WO2002039972A1 - Insoluble organic uv filters and cosmetic use thereof - Google Patents

Abstract

The invention concerns insoluble organic compounds containing one or several benzazole and/or benzothiofen, benzofuran or indole groups, filtering UV radiation, in the form of fine particles having a mean size ranging between 10 nm and 5 mu m, and their use for protecting the skin, the hair and materials sensitive to UV radiation. Said compounds can be obtained by a method which consists in grinding rough particles in the presence of one or several suitable surfactants.

Description

 Insoluble organic UV filters and their use in cosmetics

The present invention relates to insoluble organic compounds filtering UN radiation, cosmetic compositions containing them as well as their use as agents screening UN radiation to protect materials sensitive to UN radiation, skin, hair or to control color. skin.

We know that light radiation with wavelengths between 280 nm and 400 nm allows the browning of the human epidemic and that rays with wavelengths between 280 and 320 nm, known under the name of UN- B, cause erythema and skin burns which can affect the development of natural tanning. For these reasons, as well as for aesthetic reasons, there is a constant demand for means of controlling this natural tan in order to thereby control the color of the skin. It is therefore advisable to filter this radiation UN-B.

It is also known that the UN-A rays, of wavelengths between 320 nm and 400 nm, which cause browning of the skin, are capable of inducing an alteration of the latter, in particular in the case of a sensitive skin or skin continuously exposed to solar radiation. The UN-A rays cause in particular a loss of elasticity of the skin and the appearance of wrinkles leading to premature aging. They promote the triggering of the erythematous reaction or amplify this reaction in certain subjects and can even be the cause of phototoxic or photoallergic reactions. Thus, for aesthetic and cosmetic reasons such as the conservation of the natural elasticity of the skin for example, more and more people wish to control the effect of the UNA rays on their skin. It is therefore desirable to also filter UN-A radiation.

A large number of compounds have already been proposed as sunscreens, mainly in the form of soluble organic filters or insoluble mineral compounds. These filters must be able to absorb or block the harmful rays of the sun while remaining harmless to the user.

In this regard, and in order to limit the possible risks of skin allergy associated with the use of soluble organic filters, more and more insoluble mineral compounds have been used for some time such as zinc oxide or titanium oxide. However, these mineral compounds can have the disadvantage of being sensitive to solar radiation. Furthermore, in equivalent quantities, these mineral compounds are less effective in UN protection than organic filters.

A number of organic compounds with benzazole and / or benzofuranyl groups have already been proposed as sunscreens. Examples that may be mentioned include the 2-phenylbenzoxazoles, benzothiazoles and benzimidazoles described in the patents DE 676 103 and CH 350 763, the 2-arylbenzimidazoles described in patent US Pat. No. 5,501,850, the benzimidazolylbenzazoles Ν- substituted for patent US 5 961,960, the benzazole derivatives described in patent application EP A-0 669 323 or the benzofuranylbenzoxazoles of US patent 5,518,713, the bis-benzimidazole derivatives described in US patent 2,463,264 and in J. Am. Chem . Soc, 79, 5706-5708, 1957, the bis-benzoxazole derivatives described in J. Am. Chem. Soc, 82, 609 - 611, 1960, the silicon benzazole compounds described in patent application EP-A-0 921 126 or the silicon benzimidazole derivatives of patent application EP-A-0 712 855. None of these However, documents do not mention the use of these filters in the form of very small insoluble particles, that is to say a size of the order of a micron or less than a micron.

Also known from documents WO 95/22959 and WO 97/03643 are insoluble organic UV filters of the oxalanilide, triazine, triazole, vinyl amide, cinnamamide and benzimidazole sulfonic type in the form of particles of average size between 0.01 and 2 μm.

Some of these filters, in particular the sulfonic benzimidazole derivatives, exhibit variations in solubility at high temperature which lead to significant recrystallization in the support. Such a phenomenon can occur result in a loss of effectiveness of the filters and a deterioration in the cosmetic properties of the compositions containing them.

The Applicant, following significant research in the field of photoprotection, has discovered new insoluble organic compounds containing one or more benzazole and / or benzofuran, beήzothiofen or indole groups capable of absorbing both in the UN-A and in UN-B, in the form of fine particles of average size between 10 nm and 5 μm, which allow effective protection of the skin, the lips or the hair as well as other photosensitive materials against the unfavorable effects UV radiation.

As used in the present invention, the term benzazole includes both benzothiazoles, benzoxazoles and benzimidazoles.

By insoluble compound is meant, within the meaning of the present invention, a compound having a solubility in water of less than 0.1% by weight and a solubility of less than 1% by weight in most organic solvents such as paraffin, fatty alcohol benzoates and fatty acid triglycerides, for example Miglyol ^® 812 sold by the company

DYΝAMIT NOBEL. This solubility, defined at 70 ° C as the amount of product in solution in the solvent at equilibrium with an excess of solid in suspension, can easily be evaluated in the laboratory.

These insoluble organic compounds make it possible to overcome the drawbacks of the soluble organic filters and the insoluble mineral filters of the prior art. These materials are more effective sun filters than the mineral filters of the prior art, since they combine two filtering mechanisms, namely the absorption of UV radiation by organic chromophores and the dispersion-reflection of light by particle surfaces. They are therefore entirely suitable for the preparation of cosmetic compositions intended for the protection of the skin and the hair against solar radiation. In addition, in addition to their filtering and dispersing properties, the insoluble organic compounds according to the invention have good chemical and photochemical stability. The present invention therefore relates to insoluble organic compounds filtering the UV radiation corresponding to one of the formulas (I), (II) and (III) below and which are in the form of particles having an average size comprised between 10 nm and 5 μm.

The subject of the invention is also cosmetic compositions containing at least one insoluble organic compound of formula (I), (II) or (III), having an average size of between 10 nm and 5 μm.

A subject of the invention is also the use of these insoluble compounds as agents for screening out UV-A and UV-B radiation, for example for the protection of materials sensitive to UV radiation, in particular to solar radiation, for controlling the color of the skin or for the preparation of drugs intended to prevent the harmful effects of UV-A and UV-B radiation.

The insoluble organic compounds filtering UV radiation having an average size of between 10 nm and 5 μm are chosen from those corresponding to one of the following formulas (I), (II) and (III):

dans lesquelles chacun des symboles Y représente indépendamment un atome d'oxygène ou de soufre ou un groupe NR₂, chacun des symboles Z représente indépendamment un atome d'azote ou un groupe CH, chacun des symboles Ri représente indépendamment un groupe OH, un atome d'halogène, un groupe alkyle en Cι.g, linéaire ou ramifié, contenant éventuellement un atome de silicium, ou un groupe alcoxy en -s, linéaire ou ramifié, chacun des nombres m vaut indépendamment 0, 1 ou 2, n représente un nombre entier compris entre 1 et 4 inclus, p est égal à 0 ou 1, chacun des nombres q est égal indépendamment à 0 ou 1, chacun des symboles R₂ représente indépendamment un atome d'hydrogène, un groupe benzyle ou alkyle en Cι.₈, linéaire ou ramifié, contenant éventuellement un atome de silicium,

in which each of the symbols Y independently represents an oxygen or sulfur atom or a group NR ₂ , each of the symbols Z independently represents a nitrogen atom or a group CH, each of the symbols Ri independently represents an OH group, an atom of halogen, a Cι.g alkyl group, linear or branched, optionally containing a silicon atom, or a -s alkoxy group, linear or branched, each of the numbers m is independently 0, 1 or 2, n represents a whole number between 1 and 4 inclusive, p is equal to 0 or 1, each of the numbers q is independently equal to 0 or 1, each of the symbols R ₂ independently represents a hydrogen atom, a benzyl or Cι alkyl group. ₈ , linear or branched, optionally containing a silicon atom,

A represents a radical of valence n chosen from those of formulas

(b) (c) () (e)

⁽ 0 (j) (k) (D

(m) (n) (o)

in which each of the symbols R ₃ independently represents a halogen atom or a C or alkoxy, linear or branched, or hydroxy group,

R represents a hydrogen atom or a linear or branched Cμ alkyl group, c = 0 - 4, d = 0 - 3, e = 0 or 1, and f = 0 - 2.

As examples of preferred compounds of formula (I) from the family of 2-arylbenzazoles, mention may be made of 2-benzoxazol-2-yl-4-methylphenol, 2- (1H-benzimidazol-2-yl) - 4-methoxyphenol or 2-benzothiazol-2-ylphenol, these compounds being able to be prepared for example according to the methods described in patent CH 350 763. As examples of preferred compounds of formula (I) of the family of benzimidazolylbenzazoles, mention will be made of 2,2'-bis-benzimidazole, 5.5 ', 6,6'- tetramethyl-2,2'-bis -benzimidazole, 5,5'-dimethyl-2,2'-bis-benzimidazoIe, 6-methoxy-2,2'-bis-benzimidazole, 2- (1H-benzimidazol-2-yl) ~ benzothiazole, 2- (1H-benzimidazol-2-yl) -benzoxazole and N, N'-dimethyl ~

2,2'-bis-benzimidazole, these compounds can be prepared according to the procedures described in US Patents 5,961,960 and US 2,463,264.

As examples of preferred compounds of formula (I) from the phenylene-benzazole family, mention will be made of 1,4-phenylene-bis- (2-benzoxazolyl), 1,4-phenylene-bis- (2- benzimidazolyle), 1,3-phenylene-bis- (2-benzoxazolyle), 1,2-phenylene-bis- (2-benzoxazolyle), 1,2-phenylene-bis- (benzimidazolyl), 1,4 -phenylene-bis- (N-2-ethylhexyl-2-benzimidazolyl) and 1,4-phenylene-bis- (N-trimethylsilylmethyl-2-benzimidazolyl), these compounds can be prepared according to the procedures described in the US patent 2,463,264 and in the publications J. Am.Chem. Soc, 82, 609

(1960) and J. Am. Chem. Soc, 79, 5706-5708 (1957).

As examples of preferred compounds of formula (I) of the family of benzofuranyl-benzoxazoles, mention may be made of 2- (2-benzofuranyl) -benzoxazole, 2- (benzofuranyl) -5-methylbenzoxazole and 2- (3 -methyl-2-benzofuranyl) - benzoxazole, these compounds can be prepared according to the procedures described in US Pat. No. 5,518,713.

As preferred compounds of formula (II), there may be mentioned, for example, 2,6-diphenyl-1,7-dihydro-benzo [1,2-d; 4,5-d '] - di-imidazole corresponding to the formula

or 2,6-distyryl-1,7-dihydro-benzo [1,2-d; 4,5-d '] - di-imidazole or 2,6-di (p-tert-butylstyryl) -1,7-dihydrobenzo [1,2-d; 4,5-d '] - di-imidazole, which can be prepared according to application EP 0 669 323. As preferred compound of formula (III), mention may be made of 5,5'-bis- [(2-phenyl) -benzimidazole] of formula:

H H whose preparation is described in J. Chim. Phys., 64, 1602 (1967).

Among these insoluble organic compounds filtering UV radiation, very particularly preferred is 2- (1H-benzimidazol-2-yl) benzoxazole, 6-methoxy-2,2'-bis-benzimidazole, 2- (1H-benzimidazol- 2-yl) -benzothiazole, 1,4-phenylene-bis- (2-benzoxazolyl) 1,4-phenylene-bis- (2-benzimidazolyl) 1,3-phenylene-bis- (2-benzoxazolyl ), 1,2-phenylene-bis- (2-benzoxazolyl), 1,2-phenylene-bis- (2-benzimidazolyle) and 1,4- phenylene-bis- (N-trimethylsilylmethyl-2-benzimidazoyl) .

As indicated above, the average size of the insoluble particles of the organic compounds described above is between 10 nm and 5 μm.

The particles preferably have an average size of between 10 nm and 2 μm, and more preferably between 20 nm and 2 μm.

The average particle size can be determined by any conventional method such as optical methods (quasi-elastic diffusion or laser diffusion), methods by centrifugation or methods of microscopic visualization and image analysis.

The insoluble organic filters according to the invention can be brought in the particulate form having the desired average size by any suitable means, such as dry grinding or in solvent medium, sieving, atomization, micronization or spraying. The insoluble organic filters according to the invention can in particular be obtained by a process for grinding coarse particles into presence of one or more suitable surfactants making it possible to improve the dispersion of the particles thus obtained in cosmetic formulations.

An example of a method for reducing the size of particles of insoluble organic filters is described in documents WO 95/22959 and

WO 97/03643. The grinding apparatus used according to these documents can be a jet, ball, vibration or hammer mill and preferably a high agitation mill or an impact mill and more particularly a rotary ball mill, a vibrating crusher, a tube crusher or a rod crusher.

The insoluble organic compounds filtering UV can be used in cosmetic compositions, in particular compositions protecting the human epidermis or the hair, anti-sun compositions or make-up products.

These cosmetic compositions generally contain from 0.1 to 15% by weight, preferably from 0.2 to 10% by weight, relative to the total weight of the cosmetic composition, of insoluble organic compounds filtering UV radiation.

The cosmetic, and in particular anti-sun, compositions of the present invention may also contain one or more additional organic sun filters, active in the UV-A and / or UV-B field, different from the insoluble filters described above. . These sunscreens can in particular be chosen from cinnamic derivatives, dibenzoylmethane derivatives, salicylic derivatives, benzylidenecamphor derivatives, triazine derivatives such as those described in patents or patent applications US 4367 390, EP 0 863 145, EP 0 517 104, EP 0 570 838, EP 0 796 851, EP 0 775 698, EP 0 878 469, EP 0 933 376 and EP 0 893 119, benzophenone derivatives, β, β'-diphenylacrylate derivatives , phenylbenzimidazole derivatives, anthranilic derivatives, imidazoline derivatives, methylene-bis- derivatives (hydroxyphenylbenzotriazole) such as those described in patents or patent applications US 5,237,071, US 5,166,355, GB 2,303 549, DE 19726184 and EP 0 893 119, derivatives of p-aminobenzoic acid, screening hydrocarbon polymers and screening silicones such as those described in particular in application WO 93/04665.

There may be mentioned as examples of such additional sunscreens active in UV-A and / or UN-B, the following compounds designated by their name IΝCI, as well as their mixtures:

para-aminobenzoic acid derivatives: - PABA - Ethyl PABA

- Ethyl Dihydroxypropyl PABA

- Ethylhexyl Dimethyl PABA sold in particular under the trade name ESCALOL 507 by ISP, - Glyceryl PABA,

- PEG-25 PABA sold under the trade name UVTΝUL P25 by BASF,

salicylic derivatives:

- Homosalate sold under the trade name EUSOLEX HMS by ROΝA / EM INDUSTRIES,

- Ethylhexyl Salicylate sold under the trade name NEO HELIOPAN OS by HAARMANN ET REIMER,

- Dipropyleneglycol Salicylate sold under the trade name DIPSAL by SCHER, - TEA Salicylate sold under the trade name NEO HELIOPAN TS by

HAARMANN AND REIMER,

dibenzoylmethane derivatives:

- Butyl Methoxydibenzoylmethane sold in particular under the trade name PARSOL 1789 by HOFFMANN LAROCHE,

- Isopropyl Dibenzoylmethane, cinnamic derivatives:

- Ethylhexyl Methoxycinnamate sold in particular under the trade name PARSOL MCX by HOFFMANN LAROCHE,

- Isopropyl Methoxycinnamate - Isoamyl Methoxycinnamate sold under the trade name NEO

HELIOPAN E 1000 by HAARMANN AND REIMER,

- Cinoxate,

- DEA Methoxycinnamate,

- Diisopropyl Methylcinnamate, - Glyceryl Ethylhexanoate Dimethoxycinnamate

β.β-diphenylacrylate derivatives:

- Octocrylene sold in particular under the trade name UVINUL-539 by BASF, - Etocrylene sold in particular under the trade name UVINUL N-35 by

BASF

benzophenone derivatives:

- Benzophenone-1 sold under the trade name UVINUL 400 by BASF, - Benzophenone-2 sold under the trade name UVINUL D-50 by

BASF

- Benzophenone-3 or Oxybenzone sold under the trade name UVINUL M-40 by BASF,

- Benzophenone-4 sold under the trade name UVINUL MS-40 by BASF,

- Benzophenone-5,

- Benzophenone-6 sold under the trade name HELISORB 11 by NORQUAY,

- Benzophenone-8 sold under the trade name SPECTRA-SORB UV- 24 by AMERICAN CYANAMID

- Benzophenone-9 sold under the trade name UVINUL DS-49 by BASF,

- Benzophenone- 12 benzylidene camphor derivatives:

- 3-Benzylidene Camphor manufactured under the name MEXORYL SD by CHIMEX,

- 4-Methylbenzylidene Camphor sold in particular under the trade name EUSOLEX 6300 by MERCK,

- Benzylidene Camphor Sulfonic Acid manufactured under the name MEXORYL SL by CHIMEX,

- Camphor Benzalkonium Methosulfate produced under the name MEXORYL SO by CHIMEX, - Terephthalylidene Dicamphor Sulfonic Acid produced under the name

MEXORYL SX by CHIMEX,

- Polyacrylamidomethyl Benzylidene Camphor manufactured under the name MEXORYL S W by CHIMEX,

phenylbenzimidazole derivatives:

- Phenylbenzimidazole Sulfonic Acid sold in particular under the trade name EUSOLEX 232 by MERCK

- Benzimidazilate sold under the trade name NEO HELIOPAN AP by HAARMANN ET REIMER

triazine derivatives:

- Anisotriazine sold under the trade name TLNOSORB S by CIBA GEIGY

- Ethylhexyl triazone sold in particular under the trade name UVINUL T150 by BASF,

- Diethylhexyl Butamido Triazone with the trade name UVASORB HEB by SIGMA 3V,

phenylbenzotriazole derivatives: - Drometrizole Trisiloxane sold under the trade name SILATRIZOLE by RHODIA CHIMIE,

- Methylene bis-Benzotriazolyl Tetramethylbutylphenol sold in solid form under the trade name MIXXIM BB / 100 by FAIRMOUNT CHEMICAL or in micronized form in aqueous dispersion under the trade name TINOSORB M by CIB A SPECIALTY CHEMICALS,

anthranilic derivatives: - Menthyl Anthranilate sold under the trade name NEO HELIOPAN

MA by HAARMAN AND REIMER,

imidazoline derivatives:

- Ethylhexyl Dimethoxybenzylidene Dioxoimidazoline Propionate

benzalmalonate derivatives:

- Benzalmalonate-functional polyorganosiloxane sold under the trade name PARSOL SLX by HOFFMANN LAROCHE

The more particularly preferred organic UV filters are chosen from the following compounds:

- Ethylhexyl Salicylate,

- Butyl Methoxydibenzoylmethane,

- Ethylhexyl Methoxycinnamate, - Octocrylene,

- Phenylbenzimidazole Sulfonic Acid,

- Terephthalylidene Dicamphor Sulfonic Acid,

- Benzophenone-3,

- Benzophenone-4, - Benzophenone-5,

- 4-Methylbenzylidene Camphor,

- Benzimidazilate,

- Anisotriazine,

- Ethylhexyl Triazone, - Diethylhexyl Butamido Triazone,

- Methylene bis-Benzotriazolyl Tetramethylbutylphenol,

- Drometrizole Trisiloxane, and their mixtures. The cosmetic compositions according to the invention may also contain agents for artificial tanning and / or browning of the skin (self-tanning agents) such as dihydroxy acetone (DH A).

The cosmetic compositions according to the invention may also contain one or more mineral pigments and in particular nanopigments of metal oxides, coated or not, such as for example titanium oxide nanopigments in amorphous or crystallized form (rutile and / or anatase), iron oxide, zinc oxide, zirconium oxide or cerium oxide. These nanopigments have an average particle size of between 5 nm and

100 nm, preferably between 10 nm and 50 nm and are all known UV photoprotective agents.

These nanopigments can be coated with known coating agents such as, for example, alumina and / or aluminum stearate. Such coated or uncoated nanopigments are described, for example, in patent applications EP-A-0 518 772 and EP-A-0 518 773.

The cosmetic compositions may also contain usual adjuvants of formulation such as fatty substances, physiologically acceptable organic solvents, silicones, surfactants, anionic, cationic, nonionic, amphoteric polymers or their mixtures, thickening agents, antioxidants, clouding agents, stabilizers, defoamers, fragrances, preservatives, fillers, sequestering agents, propellants, pH adjusting agents, dyes and mixtures thereof.

They can also contain one or more cosmetic active ingredients chosen, for example, from softening agents, hydroxy acids, vitamins, hydrating agents, emollient agents, anti-free radical agents, substance P antagonists, anti-inflammatory agents. and mixtures of these compounds.

The fatty substances can be constituted by an oil or a wax or their mixtures, and they also include fatty acids, fatty alcohols and fatty acid esters. The oils can be chosen from animal, vegetable, mineral or synthetic oils and in particular from petrolatum, paraffin oil, silicone oils, volatile or not, isoparaffins, polyolefins, fluorinated and perfluorinated oils. Likewise, the waxes can be chosen from animal, fossil, vegetable, mineral or synthetic waxes known per se. Among the organic solvents, mention may be made of lower alcohols and polyols such as ethanol, isopropanol, propylene glycol, glycerin and sorbitol.

The thickeners may be chosen in particular from guar gums and celluloses, modified or not, such as hydroxypropylated guar gum, methylhydroxyethylcellulose, hydroxypropylmethylcellulose or also hydroxyethylcellulose.

Of course, a person skilled in the art will take care to choose this or these optional additional compounds and / or their quantities so that the advantageous properties intrinsic to the invention, and in particular the insolubility of the agents screening out UV radiation, are not not altered by the planned addition (s).

The compositions of the invention can be prepared according to techniques well known to those skilled in the art, in particular those intended for the preparation of emulsions of the oil-in-water or water-in-oil type.

This composition can be in particular in the form of an emulsion, simple or complex (O / W, W / O, HE / O or W / O / W) such as a cream, a milk, a gel or a gel- cream, powder or solid stick, and can optionally be packaged as an aerosol and come in the form of a foam or spray.

When it is an emulsion, the aqueous phase thereof may comprise a nonionic vesicular dispersion prepared according to known methods (Bangham, Standish and Watkins, J. Mol. Biol. 13, 238 (1965), FR 2 315 991 and FR 2 416 008).

The cosmetic composition of the invention can be used as a composition for protecting the human epidermis or the hair against ultraviolet rays, as an anti-sun composition or as a make-up product. When the cosmetic composition according to the invention is used for the protection of the human epidemic against UV rays, or as an antisun composition, it may be in the form of a suspension or of dispersion in solvents or fatty substances, in the form of nonionic vesicular dispersion or alternatively in the form of an emulsion, preferably of the oil-in-water type, such as a cream or a milk, in the form of an ointment, gel, cream gel, solid stick, stick, powder, aerosol foam or spray.

When the cosmetic composition according to the invention is used for protecting the hair against UV rays, it can be in the form of a shampoo, lotion, gel, emulsion, nonionic vesicular dispersion and constitute, for example, a composition to rinse, apply before or after shampooing, before or after coloring or discoloration, before, during or after permanent or straightening, a styling or treating lotion or gel, a brushing lotion or gel. or styling, a composition of permanent or straightening, coloring or bleaching of the hair.

When the composition is used as a makeup product for the eyelashes, the eyebrows or the skin, such as an epidermis treatment cream, a foundation of lipstick, a lipstick stick, eyeshadow, blush, mascara or liner also called "eyeliner", it can be in solid or pasty, anhydrous or aqueous form, such as oil-in-water or water-in-oil emulsions, nonionic vesicular dispersions or suspensions. As an indication, for the anti-sun formulations in accordance with the invention, which have an oil-in-water emulsion type support, the aqueous phase generally represents from 50 to 95% by weight, preferably from 70 to 90% by weight. weight, relative to the entire formulation, the oily phase of 5 to 50% by weight, preferably 10 to 30% by weight, relative to the entire formulation, and the (co) emulsifier (s) from 0.5 to

20% by weight, preferably from 2 to 10% by weight, relative to the whole of the formulation. The insoluble filtering agents of the present invention can also be used to protect materials, such as organic or mineral glasses or plastics, sensitive to radiation.

UV, especially solar radiation. The particles are then applied to or incorporated into the material to be protected in an effective amount.

The subject of the invention is also a non-therapeutic process for protecting the skin and / or the hair against ultraviolet radiation, in particular solar radiation, which consists in applying to the skin or the hair an effective amount of the cosmetic composition. defined above, or of a compound of formula (I), (II) or (III) as defined above.

The invention finally relates to a non-therapeutic process for controlling the variation in skin color due to UV radiation, which consists in applying to the skin an effective amount of the cosmetic composition defined above, or of a compound of formula (I), (II) or (III) as defined above.

The following examples illustrate the invention.

Examples of compounds

Example 1

Synthesis of 1,4-phenylene-bis- (2-benzoxazolyl)

A heterogeneous mixture is heated consisting of 50 g (0.3 mole) of terephthalic acid, 131 g (1.2 moles) of 2-aminophenol, 1.2 g of boric acid and 360 g of acid polyphosphoric, for 4 hours under a nitrogen atmosphere and stirring at a temperature between 190 and

205 ° C. After cooling to about 100 ° C, the mixture is poured into 2.5 liters of ice water. The precipitate is collected by filtration, washed with a 5% aqueous sodium carbonate solution until the washing water is at basic pH, then with water until the washing water has a pH close to neutral. After recrystallization of the solid obtained from N-methylpyrrolidone and drying, 76.1 g of 1,4-phenylene-bis- (2-benzoxazolyl) are obtained (yield 81%) in the form of a pale yellow powder.

Elementary analysis for C ₂₀ H ₁₂ N ₂ O ₂ : calculated: C 76.91; H 3.87; N 8.97 found: C 76.50; H 3.98; N 8.99

Preparation of an aqueous dispersion of the filter:

Small fractions of the insoluble filter obtained in the form of powder are introduced into a mixture, previously homogenized, of water and 7.5% of the mixture, with moderate stirring using a stirrer equipped with a deflocculator. alkylpolyglucoside marketed under the name

PLANTAREN ^® by the company HENKEL. The mixture is left stirring for 45 minutes, taking care not to introduce air into the suspension.

Grinding: The predispersion obtained by pumping is introduced into the bowl

(capacity 150 ml) of a Dyno-Mill type ball mill marketed by the company WAB, filled up to 80% of its capacity with glass beads of 1 mm in diameter. Grinding is carried out in a closed circuit for 2 hours 30 minutes with circulation of water to avoid overheating of the preparation. The dispersion obtained is stabilized using xanthan gum. The grinding can also be carried out with circulation of the dispersion continuously during the entire grinding time.

The average diameter of the number distribution for the sample thus obtained, determined using a Mastersizer 2000 device from the company

MALVERN, is 0.450 μm. The particle size profile is shown in Figure 1 of the accompanying drawing. Example 2

Synthesis of 1,4-phenylene-bis- (2-benzimidazolyl)

A heterogeneous mixture of 66.4 g (0.4 mole) of terephthalic acid, 199 g (1.84 mole) of ortho-phenylenediamine, 6 g of boric acid and 50 ml of N- is heated. methylpyrrolidone for a few minutes under a nitrogen atmosphere at a temperature of 70 - 80 ° C, then, with nitrogen bubbling, the mixture is heated to 190 - 200 ° C, and maintained for 5 hours at this temperature. The water formed distills and is collected by the distillation ramp. The mixture is allowed to cool to about 100 ° C and 135 ml of N-methylpyrrolidone is carefully added to it. Cool to 20 ° C, separate the solid obtained by filtration and wash with N-methylpyrrolidone, then with a mixture of N-methylpyrrolidone / ethanol

(50/50). After drying, 97 g of 1,4-phenylene-bis- (2-benzimidazolyl) are obtained (yield 78%) in the form of a white powder.

Elementary analysis for C ₂ oH ₁₄ N: calculated: C 77.40; H 4.55; N 18.05 found: C 77.18; H 4.87; N 17.95

Preparation of an aqueous dispersion of the filter: With moderate stirring using a stirrer fitted with a deflocculator, small fractions of the insoluble filter obtained in powder form are introduced into a mixture, previously homogenized, of water. and 7.5% of an alkylpolyglucoside marketed under the name Plantaren ^® by the company Henkel. The mixture is left stirring for 45 minutes, taking care not to introduce air into the suspension. Grinding :

The predispersion obtained by pumping is introduced into the bowl (capacity 150 ml) of a Dyno-Mill type ball mill marketed by the company WAB, filled up to 80% of its capacity with glass beads of 1 mm in diameter . Grinding is carried out in a closed circuit for 2 hours 30 minutes with circulation of water to avoid overheating of the preparation. The dispersion obtained is stabilized using xanthan gum. The grinding can also be carried out with circulation of the dispersion continuously during the entire grinding time.

The average diameter of the number distribution for the sample thus obtained, determined using a Mastersizer 2000 device from the company MALVERN, is 0.450 μm. The particle size profile is shown in Figure 2 of the accompanying drawing.

Examples of cosmetic compositions

Example A Cream (oil-in-water emulsion)

Mixture of glycerol mono- and distearate / PEG stearate (100 EO) *

(ARLACEL ^® 165FL from HERE) 2 g

Stearyl alcohol (LANETTE ^® 18 from HENKEL) 1 g

Palm oil stearic acid

(STEARINE ^® TP from STEARINERIE DUBOIS) 2.5 g

polydimethylsiloxane

(DOW CORNING 200 FLUID ^® from DOW CORNING 0.5 g Benzoate of C _12/15 alcohols

(WITCONOL ^® TN from WITCO) 20 g

Triethanolamine 0.5 g

38% aqueous dispersion of 1,4-Phenylene-bis- (2-benzoxazolyl) prepared according to Example 1 13.2 g Glycerin 4 g

Hexadecyl alcohol phosphate, potassium salt

(AMPHISOL ^® K from HOFFMANN LAROCHE) 0.5 g

Triethanolamine 0.3 g

Poly (acrylic acid) (SYNTHALEN ^® K 3V) 0.3 g

Curator q.s.

Demineralized water q.s.p. 100g

* PEG: polyethylene glycol, OE: ethylene oxide units

The fatty phase and the aqueous phase are heated separately to 70 ° C., then the oily phase is introduced into the aqueous phase with stirring. Stirring is continued for approximately 15 minutes and allowed to cool with slow stirring until the composition returns to room temperature.

The effectiveness of this composition is evaluated in vitro using a spectroradiometer of the SPF 290 type sold by the company Optometrics and according to the method of Diffey and Robson (BL Diffey et al., J. Soc. Cosmet. Chem. , 40, 127 - 133 (1989)) on quartz plate coated with Transpore ^® tape. The sun protection factor (SPF) is 6.1 ± 0.8. Example B

(Oil-in-water cream)

Mixture of cetylstearyl alcohol and oxyethylenated cetylstearyl alcohol (33 EO) 80/20

(HENKEL SLNNOWAX ^® AO) 7 g

Mixture of glycerol mono- and distearate

(CERASYNT ^® SD-V from ISP) 2 g Cetyl alcohol 1.5 g

polydimethylsiloxane

(DOW CORNING 200 FLUID ^® from DOW CORNING 1.5 g

Vaseline oil 15 g

Aqueous dispersion at 10% by weight of 1,4-phenylene-bis- (2-benzimidazolyl) prepared according to example 2 50 g

Curator q.s.

Demineralized water q.s.p. 100g

The oil-in-water cream is prepared as described in Example A.

The effectiveness of this composition is evaluated in vitro using a spectroradiometer of the SPF 290 type sold by the company Optometrics and according to the method of Diffey and Robson (BL Diffey et al, J. Soc Cosmet. Chem., 40 , 127 - 133 (1989)) on quartz plate coated with Transpore ^® tape. The sun protection factor (SPF) is equal to 7.6 ± 1.5.

Example C

(Oil-in-water cream)

Mixture of glycerol mono- and distearate / PEG stearate (100 EO) *

(ARLACEL ^® 165FL from HERE) 2 g

Stearyl alcohol

(L ANETTE ^® 18 from HENKEL) 1 g Stearic acid from palm oil

(STEARINE ^® TP from STEARTNERIE DUBOIS) 2.5 g

polydimethylsiloxane

(DOW CORNING 200 FLUID ^® from DOW CORNING 0.5 g

C _{12 15} alcohol benzoate (WITCONOL ^® TN from WITCO) 20 g

Triethanolamine 0.5 g

Aqueous dispersion at 10% by weight of 1,4-phenylene-bis- (2-benzimidazolyl) prepared according to example 2 50 g

Glycerin 4 g Triethanolamine 0.3 g

Poly (acrylic acid)

(SYNTHALEN ^® K of 3V) 0.3 g

hydroxypropyl methylcellulose

(METHOCEL ^® F4M from DOW CHEMICAL) 0, 1 g Preservative qs

Demineralized water q.s.p. 100g

* PEG: polyethylene glycol, OE: ethylene oxide units

The oil-in-water cream is prepared as described in Example A.

Claims

1. Insoluble organic compound filtering UV radiation in the form of particles having an average size between 10 nm and 5 μm, and corresponding to one of the formulas (I), (II) and (III) below

in which each of the symbols Y independently represents an oxygen or sulfur atom or a group NR ₂ , each of the symbols Z independently represents a nitrogen atom or a group CH, each of the symbols Ri independently represents an OH group, an atom halogen, a C ₁ alkyl group. _& , linear or branched, optionally containing a silicon atom, or a Cι- ₈ alkoxy group, linear or branched each of the numbers m is independently 0, 1 or 2, n represents an integer between 1 and 4 inclusive, p is equal to O or 1, each of the numbers q is independently equal to 0 or 1, each of the symbols R ₂ independently represents a hydrogen atom, a benzyl or Cι- ₈ alkyl group, linear or branched optionally containing a silicon atom, A represents a radical of valence n chosen from those of formulas

(b) (c) (d) (e)

(i) C ⁾ (k) (D

(m). (n) (o) in which each of the symbols R ₃ independently represents a halogen atom or a C, OR hydroxy alkyl or alkoxy group, R represents hydrogen atony or a linear or branched C _M alkyl group, c = 0 - 4, d ≈ 0 - 3, e = 0 or 1, and f = 0 - 2. 2. Insoluble organic compound of formula (I) according to claim 1, characterized in that it is chosen from 2-benzoxazol-2-yl-4-méfhylphértol, 2- (1H-benzimidazol-2-yl) -4 - methoxyphenol, 2-benzothiazol-2-ylphenol, 2,2'-bis-benzimidazole, 5.5 ', 6.6'-tetramethyl-2,2'-bis-benzimidazole, 5,5'-dimethyl-2,2'-bis-benzimidazole, 6-methoxy-2,2'-bis- benzimidazole, 2- (1H-benzimidazol-2-yl) -benzothiazole, 2- (1H-benzimidazol-2-ylbenzoxazole, N, N'-dimethyl-2,2'-bis-benzimidazole, 1,4 -phenylene- bis- (2-benzoxazolyle), 1,4-phenylene-bis- (2-benzimidazolyle), 1,3- pheny lene-bis- (2-benzoxazolyle), 1,2-phenylene-bis - (2-benzoxazolyle), 1,2-phenylene-bis- (benzimidazolyl), 1,4-phenylene-bis- (N, N'-2- ethylhexyl-2-benzimidazolyl), 1,4-phenylene -bis- (N- trimethylsilylmethyl-2-benzimidazolyle), 2- (2-benzofuranyl) - benzoxazole, 2- (benzofuranyl) -5-methylbenzoxazole and 2- (3-methyl- 2-benzofuranyl-benzoxazole). 3. Insoluble organic compound of formula (I) according to claim 2, characterized in that it is chosen from 2- [1H-benzimidazol-2-yl) benzoxazole, 6-methoxy-2,2'-bis-benzimidazole , the 2- (1H-benzimidazol-2-yl) -benzothiazole, 1,4-phenylene-bis- (2-benzoxazolyl), 1,4-phenylene-bis- (2-benzimidazolyl), 1,3-phenylene -bis- (2-benzoxazolyle), 1,2-phenylene-bis- (2-benzoxazolyle), 1,2-phenylene-bis- (2-benzimidazolyle) and 1,4-phenylene-bis- (N - trimethylsilylmethyl-2-benzimidazolyle). 4. Insoluble organic compound of formula (II) according to claim 1, characterized in that it is chosen from 2,6-diphenyl-1,7-dihydro-benzo [1,2-d; 4,5-d ' ] -di-imidazole corresponding to the formula

2,6-distyryl-1,7-dihydro-benzo [1,2-d; 4,5-d '] - di-imidazole or 2,6-di (p-tert-butylstyryl) -1,7-dihydrobenzo [1,2-d; 4,5-d '] - di-imidazole. 5. Insoluble organic compound of formula (III) according to claim 1, characterized in that it is 5,5'-bis - [(phenyl-2) - benzimidazole] of formula

H 6. An insoluble organic compound according to any one of the preceding claims, characterized in that it is in the form of particles having an average size of between 10 nm and 2 μm, preferably between 20 nm and 2 μm. 7. Cosmetic composition containing at least one insoluble organic compound filtering the UN radiation according to any one of the preceding claims, in a cosmetically acceptable carrier. 8. Cosmetic composition according to Claim 7, characterized in that the fraction of the insoluble organic compound screening out UV radiation is between 0.1% and 15% by weight and preferably between 0.2 and 10% by weight, relative to the total weight of the cosmetic composition. 9. Cosmetic composition according to one of claims 7 and 8, characterized in that it also contains one or more organic sunscreens active in the UV-A and / or UV-B range, different from those according to claims 1 to 6. 1 0. Cosmetic composition according to Claim 9, characterized in that the organic sunscreens are chosen from the following: Ethylhexyl Salicylate, Butyl Methoxydibenzoylmethane, Ethylhexyl Methoxycinnamate, Octocrylene, Phenylbenzimidazole Sulfonic Acid, Terephthalylidene Dicamphor Sulfonic Acid, Benzophenone-3, Benzophenone-4-Benzimenone-4-Benzophenone-4-Benzophenone-4-Benzimenone , Diethylhexyl Butamido Triazone, Methylene bis-Benzotriazolyl Tetramethylbutylphenol, Drometrizole Trisiloxane, and mixtures thereof. 1 1. Cosmetic composition according to any one of Claims 7 to 10, characterized in that it also contains one or more mineral pigments. 1 2. Cosmetic composition according to Claim 11, characterized in that the mineral pigments are chosen from nanopigments of metal oxides such as titanium oxide, iron oxide, zinc oxide, zirconium oxide and cerium oxide, optionally coated, and mixtures thereof. 1 3. Cosmetic composition according to Claim 12, characterized in that the nanopigments have an average particle size of between 5 nm and 100 nm, preferably between 10 nm and 50 nm. 1 4. Cosmetic composition according to any one of Claims 7 to 13, characterized in that it also contains at least one agent for artificial tanning and / or browning of the skin. 1 5. Cosmetic composition according to any one of Claims 7 to 14, characterized in that it also contains one or more formulation adjuvants chosen from fatty substances, physiologically acceptable organic solvents, thickening agents, antioxidant agents, opacifying agents, stabilizing agents, anti-foaming agents, perfumes, preserving agents, fillers, sequestering agents, propellants, pH adjusting agents, dyes and mixtures thereof. 1 6. Cosmetic composition according to any one of Claims 7 to 15, characterized in that it also contains one or more cosmetic active principles chosen from vitamins, softening agents, hydroxy acids, moisturizing agents, emollient agents, anti-radical agents, substance P antagonists, anti-inflammatory agents and mixtures of these compounds. 1 7. Cosmetic composition according to any one of Claims 7 to 16, characterized in that it constitutes a cosmetic composition intended to protect the skin or the hair, an anti-sun composition or a make-up product. . 1 8. Use of one or more compounds according to any one of claims 1 to 6 for the protection of materials sensitive to UV radiation, in particular to solar radiation 19. Composition intended to protect a material sensitive to UV radiation, in particular to solar radiation, characterized in that it comprises an effective amount of at least one compound according to any one of claims 1 to 6. 20. Use of one or more compounds according to any one of claims 1 to 6, for the preparation of a medicament intended to prevent the harmful effects of UV radiation. 21. Non-therapeutic method of protecting the skin or the hair against ultraviolet radiation, in particular solar radiation, characterized in that it consists in applying to the skin or the hair an effective amount of a cosmetic composition according to any of claims 7 to 16 or a compound according to any of claims 1 to 6. 22. Non-therapeutic method for controlling the variation in the color of the skin due to UV radiation, characterized in that it consists in applying to the skin an effective amount of a cosmetic composition according to any one of claims 7 to 15, or a compound according to any one of claims 1 to 6.