JP5103906B2 - Porous silica fine particles and method for producing the same - Google Patents

Description

  The present invention relates to porous silica fine particles and a method for producing the same. In particular, the present invention relates to porous silica fine particles used for a low refractive index film or the like of an antireflection film and a method for producing the same.

  Currently, with the development of multimedia, various developments have been seen in various display devices (display devices). Among various types of display devices, especially those used outdoors, mainly for portable use, the improvement in visibility has become increasingly important, and even in large display devices, it is easier to see. This is a technical issue as it is required by consumers.

  Conventionally, as one means for improving the visibility of a display device, an antireflection film made of a low refractive index material is coated on a substrate of the display device, and a method of forming the antireflection film For example, a method of forming a fluorine compound thin film by a vapor deposition method is known. However, in recent years, there has been a demand for a technique capable of forming an antireflection film for a large display device at a low cost centering on a liquid crystal display device. However, in the case of the vapor deposition method, it is difficult to form a high-efficiency and uniform antireflection film on a large-area substrate, and a vacuum apparatus is required, so that the cost can be reduced. Have difficulty.

  Under such circumstances, a method of forming an antireflection film by preparing a liquid composition by dissolving a material having a low refractive index in an organic solvent and applying it to the surface of a substrate has been studied. Specific materials constituting such a low refractive index layer include fluorine-containing organic materials, low refractive index fine particles, and the like, and these materials have been proposed to be used alone or in combination.

Examples of the low refractive index fine particles include silica particles. Silica particle production methods include polycondensation of alkoxysilane in an organic solvent (Patent Document 1), and decoration of other inorganic compounds and organosilicon compounds on SiO ₂ particles (Patent Document 2 and Patent Document 3). Etc. are known. Further, as a film containing silica particles, a film containing silica particles and a matrix (Patent Document 4), a film in which fine particles such as SiO ₂ having a particle diameter of 100 to 150 nm are dispersed (Patent Document 5), and an organosilicon compound A membrane (Patent Document 6) to which silica hollow particles are added is known.
Japanese Patent Laid-Open No. 4-50112 JP 2001-233611 A JP 7-10522 A JP 2001167676 A Japanese Patent Laid-Open No. 5-13021 JP 2002-317152 A

However, when silica particles are used in the low refractive index film, if the average particle size is large, visible light scattering may occur, the light transmittance may decrease, and the luminance of the display device may decrease, and the specific surface area may be small. There was a problem that the refractive index was difficult to decrease.
Accordingly, an object of the present invention is to provide a porous silica fine particle having a fine average particle diameter and a method for producing the same. Another object of the present invention is to provide polycrystalline silica fine particles having excellent water resistance and a method for producing the same.

According to the present invention, the following porous silica fine particles and a method for producing the same are provided.
1. Porous silica fine particles comprising a silicon compound represented by the following formula (1) and a hydrolyzate and / or hydrolysis condensate of the silicon compound represented by the following formula (2) and having an average particle diameter of 5 to 50 nm .
R ¹ _m SiX _4-m (1)
R ² _n SiX _4-n (2)
(R ¹ is an alkyl group having 1 to 8 carbon atoms, X is independently an alkoxy group having 1 to 4 carbon atoms, a halogeno group, an isocyanate group (—N═C═O), a carboxyl group, or a carbon group having 2 to 4 carbon atoms. alkyloxy carboxyl group or alkylamino group having 1 to 4 carbon atoms, m is an integer of 0 to 1 .R ² is alkenyl group having 2 to 8 carbon atoms, acryloxyalkyl group or a carbon number of 4 to 8 carbon atoms A methacryloxyalkyl group of 5 to 8, n represents an integer of 1 to 3. X in formula (1) and X in formula (2) may be the same or different)
2. When the total of the silicon compound represented by Formula (1) and the silicon compound represented by Formula (2) is 100 mol%, the hydrolyzate and / or hydrolysis condensate is represented by Formula (1). 2. The porous silica fine particle according to 1 above, which is a reaction product of 70 to 99 mol% of a silicon compound and 30 to 1 mol% of a silicon compound represented by the formula (2).
3. It consists of a silicon compound represented by the following formula (1), a silicon compound represented by the following formula (2) and a hydrolyzate and / or hydrolysis condensate of the silicon compound represented by the following formula (3), Porous silica fine particles having a particle size of 5 to 50 nm.
R ¹ _m SiX _4-m (1)
R ² _n SiX _4-n (2)
R ³ _p SiX _4-p (3)
(R ¹ is an alkyl group having 1 to 8 carbon atoms, X is independently an alkoxy group having 1 to 4 carbon atoms, a halogeno group, an isocyanate group (—N═C═O), a carboxyl group, or a carbon group having 2 to 4 carbon atoms. alkyloxy carboxyl group or alkylamino group having 1 to 4 carbon atoms, m is an integer of 0 to 1 .R ² is alkenyl group having 2 to 8 carbon atoms, acryloxyalkyl group or a carbon number of 4 to 8 carbon atoms A methacryloxyalkyl group of 5 to 8, n represents an integer of 1 to ^3. R ³ represents a fluorine-substituted alkyl group having 1 to 12 carbon atoms, and p represents an integer of 1 to ^{3. In} the formula (1), X, X in formula (2) and X in formula (3) may be the same or different)
4). When the total of the silicon compound represented by the formula (1), the silicon compound represented by the formula (2) and the silicon compound represented by the formula (3) is 100 mol%, the hydrolyzate and / or hydrolyzate The decomposition condensate is 60 to 98 mol% of a silicon compound represented by the formula (1), 1 to 30 mol% of a silicon compound represented by the formula (2), and 1 to 20 silicon compounds represented by the formula (3). 4. The porous silica fine particles according to 3 above, which is a mol% reactant.
5. The porous silica fine particle according to any one of 1 to 4 above, wherein m is 0 in the silicon compound represented by the formula (1).
6). The silicon compound represented by the formula (1) and the silicon compound represented by the formula (2) are obtained from water, an alcohol having 1 to 3 carbon atoms, a basic compound, and a half ether of acid amide, diol and diol. 5. The method for producing porous silica fine particles according to any one of the above 1, 2 and 4, which is hydrolytically condensed in the presence of at least one selected.
7). 7. The method for producing porous silica fine particles according to 6 above, wherein the silicon compound represented by the formula (1) is hydrolytically condensed, and then the silicon compound represented by the formula (2) is added and further hydrolytically condensed.
8). The silicon compound represented by the formula (1), the silicon compound represented by the formula (2), and the silicon compound represented by the formula (3) are mixed with water, an alcohol having 1 to 3 carbon atoms, and a basic compound. And the method for producing porous silica fine particles according to any one of 3 to 5 above, wherein the hydrolytic condensation is carried out in the presence of at least one selected from acid amides, diols, and half ethers of diols.
9. 9. Production of porous silica fine particles according to 8 above, wherein the silicon compound represented by formula (1) is hydrolytically condensed, and then the silicon compound represented by formula (2) and formula (3) is added to further hydrolytically condense. Method.
10. The silicon compound represented by the following formula (4) is hydrolyzed in the presence of at least one selected from water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols, and half ethers of diols. After the condensation, a silicon compound represented by the following formula (5) and / or a silicon compound represented by the following formula (6) is added to cause hydrolytic condensation, and the average particle size is 5 A method for producing porous silica fine particles of ˜50 nm.
SiX ₄ (4)
R ⁴ _p SiX _4-p (5)
R ⁵ _q SiX _4-q (6)
(R ⁴ is an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an acryloxyalkyl group having 4 to 8 carbon atoms or a methacryloxyalkyl group having 5 to 8 carbon atoms, and X is independently carbon. An alkoxy group having 1 to 4 carbon atoms, a halogeno group, an isocyanate group (—N═C═O), a carboxyl group, an alkyloxycarbonyl group having 2 to 4 carbon atoms or an alkylamino group having 1 to 4 carbon atoms, p is 1 to R represents an integer of 3. R ⁵ represents a fluorine-containing alkyl group having 1 to 12 carbon atoms, q represents an integer of 1 to 3. X in Formula (4), X in Formula (5), and Formula (6) X may be the same or different)
11. The silicon compound represented by the formula (4) is hydrolyzed and condensed under reaction conditions of 20 to 100 ° C. for 1 to 12 hours, and further the silicon compound and / or the formula (6) represented by the formula (5). 11. The method for producing porous silica fine particles according to 10 above, wherein the silicon compound represented by the formula (1) is added and hydrolytic condensation is carried out at 20 to 100 ° C. under reaction conditions for 0.5 to 12 hours.
12 In the presence of at least one selected from water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols and half ethers of diols, silicon compounds represented by the following formula (4), and the following formulas: After hydrolytic condensation of the silicon compound represented by (5) and / or the silicon compound represented by formula (6), an aprotic organic solvent and pure water or an aqueous acid solution are added, and the aprotic organic solvent is added. A method for producing porous silica fine particles having an average particle diameter of 5 to 50 nm, wherein porous silica particles are extracted into a layer.
SiX ₄ (4)
R ⁴ _p SiX _4-p (5)
R ⁵ _q SiX _4-q (6)
(R ⁴ is an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an acryloxyalkyl group having 4 to 8 carbon atoms or a methacryloxyalkyl group having 5 to 8 carbon atoms, and X is independently carbon. An alkoxy group having 1 to 4 carbon atoms, a halogeno group, an isocyanate group (—N═C═O), a carboxyl group, an alkoxycarbonyl group having 2 to 4 carbon atoms or an alkylamino group having 1 to 4 carbon atoms, p is 1 to 3 R ⁵ represents a fluorine-containing alkyl group having 1 to 12 carbon atoms, q represents an integer of 1 to 3. X in Formula (4), X in Formula (5), and Formula (6) X may be the same or different)
13. The silicon compound represented by the formula (4), wherein the sum of the silicon compound represented by the formula (4), the silicon compound represented by the formula (5) and the silicon compound represented by the formula (6) is 100 mol%. The method for producing porous silica fine particles according to any one of 10 to 12 above, wherein the hydrolytic condensation is carried out at a ratio of 70 to 99 mol%.
14 The total concentration of the silicon compound represented by formula (4), the silicon compound represented by formula (5) and the silicon compound represented by formula (6) in the reaction solution is 0.5 to 10% by mass. 4. The method for producing porous silica fine particles according to any one of 1 to 3 above, wherein
15. The porous material according to any one of 12 to 14 above, wherein the aprotic organic solvent is at least one selected from the group consisting of ester solvents, ether solvents, ketone solvents and hydrocarbon solvents. A method for producing silica fine particles.
16. 16. The method for producing porous silica fine particles according to any one of 12 to 15, wherein the acid in the acid aqueous solution is a protonic acid.
17. The ratio of reaction liquid / aprotic organic solvent / pure water or aqueous acid solution is 1 / 0.2 to 2 / 0.1 to 2 (mass ratio), any one of 12 to 16 above Of producing porous silica particles.
18. The method for producing porous silica particles according to any one of 12 to 17 above, wherein the aprotic organic solvent layer is concentrated after the extraction.
19. 19. The method for producing porous silica particles according to 18 above, wherein an organic solvent having a boiling point higher than that of the aprotic organic solvent is added when the aprotic organic solvent layer is concentrated.
20. A porous silica fine particle obtained by the production method according to any one of 10 to 19 above.
21. 21. A curable composition comprising the polycrystalline silica fine particles according to any one of 1 to 5 and 20 and an organic solvent.
22. 21. An antireflection film comprising a low refractive index layer containing the polycrystalline silica fine particles according to any one of 1 to 5 and 20 above.

  According to the present invention, porous silica fine particles having a fine average particle diameter and a method for producing the same can be provided. According to the present invention, it is possible to provide polycrystalline silica fine particles having excellent water resistance and a method for producing the same.

It is sectional drawing concerning one Embodiment of the anti-reflective film of this invention.

  Hereinafter, the present invention will be described in detail for each embodiment.

I. First and Second Aspects The polycrystalline silica fine particles according to the first aspect of the present invention include a silicon compound represented by the following formula (1) and a hydrolyzate of the silicon compound represented by the following formula (2) and / or Or it consists of a hydrolysis-condensation product, The average particle diameter is 5-50 nm, By hydrolytic condensation of the silicon compound represented by following formula (1) and the silicon compound represented by following formula (2), can get.
R ¹ _m SiX _4-m (1)
R ² _n SiX _4-n (2)

The polycrystalline silica fine particles of the second aspect of the present invention are composed of a silicon compound represented by the following formula (1), a silicon compound represented by the following formula (2), and a silicon compound represented by the following formula (3). A silicon compound represented by the following formula (1) and a silicon compound represented by the following formula (2), comprising a hydrolyzate and / or a hydrolysis condensate and having an average particle diameter of 5 to 50 nm. And obtained by hydrolytic condensation of a silicon compound represented by the following formula (3).
R ¹ _m SiX _4-m (1)
R ² _n SiX _4-n (2)
R ³ _p SiX _4-p (3)

In Formula (1), R ¹ is an alkyl group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group, an ethyl group, or a propyl group.
In the formulas (1), (2) and (3), a plurality of X which may exist are each independently an alkoxy group having 1 to 4 carbon atoms, a halogeno group (halogen atom), an isocyanate group, a carboxyl group, or 2 to 2 carbon atoms. 4 alkyloxycarbonyl group or C1-C4 alkylamino group, Preferably it is a C1-C4 alkoxy group and a halogeno group, More preferably, it is a C1-C4 alkoxy group.
Moreover, X in each formula (1), (2) and (3) may be mutually the same, or may be different.
In formula (1), m is an integer of 0 to 1, preferably 0.
Examples of the compound represented by the formula (1) include tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, tetrachlorosilane, methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrichlorosilane, and ethyltrimethoxy. Examples include silane and ethyltriethoxysilane.
In the formula (2), R ² is an alkenyl group having 2 to 8 carbon atoms, an acryloxyalkyl group having 4 to 8 carbon atoms or a methacryloxyalkyl group having 5 to 8 carbon atoms, preferably a vinyl group, an allyl group, An acryloxyethyl group, an acryloxypropyl group, an acryloxybutyl group, a methacryloxyethyl group, a methacryloxypropyl group, and a methacryloxybutyl group.
In Formula (2), n is an integer of 1-3, Preferably it is 1-2.
Examples of the compound represented by the formula (2) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, acryloxypropyltrimethoxysilane, methacryloxypropyltrimethoxysilane, and the like.
In formula (3), R ³ is a fluorine-substituted alkyl group having 1 to 12 carbon atoms, preferably a fluorine-substituted alkyl group having 3 to 12 carbon atoms, more preferably a fluorine-substituted alkyl group having 3 to 10 carbon atoms. It is.
In Formula (3), p is an integer of 1-3, Preferably it is 1-2.
Examples of the compound represented by the formula (3) include 3,3,3-trifluoropropyltrimethoxysilane, 2-perfluorohexylmethyltrimethoxysilane, 2-perfluorohexylethyltrimethoxysilane, and 2-par. Examples include fluorooctylethyltrimethoxysilane, 2-perfluorooctylethyltriethoxysilane, and 3,3-di (trifluoromethyl) -3-fluoropropyltriethoxysilane.
In addition, you may use 2 or more types respectively of the silicon compound represented by Formula (1), the silicon compound represented by Formula (2), and the silicon compound represented by Formula (3).

  In the first aspect of the present invention, when the total of the silicon compound represented by the formula (1) and the silicon compound represented by the formula (3) is 100 mol%, the silicon represented by the formula (1) The silicon compound represented by the compound / formula (2) is preferably hydrolyzed and condensed at a ratio of 70 to 99/1 to 30 (molar ratio), more preferably 80 to 97/3 to 20 (molar ratio). The

  In the second aspect of the present invention, the total of the silicon compound represented by the formula (1), the silicon compound represented by the formula (2) and the silicon compound represented by the formula (3) is 100 mol%. The silicon compound represented by the formula (1) / the silicon compound represented by the formula (2) / the silicon compound represented by the formula (3) is preferably 60 to 98/1 to 30/1 to 20 (Mol%), more preferably hydrolytic condensation at a ratio of 65 to 96/2 to 20/2 to 15 (mol%).

The porous silica fine particles of the first and second aspects of the present invention can be photocured by having an alkenyl group, an acryloxyalkyl group or a carbon methacryloxyalkyl group.
Moreover, the porous silica fine particle of the 2nd aspect of this invention is excellent in the stain resistance at the time of making it a coating film by including a fluoroalkyl group.

The porous silica fine particles of the first and second aspects of the present invention have an average particle size of 5 to 50 nm, preferably 5 to 45 nm, and more preferably 5 to 40 nm. The average particle diameter is a number average particle diameter, and is measured by a transmission electron microscope observation image. The term “porous” as used in the present invention means that the specific surface area is 50 to 1000 m ² / g, preferably 50 to 800 m ² / g, more preferably 100 to 800 m ² / g. means. The specific surface area is measured by the BET method.
When the average particle size is within the above range, scattering of the obtained coating film in the visible light region can be suppressed. Further, due to being porous, the density is lowered, and the refractive index of the film containing such porous silica fine particles is lowered.

The porous silica fine particles having an average particle diameter and a specific surface area as in the present invention can be obtained by the production method described below.
In the presence of at least one selected from the group consisting of water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols, and half ethers of diols, the porous silica fine particles according to the first aspect of the present invention are It can be produced by hydrolytic condensation of the silicon compound represented by the formula (1) and the silicon compound represented by the above formula (2).
The porous silica fine particles of the second aspect of the present invention are present in the presence of at least one selected from water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols, and semi-ethers of diols. The silicon compound represented by the above formula (1), the silicon compound represented by the above formula (2) and the silicon compound represented by the above formula (3) can be produced by hydrolysis condensation.

Examples of basic compounds include amine compounds. Specific examples include pyridine, pyrrole, piperazine, pyrrolidine, piperidine, picoline, monoethanolamine, diethanolamine, dimethylmonoethanolamine, monomethyldiethanolamine, triethanolamine, diazabicyclooctane. , Diazabicyclononane, diazabicycloundecene, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, ammonia, methylamine, ethylamine, propylamine, butylamine, N, N-dimethylamine, N, N-diethylamine, N, N-dipropylamine, N, N-dibutyla Down, it can be mentioned trimethylamine, triethylamine, tripropylamine, tributylamine and the like. Preferably, ammonia, ethanolamine, tetramethylamine hydroxide and the like are used.
These basic compounds may be used alone or in combination of two or more.

The acid amide, diol or diol half ether is preferably compatible with water and alcohol.
As the acid amide, for example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and the like are used, and preferably N, N-dimethylformamide and N, N-dimethylacetamide are used.

As the diol, for example, ethylene glycol, propylene glycol, 1,2-butanediol and the like are used, and preferably ethylene glycol and propylene glycol are used.
As the diol half ether, for example, ethylene glycol monomethyl ether or propylene glycol monomethyl ether is used.
In the present invention, the particles can be made porous by the coexistence of acid amide, diol or diol half ether during the synthesis of the porous silica fine particles.

  The total concentration of the silicon compounds of formula (1) and formula (2) in the reaction solution in the first aspect of the present invention, or the total of the silicon compounds of formulas (1) to (3) in the second aspect of the present invention A density | concentration is 0.5-10 mass% normally in conversion of a complete hydrolysis condensate, Preferably it is 1-8 mass%. Here, “in terms of complete hydrolysis condensate” is a theoretical value calculated on the assumption that the silicon compound has been completely hydrolyzed and condensed, and X of the silicon compound of formula (1) and formula (2), or This corresponds to the mass in the case where X in the silicon compounds of the formulas (1) to (3) is substituted with ½ mol of oxygen atoms. By making the concentration of the silicon compound at the time of particle synthesis in the above range, coarsening of the particles can be prevented and fine particles having an average particle diameter of 5 to 50 nm can be obtained.

In the presence of at least one selected from the group consisting of water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols, and half ethers of diols, the polycrystalline silica fine particles according to the first aspect of the present invention are the above. It can be produced by hydrolytic condensation of the silicon compound represented by the formula (1) and the silicon compound represented by the above formula (2).
In the production of the polycrystalline silica fine particles of the second aspect of the present invention, at least one kind selected from water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols and diol half ethers. In the presence of a half ether compound, the silicon compounds represented by formula (1), formula (2) and formula (3) may be simultaneously mixed and hydrolytically condensed, or represented by formula (1). The silicon compound may be hydrolyzed and condensed, and then the silicon compounds represented by the formulas (2) and (3) may be added for further hydrolytic condensation.

In the first and second embodiments of the present invention, the hydrolysis condensation reaction temperature can be arbitrarily determined in consideration of the boiling point and reaction time of the alcohol and acid amide to be used. The reaction time depends on the type of silicon compound represented by formula (1) and formula (2), or formula (1), formula (2) and formula (3), reaction rate, type and amount of base, etc. The optimum value is of a changing nature and is not limited.
A curable composition in which porous silica particles are dispersed in an organic solvent by adding an organic solvent to the obtained hydrolysis-condensation reaction liquid and further removing unnecessary components by a method such as distillation or liquid-liquid extraction as necessary. You can get things.

  In this curable composition, the porous silica fine particles of the first or second aspect of the present invention are uniformly dispersed in an organic solvent. As an organic solvent, a C1-C8 alcohol type | system | group, a C3-C10 ketone type | system | group, and a C3-C10 ester type organic solvent can be used. The porous silica fine particles are dispersed in an organic solvent at a concentration of preferably 0.5 to 30% by mass.

  The curable composition of the first or second aspect of the present invention containing the porous silica fine particles of the first or second aspect of the present invention and an organic solvent is suitable as a composition for forming a low refractive index film. Can be used for In addition, the composition preferably includes a radical generator. Examples of the radical generator include a compound that thermally generates active radical species (thermal polymerization initiator) and a compound that generates active radical species by radiation (light) irradiation (radiation (light) polymerization initiator). Can be mentioned.

  The radiation (photo) polymerization initiator is not particularly limited as long as it can be decomposed by light irradiation to generate radicals to initiate polymerization. For example, acetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2 , 2-dimethoxy-1,2-diphenylethane-1-one, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, 4,4′-diaminobenzophenone, benzoin propyl ether, benzoin ethyl ether, benzyl dimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy Roxy-2-methyl-1-phenylpropan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane -1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, oligo (2-hydroxy-2-methyl-1- (4- (1-methylvinyl) phenyl) propanone) .

  As a commercial item of a radiation (photo) polymerization initiator, for example, Ciba Specialty Chemicals Co., Ltd. trade name: Irgacure 184, 369, 379, 651, 500, 819, 907, 784, 2959, CGI 1700, CGI 1750, CGI1850, CG24-61, Darocur 1116, 1173, manufactured by BASF, Inc. Product name: Lucillin TPO, manufactured by UCB, Inc. Product name: Ubekril P36, manufactured by Fratteri Lamberti, Inc. Product names: Ezacure KIP150, KIP65LT, KIP100F, KT37, KT55, KTO46 , KIP75 / B and the like.

  In the first and second embodiments, the blending amount of the organic solvent and the radical generator can be adjusted as appropriate. The organic solvent is usually 500 to 10,000 parts by mass with respect to 100 parts by mass of the porous silica particles, and the radical generator is The amount is usually 1 to 10 parts by mass with respect to 100 parts by mass of the porous silica fine particles.

  The curable composition of the first and second embodiments includes, as other components, a photosensitizer, a polymerization inhibitor, a polymerization initiation assistant, a leveling agent, a wettability improver, a surfactant, a plasticizer, and an ultraviolet absorber. Agents, antioxidants, antistatic agents, inorganic fillers, organic fillers, pigments, dyes and the like.

The curable compositions of the first and second embodiments are cured when fired or irradiated with ultraviolet rays and / or electron beams. For example, an optical low-refractive-index film can be formed by applying the composition to a substrate, drying, and firing or irradiating with ultraviolet rays and / or electron beams. The drying conditions are usually 40 to 150 ° C. and 0.5 to 30 minutes. In the case of firing, the curing conditions are usually heated at 150 to 500 ° C. for 1 to 120 minutes. In the case of ultraviolet rays, it is usually 50 to 3000 mJ / cm ² under anaerobic conditions, and in the case of an electron beam, it is 0.1 to 100 Mrad.

  As the substrate, a substrate used for a known antireflection film or the like can be used. For example, triacetyl cellulose, polyethylene terephthalate resin (Lumirror etc. manufactured by Toray Industries, Inc.), glass, polycarbonate resin, acrylic resin, styryl resin, arylate resin, norbornene resin (Arton manufactured by JSR Corporation, manufactured by Nippon Zeon Co., Ltd.) ZEONEX etc.), various transparent plastic plates such as methyl methacrylate / styrene copolymer resin, polyolefin resin, and films. Preferable examples include triacetyl cellulose, polyethylene terephthalate resin (Lumilar manufactured by Toray Industries, Inc.) and norbornene resin (Arton manufactured by JSR Co., Ltd.).

The antireflective film is a film in which a low refractive index film is formed on a substrate, but the low refractive index film containing the porous silica fine particles of the present invention has a low refractive index, and therefore can be suitably used as an antireflective film. . In the antireflection film, a low refractive index film, a high refractive index film, a medium refractive index film, a hard coat layer, an antistatic layer, and the like can be laminated on the substrate.
FIG. 1 shows an antireflection film 10 showing an embodiment of the present invention. As shown in FIG. 1, a hard coat layer 14 and a low refractive index layer 16 are laminated on a substrate 12.
Further, a high refractive index layer (not shown) may be further provided between the hard coat layer 14 and the low refractive index layer 16.
Further, an antistatic layer (not shown) may be further provided between the base material 12 and the hard coat layer 14, or directly on the antistatic layer without forming the hard coat layer 14. The low refractive index layer 16 may be formed.
In addition to the above layer structure, the antireflection film of the first or second aspect of the present invention is known as long as it includes the low refractive index layer 16 containing the polycrystalline silica fine particles of the first or second aspect of the present invention. Any layer structure may be adopted.

The porous silica fine particle according to the first or second aspect of the present invention is, for example, a temperature at which a liquid dispersion of silica particles obtained by the production method described above is vacuum-dried, and more preferably organic matter can be removed. It can also be obtained as a powder by treating at a temperature of ℃ or higher.
The porous silica fine particles according to the first and second aspects of the present invention are not limited to the optical applications described above, but include adsorbents, various column fillers, lubricants, paints, resins, rubber and paper fillers, and modifications. It can be used for preparations, cosmetics and the like.

II. 3rd aspect The manufacturing method of the porous silica fine particle of the 3rd aspect of this invention makes water, a C1-C3 alcohol, a basic compound, and an acid the silicon compound represented by following formula (4). After hydrolytic condensation in the presence of at least one selected from amides, diols, and half ethers of diols, the silicon compounds represented by the following formula (5) and / or the following formula (6) It is characterized by adding and hydrolyzing and condensing a silicon compound, and the average particle size of the obtained polycrystalline silica fine particles is 5 to 50 nm.
SiX ₄ (4)
R ⁴ _p SiX _4-p (5)
R ⁵ _q SiX _4-q (6)

  The porous silica particles obtained from only the tetrafunctional silane compound have poor water resistance (easy to absorb moisture) because silanolic hydroxyl groups remain. In the 3rd aspect of this invention, a residual hydroxyl group reduces by co-condensing with 1-3 functional silicon compound, and water resistance improves.

In formulas (4) to (6), a plurality of X which may be present independently represent an alkoxy group having 1 to 4 carbon atoms, a halogeno group (halogen atom), an isocyanate group, a carboxyl group, or an alkyloxy group having 2 to 4 carbon atoms. It is a carbonyl group or an alkylamino group having 1 to 4 carbon atoms, preferably an alkoxy group having 1 to 4 carbon atoms or a halogeno group, and more preferably an alkoxy group having 1 to 4 carbon atoms.
Moreover, X in each formula (4), (5) and (6) may be mutually the same, or may be different.
Examples of the compound represented by the formula (4) include tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, and tetrachlorosilane.

In formula (5), R ⁴ is an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an acryloxyalkyl group having 4 to 8 carbon atoms, or a methacryloxyalkyl group having 5 to 8 carbon atoms. Preferably an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, an acryloxyalkyl group having 5 to 8 carbon atoms, and a methacryloxyalkyl group having 6 to 8 carbon atoms, more preferably a methyl group. Ethyl group, propyl group, vinyl group, allyl group, acryloxyethyl group, acryloxypropyl group, acryloxybutyl group, methacryloxyethyl group, methacryloxypropyl group, methacryloxybutyl group.
In Formula (5), p is an integer of 1-3, Preferably it is 1-2.
Examples of the compound represented by the formula (5) include methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrichlorosilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxy. Examples include silane, vinyltrichlorosilane, acryloxypropyltrimethoxysilane, and methacryloxypropyltrimethoxysilane.

In formula (6), R ⁵ is a fluorine-substituted alkyl group having 1 to 12 carbon atoms, preferably a fluorine-substituted alkyl group having 3 to 12 carbon atoms, more preferably a fluorine-substituted alkyl group having 3 to 10 carbon atoms. It is.
In Formula (6), q is an integer of 1-3, Preferably it is 1-2.
Examples of the compound represented by the formula (6) include 3,3,3-trifluoropropyltrimethoxysilane, 2-perfluorohexylmethyltrimethoxysilane, 2-perfluorohexylethyltrimethoxysilane, and 2-par. Examples include fluorooctylethyltrimethoxysilane, 2-perfluorooctylethyltriethoxysilane, and 3,3-di (trifluoromethyl) -3-fluoropropyltriethoxysilane.
In addition, you may use 2 or more types of silicon compounds represented by Formula (4), the silicon compound represented by Formula (5), and the silicon compound represented by Formula (6), respectively.

  The reaction temperature and reaction time for hydrolysis condensation and cocondensation can be appropriately determined in consideration of the type, amount, and the like of the alcohol, basic compound, acid amide, silicon compound and the like to be used. However, usually, the silicon compound represented by the formula (4) is hydrolyzed and condensed under reaction conditions of 20 to 100 ° C. for 1 to 12 hours, preferably 20 to 80 ° C. for 1 to 10 hours. Moreover, the silicon compound represented by the formula (5) and / or (6) is usually used at 20 ° C to 100 ° C for 0.5 to 12 hours, preferably 20 ° C to 80 ° C for 0.5 to 8 hours. Co-condensation under reaction conditions.

  In the production method of the third aspect of the present invention, the total amount of silicon compounds represented by formulas (4) to (6) is 100 mol%, and the silicon compound of formula (4) is preferably 70 to 99 mols. %, More preferably 75 to 97 mol%.

Examples of the basic compound used in the production method of the third aspect of the present invention include the compounds exemplified in the first and second aspects of the present invention.
These basic compounds may be used alone or in combination of two or more.

The acid amide, diol or diol half ether is preferably compatible with water and alcohol.
Examples of the acid amide include the compounds exemplified in the first and second aspects of the present invention.

Examples of the diol and the half ether of the diol include the compounds exemplified in the first and second embodiments of the present invention.
In the present invention, the particles can be made porous by the coexistence of acid amide, diol or diol half ether during the synthesis of the porous silica fine particles.

  The total concentration of the silicon compounds represented by the formulas (4) to (6) in the reaction solution is usually 0.5 to 10% by mass, preferably 1 to 8% by mass in terms of complete hydrolysis condensate. Here, “in terms of complete hydrolysis condensate” is a theoretical value calculated on the assumption that the silicon compound has been completely hydrolyzed and condensed, and X of the silicon compound of formulas (4) to (6) is This corresponds to the mass when X is substituted by 1/2 mole of oxygen atom of X. By setting the concentration of the silicon compound at the time of particle synthesis within the above range, particle coarsening can be prevented and fine particles having an average particle diameter of 5 to 50 nm can be obtained.

According to the production method of the third aspect of the present invention, porous silica fine particles having an average particle diameter of 5 to 50 nm can be obtained. Preferably, the average particle size is 5 to 45 nm, more preferably 5 to 40 nm. The average particle diameter is a number average particle diameter, and is measured by a transmission electron microscope observation image. The term “porous” as used in the present invention means that the specific surface area is 50 to 1000 m ² / g, preferably 50 to 800 m ² / g, more preferably 100 to 800 m ² / g. means. The specific surface area is measured by the BET method.
When the average particle diameter is in the above range, scattering in the visible light region of the obtained coating film can be suppressed. Further, due to being porous, the density is lowered, and the refractive index of the film containing such porous silica fine particles is lowered.

The curable composition of the third aspect of the present invention is obtained by dispersing the porous silica fine particles obtained by the production method of the third aspect of the present invention in an organic solvent. As an organic solvent, a C1-C8 alcohol type | system | group, a C3-C10 ketone type | system | group, and a C3-C10 ester type organic solvent can be used. The porous silica fine particles are dispersed in an organic solvent at a concentration of preferably 0.5 to 30% by mass.
The curable composition of the third aspect is in the presence of water, an alcohol having 1 to 3 carbon atoms, a basic compound, and at least one half ether compound selected from acid amides, diols and half ethers of diols, After hydrolytic condensation of the silicon compounds represented by formula (4), formula (5) and formula (6), an organic solvent is added if necessary, and further unnecessary components are distilled or liquid-liquid extracted if necessary. It can manufacture by removing by methods, such as.

  The curable composition containing the porous silica fine particles and the organic solvent according to the third aspect of the present invention can be suitably used as a composition for forming a low refractive index film. In addition, the composition preferably includes a radical generator. Examples of the radical generator include a compound that thermally generates active radical species (thermal polymerization initiator) and a compound that generates active radical species by radiation (light) irradiation (radiation (light) polymerization initiator). Can be mentioned.

  As a commercial item of a radiation (photo) polymerization initiator and a radiation (photo) polymerization initiator, what was illustrated in description of the 1st and 2nd aspect of this invention can be mentioned.

  The blending amount of the porous silica fine particles and the radical generator in the third aspect of the present invention can be adjusted as appropriate, but the porous silica fine particles are usually 1 to 20 parts by mass with respect to 100 parts by mass of the organic solvent. Usually, it is 1 to 10 parts by mass with respect to 100 parts by mass of the porous silica fine particles.

  The curable composition of the third aspect of the present invention includes, as other components, a photosensitizer, a polymerization inhibitor, a polymerization initiation assistant, a leveling agent, a wettability improver, a surfactant, a plasticizer, and an ultraviolet absorber. Agents, antioxidants, antistatic agents, inorganic fillers, organic fillers, pigments, dyes and the like.

The curable composition of the third aspect is cured when fired or irradiated with ultraviolet rays and / or electron beams. For example, a low refractive index film can be formed by applying the composition to a substrate, drying, and baking or irradiating with ultraviolet rays and / or electron beams. The drying conditions are usually 40 to 150 ° C. and 0.5 to 30 minutes. In the case of firing, the curing conditions are usually heated at 150 to 500 ° C. for 1 to 120 minutes. In the case of ultraviolet rays, the irradiation amount is usually 50 to 3000 mJ / cm ² under anaerobic conditions, and in the case of electron beams, the irradiation amount is 0.1 to 100 Mrad. it can.

  As the substrate, a substrate used for a known antireflection film or the like can be used, and examples thereof include those exemplified in the description of the first and second aspects of the present invention.

The antireflective film is a film in which a low refractive index film is formed on a substrate, but the low refractive index film containing the porous silica fine particles of the present invention has a low refractive index, and therefore can be suitably used as an antireflective film. . In the antireflection film, a low refractive index film, a high refractive index film, a medium refractive index film, a hard coat layer, an antistatic layer, and the like can be laminated on the substrate.
FIG. 1 shows an antireflection film 10 showing an embodiment of the present invention. As shown in FIG. 1, a hard coat layer 14 and a low refractive index layer 16 are laminated on a substrate 12.
Further, a high refractive index layer (not shown) may be further provided between the hard coat layer 14 and the low refractive index layer 16.
Further, an antistatic layer (not shown) may be further provided between the base material 12 and the hard coat layer 14, or directly on the antistatic layer without forming the hard coat layer 14. The low refractive index layer 16 may be formed.
In addition to the above layer structure, the antireflection film of the third aspect of the present invention has any known layer structure as long as it includes the low refractive index layer 16 containing the polycrystalline silica fine particles of the third aspect of the present invention. It may be.

The porous silica fine particles of the third aspect of the present invention are, for example, a temperature at which a liquid dispersion of silica fine particles obtained by the production method of the third aspect of the present invention is vacuum-dried, and more preferably organic substances can be removed, Usually, it can also be obtained as a powder by treating at a temperature of 40 ° C. or higher.
The porous silica fine particles according to the third aspect of the present invention include adsorbents, various column fillers, lubricants, paints, resins, rubber and paper fillers, modifiers, cosmetics in addition to the optical applications described above. Can be used for etc.
III. Fourth aspect The method for producing porous silica fine particles according to the fourth aspect of the present invention is at least one selected from water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols, and half ethers of diols. After hydrolyzing and condensing the silicon compound represented by the following formula (4) and the silicon compound represented by the following formula (5) and / or the silicon compound represented by the formula (6) in the presence of seeds In addition, an aprotic organic solvent and pure water or an aqueous acid solution are added, and porous silica particles are extracted into the aprotic organic solvent layer, and the average particle size of the obtained polycrystalline silica fine particles is 5 to 50 nm. It is.
SiX ₄ (4)
R ⁴ _p SiX _4-p (5)
R ⁵ _q SiX _4-q (6)
The definitions and specific examples of R ⁴ , X, p, R ⁵ , and q in the above formulas (4) to (6) are all as described in the description of the third aspect of the present invention. I will omit it.

  When the reaction liquid containing the porous silica fine particles after hydrolysis and condensation is applied as it is, acid amides and the like remain in the pores of the particles, leading to an increase in the refractive index of the coating film. In the fourth aspect of the present invention, the acid-amide etc. remaining in the particle pores can be removed by performing a liquid-liquid extraction treatment after hydrolysis condensation, so that the refractive index of the resulting coating film can be lowered.

  The silicon compounds represented by the formulas (4) to (6) can be mixed and hydrolyzed and condensed simultaneously. Further, the silicon compound represented by the formula (4) is hydrolyzed in the presence of at least one selected from water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols, and diol half ethers. After decomposing and condensing, the silicon compound represented by the formula (5) and / or the silicon compound represented by the formula (6) may be added for hydrolysis condensation. Thereafter, an aprotic organic solvent and pure water or an acid aqueous solution are added to extract porous silica particles into the aprotic organic solvent.

  In the production method according to the fourth aspect of the present invention, the total amount of silicon compounds represented by formulas (4) to (6) is 100 mol%, and the silicon compound of formula (4) is preferably 70 to 99 mols. %, More preferably 75 to 97 mol%.

  Specific examples of the basic compound, acid amide, diol, and half ether of diol used in the production method of the fourth aspect of the present invention are as described in the first and second aspects, and are omitted here. .

  The reaction temperature and reaction time for hydrolysis condensation and cocondensation can be appropriately determined in consideration of the type, amount, and the like of the alcohol, basic compound, acid amide, silicon compound and the like to be used. Usually, it hydrolyze-condenses at 20 to 100 degreeC for 1 to 24 hours.

The total concentration of the silicon compounds represented by the formulas (4) to (6) in the reaction solution is usually 0.5 to 10% by mass, preferably 1 to 8% by mass in terms of complete hydrolysis condensate. “Conversion to complete hydrolysis condensate” is as described in the third embodiment. By making the concentration of the silicon compound at the time of particle synthesis in the above range, coarsening of the particles can be prevented and fine particles having an average particle diameter of 5 to 50 nm can be obtained.
Here, the reaction solution does not include an aprotic organic solvent and pure water or an acid aqueous solution.

After the hydrolysis condensation, an aprotic organic solvent and pure water or an aqueous acid solution are added to extract silica particles into the aprotic organic solvent.
The aprotic solvent is preferably, for example, diethyl carbonate, ethylene carbonate, propylene carbonate, diethyl carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-acetate -Butyl, i-butyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methyl pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, acetic acid Methyl cyclohexyl, n-nonyl acetate, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl acetate Diethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate , Glycol diacetate, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, diethyl malonate, dimethyl phthalate, diethyl phthalate, etc. Ester solvents, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, Lenglycol dipropyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol di Butyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol dipropyl ether, dipropylene glycol dibutyl ether, ethyl ether, i-propyl ether, n-butyl ether, n-hexyl ether, 2 Ethylhexyl ether, ethylene oxide, 1,2-propylene oxide, dioxolane, 4-methyldioxolane, dioxane, dimethyldioxane, tetrahydrofuran, ether solvents such as 2-methyltetrahydrofuran, acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n -Butyl ketone, diethyl ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, methyl-n-hexyl ketone, di-i-butyl ketone, trimethylnonanone, cyclohexanone, 2-hexanone, methylcyclohexanone , 2,4-pentanedione, acetonylacetone, diacetone alcohol, acetophenone, fenchon and other ketone solvents, and n-pentane, i-pentane, n-hex Sun, i-hexane, n-heptane, i-heptane, 2,2,4-trimethylpentane, n-octane, i-octane, cyclohexane, methylcyclohexane, benzene, toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, Selected from hydrocarbon solvents such as n-propyl benzene, i-propyl benzene, diethylbenzene, i-butylbenzene, triethylbenzene, di-i-propyl benzene, n-amylnaphthalene, trimethylbenzene, etc. Two or more types may be used in combination.

  The acid in the acid aqueous solution is preferably a protonic acid, more preferably acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, oxalic acid, maleic acid, methylmalon. Acid, adipic acid, sebacic acid, gallic acid, butyric acid, meritic acid, arachidonic acid, shikimic acid, 2-ethylhexanoic acid, oleic acid, stearic acid, linoleic acid, linolenic acid, salicylic acid, benzoic acid, p-aminobenzoic acid , P-toluenesulfonic acid, benzenesulfonic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, formic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, tartaric acid, succinic acid, fumaric acid, itacone Acid, mesaconic acid, citraconic acid, malic acid, glutaric acid hydrolyzate, maleic anhydride Hydrolyzate is a hydrolyzate such as phthalic anhydride. The concentration of the acid aqueous solution is usually 0.01 to 5% by mass.

  When performing extraction operation, the ratio of reaction liquid / aprotic organic solvent / pure water or acid aqueous solution is usually 1 / 0.2 to 2 / 0.1 to 2 (mass ratio).

  After the extraction operation, the aprotic organic solvent layer is concentrated to obtain a sol-like silica particle solution. When the aprotic organic solvent layer is concentrated, a solvent having a boiling point higher than that of this solvent is preferably added.

According to the production method of the fourth aspect of the present invention, porous silica fine particles having an average particle diameter of 5 to 50 nm can be obtained. The average particle diameter is preferably 5 to 45 nm, and more preferably 5 to 40 nm. The average particle diameter is a number average particle diameter, and is measured by a transmission electron microscope observation image. The term “porous” as used in the present invention means that the specific surface area is 50 to 1000 m ² / g, preferably 50 to 800 m ² / g, more preferably 100 to 800 m ² / g. means. The specific surface area is measured by the BET method.
When the average particle size is within the above range, scattering of the obtained coating film in the visible light region can be suppressed. Further, due to being porous, the density is lowered, and the refractive index of the film containing such porous silica fine particles is lowered.

The curable composition of the fourth aspect of the present invention is obtained by dispersing the porous silica fine particles of the fourth aspect of the present invention in an organic solvent. As the organic solvent, the above aprotic organic solvents can be used, and alcohols having 1 to 8 carbon atoms, ketones having 3 to 10 carbon atoms, and ester based organic solvents having 3 to 10 carbon atoms can be used. . The porous silica fine particles are dispersed in an organic solvent at a concentration of preferably 0.5 to 30% by mass.
Such a composition is represented by the formula (4) in the presence of water, an alcohol having 1 to 3 carbon atoms, a basic compound, and at least one half ether compound selected from acid amides, diols and half ethers of diols. And hydrolyzing and condensing the silicon compound represented by formula (5) and / or formula (6), adding an organic solvent as necessary, and further removing unnecessary components such as distillation or liquid-liquid extraction as necessary It can manufacture by removing by a method.

  The curable composition containing the porous silica fine particles and the organic solvent of the fourth aspect of the present invention can be suitably used as a composition for forming a low refractive index film. In addition, the composition preferably includes a radical generator. Examples of the radical generator include a compound that thermally generates active radical species (thermal polymerization initiator) and a compound that generates active radical species by radiation (light) irradiation (radiation (light) polymerization initiator). Can be mentioned.

  Specific examples of the radiation (photo) polymerization initiator are the same as those described in the first and second aspects of the present invention, and are omitted here.

  The blending amount of the organic solvent and the radical generator in the fourth aspect of the present invention can be adjusted as appropriate, but the organic solvent is usually 500 to 10,000 parts by mass with respect to 100 parts by mass of the porous silica particles, and the radical generator is Usually, it is 1 to 10 parts by mass with respect to 100 parts by mass of the porous silica fine particles.

  The curable composition of the fourth aspect includes, as other components, a photosensitizer, a polymerization inhibitor, a polymerization initiation assistant, a leveling agent, a wettability improver, a surfactant, a plasticizer, an ultraviolet absorber, an oxidation agent. An inhibitor, an antistatic agent, an inorganic filler, an organic filler, a pigment, a dye, and the like can be included.

The curable composition of the fourth aspect is cured by firing or irradiation with ultraviolet rays and / or electron beams. For example, a low refractive index film can be formed by applying the composition to a substrate, drying, and baking or irradiating with ultraviolet rays and / or electron beams. The drying conditions are usually 40 to 150 ° C. and 0.5 to 30 minutes. In the case of firing, the curing conditions are usually heated at 150 to 500 ° C. for 1 to 120 minutes. In the case of ultraviolet rays, it is usually 50 to 3000 mJ / cm ² under anaerobic conditions, and in the case of an electron beam, it is 0.1 to 100 Mrad.

  As the substrate, a substrate used for a known antireflection film or the like can be used. Specific examples of the substrate material are the same as those described in the first and second aspects, and are omitted here.

The antireflective film is a film in which a low refractive index film is formed on the substrate, but the low refractive index film containing the porous silica fine particles according to the fourth aspect of the present invention has a low refractive index. Can be suitably used. In the antireflection film, a low refractive index film, a high refractive index film, a medium refractive index film, a hard coat layer, an antistatic layer, and the like can be laminated on the substrate.
FIG. 1 shows an antireflection film 10 showing an embodiment of the present invention. As shown in FIG. 1, a hard coat layer 14 and a low refractive index layer 16 are laminated on a substrate 12.
Further, a high refractive index layer (not shown) may be further provided between the hard coat layer 14 and the low refractive index layer 16.
Further, an antistatic layer (not shown) may be further provided between the base material 12 and the hard coat layer 14, or directly on the antistatic layer without forming the hard coat layer 14. The low refractive index layer 16 may be formed.
In addition to the above layer structure, the antireflection film of the fourth aspect of the present invention has any known layer structure as long as it includes the low refractive index layer 16 containing the polycrystalline silica fine particles of the fourth aspect of the present invention. It may be.

The porous silica fine particles of the fourth aspect of the present invention are, for example, a temperature at which a liquid dispersion of silica particles obtained by the production method of the fourth aspect of the present invention is vacuum-dried, and more preferably organic substances can be removed, Usually, it can also obtain as a powder by processing at the temperature of 40 degreeC or more.
The porous silica fine particles according to the fourth aspect of the present invention include adsorbents, various column fillers, lubricants, paints, resins, rubber and paper fillers, modifiers, cosmetics in addition to the optical applications described above. Can be used for etc.

[Example]
EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated further in detail, the scope of the present invention is not limited to description of these Examples. In the examples, unless otherwise specified, the amount of each component means “parts” by mass and “%” means mass%.

[Polymeric silica fine particles of the first aspect]
Example 1-1
In a quartz separable flask, add 64.85 g of tetraethoxysilane (manufactured by Dow Corning Silicone Co., Ltd., AY43-101), 692.72 g of ethanol, 40.00 g of N, N-dimethylacetamide, and uniformly After mixing, 200.00 g of a 25% aqueous solution of ammonia was added. Thereafter, the solution was reacted at 50 ° C. for 6 hours while stirring, and 2.43 g of vinyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ6300) was added and reacted at 50 ° C. for 2 hours. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain a porous silica particle solution 1-1.
After adding 10 g of ethanol to 1 g of the obtained solution 1-1 and mixing, one drop was dropped on a carbon grid for a transmission electron microscope, and then dried at room temperature for 24 hours, and field emission electron microscope JEM manufactured by JEOL Ltd. Observation was performed using −2010F, and the average particle diameter of the porous silica particles was measured.
10 g of the obtained solution 1-1 was placed in an aluminum dish and dried on a hot plate at 150 ° C. for 1 hour to obtain a powder sample of porous silica particles 1. The BET specific surface area of the obtained porous silica particle powder was measured using AUTOSORB-1 manufactured by Quantachrome Instruments.
The measurement results are shown in Table 1.

Example 1-2
In a quartz separable flask, 48.58 g of tetramethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-04), 20.28 g of vinyltrimethoxysilane, 328.14 g of ethanol, and 300.00 g of ethylene glycol were uniformly added. After mixing, 303.00 g of a 1% aqueous solution of tetramethylammonium hydroxide was added. Thereafter, the solution was reacted at 60 ° C. for 4 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of ethyl acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added and stirred and allowed to stand. The upper layer separated into two layers was separated, 500.00 g of propylene glycol monoethyl ether was added, and then concentrated to a solid content concentration of 5% by a rotary evaporator to obtain a porous silica particle solution 1-2.
The average particle diameter and specific surface area were measured in the same manner as in Example 1-1. The measurement results are shown in Table 1.

Example 1-3
In a quartz separable flask, 29.99 g of tetraethoxysilane, 838.05 g of methanol, and 30.00 g of propylene glycol were added and mixed uniformly, and then 101.00 g of a 1% aqueous solution of ammonia was added. Then, the solution was reacted at 40 ° C. for 8 hours with stirring, and 1.11 g of vinyltrimethoxysilane and 1.85 g of methacryloxypropyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ-6030) were added. The mixture was added and reacted at 40 ° C. for 2 hours. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain porous silica particle solution 1-3.
The average particle diameter and specific surface area were measured in the same manner as in Example 1-1. The measurement results are shown in Table 1.

Example 1-4
In a quartz separable flask, 106.24 g of tetraethoxysilane, 420.49 g of methanol, and 200.00 g of 1,2-butanediol were added and mixed uniformly, and then 100.00 g of a 10% aqueous solution of ammonia and ultrapure water. 160.00 g was added. Then, the solution was allowed to react at 30 ° C. for 12 hours while stirring, and further 13.28 g of acryloxypropyltrimethoxysilane (AY43-310M, manufactured by Toray Dow Corning Silicone Co., Ltd.) was added and reacted at 60 ° C. for 1 hour. I let you. After cooling the reaction solution to room temperature, 1000.00 g of propylene glycol methyl ether acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated and concentrated with a rotary evaporator until the solid content concentration became 5% to obtain a porous silica particle solution 1-4.
The average particle diameter and specific surface area were measured in the same manner as in Example 1-1. The measurement results are shown in Table 1.

Comparative Example 1-1
In a quartz separable flask, 69.35 g of tetraethoxysilane, 690.65 g of ethanol, and 40.00 g of N, N-dimethylacetamide were added and mixed uniformly, and then 200.00 g of a 25% aqueous solution of ammonia was added. Thereafter, the solution was reacted at 50 ° C. for 8 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone was added and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain porous silica particle solution 1-5.
The average particle diameter and specific surface area were measured in the same manner as in Example 1-1. The measurement results are shown in Table 1.

Comparative Example 1-2
In a quartz separable flask, add 48.58 g of tetramethoxysilane, 20.28 g of vinyltrimethoxysilane, and 628.14 g of ethanol, and after mixing uniformly, add 303.00 g of 1% aqueous solution of tetramethylammonium hydroxide. did. Thereafter, the solution was reacted at 60 ° C. for 4 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of ethyl acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added and stirred and allowed to stand. The upper layer separated into two layers was separated, and 500.00 g of propylene glycol monoethyl ether was added, followed by concentration to a solid content concentration of 5% with a rotary evaporator to obtain silica particle solution 1-6.
The average particle diameter and specific surface area were measured in the same manner as in Example 1-1. The measurement results are shown in Table 1.

[Evaluation of film made of composition containing porous silica fine particles of first aspect]
Evaluation Example 1-1
To 100 g of the solution 1-1 obtained in Example 1-1, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one (Ciba Specialty) was used as a photopolymerization initiator. 0.25 g of Chemicals Co., Ltd., Irgacure 907) was added and mixed until uniform, and then applied to a 4-inch silicon wafer to a film thickness of 100 nm by a spin coat method. After drying on a hot plate for 3 minutes, ultraviolet rays were irradiated under a light irradiation condition of 1 J / cm ² with a high-pressure mercury lamp under nitrogen to obtain a coating film of porous silica particles 1-1.
The refractive index of the obtained coating film was measured using an n & k analyzer 1500 manufactured by n & k Technology. Moreover, ethanol was dripped on the obtained coating film, and it was left to stand at room temperature for 1 hour, and then ethanol was wiped off.
○: No change in appearance of coating film (good curability)
×: Change in appearance of coating film is observed (hardness failure)
The evaluation results are shown in Table 1.

Evaluation Example 1-2
A coating film was obtained in the same manner as in Evaluation Example 1-1 except that the solution 1-2 obtained in Example 1-2 was used instead of the solution 1-1.
The obtained coating film was evaluated in the same manner as in Evaluation Example 1-1. The evaluation results are shown in Table 1.

Evaluation Example 1-3
The solution 1-3 obtained in Example 1-3 was used instead of the solution 1-1, and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane-1 was used as a photopolymerization initiator. A coating film was obtained in the same manner as in Evaluation Example 1-1 except that 1-hydroxycyclohexyl phenyl ketone (manufactured by Ciba Specialty Chemicals Co., Ltd., Irgacure 184) was used instead of -one.
The obtained coating film was evaluated in the same manner as in Evaluation Example 1-1. The evaluation results are shown in Table 1.

Evaluation Example 1-4
A coating film was obtained in the same manner as in Evaluation Example 1-3 except that the solution 1-4 obtained in Example 1-4 was used instead of the solution 1-3.
The obtained coating film was evaluated in the same manner as in Evaluation Example 1-1. The evaluation results are shown in Table 1.

Evaluation Examples 1-5 and 1-6
A coating film was obtained in the same manner as in Evaluation Example 1 except that the solutions 1-5 and 1-6 obtained in Comparative Examples 1-1 and 1-2 were used in place of the solution 1-1.
The obtained coating film was evaluated in the same manner as in Evaluation Example 1-1. The evaluation results are shown in Table 1.

[Polymeric silica fine particles of the second aspect]
Example 2-1
In a quartz separable flask, add 50.96 g of tetraethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., AY43-101), 700.98 g of ethanol, 40.00 g of N, N-dimethylacetamide, and uniformly After mixing, 200.00 g of a 25% aqueous solution of ammonia was added. Thereafter, the solution was reacted at 50 ° C. for 6 hours while stirring, and further 2.11 g of vinyltrimethoxysilane (Toray Dow Corning Silicone Co., Ltd., SZ6300) and 3,3,3-trifluoropropyltrimethoxysilane. 5.95 g (manufactured by Shin-Etsu Chemical Co., Ltd., KBM7103) was added and reacted at 50 ° C. for 2 hours. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain a porous silica particle solution 2-1.
10 g of ethanol was added to 1 g of the solution 2-1 obtained in Example 2-1, mixed, and then dropped on a carbon grid for a transmission electron microscope, and then dried at room temperature for 24 hours. Observation was performed using a field emission electron microscope JEM-2010F, and the particle size of the porous silica particles was measured.
10 g of the solution 2-1 obtained in Example 2-1 was placed in an aluminum dish and dried on a hot plate at 150 ° C. for 1 hour to obtain a powder sample of porous silica particles 2-1. The BET specific surface area of the obtained porous silica particle powder was measured using AUTOSORB-1 manufactured by Quantachrome Instruments.
The measurement results are shown in Table 2.

Example 2-2
In a quartz separable flask, 44.89 g of tetramethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-04), 19.01 g of vinyltrimethoxysilane, 2-perfluorooctylethyltriethoxysilane (Toray Dow Corning) -Silicone Co., Ltd. product, AY43-158E) 2.61g, ethanol 330.49g, and ethylene glycol 300.00g were added and mixed uniformly, and then 303.00g of 1% aqueous solution of tetramethylammonium hydroxide was added. Thereafter, the solution was reacted at 60 ° C. for 4 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of ethyl acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added and stirred and allowed to stand. The upper layer separated into two layers was separated, and 500.00 g of propylene glycol monoethyl ether was added, followed by concentration to a solid content concentration of 5% with a rotary evaporator to obtain a porous silica particle solution 2-2.
The average particle diameter and specific surface area were measured in the same manner as in Example 2-1. The measurement results are shown in Table 2.

Example 2-3
In a quartz separable flask, 22.24 g of tetraethoxysilane, 841.97 g of methanol and 30.00 g of propylene glycol were added and mixed uniformly, and then 101.00 g of a 1% aqueous solution of ammonia was added. Then, the solution was reacted at 40 ° C. for 8 hours while stirring, and 0.92 g of vinyltrimethoxysilane and 1.54 g of methacryloxypropyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ-6030) were added. The mixture was added and reacted at 40 ° C. for 1 hour. Subsequently, 2.33 g of 2-perfluorohexylethyltrimethoxysilane (GE Toshiba Silicone Co., Ltd., TSL8257) was added and reacted at 40 ° C. for 1 hour. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated and concentrated with a rotary evaporator until the solid content concentration became 5% to obtain a porous silica particle solution 2-3.
The average particle diameter and specific surface area were measured in the same manner as in Example 2-1. The measurement results are shown in Table 2.

Example 2-4
In a quartz separable flask, 94.54 g of tetraethoxysilane, 427.38 g of methanol, and 200.00 g of 1,2-butanediol were added and mixed uniformly, and then 100.00 g of a 10% aqueous solution of ammonia and ultrapure water. 160.00 g was added. Thereafter, the solution was reacted at 30 ° C. for 12 hours while stirring, and further 12.22 g of acryloxypropyltrimethoxysilane (AY43-310M, manufactured by Toray Dow Corning Silicone Co., Ltd.) and 3,3-di (trifluoro). 5.86 g of methyl) -3-fluoropropyltriethoxysilane (Toray Dow Corning Silicone Co., Ltd., Z-2858) was added and reacted at 60 ° C. for 1 hour. After cooling the reaction solution to room temperature, 1000.00 g of propylene glycol methyl ether acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain a porous silica particle solution 2-4.
The average particle diameter and specific surface area were measured in the same manner as in Example 2-1. The measurement results are shown in Table 2.

Comparative Example 2-1
In a quartz separable flask, 69.35 g of tetraethoxysilane, 690.65 g of ethanol, and 40.00 g of N, N-dimethylacetamide were added and mixed uniformly, and then 200.00 g of a 25% aqueous solution of ammonia was added. Thereafter, the solution was reacted at 50 ° C. for 8 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone was added and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain porous silica particle solution 2-5.
The average particle diameter and specific surface area were measured in the same manner as in Example 2-1. The measurement results are shown in Table 2.

Comparative Example 2-2
In a quartz separable flask, add 44.89 g of tetramethoxysilane, 19.01 g of vinyltrimethoxysilane, and 630.49 g of ethanol, and after mixing uniformly, add 303.00 g of 1% aqueous solution of tetramethylammonium hydroxide. did. Thereafter, the solution was reacted at 60 ° C. for 4 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of ethyl acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added and stirred and allowed to stand. The upper layer separated into two layers was separated, and 500.00 g of propylene glycol monoethyl ether was added, followed by concentration to a solid content concentration of 5% with a rotary evaporator to obtain a silica particle solution 2-6.
The average particle diameter and specific surface area were measured in the same manner as in Example 2-1. The measurement results are shown in Table 2.

Comparative Example 2-3
In a quartz separable flask, 106.24 g of tetraethoxysilane, 420.49 g of methanol, and 200.00 g of 1,2-butanediol were added and mixed uniformly, and then 100.00 g of a 10% aqueous solution of ammonia and ultrapure water. 160.00 g was added. Thereafter, the solution was reacted at 30 ° C. for 12 hours while stirring, and 13.28 g of acryloxypropyltrimethoxysilane was further added and reacted at 60 ° C. for 1 hour. After cooling the reaction solution to room temperature, 1000.00 g of propylene glycol methyl ether acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain porous silica particle solution 2-7.
The average particle diameter and specific surface area were measured in the same manner as in Example 2-1. The measurement results are shown in Table 2.

[Evaluation of film made of composition containing porous silica fine particles of second aspect]
Evaluation Example 2-1
To 100 g of the solution 2-1 obtained in Example 2-1, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one (Ciba Specialty) was used as a photopolymerization initiator. 0.25 g of Chemicals Co., Ltd., Irgacure 907) was added and mixed until uniform, and then applied to a 4-inch silicon wafer to a film thickness of 100 nm by a spin coat method. After drying on a hot plate for 3 minutes, ultraviolet rays were irradiated under a light irradiation condition of 1 J / cm ² with a high-pressure mercury lamp under nitrogen to obtain a coating film of porous silica particles 2-1.
The refractive index of the obtained coating film was measured using an n & k analyzer 1500 manufactured by n & k Technology. Moreover, ethanol was dripped on the obtained coating film, and it was left to stand at room temperature for 1 hour, and then ethanol was wiped off.
○: No change in appearance of coating film (good curability)
×: Change in appearance of coating film is observed (hardness failure)
After attaching a fingerprint on the obtained coating film, the surface of the coating film was wiped off with a non-woven fabric (Asahi Kasei Fibers Co., Ltd., Bencott S-2), and the appearance of the coating film was visually observed. Evaluated.
○: Fingerprint traces on the surface of the coating film were completely wiped off. Δ: Fingerprint traces on the surface of the coating film remained slightly. X: Almost fingerprint traces on the surface of the coating film remained. Table 2 shows the evaluation results.

Evaluation Example 2-2
A coating film was obtained in the same manner as in Evaluation Example 2-1, except that the solution 2-2 obtained in Example 2-2 was used instead of the solution 2-1.
The obtained coating film was evaluated in the same manner as in Evaluation Example 2-1. The evaluation results are shown in Table 2.

Evaluation Example 2-3
The solution 2-3 obtained in Example 2-3 was used instead of the solution 2-1, and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane-1 was used as a photopolymerization initiator. A coating film was obtained in the same manner as in Evaluation Example 2-1, except that 1-hydroxycyclohexyl phenyl ketone (manufactured by Ciba Specialty Chemicals Co., Ltd., Irgacure 184) was used instead of -one.
The obtained coating film was evaluated in the same manner as in Evaluation Example 2-1. The evaluation results are shown in Table 2.

Evaluation Example 2-4
A coating film was obtained in the same manner as in Evaluation Example 2-3 except that the solution 2-4 obtained in Example 2-4 was used instead of the solution 2-3.
The obtained coating film was evaluated in the same manner as in Evaluation Example 2-1. The evaluation results are shown in Table 2.

Evaluation Examples 2-5 and 2-6
A coating film was obtained in the same manner as in Evaluation Example 2-1, except that the solutions 2-5 and 2-6 obtained in Comparative Examples 2-1 and 2-2 were used in place of the solution 2-1.
The obtained coating film was evaluated in the same manner as in Evaluation Example 2-1. The evaluation results are shown in Table 2.

Evaluation Example 2-7
A coating film was obtained in the same manner as in Evaluation Example 2-3 except that the solution 2-7 obtained in Comparative Example 2-3 was used in place of the solution 2-3.
The obtained coating film was evaluated in the same manner as in Evaluation Example 2-1. The evaluation results are shown in Table 2.

表２から本実施例の多孔質シリカ微粒子を用いた低屈折率膜は、屈折率が低くかつ耐汚染性に優れることが分かる。

It can be seen from Table 2 that the low refractive index film using the porous silica fine particles of this example has a low refractive index and excellent stain resistance.

[Polymeric silica fine particles of the third aspect]
Example 3-1
In a quartz separable flask, add 64.85 g of tetraethoxysilane (manufactured by Dow Corning Silicone Co., Ltd., AY43-101), 692.72 g of ethanol, 40.00 g of N, N-dimethylacetamide, and uniformly After mixing, 200.00 g of a 25% aqueous solution of ammonia was added. Thereafter, the solution was reacted at 50 ° C. for 6 hours while stirring, and 2.43 g of vinyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ6300) was added and reacted at 50 ° C. for 2 hours. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain a porous silica particle solution 3-1.
After adding and mixing 10 g of ethanol to 1 g of the solution 3-1 obtained in Example 3-1, one drop was dropped on a carbon grid for a transmission electron microscope and then dried at room temperature for 24 hours. Observation was performed using a field emission electron microscope JEM-2010F, and the particle size of the porous silica particles was measured.
10 g of the solution 1 obtained in Example 3-1 was placed in an aluminum dish and dried on a hot plate at 150 ° C. for 1 hour to obtain a powder sample of porous silica particles 3-1. The BET specific surface area of the obtained porous silica particle powder was measured using AUTOSORB-1 manufactured by Quantachrome Instruments.
Table 3 shows the measurement results.

Example 3-2
In a separable flask made of quartz, 51.40 g of tetramethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-04), 325.89 g of ethanol, and 300.00 g of ethylene glycol are added and mixed uniformly, and then tetramethylammonium. 303.00 g of a 1% aqueous solution of hydroxide was added. Thereafter, the solution was reacted at 60 ° C. for 4 hours while stirring, and 19.71 g of methyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ6070) was added and reacted at 60 ° C. for 1 hour. After cooling the reaction solution to room temperature, 1000.00 g of ethyl acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, 500.00 g of propylene glycol monoethyl ether was added, and then concentrated to a solid content concentration of 5% by a rotary evaporator to obtain a porous silica particle solution 3-2.
The average particle diameter and specific surface area were measured in the same manner as in Example 3-1. Table 3 shows the measurement results.

Example 3-3
In a quartz separable flask, 29.99 g of tetraethoxysilane, 838.05 g of methanol, and 30.00 g of propylene glycol were added and mixed uniformly, and then 101.00 g of a 1% aqueous solution of ammonia was added. Then, the solution was reacted at 40 ° C. for 8 hours with stirring, and 1.11 g of vinyltrimethoxysilane and 1.85 g of methacryloxypropyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ-6030) were added. The mixture was added and reacted at 40 ° C. for 2 hours. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated and concentrated with a rotary evaporator until the solid content concentration became 5% to obtain a porous silica particle solution 3-3.
The average particle diameter and specific surface area were measured in the same manner as in Example 3-1. Table 3 shows the measurement results.

Example 3-4
In a quartz separable flask, 94.54 g of tetraethoxysilane, 427.38 g of methanol, and 200.00 g of 1,2-butanediol were added and mixed uniformly, and then 100.00 g of a 10% aqueous solution of ammonia and ultrapure water. 160.00 g was added. Thereafter, the solution was reacted at 30 ° C. for 12 hours while stirring, and further 12.22 g of acryloxypropyltrimethoxysilane (AY43-310M, manufactured by Toray Dow Corning Silicone Co., Ltd.) and 3,3-di (trifluoro). 5.86 g of methyl) -3-fluoropropyltriethoxysilane (Toray Dow Corning Silicone Co., Ltd., Z-2858) was added and reacted at 60 ° C. for 1 hour. After cooling the reaction solution to room temperature, 1000.00 g of propylene glycol methyl ether acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated and concentrated with a rotary evaporator until the solid content concentration became 5% to obtain a porous silica particle solution 3-4.
The average particle diameter and specific surface area were measured in the same manner as in Example 3-1. Table 3 shows the measurement results.

Comparative Example 3-1
In a quartz separable flask, 69.35 g of tetraethoxysilane, 690.65 g of ethanol, and 40.00 g of N, N-dimethylacetamide were added and mixed uniformly, and then 200.00 g of a 25% aqueous solution of ammonia was added. Thereafter, the solution was reacted at 50 ° C. for 8 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone was added and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain porous silica particle solution 3-5.
The average particle diameter and specific surface area were measured in the same manner as in Example 3-1. Table 3 shows the measurement results.

Comparative Example 3-2
In a separable flask made of quartz, 64.85 g of tetraethoxysilane, 2.43 g of vinyltrimethoxysilane, 692.72 g of ethanol, 40.00 g of N, N-dimethylacetamide were added and mixed uniformly, and then 25% of ammonia. 200.00 g of aqueous solution was added. Thereafter, the solution was reacted at 50 ° C. for 8 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain porous silica particle solution 3-6.
The average particle diameter and specific surface area were measured in the same manner as in Example 3-1. Table 3 shows the measurement results.

Comparative Example 3-3
In a quartz separable flask, 48.58 g of tetramethoxysilane and 628.14 g of ethanol were added and mixed uniformly, and then 303.00 g of a 1% aqueous solution of tetramethylammonium hydroxide was added. Thereafter, the solution was reacted at 60 ° C. for 4 hours with stirring, and 20.28 g of vinyltrimethoxysilane was further added and reacted at 60 ° C. for 1 hour. After cooling the reaction solution to room temperature, 1000.00 g of ethyl acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and 500.00 g of propylene glycol monoethyl ether was added, followed by concentration to a solid content concentration of 5% with a rotary evaporator to obtain silica particle solution 3-7.
The average particle diameter and specific surface area were measured in the same manner as in Example 3-1. Table 3 shows the measurement results.

[Evaluation of film made of composition containing porous silica fine particles of third aspect]
Evaluation Example 3-1
To 100 g of the solution 3-1 obtained in Example 3-1, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one (Ciba Specialty) was used as a photopolymerization initiator. 0.25 g of Chemicals Co., Ltd., Irgacure 907) was added and mixed until uniform, then applied to a 4-inch silicon wafer by spin coating to a film thickness of 100 nm, and then at 80 ° C. After drying on a hot plate for 3 minutes, ultraviolet rays were irradiated under a light irradiation condition of 1 J / cm ² with a high-pressure mercury lamp under nitrogen to obtain a coating film of porous silica particles 3-1.
The refractive index of the obtained coating film was measured using an n & k analyzer 1500 manufactured by n & k Technology. Moreover, ethanol was dripped on the obtained coating film, and it was left to stand at room temperature for 1 hour, and then ethanol was wiped off.
○: No change in appearance of coating film (good curability)
×: Change in appearance of coating film is observed (hardness failure)
Pure water was dropped onto the obtained coating film, left at room temperature for 24 hours, wiped off the pure water, the appearance of the coating film was visually observed, and water resistance was evaluated according to the following criteria.
○: No change is observed in the appearance of the coating film ×: Changes in the appearance of the coating film are observed Table 3 shows the evaluation results.

Evaluation Example 3-2
The solution 3-2 obtained in Example 3-2 was applied on a 4-inch silicon wafer by spin coating so as to have a film thickness of 100 nm, then on an 80 ° C. hot plate in the atmosphere for 2 minutes, and then in the atmosphere. The film was dried on a hot plate at 200 ° C. for 3 minutes and then baked in a furnace at 420 ° C. for 60 minutes under nitrogen to obtain a coating film of porous silica particles 3-2.
The obtained coating film was evaluated in the same manner as in Evaluation Example 3-1. The evaluation results are shown in Table 3.

Evaluation Example 3-3
The solution 3-3 obtained in Example 3-3 was used in place of the solution 3-1, and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane-1 was used as a photopolymerization initiator. A coating film was obtained in the same manner as in Evaluation Example 3-1, except that 1-hydroxycyclohexyl phenyl ketone (manufactured by Ciba Specialty Chemicals Co., Ltd., Irgacure 184) was used instead of -one.
The obtained coating film was evaluated in the same manner as in Evaluation Example 3-1. The evaluation results are shown in Table 3.

Evaluation Example 3-4
A coating film was obtained in the same manner as in Evaluation Example 3-3 except that the solution 3-4 obtained in Example 3-4 was used instead of the solution 3-3.
The obtained coating film was evaluated in the same manner as in Evaluation Example 3-1. The evaluation results are shown in Table 3.

Evaluation Example 3-5
A coating film was obtained in the same manner as in Evaluation Example 3-2 except that the solution 3-5 obtained in Comparative Example 3-1 was used instead of the solution 3-2.
The obtained coating film was evaluated in the same manner as in Evaluation Example 3-1. The evaluation results are shown in Table 3.

Evaluation Example 3-6
A coating film was obtained in the same manner as in Evaluation Example 3-1, except that the solution 3-6 obtained in Comparative Example 3-2 was used instead of the solution 3-1.
The obtained coating film was evaluated in the same manner as in Evaluation Example 3-1. The evaluation results are shown in Table 3.

Evaluation Example 3-7
A coating film was obtained in the same manner as in Evaluation Example 3-3 except that the solution 3-7 obtained in Comparative Example 3-3 was used instead of the solution 3-3.
The obtained coating film was evaluated in the same manner as in Evaluation Example 3-1. The evaluation results are shown in Table 3.

[Porous Silica Fine Particles of Fourth Embodiment]
Example 4-1
In a quartz separable flask, add 64.85 g of tetraethoxysilane (manufactured by Dow Corning Silicone Co., Ltd., AY43-101), 692.72 g of ethanol, 40.00 g of N, N-dimethylacetamide, and uniformly After mixing, 200.00 g of a 25% aqueous solution of ammonia was added. Thereafter, the solution was reacted at 50 ° C. for 6 hours while stirring, and 2.43 g of vinyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ6300) was added and reacted at 50 ° C. for 2 hours. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and concentrated to a solid content concentration of 5% with a rotary evaporator to obtain a porous silica particle solution 4-1.
After adding and mixing 10 g of ethanol to 1 g of the solution 4-1 obtained in Example 4-1, one drop was dropped on a carbon grid for a transmission electron microscope and then dried at room temperature for 24 hours. Observation was performed using a field emission electron microscope JEM-2010F, and the particle size of the porous silica particles was measured.
10 g of the solution 4-1 obtained in Example 4-1 was placed in an aluminum dish and dried on a hot plate at 150 ° C. for 1 hour to obtain a powder sample of porous silica particles 4-1. The BET specific surface area of the obtained porous silica particle powder was measured using AUTOSORB-1 manufactured by Quantachrome Instruments.
Table 4 shows the measurement results.

Example 4-2
In a quartz separable flask, 48.58 g of tetramethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-04), 20.28 g of vinyltrimethoxysilane, 328.14 g of ethanol, and 300.00 g of ethylene glycol were uniformly added. After mixing, 303.00 g of a 1% aqueous solution of tetramethylammonium hydroxide was added. Thereafter, the solution was reacted at 60 ° C. for 4 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of ethyl acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and 500.00 g of propylene glycol monoethyl ether was added, followed by concentration to a solid content concentration of 5% with a rotary evaporator to obtain a porous silica particle solution 4-2.
The average particle diameter and specific surface area were measured in the same manner as in Example 4-1. Table 4 shows the measurement results.

Example 4-3
In a quartz separable flask, 29.99 g of tetraethoxysilane, 838.05 g of methanol, and 30.00 g of propylene glycol were added and mixed uniformly, and then 101.00 g of a 1% aqueous solution of ammonia was added. Then, the solution was reacted at 40 ° C. for 8 hours with stirring, and 1.11 g of vinyltrimethoxysilane and 1.85 g of methacryloxypropyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ-6030) were added. The mixture was added and reacted at 40 ° C. for 2 hours. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated and concentrated with a rotary evaporator until the solid content concentration became 5%, to obtain a porous silica particle solution 4-3.
The average particle diameter and specific surface area were measured in the same manner as in Example 4-1. Table 4 shows the measurement results.

Example 4-4
In a quartz separable flask, 94.54 g of tetraethoxysilane, 427.38 g of methanol, and 200.00 g of 1,2-butanediol were added and mixed uniformly, and then 100.00 g of a 10% aqueous solution of ammonia and ultrapure water. 160.00 g was added. Thereafter, the solution was reacted at 30 ° C. for 12 hours while stirring, and further 12.22 g of acryloxypropyltrimethoxysilane (AY43-310M, manufactured by Toray Dow Corning Silicone Co., Ltd.) and 3,3-di (trifluoro). 5.86 g of methyl) -3-fluoropropyltriethoxysilane (Toray Dow Corning Silicone Co., Ltd., Z-2858) was added and reacted at 60 ° C. for 1 hour. After cooling the reaction solution to room temperature, 1000.00 g of propylene glycol methyl ether acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated and concentrated with a rotary evaporator until the solid content concentration became 5% to obtain a porous silica particle solution 4-4.
The average particle diameter and specific surface area were measured in the same manner as in Example 4-1. Table 4 shows the measurement results.

Comparative Example 4-1
In a quartz separable flask, 69.35 g of tetraethoxysilane, 690.65 g of ethanol, and 40.00 g of N, N-dimethylacetamide were added and mixed uniformly, and then 200.00 g of a 25% aqueous solution of ammonia was added. Thereafter, the solution was reacted at 50 ° C. for 8 hours while stirring. After cooling the reaction solution to room temperature, 1000.00 g of methyl isobutyl ketone was added, and the mixture was concentrated with a rotary evaporator until the solid content concentration became 5% to obtain porous silica particle solution 4-5.
The average particle diameter and specific surface area were measured in the same manner as in Example 4-1. Table 4 shows the measurement results.

Comparative Example 4-2
In a separable flask made of quartz, 48.58 g of tetramethoxysilane, 20.28 g of vinyltrimethoxysilane, 328.14 g of ethanol, and 300.00 g of ethylene glycol were added and mixed uniformly, and then 1% of tetramethylammonium hydroxide. 303.00 g of aqueous solution was added. Thereafter, the solution was reacted at 60 ° C. for 4 hours while stirring. After cooling the reaction solution to room temperature, 500.00 g of propylene glycol monoethyl ether was added and then concentrated to a solid content concentration of 5% by a rotary evaporator to obtain porous silica particle solution 4-6.
The average particle diameter and specific surface area were measured in the same manner as in Example 4-1. Table 4 shows the measurement results.

Comparative Example 4-3
In a quartz separable flask, 48.58 g of tetramethoxysilane and 628.14 g of ethanol were added and mixed uniformly, and then 303.00 g of a 1% aqueous solution of tetramethylammonium hydroxide was added. Thereafter, the solution was reacted at 60 ° C. for 4 hours with stirring, and 20.28 g of vinyltrimethoxysilane was further added and reacted at 60 ° C. for 1 hour. After cooling the reaction solution to room temperature, 1000.00 g of ethyl acetate and 1000.00 g of a 0.1% aqueous solution of oxalic acid were added, and the mixture was stirred and allowed to stand. The upper layer separated into two layers was separated, and 500.00 g of propylene glycol monoethyl ether was added, followed by concentration to a solid content concentration of 5% with a rotary evaporator to obtain a silica particle solution 4-7.
The average particle diameter and specific surface area were measured in the same manner as in Example 4-1. Table 4 shows the measurement results.

[Evaluation of Film Containing Composition Containing Porous Silica Fine Particles of Fourth Embodiment]
Evaluation Example 4-1
To 100 g of the solution 4-1 obtained in Example 4-1, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one (Ciba Specialty) was used as a photopolymerization initiator. 0.25 g of Chemicals Co., Ltd., Irgacure 907) was added and mixed until uniform, then applied to a 4-inch silicon wafer by spin coating to a film thickness of 100 nm, and then at 80 ° C. After drying on a hot plate for 3 minutes, ultraviolet rays were irradiated under a light irradiation condition of 1 J / cm ² with a high-pressure mercury lamp under nitrogen to obtain a coating film of porous silica particles 4-1.
The refractive index of the obtained coating film was measured using an n & k analyzer 1500 manufactured by n & k Technology. Moreover, ethanol was dripped on the obtained coating film, and it was left to stand at room temperature for 1 hour, and then ethanol was wiped off.
○: No change in appearance of coating film (good curability)
×: Change in appearance of coating film is observed (hardness failure)
The evaluation results are shown in Table 4.

Evaluation Example 4-2
A coating film was obtained in the same manner as in Evaluation Example 4-1, except that the solution 2 obtained in Example 4-2 was used instead of the solution 4-1.
The obtained coating film was evaluated in the same manner as in Evaluation Example 4-1. The evaluation results are shown in Table 4.

Evaluation Example 4-3
The solution 4-3 obtained in Example 4-3 was used instead of the solution 4-1, and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1 was used as a photopolymerization initiator. A coating film was obtained in the same manner as in Evaluation Example 4-1, except that 1-hydroxycyclohexyl phenyl ketone (Irgacure 184 manufactured by Ciba Specialty Chemicals Co., Ltd.) was used instead of -one.
The obtained coating film was evaluated in the same manner as in Evaluation Example 4-1. The evaluation results are shown in Table 4.

Evaluation Example 4-4
A coating film was obtained in the same manner as in Evaluation Example 4-3 except that the solution 4-4 obtained in Example 4-4 was used instead of the solution 4-3.
The obtained coating film was evaluated in the same manner as in Evaluation Example 4-1. The evaluation results are shown in Table 4.

Evaluation Examples 4-5 and 4-6
A coating film was obtained in the same manner as in Evaluation Example 4-1, except that the solutions 4-5 and 4-6 obtained in Comparative Examples 4-1 and 4-2 were used in place of the solution 4-1.
The obtained coating film was evaluated in the same manner as in Evaluation Example 4-1. The evaluation results are shown in Table 4.

Evaluation Example 4-7
A coating film was obtained in the same manner as in Evaluation Example 4-3 except that the solution 4-7 obtained in Comparative Example 4-3 was used instead of the solution 4-3.
The obtained coating film was evaluated in the same manner as in Evaluation Example 4-1. The evaluation results are shown in Table 4.

  The porous silica fine particles of the present invention can be used as a material for a low refractive index film. In addition, the low refractive index film obtained by curing the curable composition containing the porous silica fine particles of the present invention provides a particularly good antireflection effect, so that it can be used as a low refractive index forming material for the antireflection film. Can be used.

Claims (22)

Porous silica fine particles comprising a silicon compound represented by the following formula (1) and a hydrolyzate and / or hydrolysis condensate of the silicon compound represented by the following formula (2) and having an average particle diameter of 5 to 50 nm .
R ¹ _m SiX _4-m (1)
R ² _n SiX _4-n (2)
(R ¹ is an alkyl group having 1 to 8 carbon atoms, X is independently an alkoxy group having 1 to 4 carbon atoms, a halogeno group, an isocyanate group (—N═C═O), a carboxyl group, or a carbon group having 2 to 4 carbon atoms. alkyloxy carboxyl group or alkylamino group having 1 to 4 carbon atoms, m is an integer of 0 to 1 .R ² is alkenyl group having 2 to 8 carbon atoms, acryloxyalkyl group or a carbon number of 4 to 8 carbon atoms A methacryloxyalkyl group of 5 to 8, n represents an integer of 1 to 3. X in formula (1) and X in formula (2) may be the same or different)   When the total of the silicon compound represented by Formula (1) and the silicon compound represented by Formula (2) is 100 mol%, the hydrolyzate and / or hydrolysis condensate is represented by Formula (1). 2. The porous silica fine particle according to claim 1, which is a reaction product of 70 to 99 mol% of a silicon compound and 30 to 1 mol% of a silicon compound represented by the formula (2). It consists of a silicon compound represented by the following formula (1), a silicon compound represented by the following formula (2) and a hydrolyzate and / or hydrolysis condensate of the silicon compound represented by the following formula (3), Porous silica fine particles having a particle size of 5 to 50 nm.
R ¹ _m SiX _4-m (1)
R ² _n SiX _4-n (2)
R ³ _p SiX _4-p (3)
(R ¹ is an alkyl group having 1 to 8 carbon atoms, X is independently an alkoxy group having 1 to 4 carbon atoms, a halogeno group, an isocyanate group (—N═C═O), a carboxyl group, or a carbon group having 2 to 4 carbon atoms. alkyloxy carboxyl group or alkylamino group having 1 to 4 carbon atoms, m is an integer of 0 to 1 .R ² is alkenyl group having 2 to 8 carbon atoms, acryloxyalkyl group or a carbon number of 4 to 8 carbon atoms A methacryloxyalkyl group of 5 to 8, n represents an integer of 1 to ^3. R ³ represents a fluorine-substituted alkyl group having 1 to 12 carbon atoms, and p represents an integer of 1 to ^{3. In} the formula (1), X, X in formula (2) and X in formula (3) may be the same or different)   When the total of the silicon compound represented by the formula (1), the silicon compound represented by the formula (2) and the silicon compound represented by the formula (3) is 100 mol%, the hydrolyzate and / or hydrolyzate The decomposition condensate is 60 to 98 mol% of a silicon compound represented by the formula (1), 1 to 30 mol% of a silicon compound represented by the formula (2), and 1 to 20 silicon compounds represented by the formula (3). The porous silica fine particle according to claim 3, which is a mol% reactant.   The porous silica fine particle according to any one of claims 1 to 4, wherein m is 0 in the silicon compound represented by the formula (1).   The silicon compound represented by the formula (1) and the silicon compound represented by the formula (2) are obtained from water, an alcohol having 1 to 3 carbon atoms, a basic compound, and a half ether of acid amide, diol and diol. The method for producing porous silica fine particles according to any one of claims 1, 2, and 4, wherein the hydrolytic condensation is performed in the presence of at least one selected.   The method for producing porous silica fine particles according to claim 6, wherein the silicon compound represented by the formula (1) is hydrolytically condensed, and then the silicon compound represented by the formula (2) is added and further hydrolytically condensed.   The silicon compound represented by the formula (1), the silicon compound represented by the formula (2), and the silicon compound represented by the formula (3) are mixed with water, an alcohol having 1 to 3 carbon atoms, and a basic compound. The method for producing porous silica fine particles according to any one of claims 3 to 5, wherein the hydrolytic condensation is carried out in the presence of at least one selected from acid amides, diols and diol half ethers.   The porous silica fine particle according to claim 8, wherein the silicon compound represented by the formula (1) is hydrolytically condensed, and then the silicon compound represented by the formula (2) and the formula (3) is added for further hydrolytic condensation. Production method. The silicon compound represented by the following formula (4) is hydrolyzed in the presence of at least one selected from water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols, and half ethers of diols. After the condensation, a silicon compound represented by the following formula (5) and / or a silicon compound represented by the following formula (6) is added to cause hydrolytic condensation, and the average particle size is 5 A method for producing porous silica fine particles of ˜50 nm.
SiX ₄ (4)
R ⁴ _p SiX _4-p (5)
R ⁵ _q SiX _4-q (6)
(R ⁴ is an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an acryloxyalkyl group having 4 to 8 carbon atoms or a methacryloxyalkyl group having 5 to 8 carbon atoms, and X is independently carbon. An alkoxy group having 1 to 4 carbon atoms, a halogeno group, an isocyanate group (—N═C═O), a carboxyl group, an alkyloxycarbonyl group having 2 to 4 carbon atoms or an alkylamino group having 1 to 4 carbon atoms, p is 1 to R represents an integer of 3. R ⁵ represents a fluorine-containing alkyl group having 1 to 12 carbon atoms, q represents an integer of 1 to 3. X in Formula (4), X in Formula (5), and Formula (6) X may be the same or different)   The silicon compound represented by the formula (4) is hydrolyzed and condensed under reaction conditions of 20 to 100 ° C. for 1 to 12 hours, and further the silicon compound and / or the formula (6) represented by the formula (5). The method for producing porous silica fine particles according to claim 10, wherein a silicon compound represented by the formula (1) is added and hydrolytic condensation is performed under reaction conditions of 20 to 100 ° C for 0.5 to 12 hours. In the presence of at least one selected from water, alcohols having 1 to 3 carbon atoms, basic compounds, and acid amides, diols and half ethers of diols, silicon compounds represented by the following formula (4), and the following formulas: After hydrolytic condensation of the silicon compound represented by (5) and / or the silicon compound represented by formula (6), an aprotic organic solvent and pure water or an aqueous acid solution are added, and the aprotic organic solvent is added. A method for producing porous silica fine particles having an average particle diameter of 5 to 50 nm, wherein porous silica particles are extracted into a layer.
SiX ₄ (4)
R ⁴ _p SiX _4-p (5)
R ⁵ _q SiX _4-q (6)
(R ⁴ is an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an acryloxyalkyl group having 4 to 8 carbon atoms or a methacryloxyalkyl group having 5 to 8 carbon atoms, and X is independently carbon. An alkoxy group having 1 to 4 carbon atoms, a halogeno group, an isocyanate group (—N═C═O), a carboxyl group, an alkoxycarbonyl group having 2 to 4 carbon atoms or an alkylamino group having 1 to 4 carbon atoms, p is 1 to 3 R ⁵ represents a fluorine-containing alkyl group having 1 to 12 carbon atoms, q represents an integer of 1 to 3. X in Formula (4), X in Formula (5), and Formula (6) X may be the same or different)   The silicon compound represented by the formula (4), wherein the sum of the silicon compound represented by the formula (4), the silicon compound represented by the formula (5) and the silicon compound represented by the formula (6) is 100 mol%. The method for producing porous silica fine particles according to any one of claims 10 to 12, wherein the hydrolytic condensation is carried out at a ratio of 70 to 99 mol%. The total concentration of the silicon compound represented by formula (4), the silicon compound represented by formula (5) and the silicon compound represented by formula (6) in the reaction solution is 0.5 to 10% by mass. The method for producing porous silica fine particles according to any one of claims 10 to 13 , wherein:   15. The aprotic organic solvent is at least one selected from the group consisting of ester solvents, ether solvents, ketone solvents, and hydrocarbon solvents. Of producing porous silica fine particles.   The method for producing fine porous silica particles according to any one of claims 12 to 15, wherein the acid in the aqueous acid solution is a protonic acid.   The ratio of reaction solution / aprotic organic solvent / pure water or acid aqueous solution is 1 / 0.2 to 2 / 0.1 to 2 (mass ratio). A method for producing porous silica particles according to one item.   The method for producing porous silica particles according to any one of claims 12 to 17, wherein the aprotic organic solvent layer is concentrated after the extraction.   19. The method for producing porous silica particles according to claim 18, wherein an organic solvent having a boiling point higher than that of the aprotic organic solvent is added when the aprotic organic solvent layer is concentrated.   A porous silica fine particle obtained by the production method according to any one of claims 10 to 19.   21. A curable composition comprising the polycrystalline silica fine particles according to any one of claims 1 to 5 and an organic solvent.   21. An antireflection film comprising a low refractive index layer containing the polycrystalline silica fine particles according to any one of claims 1 to 5 and 20.

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