Use of a composite material of bismuth oxycarbonate and inorganic compounds for ultraviolet radiation filtration

Abstract

Use of a Bismuth Oxycarbonate Composite Material and Inorganic Compounds for Ultraviolet Radiation Filtration. The present invention relates to the use of a composite material comprising at least a) bismuth oxycarbonate particles of formula (I) (BiO)2-x(CO3), as well as its solvates, such as its hydrates, wherein -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm, and b) at least one inorganic compound selected from oxides and / or hydroxides of formula [(M(v) y)p Oz(OH)t]q (H2O)w; for filtering UV-A and / or UV-B rays, preferably UV-B, as well as composite materials, their preparation process, and compositions incorporating them. Figure for the abstract: None

Description

Title of the invention: Use of a composite material of bismuth oxycarbonate and inorganic compounds for the filtration of ultraviolet radiation Technical field

[0001] The present invention relates to the field of sun protection and more particularly to the use of composite materials of bismuth oxycarbonate, as well as its solvates, such as its hydrates, and inorganic compounds, for the filtration of ultraviolet radiation.

[0002] The invention also relates to composite materials of bismuth oxycarbonate, as well as its solvates, such as its hydrates, and inorganic compounds, and compositions, in particular cosmetic compositions, comprising such materials.

[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 tanning of the human epidermis. However, rays with wavelengths between 280 and 320 nm, called UV-B rays, are detrimental to the development of a natural tan. This exposure is also likely to induce an alteration of the biomechanical properties of the epidermis which results in the appearance of wrinkles leading to premature aging of the skin.

[0005] 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 UVA 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.).

[0006] In addition, prolonged exposure to the sun can further dry out the hair, making it brittle.

[0007] Therefore, protection of keratinous materials, especially human ones, such as skin, is essential. Prior art

[0008] 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.

[0009] Many photoprotective cosmetic compositions for the skin have been proposed to date. They generally contain organic UV filters and / or Inorganic UV filters 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 such as titanium dioxide (TiO2) or zinc oxide (ZnO).

[0010] 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.

[0011] In addition, photoprotection from inorganic UV filters is today a very important expectation of consumers, as they consider mineral sunscreens safer.

[0012] TiO2 and ZnO are the most common mineral UV filters used.

[0013] However, one of the major drawbacks of such mineral filters lies in the fact that, once applied to the skin, they produce a whitening effect on the latter which is cosmetically undesirable and generally not appreciated by users.

[0014] This effect is all the more pronounced when the concentration of mineral filters in the composition is high, which limits their concentration in sun formulations.

[0015] To avoid this problem, it would of course be possible to use reduced quantities of inorganic filter(s), but the resulting compositions, which would certainly lead to films having acceptable transparency on the skin, would then no longer offer suitable protection in the UV range, which greatly limits the interest of such an option.

[0016] Furthermore, the use of large quantities of these UV filters induces, in addition to significant whitening, unpleasant sensations after application to the skin, and in particular causes sensations of roughness and dryness on the skin in the case of significant and regular use of the products.

[0017] 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. Statement of the invention

[0018] There therefore remains a need for inorganic UV filters that are effective in photoprotection and do not present the disadvantages described above. above.

[0019] In particular, there remains a need for inorganic UV filters capable of effectively blocking UV rays, especially in the UV-B and UV-A range, and particularly UV-B rays, having high transparency to visible light, which do not bleach the keratinous materials on which they are applied and having good cosmetic properties.

[0020] 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.

[0021] The present invention aims precisely to propose new mineral UV filters making it possible to meet these expectations. Summary of the invention

[0022] Thus, according to a first aspect, the present invention relates to the use of a composite material comprising:

[0023] a) at least one bismuth oxycarbonate particle of formula (I) (BiO)2.x(CO3), as well as its solvates, such as its hydrates, wherein -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm; and

[0024] b) at least one inorganic compound selected from the oxides and / or hydroxides of formula [(M^,)p OZ(OH),]? (H2O)W, ;

[0025] in which:

[0026] - y is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably less than 10, more preferably less than 5, and even more preferably denotes 1 or 2 or 3;

[0027] - z is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably z is less than 10, more preferably less than 5;

[0028] -1 is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably t is less than 10, more preferably t is less than 5;

[0029] - M is a metal, an alkaline earth metal or a metalloid, preferably chosen among silicon Si, titanium Ti, iron Fe, zinc Zn, niobium Nb, tantalum Ta, cerium Ce, manganese Mn, bismuth Bi, tungsten W, aluminium Al, copper Cu and indium In, preferably M denotes Si or Al;

[0030] - v denotes the oxidation state of M and is a number between 1 and 8, preference v is less than or equal to 6, and more preferably less than or equal to 4;

[0031] - w is an integer or fractional number ranging from 0 to 20;

[0032] - p is an integer from 1 to 5, preferably p is less than or equal to 3, plus preferably less than or equal to 2, even more preferably equal to 1;

[0033] - q is an integer from 1 to 5, preferably q is less than or equal to at 2, more preferably q is equal to 1; and

[0034] - for each inorganic compound: yv _ qz f [) + Q 5 '

[0035] for UV-A and / or UV-B ray filtration, preferably UV-B, particularly for protecting keratinous materials, especially human ones such as skin, and / or keratinous fibers, especially human ones such as hair;

[0036] it being understood that when b) is TiO2, then the composite material is in the form of “core / shell”.

[0037] Preferably the average size of the largest particle dimension of said composite material is less than or equal to 450 nm.

[0038] Preferably, the average size of the largest dimension of the composite material particle varies from 10 nm to 300 nm, preferably from 25 nm to 250 nm, and more preferably from 40 nm to 200 nm.

[0039] Another object of the invention is a composite material comprising:

[0040] Let i):

[0041] - a core comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 / CO3), as well as its solvates, such as its hydrates, as defined above; and

[0042] - a bark comprising at least b) at least one inorganic compound selected from the oxides and / or hydroxides of formula [(Mfv\.)p OZ(OH),]? (H2O)W formula [(AU-^ O, (OH),]? (H2O)w in which M(v)y, p, z, t, q, and w are as defined previously;

[0043] Either ii):

[0044] - a core comprising at least b) at least one inorganic compound selected from the oxides and / or hydroxides of formula OZ(OH),]? (H2O)W formula Oz (OH),]? (H2O)w in which M(v)y, p, z, t, q, and w are as defined previously;

[0045] - a bark comprising at least a) at least one particle of oxycarbonate of bismuth of formula (I) (BiOj^XCOs), as well as its solvates, such as its hydrates, such as the hydrates as defined above;

[0046] - it being understood that the average size of the largest particle dimension of composite material is less than or equal to 450 nm.

[0047] Surprisingly, and as will be seen from the examples below, the inventors discovered that the composite materials according to the invention exhibit excellent efficiency in filtering ultraviolet radiation, and in particular UV-B rays, as well as high transparency in visible radiation, and allow the composition containing them to have satisfactory cosmetic properties for the consumer.

[0048] For the purposes of the present invention, the term “composite material” means a heterogeneous particulate solid material comprising at least two immiscible components, and the components of which are linked by physical and / or chemical interactions.

[0049] For the purposes of the present invention, the term “high transparency in visible radiation” means particles having a high transmission of rays between 400 and 780 nm.

[0050] 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 0.25, preferably greater than or equal to 0.30, and even more preferably greater than or equal to 0.35. The higher the absorbance threshold, the greater the UV radiation filtration efficiency.

[0051] UV-B radiation refers to the wavelength range from 280 to 320 nm. UV-A radiation refers to the wavelength range from 320 to 400 nm. Visible light refers to the wavelength range from 400 to 780 nm.

[0052] Thus, for the purposes of this invention, "UV filter" means any compound that filters ultraviolet (UV) radiation in the wavelength range from 280 nm to 400 nm. "UV-B filter" means any compound that filters ultraviolet (UV) radiation in the wavelength range from 280 nm to 320 nm. "UV-A filter" means any compound that filters ultraviolet (UV) radiation in the wavelength range from 320 nm to 400 nm.

[0053] To the inventors' knowledge, this efficiency of the composite materials according to the invention is characterized for the first time. It has never been proposed to use composite materials of bismuth oxycarbonate (a), as well as its solvates, such as its hydrates, and inorganic compounds (b), as defined above, for the efficient filtration of UV radiation, in particular UV-B radiation.

[0054] The uses and composite materials 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.

[0055] Thus, according to another aspect, the present invention also relates to the non-therapeutic cosmetic use of a composite material comprising at least a) bismuth oxycarbonate particles of formula (I) (BiO)2XCO3), as well as its solvates, such as its hydrates, wherein -0.4 < % < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one compound in organic as defined above, for filtering UV radiation, preferably UV-B, comprising at least the application to keratin materials, in particular human materials, such as skin and / or keratin fibers, such as hair, said composite material preferably being in a composition, preferably cosmetic.

[0056] The present invention also relates to a non-therapeutic cosmetic process for filtering UV radiation, preferably UV-B, comprising at least the application to keratinous materials of a composition comprising composite materials comprising at least a) bismuth oxycarbonate particles of formula (I) (BiO)2XCO3, as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one inorganic compound as defined above.

[0057] The present invention also relates to methods for preparing composite materials according to the invention.

[0058] By “keratin materials” is meant in particular the skin, including the scalp, the lips, and also keratin fibers such as the hair, the eyelashes, the eyebrows, in particular the skin and / or the hair, and preferably the skin.

[0059] The expression "at least one" is equivalent to "one or more".

[0060] The expressions “between ... and ...”, “includes from ... to ...”, “formed from ... to ...”, and “ranging from ... to ...” must be understood inclusively, unless otherwise specified.

[0061] Other characteristics, variants and advantages of the compositions according to the invention will become more apparent on reading the description and examples which follow. Brief description of the drawings

[0062] [Fig.1] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material A at 0.005 wt% of bismuth oxycarbonate in water.

[0063] [Fig.2] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material B at 0.005 wt% in bismuth oxycarbonate in water.

[0064] [Fig.3] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material C at 0.005 wt% in bismuth oxycarbonate in water.

[0065] [Fig.4] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material D at 0.005 wt% in bismuth oxycarbonate in water.

[0066] [Fig. 5] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material E at 0.005 wt% bismuth oxycarbonate in water.

[0067] [Fig.6] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material F at 0.005% by mass in bismuth oxycarbonate in water.

[0068] [Fig.7] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material G at 0.005% by mass in bismuth oxycarbonate in water.

[0069] [Fig.8] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material H at 0.005% by mass in bismuth oxycarbonate in water.

[0070] [Fig.9] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material I at 0.005% by mass in bismuth oxycarbonate in a Water / Propylene Glycol / Polysorbate 20 mixture.

[0071] [Fig.10] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material J at 0.005 wt% in bismuth oxycarbonate in water.

[0072] [Fig. 11] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of composite material Y outside the invention at 0.005 wt% in bismuth oxycarbonate in water.

[0073] [Fig. 12] represents the absorbance spectrum obtained by UV-visible spectrophotometry on dispersions of Z composite material outside the invention at 0.005 wt% in bismuth oxycarbonate in water. Detailed description

[0074] As stated previously, the composite material comprises at least a) a bismuth oxycarbonate particle, together with its solvates, such as its hydrates, and b) at least one inorganic compound of formula [(M^.),, OZ(OH),]? (H2O)W in which:

[0075] - y is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably y is less than 10, more preferably less than 5, and even more preferably y denotes 1 or 2 or 3;

[0076] - z is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably z is less than 10, more preferably less than 5;

[0077] -1 is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably t is less than 10, more preferably t is less than 5;

[0078] - M is a metal, an alkaline earth metal or a metalloid, preferably chosen among silicon Si, titanium Ti, iron Fe, zinc Zn, niobium Nb, tantalum Ta, cerium Ce, manganese Mn, bismuth Bi, tungsten W, aluminium Al, copper Cu and indium In, preferably M denotes Si or Al;

[0079] - v denotes the oxidation state of M and is a number between 1 and 8, preference v is less than or equal to 6, and more preferably less than or equal to 4;

[0080] - w is an integer or fractional number ranging from 0 to 20;

[0081] - p is an integer ranging from 1 to 5, preferably p is less than or equal to 3, plus preferably less than or equal to 2, even more preferably equal to 1;

[0082] - q is an integer ranging from 1 to 5, preferably q is less than or equal to at 2, more preferably q is equal to 1; and

[0083] - for each inorganic compound: v _ + q

[0084] Thus, the composite material according to the invention can be represented according to the formula [(BiO)2 XCO3]- [(M^^pOXOH),], (H2O)W in which x, M, v, y, p, z, t, q and w are as defined above.

[0085] The average size of the largest dimension of the composite material particle is less than or equal to 450 nm.

[0086] In particular, the average size of the largest dimension of the composite material particle varies from 10 nm to 300 nm, preferably from 25 nm to 250 nm, and more preferably from 40 nm to 200 nm.

[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 dimension "Average" of composite materials 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 or of a particle is its largest dimension observable on a photograph taken in a direction perpendicular to the plane on which said composite material or said particle rests.

[0092] The “width” l and “thickness” e of a composite material or 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 or particle can be inscribed.

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

[0094] The composite materials according to the invention can be of various shapes and structures.

[0095] The composite materials according to the invention may in particular be spherical, cubic, plate-like, cylindrical or tubular.

[0096] The shape of said composite materials will depend in particular on their preparation process and operating conditions.

[0097] In particular, the composite materials according to the invention may be in the form of tubes, platelets, sheets, rods, spheres, flowers, pompoms, threads, filaments, fibers, needles, cubes or any of their mixtures.

[0098] The composite materials according to the invention can furthermore aggregate in the form of superstructures. For example, platelets, tubes and / or rods can aggregate in the form of spheres, flowers or even pompoms.

[0099] According to a particular embodiment, the composite materials according to the invention are in the form of spheres.

[0100] According to a particular embodiment, the composite materials according to the invention are in the form of tubes, plates and / or rods. More preferably, the composite materials according to the invention are in the form of plates and / or rods.

[0101] Composite materials 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.

[0102] It is understood that the composite materials according to the invention can be used in the form of a mixture. In particular, the composite materials according to the invention can be used in a mixture in any proportion of platelets and / or sticks and / or tubes.

[0103] According to a preferred embodiment, the composite materials used according to the invention are found mainly or exclusively in the form of plates.

[0104] A composite material in the form of a "plate" has a length greater than its width and a width greater than its thickness.

[0105] According to a preferred embodiment, the composite materials are found predominantly or exclusively in the form of rods.

[0106] A composite material 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.

[0107] According to a preferred embodiment, the composite materials are found predominantly or exclusively in the form of tubes.

[0108] A composite material in the form of a “tube” has a hollow cylindrical shape and its length L is greater than its diameter d.

[0109] 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 are in the form of plates / sticks / tubes respectively.

[0110] According to one embodiment, the composite material comprises: [YES] Soiti):

[0112] - a core comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 / CO3), as well as its solvates, such as its hydrates, as defined above; and

[0113] - a bark comprising at least b) at least one inorganic compound chosen from the oxides and / or hydroxides of formula [(Mfv\.)p OZ(OH),]? (H2O)W formula [(M^,.),, O, (OH),]? (H2O)w in which M(v)y, p, z, t, q, and w are such as defined previously;

[0114] Soitii):

[0115] - a core comprising at least b) at least one inorganic compound selected from the oxides and / or hydroxides of formula [(Mfv\.)p OZ(OH),]? (H2O)W formula [(M^,.),, O, (OH),]? (H2O)w in which M(v)y, p, z, t, q, and w are such as defined previously;

[0116] - a bark comprising at least a) at least one particle of oxycarbonate of bismuth of formula (I) (BiO)2.x(CO3), as well as its solvates, such as its hydrates, such as the hydrates as defined above;

[0117] - preferably, it being understood that the average size of the largest dimension of particle size of composite material is less than or equal to 450 nm.

[0118] In other words, the composite material comprises:

[0119] - a core comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 / CO3), as well as its solvates, such as its hydrates, wherein -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm, or b) at least one inorganic compound selected from the oxides and / or hydroxides of formula [(Mfv\.)p OZ(OH),]? (H2O)W ; and

[0120] - a bark comprising at least a) at least one particle of oxycarbonate of bismuth of formula (I) (BiO)2 / CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm or b) at least one inorganic compound selected from the oxides and / or hydroxides of formula [(Mfv\.)p OZ(OH),]? (H2O)W;

[0121] in which M(v)y, p, z, t, q, and w are as defined previously,

[0122] it being understood that:

[0123] - said material contains at least one particle a) and at least one compound in organic b); and

[0124] - preferably, the average size of the largest particle dimension of composite material is less than or equal to 450 nm.

[0125] Preferably, the composite material according to the invention comprises:

[0126] - a core comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 XCO3), as well as its solvates, such as its hydrates, as defined above; and

[0127] - a bark comprising at least b) at least one inorganic compound selected from oxides and / or hydroxides of formula [(Mfv\.)p OZ(OH),]? (H2O)W formula [(M^y),, O, (OH),]? (H2O)w in which M(v)y, p, z, t, q, and w are such as defined previously;

[0128] preferably, the average size of the largest dimension of composite material particle being less than or equal to 450 nm.

[0129] According to one embodiment, the composite material according to the invention comprises:

[0130] - a core comprising at least b) at least one inorganic compound selected from the oxides and / or hydroxides of formula [(Mfv\.)p OZ(OH),]? (H2O)W formula [(M^y),, O, (OH),]? (H2O)w in which M(v)y, p, z, t, q, and w are as defined previously; and

[0131] - a bark comprising at least a) at least one particle of oxycarbonate of bismuth of formula (I) (BiO)2 / CO3), as well as its solvates, such as its hydrates, as defined above;

[0132] preferably, the average size of the largest dimension of composite material particle being less than or equal to 450 nm.

[0133] Preferably, the bark is made up of one or more species of inorganic compounds b) chosen from the oxides and / or hydroxides of formula [(Mfv\.)p OZ(OH),]? (H2O)w in which M, v, y, p, z, t, q and w are such as defined above.

[0134] Preferably, the bark is made up of one or more species of inorganic compounds b) chosen from the oxides of formula [(Mfv\.)p OZ(OH),]? (H2O)W in which M, v, y, p, z, t, q and w are such as defined above.

[0135] Preferably, the bark covers all or part of the heart.

[0136] According to a particular embodiment, the molar ratio between the number of moles of compound(s) [(M^^ OZ(OH),]? (H2O)W or respectively [(BiO)2^CO3] constituting the husk and the number of moles of compound constituting the core [(BiO)2^CO3] or respectively [(Mfv\.)p OZ(OH),]? (H2O)w varies from 0.0001 to 20, preferably from 0.005 to 10, better from 0.01 to 5, even better from 0.02 to 2, and even more preferably from 0.05 to 1.

[0137] The bark can consist of a single layer or of several identical or different layers totally or partially superimposed.

[0138] Preferably, the bark consists of a single layer covering all or part of said core.

[0139] According to a particular embodiment, the core-shell composite materials according to the invention contain a majority fraction, namely greater than 50% by number, of composite materials having a core consisting of a single particle of bismuth oxycarbonate (BiO)2CO3, as well as its solvates, such as its hydrates, the largest dimension of which is less than 400 nm.

[0140] According to another particular embodiment, the core-shell composite materials according to the invention contain a majority fraction, namely greater than 50% by number, of composite materials having a core consisting of inorganic oxides [(M OZ(OH),]? (H2O)vv.

[0141] In other words, the core-shell composite materials according to the invention preferably contain a core consisting of a single particle.

[0142] Preferably, the average size of the largest dimension of the core varies from 1 to 400 nm.

[0143] Preferably, the thickness of the bark varies from 1 to 449 nm, preferably from 1 to 300 nm, more preferably from 1 to 200 nm.

[0144] In the context of the uses and methods according to the invention described below, the bismuth oxycarbonate particle(s) a), as well as its solvates, such as its hydrates, and the inorganic compound(s) b) can be arranged in different ways within the composite material.

[0145] According to one embodiment, the composite material may have at least one core and at least one coating in layer(s) surrounding said core.

[0146] Thus, they can comprise at least one coating in layer(s) surrounding a core chemically different from said coating.

[0147] The coating may be formed from one or more layers.

[0148] The core of the composite materials may consist of at least a) one or more particles of bismuth oxycarbonate of formula (I) (BiO)2 / CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm.

[0149] According to a particular embodiment, the core of the composite materials may consist of at least one inorganic compound b).

[0150] The composite material may contain bismuth oxycarbonate particles a) as defined above in the core and / or in the layer(s) forming the coating.

[0151] According to a particular embodiment, the material contains at least one particle of bismuth oxycarbonate a), as well as its solvates, such as its hydrates, as defined above in the core.

[0152] According to another particular embodiment, the material contains particles of bismuth oxycarbonate a), as well as its solvates, such as its hydrates, as defined above in the coating.

[0153] According to one embodiment, the inorganic compound(s) b) may cover all or part of at least one particle of bismuth oxycarbonate a), as well as its solvates, such as its hydrates.

[0154] According to another embodiment, the inorganic compound(s) b) may be covered in whole or in part by at least one particle of bismuth oxycarbonate a), as well as its solvates, such as its hydrates.

[0155] 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 from 0.005 to 10, better still from 0.01 to 5, even better still from 0.02 to 2, and even more preferably from 0.05 to 1.

[0156] According to a particular embodiment, the composite materials according to the invention contain at least one layer surrounding the core.

[0157] Thus, according to a particular embodiment, the composite materials according to the invention comprise a core comprising at least a) at least one bismuth oxycarbonate particle of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, 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 inorganic compound b) as defined above.

[0158] According to a first variant of the invention, the composite materials according to the invention comprise a continuous coating, also called bark or shell, namely surrounding the entire surface of the core.

[0159] According to a second embodiment of the invention, the composite materials conforming to The invention includes a discontinuous coating, also called a bark or shell, namely one that discontinuously surrounds the surface of the core.

[0160] 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.

[0161] According to one embodiment, the coating is a multi-layer coating, i.e. comprising one or more internal layers and an external layer, in other words several superimposed layers for all or part of which each can be continuous or discontinuous.

[0162] In a multi-layer 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.

[0163] In a multi-layer coating, the term "outer layer" means the layer forming the last layer of the coating which is not contiguous to the core. The outer layer is separated from the core by at least one inner layer. The outer layer has no coating.

[0164] In a multi-layer 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.

[0165] In a multi-layer 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.

[0166] The inner layer(s) forming the multi-layer coating of the composite material and the single outer layer of the composite material may be formed from identical or different compounds.

[0167] Each layer can be made up of a single compound or a mixture of compounds.

[0168] The layer or layers may in particular extend concentrically with respect to the core.

[0169] In particular, the composite materials according to the invention have a double layer surrounding the core, in other words an inner layer and an outer layer.

[0170] According to a preferred embodiment, the composite materials according to the invention have at least one layer, preferably comprising at least one inorganic compound b) as defined above.

[0171] According to a preferred embodiment, the composite materials according to the invention comprise:

[0172] - a core comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm, and

[0173] - at least one layer continuously or discontinuously surrounding said core and comprising at least one inorganic compound b) as defined above,

[0174] and the average size of the largest particle dimension of composite material being less than or equal to 450 nm.

[0175] Preferably, the composite materials according to the invention comprise:

[0176] - a core comprising a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm,

[0177] - a single layer contiguous to said core and comprising at least one compound in organic b) as defined above;

[0178] it being understood that the average size of the largest particle dimension of composite material being less than or equal to 450 nm. a) Bismuth oxycarbonate particles

[0179] The bismuth oxycarbonate particles a) according to the invention are of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, with -0.4 < x < 0.6. The value of x can in particular be determined by elemental analysis.

[0180] Preferably, x is equal to 0 and the empirical formula of the bismuth oxycarbonate particles is (BiO)2(CO3), as well as its solvates, such as its hydrates.

[0181] The bismuth oxycarbonate particles according to the invention may be crystallized or amorphous.

[0182] According to one form of the invention, the bismuth oxycarbonate particles a) are amorphous.

[0183] According to a preferred form of the invention, the bismuth oxycarbonate particles a) are crystallized.

[0184] It is understood that the bismuth oxycarbonate particles may consist of a mixture of several bismuth oxycarbonate particles of different empirical formulas and / or different shapes.

[0185] Thus, bismuth oxycarbonate particles can be a mixture of amorphous particles and crystalline particles.

[0186] For the purposes of this invention, "crystallized" means that the atoms constituting the bismuth oxycarbonate particles are arranged in an ordered manner. In other words, the crystallized bismuth oxycarbonate particles are organized materials.

[0187] In contrast, particles whose atoms are disordered are called "amorphous" particles. The atoms of such particles have no organization. the microscopic state.

[0188] Preferably, the crystallized particles required according to the invention have the crystalline phase of the natural bismutite ore, designated as lamellar, and which exhibits an alternation of [Bi2O2]2+ and [CO3]2 layers.

[0189] Such particles crystallize in an orthorhombic space group Imm2 system.

[0190] The bismutite crystal structure of bismuth oxycarbonate can have the following lattice parameters: a = 3.865 Å; b = 3.862 Å; c = 13.675 Å and Vmaiue = 0.204 nm3. This particular arrangement of atoms allows in particular the growth of anisotropic objects.

[0191] A particle is considered "anisotropic" when the elongation factor R between its length L and its thickness e, i.e. R = L / e, is greater than 2.

[0192] According to the invention, the largest average dimension of the crystalline or amorphous particles, preferably crystalline, of bismuth oxycarbonate a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6 is less than 400 nm.

[0193] Preferably, the largest average dimension of said particles is less than or equal to 300 nm.

[0194] According to the invention, bismuth oxycarbonate particles a) of formula (I) (BiO)2 x (CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, can be in any form.

[0195] The shape of said particles will depend in particular on their preparation process and the operating conditions.

[0196] In particular, the particles according to the invention may be in the form of tubes, plates, sheets, rods, spheres, flowers, pompoms, threads, filaments, fibers, needles, cubes or any mixture thereof.

[0197] The particles according to the invention can further aggregate into superstructures. For example, platelets, tubes and / or rods can aggregate into spheres, flowers or pom-poms.

[0198] According to a preferred embodiment, the particles according to the invention are in the form of tubes, plates and / or rods. Even more preferably, the particles according to the invention are in the form of plates and / or rods.

[0199] 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.

[0200] It is understood that the particles according to the invention can be used in the form of a mixture. In particular, the particles according to the invention can be used in a mixture of any proportion of tablets and / or rods and / or tubes.

[0201] According to a preferred embodiment, the particles implemented according to the invention are found predominantly or exclusively in the form of platelets.

[0202] A particle in the form of a "platelet" has a length greater than its width and a width greater than its thickness.

[0203] In particular, when in platelet form, bismuth oxycarbonate particles (a), as well as its solvates, such as its hydrates, possess:

[0204] - an average length L ranging from 15 to 300 nm, in particular ranging from 30 to 250 nm, preferably ranging from 50 to 200 nm, more preferably ranging from 70 to 150 nm;

[0205] - an average width l 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;

[0206] - an average thickness e ranging from 2 to 120 nm, in particular ranging from 5 to 100 nm, preferably ranging from 10 to 80 nm, more preferably ranging from 20 to 50 nm; and

[0207] - with e <1 <L.

[0208] According to a preferred embodiment, the bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, are found predominantly or exclusively in the form of rods.

[0209] 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.

[0210] In particular, when in rod form, whether cylindrical or prismatic, bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, possess:

[0211] - an average length L ranging from 30 to 300 nm, in particular ranging from 50 to 250 nm, preferably ranging from 70 to 230 nm, more preferably ranging from 70 to 140 nm;

[0212] - an average diameter d ranging from 15 to 150 nm, in particular ranging from 20 to 130 nm, of preferably ranging from 25 to 120 nm, more preferably from 25 to 100 nm, and even more preferably from 25 to 60 nm, and

[0213] -withL>d.

[0214] According to a preferred embodiment, the bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, are found predominantly or exclusively in the form of tubes.

[0215] A particle in the form of a “tube” has a hollow cylindrical shape and its length L is greater than its diameter d.

[0216] In particular, when in tube form, the oxycarbonate particles of Bismuth, as well as its solvates, such as its hydrates, possess:

[0217] - an average length L ranging from 10 to 300 nm, in particular ranging from 20 to 250 nm, preferably ranging from 40 to 200 nm, more preferably ranging from 60 to 200 nm;

[0218] - an average diameter d ranging from 2 to 30 nm, in particular ranging from 3 to 20 nm, and of preferably ranging from 5 to 15 nm; and

[0219] -withL>d.

[0220] By "predominantly in the form of platelets / rods / tubes" within the meaning of the present invention, it is meant that at least 50% by number, in particular at least 70% by number, or even at least 90% by number of the particles are in the form of platelets / rods / tubes respectively. Doping of particles a)

[0221] According to a particular embodiment, the bismuth oxycarbonate particles a), as well as its solvates, such as its hydrates, can be doped.

[0222] In particular, bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, can be doped with one or more chemical elements capable of inserting themselves into the structure or partially substituting for elements already present.

[0223] The particles can be doped via substitutions of all or part of the cations and / or all or part of the anions.

[0224] 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.

[0225] 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%.

[0226] In particular, bismuth oxycarbonate 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).

[0227] Preferably, the bismuth oxycarbonate 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.

[0228] According to one embodiment, the bismuth oxycarbonate particles a) are doped with cations from manganese, and the doping rate varies in particular from 0.5% to 2%.

[0229] According to another embodiment variant, the bismuth oxycarbonate particles are doped with cations derived from iron, and the doping rate varies in particular from 0.5% to 2%.

[0230] According to another particular embodiment, the doping relates in part or in whole to anions inserted or substituted for the carbonate group within the limit of 20% of the carbonate composition.

[0231] 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%.

[0232] In particular, the bismuth oxycarbonate particles a) may be doped with anions derived from elements chosen from fluorine (F), sulfur (S), chlorine (Cl), bromine (Br), iodine (I), and / or with polyatomic anions, in particular chosen from sulfate ion (SO42), sulfonate ion (S(=0)2-0), sulfite ion (SO32), phosphate ion (PO43) and / or iodate ion (IO3).

[0233] Preferably, the bismuth oxycarbonate particles a) can be doped with S2, SO32, SO42, Cl and / or I, more preferably with SO32, SO42 and / or Cl, and more preferably with Cl or SO42.

[0234] According to one embodiment, the bismuth oxycarbonate particles a) are doped with chlorine anions, and the doping rate varies in particular from 0.01% to 0.1%.

[0235] According to another embodiment, the bismuth oxycarbonate particles are doped with iodine anions, and the doping rate varies in particular from 0.003% to 0.01%.

[0236] According to another embodiment, the bismuth oxycarbonate particles a) are doped with the sulfate ion, and the doping rate varies in particular from 0.005% to 0.1%.

[0237] According to another embodiment, the bismuth oxycarbonate particles a) are doped with cations preferably 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, and with anions preferably from elements selected from fluorine (F), sulfur (S), chlorine (Cl), bromine (Br), iodine (I), 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, Cl and / or I, even more preferably with SO32, SO42 and / or Cl, and particularly preferred with Cl, I or SO42.

[0238] According to a preferred embodiment, the bismuth oxycarbonate particles a), as well as its solvates, such as its hydrates, required according to the invention are undoped.

[0239] According to another preferred embodiment, the bismuth oxycarbonate particles a), as well as its solvates, such as its hydrates, required according to the invention are doped.

[0240] According to another preferred embodiment, the bismuth oxycarbonate particles a), as well as its solvates, such as its hydrates, required according to the invention are a mixture of doped particles and undoped particles.

[0241] Process for preparing bismuth oxycarbonate particles a)

[0242] Bismuth oxycarbonate particles a), as well as its solvates, such as its hydrates, can be obtained by any preparation process known to those skilled in the art.

[0243] For example, the synthesis of bismuth oxycarbonate particles is described in the article by Ni et al. (Fabrication, modification and application of (BiO)2CO3-based photocatalysts: A review, Applied Surface Science, 365, 2016, 314-335).

[0244] In particular, bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, can be prepared by solvothermal, electrochemical, co-precipitation, or reflux methods, and preferably by solvothermal or reflux methods.

[0245] According to a first embodiment, bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, are obtained by solvothermal means, in particular from bismuth nitrate and various carbonating agents such as sodium carbonate, ammonium carbonate, or urea, in a polar protic solvent in the presence of polyols. Such a synthesis allows the production of bismuth oxycarbonate particles in the form of platelets and / or rods, the largest dimension of which varies from 50 to 300 nm.

[0246] La synthèse des particules par voie solvothermale est notamment décrite dans les articles de Cheng, G. et al. (Shape-controlled solvothermal synthesis of bismuth subcarbonate nanomaterials, J. Solid State Chem. 183, 1878-1883 (2010)) ; Ruan, MM et al. (Facile Green Synthesis of Highly Monodisperse Bismuth Subcarbonate Micropompons Self-assembled by Nanosheets: Improved Photocatalytic Performance, Acta Physico-Chimica Sinica, 33, 2017, 1033-1042) ; Quin et al. (Template-Free Fabrication of Bi2O3 and (BiO)2CO3 Nanotubes and Their Application in Water Treatment, Chem. Eur. J., 18, 2012, 16491-16497) ; Cheng, G. et al. (Shape-controlled solvothermal synthesis of bismuth subcarbonate nanomaterials, J. Solid State Chem., 183, 2010, 1878-1883) ; Liu, YY et al. (Préparation, electronic structure, and photocatalytic properties of Bi2O2CO3 nanosheet, Appl. Surf. Sci., 257, 2010, 172-175) ; Zheng et al. (Synthetic Bi2O2CO3 nanostructures: Novel photocatalyst with controlled special surface exposed, Journal of Molecular Catalysis A: Chemical, 2010, 317 (1-2), 34-40); Liu, SQ et al. (The effects of citrate ion on morphology and photocatalytic activity of flower-like Bi2O2CO3, Ceram. Int., 40, 2014, 2343-2348); or Chen, R. et al. (Bismuth subcarbonate nanoparticles fabricated by water-in-oil microemulsion-assisted hydrothermal process exhibit anti-Helicobacterpylori properties, Mater. Res. Bull., 45, 2010, 654-658).

[0247] The synthesis of particles by electrochemical means is notably described in the article by Hu, Y. et al. (Simple hydrolysis route to synthesize Bi2O2CO3 nanoplate from Bi nanopowder and its photocatalytic application, Materials Letters, 170, 2016, 72-75).

[0248] The synthesis of particles by co-precipitation is notably described in the article by Chen, XY et al. (Controlled synthesis of bismuth oxo nanoscalecrystals (BiOCl, Bii2O i7Cl2, a-Bi2O3, and (BiO)2CO3) by solution-phase methods, J. Solid State Chem., 180, 2007,2510-2516).

[0249] The synthesis of particles by reflux is notably described in the article by Chen et al. (Fabrication of bismuth subcarbonate nanotube arrays from bismuth citrate, Chem. Commun., 2006, 2265-2267).

[0250] According to a preferred embodiment, the bismuth oxycarbonate particles required according to the invention are obtained by solvothermal means, for example according to the method described by Cheng et al., or by reflux, for example according to the method described by Chen et al..

[0251] According to a preferred embodiment, the bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, required according to the invention are obtained by a preparation process using one or more bismuth(III) complexes, one or more carbonating agents, one or more polyols and optionally one or more polar solvents, distinct from the polyols.

[0252] When the particles used according to the invention are doped, one or more additional reagents including the doping elements may be added.

[0253] In particular, the bismuth(III) complex(s) is / are selected from 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.

[0254] The bismuth(III) complex(es) may also be obtained from bismuth minerals, such as elemental bismuth and / or bismuth oxide and / or bismuth sulfide.

[0255] Preferably, the bismuth(III) complex(es) is(are) bismuth(III) nitrate and its hydrated forms of formula Bi(NO3)3%H2O, and preferably is bismuth nitrate pentahydrate of formula Bi(NO3)3-5H2O.

[0256] In particular, the carbonating agent(s) is (are) chosen from Li2CO3, Na2CO3, K2CO3, Rb2CO3, Cs2CO3, (NH4)2CO3, LiHCO3, NaHCO3, KHCO3, RbHCO3, CsHCO3, (NH4)HCO3, urea (NH2)2CO and urea derivatives, CO2, preferably from Na2CO3, K2CO3, (NH2)2CO, (NH4)2CO3, and more preferably from (NH2)2CO and / or (NH4)2CO3.

[0257] Polyols are compounds having several hydroxyl functions. They may in particular be chosen from glycols, in particular ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol; short or long polymers of glycols, for example polyethylene glycol, polypropylene glycol, polybutylene glycol; glycerol and its derivatives; or for example sugars, in particular glucose, fructose, sucrose, xylitol, mannitol, such as D-mannitol, sorbitol or maltitol.

[0258] According to one embodiment, the bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, required according to the invention are obtained by a preparation process using a polyol or a mixture of polyols.

[0259] According to a first embodiment variant, the polyol(s) may also be used as a solvent. The bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, may then be obtained for example according to the process described below.

[0260] A solution A is formed from the dissolution of the bismuth (III) complex, preferably at a concentration of 0.001 to 0.5 M, in the polyol or polyol mixture. A solution B is formed by the partial or complete dissolution of the carbonating agent, preferably from 1 to 100 equivalents relative to bismuth, in the polyol or polyol mixture or in a polyol or polyol mixture different from that(those) used in solution A.

[0261] In the case of doping by a cation, the doping agent is preferably integrated into solution A. In the case of doping by an anion, the doping agent is preferably integrated into solution B.

[0262] In the case of doping by one or more cation(s) and / or by one or more anion(s), the cationic doping agent(s) is / are preferably integrated into solution A and the anionic doping agent(s) is / are preferably integrated into solution B. Solution A is then added at room temperature to solution B. If the polyol or the mixture of polyols is not liquid at room temperature, all the solids are mixed.

[0263] The resulting mixture is then heated to between 90 and 250 °C for a reaction time of between 10 minutes and 48 hours. If the desired reaction temperature is greater than or equal to the boiling point of the solvent, a solvothermal synthesis is carried out using an autoclave.

[0264] Preferably, the reaction temperature is between 95 °C and 200 °C and the reaction time is between 1 and 24 hours, and more preferably the reaction temperature is between 100 °C and 180 °C and the reaction time is between 2 and 16 hours.

[0265] The particles obtained are isolated from the reaction medium by centrifugation and washed by successive cycles of dispersion and centrifugation.

[0266] After drying under vacuum at a temperature between 40°C and 60°C, a white powder is obtained.

[0267] In the case where the polyol(s) are used as solvents, the resulting bismuth oxycarbonate particles are in the form of platelets, preferably with an average thickness e between 2 and 15 nm, and / or in the form of tubes.

[0268] According to another embodiment variant, the polyol(s) are used solely as additives, and not as solvents. The bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, can then be obtained for example according to the process described below.

[0269] A solution A is formed from the dissolution of the bismuth complex, preferably at a concentration of 0.001 to 0.5 M, and the polyol(s) preferably at a total concentration of polyols, preferably 0.01 to 5 M, in a solvent, preferably polar. A solution B is formed by the partial or complete dissolution of the carbonating agent, preferably 1 to 100 equivalents relative to the bismuth complex, in the polar solvent identical or different (miscible with the solvent of A) from that of solution A, preferably identical.

[0270] In the case of doping with a cation, the doping agent is preferably incorporated into solution A. In the case of doping with an anion, the doping agent is preferably incorporated into solution B.

[0271] In the case of doping by one or more cation(s) and / or by one or more anion(s), the cationic doping agent(s) is / are preferably integrated into solution A and the anionic doping agent(s) is / are preferably integrated into solution B.

[0272] Solution A is then added at room temperature to solution B. The resulting mixture is then heated to between 90 °C and 250 °C for 10 minutes to 48 hours. If the desired reaction temperature is greater than or equal to the boiling point of the solvent, a solvothermal synthesis is carried out using an autoclave.

[0273] Preferably, the reaction temperature is between 90 °C and 150 °C and the reaction time is between 4 and 16 hours.

[0274] The particles obtained are isolated from the reaction medium by centrifugation and washed by successive cycles of dispersion and centrifugation.

[0275] After drying under vacuum at a temperature between 40°C and 60°C, a white powder is obtained.

[0276] When the polyol(s) are used solely as additives, they may in particular be selected from ethylene glycol, propylene glycol, glycerol and / or a sugar, preferably a sugar, more preferably D-mannitol.

[0277] According to this variant, the synthesis process further employs a solvent distinct from the polyols, or a mixture of solvents distinct from the polyols. In particular, the solvent or mixture of solvents is chosen from polar solvents, preferably from polar and protic solvents, such as water; Ci-C6 alcohols such as ethanol or isopropanol; and mixtures thereof, and even more preferably the solvent is water.

[0278] In particular, when the polyol(s) are chosen solely as additives and water as solvent, the particles of bismuth oxycarbonate, as well as its solvates, such as its hydrates, obtained are preferably in the form of platelets and / or in the form of rods. Inorganic compound b)

[0279] The composite material according to the invention comprises at least one inorganic compound b) of formula [(M^ OZ(OH),]? (H2O)W in which:

[0280] - y is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably less than 10, more preferably less than 5, and even more preferably denotes 1 or 2 or 3;

[0281] - z is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably z is less than 10, more preferably less than 5;

[0282] -1 is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably t is less than 10, more preferably t is less than 5;

[0283] - M is a metal, an alkaline earth metal or a metalloid, preferably chosen among silicon Si, titanium Ti, iron Fe, zinc Zn, niobium Nb, tantalum Ta, cerium Ce, manganese Mn, bismuth Bi, tungsten W, aluminium Al, copper Cu and indium In, more preferentially chosen among silicon Si, iron Fe, zinc Zn, niobium Nb, tantalum Ta, cerium Ce, manganese Mn, bismuth Bi, tungsten W, aluminium Al, copper Cu and indium In, particularly chosen among silicon Si, iron Fe, zinc Zn, niobium Nb, tantalum Ta, cerium Ce, manganese Mn, bismuth Bi, aluminium Al, copper Cu and indium In, better M designates Si or Al;

[0284] - v denotes the oxidation state of M and is a number between 1 and 8, of preference v is less than or equal to 6, and more preferably less than or equal to 4;

[0285] - w is an integer or fractional number from 0 to 20;

[0286] - p is an integer from 1 to 5, preferably p is less than or equal to 3, plus preferably less than or equal to 2, even more preferably equal to 1;

[0287] - q is an integer from 1 to 5, preferably q is less than or equal to at 2, more preferably q is equal to 1; and

[0288] - for each inorganic compound: yp _ pz + 0 5'

[0289] The term "inorganic oxides" means amorphous or crystalline forms, hydrated or non-hydrated, of oxides or hydroxides or oxy-hydroxides of alkali or alkaline earth metals, in particular sodium, potassium, magnesium and calcium, or of transition metals, in particular titanium, aluminium, manganese, iron, copper, niobium and tantalum, in particular aluminium, manganese, iron, copper, niobium and tantalum, or of lanthanides, in particular cerium, or of post-earth metals, in particular zinc, indium and bismuth.

[0290] Inorganic oxides may also refer to amorphous or crystalline forms, hydrated or non-hydrated, of oxides or hydroxides or oxy-hydroxides of metalloids. In particular, the inorganic oxides according to the invention may be amorphous or crystalline forms, hydrated or unhydrated, of oxides or hydroxides or oxy-hydroxides of silicon such as silica SiO2, clays such as kaolinite, montmorillonite, illite, or hectorite, lithium and / or sodium and / or potassium 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.

[0291] As examples of metal oxides [(M^^^O^OH),], (H2O)„„, hydrated and non-hydrated forms of Al2O3, Al(OH)3, SiO2, TiO2, MnO, MnO2, FeO(OH), Fe3O4, Fe2O3, Cu(OH)2, Cu2O, CuO, Zn(OH)2, ZnO, Nb2O5, In(OH)3, In2O3, Ce2O3, CeO2, Ta2O5, WO3, Bi2O3, and mixtures thereof may be cited. More particularly, as examples of metal oxides [(M^.^OXOH),], (H2O)W, hydrated and non-hydrated forms of Al2O3 such as Al(OH)3, SiO2, MnO, MnO2, FeO(OH), Fe3O4, Fe2O3, Cu(OH)2, Cu2O, CuO, Zn(OH)2, ZnO, Nb2O5, In(OH)3, In2O3, Ce2O3, CeO2, Ta2O5, WO3, Bi2O3, and mixtures thereof.

[0292] More particularly, as metal oxides [(M^^^O^OH),], (H2O)VV, mention may be made of the hydrated or non-hydrated forms of Al2O3 such as A1(OH)3, SiO2, MnO, MnO2, FeO(OH), Fe3O4, Fe2O3, Cu(OH)2, Cu2O, CuO, Zn(OH)2, ZnO, Nb2O5, In(OH)3, In2O3, Ce2O3, CeO2, Ta2O5, Bi2O3, as well as their mixtures.

[0293] Preferably, the hydrated or non-hydrated forms of Al2O3, SiO2, TiO2, Fe2O3, ZnO, Nb2O5, In2O3, CeO2, Bi2O3 and their mixtures will be used, more preferably the forms hydrated or not of Al2O3, SiO2, TiO2, Fe2O3, ZnO and their mixtures, and even more preferably the hydrated or not forms of Al2O3, SiO2 and their mixtures.

[0294] More particularly, hydrated or non-hydrated forms of Al2O3, SiO2, Fe2O3, ZnO, Nb2O5, In2O3, CeO2, Bi2O3 and their mixtures will be used, more preferably hydrated or non-hydrated forms of Al2O3, SiO2, Fe2O3, ZnO and their mixtures, and even more preferably hydrated or non-hydrated forms of Al2O3, SiO2 and their mixtures.

[0295] Preferably [(M^-^ OZ(OH),]? (H2O)w is different from TiO2

[0296] According to a first particular embodiment, q is equal to 1 and p is equal to 1.

[0297] According to this embodiment, preferably M denotes aluminum Al, silicon Si, titanium Ti, manganese Mn, iron Fe, copper Cu, zinc Zn, niobium Nb, indium In, cerium Ce, tantalum Ta, tungsten W and bismuth Bi.

[0298] Preferably, M denotes Si, Ti, Fe, Zn or Bi, and more preferably Si, Ti, Zn, better Si.

[0299] According to one embodiment M is different from Ti.

[0300] Preferably, M denotes Si, Fe, Zn or Bi, and more preferably Si, Zn, better Si.

[0301] According to a second embodiment, q is equal to 1 and p is greater than 1.

[0302] According to this embodiment, q is equal to 1 and preferably p is greater than 1 and less than or equal to 3, more preferably p is equal to 2.

[0303] Preferably, at least one of the Ms is chosen from aluminium Al, silicon Si, titanium Ti, manganese Mn, iron Fe, copper Cu, zinc Zn, niobium Nb, indium In, cerium Ce, tantalum Ta, tungsten W, and bismuth Bi, and, more preferably, chosen from Si, Ti, Fe, Zn, Bi, and even more preferably chosen from Si, Ti and Zn.

[0304] More particularly, at least one of the Ms is chosen from aluminium Al, silicon Si, manganese Mn, iron Fe, copper Cu, zinc Zn, niobium Nb, indium In, cerium Ce, tantalum Ta, tungsten W, and bismuth Bi, and, more preferably, chosen from Si, Fe, Zn, Bi, and even more preferably chosen from Si and Zn

[0305] Preferably, at least one of the M is an alkali or alkaline earth metal, preferably selected from Na, K, Mg, Ca.

[0306] According to another embodiment, q is greater than 1, and preferably q is equal to 2.

[0307] According to this embodiment, at least one of the M is chosen from aluminum Al, silicon Si, titanium Ti, manganese Mn, iron Fe, copper Cu, zinc Zn, niobium Nb, indium In, cerium Ce, tantalum Ta, tungsten W and bismuth Bi.

[0308] Preferably, M denotes Si, Ti, Fe, Zn or Bi, and more preferably Si, Ti, Zn, compounds b) being able to further contain at least one alkali or alkaline-earth metal preferably chosen from Na, K, Mg and Ca. Composite material preparation process

[0309] The composite materials according to the invention can in particular be obtained according to the preparation methods described below.

[0310] In particular, the composite materials according to the invention as defined above can be obtained in one or more stages.

[0311] In particular, the composite materials according to the invention can be obtained from pre-formed bismuth oxycarbonate particles a) obtained in particular by the processes as described above.

[0312] According to a particular embodiment, the process for preparing composite materials according to the invention uses pre-formed bismuth oxycarbonate particles a) and may include one or more separation and / or heat treatment steps.

[0313] In particular, such a method for preparing composite materials according to the invention implements:

[0314] - at least one particle of bismuth oxycarbonate a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm;

[0315] - optionally one or more precursors intended to form the compound(s) b) as previously described;

[0316] - optionally one or more additives; and

[0317] - optionally one or more solvents.

[0318] According to a particular embodiment, the process for preparing composite materials according to the invention uses pre-formed particles made up of one or more inorganic compounds b) and may include one or more separation and / or heat treatment steps.

[0319] In particular, such a method for preparing composite materials according to the invention implements:

[0320] - at least one precursor of bismuth oxycarbonate particles a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm;

[0321] - at least one carbonating agent;

[0322] - possibly one or more additives; and

[0323] - possibly one or more solvents.

[0324] The precursors of bismuth oxycarbonate particles a) according to the invention, as well as its solvates, such as its hydrates, are in particular selected from the soluble complexes of bismuth (III), more particularly bismuth nitrate and its hydrated forms, bismuth citrate and its hydrated forms, bismuth sulfate and its hydrated forms, bismuth chloride and its hydrated forms.

[0325] The bismuth(III) complex(es) may in particular be obtained from bismuth minerals such as elemental bismuth and / or bismuth oxide and / or bismuth sulfide.

[0326] The carbonating agent(s) are in particular chosen from Li2CO3, Na2CO3, K2 CO3, Rb2CO3, Cs2CO3, (NH4)2CO3, LiHCO3, NaHCO3, KHCO3, RbHCO3, CsHCO3, (NH4)HCO3, urea (NH2)2CO and urea derivatives, CO2.

[0327] The organic or inorganic precursors, hydrated or not, of the compounds containing at least one element M are in particular chosen from solubilized oxides such as sodium aluminates or silicates, halides and their hydrated versions, nitrates and their hydrated versions, carbonates and their hydrated versions, sulfonates and their hydrated versions, sulfates and their hydrated versions, phosphates and their hydrated versions, and / or organometallic precursors and their hydrated versions, in particular alkoxides and their hydrated versions, carboxylates and their hydrated versions, lactates and their hydrated versions, citrates and their hydrated versions.

[0328] According to a particular embodiment, the process for preparing composite materials according to the invention uses at least one additive.

[0329] In particular, any additives used depend on the synthesis process and may be chosen from acids, bases, oxidants, reducers and / or any reagent necessary for the precipitation of species and / or their adhesion.

[0330] In particular, the additive(s) may be chosen from acids, in particular mineral acids, such as hydrochloric acid or sulfuric acid, and bases, preferably mineral, such as sodium hydroxide or potassium hydroxide.

[0331] In particular, the additives may include one or more organic and / or inorganic additives necessary for the reactions to obtain the inorganic compound(s) b), and may therefore include in particular oxidizing precursors, in particular air, hydrogen peroxide, peroxides and their hydrated versions.

[0332] Any additives required for precipitation and / or adhesion may be surfactants such as sodium dodecyl sulfate and sugars such as mannitol or glucose.

[0333] According to a particular embodiment, the process for preparing composite materials according to the invention uses at least one solvent.

[0334] The choice of solvent(s) may in particular depend on the precursor(s) and additive(s) used in the process.

[0335] In particular, the solvent(s) may be chosen from polar and / or nonpolar, protic and / or aprotic solvents.

[0336] Preferably, the solvent used is a polar and protic solvent, in par- a particular one chosen from among water, alcohols, polyols and their mixtures.

[0337] Preferably, the solvent used is water.

[0338] According to a particular embodiment, the method for preparing the materials composites according to the invention may comprise one or more separation steps, for example by filtration and / or centrifugation.

[0339] According to a particular embodiment, the process for preparing composite materials according to the invention may include one or more heat treatment steps, carried out with or without solvent, under an inert atmosphere or not, for example at temperatures ranging from 50 °C to 1200 °C, in particular to remove solvents and / or other residual volatile molecules from the materials and / or to induce a transformation, such as dehydration or crystallization.

[0340] According to a preferred embodiment, the preparation process according to the invention uses pre-formed bismuth oxycarbonate particles a) to form the core of said composite material.

[0341] According to a preferred embodiment, the preparation process according to the invention uses a single inorganic compound b) to constitute the shell of the composite particles, and preferably the inorganic compound b) is chosen from silica and titanium dioxide, and more preferably is silica.

[0342] According to these embodiments, the composite materials can be obtained by precipitation on the core: - of one or more silicon tetraalkoxides, preferably in C2-C4, such as tetraethylorthosilicate or tetrapropylorthosilicate, in particular according to 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); - 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 C2-C4 titanium alkoxides, and in particular titanium tetraisopropoxide.

[0343] According to another preferred embodiment, the preparation process according to the invention uses pre-formed particles of at least one inorganic compound b), preferably silica, to form the core of said composite material, and the bark is made up of bismuth oxycarbonate a), as well as its solvates, such as its hydrates.

[0344] According to this embodiment, the composite materials can in particular be obtained by precipitation of bismuth nitrate pentahydrate using ammonium carbonate on the core of inorganic compound(s) b).

[0345] According to a particular embodiment, the present invention relates to a method of preparation of composite materials as defined above, including the steps consisting of:

[0346] (i) have a dispersion of bismuth oxycarbonate particles a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension 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;

[0347] (ii) have an aqueous solution of sodium silicate b), 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;

[0348] (iii) bringing together said dispersion (i) and said solution (ii) to form the composite material;

[0349] (iv) insulating said composite material.

[0350] In particular, the solvent or solvents of step (i) is chosen from polar and protic solvents, more preferably from water, alcohols, polyols and mixtures thereof, and even more preferably from water.

[0351] According to a particular embodiment, the medium of the dispersion (i) can be heated to reflux, preferably to a temperature less than or equal to 100°C.

[0352] According to a particular embodiment, the solution (ii) can be heated to reflux, preferably to a temperature of 100 °C, before mixing in step (iii).

[0353] According to a particular embodiment, the aqueous sodium silicate solution b) is in an amount ranging from 0.05 g / L to 500 g / L.

[0354] According to a particular embodiment, the pH in step (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.

[0355] According to a particular embodiment, step (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.

[0356] According to a particular embodiment, a cooling step can be carried out between steps (iii) and (iv).

[0357] According to a particular embodiment, step (iv) can be carried out by centrifugation.

[0358] According to a particular embodiment, step (iv) 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).

[0359] According to a particular embodiment, the present invention relates to a process for preparing composite materials as defined above, comprising the steps of:

[0360] (1) have a dispersion of bismuth oxycarbonate particles a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension 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;

[0361] (1') adding a basic aqueous solution, preferably aqueous ammonia to said dispersion (1);

[0362] (2) having a solution of at least one silicon tetraalkoxide b);

[0363] (3) bringing together said dispersion (1') and said solution (2) to form the composite material;

[0364] (4) isolate said composite material.

[0365] In particular, the solvent(s) of step (1) is 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 b) or corresponding to one of the alkoxide groups in the case of use of a mixture of silicon tetraalkoxides b).

[0366] According to a particular embodiment, the dispersion medium (1) can be heated until reflux of the medium, preferably at a temperature between 50 °C and 70 °C.

[0367] According to a particular embodiment, the medium is maintained at this temperature throughout the duration of the reaction.

[0368] According to a particular embodiment, the molar ratio in step (3) ammonia / silicon varies from 0.005 to 50, more preferably from 0.1 to 5.

[0369] According to a particular embodiment, the molar ratio in step (3) 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.

[0370] According to a particular embodiment, step (3) is carried out for a period of 15 minutes to 48 hours, preferably from 30 minutes to 24 hours and more preferably from 1 hour to 8 hours.

[0371] According to a particular embodiment, a cooling step can be carried out between steps (3) and (4).

[0372] According to a particular embodiment, step (4) can be carried out by centrifugation.

[0373] According to a particular embodiment, step (4) is followed by a washing step, in particular by successive cycles, and possibly 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).

[0374] According to a particular embodiment, the present invention relates to a process for preparing composite materials as defined above, comprising the steps consisting of:

[0375] (a) have a dispersion of bismuth oxycarbonate particles a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension 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;

[0376] (a') optionally add a basic aqueous solution, preferably of hydroxide of sodium, preferably of pH ranging from 8 to 13, and more preferably from 9 to 12, to said dispersion (a);

[0377] (b) have a solution of at least one titanium tetraalkoxide b), possibly in at least one solvent, in particular in a Ti / Bi molar ratio ranging from 0.001 to 2, more preferably from 0.01 to 1.5, and more preferably from 0.1 to 1;

[0378] (c) bringing said dispersion (a') and said solution (b) into contact to form the composite material;

[0379] (d) insulating said composite material.

[0380] In particular, the solvent(s) of step (a) and (b) may be identical or different, preferably identical, and preferably chosen from polar and protic solvents, more preferably from alcohols, and even more preferably is an alcohol corresponding to the alkoxide group of titanium tetraalkoxide b) or corresponding to one of the alkoxide groups in the case of using a mixture of titanium tetraalkoxides b).

[0381] According to a particular embodiment, the dispersion medium (a) can be heated until reflux of the medium, preferably at a temperature between 20 °C and 50 °C.

[0382] According to a particular embodiment, the medium is maintained at this temperature throughout the duration of the reaction.

[0383] According to a particular embodiment, the solution of at least one titanium tetraalkoxide b), is in an amount ranging from 0.05 g / L to 500 g / L.

[0384] According to a particular embodiment, step (c) is carried out for a period of 5 minutes to 48 hours, preferably from 15 minutes to 24 hours and more preferably from 30 minutes to 8 hours.

[0385] According to a particular embodiment, a cooling step can be carried out between steps (c) and (d).

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

[0387] According to a particular embodiment, step (d) 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). Cosmetic composition

[0388] The composite materials according to the invention can in particular be used in a composition, especially in a cosmetic composition.

[0389] Thus, the present invention also relates to a composition, in particular a cosmetic composition, comprising at least one composite material as defined above.

[0390] According to a preferred embodiment, the present invention also relates to a composition, in particular a cosmetic composition, comprising at least:

[0391] i) at least one composite material as defined above;

[0392] ii) at least one aqueous phase and / or at least one fatty phase; and

[0393] iii) at least one compound chosen from: 1) UV filters distinct from the materials composites i); 2) coloring matters; 3) cosmetic active ingredients for the care of keratin materials; 4) surfactants; 5) thickeners; and their mixtures.

[0394] Said composite materials may be present in the composition, preferably cosmetic, in a content ranging from 0.5% to 70% by weight, preferably from 1% to 50% by weight, even better from 2% to 40% by weight relative to the total weight of the composition. Aqueous phase

[0395] A composition, in particular a cosmetic one, according to the invention may comprise at least one aqueous phase.

[0396] The aqueous phase may include water and optionally a water-soluble solvent.

[0397] 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).

[0398] The water-soluble solvents usable in a composition according to the invention may also be volatile.

[0399] Among the water-soluble solvents which may be used in a composition in accordance with the invention, mention may in particular be made of lower monoalcohols having from 1 to 5 carbon atoms such as ethanol and isopropanol, C2-C32 polyols, C3 and C4 ketones and C2-C4 aldehydes.

[0400] Among the water-soluble solvents that can be used in a composition in accordance with the invention, mention may in particular be made of polyols. By "polyol", it is meant, for the purposes of the present invention, any organic molecule comprising at least two free hydroxyl groups.

[0401] A polyol suitable for the invention may be a compound of alkyl type, linear, branched or cyclic, saturated or unsaturated, carrying on the alkyl chain at least two -OH functions, in particular at least three -OH functions.

[0402] 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 3 to 16 carbon atoms.

[0403] Advantageously, the polyol can be chosen for example from pentaerythritol, trimethylolpropane, caprylyl glycol, glycerol, polyglycerols, such as glycerol oligomers like diglycerol, polyethylene glycols, polypropylene glycols, and mixtures thereof. Fatty phase

[0404] A composition, in particular a cosmetic one, according to the invention may further comprise at least one oily phase, in particular an oily phase.

[0405] 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.

[0406] Preferably, the oily phase comprises at least one oil, in particular a cosmetic oil.

[0407] By "oil" is meant a non-aqueous compound, immiscible with water, liquid at room temperature (25 °C) and atmospheric pressure (760 mm Hg).

[0408] The oily phase may comprise at least one volatile or non-volatile hydrocarbon oil and / or a fat.

[0409] As non-volatile hydrocarbon oils, mention may in particular be made of hydrocarbon oils of vegetable origin, synthetic ethers having from 10 to 40 carbon atoms, linear or branched hydrocarbons, of mineral or synthetic origin, synthetic esters, fatty alcohols which are liquid at room temperature with a branched and / or unsaturated carbon chain having from 12 to 26 carbon atoms, higher fatty acids in C12-C22, carbonates, and mixtures thereof.

[0410] As volatile hydrocarbon oils, mention may in particular be made of hydrocarbon oils having from 8 to 16 carbon atoms.

[0411] Non-volatile silicone oils may be selected, in particular, from among non-volatile polydimethylsiloxanes (PDMS) and phenylened silicones. Examples of volatile silicone oils include, for example, volatile linear or cyclic silicone oils.

[0412] Fluorinated volatile oils, such as nonafluoromethoxybutane, nonafluoromethoxybutane, decafluoropentane, tetradecafluorohexane, dodecafluoropentane and mixtures thereof, may also be used.

[0413] The oil phase may further comprise, mixed with or solubilized in the oil, other fats. Another fat that may be present in the oil phase may be, for example, a fatty acid, a wax, a gum, a paste compound, or mixtures thereof. 1) Additional UV filters

[0414] According to a particular embodiment, a composition according to the invention comprises 1) at least one complementary UV filter separate from the composite materials required according to the invention and defined above.

[0415] By "separate complementary UV filter from composite materials", for the purposes of the present invention, means any UV filter whose chemical nature differs from that of the composite materials required according to the invention and defined above.

[0416] The composite materials 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.

[0417] Thus, the cosmetic composition may also contain one or more additional UV filters chosen from among hydrophilic, lipophilic or insoluble organic UV filters and / or mineral UV filters, different from the composite materials according to the invention.

[0418] By "hydrophilic UV filter" is meant any organic or inorganic cosmetic or dermatological 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.

[0419] By "lipophilic UV filter" is meant any organic or inorganic cosmetic or dermatological 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.

[0420] By "insoluble UV filter" is meant any organic or inorganic cosmetic or dermatological 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®. 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 evaluated in the laboratory.

[0421] The complementary organic UV filters are notably chosen from:

[0422] - cinnamic compounds, in particular Ethylhexyl Methoxycinnamate,

[0423] - anthranilate compounds, in particular Menthyl anthranilate,

[0424] - salicylic compounds, in particular Homosalate and Ethylhexyl Salicylate,

[0425] - dibenzoylmethane compounds, in particular Butyl Methoxydibenzoylmethane,

[0426] - benzylidene camphor compounds, in particular 3-Benzylidene camphor, 4-Methylbenzylidene camphor, Benzylidene Camphor Sulfonic Acid and Tereph-thalylidene Dicamphor Sulfonic Acid,

[0427] - benzophenone compounds, in particular oxybenzone and n-hexyl 2-(4-diethylamino-2-hydroxybenzoyl)-benzoate,

[0428] - [3,[3-diphenylacrylate] compounds, in particular octocrylene,

[0429] - triazine compounds, in particular Phenylene Bis-Diphenyl triazine, Bis- Ethylhexyloxyphenol Methoxyphenyl Triazine, Ethylhexyl Triazone and Di-thylhexyl Butamido Triazone,

[0430] - benzotriazole compounds, in particular Drometrizole Trisiloxane,

[0431] - benzalmalonate compounds, in particular those cited in US patent 5624663, in especially Polysilicone-15,

[0432] - benzimidazole derivatives, in particular Phenylbenzimidazole Sulfonic Acid,

[0433] - imidazoline compounds, in particular Ethylhexyl Dimethoxybenzylidene Dioxoimidazoline Propionate,

[0434] - bis-benzoazolyl compounds, as described in patents EP 0669323 and US 2463264, in particular Disodium Phenyl Dibenzimidazole Tetra-sulfonate,

[0435] - para-aminobenzoic compounds, in particular PABA, Ethylhexyl Dimethyl PABA and PEG-25 PABA,

[0436] - the compounds methylene bis-(hydroxyphenyl benzotriazole), as described in US applications 5237071, US 5166355, GB 2303549, DE 19726184 and EP 0893119, in particular Methylene bis-Benzotriazolyl Tetramethylbutylphenol,

[0437] - benzoxazole compounds, as described in the EP patent applications 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)-imin ol,3,5-triazine,

[0438] - filter polymers and filter silicones, such as those described in particular in the Request WO 93 / 04665,

[0439] - α-alkylstyrene-derived dimers, such as those described in the application patent DE 19855649,

[0440] - 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,

[0441] - their mixtures.

[0442] Inorganic UV filters are generally mineral UV filters, in particular selected from metal oxides.

[0443] The metal oxides may be selected in particular from titanium, zinc, iron, zirconium, cerium oxides, and mixtures thereof.

[0444] Metal oxide particles may be coated or uncoated.

[0445] The coated particles are more particularly titanium oxides coated with silica, silica and iron oxide, silica and alumina, alumina, alumina and aluminum stearate, silica, alumina and alginic acid, alumina and aluminum laurate, iron oxide and iron stearate, zinc oxide and zinc stearate, silica and alumina treated with silicone, silica, alumina, aluminum stearate treated with silicone, silica treated with silicone, alumina treated with silicone, triethanolamine, stearic acid, sodium hexametaphosphate, or TiO2 treated with octyl trimethylsilane, TiO2 treated with a polydimethylsiloxane, TiO2 anatase / rutile treated with polydimethylhydrogen siloxane, TiO2 coated with triethylhexanoin, aluminium stearate and alumina, TiO2 coated with aluminium stearate, alumina and silicone, TiO2 coated with lauroyl lysine,or TiO2 coated with C945 fluoroalcohol phosphate and aluminum hydroxide.

[0446] Metal oxides may optionally be doped.

[0447] In this respect, we can cite TiO2 particles doped with at least one transition metal such as iron, zinc, manganese, and more particularly manganese.

[0448] 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.

[0449] 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

[0450] According to a particular embodiment, a composition according to the invention comprises 2) at least one coloring material.

[0451] Generally speaking, a "colouring material" 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 in a colour such as yellow, orange, red, violet, blue or green.

[0452] Preferably, a composition according to the invention comprises at least one pigment.

[0453] By "pigments" we mean white or colored, mineral particles or organic, insoluble in liquid hydrophilic and lipophilic phases, intended to color and / or opacify the composition containing them, and different from the composite materials according to the invention. More particularly, the pigments are slightly or not at all soluble in hydroalcoholic media.

[0454] The pigments that can be used are in particular chosen from among the organic and / or mineral pigments known in the art, in particular 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 etibid, "Pigments, Inorganic, 1. General" 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 10.1002 / 14356007.a20_243.pub3).

[0455] These pigments may be in the form of a powder or pigment paste. They may be coated or uncoated.

[0456] 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.

[0457] The pigment may be a mineral pigment. By mineral pigment, we mean 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 dioxide.

[0458] The pigment may be an organic pigment.

[0459] By organic pigment, we mean any pigment that meets the definition in the Ullmann encyclopedia in the chapter on organic pigment.

[0460] The organic pigment may in particular be selected from nitroso, nitro, azo, xanthene, quinoline, anthraquinone, phthalocyanine, metal complex type compounds, isoindolinone, isoindoline, quinacridone, perinone, perylene, diketopyrrolopyrrole, thioindigo, dioxazine, triphenylmethane, quinophthalone.

[0461] Preferably the pigment(s) suitable for the invention are chosen from carbon black, iron oxides in particular red, brown or black, micas coated with iron oxide, triarylmethane pigments in particular blue and violet, such as BLUE 1 LAKE, azo pigments in particular red, such as D&C RED 7, alkali metal salts of lithol red, such as the calcium salt of lithol red B, more preferably the pigment(s) used are chosen from red iron oxides and azo pigments in particular red, such as D&C RED 7.

[0462] The coloring matter(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.

[0463] According to a particular embodiment of the invention, the quantity of pigments varies from 0.5% up to 40%, and preferably from 1 to 20% relative to the weight of the composition of the invention comprising them. 3) Cosmetic active ingredient

[0464] 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.

[0465] In particular, the cosmetic active may be at least one hydrophilic active and / or one lipophilic active, preferably hydrophilic.

[0466] The term “hydrophilic active” means a water-soluble or water-dispersible active capable of forming hydrogen bonds.

[0467] 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-pollution 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, agents that stimulate fibroblast proliferation, agents that stimulate keratinocyte proliferation, muscle relaxants, cooling agents, tightening agents, depigmenting agents, pro-pigmenting agents, keratolytic agents, slimming agents, and agents that act on the energy metabolism of cells.insect repellents, substance P or CRGP antagonists, anti-hair loss agents, and mixtures thereof,

[0468] The active ingredient(s) may in particular be chosen from:

[0469] - vitamins and their derivatives, in particular their esters, such as niacinamide (3-pyridinecarboxamide) nicotinamide (vitamin B3), tocopherol (vitamin E) and its esters (such as tocopheryl acetate), ascorbic acid and its derivatives (vitamin C), retinol (vitamin A),

[0470] - humectants or moisturizers such as urea, hydroxyureas, glycerol, poly- glycerols, glycerolglucoside, diglycerolglucoside, polyglycerylglucosides, xylitylglucoside and plant extracts (in particular tea, mint, orchid, soy, aloe vera, honey, and in particular glycerol;

[0471] - C-glycoside compounds, and preferably hydroxypropyl tetrahydropyrantiol (INCI name) (or proxylane);

[0472] - antioxidant compounds;

[0473] - anti-aging active ingredients, such as hyaluronic acid compounds, and in particular the sodium hyaluronate, salicylic acid compounds and in particular n-octanoyl-5-salycilic acid (capryloyl salicylic acid), adenosine, and the sodium salt of 3-hydroxy-2-pentylcyclopentyl)acetic acid;

[0474] - keratolytic agents such as lactic acid or glycolic acid; and

[0475] - their mixtures.

[0476] Such active ingredients 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

[0477] According to a particular embodiment, a composition according to the invention comprises 4) at least one surfactant.

[0478] Surfactants may be selected from nonionic, anionic, cationic, amphoteric 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.

[0479] Examples of amphoteric surfactants suitable for the invention are in particular chosen from betaines, preferably chosen from alkyl betaines, in particular lauryl betaine; N-alkylamido betaines and their derivatives, in particular co-camidopropylbetaine, lauramidopropylbetaine and N-carboxyethoxyethyl N-cocoylamidoethyl aminoacetate N-disodium; sultaines, in particular cocoyl amidopropylhydroxy sultaine; and mixtures thereof.

[0480] 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.

[0481] The anionic surfactants may be chosen from alkyl ether sulfates, carboxylates, amino acid derivatives, sulfonates, isethionates, taurates, sulfosuccinates, alkylsulfoacetates, phosphates and alkylphosphates, polypeptides, metal salts of Cio-C3o fatty acids, in particular C16-C25, in particular metal stearates and behenates and mixtures thereof.

[0482] Cationic surfactants may be selected from alkylimidazolidiniums, such as isostearyl ethylimidonium ethosulfate, ammonium salts, such as (alkyl Ci2-3o)-tri(alkyl Ci ^ammonium halides like N,N,N-trimethyl-l-docosanaminium chloride (or Behentrimonium chloride).

[0483] Silicone surfactants can be chosen from dimethicone copolyols or silicone elastomers.

[0484] A composition according to the invention may comprise between 0.01% and 2.0% by weight of surfactant, preferably between 0.05% and 1.5% by weight, more preferably between 0.1% and 1.0% by weight, relative to the total weight of the composition. 5) Thickener

[0485] 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.

[0486] Thickeners may be synthetic, natural or of natural origin, preferably natural or of natural origin.

[0487] Such thickeners may in particular be chosen from natural or naturally derived polymers, in particular of vegetable origin.

[0488] These gelling agents are preferably hydrophilic, that is to say soluble or dispersible in water.

[0489] Advantageously, 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, the agars, glycosaminoglucans, gum arabic, sclerotium gum, tragacanth gums, ghatti gums, karaya gums, carob gums, konjac gum, galacto-mannans 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, polymers and copolymers of 2-acrylamido-2-methylpropane sulfonic acid, possibly crosslinked and / or neutralized, water-soluble or water-dispersible silicone derivatives, such as acrylic silicones, polyether silicones and cationic silicones, and mixtures thereof.

[0490] 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. Adjuvants

[0491] A composition according to the invention may further comprise at least one adjuvant commonly used in the chosen cosmetic field: 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.

[0492] 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.

[0493] Of course, a person skilled in the art will take care to choose this or these possible complementary compounds, and / or their quantity, in such a way that the advantageous properties of the particles according to the invention are not, or substantially not, altered by the envisaged addition.

[0494] As stated previously, a composition according to the invention may be cosmetic, and preferably is cosmetic.

[0495] 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.

[0496] 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, i.e. tingling, pulling, which may deter the user from applying this composition. Galenic forms of the compositions

[0497] The compositions, in particular cosmetic compositions, containing the particles according to the invention can be prepared according to techniques well known to those skilled in the art.

[0498] 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.

[0499] The cosmetic compositions may be in the form of an aqueous or hydroalcoholic gel.

[0500] They can be presented in the form of an emulsion, simple or complex (O / W, W / O, O / W / O or W / O / W), such as a cream, a milk, or a cream gel.

[0501] They can also be in anhydrous form, for example in the form of an oil.

[0502] The term “anhydrous composition” means a composition containing less than 5% by weight of water, or even less than 2% water, better still less than 1% water and in particular free of water, the water not being added during the preparation of the composition but corresponding to the residual water provided by the mixed ingredients.

[0503] The cosmetic compositions can for example be used as a makeup product.

[0504] 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.

[0505] 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).

[0506] The composition can be applied by hand or using an applicator.

[0507] In particular, the cosmetic compositions have an SPF value of greater than 5 and preferably greater than 10.

[0508] For the purposes of this invention, "SPF" (Sun Protection Factor) means the sun protection factor that measures the level of protection against UV radiation. The SPF value corresponds to the ratio between the minimum time required to obtain a sunburn (erythematous) with a sunscreen composition and the minimum time required to obtain said sunburn without a sunscreen composition. More specifically, the term "SPF" is defined in the article "A new substrate to measure sunscreen protection factor across the ultraviolet spectrum," J. Soc. Cosmet. Chem., 40, 127-133 (May / June 1989).

[0509] SPF (Sun Protection Factor) assessment can be performed in vitro with a Labsphere® spectrophotometer. The plate is the material on which the sunscreen composition is applied. For this protocol, poly(methyl methacrylate) (PMMA) plates have proven ideal.

[0510] The evaluation of the Sun Protection Factor (SPF) of the compositions can also be carried out in vivo according to the ISO 24444 protocol “Cosmetics - Sun protection test methods - In vivo determination of the sun protection factor (SPF) (2010)”.

[0511] By "UVAPF," we mean the index characterizing protection against UVA radiation. In particular, this index has been measured in vivo using the PPD (Persistent Pigment Darkening) method: PPD measures the skin color observed 2 to 4 hours after UVA exposure. This method has been adopted since 1996 by the Japan Cosmetic Industry Association (JCIA) as the official testing procedure for UVA labeling of products and is frequently used by testing laboratories in Europe and the United States (Japan Cosmetic Industry Association Technical Bulletin. Measurement Standards for UVA Protection Efficacy issued on November 21, 1995, and in effect since January 1, 1996). UVA protection can also be assessed in vitro with the Labsphere® spectrophotometer. The plate is the material to which the sunscreen composition is applied.For this protocol, polymethyl methacrylate (PMMA) sheets proved ideal. ISO 24443 describes such an in vitro method. Cosmetic processes and uses.

[0512] The present invention also relates to the non-therapeutic cosmetic use of composite materials comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one inorganic compound as defined above, for filtering UV radiation, preferably UV-B, comprising at least the application to keratin materials of a composition comprising at least said composite material.

[0513] The present invention also 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 comprising at least a) a bismuth oxycarbonate particle of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one inorganic compound as defined above.

[0514] According to yet another aspect, the present invention also relates to the non-therapeutic cosmetic use of a cosmetic composition comprising at least one composite material including at least a) at least one bismuth oxycarbonate particle of formula (I) (BiO)2 X(CO3), and its solvates, such as its hydrates, wherein -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one inorganic compound such as defined above, to prevent the appearance on the skin, particularly on the face, décolletage, arms, hands and / or shoulders, of darker and / or more colored spots giving the skin a heterogeneity of color.

[0515] 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 comprising at least a) a bismuth oxycarbonate particle of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one inorganic compound as defined above.

[0516] The present invention further relates to the non-therapeutic cosmetic use of a cosmetic composition comprising at least one composite material comprising at least a) a bismuth oxycarbonate particle of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one inorganic compound as defined above, to prevent premature aging of the skin, in particular of the skin of the face, décolleté, arms, hands and / or shoulders.

[0517] It also relates to a non-therapeutic cosmetic process for preventing and / or treating the signs of aging of a keratinous material comprising the application on the surface of the keratinous material of at least one cosmetic composition comprising at least one composite material comprising at least a) a bismuth oxycarbonate particle of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one inorganic compound as defined above.

[0518] According to one aspect of it, the present invention relates to composite materials comprising at least a) a bismuth oxycarbonate particle of formula (I) (BiO) 2 X(CO3), and its solvates, such as its hydrates, wherein -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm and b) at least one inorganic compound as defined above, for their use as agents for filtering UV radiation, in particular UV-B.

[0519] 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.

[0520] 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 those skilled in the art.

[0521] 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

[0522] Example 1: Preparation of bismuth oxycarbonate particles according to the invention

[0523] A solution of bismuth nitrate pentahydrate Bi(NO3)3-5H2O (0.40 M) and D-mannitol (0.87 M) is prepared in 800 mL of water and stirred until the reactants are completely dissolved. 160 mL of an ammonium carbonate solution (2.1 equivalents with respect to bismuth) is then added. A white solid precipitates. This mixture is then transferred to a Teflon autoclave-type reactor and heated for 7.5 hours at 125 °C. The product is isolated by centrifugation and washed 3 times with water before being oven-dried at 60 °C.

[0524] The morphology of bismuth oxycarbonate 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 in ambient air.

[0525] The observation is carried out with a Hitachi HT 7700 transmission electron microscope at an accelerating voltage of 100kV. The average dimensions are obtained via particle size measurement by image analysis using ImageJ software (CA Schneider, WS Rasband, KW Eliceiri, NIH Image to Image: 25 years of image analysis, Nat. Methods. 9 (2012) 671-675).

[0526] The synthesized bismuth oxycarbonate particles are platelets of the following average dimensions:

[0527] Average length L: 86 nm

[0528] Average width 1: 53 nm

[0529] Average thickness e: 28 nm

[0530] Example 2: Syntheses of composite materials according to the invention

[0531] Example 2.A: Synthesis of composite materials A bismuth oxycarbonate-silica from sodium silicate precipitated at pH 6.5

[0532] The bismuth oxycarbonate particles according to Example 1 (2 g) are stirred in 40 mL of distilled water. While stirring, the temperature of the medium is brought to 80°C. At this temperature, 6.64 mL (0.25 equivalent) of an aqueous solution of sodium silicate prepared from a 26.9% solution are added dropwise. mass and diluted by a factor of 10. During the addition, the pH is maintained at 6.5 with dilute sulfuric acid H2SO4 (0.2 M). Stirring and heating are maintained for 5 h, then the reaction medium is left to cool to room temperature.

[0533] After cooling, the composite material A is isolated by centrifugation, washed twice with water and then left to dry in an oven at 60°C, under vacuum (pressure less than 100 mbar).

[0534] Composite material A is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0535] Example 2.B: Synthesis of B bismuth-silica oxycarbonate composite materials from sodium silicate precipitated at pH 10.5

[0536] The bismuth oxycarbonate particles according to Example 1 (2 g) are stirred in 40 mL of distilled water. While stirring, the temperature of the medium is brought to 80 °C. At this temperature, 6.64 mL (0.25 equivalent) of an aqueous solution of sodium silicate prepared from a 26.9% mass solution and diluted by a factor of 10 are added dropwise. During the addition, the pH is maintained at 10.5 with dilute sulfuric acid H2SO4 (0.2 M). Stirring and heating are continued for 5 h, then the reaction medium is allowed to cool to room temperature.

[0537] After cooling, the composite material B is isolated by centrifugation, washed twice with water and then left to dry in an oven at 60°C, under vacuum (pressure less than 100 mbar).

[0538] The composite material B is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0539] Example 2.C: Synthesis of bismuth-silica oxycarbonate composite materials from tetraethylorthosilicate

[0540] Bismuth oxycarbonate particles according to Example 1 (500 mg) are stirred in 10 mL of ethanol and 1 mL of aqueous ammonia. 109 µL of tetraethyl orthosilicate (0.25 equivalent) is added dropwise while stirring. The reaction mixture is kept under stirring and heated to 60 °C for 2 hours.

[0541] The composite material C is isolated by centrifugation, washed twice with ethanol and then dried in an oven at 60 °C, under vacuum (pressure less than 100 mbar).

[0542] The composite material C is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0543] Example 2.D: Synthesis of D bismuth-silica oxycarbonate composite materials from sodium silicate precipitated at pH 6.5

[0544] The bismuth oxycarbonate particles according to Example 1 (2 g) are stirred in 40 mL of distilled water. During stirring, the temperature of the medium is raised at 80 °C. At this temperature, 3.32 mL (0.125 equivalent) of an aqueous sodium silicate solution prepared from a 26.9 wt% solution and diluted by a factor of 10 is added dropwise. During the addition, the pH is maintained at 6.5 with dilute sulfuric acid (H₂SO₄) (0.2 M). Stirring and heating are maintained for 5 h, then the reaction mixture is allowed to cool to room temperature.

[0545] After cooling, the composite material D is isolated by centrifugation, washed twice with water and then left to dry in an oven at 60°C, under vacuum (pressure less than 100 mbar).

[0546] The composite material D is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0547] Example 2.E: Synthesis of bismuth-silica oxycarbonate composite materials from tetraethylorthosilicate

[0548] The bismuth oxycarbonate particles according to Example 1 (500 mg) are stirred in 10 mL of ethanol and 1 mL of aqueous ammonia. 54 μL of tetraethylorthosilicate (0.125 equivalent) are added dropwise, with stirring. The reaction medium is kept stirring and heated to 60°C for 2 hours.

[0549] The composite material E is isolated by centrifugation, washed twice with ethanol and then dried in an oven at 60 °C, under vacuum (pressure less than 100 mbar).

[0550] The composite material E is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0551] Example 2.F: Synthesis of F bismuth-silica oxycarbonate composite materials from sodium silicate precipitated at pH 6.5

[0552] Bismuth oxycarbonate particles according to Example 1 (2 g) are stirred in 40 mL of distilled water. While stirring, the temperature of the medium is raised to 80 °C. At this temperature, 13.3 mL (0.5 equivalent) of an aqueous sodium silicate solution prepared from a 26.9 wt. solution and diluted by a factor of 10 is added dropwise. During the addition, the pH is maintained at 6.5 with dilute sulfuric acid (H2SO4) (0.2 M). Stirring and heating are maintained for 5 h, and then the reaction medium is allowed to cool to room temperature.

[0553] After cooling, the composite material F is isolated by centrifugation, washed twice with water and then left to dry in an oven at 60°C, under vacuum (pressure less than 100 mbar).

[0554] The composite material F is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0555] Example 2.G: Synthesis of composite materials G bismuth oxycarbonate - silica from tetraethylorthosilicate

[0556] The bismuth oxycarbonate particles according to Example 1 (500 mg) are stirred in 10 mL of ethanol and 1 mL of aqueous ammonia. 217 μL of tetraethylorthosilicate (0.5 equivalent) are added dropwise, with stirring. The reaction medium is kept stirring and heated to 60°C for 2 hours.

[0557] The composite material G is isolated by centrifugation, washed twice with ethanol and then dried in an oven at 60°C, under vacuum (pressure less than 100 mbar).

[0558] Composite material G is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0559] Example 2.H: Synthesis of H bismuth oxycarbonate-silica composite materials from sodium silicate precipitated at pH 6.5

[0560] Bismuth oxycarbonate particles according to Example 1 (2 g) are stirred in 40 mL of distilled water. While stirring, the temperature of the medium is raised to 80 °C. At this temperature, 26.6 mL (1 equivalent) of an aqueous sodium silicate solution prepared from a 26.9 wt. solution and diluted by a factor of 10 is added dropwise. During the addition, the pH is maintained at 6.5 with dilute sulfuric acid (0.2 M H₂SO₄). Stirring and heating are maintained for 5 h, and then the reaction medium is allowed to cool to room temperature.

[0561] After cooling, the composite material H is isolated by centrifugation, washed twice with water and then dried in an oven at 60 °C, under vacuum (pressure less than 100 mbar).

[0562] The composite material H is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0563] Example 2.1: Synthesis of bismuth oxycarbonate-titanium dioxide composite materials from titanium tetraisopropoxide

[0564] Bismuth oxycarbonate particles according to Example 1 (2 g) are stirred in 30 mL of 2-propanol. 500 µL of an aqueous sodium hydroxide solution (5 x 10⁴ mol·L⁻¹*) is then added dropwise while stirring. A solution of 581 µL (0.25 equivalent) of titanium tetraisopropoxide diluted in 10 mL of 2-propanol is then added dropwise to the mixture while stirring. The reaction mixture is kept under stirring for 1 hour.

[0565] The composite material I is isolated by centrifugation, washed twice with ethanol and then dried in an oven at 60 °C, under vacuum (pressure less than 100 mbar).

[0566] The composite material I is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0567] Example 2. J: Synthesis of composite materials J bismuth oxycarbonate - silica - titanium dioxide from sodium silicate precipitated at pH 6.5 then titanium tetraisopropoxide

[0568] The bismuth oxycarbonate particles according to Example 1 (2 g) are stirred in 40 mL of distilled water. While stirring, the temperature of the medium is brought to 80 °C. At this temperature, 13.3 mL (0.5 equivalent) of an aqueous solution of sodium silicate prepared from a 26.9% mass solution and diluted by a factor of 10 are added dropwise. During the addition, the pH is maintained at 6.5 with dilute sulfuric acid H2SO4 (0.2 M). Stirring and heating are continued for 5 h, then the reaction medium is allowed to cool to room temperature.

[0569] After cooling, the intermediate composite is isolated by centrifugation, washed twice with water and then dried in an oven at 60 °C, under vacuum (pressure less than 100 mbar).

[0570] 1.86 g of particles of this intermediate composite are stirred in 30 mL of 2-propanol is added dropwise, while stirring, to 500 µL of an aqueous sodium hydroxide solution (5 x 10⁴ mol·L⁻¹). A solution of 563 µL of titanium tetraisopropoxide diluted in 10 mL of 2-propanol is then added dropwise to the mixture while stirring. The reaction mixture is kept under stirring for 1 hour.

[0571] The composite material J is isolated by centrifugation, washed three times with ethanol and then dried in an oven at 60 °C, under vacuum (pressure less than 100 mbar).

[0572] The composite material J is obtained in the form of a white powder and is characterized by UV / Vis spectrophotometry.

[0573] Example 2.K: Synthesis of non-conforming bismuth oxycarbonate-silica composite materials Y from sodium silicate precipitated at pH 6.5

[0574] Bismuth oxycarbonate particles not according to the invention (Alfa Aesar trade reference: platelet particles of (BiO)2CO3, 500 nm in diameter and 50 nm thick) (2 g) are stirred in 40 mL of distilled water. While stirring, the temperature of the medium is raised to 80 °C. At this temperature, 6.64 mL (0.25 equivalent) of an aqueous sodium silicate solution prepared from a 26.9 wt. solution and diluted by a factor of 10 is added dropwise. During the addition, the pH is maintained at 6.5 with dilute sulfuric acid (H2SO4) (0.2 M). Stirring and heating are maintained for 5 h, and then the reaction medium is allowed to cool to room temperature.

[0575] After cooling, the composite material Y is isolated by centrifugation, washed twice with water and then left to dry in an oven at 60°C, under vacuum (pressure less than 100 mbar).

[0576] The composite material Y is obtained in the form of an off-white powder and is characterized by UV / Vis spectrophotometry.

[0577] Example 2.L: Synthesis of Z bismuth oxycarbonate composite materials - silica not in accordance with the invention derived from tetraethylorthosilicate

[0578] Bismuth oxycarbonate particles not in accordance with the invention (Alfa Aesar commercial reference: platelet particles of (BiO)2CO3, 500 nm in diameter and 50 nm thick) (500 mg) are stirred in 10 mL of ethanol and 1 mL of aqueous ammonia. 109 μL of tetraethylorthosilicate (0.25 equivalent) are added dropwise, with stirring. The reaction medium is kept stirring and heated to 60°C for 2 hours.

[0579] The composite material Z is isolated by centrifugation, washed twice with ethanol and then dried in an oven at 60 °C, under vacuum (pressure less than 100 mbar).

[0580] The Z composite material is obtained in the form of an off-white powder and is characterized by UV / Vis spectrophotometry.

[0581] Example 2.M: Summary and dimensions of materials A to J, Y and Z

[0582] The average sizes of the largest dimensions of the heart and bark were determined by direct observation using transmission electron microscopy.

[0583] 1 to 5 milligrams of dry particles are dispersed in 1 mL of absolute ethanol and treated in an ultrasonic bath for two minutes. 5 pL of dispersion are then placed on an observation grid (copper with a surface layer of carbon) and dried in ambient air.

[0584] 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 the measurement of particle dimensions by image analysis using ImageJ software (CA Schneider, WS Rasband, KW Eliceiri, NIH Image to Image J: 25 years of image analysis, Nat. Methods. 9 (2012) 671-675).

[0585] The dimensions of the particles used to form the composite materials are grouped in the following Table 1.

[0586] [Tables 1] Product Average size of largest dimension Compound(s) pH addition (BiO)2xCO3 [(M)POXOH)J 9(H2O)„ A 80 nm 4 ± 2 nm Sodium silicate 6.5 B 80 nm 4 ± 2 nm Sodium silicate 10.5 C 80 nm / TEOS / D 80 nm 5 + 3 nm Sodium silicate 6.5 E 80 nm / TEOS / F 80 nm 10 ± 3 nm Sodium silicate 6.5 G 80 nm / TEOS / H 80 nm 10 ± 4 nm Sodium silicate 6.5 I 80 nm / Titanium tetraisopropoxide / J 80 nm / 1 / Sodium silicate 2 / Titanium tetraisopropoxide 6.5 Y Non-compliant (500 nm) / Sodium silicate 6.5 Z Non-compliant (500 nm) / TEOS /

[0587] Example 3: Absorbance spectra of bismuth oxycarbonate composite materials according to the invention

[0588] UV-visible spectrophotometric absorbance spectra of composite materials prepared according to example 2 were obtained.

[0589] They were obtained by UV-visible spectrophotometry on dispersions at 0.005% by mass of composite material in water for composite materials A to H, J, Y and Z and in a water / propylene glycol / polysorbate 20 mixture (Tween 20, marketed by the company Acros Organics) of respective mass fractions 49.85 / 49.85 / 0.30 for composite material I.

[0590] The quartz cell used for absorbance measurements is 1 cm on each side. The spectrophotometer used is the Genesys 10S from Thermo Fischer Scientific.

[0591] Preparation of dispersions

[0592] The dispersion of composite materials of bismuth oxycarbonate and inorganic oxide, at 0.10% by mass in water for composite materials A to H, J, Y and Z, or in a water / propylene glycol / polysorbate 20 mixture of respective mass fractions 49.85 / 49.85 / 0.30 for composite material I, is exposed to ultrasound for 2 minutes and then stirred with a magnetic stirrer for 16 hours. It is then diluted to 0.005% by mass in bismuth oxycarbonate in the same solvent or mixture of solvents and stirred again for 20 minutes. The absorbance measurement is then carried out.

[0593] The spectra of materials according to the invention (A to J) are compared to bismuth oxycarbonate-silica particles not according to the invention (materials Y and Z) prepared from a commercial reference of bismuth oxycarbonate (BiO) 2CO3 obtained from Alfa Aesar (platelet particles of about 500 nm in diameter by 50 nm in thickness).

[0594] Beyond a predetermined threshold value for measuring UV absorbance, the filtration of UV radiation 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 0.25 are considered effective for the filtration of UV radiation.

[0595] The absorbance spectra are shown in Figures 1 to 12.

[0596] The results are grouped in the following Table 2.

[0597] [Tables2] Absorbance Composite A Composite B Composite C Composite D Composite E Composite F Absorbance at 220 nm 0.61 0.44 0.54 0.52 0.42 0.44 Absorbance at 300 nm 0.72 0.54 0.62 0.62 0.48 0.50 Absorbance at 400 nm 0.34 0.36 0.44 0.36 0.28 0.28 Absorbance at 620 nm 0.12 0.16 0.18 0.14 0.10 0.12 Absorbance Composite G Composite H Composite I Composite J Composite Y (not part of this invention) Composite Z (not part of this invention) Absorbance at 220 nm 0.40 0.54 0.60 0.42 0.11 0.08 Absorbance at 300 nm 0.44 0.56 0.66 0.50 0.10 0.10 Absorbance at 400 nm 0.34 0.28 0.36 0.34 0.10 0.09 Absorbance at 620 nm 0.18 0.10 0.16 0.16 0.08 0.08

[0598] The composite materials according to the invention show good UV absorption and consequently effective filtration of UV rays, particularly in the UV-B range. In contrast, the comparative composite materials Y and Z show low absorbance and do not sufficiently filter the entire UV range.

[0599] Absorbance spectra also show that composite materials according to the invention have high transparency in the visible range between 400 and 780 nm.

Claims

1. Claims Use of a composite material comprising: a. at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 XCO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm; and b. at least one inorganic compound chosen from oxides and / or hydroxides of formula [(M^ OZ(OH),]? (H2O)W; in which: - y is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably y is less than 10, more preferably less than 5, and even more preferably y denotes 1 or 2 or 3; - z is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably z is less than 10, more preferably less than 5; - t is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably t is less than 10, more preferably t is less than 5; - M is a metal, an alkaline earth metal or a metalloid, preferably chosen from silicon Si, titanium Ti, iron Fe, zinc Zn, niobium Nb, tantalum Ta, cerium Ce, manganese Mn, bismuth Bi, tungsten W, aluminum Al, copper Cu and indium In, preferably M denotes Si or Al; - v denotes the oxidation state of M and is a number between 1 and 8, preferably v is less than or equal to 6, and more preferably less than or equal to 4; - w is an integer or fractional number ranging from 0 to 20; - p is an integer ranging from 1 to 5, preferably p is less than or equal to 3, more preferably less than or equal to 2, even more preferably equal to 1; - q is an integer ranging from 1 to 5, preferably q is less than or equal to 2, more preferably q is equal to 1; and - for each inorganic compound: vi= (2z + 0 ± °'5 ' for the filtration of UV-A rays, and / or UV-B rays, preferably UV-B rays, particularly for protecting keratin materials, in particular human materials such as skin, and / or keratin fibers, in particular human materials such as hair; provided that when b) is TiO2, then the composite material is in the form of “core / shell” or “core / shell” preferably, the average size of the largest particle dimension of said composite material is less than or equal to 450 nm.

2. Use according to the preceding claim in which said composite material comprises: Either i): - a core comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2XCO3), as well as its solvates, such as its hydrates, according to the preceding claim; and - a bark comprising at least b) at least one inorganic compound chosen from oxides and / or hydroxides of formula [(M^ OZ(OH),]? (H2O)W formula [(M^)p OZ(OH),]? (H2O)w in which M(v)y, p, z, t, q, and w according to the preceding claim; Either ii): - a core comprising at least b) at least one inorganic compound chosen from the oxides and / or hydroxides of formula [(M^ OZ(OH),]? (H2O)W formula [(M^)p OZ(OH),]? (H2O)w in which M(v)y, p, z, t, q, and w according to the preceding claim; - a bark comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2XCO3), as well as its solvates, such as its hydrates, such as the hydrates according to the preceding claim; - preferably, it being understood that the average size of the largest particle dimension of composite material is in- less than or equal to 450 nm; and more preferably, said composite material comprises: - a core comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2XCO3), as well as its solvates, such as its hydrates, according to the preceding claim; and - a shell comprising at least b) at least one inorganic compound chosen from the oxides and / or hydroxides of formula [(M^ OZ(OH),]? (H2O)W formula [(M^)p OZ(OH),]? (H2O)W in which M(v)y, p, z, t, q, and w according to the preceding claim.

3. Use according to any one of the preceding claims, wherein said composite material has an average size of the largest dimension of composite material particle varying from 10 nm to 300 nm, preferably from 25 nm to 250 nm, and more preferably from 40 nm to 200 nm.

4. Use according to any one of the preceding claims, in which 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 from 0.005 to 10, better still from 0.01 to 5, even better still from 0.02 to 2, and even more preferably from 0.05 to 1.

5. Use according to any one of the preceding claims, said bismuth oxycarbonate particles being crystallized.

6. Use according to any one of the preceding claims, said bismuth oxycarbonate particles being of formula (BiO)2(CO3).

7. Use according to any one of the preceding claims, the largest average dimension of said bismuth oxycarbonate particles being less than or equal to 300 nm.

8. Use according to any one of the preceding claims, said bismuth oxycarbonate particles being in the form of tubes, platelets and / or rods, preferably in the form of platelets and / or rods.

9. Use according to any one of the preceding claims, said or said inorganic compound(s) b) being chosen from the hydrated or non-hydrated forms of Al2O3, SiO2, TiO2, Fe2O3, ZnO, Nb2O5, In2O3, CeO2, Bi2O3 and their mixtures, more preferably the hydrated or non-hydrated forms of Al2O3, SiO2, TiO2, Fe2O3, ZnO and their mixtures, and even more preferably the hydrated or non-hydrated forms of Al2O3, SiO2 and their mixtures.

10. Composite material comprising: Let i): - a core comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 / CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm; and - a bark comprising at least b) at least one inorganic compound chosen from oxides and / or hydroxides of formula [(M^ OZ(OH),]? (H2O)W. ; in which: - y is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably y is less than 10, more preferably less than 5, and even more preferably y denotes 1 or 2 or 3; - z is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably z is less than 10, more preferably less than 5; - t is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably t is less than 10, more preferably t is less than 5; - M is a metal, an alkaline earth metal or a metalloid, preferably chosen from silicon Si, titanium Ti, iron Fe, zinc Zn, niobium Nb, tantalum Ta, cerium Ce, manganese Mn, bismuth Bi, tungsten W, aluminum Al, copper Cu and indium In, preferably M denotes Si or Al; - v denotes the oxidation state of M and is a number between 1 and 8, preferably v is less than or equal to 6, and more preferably less than or equal to 4;

11. - w is an integer or fractional number ranging from 0 to 20; - p is an integer ranging from 1 to 5, preferably p is less than or equal to 3, more preferably less than or equal to 2, even more preferably equal to 1; - q is an integer ranging from 1 to 5, preferably q is less than or equal to 2, more preferably q is equal to 1; and - for each inorganic compound: Ep .=iy. (2z +1) ± 0.5 ' Either ii): - a core comprising at least b) at least one inorganic compound chosen from oxides and / or hydroxides of formula [(M^ OZ(OH),]? (H2O)W in which M(v)y, p, z, t, q, and w are as defined above; - a shell comprising at least a) at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 XCO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm; - it being understood that the average size of the largest particle dimension of composite material is less than or equal to 450 nm. A method of preparing a composite material according to any one of the preceding claims, comprising the steps of: i. having a dispersion of bismuth oxycarbonate particles a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension 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; ii. having an aqueous solution of sodium silicate b), in particular in a Si / Bi molar ratio of between 0.001 and 10, preferably of between 0.01 and 2, and even more preferably of between 0.1 and 1; iii. bringing together said dispersion (i) and said solution (ii) to form the composite material; iv. isolating said composite material.

12. A method for preparing a composite material according to any one of claims 1 to 10, comprising the steps of: (1) providing a dispersion of bismuth oxycarbonate particles a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension 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; (1') adding a basic aqueous solution, preferably aqueous ammonia to said dispersion (1); (2) providing a solution of at least one silicon tetraalkoxide b); (3) bringing said dispersion (1') and said solution (2) together to form the composite material; (4) isolating said composite material.

13. A process for preparing a composite material according to any one of claims 1 to 10, comprising the steps of: (a) providing a dispersion of bismuth oxycarbonate particles a) of formula (I) (BiO)2 X(CO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension 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; (a') optionally adding a basic aqueous solution, preferably sodium hydroxide, preferably with a pH ranging from 8 to 13, and more preferably from 9 to 12, to said dispersion (a); (b) having a solution of at least one titanium tetraalkoxide b), optionally in at least one solvent, in particular in a Ti / Bi molar ratio varying from 0.001 to 2, more preferably from 0.01 to 1.5, and more preferably from 0.1 to 1;(c) bringing together said dispersion (a') and said solution (b) to form the composite material; (d) isolating said composite material.;

14. Composition, in particular cosmetic, comprising at least one composite material according to any one of claims 1 to 10.

15. Composition according to the preceding claim comprising at least: i) at least one composite material according to any one of claims 1 to 10; ii) at least one aqueous phase and / or at least one fatty phase; and iii) at least one compound chosen from: 1) UV filters distinct from the composite materials i); 2) coloring matters; 3) cosmetic active ingredients for the care of keratin materials; 4) surfactants; 5) thickeners; and mixtures thereof.

16. Composition according to any one of claims 14 or 15, said composite materials being present in a content ranging from 0.5% to 70% by weight, preferably from 1% to 50% by weight, even better from 2 to 40% by weight, relative to the total weight of the composition.

17. Non-therapeutic cosmetic process for filtering UV radiation, preferably UV-B, comprising at least the application to keratin materials of a composition comprising a composite material comprising: a. at least one particle of bismuth oxycarbonate of formula (I) (BiO)2 XCO3), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, the largest average dimension of said particles being less than 400 nm; and b. at least one inorganic compound chosen from oxides and / or hydroxides of formula [(M^ OZ(OH),]? (H2O)W; in which: - y is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably y is less than 10, more preferably less than 5, and even more preferably y denotes 1 or 2 or 3; - z is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably z is less than 10, more preferably less than 5; - t is an integer greater than or equal to 1 and less than or equal to 100, preferably less than or equal to 50, preferably t is less than 10, more preferably t is less than 5; - M is a metal, an alkaline earth metal or a metalloid, preferably chosen from silicon Si, titanium Ti, iron Fe, zinc Zn, niobium Nb, tantalum Ta, cerium Ce, manganese Mn, bismuth Bi, tungsten W, aluminum Al, copper Cu and indium In, preferably M denotes Si or Al; v denotes the oxidation state of M and is a number between 1 and 8, preferably v is less than or equal to 6, and more preferably less than or equal to 4; w is an integer or fractional number ranging from 0 to 20; p is an integer ranging from 1 to 5, preferably p is less than or equal to 3, more preferably less than or equal to 2, even more preferably equal to 1; q is an integer ranging from 1 to 5, preferably q is less than or equal to 2, more preferably q is equal to 1; And for each inorganic compound: E i=1 yi (2z + t) + 0.5'

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