KR101933524B1 - Silica-based composite powder for uv shielding, method for preparing the same and compositon comprising the same - Google Patents

Abstract

The present invention relates to a silica-based composite powder for ultraviolet shielding, and more particularly relates to a silica-based composite powder for porous silica; An inorganic ultraviolet blocking agent doped on the surface inside the pores of the porous silica; An organic UV blocking agent impregnated inside the pores of the porous silica; And a coating layer coated on the outer surface of the porous silica, a method for producing the silica-based composite powder, and a composition comprising the same.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a silica-based composite powder for ultraviolet shielding, a method for producing the same, and a composition comprising the same. BACKGROUND ART [0002]

The present invention relates to a silica-based composite powder for ultraviolet shielding, a method for producing the same, and a composition containing the same.

Recently, the destruction of the ozone layer has accelerated due to environmental pollution, which has a great influence on the environment and human body. Particularly, the destroyed ozone layer can not block the ultraviolet rays of the sunlight, and the ultraviolet rays thus introduced reach the surface of the earth. As a result, the human body and the outdoor structure are exposed to ultraviolet rays reaching the surface of the earth.

In this regard, ultraviolet rays emitted from sunlight can be divided into ultraviolet-A, ultraviolet-B, and ultraviolet-C (hereinafter referred to as UV-A to UV-C) depending on the wavelength range. Specifically, ultraviolet rays having a wavelength range of 320 nm to 400 nm are UV-A, ultraviolet rays having a wavelength range of 290 nm to 320 nm are UV-B, and ultraviolet rays having a wavelength range of 200 nm to 290 nm are divided into UV-C (See FIG. 1). In general, about 6% of UV-A and UV-B reach the surface, UV-C is absorbed and scattered on the surface of the ozone layer and the atmosphere and reaches the surface. The amount of C reaching the surface is also increasing.

When ultraviolet rays reaching the surface of the earth are exposed to the human body, there are advantages such as synthesis of vitamin D in the body, treatment of skin diseases, sterilization effect and the like, but sunlight, skin cancer, skin Aging, photosensitivity skin disease, and mutagenesis. In particular, UV-A penetrates into the dermis of the skin, mainly causing pigmentation and aging of the skin, and related to the development of photosensitivity dermatitis. UV-B penetrates into the epidermis of the skin and the upper part of the dermis with a short- Burns, pigmentation and skin cancer.

Thus, in order to prevent the side effects of sunlight, especially ultraviolet light, attempts have been made to block ultraviolet light. Specifically, the ultraviolet screening agent is divided into an organic ultraviolet screening agent and an inorganic ultraviolet screening agent. The organic ultraviolet screening agent blocks ultraviolet rays through absorption of ultraviolet rays. The inorganic ultraviolet screening agent absorbs ultraviolet rays, reflects and scatters Thereby blocking ultraviolet ray penetration.

These organic UV-blocking agents contain at least one UV-absorbing component in the blocking agent, such as para-aminobenzoic acid (PABA) blocking UV-B; PABA esters such as amyldimethyl PABA, octyldimethyl PABA and the like; Cinnamates such as cyanoate and the like; Salicylates; And campers, and benzophenone and dibenzoylmethane which block UV-A. However, the components of the organic ultraviolet screening agent are effective in absorbing and shielding ultraviolet rays, but they are irritated to the skin or eyes, thereby causing problems such as contact dermatitis and photosensitivity reaction, It restricts the use itself or limits usage.

On the other hand, the inorganic UV blocking agent can protect the skin from ultraviolet rays and realize ultraviolet ray blocking effect against UV-A and UV-B through absorption, reflection and scattering of ultraviolet rays by using metal oxides which are present in nature Unlike the organic UV blocking agent, there is no side effect such as contact dermatitis, and it is not easily removed even in contact with water. However, there is a problem that the metal oxide particles are agglomerated, thereby realizing a desired formulation It is difficult to maintain an effective content, and metal oxide particles are present in a coagulated state at the time of application, and the refractive index is increased to cause a cloudiness phenomenon (see FIG. 5).

The object of the present invention is to solve the problems mentioned in the background of the present invention by reducing the skin irritation caused by the organic ultraviolet screening agent and at the same time improving the dispersibility of the particles of the inorganic ultraviolet screening agent, Thereby improving formulation stability and whitening.

That is, the present invention was conceived to solve the problems of the background art of the present invention, and it is an object of the present invention to provide a cosmetic composition which not only has a high ultraviolet barrier property but also excellent spreadability and transparency by using an organic ultraviolet screening agent and an inorganic ultraviolet screening agent simultaneously, And a process for producing the same, and a composition comprising the same.

According to an embodiment of the present invention, there is provided a porous silica material comprising: porous silica; An inorganic ultraviolet blocking agent doped on the surface inside the pores of the porous silica; An organic UV blocking agent impregnated inside the pores of the porous silica; And a coating layer coated on the outer surface of the porous silica.

The present invention also relates to a method for producing a porous silica, comprising: (S1) preparing porous silica by emulsification; (S2) doping an inorganic ultraviolet screening agent on the inside surface of the pores of the porous silica prepared in the step (S1) to prepare a porous silica doped with an inorganic ultraviolet screening agent on the surface inside the pores; (S3) of impregnating porous silica doped with an inorganic UV-blocking agent on the surface of the pores produced in the step (S2), with an organic UV-blocking agent to prepare porous silica impregnated with an organic UV-blocking agent in the pores; And (S4) coating the outer surface of the porous silica impregnated with the organic UV-blocking agent in the pores produced in the step (S3).

The present invention also provides a composition comprising the silica-based composite powder for shielding ultraviolet rays.

According to the silica-based composite powder of the present invention, nanosized inorganic UV-blocking agents are chemically doped into the pores of the porous silica. Thus, when the UV-blocking agent is formulated, excellent dispersibility is exhibited without any physical dispersion, As a result, the light scattering phenomenon is lowered and the whitening phenomenon does not occur, and the particle size of the metal oxide doped in the pores of the porous silica is very small, thereby increasing the transparency. In addition to the inorganic sunscreen added to the conventional ultraviolet screening agent When using the same amount of the inorganic ultraviolet screening agent, the surface area of the metal oxide particles capable of absorbing the ultraviolet ray is increased, thereby exhibiting a higher ultraviolet ray blocking index.

Further, according to the silica-based composite powder of the present invention, by coating the surface of the porous silica, it is possible to prevent elution of the organic-based ultraviolet screening agent impregnated into the inside of the porous silica when the ultraviolet screening agent is formulated, By including the organic sunscreen agent that does not come into direct contact with the skin to reduce skin irritation and has an ultraviolet screener that is far superior to the inorganic sunscreen agent, the ultraviolet screener has a higher ultraviolet screening index than the organic sunscreen free agent There is an effect indicating.

1 is a schematic diagram showing a wavelength region of light and a wavelength region of ultraviolet rays (UV-A to C).
FIG. 2 is a schematic view showing a manufacturing process of the silica-based composite powder for ultraviolet shielding according to the present invention.
FIG. 3 is a schematic view showing a manufacturing process of the porous silica according to the present invention.
4 is a graph showing specific surface area, pore volume, and pore size of the porous silica prepared according to Examples 1 to 3 of the present invention.
5 is a schematic view showing the particle dispersion form of the silica and titanium dioxide composite powder in the existing ultraviolet screening agent and the particle dispersion form of the silica-based composite powder in the ultraviolet screening agent containing the silica-based composite powder according to the present invention.

The terms and words used in the description of the present invention and in the claims should not be construed to be limited to ordinary or dictionary terms and the inventor should appropriately interpret the concepts of the terms appropriately The present invention should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention.

Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.

The silica-based composite powder for ultraviolet shielding according to an embodiment of the present invention includes porous silica; An inorganic ultraviolet blocking agent doped on the surface inside the pores of the porous silica; An organic UV blocking agent impregnated inside the pores of the porous silica; And a coating layer coated on the outer surface of the porous silica. When the above-mentioned silica-based composite powder for ultraviolet shielding is applied as an ultraviolet screening agent, the dispersibility is improved by the porous silica and the aggregation of the inorganic ultraviolet screening agent from the inorganic ultraviolet screening agent doped on the surface of the inside of the pores of the porous silica is prevented, And the effect of blocking ultraviolet rays from the organic ultraviolet screening agent impregnated into the pores of the porous silica is remarkably increased, and at the same time, the elution of the organic ultraviolet screening agent from the coating layer is prevented (see FIG. 5).

According to one embodiment of the present invention, the porous silica may have an average particle diameter of 1 to 10 mu m, 1 to 8 mu m, or 1 to 5 mu m, and when the ultraviolet screening agent is formulated within this range, This is an excellent effect. As another example, the porous silica may have a pore size of 10 nm or less, 1 nm to 10 nm, or 3 nm to 8 nm, and within this range, the particle size of the metal oxide doped into the pores of the porous silica is very high The transparency is increased and the surface area of the metal oxide particles capable of absorbing ultraviolet rays increases when the same amount of the inorganic ultraviolet ray blocking agent as the inorganic ultraviolet ray blocking agent added to the existing ultraviolet ray blocking agent is added to exhibit a higher ultraviolet ray blocking index.

The 'pore size' means the size of the pores present in the porous silica, meaning that the size of the pores existing in the porous silica is distributed within the range of the pore size, Can mean the average particle size of the pores.

According to an embodiment of the present invention, the porous silica may have a specific surface area of 100 m ² / g to 900 m ² / g, 200 m ² / g to 800 m ² / g, or 400 m ² / g to 700 m ² / g, and the pore volume may be from 0.6 cm ³ / g to 0.9 cm ³ / g, from 0.65 cm ³ / g to 0.85 cm ³ / g, or from 0.7 cm ³ / g to 0.8 cm ³ / g Within this range, the particle size of the metal oxide doped in the pores of the porous silica within this range is very small, so that the transparency is increased. As another example, the porous silica may have an oil absorption of 0.5 cm ³ / g to 2.0 cm ³ / g, 0.7 cm ³ / g to 1.8 cm ³ / g, or 0.8 cm ³ / g to 1.5 cm ³ / g, Within this range, the surface of the inside of the pores of the porous silica is sufficiently doped with the inorganic ultraviolet screening agent, and the organic ultraviolet screening agent is sufficiently impregnated.

According to one embodiment of the present invention, the doping amount of the inorganic ultraviolet screening agent and the amount of the organic ultraviolet screening agent impregnated can be adjusted according to the specific surface area, pore volume, and pore size of the porous silica in the preparation of the silica- .

According to an embodiment of the present invention, the inorganic UV blocking agent means an inorganic compound exhibiting an ultraviolet ray shielding effect, and may be, for example, a metal oxide. Specific examples thereof include titanium dioxide, a metal oxide of zinc, Zinc oxide, and cerium oxide, which are metal oxides of cerium. In this case, the ultraviolet barrier property is excellent. According to an embodiment of the present invention, the inorganic ultraviolet screening agent is present in a form of being doped on the surface of the inside of the pores of the porous silica. In this case, the doped inorganic ultraviolet screening agent may be the metal oxide itself, Derived functional group in which a metal oxide is bonded to the surface inside the pores of the porous silica by a dehydration condensation reaction between a hydroxyl group (-OH) existing on the surface of the pores of the porous silica and an alkoxy group (-OR) of the metal alkoxide .

According to an embodiment of the present invention, the amount of the inorganic ultraviolet screening agent doped on the surface of the inside of the pores of the porous silica is 5 to 30 parts by weight, 5 to 20 parts by weight , Or 10 parts by weight to 20 parts by weight, and the effect is obtained that the inorganic ultraviolet blocking agent is uniformly doped into the surface of the inside of the pores of the porous silica within this range.

According to one embodiment of the present invention, the organic UV-blocking agent means an organic compound exhibiting an ultraviolet blocking effect. Specific examples thereof include oxybenzone, avo benzone, octyl methoxycinnamate Octyl salicylate, homosalate, octocrylene, menthyl anthranilate, para-aminobenzoic acid (PABA), amyl dimethyl It may be at least one selected from the group consisting of PABA (amyl dimethyl PABA), octyl dimethyl PABA, cinoxate, and 4-methylbenzylidene camphor. In this case, Is very effective.

According to an embodiment of the present invention, the impregnation amount of the organic ultraviolet screening agent is 0.1 cm ³ / g to 1.5 cm ³ / g, 0.3 cm ³ / g to 1.2 cm ³ / g, or 0.5 cm ³ / ³ / g. Within this range, organic pores of the porous silica are evenly impregnated into the pores of the porous silica, and thus the ultraviolet barrier property is extremely excellent.

According to one embodiment of the present invention, the coating layer is a coating layer coated on the surface of the porous silica doped with an inorganic ultraviolet blocking agent on the inside surface of the pores and impregnated with an organic ultraviolet blocking agent in the pores, And preventing the organic UV-ray blocking agent impregnated inside the pores of the porous silica from leaching out of the pores of the porous silica at the time of formulation or later coating, wherein the coating layer is derived from an alkoxysilane compound Coating layer. According to an embodiment of the present invention, the coating layer is coated on the outer surface of the porous silica. The coating layer may be an alkoxysilane compound itself, or may be formed on the outer surface of the porous silica. May be an alkoxysilane compound-derived functional group in which an alkoxysilane compound is bonded to the outer surface of the porous silica by a dehydration condensation reaction between an existing hydroxy group (-OH) and an alkoxy group (-OR) of an alkoxysilane compound , And the alkoxysilane compound-derived functional group may be a condensed compound in which the functional groups derived from the respective alkoxysilane compounds are condensed with each other.

According to an embodiment of the present invention, the alkoxysilane-based compound may be an alkoxysilane-based compound represented by the following general formula (1). In this case, the effect of improving the dispersibility is improved.

[Chemical Formula 1]

R ¹ may be hydrogen or a monovalent hydrocarbon group having 1 to 30 carbon atoms, R ² may be an alkoxy group having 1 to 30 carbon atoms, m may be 0, 1, 2, or 3, n may be 1, 2, 3, or 4, and m + n may be 4.

As specific examples, R ¹ may be a monovalent hydrocarbon group having 1 to 20 carbon atoms, R ² may be an alkoxy group having 1 to 20 carbon atoms, m may be 0, 1, 2, or 3, n may be 1, 2, 3, or 4, and m + n may be 4.

More specifically, in the above formula (1), R ¹ may be a monovalent hydrocarbon group having 1 to 10 carbon atoms, R ² may be an alkoxy group having 1 to 10 carbon atoms, m may be 0, 1, 2, or 3 , n can be 1, 2, 3, or 4, and m + n can be 4.

The 'monovalent hydrocarbon group' may be understood to include both monovalent saturated hydrocarbon groups and monovalent unsaturated hydrocarbon groups, and specific examples thereof include alkyl groups, alkenyl groups, alkynyl groups, cycloalkyl groups, aryl groups, alkylaryl groups, An alkyl group, and the like, all of which are monovalent atomic groups composed of carbon and hydrogen.

According to an embodiment of the present invention, the alkoxysilane compound may be at least one selected from the group consisting of methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, , Vinyltrimethoxysilane and vinyltriethoxysilane. In this case, the effect of further improving the dispersibility can be obtained.

The method for preparing a silica-based composite powder for ultraviolet shielding according to an embodiment of the present invention includes the steps of: (S1) preparing porous silica by emulsification; (S2) doping an inorganic ultraviolet screening agent on the inside surface of the pores of the porous silica prepared in the step (S1) to prepare a porous silica doped with an inorganic ultraviolet screening agent on the surface inside the pores; (S3) of impregnating porous silica doped with an inorganic UV-blocking agent on the surface of the pores produced in the step (S2), with an organic UV-blocking agent to prepare porous silica impregnated with an organic UV-blocking agent in the pores; And coating the outer surface of the porous silica impregnated with the organic UV blocking agent in the pores produced in the step (S3) (refer to FIG. 2).

The step (S1) is a step for preparing a porous silica which is a matrix of the silica-based composite powder, and is characterized by preparing a porous silica by emulsifying the silica-based precursor in a solvent. According to the present invention, when the step (S1) is carried out by emulsification, compared to a sol-gel method in which only silica particles having an average particle diameter in nm are prepared, The silica-based precursor can be easily obtained and the productivity is improved.

According to one embodiment of the present invention, the silica-based precursor may be a silicate metal salt capable of forming porous silica, or tetraalkoxysilane, and may be, for example, sodium silicate or tetraethoxysilane. In addition, the solvent may be a hydrocarbon-based solvent, and specific examples thereof include hydrocarbon-based oils such as kerosenes; And hydrocarbon-based organic solvents such as hexane, heptane, octane and the like. As another example, the solvent may be methylene chloride.

Wherein (S1) phase in a solvent, a silica-containing precursor and in the presence of an emulsifier, preparing a emulsion by the droplets (droplet) of the silica-based precursor formed in the solvent, the emulsion, and sodium hydrogen carbonate for the formation of the porous silica (NaHCO ₃ ) Aqueous solution (see Fig. 3). At this time, in the preparation of the emulsion, the solvent is mixed with the silica-based precursor solution having a concentration of 0.5 M to 1.5 M, 0.7 M to 1.3 M, or 0.9 M to 1.1 M at a volume ratio (silica-based precursor solution: solvent) of 1: 0.5 to 1.5, 1: 0.7 to 1.3, or 1: 0.9 to 1.1, and the emulsifier is a silica-based precursor solution 100 having a concentration of 0.5 M to 1.5 M, 0.7 M to 1.3 M, or 0.9 M to 1.1 M 0.1 to 10 parts by weight, 0.5 to 8 parts by weight, or 1 to 5 parts by weight based on 100 parts by weight of the emulsifier. The amount of the emulsifier to be added may be adjusted according to the size of the droplet, As the enemy size is small and the number of enemies is large, the amount of emulsifier can be increased. Also, the concentration of the sodium bicarbonate (NaHCO ₃ ) aqueous solution for forming the silica may be 1 M to 1.5 M, 1.1 M to 1.4 M, or 1.1 M to 1.3 M.

The liquid droplet is influenced by the emulsification rate during the preparation of the emulsion in which the droplet of the silica-based precursor is formed. The droplet size and number are different according to the emulsification rate. The faster the emulsification rate is, There is an effect that the smaller porous silica particles can be formed. As a specific example, the emulsification rate may be 7,500 rpm or more, 8,000 rpm or more, or 8,000 rpm to 10,000 rpm, and within this range, an average particle diameter of 1 탆 to 10 탆, 1 탆 to 8 탆, or 1 탆 to 5 탆 It is possible to produce a porous silica having an excellent wettability and feeling at the time of formulation of a composition containing the silica-based composite powder, and to have an effect of increasing the density of distribution per particle area at the time of coating.

When the emulsion is added to an aqueous solution of sodium hydrogencarbonate (NaHCO ₃ ) to form porous silica, the reaction is carried out at a temperature of 0 ° C to 60 ° C, 5 ° C to 55 ° C, or 10 ° C to 50 ° C Deg.] C, and the reaction may be carried out for from 1 hour to 8 hours, from 2 hours to 6 hours, or from 3 hours to 5 hours.

According to an embodiment of the present invention, the reaction temperature is a factor for determining the specific surface area, pore volume, and pore size of the porous silica. The lower the reaction temperature, the smaller the pore volume and the pore size, The higher the reaction temperature, the more the pore volume and the pore size increase but the specific surface area can be reduced and the effect of the pore volume, the pore size and the specific surface area is excellent in the range of the above reaction temperature (see FIG. 4 ).

According to an embodiment of the present invention, the porous silica produced by the step (S1) may have an average particle size of 1 to 10 mu m, 1 to 8 mu m, or 1 to 5 mu m, and a pore size of 10 nm or less, 1 nm to 10 nm, or 3 nm to 8 nm.

Meanwhile, the porous silica synthesized through the reaction can be obtained in the form of a solution, and the obtained porous silica solution can be mixed with oil / water as an emulsified state and be basic due to sodium hydrogencarbonate. According to an embodiment of the present invention, in order to obtain a porous silica powder from the porous silica solution, a nitric acid dilution solution containing 5 wt% to 30 wt% of nitric acid is mixed with the porous silica solution to prepare a porous silica solution Separating the oil and water, removing the separated oil layer, washing with alcohol and distilled water, filtering and drying, and from the steps, a porous silica powder can be obtained (See FIG. 3).

The step (S2) may be carried out by impregnating porous silica with a precursor of the inorganic ultraviolet screening agent, for impregnating the surface of the inside of the pores of the porous silica with an inorganic ultraviolet screening agent.

The precursor of the inorganic UV blocking agent may be a metal alkoxide, preferably titanium alkoxide. Specific examples thereof include titanium tetraisopropoxide, titanium titanium oxide ). In this case, the inorganic UV-blocking agent in the porous silica is easily doped and the UV-blocking index is excellent.

According to an embodiment of the present invention, the impregnation amount of the precursor of the inorganic UV blocking agent may be determined by the oil absorption amount of the porous silica. According to one embodiment of the present invention, the oil absorption amount of the porous silica is 0.5 cm ³ / 2.0 cm ³ / g, 0.7 cm ³ / g to 1.8 cm ³ / g, or 0.8 cm ³ / g to 1.5 cm ³ / g, wherein the impregnation amount of the precursor of the inorganic UV- 20 parts by weight to 120 parts by weight, 20 parts by weight to 80 parts by weight, or 40 parts by weight to 80 parts by weight with respect to the weight of the inorganic fine particles, and within this range, the inorganic ultraviolet blocking agent is uniformly doped to the inside surface of the pores of the porous silica . As another example, the conversion of the precursor of the inorganic UV blocking agent to the inorganic UV blocking agent may be 10 wt% to 50 wt%, 10 wt% to 40 wt%, or 20 wt% to 30 wt% %. ≪ / RTI >

On the other hand, the oil absorption amount of the porous silica was measured by dropping a small amount of liquid paraffin having an absolute viscosity of 25 cst to 35 cst into 1 g of the porous silica powder with a micropipette to measure the weight of paraffin which can maximally absorb pores present in silica , And the specific gravity of paramin (0.85 g / cm ³ ) divided by the weight of porous silica (1 g).

According to an embodiment of the present invention, the impregnation of the step (S2) may be carried out by adding a precursor of an inorganic UV-blocking agent to the porous silica powder prepared in the step (S1). As a specific example, The mixture is mixed with the pores so that the precursor of the inorganic ultraviolet screening agent is absorbed and then distilled water is added thereto and the mixture is heated at 50 to 100 캜, 60 캜 to 90 캜, or 70 캜 to 90 캜 for 1 hour to 8 hours, 3 hours to 5 hours. As described above, when the precursor of the inorganic UV-blocking agent is mixed with the pores of the porous silica and mixed with distilled water, the capillary phenomenon causes the precursor of the inorganic UV-blocking agent to flow into the pores of the mixed porous silica The distilled water is absorbed and thereby the dehydration condensation reaction between the hydroxyl group (-OH) existing on the surface inside the pores of the porous silica and the alkoxy group (-OR) of the metal alkoxide, which is the precursor of the inorganic ultraviolet screening agent, And may be doped with a metal oxide bonded to the inner surface.

The step (S3) may include a step of impregnating the inside of the pores of the porous silica with the organic ultraviolet screening agent, wherein the porous silica doped with the inorganic ultraviolet screening agent on the surface of the pores produced in the step (S2) And adding the organic UV-blocking agent to the dissolved alcohol and allowing the organic UV-blocking agent to be absorbed into the pores of the porous silica.

The alcohol is not particularly limited as long as it can dissolve the organic ultraviolet screening agent. By adding the porous silica to the alcohol in which the organic ultraviolet screening agent is dissolved, the alcohol is volatilized and removed by drying at room temperature without any additional reaction step , A porous silica impregnated with an organic ultraviolet blocking agent can be obtained.

On the other hand, the impregnation amount of the organic UV blocking agent can be determined by the oil absorption amount of the porous silica doped with the inorganic UV blocking agent on the surface of the inside of the pores produced in the step (S2), and according to an embodiment of the present invention, ³ / g to 1.5 cm ³ / g, 0.3 cm ³ / g to 1.2 cm ³ / g, or 0.5 cm ³ / g to 1.0 cm ³ / g.

The step (S4) is a step for obtaining a silica-based composite powder by coating the surface of porous silica doped with an inorganic ultraviolet screening agent and impregnated with an organic ultraviolet screening agent to prevent elution of the organic ultraviolet screening agent, The coating of step (S4) may be carried out using an alkoxysilane-based compound in the presence of a basic catalyst. When the step (S4) is not carried out, pores present on the surface of the porous silica cause the organic-based ultraviolet screening agent to dissolve in the oil or alcohol when it comes into contact with the oil or alcohol, and may be dissolved out to the outside of the porous silica. Accordingly, in the case where the outer surface of the porous silica is coated by the step (S4), the coating layer prevents the organic-based ultraviolet screening agent impregnated in the porous silica from contacting with the oil or alcohol, There is an effect that can be prevented.

According to an embodiment of the present invention, the step (S4) may be carried out by introducing the alkoxysilane compound in the presence of the porous silica impregnated with the organic UV-blocking agent in the pores produced in the step (S3) , The amount of the alkoxysilane compound to be added is 20 to 80 parts by weight, 30 to 70 parts by weight, or 40 to 60 parts by weight, based on 100 parts by weight of the porous silica impregnated with the organic UV- And the outer surface of the porous silica is uniformly coated within this range. On the other hand, the coating can be carried out for from 1 hour to 10 hours, from 2 hours to 8 hours, or from 3 hours to 6 hours, and is carried out at from 10 ° C to 90 ° C, from 20 ° C to 80 ° C, or from 30 ° C to 60 ° C .

As described above, when the silica-based composite powder is produced according to the steps (S1) to (S4) of the method for producing a silica-based composite powder of the present invention, particles of the porous silica Size, specific surface area, pore volume and pore size can be freely controlled, so that the amount of the ultraviolet shielding agent to be doped and impregnated in the pores can be appropriately controlled according to the application, and the silica-based composite powder for UV shielding can be easily There is an effect that can be provided. Further, by changing the kinds of the inorganic substances and the organic substances doped and impregnated in the pores of the silica-based composite powder for ultraviolet shielding, it is possible to provide a silica-based material which is suitable for use in other industrial fields, It is possible to produce a composite powder.

The composition according to an embodiment of the present invention may include the silica-based composite powder for ultraviolet shielding. The composition may be, for example, an ultraviolet screening agent used in cosmetics such as a sun cream and the like. As another example, the composition may be an ultraviolet screening clothing, a film or a resin composition. The ultraviolet screening silica- It can serve as a blocking additive.

In particular, when the composition is a resin composition, the composition includes the silica-based composite powder according to the present invention as an additive for blocking ultraviolet rays, so that durability and service life are improved even when exposed to ultraviolet rays for a long time, As shown in Fig.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood, however, that the following examples are illustrative of the present invention and that various changes and modifications can be made within the scope and spirit of the present invention, which are obvious to those of ordinary skill in the art and do not limit the scope of the present invention.

Example

Example 1

≪ Preparation of porous silica &

Kerosine was added in the same volume to 100 parts by weight of a 1M sodium silicate aqueous solution, Span 80 was added as an emulsifier to 2 And emulsified at an emulsification rate of 8,000 rpm using a homomixer to form an emulsion in which a sodium silicate droplet was formed. Thereafter, the above-mentioned emulsion was added to 100 parts by weight of a 1.2 M aqueous solution of sodium hydrogencarbonate, and the mixture was reacted at 10 DEG C for 4 hours to prepare a porous silica solution synthesized with porous silica. Thereafter, a nitric acid aqueous solution diluted with 30% by weight of nitric acid was added to the porous silica solution to neutralize the oil layer and the water layer, and then the separated oil layer was removed, washed with ethanol and distilled water, and filtered And then dried to obtain a porous silica powder.

<Doping with inorganic sunscreen>

To 100 parts by weight of the prepared porous silica powder, 60 parts by weight of titanium butoxide was added, and the titanium alkoxide was mixed with the pores of the porous silica so that the titanium alkoxide was absorbed. Then, distilled water was added thereto and reacted at 80 캜 for 4 hours, To prepare titanium dioxide-doped porous silica.

<Impregnation with organic sunscreen>

100 parts by weight of porous silica doped with titanium dioxide was mixed with 100 parts by weight of avobenzone 30 And ethanol was removed by drying at room temperature to thereby introduce titanium dioxide into the surface of the pores to form a porous silica impregnated with avobenzone .

&Lt; Preparation of silica composite powder &

Subsequently, 100 parts by weight of distilled water and 1 part by weight of ammonia water were put in a 2 L four-necked flask, 10 parts by weight of porous silica impregnated with titanium dioxide and doped with avobenzone was added to the prepared pore inner surface, Lt; / RTI &gt; Thereafter, the temperature was raised to 30 占 폚, and 5 parts by weight of methyltrimethoxysilane was added thereto. The mixture was reacted for 2 hours, then heated to 60 占 폚 and reacted for 2 hours to prepare a silica-based composite powder .

Example 2

Example 1 was carried out in the same manner as in Example 1, except that the reaction was carried out at 30 占 폚 after the emulsion injection into the porous silica.

Example 3

The procedure of Example 1 was repeated except that the reaction was carried out at 50 캜 after the emulsion was charged during the production of the porous silica.

Comparative Example 1

Example 1 was carried out in the same manner as in Example 1, except that 100 parts by weight of titanium butoxide was added when the inorganic ultraviolet screening agent was doped.

Experimental Example

Experimental Example 1

The specific surface area of the porous silica prepared in Examples 1 to 3 was measured by the following method. The pore volume and the pore size, as well as their values, are shown in Table 1 and FIG.

* Specific surface area (m ² / g): Based on the BET measurement method, the sample was pretreated at 200 ° C. for 2 hours, and then nitrogen (N ₂ ) was used as an adsorption gas, and a BET measuring instrument Micromeritics The specific surface area of the porous silica was measured with a Tristar (TM) 3000 instrument.

division Example One 2 3 Specific surface area (m ² / g) 645.74 602.08 435.18 Pore volume (cm ³ / g) 0.78 0.72 0.75 Pore size (nm) 4.85 4.81 6.93

As shown in Table 1 and FIG. 4, the pore volume and the pore size decrease as the reaction temperature is lowered according to the reaction temperature in the production of the porous silica, but the specific surface area increases. As the reaction temperature increases, , But the specific surface area tends to decrease.

Experimental Example 2

In the preparation of the silica-based composite powder in Example 1 and Comparative Example 1, titanium dioxide was doped depending on the impregnation amount of titanium butoxide when the inorganic ultraviolet screening agent was doped.

In the case of Example 1, it was confirmed that only titanium dioxide was doped into the pores of the porous silica. In Comparative Example 1, however, titanium butoxide was supplied to the inside of the pores of the porous silica, It was confirmed that titanium was doped.

The present inventors have found that when the silica-based composite powder is produced according to the present invention, the porous silica having a pore size of 10 nm or less can be produced, and the inorganic ultraviolet screening agent is doped into the pores of the prepared porous silica The particle size of the inorganic ultraviolet screening agent can be controlled to be small so that the transparency is increased and the surface area of the metal oxide particles capable of absorbing ultraviolet rays when using the inorganic ultraviolet screening agent equivalent to that of the inorganic ultraviolet screening agent added to the existing ultraviolet screening agent And it was confirmed that the ultraviolet ray shielding effect from the organic ultraviolet ray blocking agent impregnated inside the pores of the porous silica was markedly increased and the elution of the organic ultraviolet ray blocking agent from the coating layer could be prevented.

Claims (10)

delete delete delete delete delete (S1) preparing porous silica by emulsification;
(S2) doping an inorganic ultraviolet screening agent on the inside surface of the pores of the porous silica prepared in the step (S1) to prepare a porous silica doped with an inorganic ultraviolet screening agent on the surface inside the pores;
(S3) of impregnating porous silica doped with an inorganic UV-blocking agent on the surface of the pores produced in the step (S2), with an organic UV-blocking agent to prepare porous silica impregnated with an organic UV-blocking agent in the pores; And
(S4) coating the outer surface of the porous silica impregnated with the organic UV-blocking agent in the pores produced in the step (S3)
The step (S1)
Preparing an emulsion in which a silica-based precursor droplet is formed in a solvent by using a silica-based precursor and an emulsifier;
Introducing the emulsion into an aqueous sodium hydrogen carbonate solution to prepare porous silica,
The average particle diameter of the porous silica is 1 탆 to 10 탆,
Oil absorption of the porous silica production method for a silica-based composite powder for UV protection, characterized in that 0.5 cm ³ / g to 2.0 cm ³ / g The method according to claim 6,
Wherein the step (S1) is carried out at a reaction temperature of 0 ° C to 60 ° C. The method according to claim 6,
Wherein the doping in the step (S2) is carried out by impregnation. The method according to claim 6,
Wherein the coating of step (S4) is carried out using an alkoxysilane compound in the presence of a basic catalyst. delete

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