SI22859A - Sterically stabilised dispersion of hybrid inorganic-organic material in oil as preparation for protection from uv rays and procedure of preparation - Google Patents

Abstract

The subject of the invention is a sterically stabilised dispersion of hybrid inorganic-organic material in oil as a preparation for protection from harmful effects of UV rays. The invention refers also to a new cosmetic material based on composites of hybrid inorganic-organic coatings on nanocrystalline particles of TiO2 or other metal oxide, with increased dispersibility in organic vehicles and reduced formation of free radicals. Basic nanocrystalline TiO2 particles and inorganic lining made of a bridged silane are prepared according to the sol-gel procedure. Molecules of an organic sterical stabiliser are then attached covalently to the bridged silane lining, belonging to one of the following groups of compounds: higher fatty acids, linear polymers, crosslinked polymers, branched polymers or dendritic polymers. The presence of the sterical stabiliser prevents the agglomeration of TiO2 particles, improves dispersibility in organic vehicles, increases water resistance of the preparation and enables the use of high concentrations of oil suspensions which assure a high protection factor against harmful effects of UV rays.

Description

STERICALLY STABILIZED DISPERSION OF HYBRID INORGAN ORGANIC MATERIAL IN OIL AS A UV PROTECTION PREPARATION AND PREPARATION PROCEDURE

FIELD OF THE INVENTION

The subject of the invention is sterically stabilized dispersion of hybrid inorganic-organic material in oil as a preparation for protection against the harmful effects of UV rays and the process of its preparation. The present invention is in the field of pharmaceutical technology or. cosmetology, in particular in the field of the manufacture of preparations for protection against the harmful effects of UV radiation. It is based on the principles of inorganic and organic chemistry and surface chemistry and physics. It relates to a new material and process for the preparation thereof based on composites of hybrid inorganic-organic coatings on TiO ₂ nanocrystalline particles with increased dispersibility in organic solvents and reduced free radical formation. The material preparation process is based on the sol-gel process and the subsequent covalent attachment of steric stabilizers. The material prepared in this way is intended for the manufacture of various tanning preparations.

The state of the art

Physical UV filters, the most important of which are TiO ₂ and ZnO, were detected very early on, but their use was cosmetically unacceptable, since they made the skin whitish due to its opacity. Transparency is conditioned by the average particle size. Thus, TiO ₂ particles are transparent if the average particle size is 20 to 100 nm, and ZnO particles when the particles are 40 to 100 nm in size. Not only the input particle size but also the average particle size of the final preparation is important. Namely, the agglomeration of particles in a preparation can occur, and the resulting agglomerates are no longer transparent.

Particles of this size absorb UV light in addition to the scattering (nanocrystalline TiO ₂ absorbs about 70% of the incident UV light). Absorption of UV radiation, however, can lead to the formation of free radicals, which directly or through reaction with other constituents of the tanning agent, cause cell damage.

The extent of the detrimental photocatalytic properties of nanocrystalline physical UV filters can be reduced if the particles are coated with compounds that form hydrated oxides and act as traps for hydroxyl radical scavengers. The latter can be prepared e.g. by the flame reaction of nanocrystalline TiO ₂ and functionalized silanes [Deller K, Kemer D, Meyer J; Surface-2modified titanium dioxide, United States Patent 6663851], thereby altering surface properties. Most often, the sol-gel process is used to dress these materials. The sol-gel process can be used to prepare tetraethylorthosilicate (TEOS), bis-1, 2-triethoxysilylethane (BTSE) and aluminum oxide coatings, thereby reducing adhesion and mechanical resistance, making this material useful for coating kitchenware [Shoup R, Rice N, Simes D, Sky J, Georges GT: Abrasion and impact resistant coating compositions, and articles coated therewith, United States Patent 6905772].

The sol-gel process was also used to make xerogel based sunbathing preparations. Chemical and physical UV filters may be incorporated into the structure of xerogels prepared by sol-gel process based on the starting compounds of the general chemical formula M (R) n (P) m (where M represents a metal or a metal, R a hydrolysable substituent, P a non-polymerizable substituent , and n can be 2-6 and m can be 0-6) [Sunscreens for sun radiation protection, WO / 1998/031333]. According to the sol-gel process, SiO ₂ coatings on silicic acid-based TiO ₂ nanoparticles and TEOS were also prepared for use as UV filters [Ishii N, Wada K, Sekiguchi K, Takama M, Ito S, Yano K, Saito Y , Kawasaki K: Cosmetics, silica-coated metal oxide powder and production method therefore, United States Patent 6235270]. Although such coatings reduce the amount of free radical formation, due to their strong hydrophilicity, such composites are not dispersible in oily solvents but only in aqueous solvents. In this case, they may be subject to microbial contamination, so it is necessary to resort to preservatives, which, like chemical UV filters, can cause hypersensitivity reactions. Hydrophilic preparations are also not water repellents, which is otherwise desirable. The use of oil solvents can eliminate the risk of microbial contamination and increase the water resistance of sunscreen products, but the surfaces of UV filters for dispersibility in oil solvents must be hydrophobic.

The latter can be achieved by coating the particles with silicic acid or its precursors and subsequently hydrophobizing the surface of the coating with silicone oils, organic alkoxysilanes and high fatty acid salts [Wada K, Ishii N, Irie M, Sekiguchi K, Takama M: Cosmetic preparation, surface- hydrophobized silica-coated metal oxide particles, silica-coated metal oxide salt, and processes for producing these, United States Patent 6534044], but the process contains many steps and is therefore lengthy and industrially less acceptable. Coating with a wide range of silanes and siloxanes has also improved the photostability of chemical UV filters [Chodorowski S, Xavier Quinn F, Sanchez C: A method for improving the UV radiation stability of photosensitive sunscreen filters (United States Patent 6607713), but

The preparation process of these composites involves at least one surfactant, which, due to the irritability and allergenicity of the chemical UV filters themselves, can further irritate the skin and cause hypersensitivity reactions. Increased photostability and hydrophobicity of the surface and good transparency for visible light of mixed metal oxides as UV filters can be achieved simultaneously by coating particles with one or more compounds from the group of silicone oils, alkoxysilanes (eg TEOS), silane coupling reagents (this includes BTSE) or salts of higher fatty acids. In these cases, the fatty acids are only adsorbed onto the particles by spray drying or adsorption from solutions - this may increase the hydrophobicity, but desorption can occur in the oily solvents; there is no steric stabilization, so such preparations are not stable [Ishii N, Wada K, Takama M: Silica-coated mixed crystal oxide particle, production process and cosmetic material using the same, United States Patent 7347986],

Although the coating of physical UV filters has solved the problem of free radical formation and dispersibility in oily vehicles, the suspensions thus prepared are not completely resistant to particle aggregation, because the particles have a large interaction surface due to their small size and thus large specific surface area and may therefore they agglomerate. The suspensions of this type are thermodynamically unstable, since the particles agglomerate irreversibly after approaching each other. Agglomeration eliminates the transparency in the visible part of the spectrum and reduces the coverage and thus the skin's protection after application. Due to the tendency to aggregate, it is also not possible to achieve high concentrations of the suspension, and the particles can also agglomerate under the influence of mechanical stresses that can occur during transport of the product.

The problem, which has not been solved so far, is that the particles are not resistant to irreversible agglomeration, so it is not possible to achieve high concentrations of suspensions and transparency for visible light over a long period of time. Also known preparations have a low water resistance, so repeated application is necessary after contact with water.

-4Description of a solution to a problem with implementation examples

According to the invention, the problem is solved by first coating the particles of the physical UV filter with a hydrophobic hybrid silane coating, which is then covalently bound by a steric stabilizer which does not form a compact coating. The particles thus obtained, i.e., particles with one coating and steric stabilizer, are then dispersed in a suitable oil solvent. The dispersions thus obtained can then be used to make any derivatives used in the cosmetic industry.

In such a product, due to the hybrid silane coating, the possibility and extent of free radical formation are reduced. Because the coating is hydrophobic, the coated particles are better dispersible in oil. The attachment of the steric stabilizer, however, stabilizes the dispersed coated particles, making them resistant to agglomeration. This ensures transparency over a longer period of time and allows high concentrations of suspensions to be achieved. Because both the liner and the steric stabilizer are hydrophobic, it is possible to prepare oil suspensions which are extremely water repellent, so there is no need for repeated application to the skin. Due to their improved oil dispersibility and resistance to particle agglomeration, such oil suspensions are already at low concentrations more effective than existing sun oils based on chemical UV filters. The efficiency can be increased by increasing the particle concentration enabled by agglomeration resistance. The efficiency can be evaluated by spectroscopically measuring the fraction of UV light permeable and is shown in Figure 2 in the case of a 2 mm thick dispersion layer with 0.5% by weight of the preparation of embodiment A in olive oil.

The process of preparing both the lining and the attachment of the steric stabilizer is simple and economical and therefore suitable for industrial production.

The invention will be described on the basis of embodiments and illustrations showing:

Figure 1: FTIR spectrum of the sample of Embodiment B 2 .. At 960 cm &^lt; ^-1 &^gt;

Figure 2: Diagram of the percentage of transmitted UV-B (280-320 nm) and UV-A (320-400 nm) light of a 2 mm thick dispersion layer with 0.5% by weight of the preparation of embodiment A in olive oil.

The object of the invention is a kinetically stabilized suspension with physical UV filters, which in the proposed solution is prepared by steric stabilization of the particles, which is carried out by covalently attaching the steric stabilizers via -Si-O-C (= O) R, -Si-O-R or similar bonds. R represents longer linear or branched conformationally moving compounds with functional groups that allow covalent attachment to silanol groups and in no case form a compact liner, but are attached to the silane liner with only one to ten bonds. Such compounds belong to the group of higher fatty acids, preferably oleic, stearic and / or palmitic acid, linear polymers, preferably polyethylene glycols, nylon and / or polydimethylsiloxane, cross-linked polymers, preferably miscellaneous rubbers, branched polymers, preferably polyethylene ether densities, preferably polyethylene ether densities dendrons. The steric stabilizer causes a repulsive interaction that prevents the particles from approaching the distance at which attractive der Waals interactions begin to work. The steric repulsive interaction thus represents an insurmountable energy barrier of agglomeration that makes the suspension kinetically stabilized.

An additional positive effect of steric stabilizer is the improved dispersibility in organic solvents and the increased water resistance of the preparation.

The particles of the physical UV filter in the present invention are from the metal oxide group, preferably from the titanium group, preferably rutile, anatas, brookite, TiO ₂ -B, or a mixture of the above forms, zinc, cerium, zirconium, iron oxide with a size of 20-100 nm and n

specific surface area of 10-200 m / g. The thickness of the silane lining, preferably bridged, simple or functionalized silane, is 0.5 to 50 nm. A sterile stabilizer is covalently attached to the surface of such a coating, so the coating must be reactive. The reactivity of the coating is adjusted using silane, in which a positive inductive group is attached to the silicon atom, which increases the electron density on the silanol group and thus increases the reactivity with the electrophilic activated steric stabilizer groups. Bridging silane represents a compound of the general chemical formula (RiO) 3-Si-R ₂ -Si- (ORi) 3, wherein Ri is a linear or branched alkyl group of 1-15 carbon atoms and R ₂ is a non-hydrolyzing linear, branched or cyclic alkylene or an allylene group which may be substituted or unsubstituted. Preferably, bis-1,2- (triethoxysilyl) ethane (BTSE) is used from this group. Simple or functionalized silane is a compound of the general chemical formula (RiO) 4-Si or (RiO) 3-Si-X; wherein R1 is a linear or branched alkyl group of 1-15 carbon atoms and X is a non-hydrolyzing hydrophilic, hydrophobic, ionizing or non-ionizing, one or more atomic linear, branched or cyclic, saturated, unsaturated or aromatic functional group. If

-6 T1O2 metal oxide forms a covalent bond during preparation of the bridged, simple or functionalized silane between T1O2 and the coating, which is observed in the FTIR spectrum as a peak with a maximum at 950-965 cm &^lt; ^-1 &^gt;, as shown in Figure 1. Steric stabilizer , which is covalently attached to the coating, represents longer linear or branched conformationally moving compounds and is attached to the silane coating with only one or more bonds, said compounds being in the group of higher fatty acids, preferably oleic, stearic and / or palmitic acid , linear polymers, preferably polyethylene glycols, nylon and polydimethylsiloxane, crosslinked polymers, preferably miscellaneous gums, branched polymers, preferably low density polyethylene or dendritic polymers, preferably dendrons. The oily solvent in which the coated particles are dispersed with a covalently attached steric stabilizer is an oil or a mixture of oils from a group of dermatologically acceptable natural or synthetic oils.

The described coating is prepared by a basicly catalyzed sol-gel process comprising one or more organic solvents from the group of alcohols, ketones, ethers or esters, and water, a basic catalyst which may be ammonia, an ammonia derivative, an ammonium salt of organic or inorganic acid, an alkali metal or alkaline earth hydroxide, alkali or alkaline earth carbonate or hydrogen carbonate or any other basic compound, and does not include any surfactant that may otherwise cause hypersensitivity reactions.

The steric stabilizer is attached to the coating in the form of an activated derivative, preferably an acid halide, anhydride, activated ester, a coupled compound obtained preferably with a dicyclohexylcarbodiimide coupling reagent (DCC) or a similar coupling reagent, wherein the activation and coupling reactions are carried out in or without a several stages. The product obtained by the coupling reaction of the steric stabilizer is isolated, preferably by filtration, and dried until the mass of the product is changed. The dispersion of sterically stabilized hybrid inorganic-organic material described is used in various cosmetic products as a preparation for protection against the harmful effects of UV rays, preferably preferably for the manufacture of creams, lotions, aerosols, gels or 'stick' or other cosmetic preparations.

-7Example A:

1. Preparation of bridging silane lining:

First, prepare a suspension of TiO ₂ P25 (Degussa) in purified water in a flat-bottomed flask by weighing 600 mg of TiO ₂ and suspending it in 300 g of purified water and stopping the flask with a stopper. The suspension was then homogenized in an ultrasonic bath at 50 ° C for 30 min. The suspension was then further homogenized for 15 min at room temperature with a magnetic stirrer at 700 rpm.

Meanwhile, prepare the reaction mixture in a 100 ml beaker by mixing 46 g ethanol (Riedel de Haen), 11 g BTSE (ABCE GmbH) and 6.5 g water and cover the beaker with parafilm. Weigh another 3 g of a 25% ammonia solution (Merck) in a 10 ml beaker and close the beaker.

After 15 min of homogenization of the TiO ₂ suspension with a magnetic stirrer, the reaction mixture was added first with stirring and then a solution of ammonia was added dropwise. The flask was then covered again and the mixture thus prepared was stirred with a magnetic stirrer at room temperature for 90 minutes.

After completion of the reaction, the product was filtered off by suction through a membrane filter. The filtrate was discarded and the product was dried to dryness under normal pressure and 50 ° C.

2. Attachment of steric stabilizer:

Weigh, in a 100 ml flask, 100 mg of the sample prepared by the procedure according to point 1 (that is, the sample with silanol groups on the surface) and 100 mg of lauric acid (SAFC). Weigh 50 ml of dichloromethane (Merck) with a measuring cylinder. Weigh separately 100 mg of dicyclohexylcarbodiimide (DCC) (Aldrich). Pour the measured dichloromethane into a sample flask of 1 and lauric acid and add DCC and cover the flask with a stopper. The reaction mixture thus prepared is placed on a magnetic stirrer, added to the tip of the catalyst spatula (dimethylaminopyridine-DMAP) and adjusted to 500 rpm. After stirring for 12 hours at room temperature, the product was filtered off by suction through a membrane filter and washed 5 times with dichloromethane and the product obtained was dried for 48 hours at 50 ° C.

-83. Dispersion of the material from the above process (item 2) into olive oil mg of the material obtained by the process under item 2 is dispersed in 39,980 g of olive oil (Lex). The dispersion was then dispersed for 30 min in an ultrasonic bath.

Example B:

1. Preparation of bridging silane lining:

First, prepare a suspension of TiO ₂ P25 (Degussa) in purified water in a flat-bottomed flask by weighing 500 mg of TiO ₂ and suspending it in 100 g of purified water and stopping the flask with a stopper. The suspension was then homogenized in an ultrasonic bath at 50 ° C for 30 min. The suspension was then further homogenized for 15 min at room temperature with a magnetic stirrer at 700 rpm.

Meanwhile, prepare the reaction mixture in a 100 ml beaker by mixing 40 g ethanol (Riedel de Haen), 30 g BTSE (ABCE GmbH) and 15 g water and cover the beaker with parafilm. Weigh 3.5 g of a 25% ammonia solution (Merck) in a 10 ml beaker in parallel and close the beaker.

After 15 min of homogenization of the TiO ₂ suspension with a magnetic stirrer, the reaction mixture was added first with stirring and then a solution of ammonia was added dropwise. The flask was then covered again and the mixture thus prepared was stirred with a magnetic stirrer at room temperature for 90 minutes.

After completion of the reaction, the product was filtered off by suction through a membrane filter. The filtrate was discarded and the product was dried to dryness under normal pressure and 50 ° C.

2. Attachment of steric stabilizer:

Weigh, in a 100 ml flask, 100 mg of the sample prepared by the procedure of point 1 (that is, a sample of silanol groups on the surface) and suspend it in 50 ml of dichloromethane (Merck). Cover the flask with a rubber septa. Separately, 0.1 ml of stearoyl chloride (Aldrich) is added to the syringe and added to the suspension through the septa. The reaction mixture thus prepared is placed on a magnetic stirrer and the stirrer is adjusted to 500 rpm. After stirring for 12 hours at room temperature, the product was filtered off by suction through a membrane filter and washed 5 times with dichloromethane and the product obtained was dried for 48 hours at 50 ° C.

-93. Dispersion of the material from the above process into coconut oil mg of the material obtained by the process described under 2 is dispersed in 30 g of coconut (SICTIA) oil. The dispersion was then dispersed for 30 min in an ultrasonic bath.

Example C:

1. Preparation of bridging silane lining:

First, prepare a suspension of TiO ₂ P25 (Degussa) in purified water in a flat bottom flask by weighing 1 g of TiO ₂ and suspending it in 200 g of purified water and close the flask with a stopper. The suspension was then homogenized in an ultrasonic bath at 50 ° C for 30 min. The suspension was then further homogenized for 15 min at room temperature with a magnetic stirrer at 700 rpm.

Meanwhile, prepare a reaction mixture in 100 ml beakers by mixing 100 g ethanol (Riedel de Haen), 50 g BTSE (ABCE GmbH) and 40 g water and cover the beaker with parafilm. Weigh another 5 g of 25% ammonia solution (Merck) in a 10 ml beaker and close the beaker.

After 15 min of homogenization of the TiO ₂ suspension with a magnetic stirrer, the reaction mixture was added first with stirring and then a solution of ammonia was added dropwise. The flask was then covered again and the mixture thus prepared was stirred with a magnetic stirrer at room temperature for 90 minutes.

After completion of the reaction, the product was filtered off by suction through a membrane filter. The filtrate was discarded and the product was dried to dryness under normal pressure and 50 ° C.

2. Attachment of steric stabilizer:

Weigh, in a 100 ml flask, 100 mg of the sample prepared by the procedure of point 1 (that is, a sample of silanol groups on the surface) and 100 mg of palmitic acid anhydride (Aldrich). Weigh 50 ml of dichloromethane (Merck) with a measuring cylinder. Pour the measured dichloromethane into a flask with sample 1 and palmitic acid anhydride and cover the flask with a stopper. The reaction mixture thus prepared is placed on a magnetic stirrer, which is adjusted to 500 rpm. After stirring for 12 hours at room temperature, the product was filtered off by suction through a membrane filter and washed 5 times with dichloromethane and the product obtained was dried for 48 hours at 50 ° C.

-103. Dispersion of the material from the above process into almond oil g The material obtained by the process described under 2 is dispersed into 24 g of almond (SICTIA) oil. The dispersion was then dispersed for 30 min in an ultrasonic bath.

Exemplary examples merely explain the patent and do not limit it in its essence.

Claims (14)

Patent claims 1. Dispersion of sterically stabilized hybrid inorganic-organic material in oil, characterized in that it contains a metal oxide, a silane-bridged coating and a covalently attached steric stabilizer containing longer linear or branched conformationally moving compounds of the higher fatty acid group, preferably oleic, stearic acid and / or palmitic acid, linear polymers, preferably polyethylene glycols, nylon and / or polydimethylsiloxane, crosslinked polymers, preferably miscellaneous rubbers, branched polymers, preferably low density polyethylene, dendritic polymers, preferably dendrons, and allowing for covalent bonding to ten silanol groups. Dispersion of sterically stabilized hybrid inorganic-organic material in oil according to claim 1, characterized in that the particle size of the metal oxide, preferably selected from the group titanium, zinc, cerium, zirconium, iron oxide, from 20-100 nm, with a specific surface area from 10-200 m / g. Dispersion of sterically stabilized hybrid inorganic-organic material in oil according to the preceding claims, characterized in that the metal oxide in the case of titanium dioxide is rutile, anatas, brookite, TiO ₂ -B or a mixture of the above forms. Dispersion of sterically stabilized hybrid inorganic-organic material in oil according to the preceding claims, characterized in that the thickness of the coated silane coating on the metal oxide particles according to claims 2 and 3 is between 0.5 and 50 nm. Dispersion of a sterically stabilized hybrid inorganic-organic material in oil according to claim 4, characterized in that a steric stabilizer is attached covalently to the coating. Dispersion of sterically stabilized hybrid inorganic-organic material in oil according to claims 4 and / or 5, characterized in that the coating is composed of bridged silane and the starting material for the coating is the general chemical formula (R ^ fr-Si-RZ-Sri / OR ¹ ^, wherein R ^{1 is a} linear or branched alkyl group of 1-15 carbon atoms and R 1 is a non-hydrolyzing linear, branched or cyclic alkylene or alylene group which may be substituted or unsubstituted. -127. Dispersion of sterically stabilized hybrid inorganic-organic material in oil according to any one of claims 4 to 6, characterized in that the starting material for the coating of silane is 4-6 bis-1,2- (triethoxysilyl) ethane (BTSE). Dispersion of sterically stabilized hybrid inorganic-organic material in oil according to any one of claims 1 to 3, 5, 8, characterized in that the coating is composed of simple or functionalized silane of the general chemical formula (R'O) 4-Si or ( R 10) 3-Si-X; wherein R ^{1 is a} linear or branched allylic group of 1-15 carbon atoms and X is a non-hydrolyzing hydrophilic, hydrophobic, ionizing or non-ionizing, one or more atomic linear, branched or cyclic, saturated, unsaturated or aromatic functional group. Dispersion according to any one of claims 2 to 8, characterized in that the metal oxide coated in the FT-IR spectrum has a characteristic absorption peak with a maximum at 955-965 cm ^-1 corresponding to the vibration of the Ti-O-Si bond. Dispersion of sterically stabilized hybrid inorganic-organic material in oil according to any one of claims 4 to 8, characterized in that a sterile stabilizer containing longer linear or branched conformationally moving compounds and having only one to ten bonds is covalently attached to the coating. attached to a silane coating, said compounds being in the group of higher fatty acids, preferably oleic, stearic and / or palmitic acid, linear polymers, preferably polyethylene glycols, nylon and polydimethylsiloxane, crosslinked polymers, preferably miscellaneous gums, branched polymers, preferably polyethers or dendritic polymers, preferably dendrons. Dispersion of sterically stabilized hybrid inorganic-organic material in oil according to the preceding claims, characterized in that the particles are coated with a coating to which a covalently bonded steric stabilizer is dispersed in an oil solvent, which is an oil or a mixture of oils of the dermatologically acceptable natural group or synthetic oils. 12. A process for preparing a dispersion of a sterically hybrid inorganic-organic material in oil according to claim 1, characterized in that the coating is prepared by a basicly catalyzed sol-gel process comprising one or more organic solvents from the group of alcohols, ketones, ethers -13 or esters and water, a basic catalyst, which may be ammonia, ammonia derivative, ammonium salt of organic or inorganic acid, alkali or alkaline earth metal hydroxide, alkali or earth alkali carbonate or hydrogen carbonate or any other basic compound, and does not include any surfactant Method according to claim 12, characterized in that the lining preparation is carried out in the following steps: a. suspending from 50 mg to 20 g of the particles of claims 2 and 3 in 100 g of water, b. homogenization of the resulting suspension, preferably by ultrasound or agitation, c. separate preparation of the reaction mixture, which is prepared by mixing 0.5 to 200 g of the starting material of claims 6.7 or 8, 6.5 to 465 g of organic solvent, 0 to 100 g of water, and such an amount of basic catalyst to provide an appropriate pH mixtures, (or by mixing the amount of the substances just mentioned which give such mass ratios), d. adding the reaction mixture from step c to the suspension prepared in steps a and b e. the stepwise addition of the catalyst of claim 12 to the reaction mixture prepared in step d, f. stirring the reaction mixture obtained in step e for 1 to 25 hours at room temperature or 25 to 100 ° C, Mr Rücker isolation of the solid product obtained in step f, preferably by filtration, h. drying the isolated solid obtained in step g at room temperature or from 25 to 100 ° C until the mass no longer changes. A method according to claim 12, characterized in that the process of covalently attaching a steric stabilizer to the coating involves attaching a steric stabilizer in the form of an activated derivative, preferably an acid halide, anhydride, an activated ester, a coupled compound, preferably obtained with a dicyclohexylcarbodi coupling reagent (DCI) or dicyclohexylcarbodi similar coupling reagents wherein the activation and coupling reactions take place in the non-aqueous medium in one to five stages. 15. The method of claim 14, characterized in that the product is isolated after completion of the reaction, preferably by filtration and dried until the mass no longer changes. -1416. Use of dispersion of sterically stabilized hybrid inorganic-organic material in cosmetic oil as a preparation for protection against the harmful effects of UV rays, preferably for the manufacture of creams, lotions, aerosols, gels or 'stick' or other cosmetic preparations.