FR3150106A1 - Use of at least one particle of bismuth oxycarbonate and at least one polymer for the filtration of ultraviolet radiation - Google Patents

Abstract

Use of at least one particle of bismuth oxycarbonate and at least one polymer for filtering ultraviolet radiation The present invention relates to the use of i) one or more particles of bismuth oxycarbonate of empirical formula (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 ii) one or more polymers; the mass ratio R i) / ii) being greater than or equal to 1; for filtering UV rays, in particular UV-A and/or UV-B, in particular UV-B, as well as compositions and methods for therapeutic treatment. Figure for the abstract: None

Description

Use of at least one particle of bismuth oxycarbonate and at least one polymer for the filtration of ultraviolet radiation

The present invention relates to the field of sun protection and more particularly to the use of at least one particle i) of bismuth oxycarbonate, as well as its solvates, such as its hydrates, associated with at least one ii) polymer in a mass ratio R of particle(s) of bismuth oxycarbonate / polymer(s) greater than or equal to 1, for the filtration of ultraviolet radiation, in particular the filtration of UV-B.

The present invention also relates to a cosmetic composition and a process using ingredients i) and ii) to filter UV radiation, in particular UV-B, in particular for the protection of keratin materials, in particular human, in particular the skin and/or keratin fibers, in particular human, such as hair.

Keratin materials are exposed to sunlight on a daily basis.

It is known that light rays with wavelengths between 280 nm and 400 nm allow the tanning of 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.

It is also known that UV-A rays, with wavelengths between 320 and 400 nm, penetrate deeper into the skin than UV-B rays. UV-A rays promote rapid and persistent pigmentation of the skin. Daily exposure to UVA radiation, even for short periods, under normal conditions, can also cause a degradation of collagen and elastin fibers, resulting in a change in the skin microrelief, the appearance of wrinkles and irregular pigmentation (i.e. brown spots, uneven skin tone, etc.).

Additionally, prolonged exposure to the sun can further dry out hair, making it brittle.

Therefore, protection of keratin materials, particularly human ones, such as skin, is essential.

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

Many skin photoprotective cosmetic compositions have been proposed to date. They generally contain organic UV filters and/or inorganic UV filters which act according to their own chemical nature and according to their own physical properties by absorption, reflection or diffusion of UV radiation. They generally contain combinations of oil-soluble organic UV filters and/or water-soluble organic UV filters associated with metal oxide pigments such as titanium dioxide (TiO ₂ ) or zinc oxide (ZnO).

As for the usual organic filters, they must have acceptable cosmetic properties, good solubility in usual solvents, particularly in oils, but also good photostability, 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 formulatory field.

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

_TiO2 and ZnO are the most common mineral UV filters used.

However, one of the major drawbacks of such mineral filters is that, once applied to keratin materials, particularly human skin, such as the skin, they produce a whitening effect on the skin which is cosmetically undesirable and generally not appreciated by users.

This effect is all the more marked as the concentration of mineral filters in the composition is high, which limits their concentration in sun formulations.

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 with 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.

In addition, 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.

Furthermore, the use of mineral filters requires that these filters can be formulated homogeneously in cosmetic compositions so that the protection provided is identical at all times and for all applications. It is therefore necessary to be able to formulate mineral filters without them settling and/or agglomerating within the formulations that implement them so that filtration is homogeneous.

Furthermore, the use of bismuth carbonate nanotubes in the presence of polyvinylpyrrolidone (PVP) combined with oleic acid for tumor-targeted chemotherapy combined with renal investigation in high-contrast computed tomography imaging has been described in the literature ( Nano Lett ., 18, 2, 1196–1204 Xi Hu et al. (2018)).

However, consumers are increasingly looking for effective and stable products that are also easy to apply, provide long-lasting comfort and have satisfactory sensory properties.

There therefore remains a need for sunscreen compositions comprising inorganic UV filters which are effective in photoprotection and which do not have the drawbacks presented above.

In particular, there remains a need for sunscreen compositions comprising inorganic UV filters capable of effectively blocking UV rays, in particular in the UV-B and UV-A range, and in particular UV-B rays, having a high transparency to visible light, which do not whiten keratin materials, in particular human keratin materials, such as skin and/or human keratin fibres, such as hair to which they are applied and having good cosmetic properties.

In particular, there remains a need for stable sunscreen compositions comprising mineral UV filters, distinct from titanium dioxide or zinc oxide, which are equally effective, which are transparent, which do not form agglomerates, which do not sediment, which do not cause sensations of roughness and dryness on the skin, and which are easy to formulate, particularly at high concentrations.

There is also a need for mineral filters capable of effectively blocking UV rays, particularly in the UV-B and/or UV-A range, including UV-B, without any alteration in performance linked to the agglomeration of said mineral filters and/or the deposition of said filters.

The present invention aims precisely to propose new compositions making it possible to meet these expectations.

Thus, according to a first of its aspects, the present invention relates to the use of:

(i) one or more particles of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), as well as its solvates, such as its hydrates, 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

(ii) one or more polymer(s);

the mass ratio R of particle(s) i) / polymer(s) ii) being greater than or equal to 1;

it being understood that:

- when the composition contains polysorbate 20, namely polyoxyethylene sorbitan monolaurate, of formula:

as the only polymer ii), then the mass ratio R of particles i) / polymer(s) ii) is different from 2/0.29; and

- when the composition contains two polymers ii) one of which is polysorbate 20 in a content of 0.3% by mass then the polymer ii) is other than xanthan gum;

for the filtration of UV rays, in particular UV-A and/or UV-B rays, in particular UV-B rays.

Preferably, the largest average dimension of said particles i) is less than or equal to 300 nm.

In particular, the use according to the invention relates to the protection of keratin materials, in particular human materials such as skin and/or keratin fibers, in particular human materials such as hair.

Preferably, the bismuth oxycarbonate particles i) are crystallized.

According to another aspect, the present invention also relates to a non-therapeutic cosmetic process for treating keratin materials, in particular human keratin materials, such as the skin and/or keratin fibers, in particular human keratin fibers, such as hair, comprising at least the application to the keratin materials of i) at least one particle of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), 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 ii) of at least one polymer, and it being understood that the mass ratio R particle(s) i)/polymer(s) ii) is greater than or equal to 1, preferably R is greater than 1.

Preferably, the process of the invention is a non-therapeutic cosmetic process comprising at least the application to keratin materials of a composition according to the invention as defined below.

Another subject of the invention is a preferably cosmetic composition, comprising i) at least one particle of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), 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 ii) at least one polymer, and it being understood that:

- R i) / ii) is greater than or equal to 1, preferably R is greater than 1;

- when ii) the polymer is polyvinylpyrrolidone (PVP) then said composition does not contain oleic acid; and

- when the composition contains polyoxyethylene sorbitan monolaurate as the sole polymer ii), then the mass ratio particles i) / polymer(s) ii) is different from 2/0.29; and

when the composition contains two polymers ii) one of which is polysorbate 20 at a content of 0.3% by mass then polymer ii) is other than xanthan gum.

According to a preferred embodiment, the present invention relates to the use of said particles for the filtration of UV-B radiation.

Preferably, the uses, methods and compositions according to the invention do not use polysorbate 20, namely polyoxyethylene sorbitan monolaurate, of formula:

Surprisingly, and as is apparent from the examples below, the inventors have discovered that the compositions according to the invention exhibit excellent efficiency for the filtration of ultraviolet radiation, and in particular UV-B rays, as well as high transparency in visible radiation, and make it possible to give the composition containing them cosmetic properties that are satisfactory for the consumer.

In particular, the compositions according to the invention make it possible to have a good level of filtration, by limiting the formation of aggregates which would be likely to generate uncomfortable granular textures for the consumer and without generating whitening upon application.

For the purposes of the present invention, the term " high transparency in visible radiation " means compositions or particles having a high transmission of rays between 400 and 780 nm.

For the purposes of the present invention, the term " efficiency for filtering ultraviolet radiation " means compositions or particles having an absorbance threshold in UV, in the dispersion medium comprising said particles or said composition, a particle mass concentration of 0.01%, greater than 0.5, preferably greater than or equal to 1.0, and more preferably still greater than or equal to 1.5. The higher the absorbance threshold, the greater the UV radiation filtration efficiency.

UV-B radiation means the wavelength range from 280 to 320 nm. UV-A radiation means the wavelength range from 320 to 400 nm. Visible light means the wavelength range from 400 to 780 nm.

Thus, for the purposes of the present invention, the term " UV filter " is intended to denote any compound that filters ultraviolet (UV) radiation in the wavelength range from 280 nm to 400 nm. The term " UV-B filter " is intended to denote any compound that filters ultraviolet (UV) radiation in the wavelength range from 280 nm to 320 nm. The term "UV-A filter" is intended to denote any compound that filters ultraviolet (UV) radiation in the wavelength range from 320 nm to 400 nm.

For the purposes of the present invention, the term "fatty substance" means an organic compound which is immiscible in water at ordinary temperature (25°C) and at atmospheric pressure (760 mm Hg) (solubility less than 5%, and preferably 1%, even more preferably 0.1%); in addition, the fatty substances are miscible in particular in all proportions in organic solvents under the same temperature and pressure conditions, such as for example in halogenated solvents such as chloroform, dichloromethane, lower alcohols such as ethanol or aromatic solvents such as benzene or toluene.

By " organic or mineral acid salt " is meant more particularly the salts chosen from a salt derived from i) hydrochloric acid HCl, ii) hydrobromic acid HBr, iii) sulfuric acid H ₂ SO ₄ , iv) alkylsulfonic acids: Alk-S(O) ₂ OH such as methylsulfonic acid and ethylsulfonic acid; v) arylsulfonic acids: Ar-S(O) ₂ OH such as benzenesulfonic acid and toluenesulfonic acid; vi) citric acid; vii) succinic acid; viii) tartaric acid; ix) lactic acid, x) alkoxysulfinic acids: Alk-OS(O)OH such as methoxysulfinic acid and ethoxysulfinic acid; xi) aryloxysulfinic acids such as tolueneoxysulfinic acid and phenoxysulfinic acid; xii) phosphoric acid H ₃ PO ₄ ; xiii) acetic acid CH ₃ C(O)OH ; xiv) triflic acid CF ₃ SO ₃ H and xv) tetrafluoroboric acid HBF ₄ ; as well as salts of so-called "acidic" amino acids such as salts of glutamic acid, aspartic acid;

By "salts of organic or mineral bases " we mean salts of bases or alkaline agents as defined below as alkali metal hydroxides such as soda, potash, ammonia, amines or alkanolamines or salts of so-called "basic" amino acids such as lysine or arginine.

By " cationic counterion " is meant a cation or a cationic group derived from an organic or mineral base salt counterbalancing an anionic charge of at least one ingredient of the composition according to the invention; more particularly the cationic counterion is chosen from i) alkali metals such as sodium, potassium, preferably Na ⁺ , ii) alkaline earth metals such as calcium; iii) ammonium R ₄ N ⁺ with R, identical or different, representing a hydrogen atom, or a (C ₁ -C ₆ )alkyl group optionally substituted by one or more hydroxyl groups, preferably R represents a hydrogen atom or a (C ₁ -C ₄ )alkyl group such as methyl.

The compositions according to the invention are in particular intended to protect keratin materials, in particular the skin and hair, from UV radiation, in particular in cosmetic compositions for the fields of sun protection, care, hair treatment and makeup.

Thus, according to another aspect, 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 keratin materials of a composition according to the invention as defined above.

The invention also relates, according to another of its aspects, to a composition, in particular cosmetic, comprising at least:

(i) particles of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), 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;

(ii) at least one polymer;

iii) optionally at least one solvent; and

iv) optionally at least one compound chosen from: a) UV filters distinct from bismuth oxycarbonate particles i), as well as its solvates, such as its hydrates; b) coloring matters; c) cosmetic active ingredients for the care of keratin materials; d) surfactants distinct from said polymer ii); e) thickeners distinct from said polymer ii); and mixtures thereof;

and it being understood that:

- the mass ratio R i) / ii) is greater than or equal to 1, preferably R is greater than 1;

- when ii) the polymer is polyvinylpyrrolidone (PVP) then said composition does not contain oleic acid; and

- when the composition contains polyoxyethylene sorbitan monolaurate as the sole polymer ii), then the mass ratio particles i) / polymer(s) ii) is different from 2/0.29; and

- when the composition contains two polymers ii) one of which is polysorbate 20 in a content of 0.3% by mass then polymer ii) is other than xanthan gum.

By “ keratin materials ” we mean in particular the skin, including the scalp, the lips, and also keratin fibres such as the hair, eyelashes, eyebrows, in particular the skin and/or the hair, and preferably the skin.

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

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

Other characteristics, variants and advantages of the compositions according to the invention will emerge more clearly upon reading the description and examples which follow.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition A1 according to the invention, and on sodium polymethacrylate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition A2 according to the invention, and on sodium polymethacrylate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition A3 according to the invention, and on sodium polymethacrylate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition B1 according to the invention, and on the methacrylic copolymer, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition B2 according to the invention, and on the methacrylic copolymer, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition B3 according to the invention, and on the methacrylic copolymer, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition C1 according to the invention, and on sodium alginate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition C2 according to the invention, and on sodium alginate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition C3 according to the invention, and on sodium alginate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition D1 according to the invention, and on dextran sulfate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition D2 according to the invention, and on dextran sulfate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition D3 according to the invention, and on dextran sulfate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition E1 according to the invention, and on sodium lignosulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition E2 according to the invention, and on sodium lignosulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition E3 according to the invention, and on sodium lignosulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition F1 according to the invention, and on calcium lignosulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition F2 according to the invention, and on calcium lignosulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition F3 according to the invention, and on calcium lignosulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition H1 according to the invention, and on sodium polystyrene sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the H2 composition according to the invention, and on sodium polystyrene sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition H3 according to the invention, and on sodium polystyrene sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition I1 according to the invention, and on sodium polystyrene sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition I2 according to the invention, and on sodium polystyrene sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition I3 according to the invention, and on sodium polystyrene sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition J1 according to the invention, and on sodium polyanethole sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition J2 according to the invention, and on sodium polyanethole sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition J3 according to the invention, and on sodium polyanethole sulfonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition K1 according to the invention, and on chitosan, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition K2 according to the invention, and on chitosan, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition K3 according to the invention, and on chitosan, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition L according to the invention, and on carrageenan, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition M1 according to the invention, and on the modified phosphonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition M2 according to the invention, and on the modified phosphonate, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition N1 according to the invention, and on polyethyleneimine, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition N2 according to the invention, and on polyethyleneimine, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition N3 according to the invention, and on polyethyleneimine, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition O1 according to the invention, and on the hydrolyzed soy protein, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the O2 composition according to the invention, and on the hydrolyzed soy protein, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition O3 according to the invention, and on the hydrolyzed soy protein, in water.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition P1 according to the invention, and on polyglyceryl-6-polyricinoleate, in caprylic/capric triglyceride.

represents the absorbance spectra obtained by UV-visible spectrophotometry on composition P2 according to the invention, and on polyglyceryl-6-polyricinoleate, in caprylic/capric triglyceride.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition Q1 according to the invention, and on the polyglyceryl-4-diisotearate/polyhydroxystearate/sebacate, in caprylic/capric triglyceride.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition Q2 according to the invention, and on polyglyceryl-4-diisotearate/polyhydroxystearate/sebacate, in caprylic/capric triglyceride.

represents the absorbance spectra obtained by UV-visible spectrophotometry on the composition Q1 according to the invention, and on myristoyl pullulan, in caprylic/capric triglyceride.

Detailed description

As indicated above, the invention relates to a composition, in particular a cosmetic composition, comprising at least i) bismuth oxycarbonate particles of empirical formula (BiO) _{2- x} (CO ₃ ), 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; ii) at least one polymer, and iii) optionally at least one solvent; and it being understood that the mass ratio R i) / ii) is greater than or equal to 1, preferably R is greater than 1; when ii) the polymer is polyvinylpyrrolidone (PVP) then said composition does not contain oleic acid; and when the composition contains polyoxyethylene sorbitan monolaurate as the sole polymer ii), then the mass ratio particles i) / polymer(s) ii) is different from 2/0.29; and when the composition contains two polymers ii) one of which is polysorbate 20 in a content of 0.3% by mass then the polymer ii) is other than xanthan gum.

Bismuth oxycarbonate particles i)

The bismuth oxycarbonate particles according to the invention have the empirical formula (BiO) _{2- x} (CO ₃ ), 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.

Preferably, x is 0 and the empirical formula of the bismuth oxycarbonate particles is (BiO) ₂ ( _CO3 ).

According to a particular embodiment, said particles of bismuth oxycarbonate i), as well as its solvates, such as its hydrates, may be present in the composition according to the invention, preferably cosmetic, in a content ranging from 0.01% to 80% by weight, in particular from 0.05% to 75% by weight, preferably from 0.08% to 60% by weight, relative to the total weight of the composition.

According to a particular embodiment, said particles of bismuth oxycarbonate i), as well as its solvates, such as its hydrates, may be present in the composition according to the invention, preferably cosmetic, in a content ranging from 0.5% to 40% by weight, in particular from 1% to 30% by weight, preferably from 2 to 20% by weight, relative to the total weight of the composition.

According to a particular embodiment, the compositions according to the invention contain at least 0.01% by weight of bismuth oxycarbonate particles i), as well as its solvates, such as its hydrates, relative to the total weight of the composition.

According to a particular embodiment, said particles of bismuth oxycarbonate i), as well as its solvates, such as its hydrates, may be present in the composition according to the invention, preferably cosmetic, in a content ranging from 0.01% to 80% by weight, preferably from 0.08% to 75% by weight, relative to the total weight of the composition.

According to a particular embodiment, said particles of bismuth oxycarbonate i), as well as its solvates, such as its hydrates, may be present in the composition according to the invention, preferably cosmetic, in a content ranging from 30% to 80% by weight, preferably from 35% to 75% by weight, relative to the total weight of the composition.

According to a particular embodiment, said particles of bismuth oxycarbonate i), as well as its solvates, such as its hydrates, may be present in the composition according to the invention, preferably cosmetic, in a content ranging from 1% to 60% by weight, preferably from 2% to 55% by weight, relative to the total weight of the composition.

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

According to one form of the invention, the bismuth oxycarbonate particles are amorphous.

According to a preferred form of the invention, the bismuth oxycarbonate particles are crystallized.

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

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

By " crystallized " as used herein is meant that the atoms constituting the bismuth oxycarbonate particles are arranged in an orderly manner. In other words, the crystallized bismuth oxycarbonate particles are organized materials.

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

Preferably, the crystallized particles required according to the invention have the crystalline phase of the natural ore bismutite, referred to as lamellar, and which has an alternation of [Bi ₂ O ₂ ] ²⁺ and [CO ₃ ] ^2- layers.

Such particles crystallize in an orthorhombic system of space group Imm2 .

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 V _lattice = 0.204 nm ³ . This particular arrangement of atoms allows in particular the growth of anisotropic objects.

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.

Particle size

According to the invention, the largest average dimension of the crystallized or amorphous particles, preferably crystallized, of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6 is less than 400 nm.

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

By " average size " is meant the number-average value of the dimensions of the primary particles. The dimensions of the particles can be determined by transmission electron microscopy, for example using a Hitachi HT 7700 microscope, in particular at an acceleration voltage of 100 kV, by scanning electron microscopy, or from the measurement of the specific surface area by the BET method, or by means of a laser granulometer. Preferably, the dimensions of the particles are determined by transmission electron microscopy, for example using a Hitachi HT 7700 microscope, in particular at an acceleration voltage of 100 kV or by scanning electron microscopy. Preferably, the measurement is made on the smallest individualized or individualizable objects. The mean number value can be calculated by analyzing the obtained images using software, such as Image J software (CA Schneider, WS Rasband, KW Eliceiri, NIH Image to ImageJ: 25 years of image analysis, Nat. Methods. 9 (2012) 671–675).

The average dimension is chosen from the average length L, the average width l, the average thickness e, or the average diameter d.

By " the largest average dimension " of the particles is meant the largest average dimension of a surface, such as a face, that can be measured between two diametrically opposite points of an individual particle. For the purposes of the invention, this dimension is defined as the maximum Feret diameter.

The " length " L of a particle is its largest dimension observable on a picture taken in a direction perpendicular to the plane on which the said particle rests.

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

The " diameter " d of a particle is the largest dimension observable along a line passing through the center of a circle or a sphere.

Particle shape

According to the invention, the bismuth oxycarbonate particles of empirical formula (BiO) _{2- x} (CO ₃ ), as well as its solvates, such as its hydrates, in which -0.4 < x < 0.6, can be in any form.

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

According to one embodiment, the particles i) are of identical morphology.

In particular, when the composition comprises particles i) of identical morphology, the composition of the invention consists of particles in the form of platelets or sheets or rods or spheres or flowers or pompoms or threads or filaments or fibers or needles, or cubes, preferably in the form of platelets or rods.

According to one embodiment, the particles i) are of different morphologies.

In particular, when the composition comprises particles i) of different morphologies, the composition of the invention comprises one or more particles chosen from particles in the form of tubes, platelets, sheets, rods, spheres, flowers, pompoms, threads, filaments, fibers, needles, cubes or any of their mixtures.

The particles according to the invention can further aggregate in the form of superstructures. For example, platelets, tubes and/or rods can aggregate in the form of spheres, flowers or even pompoms.

According to a preferred embodiment, the particles according to the invention are in the form of platelets and/or rods.

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

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 in any proportion of platelets and/or rods and/or tubes, in particular in a mixture in any proportion of platelets and/or rods.

According to a preferred embodiment, the particles used according to the invention are mainly or exclusively in the form of platelets.

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

In particular, when in platelet form, bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, possess:

- 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;

- 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;

- 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

- with e < l < L .

According to one embodiment, the bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, are predominantly or exclusively in the form of rods or comprise particles in the form of rods.

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 to this polygonal base is less than the length L of the prism.

In particular, when in the form of rods, whether cylindrical or prismatic, bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, have:

- 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;

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

- with L > d .

According to one embodiment, the bismuth oxycarbonate particles of the invention, as well as its solvates, such as its hydrates, contain particles in the form of tubes.

A particle in the form of a " tube " has a hollow cylindrical shape and its length L is greater than its diameter d .

In particular, when in the form of tubes, bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, possess:

- 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;

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

- with L > d .

For the purposes of the present invention, the term " predominantly in the form of platelets/rods " means 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 respectively.

Particle doping

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

In particular, bismuth oxycarbonate particles can be doped with one or more chemical elements capable of being inserted into the structure or of partially replacing elements already present.

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

According to a particular embodiment, the doping partly concerns cations in insertion or substitution of bismuth within the limit of 20% of the bismuth composition.

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%.

In particular, the bismuth oxycarbonate particles may be doped with cations derived from elements selected from aluminum (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).

Preferably, the bismuth oxycarbonate particles may 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.

According to an alternative embodiment, the bismuth oxycarbonate particles are doped with cations derived from manganese, and the doping rate varies in particular from 0.5% to 2%.

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

According to another particular embodiment, the doping concerns in part or in total anions in insertion or in substitution of the carbonate group within the limit of 20% of the carbonate composition.

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%.

In particular, the bismuth oxycarbonate particles may be doped with anions derived from elements selected from fluorine (F), sulfur (S), chlorine (Cl), bromine (Br), iodine (I), and/or with polyatomic anions, in particular selected from sulfate ion (SO ₄ ^2- ), sulfonate ion (S(=O) ₂ -O ^- ), sulfite ion (SO ₃ ^2- ), phosphate ion (PO ₄ ^3- ) and/or iodate ion (IO ₃ ^- ).

Preferably, the bismuth oxycarbonate particles may be doped with S ^2- , SO ₃ ^2- , SO ₄ ^2- , Cl ^- and/or I ^- , more preferably with SO ₃ ^2- , SO ₄ ^2- and/or Cl ^- , and more preferably with Cl ^- or SO ₄ ^2- .

According to an alternative embodiment, the bismuth oxycarbonate particles are doped with anions derived from chlorine, and the doping rate varies in particular from 0.01% to 0.1%.

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

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

According to another embodiment, the bismuth oxycarbonate particles are doped with cations preferably from elements chosen from titanium, vanadium, manganese, iron, copper, zinc, lanthanum, and/or cerium, more preferably chosen from manganese, iron and/or cerium, and even more preferably chosen from manganese or iron, and with anions preferably 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 (SO ₄ ^2- ), sulfonate ion (S(=O) ₂ -O ^- ), sulfite ion (SO ₃ ^2- ), phosphate ion (PO ₄ ^3- ) and/or iodate ion (IO ₃ ^- ), more preferentially with S ^2- , SO ₃ ^2- , SO ₄ ^2- , Cl ^- and/or I ^- , even more preferentially with SO ₃ ^2- , SO ₄ ^2- and/or Cl ^- , and particularly preferably with Cl ^- , I ^- or SO ₄ ^2- .

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

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

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

Process for the preparation of particles of ’ bismuth oxycarbonate

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

For example, the synthesis of bismuth oxycarbonate particles is described in the article by Ni et al. (Fabrication, modification and application of (BiO) ₂ CO ₃ -based photocatalysts: A review, Applied Surface Science, 365, 2016, 314–335).

In particular, bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, can be prepared solvothermally, electrochemically, by co-precipitation, or at reflux, and preferably solvothermally or at reflux.

According to a first embodiment variant, the 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 makes it possible to obtain bismuth oxycarbonate particles in the form of platelets and/or rods, the largest dimension of which varies from 50 to 300 nm.

The synthesis of particles by solvothermal means is notably described in the articles of Cheng, G. et al. (Shape-controlled solvothermal synthesis of bismuth subcarbonate nanomaterials, J. Solid State Chem. 183, 1878–1883 (2010)); Ruan, M. M. 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 Bi ₂ O ₃ and (BiO) ₂ CO ₃ 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. (Preparation, electronic structure, and photocatalytic properties of Bi ₂ O ₂ CO ₃ nanosheet, Appl. Surf. Sci., 257, 2010, 172–175); Zheng et al. (Synthetic Bi ₂ O ₂ CO ₃ 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 Bi ₂ O ₂ CO ₃ , 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).

The synthesis of particles by electrochemical route is notably described in the article by Hu, Y. et al. (Simple hydrolysis route to synthesize Bi ₂ O ₂ CO ₃ nanoplate from Bi nanopowder and its photocatalytic application, Materials Letters, 170, 2016, 72–75).

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, Bi ₁₂ O ₁₇ Cl ₂ , α-Bi ₂ O ₃ , and (BiO) ₂ CO ₃ ) by solution-phase methods, J. Solid State Chem., 180, 2007, 2510–2516).

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).

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 solvothermal means, for example according to the method described by Cheng et al. , or at reflux, for example according to the method described by Chen et al..

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.

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

In particular, the bismuth(III) complex(es) is(are) chosen 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.

Bismuth(III) complex(es) can also be obtained from bismuth minerals, such as elemental bismuth and/or bismuth oxide and/or bismuth sulfide.

Preferably, the bismuth(III) complex(es) is(are) bismuth(III) nitrate and its hydrated forms of formula Bi( _NO3 ) ₃ · xH2O , and preferably is bismuth nitrate pentahydrate of formula Bi( _NO3 ) ₃ · _{5H2O .}

In particular, the carbonating agent(s) is (are) selected from Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Rb ₂ CO ₃ , Cs ₂ CO ₃ , (NH ₄ ) ₂ CO ₃ , LiHCO ₃ , NaHCO ₃ , KHCO ₃ , RbHCO ₃ , CsHCO ₃ , (NH ₄ ) HCO ₃ , urea (NH ₂ ) ₂ CO and urea derivatives, CO ₂ , preferably from Na ₂ CO ₃ , K ₂ CO ₃ , (NH ₂ ) ₂ CO, (NH ₄ ) ₂ CO ₃ , and more preferably from (NH ₂ ) ₂ CO and/or (NH ₄ ) ₂ CO ₃ .

Polyols are compounds having several hydroxyl functions. They can 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.

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.

According to a first embodiment variant, the polyol(s) may also be used as a solvent. The bismuth oxycarbonate particles may then be obtained, for example, according to the process described below.

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.

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

In case of doping with one or more cation(s) and/or 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 polyol mixture is not liquid at room temperature, all solids are mixed.

The resulting mixture is then heated to between 90°C 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.

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.

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

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

In the case where the polyol(s) are used as solvents, the particles of bismuth oxycarbonate, as well as its solvates, such as its hydrates, obtained are in the form of platelets, preferably with an average thickness e of between 2 and 15 nm, and/or in the form of tubes.

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.

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.

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

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. The resulting mixture is then heated 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.

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

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

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

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

According to this variant, the synthesis process further uses a solvent distinct from the polyols, or a mixture of solvents distinct from the polyols. In particular, the solvent or the mixture of solvents is chosen from polar solvents, preferably from polar and protic solvents, such as water; C ₁ -C ₆ alcohols such as ethanol or isopropanol; and mixtures thereof, and even more preferably the solvent is water.

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.

Polymer ii)

The compositions according to the invention comprise at least one polymer ii).

The polymer(s) ii) are natural and/or synthetic, hydrophilic and/or hydrophobic and/or amphiphilic, anionic and/or cationic and/or zwitterionic and/or non-ionic.

The polymer(s) ii) may be silicone or non-silicone.

According to a particular embodiment, the polymer(s) ii) are or comprise at least one silicone polymer.

Examples of silicone polymers ii) include dimethicone copolyols, in particular the mixture of cyclomethicone and dimethicone copolyol, sold in particular under the name "DC 5225 C ^® " by the company Dow Corning, and alkyl-dimethicone copolyols, in particular Laurylmethicone copolyol, sold in particular under the name "Dow Corning 5200 Formulation Aid" by the company Dow Corning, Cetyl dimethicone copolyol and the mixture of cetyl dimethicone copolyol, polyglycerol isostearate (4 moles) and hexyl laurate.

According to a preferred embodiment, the polymer(s) ii) do not contain silicon atoms.

According to a preferred embodiment, the mass by weight Mw of the polymers ii) is greater than or equal to 2000.

By " anionic polymer " is meant a polymer containing one or more anionic groups, in particular carboxyls, carboxylates, sulfates, sulfonic acids, sulfonates, phosphates, phosphonic acids, phosphonates, preferably chosen from carboxylates and/or sulfonates. The anionic derivatives can be salified in the form of salts of alkali or alkaline-earth metals, preferably sodium or calcium.

By " cationic polymer " is meant a polymer containing one or more cationic groups, charged regardless of the pH, or cationizable. Preferably, the cationic polymers ii) carry amino groups.

By " nonionic polymer " is meant a polymer which does not carry charged groups or which may be charged by varying the pH.

The polymer(s) ii) are cyclic or acyclic (containing no cycle in their structure).

The cyclic polymer(s) ii) may be aromatic (containing at least one aromatic ring) or non-aromatic.

Examples of cyclic aromatic polymers (ii) include lignosulfonic acid, lignosulfonates, polystyrene sulfonics, polystyrene sulfonates, anionic polyanethol derivatives, in particular polyanethol sulfonates, and mixtures thereof.

Their molar mass is preferably less than 2,000,000, more preferably less than 1,000,000, more particularly between 10,000 and 900,000.

According to a particular embodiment, said polymer(s) ii) are chosen from polystyrene sulfonic acid, polystyrene sulfonate, in particular polystyrene sulfonates of alkali metal or alkaline earth metal salts, in particular sodium or calcium. Preferably, their mass Mw is less than 1,000,000, more preferably less than 900,000, even more preferably less than 500,000, better still less than 250,000, even better still less than 150,000, in particular between 10,000 and 150,000.

According to one embodiment, said polymer(s) ii) are chosen from lignosulfonic acids or their lignosulfonate salts of alkali or alkaline earth metals, in particular sodium or calcium. Preferably, their mass Mw is less than 500,000, more preferably less than 200,000, even more preferably less than 100,000, better still between 2000 and 100,000, even better still between 10,000 and 100,000.

According to one embodiment, said polymer(s) ii) are chosen from anionic polyanethole derivatives, in particular polyanethole sulfonates of alkali or alkaline earth metals, in particular sodium or calcium, in particular sodium. Preferably, their mass Mw is less than 500,000, more preferably less than 200,000, even more preferably less than 100,000, better still less than 50,000, even better still between 2000 and 50,000, even better still between 1000 and 20,000.

Preferably, the non-aromatic cyclic polymers ii) are chosen from polysaccharides, these polysaccharides being able to be anionic, cationic or non-ionic, preferably cationic or anionic.

According to a particular embodiment, the polymer(s) ii) of the invention represent a mixture of polymers ii) one of which is a polysaccharide or one of its salts, its α or β anomers, its optical isomers of L or D configuration and its solvates, such as hydrates.

According to a particular embodiment, the polymer(s) ii) of the invention represent a single polysaccharide or one of its salts, its α or β anomers, its optical isomers of L or D configuration and their solvates, such as hydrates.

In particular, the polymers ii) cyclic non-aromatic non-ionic polysaccharides are chosen from alkyl esters or ethers of sorbitan, or of sugars. As sorbitan esters, mention may be made, for example, of sorbitan isostearate, oxyalkylenated fatty acid and sorbitan esters, sugar esters such as sucrose stearate, and mixtures thereof.

In particular, the polymers ii) cyclic non-aromatic non-ionic polysaccharides may also be chosen from fatty alcohol and sugar ethers, in particular alkylpolyglucosides (APGs), such as decylglucoside and laurylglucoside, marketed for example by the company BASF under the respective names Plantaren 2000 ^® and Plantaren 1200 ^® , cetostearylglucoside optionally in a mixture with cetostearyl alcohol, marketed for example under the name Montanov 68 ^® by the company Seppic, under the name Tegocare CG90 ^® by the company Evonik and under the name Emulgade KE3302 ^® by the company BASF, as well as arachidyl glucoside, for example in the form of the mixture of arachidic and behenic alcohols and arachidylglucoside marketed under the name Montanov 202 ^® by the Seppic company.

In particular, the nonionic acyclic polymers ii) may be chosen from alkyl esters or ethers of polyols, such as glycerol. As glycerol ester, mention may be made, for example, of polyglycerol isostearate, such as the product marketed under the name Isolan GI 34 ^® by the company Evonik. Mention may also be made of polyoxyalkylenated, more particularly polyoxyethylenated and/or polyoxypropylenated, fatty acid esters of glycerol, such as the ester of polyethylene glycol and stearic acid with the INCI name PEG-100 Stearate, polyoxyalkylenated, in particular polyoxyethylenated and/or polyoxypropylenated, fatty acid esters, optionally in combination with a fatty acid ester of glycerol such as the PEG-100 Stearate/Glyceryl Stearate mixture.

Non-ionic acyclic polymers (ii) may also refer to oxyalkylenated, in particular oxyethylenated and/or oxypropylenated, fatty alcohol ethers.

In particular, the non-aromatic cyclic polymers ii) are chosen from anionic polysaccharides are chosen from sulfated polysaccharides and carboxylate polysaccharides.

The polysaccharide may be optionally acetylated. The acetylation rate may range from 1% to 40% by weight (weight rate of acetyl units relative to the total weight of the polymer ii).

According to a preferred embodiment, the polymer ii) is chosen from polysaccharides having a weight average molecular weight ranging from 2000 to 20 x 10 ⁶ Daltons, preferably between 3000 and 10 x 10 ⁶ Da, more preferably between 5000 and 5 x 10 ⁶ Da and even more preferably between 10,000 and 1 x 10 ⁶ Da.

Among the sulfated polysaccharides, mention may be made of ulvans, dextran sulfates, carrageenans, in particular lambda carrageenan and naked carrageenan, fucoidans, preferably ulvans, dextran sulfates, carrageenans, in particular lambda carrageenan, and mixtures thereof.

Advantageously, the sulfation rate of the polysaccharides can range from 1% to 90% by weight, relative to the weight of the polysaccharide. Preferably, this sulfation rate can range from 2% to 85% by weight.

In particular, the sulfated polysaccharides ii) may also be chosen from ulvans, which are sulfated polysaccharides derived from algae, in particular red or green algae.

Ulvans can be obtained from many species of Ulva including Ulva lactuca, Ulva rigida, Ulva armoricana, Ulva rotundata and Ulvaria obscura, as well as several species of Enteromorpha, particularly Enteromorpha compressa, Enteromorpha intestinalis and Enteromorpha ramulosa.

Ulvans consist primarily of rhamnose, glucuronic acid, glucose, galactose, and xylose and also include sulfate groups. They may also include varying amounts of galacturonic acid, iduronic acid, and mannose.

Ulvans generally have a polysaccharide sulfation rate ranging from 1% to 30% by weight, relative to the weight of the polysaccharide, and more particularly from 10% to 20% by weight.

Rhamnose is usually sulfated at position 3. Xylose can also be partially sulfated. Most of the constituent sugars are distributed in repetitive sequences. The two major ones are disaccharide sequences, one called 3-sulfated ulvanobiuronic acid type A (A3s) comprising rhamnose 3-sulfate linked to glucuronic acid by a 1→4 bond, the other called 3-sulfated ulvanobiuronic acid type B (B3s) comprising rhamnose 3-sulfate linked to iduronic acid by a 1→4 bond.

The relative proportion of sugars varies depending on the location of the ulva harvest, the species and also the time of harvest in the year. For the extraction of ulvans from ulva, one can refer to the extraction processes described in Carbohydrate Research 274 (1995) 251-261 or in Hydrobiologia 326/327;473-480,1996.

According to a particular embodiment, the polymer(s) ii) are or contain at least one ulvan.

According to a particular embodiment, the mass of the ulvan(s) is between 10,000 and 1,500,000, preferably between 20,000 and 1,000,000.

In particular, the sulfated polysaccharides ii) may also be chosen from dextrans sulfates derived from dextran.

Dextran is a complex branched glucan (polysaccharide derived from the condensation of glucose), originally derived from wine. The IUPAC defines dextrans as “branched poly-α-d-glucosides of microbial origin whose glycosidic bonds are predominantly C-1 → C-6”. Dextrans chains are of variable lengths (from 3 to 2000 kilodaltons).

The main chain of the polymer consists of α-1,6 glycosidic bonds between the glucose monomers, with branches of α-1,3 bonds. This characteristic branching distinguishes a dextran from a dextrin, which is a straight-chain glucose polymer linked by α-1,4 or α-1,6 bonds.

In particular, we can use dextran sulfate sold under the trade name Dextran sulfate 10 sodium salt CG, by the company PK chemicals.

The molar mass of dextran sulfate is preferably between 2,000 and 200,000, preferably between 2,000 and 100,000, and more preferably between 3,000 and 80,000.

Among the carboxylate polysaccharides ii), we can cite alginates.

Alginates are obtained from brown algae such as kelp or fucus. Alginates are preferably sodium alginates or calcium alginates.

Alginates are polysaccharides derived from mannuronate or mannuronic acid, some of which are possibly acetylated, and guluronate or guluronic acid. The bond is of the beta 1-4 type.

Preferably, the mass Mw of the alginates is less than 200,000, more preferably less than 100,000, even more preferably less than 75,000, better still less than 50,000.

According to a particular embodiment, the polymer(s) ii) of the invention are chosen from nonionic polymers, in particular nonionic polysaccharides, and more particularly polysaccharides modified by the presence of at least one aliphatic hydrocarbon chain, cyclic or non-cyclic, linear or branched, saturated or unsaturated, aromatic or not, comprising from 2 to 30 carbon atoms optionally substituted by one or more atoms or groups a) halogen, such as chlorine or bromine, b) (hetero)aryl, such as phenyl or furyl, c) (hetero)cycloalkyl, such as anhydride, epoxide or dithiolane, d) RX with R representing a group chosen from i) cycloalkyl such as cyclohexyl, and/or ii) (di)alkylamino and/or optionally interrupted by one or more heteroatoms or groups chosen from a') heteroatoms, such as O, S, N(Ra), and Si(Rb)(Rc), b') S(O)r, (thio)carbonyl, c') or the combinations of a') with b'), such as (thio)ester, (thio)amide, (thio)urea, sulfonamide with r being 1 or 2, Ra representing a hydrogen atom, or a (C ₁ -C ₄ )alkyl group, or aryl(C ₁ -C ₄ )alkyl, such as benzyl, preferably Ra represents a hydrogen atom, Rb and Rc, identical or different, represent a (C ₁ -C ₄ )alkyl or (C ₁ -C ₄ )alkoxy group.

Modified polysaccharides include those obtained from native gums, such as those from tree or berry exudates, algae, seeds or tubers, fungi, bacteria, animal organisms, plants, which have been modified by physical, chemical or enzymatic reactions.

In particular, native gums can be chosen from:

- gum arabic (branched polysaccharide of galactose, arabinose, rhamnose and glucuronic acid);

- gum ghatti (polymer derived from arabinose, galactose, mannose, xylose and glucuronic acid);

- karaya gum (polymer derived from galacturonic acid, galactose, rhamnose and glucuronic acid);

- gum tragacanth (or tragacanth) (polymer of galacturonic acid, galactose, fucose, xylose and arabinose);

- agar (polymer derived from galactose and anhydrogalactose);

- alginates (polymers of mannuronic acid and glucuronic acid);

- carrageenans and furcellerans (polymers of galactose sulfate and anhydrogalactose sulfate);

- guar gum (polymer of mannose and galactose);

- carob gum (polymer of mannose and galactose);

- fenugreek gum (polymer of mannose and galactose);

- tamarind gum (polymer of galactose, xylose and glucose);

- konjac gum (polymer of glucose and mannose);

- xanthan gum (polymer of glucose, mannose acetate, mannose/pyruvic acid and glucuronic acid) or dehydroxanthan gum;

- gellan gum (polymer of partially acylated glucose, rhamnose and glucuronic acid);

- scleroglucan gum (glucose polymer);

- cellulose (glucose polymer);

- starch (glucose polymer);

- inulin; and

- pectin.

In particular, the modified polysaccharides are derived from: i) gum arabic; ii) gum ghatti; iii) gum karaya; iv) gum tragacanth; v) agar; vi) alginates; vii) carrageenans and furcellerans; viii) guar gum; ix) locust bean gum; x) fenugreek gum; xi) tamarind gum; xii) konjac gum; xiii) xanthan gum or dehydroxanthan gum; xiv) gellan gum; xv) scleroglucan gum; xvi) cellulose; xvii) starch; xviii) inulin; and xix) pectin.

Starch molecules xvii) can have a botanical origin from cereals or tubers. Thus, starches are for example chosen from corn, rice, cassava, barley, potato, wheat, sorghum, pea starches.

Starches can be modified chemically or physically, in particular by one or more of the following reactions: pregelatinization, oxidation, crosslinking, esterification, etherification, amidation, heat treatments.

Nonionic modified polysaccharides can be modified physically or chemically. Physical treatment includes, for example, temperature.

Chemical treatments include esterification, etherification, amidation, oxidation, metathesis and addition reactions.

According to a particular embodiment, the modified polysaccharides are polysaccharide ethers called alkyl polysaccharides whose alkyl radical comprises between 2 and 30 carbon atoms, preferably between 2 and 10 carbon atoms, more preferably between 2 and 6 carbon atoms.

Preferably, the alkyl polysaccharides according to the invention are derived from cellulose or guar or their mixtures.

According to a particular embodiment, the modified polysaccharides are alkylcelluloses whose linear or branched alkyl residue comprises between 1 to 10 carbon atoms, in particular between 2 and 6 carbon atoms, preferably between 2 and 3 carbon atoms.

Alkylcellulose is an alkyl ether of cellulose comprising a chain consisting of β-anhydroglucose units linked together by acetal bonds. Each anhydroglucose unit has three replaceable hydroxyl groups, all or part of these hydroxyl groups being able to react according to the following reaction:

Cell-OM + R-Hal Cell-OR + MHal

with Hal representing a halogen, such as Cl, with M representing a cationic counterion, such as alkali metal Na or K, or alkaline earth metal, preferably an alkali metal, such as Na, Cell representing a polysaccharide radical, such as cellulose, where R represents a linear or branched alkyl group, comprising from 1 to 10 carbon atoms, preferably between 2 and 3 carbon atoms, such as methyl or ethyl, and MHal the salt generated such as sodium chloride.

Advantageously, the alkylcellulose is chosen from ethylcellulose and propylcellulose.

According to a particular embodiment, the polysaccharide ethers are alkyl guars, in other words guar gums viii) modified by substitution of hydroxy hydrogen by a linear or branched alkyl group, comprising between 1 to 10 carbon atoms, in particular between 2 and 6 carbon atoms, preferably between 2 and 3 carbon atoms, such as 2 carbon atoms.

The alkyl guar polymers used according to the invention are preferably ethyl guar.

Ethyl guar is known by the INCI name: C1-C5 alkyl galactomannan.

Alkylated guar gums (with _C1 - _C6 alkyl group), including ethyl guar, are described in particular in patent application EP 708114 and document RD9537807 (October 1995), as well as their preparation process.

According to a particular embodiment, the modified polysaccharides are polysaccharide esters, in particular esters obtained by reaction between at least one polysaccharide such as dextrin with at least one linear or branched saturated or unsaturated acid comprising from 2 to 30 carbon atoms, in particular from 10 to 30 carbon atoms.

According to a particular embodiment of the invention, the modified polysaccharide(s) are chosen from polysaccharide mono- or polyalkyl esters.

Among the mono or polyalkyl esters of saccharide or polysaccharide suitable for implementing the invention, mention may be made of alkyl or polyalkyl esters of dextrin or inulin.

This may include in particular a mono- or poly-ester of dextrin (dextrin being derived from starch xvii) and at least one fatty acid (such as R-C(O)-OH) and in particular corresponding to the following formula (XVIII):

formula (XVIII) in which:

- n is an integer greater than or equal to 2, preferably ranging from 3 to 200, in particular ranging from 20 to 150, and in particular ranging from 25 to 50,

- R ₁ , R ₂ and R ₃ , identical or different, are chosen from hydrogen or an acyl group (RC(O)-) in which the radical R is a hydrocarbon group, linear or branched, saturated or unsaturated, having from 7 to 29, in particular from 7 to 21, in particular from 11 to 19, more particularly from 13 to 17, or even 15, carbon atoms, it being understood that at least one of said radicals R ₁ , R ₂ or R ₃ is other than hydrogen.

In particular, R ₁ , R ₂ and R ₃ represent a hydrogen atom or an acyl group (RC(O)-) in which R is a hydrocarbon radical as defined above, provided that at least two of said radicals R ₁ , R ₂ or R ₃ are other than hydrogen.

The set of radicals R ₁ , R ₂ and R ₃ can represent an identical or different acyl group (RC(O)), and the acyl groups are notably identical.

In particular, n previously exposed advantageously varies from 25 to 50, in particular is equal to 38 in the general formula of the saccharide ester usable in the present invention.

In particular, when the radicals R ₁ , R ₂ and/or R ₃ , which are identical or different, represent an acyl group (RC(O)), derived from fatty carboxylic acid RC(O)OH preferably chosen from caprylic, capric, lauric, myristic, palmitic, stearic, arachic, behenic, isobutyric, isovaleric, 2-ethylbutyric, ethylmethylacetic, isoheptanoic, 2-ethylhexanoic, isononanoic, isodecanoic, isotridecanoic, isomyristic, isopalmitic, isostearic, isoaracic, isohexanoic, decenoic, dodecenoic, tetradecenoic, myristoleic, hexadecenoic, palmitoleic, oleic, elaidic, asclepinic, gondoleic, eicosenoic acids, sorbic, linoleic, linolenic, punicic, stearidonic, arachidonic, stearolic, and mixtures thereof.

Preferably, at least one dextrin palmitate is used as the ester of dextrin and fatty acid(s). This can be used alone or in a mixture with other esters.

Preferably, the dextrin and fatty acid ester has a degree of substitution less than or equal to 2.5 based on a glucose unit, in particular varying from 1.5 to 2.5, preferably from 2 to 2.5. The weight-average molecular weight of the dextrin ester may be in particular from 10,000 to 150,000, in particular from 12,000 to 100,000, and even from 15,000 to 80,000.

Preferably, the modified polysaccharide(s) of the invention are dextrin esters, more preferably dextrin palmitates.

Dextrin esters, particularly dextrin palmitates, are commercially available under the name Rheopearl KL2 ^® , MKL2 ^® , TL ^® or KL ^® from Chiba Flour.

According to a particular embodiment, the modified polysaccharide is a modified dextrin, preferably a dextrin ester, more particularly an ester of dextrin and saturated or unsaturated, linear or branched C ₁₂ -C ₂₄ fatty acid.

Preferably, the dextrin ester is chosen from esters of saturated or unsaturated, linear or branched C ₁₄ -C ₂₄ fatty acids, such as myristic acid, palmitic acid or their mixture.

According to a particular embodiment, the dextrin ester is chosen from dextrin palmitate such as Rheopearl KL2 ^® and Rheopearl TL2 ^® , marketed by Chiba Flour, dextrin myristate, such as that marketed under the reference Rheopearl MKL2 ^® by Chiba Flour, dextrin palmitate/ethylhexanoate marketed under the reference Rheopearl TT2 ^® , dextrin palmitate/hexyldecanoate marketed under the reference Rheopearl WX, or mixtures thereof.

According to a particular embodiment, the modified polysaccharide is a modified inulin, preferably an inulin ester, more particularly an ester of inulin and saturated or unsaturated, linear or branched C ₁₂ -C ₂₄ fatty acid.

Preferably, the inulin ester is chosen from esters of saturated or unsaturated, linear or branched C ₁₄ -C ₂₄ fatty acids, such as myristic acid, palmitic acid, stearic acid, preferably stearic acid, or mixtures thereof.

According to a particular embodiment, the inulin ester is a stearoyl inulin, such as the references Rheopearl ISK2 ^® and Rheopearl ISL2 ^® , marketed by Chiba Flour, or their mixtures.

According to one embodiment, the modified polysaccharide is a modified cellulose, preferably a cellulose ester, more particularly an ester of cellulose and a saturated or unsaturated, linear or branched C ₂ -C ₂₄ acid.

Preferably, the cellulose ester is chosen from esters of saturated or unsaturated, linear or branched _C2 - _C10 , preferably _C2 - _C6 , in particular _C2 - _C4 , acids, such as acetic acid, butyric acid or their mixture.

According to a particular embodiment, the cellulose ester is a cellulose acetate butyrate, such as the reference Eastman Cellulose Acetate Butyrate ^® , marketed by Eastman Chemical.

According to a particular embodiment, the polymer(s) ii) are chosen from nonionic polymers, in particular nonionic polysaccharides, more particularly inulins modified by hydrophobic chains, such as alkylcarbamate groups, in particular _C8 - _C18 alkyl carbamate, and more particularly laurylcarbamate.

As an example of these compounds, we can notably cite the product sold under the name Inutec SL1 by the company Creachem.

Among the polysaccharide esters, we can also mention pullulan esters. Pullulan is a polysaccharide consisting of maltotriose units.

According to one embodiment, the modified polysaccharides are polysaccharide esters. By polysaccharide esters is meant polysaccharides in which at least one of the hydroxy radicals is esterified by an acid to form ester groups -O-C(O)-R or -C(O)-OR, in which R denotes a saturated or unsaturated radical of 2 to 30 carbon atoms, in particular 11 to 19 carbon atoms, preferably 12 to 17 carbon atoms, such as 13 carbon atoms.

In particular, the polysaccharide ester is myristoyl pullulan.

According to a particular embodiment, the polymer(s) ii) comprise at least one cationic modified polysaccharide.

Preferably, chemical or physical treatments to obtain at least one cationic group are applied to guar gums, carob gums, starches and celluloses.

The cationic groups may be of primary, secondary, tertiary or quaternary amine type, preferably quaternary, and comprise a _C6 - _C30 aliphatic chain.

According to a particular embodiment, the modified polysaccharide(s) ii) are chosen from quaternized (poly)hydroxyethylcelluloses modified by groups comprising at least one aliphatic chain (or fatty chain), such as alkyl, arylalkyl, alkylaryl groups comprising at least 8 carbon atoms, or mixtures thereof.

The alkyl radicals carried by quaternized celluloses or hydroxyethylcelluloses preferably contain from 8 to 30 carbon atoms.

Aryl radicals preferably denote phenyl, benzyl, naphthyl or anthryl groups. Examples that may be mentioned are quaternized alkylhydroxyethylcelluloses with C ₈ -C ₃₀ fatty chains, such as the products Quatrisoft LM 200 ^® , Quatrisoft LM-X 529-18-A ^® , Quatrisoft LM-X 529-18-B ^® (C ₁₂ alkyl) and Quatrisoft LM-X 529-8 ^® (C ₁₈ alkyl) sold by Dow Corning, the products Crodacel QM ^® , Crodacel QL ^® (C ₁₂ alkyl) and Crodacel QS ^® (C ₁₈ alkyl) sold by Croda and the product Softcal SL 100 ^® sold by Dow Corning.

According to a particular embodiment, the modified polysaccharide(s) ii) are chosen from guar gums modified by C ₁ -C ₂₀ (poly)hydroxyalkylammonium groups, preferably C ₁ -C ₆ (poly)hydroxyalkyl.

Examples that may be mentioned include hydroxymethyltrimmonium, hydroxyethyltrimmonium, hydroxypropyltrimmonium and hydroxybutyltrimmonium halide groups, preferably hydroxypropyltrimonium halide, preferably chloride.

Such cationic guar gums modified with hydroxyalkylammonium groups are for example sold by the company Solvay under the trade names Cationic Jaguar ^® C-14S Guar Hydroxypropyltrimonium Chloride, F Jaguar ^® C-13S Guar Hydroxypropyltrimonium Chloride, F Jaguar ^® C-17 Guar Hydroxypropyltrimonium Chloride, Jaguar ^® Excel Guar Hydroxypropyltrimonium Chloride, Jaguar ^® C-500 STD Guar Hydroxypropyltrimonium Chloride, Jaguar ^® C-162 Hydroxypropyl Guar Hydroxypropyltrimonium Chloride, Jaguar ^® Optima Guar Hydroxypropyltrimonium Chloride, and Jaguar ^® LS Hydroxypropyl Guar Hydroxypropyltrimonium Chloride.

According to a particular embodiment, the cationic non-aromatic cyclic polymers ii) are in particular polysaccharides with amine groups, such as chitosans.

Preferably, the amine groups are primary, secondary, or tertiary amines, preferably primary.

Polysaccharides with amino groups also include their organic or mineral acid salts, their α or β anomers, their optical isomers of L or D configuration and their solvates, such as hydrates.

According to a preferred embodiment, the polysaccharide(s) with amine group(s) have an average molecular weight PM less than or equal to 400 KDa.

According to a particular embodiment, the polysaccharide(s) with amine group(s) is (are) chosen from those with _C5 - _C7 osidic units, as well as their organic or mineral acid salts, their α or β anomers, their optical isomers of L or D configuration and their solvates, such as hydrates.

More particularly, the polysaccharide(s) with amine group(s) has a _C6 osidic unit with amine group(s); these polysaccharides with amine group(s) are then called polyhexosamines.

According to a particular embodiment, the osidic units of the polysaccharide with amine group(s) are of anomeric β (beta) configuration and/or D configuration.

According to a particular embodiment, the osidic units of the polysaccharide with amine group(s) are linked together between the carbon 1 atoms of one osidic unit and the carbon 4 atoms of the other osidic unit, denoted (1→4), such as the polysaccharide with amine group(s) of the following formula (B), as well as their organic or mineral acid salts, their α or β anomers, their optical isomers of L or D configuration and their solvates, such as hydrates:

formula (B) in which:

- the radicals R _a , R _b , R _c of each osidic unit can be identical or different;

- n is an integer greater than or equal to 2, particularly inclusively between 3 and 3000;

- R _a , R _b , and R _c , which may be identical or different, represent a group i) hydroxy, ii) (C ₁ -C ₄ )alkoxy, the alkyl group of which may be optionally substituted in particular by one or more hydroxy groups, iii) carboxy, and iv) NR ₁ R ₂ with R ₁ and R ₂ as defined above, in particular R ₁ and R ₂ are chosen from the hydrogen atom and –C(O)-R'1 in which R'1 is as defined above; preferably R ₁ and R ₂ represent an i) hydrogen atom or ii) –C(O)-R'1 and R'1 representing a (C ₁ -C ₄ )alkyl group such as methyl;

it being understood that at least one of the radicals R_has, R_bor R_cof at least one osidic unit represents an NR group₁R₂and that at least one of the NR groups₁R₂of at least one osidic unit represents an NH group₂ ; preferably R_hasof at least one osidic unit represents an NR group₁R₂with R₁which represents a hydrogen atom and R₂is selected from i) a hydrogen atom or ii) a –C(O)-R’1 group, and R_band R_crepresent a hydroxy group, it being understood that at least one of the NR groups₁R₂of at least one osidic unit represents an NH group₂.

More particularly, the polysaccharide(s) with amine group(s) of the invention is (are) of the following formula (B1), as well as their organic or mineral acid salts, their α or β anomers, their optical isomers of L or D configuration and their solvates, such as hydrates:

formula (B1) in which:

- R' represents a hydrogen atom or a (C ₁ -C ₄ )alkylcarbonyl group, such as acetyl CH ₃ -C(O)-;

- R'' represents a hydrogen atom or a (C ₁ -C ₄ )alkyl group optionally substituted by a carboxy group, such as –CH(CO ₂ H)-CH ₃ ;

- n is an integer greater than or equal to 2, particularly inclusively between 3 and 3000;

it being understood that in the polysaccharide (B1) at least one osidic unit carries an amino group NH ₂ and at least one other osidic unit carries at least one group N(H)-R' with R' representing a (C ₁ -C ₄ )alkylcarbonyl group, such as acetyl CH ₃ -C(O)-.

Preferably, the osidic units of formula (B) or (B1) are of D configuration or also called D-glucopyrane.

In particular, the units of formula (B) or (B1) are of anomeric β (beta) configuration.

According to a particular embodiment, the polysaccharides of the invention are chosen from the compounds of the following formula (B2) as well as their acid salts, organic or mineral, and their solvates such as hydrates:

formula (B2) in which:

- R _a , R _b , and R _c , are as defined for (B) previously;

- the radicals R _a , R _b , R _c of each osidic unit can be identical or different;

- n is an integer greater than or equal to 2, particularly inclusively between 3 and 3000, more particularly between 5 and 2500, preferably between 10 and 2300;

it being understood that in the polysaccharide (B2) at least one of the radicals R_has, R_bor R_cof at least one osidic unit represents an NR group₁R₂and that at least one of the NR groups₁R₂of at least one osidic unit represents an NH group₂ ; preferably at least one osidic unit carries an R group_hasamino NH₂and at least one other osidic unit carries an R group_haswhich represents -N(H)-R’ with R’ representing a group (C₁-C₄)alkylcarbonyl, such as acetyl CH₃-CO)-.

Preferably, the polysaccharide(s) with amine group(s) is (are) chosen from chitin and chitosan and their derivatives, preferably chitosan.

More particularly, the polysaccharide(s) with amine group(s) is (are) chosen from those of the following formula (B3) as well as their organic or mineral acid salts, and their solvates such as hydrates:

formula (B3) in which:

- R ₁ and R ₂ are as defined in formulas (B), (B1) or (B2); and

- n is an integer greater than or equal to 2, particularly inclusively between 3 and 3000, more particularly between 5 and 2500, preferably between 10 and 2300;

it being understood that in the polysaccharide of formula (B3) at least one osidic unit carries an amino group NH ₂ and at least one other osidic unit carries a group N(H)-R' with R' representing a (C ₁ -C ₄ )alkylcarbonyl group such as acetyl CH ₃ -C(O)-.

More particularly, the polysaccharide(s) with amine group(s) of the invention is (are) chosen from chitosans of the following formula (B4) as well as their organic or mineral acid salts, and their solvates such as hydrates:

formula (B4) in which:

- R' ₁ representing a (C ₁ -C ₄ )alkyl group, such as methyl;

- n is an integer greater than or equal to 2, particularly inclusively between 3 and 3000;

- p is greater than 0 and ranges up to 0.5, preferably from 0.05 to 0.3, and better from 0.1 to 0.20, such as 0.15, with m + p being equal to 1;

it being understood that in chitosan at least one saccharide unit carries an amino group NH ₂ and at least one other saccharide unit carries a group N(H)-R' ₁ with R' representing a (C ₁ -C ₄ )alkylcarbonyl group, such as acetyl CH ₃ -C(O)-.

For example, when m = 0.7, p = 0.3 this means that 70% of the amine groups are free (unsubstituted), and 30% of the amino groups are N-alkyl(C ₁ -C ₄ )carbonylated, in particular N-acetylated, corresponding to the chitosan polymer of formula:

with n as defined previously.

In particular, the polysaccharide(s) with amine group(s) of the invention is (are) chosen from chitosans, salified using organic acid, preferably using monocarboxylic acid of formula (I) as defined below or polycarboxylic acid of formula (II) as defined below, even more preferably salified using carboxylic acid of formula (I), such as lactic acid.

Formula (I) is represented by the formula RC(O)-OH, with R representing a (hetero)aryl group, such as phenyl, (hetero)aryl(C ₁ -C ₄ )alkyl, such as benzyl, or (C ₁ -C ₃₀ )alkyl or an unsaturated C ₂ -C ₃₀ radical (i.e. comprising at least one ethylenic unsaturation, preferably one ethylenic unsaturation), said alkyl group or unsaturated C ₂ -C ₃₀ radical being optionally interrupted and/or optionally substituted, preferably by one or more hydroxy groups and unsubstituted by one or more amino radicals, R preferably denoting a (C ₁ -C ₆ )alkyl group optionally interrupted and/or optionally substituted by 1, 2 or 3 hydroxy groups, preferably R represents a (C ₁ -C ₄ )alkyl group, such as methyl or ethyl; in particular, the organic monocarboxylic acids (I) are chosen from acetic acid, glycolic acid, and lactic acid, more particularly from acetic acid and lactic acid, and the polycarboxylic acids of the following formula (II):

formula (II) in which A represents a polyvalent hydrocarbon group comprising from 1 to 30 carbon atoms, saturated or unsaturated, cyclic or non-cyclic, aromatic or non-aromatic, optionally interrupted by one or more heteroatoms, such as oxygen and/or optionally substituted in particular by one or more hydroxyl groups; and t represents an integer between 1 and 5 inclusive.

Preferably, A represents a divalent ( _C1 - _C6 )alkylene group optionally substituted in particular by one or more hydroxy groups and not substituted by at least one amino radical, and t is 1, 2 or 3.

Preferably, the polycarboxylic acids of formula (II) are chosen from tartaric acid, succinic acid, fumaric acid and citric acid and more particularly chosen from tartaric acid, succinic acid, fumaric acid and citric acid, and amino acids comprising more carboxylic acid radicals than amino groups, such as gamma-carboxyglutamic acid, aspartic acid, glutamic acid, in particular gamma-carboxyglutamic acid; in particular the salts of monocarboxylic acids other than pyrrolidonecarboxylic acid, 100 EO and 500 EO ethoxylated stearic acids and linoleic acid.

According to a particular embodiment, the polysaccharide(s) with amine group(s) are chosen from a mixture of polysaccharide(s) with amine group(s), one of which is a chitosan or one of its organic or mineral acid salts, preferably its organic acid salts, more particularly chosen from lactic acid, its α or β anomers, its optical isomers of L or D configuration and its solvates, such as hydrates.

According to a particular embodiment, the polysaccharide(s) with amine group(s) is a single polysaccharide with amine group(s), in particular a mixture of chitosan or one of their organic or mineral acid salts, or more particularly their organic acid salts, more particularly chosen from their lactic acid salt, their α or β anomers, their optical isomers of L or D configuration and their solvates, such as hydrates.

According to a particular embodiment, the polysaccharide(s) with amine group(s) is a single polysaccharide with amine group(s), in particular a chitosan or one of its organic or mineral acid salts, or more particularly its organic acid salts, preferably chosen from its lactic acid salt, its α or β anomers, its optical isomers of L or D configuration and its solvates, such as hydrates.

According to a particular embodiment, the polymer(s) ii) are chosen from acyclic polymers, preferably from anionic acyclic polymers.

By way of example, mention may be made of polymers ii) chosen from amino acids modified by at least one _C8 - _C30 hydrocarbon chain, preferably _C8 - _C24 , and their salts, in particular acyl glutamic acids (INCI name: acyl glutamic acid) or one of their salts, such as acyl glutamates, in particular stearoyl glutamic acid or one of its salts, more particularly sodium stearoyl glutamate (INCI name).

Such compounds are marketed under the name Amisoft by the company Ajinomoto, and in particular under the references Amisoft CA, Amisoft LA, Amisoft HS 11 PF, Amisoft MK-11, Amisoft LK-11, Amisoft CK-11, or under the name Eumulgin SG by the company Cognis.

According to a particular embodiment, the polymer(s) ii) are chosen from acyclic polyamino and hydrocarbon polymers. Such polymers do not comprise silicon atoms. These polymers are preferably chosen from amino polymers, in particular having a weight-average molecular weight ranging from 2000 g.mol ^-1 to 1,000,000 g.mol ^-1 , preferably ranging from 2000 g.mol ^-1 to 500,000 g.mol ^-1 , and preferentially ranging from 2000 g.mol ^-1 to 100,000 g.mol ^-1 .

In particular, the polyamine polymer(s) may be chosen from diamine polymers, and more particularly from polyether diamines, in particular of formula H ₂ N-ALK-O-[ALK'-O] _m -ALK''-NH ₂ with ALK, ALK' and ALK'', identical or different, representing a linear or branched (C ₁ -C ₆ )alkylene group, and m representing an integer greater than or equal to 0, such as 4,7,10-trioxa-1,13-tridecanediamine or the compounds known under the reference Jeffamine from the company Hunstman, and more particularly α, ω-diamine polyethylene glycol and/or polypropylene glycol (with an amine function at the end of the chain), for example sold under the names Jeffamine D-230, D-400, D-2000, D-4000, ED-600, ED-9000, ED-2003.

In particular, the polyamino polymer(s) may be chosen from triamino polymers, namely containing three primary and/or secondary amine groups, preferably primary (NH ₂ ).

More particularly, they are chosen from triamine polyethers, in particular of formula ALK'''[(O-ALK')m-NH ₂ ] ₃ with ALK' as defined above and ALK''', representing a trivalent (C ₁ -C ₆ )alkylene group, linear or branched, and m representing an integer greater than or equal to 0.

As (poly)amino compounds which are triaminated, triaminated polyethers are particularly cited, and in particular α, ω-diamine polyethylene glycol and/or polypropylene glycol (with amine function at the end of the chain), for example sold under the names Jeffamine T-403.

According to a particular embodiment, the (poly)amine compound(s) comprise more than three primary and/or secondary amine groups, preferably primary (NH ₂ ).

In particular, the (poly)amine compound(s) are chosen from poly(meth)acrylates or poly(meth)acrylamides bearing side primary or secondary amine functions, more particularly chosen from poly(3-aminopropyl)methacrylamide and poly(2-aminoethyl)methacrylate.

According to a particular embodiment, the polyamine compound(s) are chosen from:

- poly(alkylene (C ₂ -C ₅ )imines), and preferably among polyethyleneimines and polypropyleneimines, in particular poly(ethyleneimine), in particular those sold under the reference 408700 by the company Aldrich Chemical or under the reference 408727 by the company Aldrich Chemical (example PM = 25000) or under the trade name Lupasol by BASF, in particular with a molecular weight of between 1,200 and 30,000,

- poly(allylamine), in particular that sold under the reference 479136 by the company Aldrich Chemical,

- polyvinylamines and their copolymers, in particular with vinylamides, in particular vinylamine/vinylformamide copolymers,

- polyamino acids with _NH2 groups such as polylysine, in particular that sold by the company JNC Corporation (formerly Chisso),

- amino dextran, in particular that sold by the company CarboMer Inc,

- polyvinyl amino alcohol, in particular that sold by the company CarboMer Inc,

- copolymers based on acrylamido( _C1 - _C6 )alkylamine, in particular based on acrylamidopropylamine, and

- their mixtures.

As amino polymers, α, ω-diamine polytetrahydrofurans (or polytetramethylene glycol) and α, ω-diamine polybutadienes can also be mentioned.

According to a particular embodiment, the (poly)amino compounds are chosen from hyperbranched polymers comprising at least one amino group and dendrimers carrying at least one amino group, in particular polyamidoamine PAMAM dendrimers with an ethylenediamine core and a terminal amine function.

According to a particular embodiment, the polymer(s) ii) are chosen from polyamino acids, and preferably from proteins.

Preferably, the proteins are of plant origin. As examples of polymers ii) chosen from plant proteins, mention may be made of soy proteins.

According to a preferred embodiment, the molar mass of the non-aromatic cyclic polymers ii) is less than 2,000,000.

According to another embodiment, when the polymer(s) ii) are anionic polysaccharides carrying carboxylate groups, their molar mass is less than 400,000.

The acyclic polymers ii) may be anionic, cationic or nonionic, preferably anionic, more preferably carrying carboxyl, carboxylate, sulfate, sulfonic acid, sulfonate, phosphate, phosphonic acid, phosphonate group(s), preferably chosen from carboxylates and carboxylic acids.

According to a particular embodiment, the acyclic polymers ii) are anionic, in particular carrying carboxylic groups or carboxylates of alkali or alkaline earth metals such as sodium, and are chosen from homo or copolymers of (meth)acrylic acid.

(Meth)acrylic acid copolymers are in particular copolymers of (meth)acrylic acid with alkyl (poly)ether (meth)acrylates, in particular copolymers of (meth)acrylic acid and POE/POP (meth)acrylate, for example polyether polycarbonate, sodium salt in aqueous solution for example marketed under the name “RSY 15007 Cosmetic Version” by the company Arkema-Coatex.

According to a preferred embodiment, the polymer(s) ii) are chosen from:

- lignosulfonic acid, lignosulfonates, polystyrene sulfonic acid, polystyrene sulfonates, anionic polyanethol derivatives, in particular polyanethol sulfonates, and mixtures thereof,

- alkyl esters or ethers of polyols, in particular glycerol,

- anionic polysaccharides, preferably chosen from sulfated polysaccharides, in particular ulvans, dextran sulfates, carrageenans, and mixtures thereof, and carboxylate polysaccharides, in particular alginates,

- cationic polysaccharides, preferably chosen from polysaccharides with amine groups, in particular chitosans.

- modified polysaccharides, in particular chosen from polysaccharide esters, and preferably from pullulan esters,

- poly(alkylene (C ₂ -C ₅ )imines), and preferably among polyethyleneimines and polypropyleneimines, in particular poly(ethyleneimine),

- polyamino acids, and preferably among proteins,

- anionic acyclic polymers, bearing carboxylic groups or carboxylates of alkali or alkaline earth metals such as sodium, and chosen from homo or copolymers of (meth)acrylic acid, preferably from sodium polymethacrylates and copolymers of (meth)acrylic acid with alkyl (poly)ether (meth)acrylates, in particular copolymers of (meth)acrylic acid and POE/POP (meth)acrylate, and

- their mixtures.

According to a preferred embodiment, the polymer(s) ii) are chosen from:

- lignosulfonates,

- polystyrene sulfonates,

- polyanethol sulfonates,

- alkyl esters or ethers of glycerol,

- dextran sulfates,

- lambda carrageenan,

- naked carrageenan,

- alginates,

- chitosans,

- pullulan esters,

- polyethyleneimines,

- proteins,

- sodium polymethacrylates,

- copolymers of (meth)acrylic acid and POE/POP (meth)acrylate, and

- their mixtures.

In particular, a composition according to the invention may comprise from 0.005% to 40% by weight, preferably from 0.05% to 20% by weight, of polymer(s) ii), relative to the total weight of the composition.

According to a particular embodiment, the mass ratio i)/ii) is greater than 1.

According to one embodiment, the mass ratio i)/ii) is between 1/1 and 1/0.001, preferably between 1/1 and 1/0.005, more preferably between 1/1 and 1/0.01.

Solvent iii)

According to a particular embodiment of the invention, the compositions according to the invention comprise at least one solvent iii).

The solvent(s) may be polar or nonpolar, protic or aprotic, volatile or nonvolatile.

According to a particular embodiment, the composition according to the invention comprises a single solvent iii).

According to a particular embodiment, the composition according to the invention comprises a mixture of solvents iii).

According to a particular embodiment, the composition according to the invention comprises a mixture of solvents iii) miscible with each other.

According to a particular embodiment, the composition according to the invention comprises a mixture of solvents iii) immiscible with each other.

According to a particular embodiment, the solvent(s) iii) are chosen from polar protic solvents.

Examples of polar protic solvents include water, lower monohydric alcohols having 1 to 5 carbon atoms such as ethanol and isopropanol, _C2 - _C32 polyols, _C3 and _C4 ketones, and _C2 - _C4 aldehydes.

For the purposes of the present invention, the term “ polyol ” means any organic molecule comprising at least two free hydroxyl groups.

A polyol suitable for the invention may be a compound of alkyl type, linear, branched or cyclic, saturated or unsaturated, bearing on the alkyl chain at least two –OH functions, in particular at least three –OH functions, and more particularly at least four –OH functions.

The 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.

In particular, the polyol may be chosen, for example, from pentaerythritol, trimethylolpropane, caprylyl glycol, glycerol, polyglycerols, such as glycerol oligomers such as diglycerol, polyethylene glycols, and mixtures thereof.

The polyol may also be chosen from glycols having 2 to 8 carbon atoms, in particular ethylene glycol, propylene glycol, 1,3-butylene glycol and dipropylene glycol.

According to a particular embodiment, the solvent(s) iii) are chosen from water, _C1 - _C4 aliphatic alcohols, in particular ethanol, polyols, in particular glycols, and mixtures thereof.

According to a particular embodiment, the composition according to the invention comprises at least one polar protic solvent, and preferably at least water.

According to a particular embodiment, the solvent(s) iii) are chosen from fatty substances, in particular oils.

Examples include volatile oils and non-volatile oils.

" Oil " means a non-aqueous compound, immiscible with water, liquid at room temperature (25°C) and atmospheric pressure (760 mm Hg).

By " immiscible " is meant that the mixture of the same quantity of water and oil, after stirring, does not result in a stable solution comprising only one phase, under the above-mentioned temperature and pressure conditions. The observation is made by eye or by means of a phase contrast microscope if necessary, on 100 g of mixture obtained after sufficient Rayneri stirring to cause a vortex to appear within the mixture (as an indication 200 to 1000 rpm); the resulting mixture being left to stand, in a closed bottle, for 24 hours at room temperature before observation.

The oils may in particular be chosen from volatile or non-volatile hydrocarbon oils, volatile and/or non-volatile silicone oils and/or volatile and/or non-volatile fluorinated oils, and preferably from volatile or non-volatile hydrocarbon oils.

Preferably, the oils are chosen from hydrocarbon oils, preferably non-volatile.

The term " hydrocarbon oil " means an oil containing mainly hydrogen and carbon atoms and possibly one or more functions chosen from hydroxyl, ester, ether and carboxylic functions. A hydrocarbon oil therefore does not contain any silicon or fluorine atoms.

By “ silicone oil ” is meant an oil comprising at least one silicon atom, and in particular at least one Si-O group, and more particularly an organopolysiloxane.

The term “ fluorinated oil ” means an oil comprising at least one fluorine atom.

By " non-polar hydrocarbon oil " is meant a hydrocarbon oil comprising only carbon and hydrogen atoms, preferably non-aromatic (also called hydrocarbon).

By “ polar hydrocarbon oil ” is meant hydrocarbon oils mainly comprising hydrogen and carbon atoms and one or more functions chosen from hydroxyl, ester, ether and carboxylic functions.

According to a particular embodiment, the solvent(s) ii) are or comprise at least one hydrocarbon oil, preferably non-volatile.

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 C ₁₂ -C ₂₂ , carbonates, and mixtures thereof.

According to a preferred embodiment, the hydrocarbon oils are chosen from triglycerides consisting of esters of fatty acids and glycerol, in particular the fatty acids of which may have chain lengths varying from _C4 to _C36 , and in particular from _C18 to _C36 , these oils being able to be linear or branched, saturated or unsaturated. Examples include heptanoic or octanoic triglycerides, caprylic/capric acid triglycerides, vegetable oils such as wheat germ, sunflower, grape seed, sesame, corn, apricot kernel, castor, shea, avocado, olive, soybean, sweet almond, palm, rapeseed, cotton, hazelnut, macadamia, jojoba, alfalfa, poppy, pumpkin, squash, blackcurrant, evening primrose, millet, barley, quinoa, rye, safflower, candlenut, passionflower, musk rose, peanut, coconut, argan, passionflower, kaya, the liquid fraction of shea butter, and the liquid fraction of cocoa butter, as well as mixtures thereof.

According to one embodiment, the non-volatile hydrocarbon oil(s) comprise or consist of at least one non-volatile oil selected from triglycerides consisting of fatty acid esters and glycerol, in particular the fatty acids of which may have chain lengths varying from C ₄ to C ₃₆ , and in particular from C ₈ to C ₃₆ , these oils being able to be linear or branched, saturated or unsaturated as described above, preferably selected from heptanoic or octanoic triglycerides, caprylic/capric acid triglycerides and mixtures thereof and more preferably caprylic/capric acid triglycerides. Caprylic/capric acid triglycerides are in particular available under the reference Palmester 3585 marketed by KLK Oleo.

Examples of volatile hydrocarbon oils include hydrocarbon oils with 8 to 16 carbon atoms.

Non-volatile silicone oils may be chosen in particular from non-volatile polydimethylsiloxanes (PDMS) and phenylated silicones. As volatile silicone oils, examples that may be mentioned are volatile linear or cyclic silicone oils.

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

According to a particular embodiment, the solvent(s) ii) are mixtures of one or more polar protic solvents, in particular chosen from alcohols and/or glycols, and one or more solvents chosen from oils, in particular chosen from volatile or non-volatile oils.

In particular, a composition according to the invention may comprise from 0% to 99.9% by weight, preferably from 0% to 90% by weight, of solvent(s) iii), relative to the total weight of the composition.

Aqueous phase

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

According to a particular embodiment, the composition according to the invention is devoid of aqueous phase.

The composition may comprise water without a water-miscible solvent.

According to another variant, the aqueous phase comprises water and at least one water-miscible solvent.

In the present invention, the term “water-miscible solvent” means a compound which is liquid at room temperature and whose miscibility in water is greater than 50% by weight at 25°C and atmospheric pressure.

The water-miscible solvents that can be used in a composition according to the invention can also be volatile.

Among the water-miscible solvents which may be used in a composition in accordance with the invention, mention may be made in particular of lower monoalcohols having from 1 to 5 carbon atoms such as ethanol and isopropanol, C ₂ -C ₃₂ polyols, C ₃ and C ₄ ketones and C ₂ -C ₄ aldehydes.

For the purposes of the present invention, the term “polyol” means any organic molecule comprising at least two free hydroxyl groups.

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.

The 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.

In particular, the polyol may be chosen, for example, from propylene glycol, pentaerythritol, trimethylolpropane, caprylyl glycol, glycerol, polyglycerols, such as glycerol oligomers such as diglycerol, polyethylene glycols, and mixtures thereof.

According to a particular embodiment, the composition comprises water and is free of water-soluble solvent.

In particular, a composition according to the invention may comprise from 0% to 99.9% by weight, preferably from 0% to 90% by weight, of aqueous phase, relative to the total weight of the composition.

Fat phase

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

According to a particular embodiment, the composition according to the invention is free of fatty phase.

For the purposes of the invention, the term “fatty phase” means a phase comprising at least one fatty substance and all of the liposoluble and lipophilic ingredients used for the formulation of the compositions of the invention.

According to a particular embodiment, the fatty phase comprises at least one oil, in particular a cosmetic oil, as solvent(s) iii) as described above.

The fatty phase may comprise at least a) a hydrocarbon or silicone or fluorinated oil, preferably hydrocarbon, said oil(s) being volatile or non-volatile.

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 C ₁₂ -C ₂₂ , carbonates, and mixtures thereof.

Examples of volatile hydrocarbon oils include hydrocarbon oils with 8 to 16 carbon atoms.

Non-volatile silicone oils may be chosen in particular from non-volatile polydimethylsiloxanes (PDMS) and phenylated silicones. As volatile silicone oils, examples that may be mentioned are volatile linear or cyclic silicone oils.

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

According to one embodiment, the composition according to the invention comprises at least one oil, preferably hydrocarbon-based.

According to a preferred embodiment, the hydrocarbon oils are chosen from triglycerides consisting of fatty acid esters and glycerol, in particular the fatty acids of which may have chain lengths varying from C ₄ to C ₃₆ , and in particular from C ₁₈ to C ₃₆ , these oils being able to be linear or branched, saturated or unsaturated; as examples, mention may in particular be made of heptanoic or octanoic triglycerides, caprylic/capric acid triglycerides; vegetable oils such as wheat germ, sunflower, grape seed, sesame, corn, apricot kernel, castor, shea, avocado, olive, soybean, sweet almond, palm, rapeseed, cottonseed, hazelnut, macadamia, jojoba, alfalfa, poppy, pumpkin, squash, blackcurrant, evening primrose, millet, barley, quinoa, rye, safflower, candlenut, passionflower, musk rose, peanut, coconut, argan, passionflower, kaya; the liquid fraction of shea butter, and the liquid fraction of cocoa butter; as well as mixtures thereof.

According to one embodiment, the non-volatile hydrocarbon oil(s) comprise or consist of at least one non-volatile oil chosen from triglycerides consisting of fatty acid esters and glycerol, in particular the fatty acids of which may have chain lengths varying from _C4 to _C36 , and in particular from _C8 to _C36 , these oils possibly being linear or branched, saturated or unsaturated as described above, preferably chosen from heptanoic or octanoic triglycerides, caprylic/capric acid triglycerides and mixtures thereof and also preferentially caprylic/capric acid triglycerides such as the reference Palmester 3585 marketed by KLK OLEO.

The oily phase may further comprise, mixed with or dissolved in the oil, other fatty substances. Another fatty substance that may be present in the oily phase may be, for example, a wax, a gum, a pasty compound, or mixtures thereof.

The oily phase may further comprise, mixed with or dissolved in the oil, other fatty substances. Another fatty substance that may be present in the oily phase may be, for example, a fatty acid, a wax, a gum, a pasty compound, or mixtures thereof.

The compositions in accordance with the invention may also comprise at least one compound chosen from: a) UV filters distinct from bismuth oxycarbonate particles i), as well as its solvates, such as its hydrates; b) coloring matters; c) cosmetic active agents for the care of keratin materials; d) surfactants distinct from said polymer ii); e) thickeners distinct from said polymer iii); and mixtures thereof.

a) Additional UV filters

The compositions in accordance with the invention may also contain other sunscreens, whether organic or inorganic.

According to a particular embodiment, a composition according to the invention comprises a) at least one complementary UV filter distinct from the bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, required according to the invention and defined above.

By " UV filter distinct from the bismuth oxycarbonate particles " is meant, for the purposes of the present invention, any UV filter whose chemical nature differs from that of the bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, required according to the invention and defined above.

The bismuth oxycarbonate particles, as well as its solvates, such as its hydrates, according to the invention can therefore be used alone or in combination with a) other UV filters, in particular chosen from organic and/or inorganic UV filters.

Thus, the cosmetic composition may also contain one or more complementary UV filters chosen from hydrophilic, lipophilic or insoluble organic UV filters and/or mineral UV filters.

By " hydrophilic UV filter " is meant any organic or inorganic cosmetic or dermatological compound filtering UV radiation capable of being completely dissolved in the molecular state in a liquid aqueous phase or of being in colloidal suspension (for example in micellar form) in a liquid aqueous phase.

By " lipophilic UV filter " is meant any organic or inorganic cosmetic or dermatological compound filtering UV radiation capable of being completely dissolved in the molecular state in a liquid fatty phase or of being in colloidal suspension (for example in micellar form) in a liquid fatty phase.

By " insoluble UV filter " is meant any organic or inorganic cosmetic or dermatological compound filtering UV radiation having a solubility in water of less than 0.5% by weight and a solubility of less than 0.5% by weight in most organic solvents such as paraffin oil, fatty alcohol benzoates and fatty acid triglycerides, for example Miglyol 812 ^® marketed by the company Dynamit Nobel. This solubility, achieved at 70 °C, is defined as the quantity of product in solution in the solvent at equilibrium with an excess of suspended solid after returning to room temperature. It can easily be evaluated in the laboratory.

Complementary organic UV filters are chosen in particular from:

- cinnamic compounds, in particular Ethylhexyl Methoxycinnamate,

- anthranilate compounds, in particular Menthyl anthranilate,

- salicylic compounds, in particular Homosalate and Ethylhexyl Salicylate,

- dibenzoylmethane compounds, in particular Butyl Methoxydibenzoylmethane,

- benzylidene camphor compounds, in particular 3-Benzylidene camphor, 4-Methylbenzylidene camphor, Benzylidene Camphor Sulfonic Acid and Terephthalylidene Dicamphor Sulfonic Acid,

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

- β,β-diphenylacrylate compounds, in particular octocrylene,

- triazine compounds, in particular Phenylene Bis-Diphenyl triazine, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Ethylhexyl Triazone and Diethylhexyl Butamido Triazone,

- benzotriazole compounds, in particular Drometrizole Trisiloxane,

- benzalmalonate compounds, in particular those cited in US patent 5624663, in particular Polysilicone-15,

- benzimidazole derivatives, in particular Phenylbenzimidazole Sulfonic Acid,

- imidazoline compounds, in particular Ethylhexyl Dimethoxybenzylidene Dioxoimidazoline Propionate,

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

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

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

- benzoxazole compounds, as described in patent applications EP 0832642, EP 1027883, EP 1300137 and DE 10162844, in particular 2,4-bis-[5-1(dimethylpropyl)benzoxazol-2-yl-(4-phenyl)-imino]-6-(2-ethylhexyl)-imino-1,3,5-triazine,

- filter polymers and filter silicones, such as those described in particular in application WO 93/04665,

- dimers derived from α-alkylstyrene, such as those described in patent application DE 19855649,

- 4,4-diarylbutadienes compounds, as described in applications EP 0967200, DE 19746654, DE 19755649, EP 1008586, EP 1133980 and EP 0133981, in particular 1,1-dicarboxy(2,2’-dimethyl-propyl)-4,4-diphenylbutadiene, and

- their mixtures.

Inorganic UV filters are generally mineral UV filters, particularly chosen from metal oxides.

The metal oxides can be chosen in particular from titanium, zinc, iron, zirconium and cerium oxides, and their mixtures.

Metal oxide particles can be coated or uncoated.

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 and treated with a silicone, silica, alumina, aluminum stearate and treated with a silicone, silica and treated with a silicone, alumina and treated with a silicone, triethanolamine, stearic acid, sodium hexametaphosphate, or TiO ₂ treated with octyl trimethyl silane, TiO ₂ treated with a polydimethylsiloxane, polydimethylhydrogensiloxane-treated anatase/rutile TiO ₂ , TiO ₂ coated with triethylhexanoin, aluminum stearate and alumina, TiO ₂ coated with aluminum stearate, alumina and silicone, TiO ₂ coated with lauroyl lysine, or TiO ₂ coated with C _9-15 fluoroalcohol phosphate and aluminum hydroxide.

Metal oxides can optionally be doped.

In this respect, we can cite _TiO2 particles doped with at least one transition metal such as iron, zinc, manganese, and more particularly manganese.

The doped particles may be in the form of a dispersion, preferably an oily dispersion. The oil present in the oily dispersion is preferably chosen from triglycerides, including those of capric/caprylic acids. The oily dispersion of titanium oxide particles may additionally comprise one or more dispersing agents, for example a sorbitan ester or a polyoxyalkylenated fatty acid and glycerol ester. More particularly, mention may be made of the oily dispersion of manganese-doped TiO ₂ particles in capric/caprylic acid triglyceride in the presence of tri-PPG-3 myristylether citrate and polyglyceryl-3-polyricinoleate and sorbitan isostearate.

Mention may also be made of 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.

b) Coloring matters

According to a particular embodiment, a composition according to the invention comprises b) at least one coloring material.

Generally speaking, a " coloring material " is intended to designate any compound capable of coloring a composition, that is to say which absorbs in the visible spectrum, in particular so as to appear to the human eye as a color such as yellow, orange, red, violet, blue or green.

Preferably, a composition according to the invention comprises at least one pigment different from the bismuth oxycarbonate particles i) according to the invention, as well as its solvates, such as its hydrates.

By " pigments " is meant white or colored particles, mineral or organic, insoluble in liquid hydrophilic and lipophilic phases, intended to color and/or opacify the composition containing them, said particles being distinct from the particles of bismuth oxycarbonate i), as well as its solvates, such as its hydrates, according to the invention. More particularly, the pigments are slightly or not at all soluble in hydroalcoholic media.

The pigments that can be used are in particular chosen from 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 and ibid, "Pigments, Inorganic, 1. General” 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim10.1002/14356007.a20_243.pub3).

These pigments can be in the form of powder or pigment paste. They can be coated or uncoated.

The pigments can for example be chosen from mineral pigments, organic pigments, lakes, special effect pigments such as mother-of-pearl or glitter, and mixtures thereof.

The pigment may be a mineral pigment. By mineral pigment is meant any pigment that meets the definition of the Ullmann encyclopedia in the inorganic pigment chapter and different from the particles i) according to the invention. Among the mineral pigments useful in the present invention, mention may be made of iron or chromium oxides, manganese violet, ultramarine blue, chromium hydrate, ferric blue and titanium oxide.

The pigment may be an organic pigment.

By organic pigment is meant any pigment that meets the definition of the Ullmann encyclopedia in the organic pigment chapter.

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

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.

According to one embodiment, the composition does not contain Basic Red 51, more preferably does not contain any dye with an imidazolium group, more particularly does not contain any cationic dye with an imidazolium and azo group (azo dye), more particularly does not contain any basic dye (cationic dye).

In one embodiment, the method of the invention and the use of the invention do not use Basic Red 51, more preferably do not use a dye with an imidazolium group, more particularly do not use a cationic dye with an imidazolium and azo group (azo dye), more particularly do not use basic dye (cationic dye).

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.

According to a particular embodiment of the invention, the quantity of pigments distinct from the bismuth oxycarbonate particles i), as well as its solvates, such as its hydrates, according to the invention varies from 0.5% to 40%, and preferably from 1% to 20% relative to the weight of the composition of the invention comprising them.

c) Cosmetic active ingredient

According to a particular embodiment, a composition according to the invention comprises c) at least one cosmetic active ingredient for caring for keratin materials, preferably for caring for the skin.

In particular, the cosmetic active ingredient may be at least one hydrophilic active ingredient and/or one lipophilic active ingredient.

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

Cosmetic active ingredients include, for example, moisturizing agents, depigmenting agents, desquamating agents, humectants, anti-aging agents, mattifying agents, healing agents, antibacterial agents, vitamins and their derivatives or precursors, antioxidant compounds, anti-radical agents, anti-polluting agents, self-tanning agents, anti-glycation agents, soothing agents, deodorant agents, essential oils, NO-synthase inhibitors, agents stimulating the synthesis of dermal or epidermal macromolecules and/or preventing their degradation, agents stimulating the proliferation of fibroblasts, agents stimulating the proliferation of keratinocytes, myorelaxant agents, refreshing agents, tensing agents, depigmenting agents, pro-pigmenting agents, keratolytic agents, slimming agents, agents acting on the energy metabolism of cells, agents insect repellents, antagonists of substances P or CRGP, anti-hair loss agents, and mixtures thereof

The asset(s) may in particular be chosen from:

- 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),

- humectants or moisturizers such as urea, hydroxyureas, glycerol, polyglycerols, glycerolglucoside, diglycerolglucoside, polyglycerylglucosides, xylitylglycoside and plant extracts (in particular tea, mint, orchid, soya, aloe vera, honey, and in particular glycerol;

- C-glycoside compounds, and preferably hydroxypropyl tetrahydropyrantiol (or proxylane);

- antioxidant compounds;

- anti-aging active ingredients, such as hyaluronic acid compounds, and in particular 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;

- keratolytic agents such as lactic acid or glycolic acid; and

- their mixtures.

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.

d) Surfactant

According to a particular embodiment, a composition according to the invention comprises d) at least one surfactant, distinct from the polymer(s) ii) defined previously.

The 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, p. 333-432, 3rd edition, 1979, WILEY, for the definition of the emulsifying properties and functions of surfactants, in particular p. 347-377 of this reference, for anionic, amphoteric and nonionic surfactants.

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 cocamidopropyl betaine, lauramidopropyl betaine and N-carboxyethoxyethyl N-cocoylamidoethyl aminoacetate N-disodium; sultaines, in particular cocoyl amidopropylhydroxy sultaine; and mixtures thereof.

Preferably, this or these surfactants d) have a molar mass of less than 2000.

According to a particular embodiment of the invention, the surfactant(s) d) is (are) chosen from nonionic surfactants.

Among the nonionic surfactants, mention may be made, alone or in mixtures, of a) fatty alcohols, b) alpha-diols, c) alkylphenols, these 3 types of compounds a) to c) being polyethoxylated, polypropoxylated and/or polyglycerolated, and having an aliphatic chain comprising for example 6 to 30 carbon atoms, in particular comprising 10 to 22 carbon atoms, the number of ethylene oxide or propylene oxide groups being able to range in particular from 2 to 200, in particular from 10 to 100 and the number of glycerol groups being able to range in particular from 2 to 200, in particular from 5 to 100, more particularly from 8 to 20 such as 10. Mention may also be made of copolymers of ethylene oxide (EO) and propylene oxide (PO), condensates of ethylene oxide and propylene oxide on alcohols fatty; polyethoxylated fatty amides preferably having from 2 to 30 moles EO, polyglycerolated fatty amides comprising on average 1 to 5 glycerol groups and in particular 1.5 to 4; oxyethylenated sorbitan fatty acid esters having from 2 to 200 moles EO, in particular from 10 to 100 EO; sucrose fatty acid esters, polyethylene glycol fatty acid esters, alkylpolyglycosides, N-alkylglucamine derivatives, amine oxides such as (C ₁₀ -C ₁₄ )alkylamine oxides or N-acylaminopropylmorpholine oxides.

In particular, the surfactant(s) d) may be non-ionic and chosen from those comprising one or more ester groups, one or more hydroxyl groups, and comprising from 10 to 50 carbon atoms, more particularly between 20 and 42 carbon atoms and more than 4 hydroxyl groups, preferably between 10 and 25 hydroxyl groups such as fatty acid and polyglycerol esters such as POLYGLYCERYL-5 LAURATE or polyglyceryl-10-laurate.

The composition according to the invention may also comprise one or more d) anionic surfactants.

As examples of anionic surfactants d) which can be used in the composition according to the invention, mention may be made of alkylcarboxylic acids such as stearic acid, oleic acid and lauric acid. salts of C ₆ -C ₂₄ alkyl monoesters and, alkylcarboxylates, alkyl sulfates, alkyl ether sulfates such as sodium lauryl sulfate, alkyl ester sulfonates or sulfonic acids, alkylamidoether sulfates, alkylarylpolyether sulfates, monoglyceride sulfates, alkylsulfonates, alkylamidesulfonates, alkylarylsulfonates, alpha-olefin sulfonates, paraffin sulfonates, alkylsulfosuccinates such as docusates, alkylethersulfosuccinates, alkylamidesulfosuccinates, alkylsulfoacetates, acylsarcosinates, acylglutamates, alkylsulfosuccinamates, acyl isethionates and N-acyltaurates, salts of alkyl monoesters and of polyglycoside-polycarboxylic acids, salts of alkyl diesters of polyglycoside-polycarboxylic acids, acyllactylates, salts of D-galactoside-uronic acids, salts of alkyl ether-carboxylic acids, salts of alkylaryl ether-carboxylic acids, salts of alkyl amidoether-carboxylic acids, and the corresponding non-salified forms of all these compounds, the alkyl and acyl groups of all these compounds having from 8 to 30 carbon atoms, preferably from 10 to 22 carbon atoms and the aryl group denoting a phenyl group. It is understood that the alkyl groups of the surfactants can be linear or branched, interrupted by one or more heteroatoms or groups chosen from, O, S, N, C(O) or their combination such as ester.

The surfactant(s) d) may be zwitterionic or amphoteric such as betaines. Examples of amphoteric surfactants are in particular chosen from betaines, preferably chosen from alkyl betaines, in particular lauryl betaine; N-alkylamido betaines and their derivatives, in particular cocamidopropyl betaine, lauramidopropyl betaine and N-carboxyethoxyethyl N-cocoylamidoethyl aminoacetate N-disodium; sultaines, in particular cocoyl amidopropylhydroxy sultaine; and mixtures thereof.

The surfactant(s) d) may be cationic.

The cationic surfactants d) may be chosen from alkylimidazolidiniums, such as isostearylethylimidonium ethosulfate, ammonium salts, such as (C12-30 alkyl)-tri(C1-4 alkyl)ammonium halides such as N,N,N-trimethyl-1-docosaminium chloride (or Behentrimonium chloride).

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

According to one embodiment of the invention, when the surfactant(s) d) are a single surfactant, the latter is different from polysorbate 20.

Preferably, the use of the invention, the method of the invention, and the composition of the invention do not use polysorbate 20.

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.

e) Thickener

According to a particular embodiment, a composition according to the invention comprises e) at least one thickener, also sometimes called gelling agent or viscosity modifying agent, distinct from the polymer(s) ii) defined above.

Thickeners can be synthetic, natural or naturally derived, preferably natural or naturally derived.

Such thickeners may more particularly be chosen from natural polymers or polymers of natural origin, in particular of plant origin.

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

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

A composition according to the invention may also comprise at least one adjuvant usual in the cosmetic field chosen from perfumes, pH adjusters (acids or bases), for example citric acid, tartaric acid or oxalic acid, chelating agents, preservatives, softeners, sweeteners, anti-foaming agents, fillers, trace elements, propellants, and mixtures thereof.

Of course, the 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 not substantially, altered by the envisaged addition.

As stated above, a composition according to the invention may be cosmetic, and preferably is cosmetic.

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.

It is preferably a cosmetically acceptable medium, that is to say which has a pleasant color, odor and feel and does not generate unacceptable discomfort, that is to say tingling, tightness, likely to dissuade the user from applying this composition.

Preparation of the compositions

Ingredients (i) and (ii) may be introduced simultaneously or sequentially.

According to a particular embodiment, a solution of polymer ii) is produced in a solvent or a mixture of solvents iii), to which the particles of bismuth oxycarbonate i) are added, as well as its solvates, such as its hydrates.

Thus, according to a particular embodiment, the present invention relates to a process for preparing the compositions as defined above, comprising the steps consisting of:

(a) having a solution of polymer (ii) in a solvent or mixture of solvents (iii); and

(b) bringing together solution (a) with particles of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), 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.

According to a particular embodiment, the polymer(s) ii) optionally in solution in one or more solvents iii) are added to a suspension of bismuth oxycarbonate particles i), as well as its solvates, such as its hydrates, in a solvent or a solvent mixture iii).

When the polymer(s) ii) are added in solution, the solvent(s) iii) of the polymer solution are the same as or different from the solvent(s) iii) of the particle suspension i).

Thus, according to a particular embodiment, the present invention relates to a process for preparing the compositions as defined above, comprising the steps consisting of:

(a) having a dispersion of bismuth oxycarbonate particles of empirical formula (BiO) _{2- x} (CO ₃ ), 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 a solvent or a mixture of solvents iii); and

(b) bringing together a solution of polymer(s) ii), optionally in a solvent or a mixture of solvents iii), with said dispersion (a), said optional solvent(s) of the solution of polymer(s) ii) being identical to or different from said solvent(s) iii) of the dispersion (a).

The pH of the compositions of the invention can be adjusted if necessary by organic or mineral acids or bases.

The pH can be adjusted at any time during the preparation of the compositions of the invention.

A heating step can be carried out at any time during the preparation of the compositions according to the invention.

When the polymer(s) ii) are added in solution in a solvent or solvent mixture iii), the pH of this solvent(s) iii) may be adjusted by one or more organic or mineral acids, or by one or more organic or mineral bases.

Galenic forms of the compositions

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

They can be presented in all classic galenic forms depending on the intended applications and are suitable for topical application, that is to say for application on the surface of the keratin materials considered.

Cosmetic compositions can be presented in the form of an aqueous or hydroalcoholic gel.

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.

They can also be present in anhydrous form, for example in the form of an oil.

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.

Cosmetic compositions can, for example, be used as make-up products.

Cosmetic compositions may, for example, be used as a care and/or sun protection product for the face and/or body of liquid to semi-liquid consistency, and have the appearance of a white or colored cream, more or less creamy, an ointment, a milk, a gel-cream, a lotion, a serum, a paste or a mousse. It may possibly be applied to the skin in the form of an aerosol. It may also be in solid form, for example in the form of a stick.

Cosmetic compositions may be in the form of skin or semi-mucous membrane care products, such as a protective composition, cosmetic care for the face, lips, hands, feet, anatomical folds or body (for example day creams, night creams, day serums, night serums, make-up remover creams, make-up bases, protective or care body milk, after-sun milk, lotion, gel or foam for skin or scalp care, serum, mask or after-shave composition).

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

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

For the purposes of the invention, the term “SPF” (Sun Protection Factor) means: the sun protection factor which measures the level of protection against UV radiation. The SPF value corresponds to the ratio between the minimum time required to obtain a sunburn (erythematogenic) with a sun protection composition and the minimum time without a sun protection composition to obtain said sunburn. 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).

The 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 to be ideal.

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)”.

“UVAPF” means: the index characterizing protection against UVA radiation. In particular, this index could be measured in vivo using the PPD (Persistent Pigment Darkening) method: “PPD” measures the skin color observed 2 to 4 hours after exposure to UVA. This method has been adopted since 1996 by the Japan Cosmetic Industry Association (JCIA) as the official test 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 the effectiveness of UVA protection issued on November 21, 1995 and in force since January 1, 1996). The evaluation of UVA protection can also be measured in vitro with the Labsphere® spectrophotometer. The plate is the material on which the sunscreen composition is applied. For this protocol, polymethyl methacrylate (PMMA) sheets have proven to be ideal. ISO protocol 24443 describes such an in vitro method.

Cosmetic processes and uses

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 keratin materials of a composition according to the invention.

According to yet another of its aspects, the present invention also relates to the non-therapeutic cosmetic use of a composition according to the invention as defined above, for filtering UV radiation, in particular UV-B.

According to yet another of its aspects, the present invention also relates to the non-therapeutic cosmetic use of a composition according to the invention as defined above, to prevent the appearance on the skin, in particular on the face, neckline, arms, hands and/or shoulders, of darker and/or more colored spots giving the skin a heterogeneity of color.

The present invention also relates to a non-therapeutic cosmetic process for limiting the darkening of the skin and/or improving the color and/or uniformity of the complexion comprising the application to the surface of the keratin material of at least one composition according to the invention as defined above.

The present invention further relates to the non-therapeutic cosmetic use of a composition according to the invention as defined above, to prevent premature aging of the skin, in particular the skin of the face, décolleté, arms, hands and/or shoulders.

According to yet another of its aspects, the present invention also relates to the non-therapeutic cosmetic use of a composition according to the invention as defined above, to reduce whitening during the application of said composition.

According to yet another of its aspects, the present invention also relates to the non-therapeutic cosmetic use of a composition according to the invention as defined above, to improve the stability of said composition.

According to yet another of its aspects, the present invention also relates to the non-therapeutic cosmetic use of a composition according to the invention as defined above, to improve the stability with respect to agglomeration and sedimentation of the particles i) within the solvent(s) iii).

It also relates to a non-therapeutic cosmetic process for preventing and/or treating the signs of aging of a keratin material comprising the application to the surface of the keratin material of at least one composition according to the invention as defined above.

According to one of its aspects, the present invention relates to a composition according to the invention as defined above, for its use as agents for the filtration of UV radiation, in particular UV-B.

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

In the description and examples, percentages are weight percentages.

The invention will now be described by means of the following examples given of course as illustrations and not as limitations of the invention.

Example 1: Synthesis of particles ’ bismuth oxycarbonate

Example 1.1: Solvothermal synthesis of crystallized particles 1 with (NH ₄ ) ₂ CO ₃ at 100°C and D - mannitol (0.25 M)

A solution of bismuth nitrate pentahydrate Bi(NO ₃ ) ₃ ·5H ₂ O (0.04 M) and D-mannitol (0.25 M) is prepared in 50 mL of water and stirred until the reagents are completely dissolved.

10 mL of a saturated solution of ammonium carbonate (21 equivalents relative to bismuth) are then added. A white solid precipitates. This mixture is then transferred to a Teflon autoclave reactor and heated for 12 hours at 100 °C.

Product 1 is isolated by centrifugation and washed 5 times alternately with water and ethanol, before being dried in an oven at 60°C.

Product 1 is isolated as a white powder.

Example 1.2: Solvothermal synthesis of crystallized particles 2 with (NH ₄ ) ₂ CO ₃ at 150°C and D - mannitol (2 M)

A solution of bismuth nitrate pentahydrate Bi(NO ₃ ) ₃ ·5H ₂ O (0.40 M) and D-mannitol (2.0 M) is prepared in 800 mL of water and stirred until the reagents are completely dissolved.

160mL of an ammonium carbonate solution (2.1 equivalents relative to bismuth) are then added. A white solid precipitates. After 30 minutes, this mixture is then transferred to a Teflon autoclave type reactor and heated for 12 hours at 150°C.

The product 2 obtained is isolated by centrifugation and washed 3 times with water before being dried in an oven at 60°C.

Product 2 is isolated as a white powder.

Example 2 : Morphology and particle size of ’ bismuth oxycarbonate examples 1.1 and 1.2

The particle morphology for each product prepared according to the protocol of Examples 1.1 or 1.2 was determined by direct observation by 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 dispersion are then placed on an observation grid (copper with carbon surface layer) and dried in ambient air.

The observation was carried out with a Hitachi HT 7700 transmission electron microscope at an accelerating voltage of 100 kV.

Mean dimensions are obtained via particle size measurement by image analysis using ImageJ software ( CA Schneider, WS Rasband, KW Eliceiri, NIH Image to ImageJ: 25 years of image analysis, Nat. Methods. 9 (2012) 671–675 ).

The results are detailed in the following Table 1.

Compound Morphology Average Dimensions (nm) Average length L Average width l Average thickness e Particles i) of example 1.1 Platelets 106 66 41 Particles i) of example 1.2 Platelets 85 52 28

The synthesized bismuth oxycarbonate particles are in the form of platelets. The largest dimension of each particle is less than 400 nm.

Example 3: Preparation of compositions according to the ’ invention A1 to O3

A mother solution of polymer ii), according to Table 2 below, with a mass concentration of 1.0% is prepared in a solvent iii), according to Table 2 below, by stirring until completely solubilized (the temperature and/or pH being possibly adjusted beforehand). The necessary mass of this solution is taken and diluted in the same solvent iii) to reach the desired final concentration.

During the preparation step of the mother solution for composition K1, the pH was adjusted to 4.3 by adding lactic acid.

During the step of preparing the mother solution for composition L, the water/carrageenan mixture was brought to 80°C until completely dissolved and then the mixture was allowed to return to room temperature before the step of adding the particles i) described below.

The bismuth oxycarbonate powder i) prepared previously, according to example 1.1 or 1.2, is then added at a mass concentration of 0.1% in the diluted polymer solution ii) in the solvent iii).

The mixture is homogenized then placed under ultrasound (Prolabo TP 680/DH) at 100% power continuously for 15 minutes, and finally placed under magnetic stirring at 600 revolutions per minute for approximately 24 hours.

The compositions thus obtained, in the form of dispersions, are noted X _n in table 2 below:

Composition according to the invention Bismuth oxycarbonate particles i) Polymer ii) Solvent iii) Mass ratio i) / ii) A1 According to example 1.1 Sodium polymethacrylate ( Darvan 7-N, Mw = 10,000 - 16,000 g/mol, marketed by Vanderbilt ) Water 1 A2 According to example 1.1 Sodium polymethacrylate ( Darvan 7-N, Mw = 10,000 - 16,000 g/mol, marketed by Vanderbilt ) Water 2 A3 According to example 1.1 Sodium polymethacrylate ( Darvan 7-N, Mw = 10,000 - 16,000 g/mol, marketed by Vanderbilt ) Water 100 B1 According to example 1.1 Co-methacrylic acid copolymer of POE PPO OH: Polyether polycarbonate, sodium salt in aqueous solution ( RSY 15007 Cosmetic version, Mw = 75,000 g/mol, marketed by Arkema-Coatex ) Water 1 B2 According to example 1.1 Co-methacrylic acid copolymer of POE PPO OH: Polyether polycarbonate, sodium salt in aqueous solution ( RSY 15007 Cosmetic version, Mw = 75,000 g/mol, marketed by Arkema-Coatex ) Water 2 B3 According to example 1.1 Co-methacrylic acid copolymer of POE PPO OH: Polyether polycarbonate, sodium salt in aqueous solution ( RSY 15007 Cosmetic version, Mw = 75,000 g/mol, marketed by Arkema-Coatex ) Water 20 C1 According to example 1.2 Sodium alginate ( A1112, Mw = 30,000 – 100,000 g/mol, marketed by Sigma-Aldrich ) Water 1 C2 According to example 1.2 Sodium alginate ( A1112, Mw = 30,000 – 100,000 g/mol, marketed by Sigma-Aldrich ) Water 2 C3 According to example 1.2 Sodium alginate ( A1112, Mw = 30,000 – 100,000 g/mol, marketed by Sigma-Aldrich ) Water 20 D1 According to example 1.1 Dextran sulfate ( Dextralip 10C, marketed by Safic-Alcan ) Water 2 D2 According to example 1.1 Dextran sulfate ( Dextralip 10C, marketed by Safic-Alcan ) Water 20 D3 According to example 1.1 Dextran sulfate ( Dextralip 10C, marketed by Safic-Alcan ) Water 100 E1 According to example 1.1 Sodium lignosulfonate ( DP25230, marketed by Borregaard ) Water 1 E2 According to example 1.1 Sodium lignosulfonate ( DP25230, marketed by Borregaard ) Water 2 E3 According to example 1.1 Sodium lignosulfonate ( DP25230, marketed by Borregaard ) Water 100 F1 According to example 1.1 Calcium lignosulfonate ( DP25228, marketed by Borregaard ) Water 1 F2 According to example 1.1 Calcium lignosulfonate ( DP25228, marketed by Borregaard ) Water 2 F3 According to example 1.1 Calcium lignosulfonate ( DP25228, marketed by Borregaard ) Water 100 H1 According to example 1.2 Sodium polystyrene sulfonate ( Reference 243051, Mw = 70000 g/mol, marketed by Sigma Aldrich ) Water 2 H2 According to example 1.2 Sodium polystyrene sulfonate ( Reference 243051, Mw = 70000 g/mol, marketed by Sigma Aldrich ) Water 20 H3 According to example 1.2 Sodium polystyrene sulfonate ( Reference 243051, Mw = 70000 g/mol, marketed by Sigma Aldrich ) Water 100 I1 According to example 1.2 Sodium polystyrene sulfonate ( Reference 434574, Mw = 1000000 g/mol, marketed by Sigma Aldrich ) Water 2 I2 According to example 1.2 Sodium polystyrene sulfonate ( Reference 434574, Mw = 1000000 g/mol, marketed by Sigma Aldrich ) Water 10 I3 According to example 1.2 Sodium polystyrene sulfonate ( Reference 434574, Mw = 1000000 g/mol, marketed by Sigma Aldrich ) Water 100 D1 According to example 1.2 Sodium polyanethole sulfonate ( Part No. 444464, Mw = 9,000 - 11,000 g/mol, marketed by Sigma Aldrich ) Water 2 J2 According to example 1.2 Sodium polyanethole sulfonate ( Part No. 444464, Mw = 9,000 - 11,000 g/mol, marketed by Sigma Aldrich ) Water 20 J3 According to example 1.2 Polyanethole sulfonate Sodium Polyanethole sulfonate ( Part No. 444464, Mw = 9,000 - 11,000 g/mol, marketed by Sigma Aldrich ) Water 100 K1 According to example 1.1 Chitosan (Kiosmetin -CSH, marketed by Kitozyme ) Water 1 K2 According to example 1.1 Chitosan (Kiosmetin -CSH, marketed by Kitozyme ) Water 2 K3 According to example 1.1 Chitosan (Kiosmetin -CSH, marketed by Kitozyme ) Water 100 L According to example 1.1 Carrageenan ( Satiagum VPC 430, marketed by Univar Solutions ) Water 1 M1 According to example 1.1 Modified phosphonate ( ChrysoFluid Optima 100, marketed by Chryso ) Water 1 M2 According to example 1.1 Modified phosphonate ( ChrysoFluid Optima 100, marketed by Chryso ) Water 2 N1 According to example 1.2 Polyethyleneimine ( Reference 408727, Mw = 25,000 g/mol, marketed by Sigma Aldrich ) Water 1 N2 According to example 1.2 Polyethyleneimine ( Reference 408727, Mw = 25,000 g/mol, marketed by Sigma Aldrich ) Water 2 N3 According to example 1.2 Polyethyleneimine ( Reference 408727, Mw = 25,000 g/mol, marketed by Sigma Aldrich ) Water 100 O1 According to example 1.2 Hydrolyzed soy protein Water 1 O2 According to example 1.2 Hydrolyzed soy protein Water 2 O3 According to example 1.2 Hydrolyzed soy protein Water 20

The X _n dispersions thus prepared were characterized by UV/Visible spectrophotometry, by dynamic light scattering, and by analytical centrifugation.

Example 4 : Spectra of ’ absorbances of compositions according to the ’ invention A1 to O3

Each of the dispersions X _n according to example 3 is diluted by adding deionized water so that the final concentration of bismuth oxycarbonate i) is equal to 0.01% by mass, then placed under magnetic stirring at 600 revolutions per minute for 20 min before carrying out the absorbance measurement.

The quartz cell used for the measurements is 1 cm on each side. The absorbance spectra are recorded using a UV-2600 UV-Vis Spectrophotometer (Shimadzu). The baseline determination is carried out beforehand on a quartz cell containing water.

For each composition, the absorbance spectrum obtained is compared to the spectrum of polymer ii) alone, solubilized in water at the same concentration as in the composition in dispersion form.

The absorbance spectra are shown in Figures 1 to 39.

The absorbance spectra show that the compositions according to the invention absorb UV radiation, and in particular UVB (rays with wavelengths between 280 and 320 nm).

The compositions according to the invention are therefore effective for protection against UV radiation, in particular against UVB radiation.

Example 5 : Evaluation of the particle size distribution of compositions A1 to O3

The particle size distribution of the dispersions is determined by dynamic light scattering (DLS) using a ZetaSizer Nano-ZS device (model ZEN3600) marketed by Malvern Panalytical, with the detection angle set at 173°. The technique is particularly suitable for the characterization of submicron-sized objects.

For each of the aqueous dispersions X _n according to example 3, an aliquot is taken and diluted in water until reaching a mass concentration close to 10 ^-4 %. The diluted sample is introduced into a single-use cuvette (DTS0012 from Malvern) and placed in the measuring compartment.

After temperature equilibration for 10 minutes at 25 °C, 6 consecutive measurements are made. The viscosity of water at 25 °C is considered equal to 0.8872 cP.

The CUMULANTS algorithm included in Zetasizer Software 7.13 (Malvern Panalytical) is used for raw data analysis. It allows to determine:
- the “Z-average” parameter, which corresponds to the average hydrodynamic diameter of the objects weighted by the intensity, in other words, it measures the average size of the particles,
- the polydispersity index (PDI) which is associated with the calculation of the Z-average and estimates the width of the size distribution.

The results obtained (Z-average and PDI) for the compositions according to the invention are presented in Table 3 below. The results obtained are averaged over the 6 measurements.

Composition according to the invention Polymer ii) Mass ratio i) / ii) Z-average (nm) PDI
(Polydispersity index) A1 Sodium polymethacrylate 1 154 0.16 A2 Sodium polymethacrylate 2 164 0.17 A3 Sodium polymethacrylate 100 288 0.24 B1 Methacrylic copolymer 1 179 0.22 B2 Methacrylic copolymer 2 162 0.16 B3 Methacrylic copolymer 20 216 0.28 C1 Sodium alginate 1 206 0.19 C2 Sodium alginate 2 220 0.27 C3 Sodium alginate 20 227 0.22 D1 Dextran sulfate 2 172 0.18 D2 Dextran sulfate 20 204 0.23 D3 Dextran sulfate 100 213 0.29 E1 Sodium lignosulfonate 1 145 0.15 E2 Sodium lignosulfonate 2 147 0.14 E3 Sodium lignosulfonate 100 218 0.25 F1 Calcium lignosulfonate 1 152 0.16 F2 Calcium lignosulfonate 2 154 0.15 F3 Calcium lignosulfonate 100 234 0.25 H1 Sodium polystyrene sulfonate 2 210 0.23 H2 Sodium polystyrene sulfonate 20 228 0.27 H3 Sodium polystyrene sulfonate 100 351 0.45 I1 Sodium polystyrene sulfonate 2 243 0.29 I2 Sodium polystyrene sulfonate 10 257 0.35 I3 Sodium polystyrene sulfonate 100 273 0.34 D1 Sodium polyanethole sulfonate 2 195 0.21 J2 Sodium polyanethole sulfonate 20 216 0.26 J3 Sodium polyanethole sulfonate 100 496 0.52 K1 Chitosan 1 494 0.23 K2 Chitosan 2 354 0.22 K3 Chitosan 100 321 0.37 L Carrageenan 1 438 0.46 M1 Modified phosphonate 1 152 0.18 M2 Modified phosphonate 2 162 0.21 N1 Polyethyleneimine 1 222 0.27 N2 Polyethyleneimine 2 230 0.27 N3 Polyethyleneimine 100 214 0.23 O1 Hydrolyzed soy protein 1 180 0.13 O2 Hydrolyzed soy protein 2 188 0.15 O3 Hydrolyzed soy protein 20 231 0.22

The results show that the particles are well dispersed in the compositions according to the invention, and that the average size of the objects is less than 400 nm.

Thus, the results show that the particles form little or no agglomerates within the compositions according to the invention. The compositions according to the invention limit bleaching.

Example 6 : Evaluation of stability by analytical centrifugation compositions A1 to O3

An analytical centrifuge LUMiSizer (model 651) marketed by LUM GmbH is used to analyze the stability of the compositions according to the invention with respect to sedimentation.

The LUMiSizer works by combining centrifugation and STEP (“Space and Time resolved Extinction Profiles”) technology, which consists of measuring the light transmitted over the entire height of the tube containing the sample over time.

The wavelength of the light source is set at 410 nm.

The compositions according to the invention X _n in the form of dispersions and with a mass concentration of bismuth oxycarbonate particles of 0.1% are introduced into polycarbonate tubes with a thickness of 10 mm (reference 110-132xx, LUM GmbH), and centrifuged at a rotation speed of 2000 revolutions per minute (corresponding to an average relative centrifugal acceleration of 520*g) and a temperature of 25°C for 5 minutes.

During the measurement, the transmission profiles along the longitudinal direction of the tubes are recorded every 10 seconds.

The data are analyzed using SEPView 6 software (LUM GmbH).

The amplitude of the sedimentation phenomena involved in the different dispersions is quantified by determining the instability index, the definition of which is given in the technical document: " Instability Index ", T. Detloff, T. Sobisch, D. Lerche, Dispersion Letters Technical, T4 (2013) 1-4, Update 2014. This index is a dimensionless number, between 0 and 1. It is equal to 0 when the sample is stable, i.e. the transmission profiles remain unchanged over time. On the contrary, it is equal to 1 when the particles have completely sedimented.

The instability indices of the compositions according to the invention X _n in the form of dispersions after 5 minutes of centrifugation at 2000 rpm are calculated over the region of interest ranging from longitudinal positions 107 to 125 mm.

The instability index results of the compositions according to the invention are presented in Table 4 below.

Composition according to the invention Polymer ii) Mass ratio i) / ii) Instability index Reference None Not applicable 0.97 A1 Sodium polymethacrylate 1 0.17 A2 Sodium polymethacrylate 2 0.20 A3 Sodium polymethacrylate 100 0.39 B1 Methacrylic copolymer 1 0.23 B2 Methacrylic copolymer 2 0.24 B3 Methacrylic copolymer 20 0.27 C1 Sodium alginate 1 0.16 C2 Sodium alginate 2 0.24 C3 Sodium alginate 20 0.36 D1 Dextran sulfate 2 0.21 D2 Dextran sulfate 20 0.34 D3 Dextran sulfate 100 0.47 E1 Sodium lignosulfonate 1 0.22 E2 Sodium lignosulfonate 2 0.27 E3 Sodium lignosulfonate 100 0.40 F1 Calcium lignosulfonate 1 0.15 F2 Calcium lignosulfonate 2 0.18 F3 Calcium lignosulfonate 100 0.34 H1 Sodium polystyrene sulfonate 2 0.25 H2 Sodium polystyrene sulfonate 20 0.39 H3 Sodium polystyrene sulfonate 100 0.45 I1 Sodium polystyrene sulfonate 2 0.23 I2 Sodium polystyrene sulfonate 10 0.40 I3 Sodium polystyrene sulfonate 100 0.63 D1 Sodium polyanethol sulfonate 2 0.29 J2 Sodium polyanethol sulfonate 20 0.38 J3 Sodium polyanethol sulfonate 100 0.53 K1 Chitosan 1 0.05 K2 Chitosan 2 0.08 K3 Chitosan 100 0.53 L Carrageenan 1 0.03 M1 Modified phosphonate 1 0.18 M2 Modified phosphonate 2 0.18 N1 Polyethyleneimine 1 0.35 N2 Polyethyleneimine 2 0.30 N3 Polyethyleneimine 100 0.36 O1 Hydrolyzed soy protein 1 0.26 O2 Hydrolyzed soy protein 2 0.31 O3 Hydrolyzed soy protein 20 0.40

The instability indices of the compositions according to the invention are significantly lower than that of the bismutite dispersion without polymer, which shows that the presence of the polymer makes it possible to reduce sedimentation phenomena and therefore to improve the stability of the compositions according to the invention.

Example 7 : Preparation of compositions according to the ’ invention P1 to R

The compositions according to the invention P1 to R are prepared according to the protocol detailed in example 3. The solvent iii) being an apolar aprotic solvent, caprylic/capric triglyceride.

The compositions thus obtained, in the form of dispersions, are noted X _n in table 5 below:

Composition according to the invention Bismuth oxycarbonate particles i) Polymer ii) Solvent iii) Mass ratio i) / ii) P1 According to example 1.1 Polyglyceryl-6-polyricinoleate ( SY Glyster CRS-75 MB, marketed by Sakamoto Yakuhin ) Caprylic/Capric Triglyceride 1 P2 According to example 1.1 Polyglyceryl-6-polyricinoleate ( SY Glyster CRS-75 MB, marketed by Sakamoto Yakuhin ) Caprylic/Capric Triglyceride 10 Q1 According to example 1.1 Polyglyceryl-4-diisotearate/polyhydroxystearate/sebacate ( Isolan GPS, marketed by Evonik ) Caprylic/Capric Triglyceride 2 Q2 According to example 1.1 Polyglyceryl-4-diisotearate/polyhydroxystearate/sebacate ( Isolan GPS, marketed by Evonik ) Caprylic/Capric Triglyceride 20 R According to example 1.2 Myristoyl pullulan ( MRP15K05, marketed by Katakura Chikkarin ) Caprylic/Capric Triglyceride 2

The X _n dispersions thus prepared were characterized by UV/Visible spectrophotometry, by dynamic light scattering, and by analytical centrifugation.

Example 8 : Spectra of ’ absorbances of compositions according to the ’ invention P1 to R

Each of the dispersions X _n according to example 7 is diluted by adding caprylic/capric triglyceride so that the final mass concentration of bismuth oxycarbonate particles is equal to 0.01% by mass, then placed under magnetic stirring at 600 revolutions per minute for 20 min before carrying out the absorbance measurement.

The quartz cell used for the measurements is 1 cm on each side. The absorbance spectra are recorded using a UV-2600 UV-Vis Spectrophotometer (Shimadzu). The baseline determination is carried out beforehand on a quartz cell containing caprylic/capric triglyceride.

For each composition, the absorbance spectrum obtained is compared to the spectrum of polymer ii) alone, solubilized in caprylic/capric triglyceride at the same concentration as in the dispersion.

The absorbance spectra show that the compositions according to the invention absorb UV radiation, and in particular UVB (rays with wavelengths between 280 and 320 nm).

The compositions according to the invention are therefore effective for protection against UV radiation, in particular against UVB radiation.

Example 9 : Evaluation of the particle size distribution of compositions P1 to R

The particle size distribution of the dispersions is determined by dynamic light scattering (DLS) using a ZetaSizer Nano-ZS device (model ZEN3600) marketed by Malvern Panalytical, with the detection angle set at 173°. The technique is particularly suitable for the characterization of submicron-sized objects.

For each of the X _n dispersions according to Example 7, an aliquot is taken and diluted in caprylic/capric triglyceride until a mass concentration close to 10 ^-4 % is reached. The diluted sample is introduced into a glass cuvette (model 100-OS, Hellma) and placed in the measuring compartment.

After temperature equilibration for 10 minutes at 25 °C, 6 consecutive measurements are made. The viscosity of caprylic/capric triglyceride at 25 °C is considered equal to 20 cP.

The CUMULANTS algorithm included in Zetasizer Software 7.13 (Malvern Panalytical) is used for raw data analysis. It allows to determine:
- the “Z-average” parameter, which corresponds to the average hydrodynamic diameter of the objects weighted by the intensity, in other words, it measures the average size of the particles,
- the polydispersity index (PDI) which is associated with the calculation of the Z-average and estimates the width of the size distribution.

The results obtained (Z-average and PDI) for the compositions according to the invention are presented in Table 6 below. The results obtained are averaged over the 6 measurements.

Composition according to the invention Polymer ii) Mass ratio i) / ii) Z-average (nm) PDI
(Polydispersity index) P1 Polyglyceryl-6-polyricinoleate 1 117 0.24 P2 Polyglyceryl-6-polyricinoleate 10 243 0.27 Q1 Polyglyceryl-4-diisotearate/polyhydroxystearate/sebacate 2 154 0.21 Q2 Polyglyceryl-4-diisotearate/polyhydroxystearate/sebacate 20 212 0.26 R Myristoyl pullulan 2 130 0.16

The results show that the particles are well dispersed in the compositions according to the invention, and that the average size of the objects is less than 400 nm.

Thus, the results show that the particles form little or no agglomerates within the compositions according to the invention. The compositions according to the invention limit bleaching.

Example 10 : Evaluation of stability by analytical centrifugation compositions P1 to R

An analytical centrifuge LUMiSizer (model 651) marketed by LUM GmbH is used to analyze the stability of the compositions according to the invention with respect to sedimentation.

The LUMiSizer works by combining centrifugation and STEP (Space and Time resolved Extinction Profiles) technology, which consists of measuring the light transmitted over the entire height of the tube containing the sample over time. The wavelength of the light source is set at 410 nm.

The compositions according to the invention X _n in the form of dispersions and with a mass concentration of bismuth oxycarbonate particles of 0.1% are introduced into polyamide tubes with a thickness of 10 mm (reference 110-135xx, LUM GmbH), and centrifuged at a rotation speed of 2000 revolutions per minute (corresponding to an average relative centrifugal acceleration of 520*g) and a temperature of 25°C for 30 minutes.

During the measurement, the transmission profiles along the longitudinal direction of the tubes are recorded every 10 seconds.

The data are analyzed using SEPView 6 software (LUM GmbH).

The amplitude of the sedimentation phenomena involved in the different dispersions is quantified by determining the instability index, the definition of which is given in the technical note: " Instability Index ", T. Detloff, T. Sobisch, D. Lerche, Dispersion Letters Technical, T4 (2013) 1-4, Update 2014. This index is a dimensionless number, between 0 and 1. It is equal to 0 when the sample is stable, i.e. the transmission profiles remain unchanged over time. On the contrary, it is equal to 1 when the particles have completely sedimented.

The instability indices of the compositions according to the invention X _n in the form of dispersions after 30 minutes of centrifugation at 2000 rpm are calculated over the region of interest ranging from longitudinal positions 107 to 125 mm.

The instability index results of the compositions according to the invention are presented in Table 7 below.

Composition according to the invention Polymer ii) Mass ratio i) / ii) Instability index Reference None Not applicable 0.62 P1 Polyglyceryl-6-polyricinoleate 1 0.07 P2 Polyglyceryl-6-polyricinoleate 10 0.13 Q1 Polyglyceryl-4-diisotearate/polyhydroxystearate/sebacate 2 0.10 Q2 Polyglyceryl-4-diisotearate/polyhydroxystearate/sebacate 20 0.34 R Myristoyl pullulan 2 0.05

The instability indices of the compositions according to the invention are significantly lower than that of the bismutite dispersion without polymer, which shows that the presence of the polymer makes it possible to reduce sedimentation phenomena and therefore to improve the stability of the compositions according to the invention.

Claims (19)

Use of:

1. one or more particles of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), 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
2. one or more polymer(s);

the mass ratio R of particle(s) i) / polymer(s) ii) being greater than or equal to 1;
it being understood that:

• when the composition contains polysorbate 20, namely polyoxyethylene sorbitan monolaurate, of formula:

as the only polymer ii), then the mass ratio R of particles i) / polymer(s) ii) is different from 2/0.29; and

• when the composition contains two polymers ii) one of which is polysorbate 20 in a content of 0.3% by mass then the polymer ii) is other than xanthan gum;

for the filtration of UV rays, in particular UV-A and/or UV-B rays, in particular UV-B rays. Use according to claim 1, wherein the bismuth oxycarbonate particles i) are crystallized. Use according to any one of claims 1 or 2, wherein said bismuth oxycarbonate particles i) are of formula (BiO) ₂ (CO ₃ ). Use according to any one of the preceding claims, wherein the largest average dimension of said particles i) is less than or equal to 300 nm. Use according to any one of the preceding claims, in which said particles of bismuth oxycarbonate i), as well as its solvates, such as its hydrates, are in the form of tubes, platelets and/or rods, and in particular:

• when in the form of platelets, the bismuth oxycarbonate particles have 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; 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; 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 with e < l <L;
• when in the form of rods, whether cylindrical or prismatic, the bismuth oxycarbonate particles have 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; an average diameter d ranging from 15 to 150 nm, in particular ranging from 20 to 130 nm, preferably ranging from 25 to 120 nm, more preferably ranging from 25 to 100 nm, and even more preferably ranging from 25 to 60 nm, and with L >d; or
• when in the form of tubes, the bismuth oxycarbonate particles have 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; an average diameter d ranging from 2 to 30 nm, in particular ranging from 3 to 20 nm, and preferably ranging from 5 to 15 nm; and with L > d .

Use according to any one of the preceding claims, wherein said bismuth oxycarbonate particles i), as well as its solvates, such as its hydrates, are present in the composition in a content ranging from 0.01% to 80% by weight, in particular from 0.05% to 75% by weight, preferably from 0.08% to 60% by weight, relative to the total weight of the composition. Use according to any one of the preceding claims, in which the polymer(s) ii) are chosen from:

• lignosulfonic acid, lignosulfonates, polystyrene sulfonics, polystyrene sulfonates, anionic polyanethol derivatives, in particular polyanethol sulfonates, and mixtures thereof,
• alkyl esters or ethers of polyols, in particular glycerol,
• anionic polysaccharides, preferably chosen from sulfated polysaccharides, in particular ulvans, dextran sulfates, carrageenans, and mixtures thereof, and carboxylate polysaccharides, in particular alginates,
• cationic polysaccharides, preferably chosen from polysaccharides with amine groups, in particular chitosans,
• modified polysaccharides, in particular chosen from polysaccharide esters, and preferably from pullulan esters,
• poly(alkylene (C ₂ -C ₅ )imines), and preferably among polyethyleneimines and polypropyleneimines, in particular poly(ethyleneimine),
• polyamino acids, and preferably among proteins,
• anionic acyclic polymers, bearing carboxylic groups or carboxylates of alkali or alkaline earth metals such as sodium, and chosen from homo or copolymers of (meth)acrylic acid, preferably from sodium polymethacrylates and copolymers of (meth)acrylic acid with alkyl (poly)ether (meth)acrylates, in particular copolymers of (meth)acrylic acid and POE/POP (meth)acrylate, and
  - their mixtures.

Use according to any one of the preceding claims, in which the polymer(s) ii) are chosen from:

• lignosulfonates,
• polystyrene sulfonates,
• polyanethol sulfonates,
• alkyl esters or ethers of glycerol,
• dextran sulfates,
• lambda carrageenan,
• naked carrageenan,
• alginates,
• chitosans.
• pullulan esters,
• polyethyleneimines,
• proteins,
• sodium polymethacrylates,
• copolymers of (meth)acrylic acid and POE/POP (meth)acrylate, and
• their mixtures.

Use according to any one of the preceding claims, in which the mass ratio i)/ii) is between 1/1 and 1/0.001, preferably between 1/1 and 1/0.005, more preferably between 1/1 and 1/0.01. Use according to any one of the preceding claims, for the protection of keratin materials, in particular human materials such as skin and/or keratin fibers, in particular human materials such as hair. Composition, preferably cosmetic, comprising:

1. at least one particle of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), 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;
2. at least one polymer;
3. optionally at least one solvent; and
4. optionally at least one compound chosen from: a) UV filters distinct from bismuth oxycarbonate particles i), as well as its solvates, such as its hydrates; b) coloring matters; c) cosmetic active ingredients for the care of keratin materials; d) surfactants distinct from said polymer ii); e) thickeners distinct from said polymer ii); and mixtures thereof; and

it being understood that:

• the mass ratio R of particle(s) i) / polymer(s) ii) is greater than or equal to 1, preferably R is greater than 1;
• where ii) the polymer is polyvinylpyrrolidone (PVP) then said composition does not contain oleic acid; and
• when the composition contains polyoxyethylene sorbitan monolaurate as the sole polymer ii), then the mass ratio particles i) / polymer(s) ii) is different from 2/0.29; and
• when the composition contains two polymers ii) one of which is polysorbate 20 in a content of 0.3% by mass then polymer ii) is other than xanthan gum.

Composition according to the preceding claim, in which i) the particle(s) of bismuth oxycarbonate is (are) present in the composition, in a content ranging from 0.01% to 80% by weight, in particular from 0.05% to 75% by weight, preferably from 0.08% to 60% by weight, relative to the total weight of the composition. Composition according to any one of claims 11 or 12, comprising a single solvent iii). Composition according to any one of claims 11 to 13, in which the solvent(s) iii) are chosen from polar protic solvents, in particular from water, C ₁ -C ₄ aliphatic alcohols, in particular ethanol, polyols, in particular glycols, and mixtures thereof, and preferably at least water. Composition according to any one of claims 11 to 13, in which the solvent(s) iii) are chosen from oils, in particular from hydrocarbon oils, preferably non-volatile. Composition according to the preceding claim, in which the solvent(s) iii) are chosen from triglycerides consisting of esters of fatty acids and glycerol, in particular the fatty acids of which may have chain lengths varying from C ₄ to C ₃₆ , and in particular from C ₈ to C ₃₆ , preferably chosen from heptanoic or octanoic triglycerides, caprylic/capric acid triglycerides and mixtures thereof and more preferably caprylic/capric acid triglycerides. Cosmetic process for treating keratin materials, in particular human materials, such as skin and/or keratin fibres, in particular human materials, such as hair, comprising at least the application to the keratin materials of i) at least one particle of bismuth oxycarbonate of empirical formula (BiO) _{2- x} (CO ₃ ), 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 ii) of at least one polymer, and it being understood that the mass ratio R particle(s) i)/polymer(s) ii) is greater than or equal to 1, preferably R is greater than 1. Cosmetic process according to the preceding claim, comprising the application to keratin materials, in particular human materials such as the skin and/or keratin fibers, in particular human materials such as the hair, of at least one cosmetic composition as defined in any one of claims 11 to 16. Method according to claim 17 or 18 for filtering UV radiation, in particular UV-B, in particular for the protection of keratin materials, in particular human, in particular skin and/or keratin fibers, in particular human, such as hair.