents of step (C-3-i) contains water, the pH can be adjusted between 5 and 10, preferably between 6 and 8, for example by adding at least one base, preferably mineral, such as alkali or alkaline earth metal hydroxides, in particular the pH can be adjusted with sodium hydroxide.

[0417] According to a preferred embodiment, the aluminium salts of step (C-3-ii) are sodium raluminate.

[0418] According to a particular embodiment, the molar ratio in step (C-3-iii) Al / Bi varies from 0.0001 to 20, preferably varies from 0.005 to 10, better from 0.01 to 5, and even more preferably from 0.05 to 3.

[0419] According to a particular embodiment, the pH in step (C-3-iii) is adjusted to a pH 6.5, for example by adding at least one acid, preferably mineral, such as sulfuric acid.

[0420] According to a particular embodiment, step (C-3-iii) is carried out under agitation.

[0421] According to a particular embodiment, step (C-3-iii) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0422] According to a preferred embodiment, step (C-3-iii) is carried out at a temperature ranging from 60 °C to 70 °C.

[0423] According to a particular embodiment, step (C-3-iv) is preceded by a washing step, in particular by successive cycles, and possibly by drying, in particular by oven drying, for example at a temperature of 50°C, and possibly under vacuum (pressure less than 100 mbar).

[0424] According to a particular embodiment, the solution (C-3-iv) can be heated to reflux, preferably to a temperature of 80 °C, before mixing in step (C-3-v).

[0425] According to a particular embodiment, the dispersion medium (C-3-v) can be heated to reflux, preferably at a temperature less than or equal to 80 °C.

[0426] According to a particular embodiment, the step molar ratio (C-3-v) silicon organic compound(s) b)iii) / bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, and its solvates, such as its hydrates, varies from 0.0001 to 20, preferably from 0.005 to 10, better from 0.01 to 5, and even more preferably from 0.05 to 3.

[0427] According to a particular embodiment, the pH in step (C-3-v) is adjusted between 1.5 and 5, preferably between 2 and 4.

[0428] According to a particular embodiment, the pH in step (C-3-v) is adjusted between 8 and 12, preferably between 9 and 11.

[0429] According to a particular embodiment, step (C-3-v) is carried out under stirring.

[0430] According to a preferred embodiment, step (C-3-v) is carried out at a temperature ranging from 70°C to 80°C.

[0431] According to a particular embodiment, step (C-3-v) is carried out for a duration ranging from 15 minutes to 48 hours, preferably from 1 hour to 24 hours, and more preferably from 2 hours to 8 hours.

[0432] According to a particular embodiment, a cooling step can be carried out between steps (C-3-v) and (C-3-vi).

[0433] According to a particular embodiment, step (C-3-vi) can be carried out by centrifugation.

[0434] According to a particular embodiment, step (C-3-vi) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular by oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0435] The process for preparing composite materials P comprising at least one chemically inert compound b) selected from inorganic compounds b)iv) involves: - at least one particle of bismuth oxyhalide a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH 2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; - one or more inorganic compound(s) b) chosen from the inorganic compounds b)iv) and / or one or more precursors c) intended to form one or more inorganic compounds b)iv) as defined above; - possibly one or more inert compounds b) distinct from the inorganic compounds b)iv) as defined above and / or one or more precursors c) intended to form one or more chemically inert compounds b) distinct from inorganic compounds b)iv) as defined above; - possibly one or more additives d); and - possibly one or more solvents e).

[0436] According to a preferred embodiment, the process for preparing the composite material P comprising at least one chemically inert compound b) selected from the inorganic compounds b)iv) employs particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, pre-formed to form the core of said composite material P.

[0437] According to a preferred embodiment, the composite material P obtained by the preparation process according to the invention contains a single inorganic compound b)iv) to constitute the bark of the composite materials P, and preferably the inorganic compound b)iv) is chosen from silica and aluminum hydroxide.

[0438] According to these embodiments, the composite materials P comprising at least one chemically inert compound b) chosen from the inorganic compounds b)iv) can be obtained by precipitation onto the core consisting of one or more particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride: - of one or more silicon tetraalkoxides, preferably C2-C4, such as tetraethyl orthosilicate or tetrapropyl orthosilicate, notably by a process derived from the so-called Stôber method (Controlled Growth of Monodisperse Silica Spheres in the Micron Size Range. J. Colloid Interface Sci. 1968, 26 (1), 62-69); - and / or sodium silicate (Brinker, CJ; Scherer, GW Sol-Gel Science: The Physics and Chemistry of Sol-Gel Processing; Elsevier, 1990) in aqueous medium by analogy with the process described by Pfluecker et al. (Nanoparticulate UV Protectant With Silicon Dioxide Coating. US 8758501 B2, 2014) on titanium dioxide; - and / or sodium aluminate.

[0439] According to another embodiment, the process for preparing composite materials P comprising at least one chemically inert compound b) selected from the inorganic compounds b)iv) employs pre-formed particles of at least one inorganic compound b)iv), preferably silica, to form the core of said composite material P, and the bark is made up of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates.

[0440] According to this embodiment, the composite materials P can in particular be obtained by precipitation of bismuth nitrate pentahydrate using ammonium carbonate on the core of inorganic compound(s) b)iv).

[0441] According to a particular embodiment, the present invention relates to a process for preparing composite materials P as defined above, comprising the steps of: (Dli) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent, in particular in an amount from 0.05 g / L to 500 g / L; (Dl-ii) have an aqueous solution of sodium silicate c), in particular in a molar ratio Si / Bi between 0.001 and 10, preferably between 0.01 and 2, and even more preferably between 0.1 and 1; (Dl-iii) bring said dispersion (Dli) and said solution (Dl-ii) into contact to form the composite material P; (Dl-iv) isolate said composite material P.

[0442] In particular, the solvent(s) of step (Dli) are chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof, and even more preferably from water.

[0443] According to a particular embodiment, the dispersion medium (Dli) can be heated to reflux, preferably at a temperature less than or equal to 100 °C.

[0444] According to a particular embodiment, the solution (Dl-ii) can be heated to reflux, preferably to a temperature of 100 °C, before mixing in step (Dl-iii).

[0445] According to a particular embodiment, the aqueous sodium silicate solution c) is in an amount ranging from 0.05 g / L to 500 g / L.

[0446] According to a particular embodiment, the pH in step (Dl-iii) is adjusted to a pH ranging from 3 to 11, in particular from 5 to 8, preferably from 6 to 7, in particular to form silica.

[0447] According to a particular embodiment, step (Dl-iii) is carried out for a duration ranging from 15 minutes to 48 hours, preferably from 1 hour to 24 hours, and more preferably from 2 hours to 8 hours.

[0448] According to a particular embodiment, a cooling step can be carried out between steps (Dl-iii) and (Dl-iv).

[0449] According to a particular embodiment, step (Dl-iv) can be carried out by centrifugation.

[0450] According to a particular embodiment, step (Dl-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular by oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0451] According to a particular embodiment, the present invention relates to a process for preparing composite materials P comprising at least one chemically inert compound b) selected from inorganic compounds b)iv) comprising the steps of: (D-2-i) have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent, in particular in an amount from 0.05 g / L to 500 g / L; (D-2-i') add a basic aqueous solution, preferably aqueous ammonia, to said dispersion (D-2-i); (D-2-ii) have a solution of at least one silicon tetraalkoxide c); (D-2-iii) bring said dispersion (D-2-i') and said solution (D-2-ii) into contact to form the composite material P; (D-2-iv) isolate said composite material P.

[0452] In particular, the solvent(s) of step (D-2-i) are chosen from polar and protic solvents, more preferably from alcohols, and even more preferably is an alcohol corresponding to the alkoxide group of silicon tetraalkoxide c) or corresponding to one of the alkoxide groups in the case of using a mixture of silicon tetraalkoxides c).

[0453] According to a particular embodiment, the dispersion medium (D-2-i) can be heated until reflux of the medium, preferably at a temperature between 50 °C and 70 °C.

[0454] According to a particular embodiment, the medium is maintained at this temperature throughout the duration of the reaction.

[0455] According to a particular embodiment, the molar ratio in step (D-2-iii) ammonia / silicon varies from 0.005 to 50, more preferably from 0.1 to 5.

[0456] According to a particular embodiment, the molar ratio in step (D-2-iii) Si / Bi varies from 0.001 to 2, more preferably from 0.01 to 1.5, and even more preferably from 0.1 to 1.

[0457] According to a particular embodiment, step (D-2-iii) is carried out for a period of 15 minutes to 48 hours, preferably 30 minutes to 24 hours, and more preferably 1 hour to 8 hours.

[0458] According to a particular embodiment, a cooling step can be carried out between steps (D-2-iii) and (D-2-iv).

[0459] According to a particular embodiment, step (D-2-iv) can be carried out by centrifugation.

[0460] According to a particular embodiment, step (D-2-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular by oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0461] According to a particular embodiment, the present invention relates to a process for preparing composite materials P comprising at least one chemically inert compound b) selected from inorganic compounds iv) comprising the steps of: (D-3-i) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, together with its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent, in particular in an amount from 0.05 g / L to 500 g / L; (D-3-ii) have a solution of a soluble and / or hydrated form of alumina, such as a solution of aluminium salts, in at least one solvent; (D-3-iii) bring said dispersion (D-3-i) and said solution (D-3-ii) into contact; (D-3-iii') optionally isolate said mixture from step (D-3-iii); (D-3-iii”) possibly subject said mixture of step (D-3-iii) or said mixture possibly isolated from step (D-3-iii') to a calcination step to obtain particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and of aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina; (D-3-iv) isolate said composite material P.

[0462] According to a particular embodiment, the calcination step is carried out at a temperature ranging from 200 °C to 400 °C, preferably from 250 °C to 300 °C, in particular for a period ranging from 15 minutes to 2 hours.

[0463] In particular, the solvent(s) of steps (D-3-i) and (D-3-ii) may be the same or different, and preferably chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof.

[0464] According to a particular embodiment, said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, as well as its solvates, such as its hydrates, are present in the dispersion (D-3-i) at a concentration ranging from 0.05 g / L to 500 g / L, preferably from 10 g / L to 250 g / L, and more preferably from 50 g / L to 150 g / L.

[0465] According to a particular embodiment, the dispersion medium (D-3-i) can be heated to a temperature from 40 °C to 200 °C, preferably from 50 °C to 100 °C, in particular for a period from 1 minute to 24 hours, preferably from 20 minutes to 2 hours.

[0466] According to a particular embodiment, when the solvent or mixture of solvents of step (D-3-i) contains water, the pH can be adjusted between 5 and 10, preferably between 6 and 8, for example by adding at least one base, preferably mineral, such as alkali or alkaline earth metal hydroxides, in particular the pH can be adjusted with sodium hydroxide.

[0467] According to a preferred embodiment, the aluminium salts of step (D-3-ii) are sodium raluminate.

[0468] According to a particular embodiment, the molar ratio in step (D-3-iii) Al / Bi varies from 0.0001 to 20, preferably varies from 0.005 to 10, better from 0.01 to 5, and even more preferably from 0.05 to 3.

[0469] According to a particular embodiment, the pH in step (D-3-iii) is adjusted to a pH of 6.5, for example by adding at least one acid, preferably mineral, such as sulfuric acid.

[0470] According to a particular embodiment, step (D-3-iii) is carried out under agitation.

[0471] According to a particular embodiment, step (D-3-iii) is carried out during a duration ranging from 1 minute to 24 hours, preferably from 20 minutes to 8 hours.

[0472] According to a preferred embodiment, step (D-3-iii) is carried out at a temperature ranging from 60 °C to 70 °C.

[0473] According to a particular embodiment, a cooling step can be carried out between steps (D-3-iii) and (D-3-iv).

[0474] According to a particular embodiment, step (D-3-iv) can be carried out by centrifugation.

[0475] According to a particular embodiment, step (D-3-iv) is followed by a washing step, in particular by successive cycles, and possibly by drying, in particular by oven drying, for example at a temperature ranging from 40 °C to 100 °C, and possibly under vacuum (pressure less than 100 mbar).

[0476] The process for preparing composite materials P comprising at least one inert compound b) selected from polymers b)ii) involves: - particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH 2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; - one or more polymers b)ii) as defined above; - possibly one or more chemically inert compounds b) distinct from polymers b)ii) as defined above and / or one or more precursors c) intended to form one or more chemically inert compounds distinct from polymers b) as defined above; - possibly one or more additives d); and - possibly one or more solvents e).

[0477] According to a particular embodiment, the process for preparing composite materials P according to the invention may include one or more separation steps.

[0478] In particular, the precursor(s) c) intended to form the chemically inert compound(s) are chosen from among the compounds, organic or inorganic, which make it possible to obtain by chemical reaction the chemically inert compounds b) which make up the composite material P.

[0479] According to a preferred embodiment, the process for preparing composite materials P comprising at least one chemically inert compound b) selected from polymers b)ii) employs a single chemically inert compound b), this being a polymer b)ii) as defined above.

[0480] According to a preferred embodiment, the process for preparing composite materials P comprising at least one chemically inert compound b) selected from polymers b)ii) involves: - at least one polymer b)ii), and - at least one chemically inert compound b) distinct from polymers b)ii) or one or more precursors intended to form a chemically inert compound distinct from polymers b)ii), and preferably selected from sodium silicate and sodium aluminate.

[0481] According to a particular embodiment, the process for preparing composite materials P according to the invention uses at least one solvent e).

[0482] The choice of solvent(s) may in particular depend on the precursor(s) and additive(s) used in the process.

[0483] In particular, the solvent(s) e) may be chosen from polar or nonpolar, protic or aprotic solvents.

[0484] According to a particular embodiment, the process for preparing composite materials P according to the invention uses at least one additive d).

[0485] In particular, the additive(s) d) may be selected from acids, in particular mineral acids, such as hydrochloric acid or sulfuric acid, and bases, preferably mineral, such as sodium hydroxide or potassium hydroxide.

[0486] According to a particular embodiment, the process for preparing composite materials P comprising at least one chemically inert compound b) selected from polymers b)ii) comprises at least the steps of: (Eli) have at least one particle of bismuth oxyhalide a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH2 O in which -0.3 < x < 0.3 ; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, optionally in dispersion in at least one solvent or mixture of solvents; (El-ii) have a solution of at least one polymer b)ii), possibly in a solvent or mixture of solvents e); (El-iii) bring said at least one particle of bismuth oxyhalide a), in particular bismuth oxychloride, or dispersion (Eli), into contact with said solution (El-ii) to form the composite material P; (El-iv) isolate said composite material P.

[0487] Preferably, step (Eli) is solvent-free.

[0488] According to one embodiment, the solvent(s) of steps (Eli) and (El-ii) may be identical or different.

[0489] In particular, the solvent(s) of (Eli) and (El-ii) are chosen from aprotic nonpolar solvents, polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof.

[0490] In particular, when the polymer(s) b)ii) are hydrophilic and / or amphiphilic the solvent or mixture of solvents (El-ii) is polar, and when the polymer(s) b)ii) are hydrophobic and / or amphiphilic, the solvent or mixture of solvents (El-ii) is nonpolar.

[0491] In particular, when the polymer(s) b)ii) are hydrophilic and / or amphiphilic, the solvent or mixture of solvents (El-ii) is polar and protic, and preferably chosen from water, polyols, and / or mixtures thereof, and most preferably is water.

[0492] In particular, when the polymer(s) b)ii) are hydrophobic and / or amphiphilic, the solvent or mixture of solvents (El-ii) is nonpolar, and preferably chosen from volatile and non-volatile oils, or organic solvents.

[0493] Preferably, the mixture (El-iii) is kept under stirring at atmospheric pressure for a period of 5 minutes to 24 hours, in particular at a temperature ranging from 20 °C to 200 °C, and especially in open air or under an inert atmosphere.

[0494] According to a particular embodiment, the process for preparing composite materials P comprising at least one chemically inert compound b) selected from polymers b)ii) may include one or more separation steps, in particular by centrifugation and / or by filtration, in particular ultrafiltration, and / or by lyophilization and / or by atomization.

[0495] According to a particular embodiment, the process for preparing composite materials P further includes a centrifugation step.

[0496] In particular, according to this embodiment, the process for preparing composite materials P comprising at least one chemically inert compound b) selected from polymers b)ii) further comprises: - optionally, a step of adding a solvent or solvent mixtures S in which the polymer(s) b)ii) is or are not soluble, i.e. the polymer b)ii) precipitates in the solvent or solvent mixture S, at a temperature ranging from 0 °C to room temperature; - at least one centrifugation step, preferably between 4000 rpm and 14000 rpm, in particular for a duration ranging from 1 minute to 1 hour; and - possibly at least one washing step, preferably with solvent or solvent mixture S; - possibly at least one drying step, in particular oven drying, preferably at a temperature of 50 °C, and especially under vacuum (pressure equal to 10 mmHg), to isolate the composite materials P.

[0497] According to a particular embodiment, the process for preparing composite materials P comprising at least one chemically inert compound b) selected from polymers b)ii) further comprises a filtration step, in particular ultrafiltration.

[0498] In particular, according to this embodiment, the process for preparing composite materials P comprising at least one chemically inert compound b) selected from polymers b)ii) further comprises: - optionally, a step of adding a solvent or solvent mixtures S, - a step of separating the composite materials P from the solvent mixture, by filtration, in particular by ultrafiltration, on a membrane preferably with a pore size ranging from 1 nm to 1 pm, even better from 1 to 100 nm, - optionally at least one centrifugation step, - optionally at least one washing step, and - possibly at least one drying step, in particular oven drying, preferably at a temperature of 50 °C, and especially under vacuum (pressure equal to 10 mmHg), to isolate the composite materials P.

[0499] According to a particular embodiment, the process for preparing composite materials P further includes a freeze-drying step.

[0500] In particular, according to this embodiment, the process for preparing the composite materials P further includes a freeze-drying step of the mixture, in particular at a temperature ranging from 0 °C to -180 °C, possibly after evaporation of one or more solvents when the reaction medium includes several.

[0501] According to a particular embodiment, the process for preparing composite materials P further includes an atomization step.

[0502] In particular, according to this embodiment, the process for preparing the composite materials P further comprises a step of atomizing the mixture. In particular, the atomization temperature is preferably lower than or equal to the lowest characteristic transition temperature of polymer b)ii) or of all the polymers b)ii) constituting the mixture, the transitions referring to a possible glass transition and / or a possible melting and / or a possible degradation, and higher than the lowest boiling point of the solvent or solvents of the mixture.

[0503] Preferably, the atomization temperature varies from 80 °C to 250 °C, more preferably from 100 °C to 200 °C, and even more preferably from 100 °C to 180 °C.

[0504] According to a particular embodiment, the composite materials P comprising the bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, and the chemically inert compound(s) b), are prepared without prior isolation of the bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, formed.

[0505] According to this embodiment, the synthesis steps are similar to those described above, but occur simultaneously rather than successively.

[0506] In particular, BiOCl / Fe2O3 composite materials prepared from metallic bismuth spheres and FeCl3, or from bismuth nitrate pentahydrate and FeCl3, are prepared according to this embodiment.

[0507] According to this embodiment, with direct preparation of the composite materials P, the process for preparing the composite materials P as defined above comprises at least the steps of: (Fi) have at least one precursor (f) of bismuth oxyhalide(s) particles (a), in particular bismuth oxychloride, of general formula BiO₂ → 1 + xH₂O + y - zH₂O, where -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably chlorine, the largest average dimension of said particles being less than 400 nm, possibly in dispersion in at least one solvent or mixture of solvents el)#; (F-ii) have at least one chemically inert compound b) and / or at least one precursor of one or more chemically inert compounds c),#possibly in a solvent or mixture of solvents e2); (F-iii) bring together the particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, or the dispersion (Fi) and the chemically inert compounds b) and / or precursors of one or more chemically inert compounds c), possibly in solution described in (F-ii), to form the composite material P; (F-iv) isolate said composite material P.

[0508] In particular, the precursors f) may be elemental bismuth or one or more bismuth(III) complexes, such as bismuth nitrate and its hydrated forms, bismuth citrate and its hydrated forms, bismuth sulfate and its hydrated forms, and bismuth chloride and its hydrated forms. Composition

[0509] Composite materials P comprising one or more bismuth oxyhalide particles a) and one or more chemically inert compound(s) b) according to the invention can in particular be used in a composition, preferably in a cosmetic composition.

[0510] Thus, the present invention also relates to a composition, in particular a cosmetic one, comprising at least: (i) at least one composite material P comprising one or more bismuth oxyhalide particles (a) and one or more chemically inert compound(s) (b), as defined above; ii) at least one aqueous phase and / or at least one oily phase; and iii) possibly at least one compound selected from: 1) separate UV filters of composite materials P; 2) coloring materials; 3) cosmetic active ingredients for the care of keratin materials; 4) surfactants; 5) thickeners; 6) dispersing polymers; and mixtures thereof.

[0511] Said composite materials P may be present in the composition, preferably cosmetic, in a content ranging from 0.5% to 50% by weight, preferably from 1% to 35% by weight, even better from 2% to 30% by weight, relative to the total weight of the composition. Aqueous phase

[0512] A composition, in particular a cosmetic one, according to the invention may comprise at least one aqueous phase.

[0513] The aqueous phase may include water and optionally a water-soluble solvent.

[0514] In the present invention, "water-soluble solvent" means a compound that is liquid at room temperature and miscible with water (miscibility in water greater than 50% by weight at 25°C and atmospheric pressure).

[0515] The water-soluble solvents usable in a composition according to the invention may also be volatile.

[0516] Among the water-soluble solvents that can be used in a composition according to the invention, we can mention in particular lower monoalcohols having 1 to 5 carbon atoms, such as ethanol and isopropanol, C2-C32 polyols, C3 and C4 ketones and C2-C4 aldehydes.

[0517] Among the water-soluble solvents that can be used in a composition according to the invention, polyols may be mentioned in particular. For the purposes of this invention, "polyol" means any organic molecule comprising at least two free hydroxyl groups.

[0518] A polyol suitable for the invention may be an alkyl-type compound, linear, branched or cyclic, saturated or unsaturated, having on the alkyl chain at least two -OH functions, in particular at least three -OH functions, and more particularly at least four -OH functions.

[0519] Polyols advantageously suitable for the formulation of a composition according to the present invention are those having in particular from 2 to 32 carbon atoms, preferably from 3 to 16 carbon atoms.

[0520] Preferably, the polyol can be chosen for example from pentaerythritol, trimethylolpropane, caprylyl glycol, glycerol, polyglycerols, such as glycerol oligomers like diglycerol, polyethylene glycols, and mixtures thereof. Fatty phase

[0521] A composition, in particular a cosmetic one, according to the invention may further comprise at least one oily phase, in particular an oily phase.

[0522] For the purposes of the invention, "fat phase" means a phase comprising at least one fat and all the fat-soluble and lipophilic ingredients used for the formulation of the compositions of the invention.

[0523] Preferably, the oily phase comprises at least one oil, in particular a cosmetic oil.

[0524] By "oil" is meant a non-aqueous compound, immiscible with water, liquid at room temperature (25 °C) and atmospheric pressure (760 mm Hg).

[0525] The oily phase may comprise at least one volatile or non-volatile hydrocarbon oil and / or a fat, preferably a volatile and / or non-volatile silicone oil and / or a volatile and / or non-volatile fluorinated oil.

[0526] Examples of non-volatile hydrocarbon oils include vegetable hydrocarbon oils, synthetic ethers with 10 to 40 carbon atoms, linear or branched hydrocarbons of mineral or synthetic origin, synthetic esters, fatty alcohols liquid at room temperature with a branched and / or unsaturated carbon chain with 12 to 26 carbon atoms, higher C12-C22 fatty acids, carbonates, and mixtures thereof.

[0527] Examples of volatile hydrocarbon oils include hydrocarbon oils having 8 to 16 carbon atoms.

[0528] Non-volatile silicone oils may be selected, in particular, from among non-volatile polydimethylsiloxanes (PDMS) and phenyl silicones. Examples of volatile silicone oils include, for example, volatile linear or cyclic silicone oils.

[0529] Fluorinated volatile oils, such as nonafluoromethoxybutane, decafluoropentane, tetradecafluorohexane, dodecafluoropentane and mixtures thereof, may also be used.

[0530] The oil phase may further comprise, mixed with or solubilized in the oil, other fatty substances. Another fatty substance that may be present in the oil phase may be, for example, a fatty acid, a wax, a gum, a paste-like compound, or mixtures thereof. 1) Additional UV filters

[0531] According to a particular embodiment, a composition according to the invention comprises 1) at least one UV filter separate from the composite materials P, required according to the invention and defined above.

[0532] By "UV filter distinct from composite materials P", for the purposes of the present invention, means any UV filter whose chemical nature differs from that of the composite materials comprising the particles of bismuth oxyhalide(s), and in particular of bismuth oxychloride, required according to the invention and defined above.

[0533] The composite materials P of bismuth oxyhalide(s), and in particular of bismuth oxychloride, according to the invention, can therefore be used alone or in association with 1) other UV filters, in particular chosen from organic and / or inorganic UV filters.

[0534] Thus, the composition, preferably cosmetic, may also contain one or more additional UV filters chosen from among hydrophilic, lipophilic or insoluble organic UV filters and / or mineral UV filters.

[0535] By "hydrophilic UV filter" is meant any organic or inorganic compound that filters UV radiation and is capable of being completely dissolved in molecular form in a liquid aqueous phase or of being in colloidal suspension (for example in micellar form) in a liquid aqueous phase.

[0536] By "lipophilic UV filter" is meant any organic or inorganic compound that filters UV radiation and is capable of being completely dissolved in molecular form in a liquid oil phase or of being in colloidal suspension (for example in micellar form) in a liquid oil phase.

[0537] By "insoluble UV filter" is meant any organic or inorganic compound that filters UV radiation and has a solubility in water of less than 0.5% by weight and a solubility of less than 0.5% by weight in most organic solvents such as paraffin oil, fatty alcohol benzoates, and fatty acid triglycerides, for example, Miglyol 812® marketed by Dynamit Nobel. This solubility, measured at 70 °C, is defined as the amount of product in solution in the solvent at equilibrium with an excess of suspended solids after returning to room temperature. It can easily be determined in the laboratory.

[0538] Complementary organic UV filters are selected in particular from: - cinnamic compounds, in particular Ethylhexyl Methoxycinnamate, - anthranilate compounds, in particular Menthyl anthranilate, - salicylic compounds, in particular Homosalate and Ethylhexyl Salicylate, - dibenzoylmethane compounds, in particular Butyl Methoxydibenzoylmethane, - benzylidene camphor compounds, in particular 3-Benzylidene camphor, 4-Methylbenzylidene camphor, Benzylidene Camphor Sulfonic Acid and Terephthalylidene Dicamphor Sulfonic Acid, - benzophenone compounds, in particular oxybenzone and n-hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate, - [3,[3-diphenylacrylate] compounds, in particular octocrylene, - triazine compounds, in particular Phenylene Bis-Diphenyl triazine, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Ethylhexyl Triazone and Diethylhexyl Butamido Triazone, - Benzotriazole compounds, in particular Drometrizole Trisiloxane, - Benzalmalonate compounds, in particular those cited in US patent 5624663, especially Polysilicone-15, - Benzimidazole derivatives, in particular Phenylbenzimidazole Sulfonic Acid, - Imidazoline compounds, in particular Ethylhexyl Dimethoxybenzylidene Dioxoimidazoline Propionate, - bis-benzoazolyl compounds, as described in patents EP 0669323 and US 2463264, in particular Disodium Phenyl Dibenzimidazole Tetra-sulfonate, - para-aminobenzoic compounds, in particular PABA, Ethylhexyl Dimethyl PABA and PEG-25 PABA, - methylene bis-(hydroxyphenyl benzotriazole) compounds, as described in US applications 5237071, US 5166355, GB 2303549, DE 19726184 and EP 0893119, in particular Methylene bis-Benzotriazolyl Tetramethylbutylphenol, - benzoxazole compounds, as described in patent applications EP 0832642, EP 1027883, EP 1300137 and DE 10162844, in particular 2,4-bis-[5-l(dimethylpropyl)benzoxazol-2-yl-(4-phenyl)-imino]-6-(2-ethylhexyl)-imino-l,3,5-triazine or 2,4-bis-{ [4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-l,3,5-triazine (INCI name: Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine; BEMT), - filter polymers and filter silicones, such as those described in particular in application WO 93 / 04665, - α-alkylstyrene derived dimers, such as those described in patent application DE 19855649, - 4,4-diarylbutadiene compounds, as described in applications EP 0967200, DE 19746654, DE 19755649, EP 1008586, EP 1133980 and EP 0133981, in particular 1,1-dicarboxy (2,2'-dimethyl-propyl)-4,4-diphenylbutadiene, and - mixtures thereof.

[0539] Inorganic UV filters are generally mineral UV filters, in particular selected from metal oxides.

[0540] The metal oxides may be selected in particular from titanium, zinc, iron, zirconium, cerium oxides, and mixtures thereof. Preferably, they are different from bismuth oxyhalides, and in particular from bismuth oxychloride.

[0541] Metal oxide particles may be coated or uncoated.

[0542] The coated particles are more particularly coated titanium oxides of silica, of silica and iron oxide, of silica and alumina, of alumina, of alumina and aluminum stearate, of silica, alumina and alginic acid, of alumina and aluminum laurate, of iron oxide and iron stearate, of zinc oxide and zinc stearate, of silica and alumina treated with silicone, of silica, alumina, aluminum stearate treated with silicone, of silica treated with silicone, of alumina treated with silicone, of triethanolamine, of stearic acid, of sodium hexametaphosphate, or of TiO2 treated with octyl trimethylsilane, of TiO2 treated with polydimethylsiloxane, of TiO2 anatase / rutile treated with polydimethylhydrogenosiloxane, TiO2 coated with triethylhexanoin, aluminum stearate and alumina, TiO2 coated with aluminum stearate, alumina and silicone, lauroyl lysine coated TiO2, or C9.15 fluoroalcohol phosphate and aluminum hydroxide coated TiO2.

[0543] Metal oxides may optionally be doped.

[0544] In this respect, we can cite TiO2 particles doped with at least one transition metal, such as iron, zinc, manganese, and more particularly manganese.

[0545] The doped particles may be in the form of a dispersion, preferably an oily dispersion. The oil present in the oily dispersion is preferably selected from triglycerides, including those of capric / caprylic acids. The oily dispersion of titanium dioxide particles may further comprise one or more dispersing agents, for example, a sorbitan ester or a polyoxyalkylated fatty acid and glycerol ester. A particular example is the oily dispersion of manganese-doped TiO2 particles in capric / caprylic acid triglyceride in the presence of tri-PPG-3 myristylether citrate and polyglyceryl-3-polyricinoleate and sorbitan isostearate.

[0546] We can also mention mixtures of metal oxides, in particular titanium dioxide and cerium dioxide, including the equal weight mixture of titanium dioxide and cerium dioxide coated with silica, as well as the mixture of titanium dioxide and zinc dioxide coated with alumina, silica and silicone or coated with alumina, silica and glycerin. 2) Coloring agents

[0547] According to a particular embodiment, a composition according to the invention comprises 2) at least one coloring material.

[0548] Generally speaking, a "colouring matter" means any compound capable of colouring a composition, that is to say, which absorbs in the visible spectrum, in particular so as to appear to the human eye as a colour, such as yellow, orange, red, violet, blue or green.

[0549] Preferably, a composition according to the invention comprises at least one pigment.

[0550] By "pigments" we mean white or colored, mineral particles or organic, insoluble in hydrophilic and lipophilic liquid phases, intended to color and / or opacify the composition containing them. More specifically, pigments are poorly or not at all soluble in hydroalcoholic media.

[0551] The pigments that may be used are chosen in particular from among the organic and / or mineral pigments known to the art, especially those described in Kirk-Othmer's Encyclopedia of Chemical Technology and in Ullmann's Encyclopedia of Industrial Chemistry (Ullmann's Encyclopedia of Industrial Chemistry, "Pigment Organics", 2005, Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim). 10.1002 / 14356007.a20 371 and ibid, “Pigments, Inorganic, 1. General” 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheiml0.1002 / 14356007.a20_243.pub3).

[0552] These pigments may be in the form of a powder or pigment paste. They may be coated or uncoated.

[0553] Pigments can, for example, be chosen from mineral pigments, organic pigments, lacquers, special effect pigments such as mother-of-pearl or glitter, and mixtures thereof.

[0554] The pigment may be a mineral pigment. By mineral pigment is meant any pigment that meets the definition in the Ullmann Encyclopedia in the chapter on inorganic pigments. Examples of mineral pigments useful in the present invention include iron or chromium oxides, manganese violet, ultramarine blue, chromium hydrate, ferric blue, and titanium oxide.

[0555] The pigment may be an organic pigment.

[0556] By organic pigment, we mean any pigment that meets the definition in the Ullmann encyclopedia in the chapter on organic pigment.

[0557] The colouring material(s) may be present in a composition according to the invention in a content ranging from 0.001% to 10% by weight, preferably from 0.005% to 5% by weight, relative to the total weight of the composition.

[0558] According to a particular embodiment of the invention, the quantity of different pigments of the composite materials P varies from 0.5% up to 40%, and preferably from 1% to 20% by weight, relative to the total weight of the composition of the invention comprising them. 3) Cosmetic active ingredient

[0559] According to a particular embodiment, a composition according to the invention comprises 3) at least one cosmetic active ingredient for the care of keratinous materials, preferably for skin care.

[0560] In particular, the cosmetic active may be at least one hydrophilic active and / or one lipophilic active, preferably hydrophilic.

[0561] The term “hydrophilic active” means a water-soluble or water-dispersible active capable of forming hydrogen bonds.

[0562] Examples of cosmetic active ingredients include moisturizing agents, depigmenting agents, desquamating agents, humectants, anti-aging agents, mattifying agents, healing agents, antibacterial agents, vitamins and their derivatives or precursors, antioxidant compounds, free radical scavengers, anti-polluting agents, self-tanning agents, anti-glycation agents, soothing agents, deodorizing agents, essential oils, NO-synthase inhibitors, agents that stimulate the synthesis of dermal or epidermal macromolecules and / or prevent their degradation, and agents that stimulate fibroblast proliferation. agents stimulating keratinocyte proliferation, muscle relaxants, cooling agents, tightening agents, pro-pigmenting agents, keratolytic agents, slimming agents, agents acting on the energy metabolism of cells, insect repellents, substance P or CRGP antagonists, anti-hair loss agents, and mixtures thereof.

[0563] Such assets may be present in a composition according to the invention in a content ranging from 0.05% to 10% by weight, preferably from 1.0% to 8.0% by weight, relative to the total weight of the composition. 4) Surfactant

[0564] According to a particular embodiment, a composition according to the invention comprises 4) at least one surfactant.

[0565] By "surfactant" we mean a "surface agent" or "surfactant" which is a compound capable of modifying the surface tension between two surfaces, surfactants are amphiphilic molecules, i.e. which have two parts of different polarity, one lipophilic and nonpolar and the other hydrophilic and polar.

[0566] When there are several surfactants this implies that the surfactants are chemically different and / or of different molar weight, and in this case are found in a mixture.

[0567] The surfactant(s) may be selected from nonionic, anionic, cationic, amphoteric or zwitterionic surfactants, and mixtures thereof. Reference may be made to the document "Encyclopedia of Chemical Technology, KIRK-OTHMER", Volume 22, pp. 333-432, 3rd edition, 1979, WILEY, for the definition of the properties and emulsifying functions of surfactants, in particular pp. 347-377 of that reference, for anionic, amphoteric and nonionic surfactants.

[0568] Among non-ionic surfactants, one can cite, alone or in mixtures, fatty alcohols, alpha-diols and alkylphenols, these three types of compounds being polyethoxylated, polypropoxylated and / or polyglycerolated, and having an aliphatic chain comprising, for example, 6 to 30 carbon atoms, in particular comprising 10 to 22 carbon atoms, the number of ethylene oxide or propylene oxide groups being able to range in particular from 2 to 200, in particular from 10 to 100, and the number of glycerol groups being able to range in particular from 2 to 200, in particular from 5 to 100, more particularly from 8 to 20, such as 10.We can also mention ethylene oxide (EO) and propylene oxide (PO) copolymers, ethylene oxide and propylene oxide condensates on fatty alcohols, polyethoxylated fatty amides preferably having 2 to 30 moles EO, polyglycerol fatty amides having on average 1 to 5 glycerol groups, and in particular 1.5 to 4, oxyethylenated sorbitan fatty acid esters having 2 to 200 moles EO, in particular 10 to 100 EO, sucrose fatty acid esters, polyethylene glycol fatty acid esters, the . alkylpolyglycosides, N-alkyl glucamine derivatives, amine oxides, such as alkyl (C10-C14)amine oxides or N-acylaminopropylmorpholine oxides in particular, (poly)ethoxylated fatty alcohols, glycerolized fatty alcohols, alkylpolyglycosides, in particular oxyethylenated sorbitan fatty acid mono- and diesters having 2 to 200 moles OE, in particular 10 to 100 OE, such as propylene glycol stearate having 10 to 30 OE such as 20 OE; glyceryl mono distearate / polyethylene glycol stearate (100 OE).

[0569] By "fatty chain" is meant a hydrocarbon chain comprising 6 to 30 carbon atoms, preferably 8 to 24 carbon atoms, linear or branched, saturated or unsaturated, such as stearyl, oleyl, lauryl.

[0570] As regards alkyl polyglycosides, these compounds are well known and can be more particularly represented by the following general formula: RiO-(R2O)t (G)v (III) Formula (III) in which: - R represents a linear or branched alkyl and / or alkenyl radical comprising approximately 8 to 24 carbon atoms, an alkylphenyl radical whose linear or branched alkyl radical comprises 8 to 24 carbon atoms, preferably a saturated or unsaturated, linear or branched alkyl radical comprising 8 to 18 carbon atoms; - R2 represents an alkylene radical containing approximately 2 to 4 carbon atoms; - G represents a sugar motif containing 5 to 6 carbon atoms, preferably glucose, fructose or galactose, better glucose; -1 denotes an integer between 0 and 10 inclusive, preferably between 0 and 4, preferably between 0 and 4, better still 0; and - v denotes an integer between 1 and 15 inclusive, preferably from 1 to 4, and better from 1 to 2.

[0571] Compounds of formula (III) are notably represented by the products sold by COGNIS under the names PLANTAREN® (600 CS / U, 1200 and 2000) or PLANTACARE® (818, 1200 and 2000). Products sold by SEPPIC under the names TRITON CG 110 (or ORAMIX CG 110) and TRITON CG 312 (or ORAMIX® NS 10), products sold by BASF under the name LUTENSOL GD 70, or those sold by CHEM Y under the name AGIO LK may also be used.

[0572] One can also use, for example, the C8 / Ci6 Alkyl polyglucoside 1.4 in aqueous solution at 53% marketed by COGNIS under the reference PLANTACARE® 818 UP.

[0573] As regards mono- or polyglycerol surfactants, they preferably comprise on average from 1 to 40 glycerol groups, more particularly from 5 to 30 glycerol groups, such as 10. Monoglycerol or polyglycerol surfactants are preferably chosen from compounds with the following formulas: RO[CH2CH(CH2OH)O]mH, RO[CH2CH(OH)CH2O]mH, or RO[CH(CH2OH)CH2O]mH, formulas in which: - R represents a saturated or unsaturated, linear or branched hydrocarbon radical, comprising 8 to 40 carbon atoms, and preferably 10 to 30 carbon atoms; - m is a number between 1 and 30, preferably between 1 and 10, more particularly from 1.5 to 6. R may optionally include heteroatoms such as oxygen and nitrogen. In particular, R may optionally include one or more hydroxyl and / or ether and / or amide groups. R preferably denotes alkyl and / or alkenyl radicals of the form C10-C20, possibly mono- or polyhydroxylated.

[0574] Fatty (poly)ethoxylated alcohols are more particularly chosen from among alcohols having 8 to 30 carbon atoms, and preferably 12 to 22 carbon atoms.

[0575] Fatty (poly)ethoxylated alcohols more particularly have one or more hydrocarbon groups, linear or branched, saturated or unsaturated, comprising 8 to 30 carbon atoms, optionally substituted, in particular by one or more hydroxyl groups (in particular 1 to 4). If they are unsaturated, these compounds may comprise one to three carbon-carbon double bonds, conjugated or not.

[0576] The (poly)ethoxylated fatty alcohol(s) preferably have the following formula: Ra-[O-CH2-CH2]n-OH with: - Ra representing a linear or branched alkyl group in C1-C40, or a linear or branched alkenyl group in C2-C30, and preferably is an alkyl group in C8-C30; - n represents an integer between 1 and 200 inclusively, preferably between 2 and 100, more particularly between 10 and 50 inclusively, and even more particularly between 15 and 30 inclusively, such as 100 or 20.

[0577] We can mention in particular lauric alcohol 20 OE, lauric alcohol 30 OE, decyl alcohol 3 OE, decyl alcohol 5 OE and oleic alcohol 20 OE.

[0578] According to a particular embodiment of the invention, the non-ionic surfactant(s) of the invention are selected from fatty acid and polyglycerol esters comprising 2 to 20 glycerol units, such as polyglycerol esters comprising 2 to 20 glycerol units and carboxylic acid(s) or polymer(s) of acid(s) carboxylic(s), saturated or unsaturated, comprising 6 to 40 carbon atoms, preferably 8 to 30 carbon atoms, or polyglycerol esters comprising 2 to 20 glycerol motifs and derivatives of vegetable oils, as well as mixtures thereof.

[0579] Preferably, the polyglycerol esters are selected from nonionic polyglycerol esters comprising 2 to 20 glycerol units and saturated or unsaturated carboxylic acid(s) comprising 6 to 40 carbon atoms, preferably 8 to 30 carbon atoms, or derived from vegetable oils, and mixtures thereof. The carboxylic acids may further comprise 1 to 3 carboxylic groups, and preferably are monocarboxylic acids. The polyglycerol compounds are more particularly mono-, di-, or tri-esters.

[0580] A titre d’exemples d’esters polyglycérolés, on peut citer les composés suivants, désignés par leur nom INCI : Polyglycéryl-2 Stéarate, Polyglyceryl-2 Isostearate, Polyglyceryl-2 Diisostéarate, Polyglyceryl-3 Diisostearate, Polyglyceryl-2-Dipolyhydroxystearate, Polyglyceryl-3 Dicitrate / Stearate, Polyglycéryl-4 Diisostearate, Polyglyceryl-4 Caprate, Polyglyceryl-4 Laurate, Polyglyceryl-5 Laurate, Poylglyceryl-5 oleate, Polyglyceryl-6 Caprylate, Polyglyceryl-6 dicaprate, Polyglyceryl-6 Distearate, Polyglyceryl-6 Caprylate / Caprate, Polyglyceryl-6 Dioleate, Polyglyceryl-6 trilaurate, Polyglycéryl-6-Polyricinoleate , Polyglyceryl-10-Dioleate, Polyglyceryl-10 Laurate, Polyglyceryl-10 Dioleate, les esters d’huile d’amande d’abricot (apricot kernel oil) polyglycérolés comprenant 3 à 10 motifs glycérol, ainsi que leurs mélanges.

[0581] In a particular embodiment, the fatty acid and polyglycerol ester(s) comprising 2 to 20 glycerol motifs are chosen from compounds with a molar mass greater than 200 g / mol, or even greater than 350 g / mol.

[0582] Non-ionic surfactants may be selected in particular from among alkyl- and polyalkyl- esters of poly(ethylene oxide), oxyalkylated alcohols, alkyl- and polyalkyl-ethers of poly(ethylene oxide), alkyl- and polyalkyl-esters of sorbitan, polyoxyethylenated or not, alkyl- and polyalkyl-ethers of sorbitan, polyoxyethylenated or not, in particular alkyl- and polyalkyl-esters of sucrose, alkyl- and polyalkyl-esters of glycerol, polyoxyethylenated or not, alkyl- and polyalkyl-ethers of glycerol, polyoxyethylenated or not, geminated surfactants, cetyl alcohol, stearyl alcohol, and mixtures thereof.

[0583] Examples of amphoteric surfactants suitable for the invention are in particular chosen from among the betaines, preferably chosen from among the alkyl betaines, in particular lauryl betaine; the N-alkylamido betaines and their derivatives, in particular cocamidopropyl betaine, lauramidopropyl betaine and N-carboxyethoxyethyl N-cocoylamidoethyl aminoacetate N-disodium; the sultaines, in particular cocoyl amidopropylhydroxy sultaine; and mixtures thereof.

[0584] Examples of anionic surfactants include alkylcarboxylic acids, alkylcarboxylates, alkyl sulfates, alkyl ether sulfates, alkyl sulfonate or sulfonic esters, alkylamidoethersulfates, alkylarylpolyethersulfates, monoglyceride sulfates, alkylsulfonates, alkylamide sulfonates, alpha-olefin sulfonates, paraffin sulfonates, alkylsulfosuccinates, alkylethersulfosuccinates, alkylamide sulfosuccinates, alkylsulfoacetates, acylsarcosinates, acylglutamates, alkylsulfosuccinamates, acylisethionates and N-acyltaurates, salts of alkyl monoesters and polyglycoside polycarboxylic acids, salts of alkyl diesters and polyglycoside-polycarboxylic acids, acyllactylates, salts of D-galactoside-uronic acids, salts of alkyl ether-carboxylic acids, salts of alkylaryl ether-carboxylic acids, salts of alkyl amidoether-carboxylic acids,and the corresponding non-salted forms of all these compounds, the alkyl and acyl groups of all these compounds having from 8 to 30 carbon atoms, preferably from 10 to 22 carbon atoms, and the aryl group designating a phenyl group. It is understood that the alkyl groups of surfactants may be linear or branched, interrupted by one or more heteroatoms or groups selected from O, S, N, C(O) or their combinations such as the ester group. Examples include sodium docusate, alkyl ethers sulfates, such as lauryl ethers sulfates, particularly of alkali or alkaline earth metals, including sodium lauryl ethers sulfate and sodium lauryl sulfate.

[0585] Non-ionic surfactants may be selected in particular from alkyl- and polyalkyl- esters of poly(ethylene oxide), oxyalkylated alcohols, alkyl- and polyalkyl-ethers of poly(ethylene oxide), alkyl- and polyalkyl-esters of sorbitan, polyoxyethylenated or not, alkyl- and polyalkyl-ethers of sorbitan, polyoxyethylenated or not, in particular alkyl- and polyalkyl-esters of sucrose, alkyl- and polyalkyl-esters of glycerol, polyoxyethylenated or not, alkyl- and polyalkyl-ethers of glycerol, polyoxyethylenated or not, geminated surfactants, cetyl alcohol, stearyl alcohol, and mixtures thereof.

[0586] Anionic surfactants can be selected from alkyl ether sulfates, carboxylates, amino acid derivatives, sulfonates, isethionates, taurates, sulfosuccinates, alkylsulfoacetates, phosphates and alkylphosphates, polypeptides, metallic salts of fatty acids in C10-C30, especially in C16-C25, in particular metallic stearates and behenates and mixtures thereof.

[0587] Cationic surfactants can be selected from alkylimidazolidiniums, such as isostearyl ethylimidonium ethosulfate, ammonium salts, such as (alkyl Ci23o)-tri(alkyl Cm)ammonium halides, in particular N,N,N-trimethyl-l-docosanaminium chloride (or Behentrimonium chloride).

[0588] Silicone surfactants can be chosen from dimethicone copolyols or silicone elastomers.

[0589] A composition according to the invention may comprise from 0.01% to 2.0% by weight of surfactant(s), preferably from 0.05% to 1.5% by weight, more preferably from 0.1% to 1.0% by weight, relative to the total weight of the composition. 5) Thickener

[0590] According to a particular embodiment, a composition according to the invention comprises 5) at least one thickener, also sometimes called a gelling agent or viscosity modifying agent.

[0591] Thickeners may be synthetic, natural or of natural origin, preferably natural or of natural origin.

[0592] Such thickeners may in particular be chosen from natural or naturally derived polymers, in particular of vegetable origin.

[0593] These gelling agents are preferably hydrophilic, that is to say soluble or dispersible in water.

[0594] Preferably, the thickening agent(s) are selected from polysaccharides, modified or native, in particular modified or unmodified starches, fructans, gellans, glucans, amylose, amylopectin, glycogen, pullulan, dextran, celluloses and their derivatives, in particular methylcelluloses, hydroxyalkylcelluloses, ethylhydroxyethylcelluloses, and carboxymethylcelluloses, mannans, xylans, lignins, arabans, galactans, galacturonans, alginate-based compounds, chitin, chitosan, glucuronoxylans, arabinoxylans, xyloglucans, glucomannans, pectic acids and pectins, arabinogalactans, carrageenans, agars, glycosaminoglucans, arabic gums, sclerotium gum, tragacanth gums, ghatti gums, karaya gums, carob gums, konjac gum, galactomannans, such as guar gums and their non-ionic derivatives,in particular hydroxypropyl guar, and ionic, biopolysaccharide gums of microbial origin, in particular scleroglucan or xanthan gums, mucopolysaccharides, carboxyvinyl polymers, polyacrylamides, 2-acrylamido-2-methylpropanesulfonic acid polymers and copolymers, possibly cross-linked and / or neutralized, water-soluble or water-dispersible silicone derivatives, such as acrylic silicones, polyether silicones and cationic silicones, and mixtures thereof.

[0595] The thickener(s) may be present in a composition according to the invention in a content ranging from 0.05% to 5.0% by weight, in particular from 0.3% to 4.0% by weight, more particularly from 0.4% to 2.5% by weight, relative to the total weight of the composition. 6) Dispersive polymers

[0596] According to a particular embodiment, a composition according to the invention comprises 6) at least one dispersing polymer.

[0597] The term “dispersing polymer” means any polymer that enables the homogeneous dispersion of composite materials in the medium and / or the homogeneous deposition of said composite materials on the application substrate of the composition, preferably cosmetic, particularly at room temperature. In other words, a dispersing polymer notably improves the diffusion on a surface or in a liquid, or the separation of composite materials, sometimes to prevent the agglomeration or sedimentation of composite materials in a fluid.

[0598] According to a particular embodiment, the dispersing polymers are selected from polyhydroxystearic acid, such as that marketed under the name Dispersun DSP OL-300 by Innospec Active Chemicals, polyglyceryl-6-polyricinoleate, such as that marketed under the name SY Glyster CRS-75 MB by Sakamoto Yakuhin, sodium stearoyl glutamate, such as that marketed under the name AMISOFT HS 11 PF by Ajinomoto, sorbitan oleate, such as that marketed in a lipophilic solvent under the name SPAN 80 by Croda, lauryl glucoside, such as that marketed in aqueous solution under the name Plantacare 1200 UP by BASF, and PEG-150 distearate, such as that marketed in water under the name Dapracare P6000 DS NV by Italmatch Chemicals.

[0599] According to a particular embodiment, the dispersing polymers are chosen from sodium dextran sulfate, such as that marketed in water under the name Dextralip 10C, by PK Chemicals), oleic acid in an oil, and / or lauric acid in an oil.

[0600] According to a particular embodiment, the dispersing polymers are selected from polyglyceryl-6-polyricinoleate, such as that marketed in oil under the name SY Glyster CRS-75 MB by Sakamoto Yakuhin; PEG-150 distearate, such as that marketed in propanediol under the name Dapracare P6000 DS NV by Italmatch Chemicals; PEG-100 stearate, such as that marketed in propanediol under the name SP MYRJ S100 by Croda; PEG-100 stearate, such as that marketed in propylene carbonate under the name SP MYRJ S100 by Croda; lauryl glucoside, such as that marketed in aqueous solution under the name Plantacare 1200 UP by BASF; and PEG-150 distearate, such as that marketed in water under the name Dapracare P6000 DS NV, by Italmatch Chemicals.

[0601] According to a particular embodiment, the dispersing polymers are chosen from sodium polymethacrylate, such as that commercially available in water under the name Darvan 7, by Vanderbilt, myristoylpullulan, such as that marketed in oil by Katakura Chikkarin, and polyglyceryl-6-polyricinoleate, such as that marketed in oil under the name SY Glyster CRS-75 MB, by Sakamoto Yakuhin.

[0602] According to a particular embodiment, the dispersing polymers are chosen from sodium lauryl ether sulfates, such as that marketed in water under the name Rhodapex ESB 30HA1 MB, by Syensqo.

[0603] According to a preferred embodiment, the dispersing polymers are selected from polyhydroxystearic acid, such as that marketed under the name Dispersun DSP OL-300 by Innospec Active Chemicals, sodium dextran sulfate, such as that marketed in water under the name Dextralip 10C by PK Chemicals), sodium polymethacrylate, such as that marketed in water under the name Darvan 7 by Vanderbilt, and myristoylpullulan, such as that marketed in oil by Katakura Chikkarin.

[0604] The dispersing polymer(s) may be present in a composition according to the invention in a content ranging from 0.05% to 10.0% by weight, in particular from 0.3% to 8.0% by weight, more particularly from 0.4% to 5% by weight, relative to the total weight of the composition.

[0605] According to a particular embodiment, the composition according to the invention comprises at least one composite material P as defined above and at least one compound selected from z1) the polymeric compounds defined below, z2) the surfactants, preferably non-ionic and anionic, defined below, and their mixtures.

[0606] The polymeric compound(s) zl) are the polymeric compounds selected from: - lignosulfonic acid, lignosulfonates, polystyrene sulfonates, polystyrene sulfonates, anionic derivatives of polyanethol, in particular polyanethol sulfonates, and mixtures thereof, - alkyl esters or ethers of polyols, particularly glycerol, - anionic polysaccharides, preferably selected from sulfated polysaccharides, in particular ulvans, dextran sulfates, carrageenans, and mixtures thereof, and carboxylate polysaccharides, in particular alginates, - cationic polysaccharides, preferably selected from polysaccharides with amine groups, in particular chitosans, - modified polysaccharides, in particular selected from polysaccharide esters, and preferably from pullulan esters, - poly(alkylene (C2-C5)imines), and preferably among polyethyleneimines and polypropyleneimines, in particular poly(ethyleneimine), - polyamino acids, and preferably proteins, - anionic acyclic polymers, bearing carboxylic groups or carboxylates of alkali or alkaline earth metals such as sodium, and selected by homo or copolymers of (meth)acrylic acid, preferably among sodium polymethacrylates and copolymers of (meth)acrylic acid with alkyl (poly)ether (meth)acrylates, in particular POE / POP (meth)acrylic acid and (meth)acrylate copolymers, and - their mixtures.

[0607] Preferably, the polymeric compound(s) zl) are selected from lignosulfonates, polystyrene sulfonates, polyanethol sulfonates, alkyl esters or glycerol ethers, dextran sulfates, lambda carrageenan, naked carrageenan, alginates, chitosans, pullulan esters, polyethyleneimines, proteins, sodium polymethacrylates, (meth)acrylic acid and (meth)acrylate copolymers of POE / POP, and mixtures thereof.

[0608] The surfactant(s) z2) are the surfactants selected from: z2-l) non-ionic surfactants selected from those comprising one or more ester groups, one or more hydroxy groups, and comprising from 10 to 50 carbon atoms, more particularly between 20 and 42 carbon atoms and more than 3 hydroxy groups, such as polyglyceryl-10 laurate, polysorbate 20; z2-2) anionic surfactants selected from saturated or unsaturated fatty acids, the hydrocarbon chain being linear or branched, preferably comprising from 6 to 24 carbon atoms, particularly from 10 to 20 carbon atoms, more particularly from 12 to 18 carbon atoms such as stearic, oleic and lauric acids, preferably of natural origin, particularly vegetable such as stearic, oleic and lauric acids; more preferably oleic and lauric acids being in the form of alkali metal salts, ammonium, amino alcohols, and alkaline earth metals, or a mixture of these compounds; z2-3) Anionic surfactants selected from alkyl sulfates, alkyl ether sulfates, the alkyl groups of surfactants may be linear or branched, interrupted by one or more heteroatoms or groups selected from O, S, N, C(O) or their association such as esters such as docusates, in particular of alkali or alkaline earth metals including sodium docusate, these surfactants may be in particular oxyethylenated and then preferably comprise from 1 to 50 ethylene oxide motifs, more particularly alkyl ether sulfates such as lauryl ether sulfates, in particular of alkali or alkaline earth metals including sodium lauryl ether sulfate.

[0609] Preferably the mass ratio R composite material(s) P / polymer(s) zl) is greater than or equal to 1, preferably between 1 / 1 and 1 / 0.001, preferably between 1 / 1 and 1 / 0.005, more preferably between 1 / 1 and 1 / 0.01.

[0610] Preferably the mass ratio R composite material(s) P / surfactant(s) z2) is greater than or equal to 1, preferably between 1 / 1 and 1 / 0.001, more preferably between 1 / 1 and 1 / 0.005, even more preferably between 1 / 1 and 1 / 0.01, more particularly is between 1 and 200, better between 1.01 and 200, even more particularly between 1 and 100; even better between 1.1 and 100.

[0611] Preferably, the mass ratio R composite material(s) P / [polymer(s) z1) + surfactant(s) z2)] is greater than or equal to 1, preferably between 1 / 1 and 1 / 0.005, more preferably between 1 / 1 and 1 / 0.01. Adjuvants

[0612] A composition according to the invention may further comprise at least one adjuvant commonly used in the cosmetic field other than 1) to 6) chosen from perfumes, film-forming polymers, pH adjusters (acids or bases), for example citric acid, tartaric acid or oxalic acid, chelating agents, preservatives, softeners, sweeteners, antifoaming agents, fillers, trace elements, propellants, and mixtures thereof.

[0613] Of course, a person skilled in the art will take care to choose this or these possible additional compounds and / or their quantity in such a way that the advantageous properties of a composition according to the invention are not, or substantially not, altered by the envisaged addition.

[0614] As stated previously, a composition according to the invention can be cosmetic, and preferably is cosmetic.

[0615] A composition according to the invention is non-therapeutic.

[0616] A composition according to the invention is generally suitable for topical application to the skin and therefore generally comprises a physiologically acceptable medium, i.e. compatible with the skin.

[0617] Preferably, this is a cosmetically acceptable medium, that is to say, one which has a pleasant colour, odor and feel and does not generate unacceptable discomforts, that is to say, tingling, pulling, which may deter the user from applying this composition. Galenic forms of the compositions

[0618] Compositions, particularly cosmetics, containing the composite materials according to the invention can be prepared according to techniques well known to those skilled in the art.

[0619] They can be presented in all classic galenic forms according to the applications envisaged and are adapted to a topical application, that is to say to an application on the surface of the keratinous materials considered.

[0620] Cosmetic compositions may be in the form of an aqueous or hydroalcoholic gel.

[0621] They can be in the form of an emulsion, simple or complex (O / W, W / H, O / W / H or W / O / W), such as a cream, a milk, or a cream gel.

[0622] They can also be in anhydrous form, for example in the form of an oil.

[0623] The term "anhydrous composition" means a composition containing less than 5% by weight of water, or even less than 2% of water, better less than 1% of water, and is in particular free of water, the water possibly present not being added during the preparation of the composition but corresponding to the residual water supplied by the mixed ingredients.

[0624] Cosmetic compositions can, for example, be used as a makeup product.

[0625] Cosmetic compositions may, for example, be used as skincare and / or sun protection products for the face and / or body. They may have a liquid to semi-liquid consistency and the appearance of a white or colored cream, with varying degrees of smoothness, an ointment, a milk, a gel-cream, a lotion, a serum, a paste, or a mousse. They may also be applied to the skin in aerosol form. They may also be in solid form, for example, as a stick.

[0626] Cosmetic compositions may be in the form of skin care or semi-mucous membrane care products, such as a protective composition, cosmetic care composition for the face, for the lips, for the hands, for the feet, for anatomical folds or for the body (for example day creams, night cream, day serum, night serum, makeup remover cream, makeup base, protective or care body lotion, after-sun lotion, lotion, gel or mousse for skin or scalp care, serum, mask or after-shave composition).

[0627] The composition can be applied by hand or using an applicator. Processes and uses

[0628] The present invention also relates to the use, preferably cosmetic, non-therapeutic, of composite materials P according to the invention to filter UV radiation, preferably UV-B, comprising at least the application on any surface, preferably on keratinous materials, of a composition, preferably cosmetic, comprising at least one composite material P as defined above.

[0629] The present invention thus relates to a method, preferably cosmetic, non-therapeutic, for filtering UV radiation, in particular UV-B, comprising at least the application to a surface, preferably keratinous materials, of a composition, preferably cosmetic, comprising at least one composite material P as defined above.

[0630] Preferably, the present invention relates to a non-therapeutic cosmetic process for filtering UV radiation, in particular UV-B, comprising at least the application to keratinous materials of a composition comprising at least one composite material P as defined above.

[0631] According to yet another aspect of it, the present invention also relates to the non-therapeutic cosmetic use of a cosmetic composition comprising at least one composite material P defined previously, to prevent the appearance on the skin, in particular on the face, décolletage, arms, hands and / or shoulders, of darker and / or more coloured spots giving the skin a heterogeneity of colour.

[0632] The present invention also relates to a non-therapeutic cosmetic process for limiting skin darkening and / or improving the color and / or homogeneity of the complexion comprising the application on the surface of the keratinous material of at least one cosmetic composition comprising at least one composite material P as defined above.

[0633] The present invention further relates to the non-therapeutic cosmetic use of a cosmetic composition comprising at least one composite material P as defined above, to prevent premature aging of the skin, in particular of the skin of the face, décolleté, arms, hands and / or shoulders.

[0634] According to one of its aspects, the present invention relates to composite materials P as defined above, for their use as agents for filtering UV radiation, in particular UV-B.

[0635] For the purposes of the present invention, "prevent" or "prevention" means reducing, at least in part, the risk of the occurrence of a given phenomenon, for example the signs of aging of a keratinous material or the appearance on the skin of darker and / or more colored spots giving the skin heterogeneity of color and / or premature aging of the skin.

[0636] In the description and examples, percentages are weight or molar percentages. The ingredients are mixed in the order and under the conditions easily determined by a person skilled in the art.

[0637] The invention will now be described by means of the following examples, given of course by way of illustration and not limitation of the invention. Examples

[0638] Example 1: Synthesis of bismuth oxychloride particles according to the invention

[0639] Bismuth oxychloride particles 1 are synthesized according to the preparation method described below.

[0640] A solution of bismuth nitrate pentahydrate Bi(NO3)3-5H2O (0.40 M) and D-mannitol (2 M) is prepared in 800 mL of water and stirred until the reagents are completely dissolved. 160 mL of a potassium chloride solution (1 equivalent with respect to bismuth) is then added. A white solid precipitates. After 30 minutes, this mixture is transferred to a Teflon autoclave-type reactor and heated for 12 hours at 160 °C. The bismuth oxychloride particles are isolated by centrifugation and washed 3 times with water before being oven-dried at 60 °C.

[0641] The morphology of bismuth oxychloride particles was determined by direct observation using transmission electron microscopy. 1 to 5 milligrams of dry particles are dispersed in 10 mL of absolute ethanol and treated in an ultrasonic bath for two minutes. 5 µL of the dispersion are then placed on an observation grid (copper with a carbon surface layer) and dried at 40 °C.

[0642] The observation is carried out with a Hitachi HT 7700 transmission electron microscope at an accelerating voltage of 100 kV. The average dimensions are obtained via particle size measurement by image analysis using ImageJ software (CA Schneider, WS Rasband, KW Eliceiri, NIH Image to ImageJ: 25 years of image analysis, Nat. Methods. 9 (2012) 671-675).

[0643] The bismuth oxychloride particles 1 are platelets of the following average dimensions: Average length L: 59 + / -18 nm Average width 1: 38 + / -10 nm Average thickness e: 16 + / -5 nm.

[0644] Example 2: Syntheses of composite materials according to the invention

[0645] Example 2.A: Synthesis of composite material A bismuth oxychloride - aluminium hydroxide - sodium stearate

[0646] The bismuth oxychloride particles obtained according to Example 1 are stirred in water at a concentration of 100 g / L at room temperature. The temperature of the medium is then raised to 70 °C for 30 minutes. The pH is adjusted to 8 with sodium hydroxide. A 0.5 M sodium aluminate solution in water is added dropwise in an amount such that the sodium aluminate / bismuth oxychloride molar ratio is 0.0325. After the addition is complete, the reaction medium is stirred for 1 hour at 70 °C. The pH is adjusted to 8 with the addition of sulfuric acid. An aqueous solution of sodium stearate at 30 g / L, heated to 80 °C, is added dropwise to the reaction mixture in an amount such that the sodium stearate / bismuth oxychloride molar ratio is 0.15. The mixture is stirred for 1 hour at 70 °C. The pH is adjusted to 6.5 with acid. sulfuric. After cooling, composite material A is isolated by centrifugation, washed three times with water and then dried in an oven at 50 °C.

[0647] The composite material A is obtained in the form of a beige powder and is characterized by UV / Vis spectrophotometry.

[0648] Example 2.B: Synthesis of composite material B bismuth oxychloride sodium stearate

[0649] The bismuth oxychloride particles 1 obtained according to Example 1 are stirred in water at a concentration of 100 g / L at room temperature. The temperature of the medium is then raised to 70 °C for 30 minutes. The pH is adjusted to 8 with sodium hydroxide. An aqueous solution of sodium stearate at 30 g / L, heated to 80 °C, is added dropwise to the reaction medium in an amount such that the sodium stearate / bismuth oxychloride molar ratio is 0.15. The mixture is stirred for 1 hour at 70 °C. The pH is adjusted to 6.5 with sulfuric acid. After cooling, the composite material B is isolated by centrifugation, washed three times with water, and then dried in an oven at 50 °C.

[0650] The composite material B is obtained in the form of a beige powder and is characterized by UV / Vis spectrophotometry.

[0651] Example 2.C: Synthesis of the composite material C bismuth oxychloride - aluminium hydroxide - oleic acid

[0652] Bismuth oxychloride particles 1 obtained according to Example 1 are stirred in water at a concentration of 100 g / L at room temperature. The temperature of the medium is then raised to 70 °C for 30 minutes. The pH is adjusted to 8 with sodium hydroxide. A 0.5 M sodium aluminate solution in water is added dropwise in an amount such that the sodium aluminate / bismuth oxychloride molar ratio is 0.0325. After the addition is complete, the reaction medium is stirred for 1 hour at 70 °C. The pH is adjusted to 8 by adding sulfuric acid. In parallel, an aqueous solution of 30 g / L oleic acid is heated to 80 °C and the pH is adjusted to 10 with sodium hydroxide. This solution is added dropwise to the reaction mixture in such a quantity that the molar ratio of oleic acid / bismuth oxychloride is equal to 0.15. The mixture is stirred for 1 hour at 70 °C.The pH is adjusted to 6.5 with sulfuric acid. After cooling, composite material C is isolated by centrifugation, washed three times with water, and then dried in an oven at 50 °C.

[0653] The composite material C is obtained in the form of a sticky grey paste and is characterized by UV / Vis spectrophotometry.

[0654] Example 2.D: Synthesis of the composite material D bismuth oxychloride - silica - sodium stearate

[0655] The bismuth oxychloride particles 1 obtained according to Example 1 (2 g) are stirred in 40 mL of distilled water. While stirring, the temperature of the mixture is raised to 80 °C. At this temperature, 3.24 mL of an aqueous sodium silicate solution prepared from a 26.9 wt. solution and diluted by a factor of 10 are added dropwise. Stirring and heating are maintained for 5 hours, and then the reaction mixture is allowed to cool to room temperature. The product Dl, bismuth oxychloride and silica, is isolated by centrifugation and washed twice with water before being oven-dried at 60 °C under vacuum (less than 100 mbar).

[0656] The product Dl is isolated in the form of a white powder and is characterized by UV / Vis spectrophotometry and Fourier transform infrared spectroscopy.

[0657] Product Dl is then stirred in water at a concentration of 100 g / L at room temperature. The temperature of the medium is then raised to 70 °C for 30 minutes. An aqueous solution of sodium stearate at 30 g / L, heated to 80 °C, is added dropwise to the reaction medium in an amount such that the molar ratio of sodium stearate to bismuth-silica oxychloride is 0.15. The reaction medium is stirred for 1 hour at 70 °C. The pH is adjusted to 6.5 with sulfuric acid. After cooling, the composite material D is isolated by centrifugation, washed twice with water, and then dried in an oven at 50 °C.

[0658] The composite material D is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0659] Table 1 below details the compositions of products A to D obtained. For the sake of simplicity, any hydration of the compounds is not specified.

[0660] [Tables 1] Product Composition of composite materials A BiOCI - Al(OH)₂ - sodium stearate B. BiOCI - SiO₂,- - sodium stearate C BiOCI - Al(OH)₃ - oleic acid D BiOCI - SiO₂ - sodium stearate

[0661] Example 2.E: Synthesis of composite materials E bismuth oxychloride-carrageenan, with a mass ratio of 1.66

[0662] A solution of carrageenan (INCI name CARRAGEENAN) (0.6 g) in 100 mL of water is heated to 80 °C and stirred until the polymer is completely dissolved. The mixture is then cooled to room temperature.

[0663] To this solution is added 1 g of bismuth oxychloride particles 1 obtained according to Example 1, and the suspension is ultrasonically stabilized for 15 minutes, then shaken overnight. The resulting white dispersion is then centrifuged. The pellet is washed with ethanol and is centrifuged again. The resulting solid is dried in a vacuum oven at 50 °C.

[0664] The composite material E is isolated in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0665] Example 2.F: Synthesis of F bismuth oxychloride-chitosan composite materials, with a mass ratio of 0.60

[0666] A solution of chitosan (Kiosmetine-CSG marketed by Kitozyme) (1.64 g) in 100 mL of water is adjusted to pH equal to 4 with lactic acid, then stirred until complete dissolution of the polymer.

[0667] To this solution is added 1 g of bismuth oxychloride particles 1 obtained according to Example 1, and the suspension is ultrasonically aerated for 15 min, then stirred overnight. The light beige dispersion is then atomized at 160 °C, with a pump flow rate of 15%, a suction flow rate of 80% and a node count of 5 (Device type: BUCHI B-290 Mini-Atomizer).

[0668] The composite material F is isolated as a beige powder and is characterized by UV / Vis spectrophotometry.

[0669] Example 2.G: Synthesis of G bismuth oxychloride-sodium alginate composite materials, with a mass ratio of 1.06

[0670] A solution of sodium alginate (0.94 g) in 100 mL of water is heated to 40 °C and stirred until the polymer is completely dissolved. The mixture is then cooled to room temperature.

[0671] To this solution is added 1 g of bismuth oxychloride particles 1 obtained according to Example 1, and the suspension is ultrasonically aerated for 15 minutes, then agitated overnight. The resulting white dispersion is then atomized at 160 °C, with a pump flow rate of 15%, a suction flow rate of 80% and a node count of 2 (Device type: BUCHI B-290 Mini-Atomizer).

[0672] The composite material G is isolated in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0673] Example 2.H: Synthesis of H-bismuth oxychloride-sodium alginate composite materials, with a mass ratio of 1.06

[0674] A solution of sodium alginate (0.94 g) in 100 mL of water is heated to 80 °C and stirred until the polymer is completely dissolved. The mixture is then cooled to room temperature.

[0675] To this solution is added 1 g of bismuth oxychloride particles 1 obtained according to Example 1, and the suspension is ultrasonically stabilized for 15 min, then shaken overnight. The resulting white dispersion is then lyophilized.

[0676] The composite material H is isolated as a cottony white solid and is characterized by UV / Vis spectrophotometry.

[0677] Example 2.1: Synthesis of composite materials I bismuth oxychloride - sodium dextran sulfate, with a mass ratio of 0.90

[0678] A solution of sodium dextran sulfate (Dextralip 10C, marketed by Safic-Alcan) (1.1 g) in 100 mL of water is stirred until the polymer is completely dissolved.

[0679] To this solution is added 1 g of bismuth oxychloride particles 1 obtained according to Example 1. The suspension is ultrasonically aerated for 15 minutes, then agitated overnight. The white dispersion is then atomized at 120 °C, with a pump flow rate of 15%, a suction flow rate of 80% and a node count of 4 (Device type: BUCHI Mini-Atomizer B-290).

[0680] The composite material I is isolated in the form of beige powder and is characterized by UV / Vis spectrophotometry.

[0681] Example 2.J: Synthesis of J bismuth oxychloride-myristoyl pullulane composite materials, with a mass ratio of 0.71

[0682] A solution of myristoyl pullulane (marketed by Katakura Chikkarin) (1.4 g) in 100 mL of isododecane is stirred until complete dissolution of the polymer.

[0683] To this solution, 1 g of bismuth oxychloride particles 1 obtained according to Example 1 is added, and the suspension is ultrasonically aerated for 15 minutes, then stirred overnight. The resulting white dispersion is centrifuged, washed with ethanol, and centrifuged again. The solid obtained is dried in a vacuum oven at 50 °C.

[0684] The composite material J is isolated in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0685] Table 2 below details the compositions of the products E to J obtained. For the sake of simplicity, any hydration of the compounds is not specified.

[0686] [Tables2] Product Method Composition of composite materials Mass ratio m(BiOCl) / m(polymer) E Centrifugation BiOCl - Carrageenan 1.66 F Atomization BiOCl - Chitosan 0.60 G Atomization BiOCl - Sodium alginate 1.06 H Lyophilization BiOCl - Sodium alginate 1.06 I Atomization BiOCl - Sodium dextran sulfate 0.90 J Centrifugation BiOCl - Myristoyl pullulan 0.71

[0687] Example 2.K: Synthesis of K-composite materials bismuth oxychloride -triethoxy (2,4,4-trimethylpentyl)silane

[0688] Bismuth oxychloride particles according to Example 1 (1 g) are dispersed in 20 mL of distilled water and ultrasonically dispersed for 2 minutes. The medium is then stirred at 50 °C.

[0689] A solution of triethoxy(2,4,4-trimethylpentyl)silane (379 mg) in ethanol (21 mL) is added dropwise.

[0690] The pH is adjusted to 2 with the addition of sulfuric acid H2SO4 5 N.

[0691] The mixture is stirred for 3 hours at 50 °C.

[0692] After cooling to room temperature, the composite material K is isolated by centrifugation, washed three times with water and then once with ethanol and then dried in an oven at 50 °C under vacuum (less than 100 mbar).

[0693] The composite material K is obtained in the form of a light grey powder and is characterized by UV / Vis spectrophotometry.

[0694] Example 2.L: Synthesis of L-bismuth oxychloride-benzyltriethoxysilane composite materials

[0695] Bismuth oxychloride particles according to Example 1 (1 g) are dispersed in 20 mL of distilled water and ultrasonically agitated for 2 minutes. The medium is then stirred at 50 °C.

[0696] A solution of benzyltriethoxysilane (349 mg) in ethanol (19 mL) is added dropwise.

[0697] The pH is adjusted to 2 with the addition of sulfuric acid H2SO4 5 N.

[0698] The mixture is stirred for 3 hours at 50 °C.

[0699] After cooling to room temperature, the composite material L is isolated by centrifugation, washed three times with water and then once with ethanol and then dried in an oven at 50 °C under vacuum (less than 100 mbar).

[0700] The composite material L is obtained in the form of a light grey powder and is characterized by UV / Vis spectrophotometry.

[0701] Example 2.M: Synthesis of composite materials M bismuth oxychloride - 2 - [methoxy (polyethyleneoxy)propyl]trimethoxysilane (n = 1)

[0702] Bismuth oxychloride particles according to Example 1 (1 g) are dispersed in 20 mL of distilled water and ultrasonically agitated for 2 minutes. The medium is then stirred at 50 °C.

[0703] A solution of 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane (n = 1) (327 mg) in ethanol (19 mL) is added dropwise.

[0704] The pH is adjusted to 2 with the addition of dilute sulfuric acid H2SO4 (0.2 M).

[0705] The mixture is stirred for 3 hours at 50 °C.

[0706] After cooling to room temperature, the composite material E is isolated by centrifugation, washed three times with water and then once with ethanol and then dried in an oven at 80 °C under vacuum (less than 100 mbar).

[0707] The composite material M is obtained in the form of a light grey powder and is characterized by UV / Vis spectrophotometry.

[0708] Example 2.N: Synthesis of composite materials N bismuth oxychloride -[hydroxy(polyethyleneoxy)propyl]triethoxysilane (n = 8 -12)

[0709] Bismuth oxychloride particles 1 according to Example 1 (1 g) are dispersed in 20 mL of distilled water and ultrasonically dispersed for 2 minutes. The medium is then stirred at 50 °C.

[0710] A 50 wt% [hydroxy(polyethyleneoxy)propyl]triethoxysilane (n = 8 - 12) solution in ethanol (1.8 mL), diluted with 18 mL of ethanol, is added dropwise.

[0711] The pH is adjusted to 2 with the addition of dilute sulfuric acid H2SO4 (0.2 M).

[0712] The mixture is stirred for 3 hours at 50 °C.

[0713] After cooling to room temperature, the composite material F is isolated by centrifugation, washed three times with water and then once with ethanol and then dried in an oven at 80 °C under vacuum (less than 100 mbar).

[0714] The composite material N is obtained in the form of a light grey powder and is characterized by UV / Vis spectrophotometry.

[0715] Table 3 below details the compositions of the products K to N obtained. For the sake of simplicity, any hydration of the compounds is not shown.

[0716] [Tables3] Product Composition of composite materials K BiOCl - triethoxy(2,4,4--trimethoxy(2,4,4-trimethoxy(1- ...

[0717] Example 3: Absorbance spectra of bismuth oxychloride composite materials according to the invention

[0718] UV-visible spectrophotometric absorbance spectra of composite materials according to the invention and prepared according to example 2 were obtained.

[0719] They were obtained by UV-visible spectrophotometry on 0.005 wt% dispersions of composite in isododecane for composite materials A, B, C, D, J, K and L or in water for composite materials E, F, G, H, I, M and N.

[0720] The quartz cell used for absorbance measurements is 1 cm on each side. The spectrophotometer used is the Genesys 10S from Thermo Fisher Scientific.

[0721] Measurement of absorbance of composite materials A, B, C, D, J, K, L in isododecane:

[0722] The lipophilic dispersion of bismuth oxychloride composite materials and surface chemical compounds, at 0.05 wt%, is exposed to ultrasound for 1 minute and then stirred with a magnetic stirrer for 10 minutes. It is then The sample is then ultrasonically heated for 1 minute, diluted to 0.005% by mass, ultrasonically heated again, and stirred magnetically for 5 hours. The sample is then ultrasonically heated for 1 minute immediately before the absorbance measurement is taken.

[0723] Measurement of absorbance of composite materials E, F, G, H, I, M and N in water:

[0724] The aqueous dispersion of bismuth oxychloride composite materials and surface chemical compounds, at 0.01 wt%, is exposed to ultrasound for 15 minutes and then stirred with a magnetic stirrer for 15 hours. It is then diluted to 0.005% and stirred again under magnetic stirring for 20 min before performing the absorbance measurement.

[0725] The spectra of the materials according to the invention (A to N) are compared to bismuth oxychloride particles 1 prepared according to Example 1, dispersed at 0.005% by mass in water or in isododecane.

[0726] Beyond a predetermined threshold value for UV absorbance measurement, UV radiation filtration is considered effective. In particular, composite materials having a UV absorbance threshold, in the dispersion medium comprising said composite materials, at a mass fraction of 0.005% greater than 0.22% are considered effective for UV radiation filtration.

[0727] Absorbance spectra are shown in figures 1 to 14.

[0728] The results are grouped in the following Table 4.

[0729] [Tables4] Absorbance Composite A Composite B Composite C Composite D Composite E Composite F Absorbance at 22 μm 0.51 0.52 0.73 0.25 0.93 L52 Absorbance at 300 nm 0.59 0.61 0.83 0.30 1Æ 8 1.47 Absorbance at 400 μm 0.26 0.24 0.27 0.21 0.47 0.31 Absorbance at 62 μm 0.09 0.08 0.07 0.14 0.20 0.06 Absorbance Composite G Composite H Composite I Composite J Composite K Composite L Absorbance at 220 nm 1.03 1.31 1.56 0.60 0.33 0.26 Absorbance at 300 nm 1.16 1.39 1.55 0.74 0.45 0.36 Absorbance at 400 nm 0.47 0.49 0.36 0.56 0.28 0.21 Absorbance at 620 nm 0.23 0.21 0.09 0.29 0.11 0.00 Absorbance Composite M Composite N Bismuth oxychloride 1 in water Bismuth oxychloride 1 in Fisododecane at 220 nm 0.30 0.26 0.15 0.14 Absorbance at 300 nm 0.29 0.29 0.18 0.18 Absorbance at 400 nm 0.24 0.24 0.16 0.11 Absorbance at 620 nm 0.15 0.18 0.12 0.05

[0730] Composite materials according to the invention show good UV absorption and consequently effective UV filtration.

[0731] Absorbance spectra also show that composite materials according to the invention have high transparency in the visible range between 400 and 780 nm.

Claims

Demands

1. A process for preparing a composite material P comprising: - one or more particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; and - at least one chemically inert compound b), selected from b)i) organic compounds with a carboxy group, b)ii) polymers, b)iii) silicon organic compounds, b)iv) inorganic compounds, and mixtures thereof, said process comprising at least the steps of: (i) having at least some particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, of general formula BiO 1+ xHal j +y 'zH 2 O in which -0.3 < x < 0.3;-0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably chlorine, together with its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, optionally in dispersion in at least one solvent or mixture of solvents (e1); (ii) have at least one chemically inert compound (b) and / or at least one precursor (c) of one or more chemically inert compounds (b), optionally in a solvent or mixture of solvents (e2); (iii) bring together the particles (a) or the dispersion (i), and the chemically inert compounds (b) and / or the at least precursor (c), optionally in a solvent or mixture of solvents described in (ii) to form the composite material P; (iv) isolate said composite material P.;

2. A process for preparing a composite material P comprising: - one or more particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm; and - at least one chemically inert compound b), selected from b)i) organic compounds with a carboxy group, b)ii) polymers, b)iii) the

3. organic compounds of silicon, b)iv) inorganic compounds, and mixtures thereof, said process, said process comprising at least the steps of: (Ali) having a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, together with its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent e), in particular in an amount from 0.05 g / L to 500 g / L; (Al-ii) have a solution of at least one chemically inert compound b) chosen from b)i) to b)iv) and their mixtures, as defined above, and / or at least one precursor c) intended to form the chemically inert compound(s) b), possibly mixed with at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (Al-iii) bring said dispersion (Ali) and said solution (Al-ii) into contact to form the composite material P; (Al-iv) isolate said composite material P. A process for preparing a composite material P comprising at least two chemically inert compounds b) selected from b)i) organic compounds with a carboxy group, b)ii) polymers, b)iii) silicon organic compounds, b)iv) inorganic compounds, and mixtures thereof, and / or their precursor(s) c), optionally mixed with at least one solvent e), comprising the steps of: (A-2-i) have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, of general formula BiO 1+ xHal / +y -zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, as well as its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent e), in particular in an amount from 0.05 g / L to 500 g / L;

4. (A-2-ii) have an aqueous solution of a chemically inert compound b) selected from b)i) organic compounds with a carboxy group, b)ii) polymers, b)iii) organic silicon compounds, b)iv) inorganic compounds, and mixtures thereof, preferably an inorganic compound b)iv), or a precursor c), in particular sodium silicate; (A-2-iii) bringing said dispersion (A-2-i) and said solution (A-2-ii) together to form particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and a chemically inert compound b) selected from b)i) organic compounds with a carboxy group, b)ii) polymers, b)iii) organic silicon compounds, b)iv) inorganic compounds, and / or one of its salts, and mixtures thereof, preferably an inorganic compound b)iv), more preferably silica; (A-2-iv) isolate said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and of a chemically inert compound b) selected from b)i) organic compounds with carboxy group, b)ii) polymers, b)iii) organic silicon compounds, b)iv) inorganic compounds, and / or one of its salts, and mixtures thereof, preferably an inorganic compound b)iv), more preferably silica; (A-2-v) dispersing said PI particles obtained in (A-2-iv) in at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-2-vi) have a solution of at least one chemically inert compound b) chosen from b)i) organic compounds with a carboxy group, b)ii) polymers, b)iii) organic silicon compounds, b)iv) inorganic compounds, and / or one of its salts, and mixtures thereof, preferably a compound b) chosen from organic compounds with a carboxy group b)i) or one of its salts, possibly mixed with at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-2-vii) bring said dispersion (A-2-v) and said solution (A-2-vi) into contact to form the composite material P; (A-2-viii) isolate said composite material P. Process for preparing a composite material P comprising an inert compound b) selected from b)iv) oxides, hydroxides and oxy- aluminium hydroxides and their hydrates, such as alumina, said process comprising the steps of: (A-4-i) to have a dispersion of bismuth oxyhalide(s) particles a), in particular bismuth oxychloride, and its solvates, such as its hydrates, of general formula BiO 1+ xHal / +y 'zH 2 O in which -0.3 < x < 0.3; -0.3 < y < 0.3 and 0 < z < 10 for their undoped version, and Hal denotes a halogen selected from chlorine, fluorine, iodine and bromine, and preferably is chlorine, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, in at least one solvent e), in particular in an amount from 0.05 g / L to 500 g / L; (A-4-ii) have a solution of aluminium salts available, in at least one solvent, in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-4-iii) bring said dispersion (A-4-i) and said solution (A-4-ii) into contact; (A-4-iii') optionally, isolate said mixture from step (A-4-iü); (A-4-iii”) optionally, subject said mixture of step (A-4-iii) or said mixture possibly isolated from step (A-4-iii') to a calcination step to obtain particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and of aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina; (A-4-iii'”) optionally, dispersing said particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and aluminium oxide, hydroxide or oxyhydroxide or their hydrates, such as alumina (A-4-iii), (A-4-iii') or (A-4-iii”), in at least one solvent e), in particular in an amount ranging from 0.05 g / L to 500 g / L; (A-4-iv) have a solution of at least one chemically inert compound b) chosen from b)i) to b)iv) as defined above, other than aluminium oxides, hydroxides or oxyhydroxides or their hydrates, such as alumina, or aluminium salts and / or one of its salts, preferably at least one chemically inert compound b) chosen from b)i), b)ii) or b)iii), optionally in mixture with at least one solvent e), in particular in an amount from 0.05 g / L to 500 g / L; (A-4-v) bring together the mixture, product or dispersion obtained at the end of step (A-4-iii), (A-4-iii'), (A-4-iii”) or (A-4-iü'”), and said solution (A-4-iv) to form the composite material P; (A-4-vi) isolate said composite material P.

5. A preparation method according to any one of claims 1 to 4, characterized in that said precursor(s) (c) intended to form the chemically inert compounds (b) are selected from: - inorganic metallic precursors of chemical elements and their hydrates, in particular solubilized metal oxides, notably sodium silicates or aluminates, halides and their hydrates, nitrates and their hydrates, carbonates and their hydrates, sulfonates and their hydrates, sulfates and their hydrates, phosphates and their hydrates, - organic metallic precursors and their hydrates, in particular alkoxides and their hydrates, carboxylates and their hydrates, lactates and their hydrates, citrates and their hydrates, - esters, in particular fatty acid esters, preferably selected from linear or branched fatty acid esters comprising 8 to 24 carbon atoms,more preferentially of 8 to 20 carbon atoms, and in particular fatty acid triglycerides, - their mixtures.,

6. Composition, preferably cosmetic, comprising at least one composite material P comprising one or more particles of bismuth oxyhalide(s) a), in particular bismuth oxychloride, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, preferably constituting the core of said composite material P, and at least one chemically inert compound b) selected from b)i) organic compounds with carboxy group(s), b)ii) polymers, b)iii) silicon organic compounds, b)iv) inorganic compounds, and mixtures thereof, preferably present on the surface of the core of said composite material P.

7. Composition according to the preceding claim, comprising: (i) a composite material P comprising one or more particles of bismuth oxyhalide(s) (a), in particular bismuth oxychloride, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, preferably constituting the core of said composite material P, and at least one chemically inert compound (b) selected from (b)i) organic compounds with carboxy group(s), (b)ii) polymers, (b)iii) silicon organic compounds, (b)iv) inorganic compounds, and mixtures thereof, preferably present on the surface of the core of said composite material P; (ii) at least one aqueous phase and / or at least one oily phase; and (iii) optionally at least one compound selected from: (1) UV filters separate from composite materials P; (2) colorants; (3) cosmetic active ingredients for the care of keratinous materials; (4) surfactants; (5) thickeners; 6) Dispersive polymers, and their mixtures.

8. Composition according to any one of claims 6 or 7, said composite materials P being present in a content from 0.5% to 50% by weight, preferably from 1% to 35% by weight, even better from 2% to 30% by weight, relative to the total weight of the composition.

9. Composite material P comprising one or more particles of bismuth oxyhalide(s) (a), in particular bismuth oxychloride, and its solvates, such as its hydrates, the largest average dimension of said particles being less than 400 nm, preferably constituting the core of said composite material P, and at least one chemically inert compound (b), preferably present on the surface of the core of said composite material P, and selected from: (b)i) organic compounds with carboxy group(s), in particular linear or branched fatty acids comprising from 8 to 24 carbon atoms, (b)ii) polymers, in particular polyethylene glycols, polyethylene amine, polypropylene glycols, polyvinyl alcohols, polyacrylic acids and their salts, polymethacrylic acids and their salts, polymethyl methacrylates, polyvinyl sulfonates, polystyrene sulfonates, polylactic acids and their salts, the polycaprolactones,polyglycolic acids, polyacetoacetates, poly(lactic-co-, glycolics), celluloses and their derivatives, alginic acids and their salts, carrageenans, starches, pectins, inulins, dextrans and their derivatives, xanthan gum, ulvans, lignosulfonates and their salts, chitins and chitosans, pullulanes, polyvinyl alcohols and polyhydroxystearic acid, and / or their copolymers, b)iii) organic silicon compounds, in particular alkoxysilanes, and especially monoalkoxysilanes, dialcoxysilanes, trialcoxysilanes, their oligomers and their polymerized forms, b)iv) inorganic compounds, in particular inorganic oxides, possibly hydrated, and their mixtures.

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