WO2019017305A1

WO2019017305A1 - Coated inorganic fine particle and method for producing same

Info

Publication number: WO2019017305A1
Application number: PCT/JP2018/026576
Authority: WO
Inventors: 田中　聖也; 秀彦飯沼
Original assignee: 関東電化工業株式会社
Priority date: 2017-07-19
Filing date: 2018-07-13
Publication date: 2019-01-24
Also published as: JPWO2019017305A1; TW201908388A; JP7190431B2

Abstract

The purpose of the present invention is to provide: a coated inorganic fine particle suitable for use as a transparent nanocomposite material in optical members, electronic components, coating materials, dental materials, and the like; and a method for producing the coated inorganic fine particle. Provided is a coated inorganic fine particle which has a coating layer and is obtained by reacting at least one among compounds represented by formulae (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2), and salts thereof on the surface of an inorganic fine particle, wherein the inorganic fine particle has an average particle size of at least 1 nm and less than 100 nm, a specific surface area of at least 1 m2/g and less than 3,000 m2/g, and a volatile organic compound content of less than 100 ppm. According to the present invention, a transparent nanocomposite material which is excellent for mass production, and in which inorganic fine particles are uniformly dispersed without aggregation even at high concentrations, can be obtained.

Description

Coated inorganic fine particles and method for producing the same

The present invention relates to coated inorganic fine particles having a coating layer obtained by reacting a specific compound on the surface of inorganic fine particles, and a method for producing the same.

Conventionally, in order to obtain a composite material for which transparency is required, a dispersion liquid in which nano-sized inorganic fine particles are dispersed in a liquid such as an organic solvent is first produced, and then after the dispersion liquid and a resin etc. are mixed. The method of removing the organic solvent is general (see, for example, Patent Documents 1 to 8).
However, in the conventional method, the process of manufacturing the dispersion and removing the organic solvent is energy-wise loaded, and the work efficiency is poor because it includes extra steps.

Moreover, the adhesive agent and light emission which are used for the organic electroluminescence (it may abbreviate as "organic EL" hereafter) which is one of the flat panel displays in the use by which a transparent nanocomposite material is calculated | required A light emitting element is used as a sealing material used for a diode (hereinafter sometimes abbreviated as “LED”) and the like when an adhesive or sealing material is cured by ultraviolet light or heating and outgas is generated by heat generation. It is known that the longevity of the catalyst is adversely affected (see, for example, Patent Documents 9 and 10).

In transparent nanocomposite materials, there is a method of dispersing nanosized inorganic fine particles with a particle size of 20 nm or less directly on solvent-free monomers, oligomers, and resins using a disperser such as a bead mill, but nanosized inorganic fine particles Since the specific surface area is large, the van der Waals force between the particles is strong, and it is difficult to disperse uniformly, and when the viscosity rise occurs in the apparatus, a load is applied and the beads can not be stirred. Further, when inorganic fine particles are dispersed in a resin at a high concentration, transparency can not be obtained, the viscosity of the composite material becomes extremely high, the mixing ratio is limited, and the handling property during molding is adversely affected. Will occur.

In Patent Documents 11 and 12, in order to solve the problem of high viscosity in the composite material by nanoparticle dispersion, particles having a primary particle diameter of 15 nm or less are granulated into a spherical or plate shape of about several tens of μm, and the structure thereof A method is proposed in which particles are surface-coated with a silane coupling agent, mixed with an epoxy or silicone resin and stirred to obtain a transparent composite.
However, in these production methods, even if the crystallite diameter is 15 nm or less, the particle size is about several tens of μm, so application to thin film applications is difficult, and when zirconia spherical particles are dispersed at high concentration in resin There is a problem which adversely affects the transparency and hardness of the composite.

In Patent Document 13, a powder of inorganic oxide fine particles such as ZrO ₂ which is surface-coated and hydrophobized with a carboxylic acid having 4 or more carbon atoms is mixed with a polystyrene resin to obtain a polystyrene composite of high transparency. The surface coating method is first hydrophobized with an aqueous dispersion of inorganic oxide fine particles, and after mixing a non-water-soluble organic solvent such as toluene and a bi-soluble organic solvent such as methanol, water and a bi-soluble organic solvent After evaporation and removal to obtain an inorganic oxide fine particle dispersion liquid of a water-insoluble organic solvent, the water-insoluble organic solvent is evaporated and removed.
However, in this production method, the operation of mixing the non-water-soluble organic solvent and the bi-soluble organic solvent and repeating evaporation and removal is repeated 5 to 6 times, so the operation is complicated and the organic solvent It is difficult to completely remove the organic solvent even after evaporation, because it is used. In addition, since the organic compound to be surface-coated is limited to a carboxylic acid having 4 or more carbon atoms, in the case of a mixture containing one or more kinds of various monomers and resins, it is difficult to combine the compatibility.

In patent document 14, since the zirconia containing epoxy resin composition is obtained by the manufacturing method similar to patent document 13, there exist the same subjects as patent document 13. In addition, zirconia particles synthesized by a wet method as described in Patent Document 14 have low crystallinity, and many impurities such as chloride ions and sulfate ions. Furthermore, since zirconia is synthesized from the zirconia precursor by heat treatment, the particles become bonded or agglomerated particles, which adversely affects the transparency and weatherability of the zirconia-containing epoxy resin composition.

In Patent Document 15, SiO ₂ nanoparticles are heat-treated while being stirred in a monomer solution to form a molecular film derived from a monomer having a film thickness of 1 nm or less on the surface, and then another monomer and a catalyst are added and heated. It is made to crosslink by this and the transparent composite material which consists of a silicone type polymer is proposed.
However, in this production method, compatibility with the silicone-based polymer is important, and the use of SiO ₂ nanoparticles as inorganic fine particles is limited. When other inorganic fine particles are used, they can not be applied because the surface of the particles needs to be coated. In addition, since the refractive index of the SiO ₂ nanoparticles shows a value close to the refractive index of the silicone polymer, transparency is obtained even if the particles are not uniformly dispersed in the resin. In the case of dispersing SiO ₂ nanoparticles at a high concentration or in the case of other inorganic fine particles, it is difficult to maintain transparency.

In addition, Patent Documents 16 to 19 provide a composite material in which a powder of inorganic fine particles surface-coated with a silane coupling agent, methacrylate or the like is directly dispersed in a resin, and a method of producing the same. It is difficult to completely remove the organic solvent because the surface is applied and the organic solvent is removed by evaporation after dispersing the In addition, since a dispersion process using an inorganic fine particle bead mill or the like and a removal process of an organic solvent are required, industrial scale production such as energy load and waste treatment of the organic solvent is difficult.

JP 2003-73558 A Unexamined-Japanese-Patent No. 2006-299126 JP, 2008-156390, A JP, 2009-185185, A JP, 2010-209186, A JP, 2011-79927, A JP, 2014-28873, A JP, 2016-28998, A JP 2005-251631 JP, 2014-201617, A JP 2007-308345 A JP, 2010-6647, A JP 2011-105553 A JP, 2014-221866, A JP 2012-251110 A JP 2008-280443 A JP, 2009-40938, A JP, 2009-74023, A JP 2011-524444 A

The present invention has been made in view of the above circumstances, and provides coated inorganic fine particles suitable for use in transparent nanocomposite materials used for optical members, electronic members, coating materials, dental materials and the like, and a method for producing the same. The purpose is to

The inventors of the present invention conducted intensive studies to solve these problems, and as a result, a coated inorganic particle having a coating layer obtained by reacting a specific compound on the surface of the inorganic particle (hereinafter referred to as "coated inorganic particle" In some cases, the coated inorganic fine particles that satisfy specific conditions and suppress the content of volatile organic compounds are excellent in mass productivity, do not aggregate even at high concentrations, and the inorganic fine particles are uniformly dispersed. The inventors have found that a transparent nanocomposite material can be realized and complete the present invention.
That is, according to the present invention, the following embodiments are provided.
[1] The following formula (A-1), (A-2), (B-1), (B-2), (C), (C-1), and (D-2) on the surface of the inorganic fine particle A coated inorganic fine particle having a coated layer, which is obtained by reacting at least one of a compound represented by any of the above and a salt thereof,
The average particle diameter of the inorganic fine particles is less than 100nm or 1 nm, and a specific surface area of less than ^{1 m} 2 / g or more 3,000 m ² / g,
Coated inorganic fine particles characterized in that the content of volatile organic compounds is less than 100 ppm.

(In the formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2), R ¹ is each independently R ² is a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, R ² is a j-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, or the number of silicon atoms And R ⁵ and R ⁴ each independently represent a structure represented by any one of the following formulas (bc-1) to (bc-6), and R ⁵ is a j-valent (poly) siloxy group of 1 to 20. R ⁶ is a hydrocarbon group having 4 to 30 carbon atoms which may contain a hetero atom, R ⁶ is an n-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, and X ¹ is respectively independently an alkoxy group having 1 to 10 carbon atoms, a hydrogen atom, a chlorine atom, a bromine atom, or iodine atom, X ² and X ³ are each independently Is an alkoxy group having 1 to 10 carbon atoms, an acyloxy group having 1 to 10 carbon atoms which may contain a hetero atom, a chlorine atom, a bromine atom or an iodine atom, and h is an integer of 1 to 4, i Are each independently an integer of 1 to 3, j is an integer of 2 to 10, k is an integer of 1 to 4, l is an integer of 1 to 3, m is an integer of 1 to 3, n is It represents an integer of 2-10. However, an alkoxy group and / or acyloxy groups X ² and X ^3, in combination with other alkoxy groups and / or acyloxy groups X ² and X ³ form a cyclic structure, respectively May be

(In the formulas (bc-1) to (bc-6), R ⁷ each independently represents a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom, and R ⁸ includes a hetero atom R ⁹ may independently be a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms which may contain a hetero atom, or a hetero atom. Represents a hydrocarbon group having 1 to 20 carbon atoms, or a hydrogen atom.)
[2] The coated inorganic fine particles according to [1], wherein the content of the volatile organic compound is 1 ppm or more and less than 80 ppm.
[3] The coated inorganic fine particle according to [1] or [2], which has a refractive index of 1.5 or more.
[4] The coated inorganic fine particle according to any one of [1] to [3], which is at least one selected from the group consisting of metal oxides having a refractive index of 1.5 or more.
[5] The coated inorganic fine particle according to any one of [1] to [4], wherein the inorganic fine particle is at least one selected from the group consisting of zirconium dioxide (ZrO ₂ ) and titanium dioxide (TiO ₂ ) .
[6] [1] to [5], wherein the covering layer is formed by reacting the compound represented by the formula (A-1) or the compound represented by the formula (A-2) ] The coated inorganic fine particle in any one of.
[7] Any one of the above formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2) The coated inorganic fine particles according to any one of [1] to [6], wherein 3 to 100 parts by weight of the compound to be added is added and reacted with 100 parts by weight of the inorganic fine particles.
[8] The coated inorganic fine particles according to any one of [1] to [7], wherein the content of the coating layer is 1% by weight or more and 45% by weight or less.
[9] A preparation step of preparing an aqueous solution in which a metal hydroxide and / or a condensate of the metal hydroxide dissolves and / or disperses, As described above, a hydrothermal reaction step of producing an inorganic fine particle by causing a hydrothermal reaction in a reaction time of 0.1 minutes or more, (3) an isolation step of isolating the inorganic fine particle generated in the hydrothermal reaction step, (4) The inorganic fine particles isolated in the isolation step and the following formula (A-1), (A-2), (B-1), (B-2), (C), (C), (D-1), and A method for producing coated inorganic fine particles, comprising: a coating step of reacting at least one of the compounds represented by any of D-2) in an aqueous solvent.

(In the formulas (bc-1) to (bc-6), R ⁷ each independently represents a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom, and R ⁸ includes a hetero atom R ⁹ may independently be a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms which may contain a hetero atom, or a hetero atom. Represents a hydrocarbon group having 1 to 20 carbon atoms, or a hydrogen atom.)
[10] A nanocomposite material obtained by dispersing the coated inorganic fine particles according to any one of [1] to [8] in a transparent organic compound.
[11] The organic compound is a polymerizable monomer and / or oligomer, and when the monomer and / or oligomer is polymerized, the spectral transmittance of light having a wavelength of 400 nm of the polymer is 65%. The nanocomposite material according to [10], which is the above.
[12] The organic compound is at least one selected from the group consisting of a thermoplastic resin, a thermosetting resin, an ultraviolet curable resin, and an electron beam curable resin, and the spectral transmittance of light having a wavelength of 400 nm is The nanocomposite material of [10] which is 65% or more.
[13] The nanocomposite material according to any one of [10] to [12], wherein the content of the coated inorganic fine particles is 10% by weight or more and 85% by weight or less.

According to the present invention, coated inorganic fine particles can be provided which are excellent in mass productivity, do not aggregate even at high concentrations, and can realize a transparent nanocomposite material in which the inorganic fine particles are uniformly dispersed. In addition, the method for producing the material according to the present invention has a high energy load and poor working efficiency, and can omit the steps of dispersing in an organic solvent and removing the organic solvent, so the production cost is relatively reduced. Useful for the production of

FIG. 1 is a transmission electron microscope (TEM) photograph (200,000 ×) showing the particle form of the zirconia fine particles of 10 nm shown in Production Example 1. FIG. 2 is a transmission electron microscope (TEM) photograph (200,000 ×) showing the particle form of the titania fine particles of 10 nm shown in Production Example 2. FIG. 3 is a transmission electron microscope (TEM) photograph (200,000 ×) showing the particle form of the zirconia fine particles of 10 nm having the coating layer obtained in Example 1. FIG. 4 is a transmission electron microscope (TEM) photograph (200,000 ×) showing the particle form of titania fine particles of 10 nm having the covering layer obtained in Example 10.

MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described based on preferred embodiments, but the present invention is not limited to these descriptions.

<Coated inorganic fine particles>
The coated inorganic fine particles (hereinafter sometimes referred to as "the coated inorganic fine particles of the present invention"), which is an embodiment of the present invention, are provided on the surface of the inorganic fine particles (hereinafter sometimes referred to as "the inorganic fine particles"). A compound represented by any one of formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2) It is a coated inorganic fine particle having a coating layer, which is obtained by reacting at least one kind of the salt (hereinafter sometimes abbreviated as "coating agent"). And, it is characterized in that the average particle diameter of the inorganic fine particles is 1 nm or more and less than 100 nm, the specific surface area is 1 m ² / g or more and 3,000 m ² / g, and the content of volatile organic compound is less than 100 ppm. Do.

(In the formulas (bc-1) to (bc-6), R ⁷ each independently represents a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom, and R ⁸ includes a hetero atom R ⁹ may independently be a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms which may contain a hetero atom, or a hetero atom. Represents a hydrocarbon group having 1 to 20 carbon atoms, or a hydrogen atom.)
The inventors of the present invention can realize a transparent nanocomposite material in which inorganic fine particles are uniformly dispersed, and the above-mentioned coated inorganic fine particles in which the content of volatile organic compound is suppressed have excellent mass productivity and do not aggregate even at high concentration. Found out.
The “inorganic fine particles” in the present invention can be prepared, for example, by hydrothermal reaction under high temperature and high pressure conditions. The inorganic fine particles prepared by the hydrothermal reaction under high temperature and high pressure conditions can be used in any solvent as compared with the conventional solid phase reaction method, wet reaction method, gas phase method, and hydrothermal reaction method under low temperature and low pressure conditions. However, it has the features of excellent dispersibility, uniform particle shape, and large specific surface area. Moreover, since the reactivity of the particle surface is high and reacts uniformly with the "coating agent", it is considered that the volatile organic compound hardly remains. As a result, the compatibility with organic compounds such as monomers, oligomers, and resins is excellent, the powder of inorganic fine particles can be directly dispersed in a solventless organic compound, and the content of volatile organic compounds is small, It is considered that even a transparent nanocomposite hardly generates volatile organic compounds upon curing.
The reaction of the surface of the "inorganic fine particles" with the "coating agent" in the present invention can be carried out, for example, in a water solvent. As a conventional method for surface treatment of inorganic fine particles, the powder of the inorganic fine particles is uniformly dispersed in an organic solvent by a wet dispersing machine such as a bead mill, or the surface is coated with a silane coupling agent while being dispersed. Since the inorganic fine particles are subjected to surface treatment in a state of being crushed or secondary aggregation, it is difficult to uniformly coat the particle surface with the organic compound. Further, in the case of a bead mill, a large amount of organic compound adheres to beads of about several tens of μm to be used, so that precise control is difficult, resulting in an increase in manufacturing cost. Further, if an organic solvent is used in the surface treatment, the organic solvent can not be completely removed even after the drying treatment, and a large amount of volatile organic compound derived from the coating layer of the inorganic fine particles is contained.
That is, the coated inorganic fine particles of the present invention are excellent in dispersibility in any solvent, uniform in particle shape, high in specific surface area, and further prepared to suppress the content of volatile organic compounds. It is inorganic fine particles.
The wavy line in the formulas (bc-1) to (bc-6) means that it is bonded to a titanium atom (Ti) or an aluminum atom (Al) at the end, and the formula (bc-4) is It means that it coordinates to a titanium atom (Ti) or an aluminum atom (Al) by a lone electron pair or the like of a phosphorus atom (P).
Hereinafter, “inorganic fine particles”, “coating agent”, “coating layer”, “volatile organic compound” and the like will be described in detail.

The material and particle shape of the inorganic fine particles are not particularly limited as long as the average particle diameter is “1 nm to less than 100 nm and the specific surface area is 1 m ² / g to 3,000 m ² / g”. And metal oxides, metal hydroxides, metal nitrides, metal carbides, metals and the like, and examples of the particle shape include spheres, cubics, plates, flakes, needles, rods, fibers and the like.
Metal elements of metal oxides, metal hydroxides, metal nitrides, metal carbides, and metals are not limited to one type, and composite metal oxides containing two or more metal elements, composite metal nitrides, composite metal carbides, It may be an alloy or the like.
As metal elements such as metal oxides, metal nitrides, metal carbides and metals,
Periodic table group 1 elements (alkali metal elements) such as lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs);
Periodic Table Group 2 elements (alkaline earth metal elements) such as beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba);
Periodic Table Group 3 elements such as scandium (Sc), yttrium (Y), lanthanoids, actinides;
Periodic table group 4 elements such as titanium (Ti), zirconium (Zr), hafnium (Hf);
Periodic table group 5 elements such as vanadium (V), niobium (Nb), tantalum (Ta), etc.
Periodic table group 6 elements such as chromium (Cr), molybdenum (Mo), tungsten (W);
Periodic table group 7 elements such as manganese (Mn), technetium (Tc) and rhenium (Re);
Periodic table group 8 elements such as iron (Fe), ruthenium (Ru), osmium (Os);
Periodic table group 9 elements such as cobalt (Co), rhodium (Rh), iridium (Ir);
Periodic Table Group 10 elements such as nickel (Ni), palladium (Pd), platinum (Pt);
Periodic Table Group 11 elements such as copper (Cu), silver (Ag), gold (Au), etc.
Periodic table group 12 elements such as zinc (Zn), cadmium (Cd), mercury (Hg);
Periodic Table Group 13 elements such as aluminum (Al), gallium (Ga), indium (In), etc.
The periodic table group 14 elements such as silicon (Si), germanium (Ge), tin (Sn), lead (Pb) and the like can be mentioned.
Examples of the material of the inorganic fine particles include magnesium oxide (MgO), magnesium hydroxide (Mg (OH) ₂ ), calcium oxide (CaO), calcium hydroxide (Ca (OH) ₂ ), aluminum oxide (Al ₂ O ₃ ), Aluminum hydroxide (Al (OH) ₃ ), aluminum hydroxide oxide (AlO (OH)), titanium dioxide (TiO ₂ ), barium titanate (BaTiO ₃ ), manganese oxide (II, III) (Mn ₃ O ₄ ) , Iron oxide (II, III) (Fe ₃ O ₄ ), iron oxide (III) (Fe ₂ O ₃ ), iron hydroxide (FeO (OH)), nickel oxide (II) (NiO), zinc oxide (II) ) (ZnO), yttrium oxide _{_{(III) (Y 2 O 3}} ), zirconium dioxide _(ZrO 2), calcium oxide stabilized zirconium dioxide, oxide Ttoriumu stabilization it is good or zirconium dioxide, zirconium tungstate _(ZrW _{2 O} 8), tungsten oxide (VI) _(WO 3), cerium oxide _{(IV) (CeO 2),} ITO , and the like. Among these, zirconium dioxide (ZrO ₂ ) and titanium dioxide (TiO ₂ ) are particularly preferable.

The “average particle size” of the inorganic fine particles is “1 nm or more and less than 100 nm”, preferably 5 nm or more, preferably 50 nm or less, and more preferably 35 nm or less. When the average particle size of the inorganic fine particles is 1 nm or more, the particle form is uniform and highly dispersed, and when the average particle size exceeds 100 nm, the transparency of the nanocomposite material is significantly reduced.
The “average particle size” of the inorganic fine particles is the average particle size of 200 or more arbitrary particles measured from a TEM image of 30,000 to 200,000 magnifications with a transmission electron microscope (TEM), and the average value It shall mean the figure obtained from

The “specific surface area” of the inorganic fine particles is 1 m ² / g or more and less than 3,000 m ² / g, preferably 15 m ² / g or more, more preferably 20 m ² / g or more, preferably 500 m ² / g It is below. If the specific surface area is smaller than 1 m ² / g, the particle diameter will be large, so the transparency when dispersed in a solvent-free organic compound is poor, and the specific surface area is more than 3,000 m ² / g When the particle size is large, the particle size is small, the dispersibility is poor due to aggregation, and the filling property when dispersed in a solventless organic compound is poor.
In addition, the "specific surface area" of inorganic fine particles shall mean the numerical value of the measurement result by BET method at the time of performing nitrogen gas adsorption at liquid nitrogen temperature.

The inorganic fine particles are preferably metal oxides having a refractive index of 1.5 or more. The refractive index of the inorganic fine particles is more preferably 1.6 or more, still more preferably 2.0 or more.

The coating agent is any one of the following formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2) Although it is at least 1 sort (s) of the compound represented, and its salt, a specific kind is not specifically limited, According to the target coated inorganic fine particle, it can select suitably. Hereinafter, the “formula (A-1), (A-2), (B-1), (B-2), (C), (D-1)), and (D-2), Compounds will be described in detail.

The compound represented by Formula (A-1) and the compound represented by Formula (A-2) are so-called "silane coupling agents" containing a reactive functional group having reactivity such as hydrolysis, The compound represented by the formula (A-1) is a compound having one silyl group, and the compound represented by the formula (A-2) is a compound having a silyl group of 2 to 10.
Further, the compound represented by the formula (A-1) is a description in which the compounds represented by any one of the following formulas (A-1-1) to (A-1-4) are summarized.

The compound represented by the formula (A-2) is a compound represented by the following formula (A-2-1-1), a compound represented by the following formula (A-2-2-1), etc. It is a summary statement.

The compound represented by the formula (B-1) and the compound represented by the formula (B-2) are so-called "titanate coupling agents" containing a reactive functional group having reactivity such as hydrolysis, The compound represented by the formula (B-1) is a compound having one titanate structure, and the compound represented by the formula (B-2) is a compound having two titanate structures.
The compound represented by the formula (C) is a so-called "aluminate coupling agent" containing a reactive functional group having reactivity such as hydrolysis.

The compound represented by the formula (D-1) and the compound represented by the formula (D-2) are “organic acids” having a carboxyl group, and the compound represented by the formula (D-1) is one The compound represented by the formula (D-2) is a compound having a carboxyl group and 2 to 10 carboxyl groups.
Further, the compound represented by the formula (D-2) is a compound in which the compound represented by the following formula (D-2-1), the compound represented by the following formula (D-2-2), etc. is there.

R ^{1 in} formulas (A-1) and (A-2) each independently represents “a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom”; The “hydrogen group” may have each of a branched structure, a cyclic structure, and a carbon-carbon unsaturated bond (carbon-carbon double bond, carbon-carbon triple bond), a saturated hydrocarbon group, an unsaturated carbon It may be any of a hydrogen group, an aromatic hydrocarbon group and the like.
Also, "may contain a hetero atom" means that the hydrogen atom of the hydrocarbon group is substituted with a hetero atom, that is, a monovalent functional group containing a nitrogen atom, an oxygen atom, a sulfur atom, a halogen atom, etc. In addition to the above, it means that the carbon atom inside the carbon skeleton of the hydrocarbon group may be substituted by a divalent or higher functional group (linking group) including nitrogen atom, oxygen atom, sulfur atom, halogen atom, etc. Do.
The carbon atom number of the hydrocarbon group of R ¹ is usually 15 or less, preferably 10 or less, more preferably 8 or less, and when R ¹ is an aromatic hydrocarbon group, the carbon atom number is usually 6 or more .
As a functional group and a linking group contained in R ¹ , an amino group (-N <), an isocyanate group (-NCO), an oxa group (-O-), a carbonyl group (-C (= O)-), an epoxy group , Mercapto group (thiol group, -SH), thia group (-S-), fluoro group (fluorine atom, -F), chloro group (chlorine atom, -Cl), bromo group (bromine atom, -Br), iodo Groups (iodine atom, -I) and the like.
As R ¹ , a methyl group (-CH ₃ , -Me), an ethyl group (-C ₂ H ₅ , -Et), an n-propyl group ( ^-n C ₃ H ₇ , ^-n Pr), an i-propyl group ^{_{_{^{(- i C 3 H 7,}}}} - i Pr), n- butyl ^{_{_{^{(- n C 4 H 9,}}}} - n Bu), t- butyl ^{_{_{^{(- t C 4 H 9,}}}} - t Bu), n- pentyl group ^{_{_{(- n C 5 H 11)}}} , n- hexyl group ^{_{_{^{(- n C 6 H 13,}}}} - n Hex), cyclohexyl ^{_{_{(- c C 6 H 11,}}} -Cy), allyl _(-CH 2 CH = CH ₂ ), vinyl group (-CH = CH ₂ ), phenyl group (-C ₆ H ₅ , -Ph), 3-glycidoxypropyl group, 3-methacryloxypropyl group, 3-acryloxypropyl group, N- And 2- (aminoethyl) -3-aminopropyl group.

“R ² is a C 1 to C 20 j-valent hydrocarbon group which may contain a hetero atom” in the formula (A-2), or “a silicon atom having a C 1 to 20 j-valent (poly) “Siyloxy group” is represented, but “hetero atom may be contained” and “hydrocarbon group” are as defined above, and “j-valent hydrocarbon group” refers to j bonding sites It means having a hydrocarbon group. Further, "(poly) siloxy group" means that it is a siloxy group having 1 silicon atom or a polysiloxy group having 2 to 20 silicon atoms, and -OSi is used for the silicon atom of formula (A-2). Means a (poly) siloxy group attached as The “j-valent (poly) siloxy group” means that it is a (poly) siloxy group having j bonding sites.
The number of carbon atoms of the hydrocarbon group of R ² is usually 15 or less, preferably 10 or less, more preferably 8 or less, and the number of carbon atoms when R ² is an aromatic hydrocarbon group is usually 6 or more .
The number of silicon atoms of the (poly) siloxy group of R ² is usually 15 or less, preferably 10 or less, more preferably 8 or less. The number of carbon atoms of the hydrocarbon group contained in the (poly) siloxy group is usually 15 or less, preferably 10 or less, more preferably 8 or less, as the number of carbon atoms of one hydrocarbon group. The number of carbon atoms in the case of a hydrogen group is usually 6 or more.
As the functional group or linking group contained in R ² , oxa group (—O—), carbonyl group (—C (= O) —), epoxy group, mercapto group (thiol group, —SH), thia group (— S-), fluoro group (fluorine atom, -F), chloro group (chlorine atom, -Cl), bromo group (bromine atom, -Br), iodo group (iodine atom, -I) and the like.
The R ^2, a methylene group _(-CH 2 -), ethylene group _{_{(-C 2 H 4 -),}} n- propylene group ^{_{_{(- n C 3 H 6 -}}} ), i- propylene ^(- _i C 3 _{H 6} -), n-butylene ^{_{_{(- n C 4 H 8 -}}} ), n- pentylene ^{_{_{(- n C 5 H 10 -}}} ), n- hexylene ^{_{_{(- n C 6 H 12 -}}} ), phenylene group (-C ₆ H ₄ -), a methine group (-CH <), dimethylsiloxy group _{_{(-OSi (CH 3) 2 O-}} ), tetramethyldisiloxane siloxy group _{_{(-OSi (CH 3) 2 OSi}} (CH 3) 2 O- Etc.).

R ³ in the formulas (B-1) and (B-2) and R ⁴ in the formula (C) are each independently “one of the following formulas (bc-1) to (bc-6) R ⁷ in the formulas (bc-1) and (bc-2) independently represents “a hydrocarbon group having 11 to 30 carbon atoms which may contain a hetero atom”. However, "may contain a hetero atom" and "hydrocarbon group" are as defined above.

The carbon atom number of the hydrocarbon group of R ⁷ is usually 11 or more, and usually 25 or less, preferably 20 or less.
As the functional group and linking group contained in R ⁷ , oxa group (—O—), carbonyl group (—C (= O) —), mercapto group (thiol group, —SH), thia group (—S—) And fluoro group (fluorine atom, -F), chloro group (chlorine atom, -Cl), bromo group (bromine atom, -Br), iodo group (iodine atom, -I) and the like.
As R ⁷ , n-undecyl group ( ^-n C ₁₁ H ₂₃ ), n-dodecyl group ( ^-n C ₁₂ H ₂₅ ), n-tridecyl group ( ^-n C ₁₃ H ₂₇ ), n-tetradecyl group (- ⁿ C ₁₄ H _29), n- pentadecyl group ^{_{_{(- n C 15 H 31)}}} , n- hexadecyl group ^(- _{n C} 16 _{H 33),} and the like.

R ⁸ in the formula (bc-3) each independently represents “a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom”, but may also contain “a hetero atom "Good" and "hydrocarbon group" are as defined above.
The carbon atom number of the hydrocarbon group of R ⁸ is usually 25 or less, preferably 20 or less, more preferably 10 or less, and when R ⁸ is an aromatic hydrocarbon group, the carbon atom number is usually 6 or more .
As the functional group or linking group contained in R ⁸ , oxa group (—O—), carbonyl group (—C (= O) —), mercapto group (thiol group, —SH), thia group (—S—) And fluoro group (fluorine atom, -F), chloro group (chlorine atom, -Cl), bromo group (bromine atom, -Br), iodo group (iodine atom, -I) and the like.
As R ⁸ , a methyl group (-CH ₃ , -Me), an ethyl group (-C ₂ H ₅ , -Et), an n-propyl group ( ^-n C ₃ H ₇ , ^-n Pr), an i-propyl group ^{_{_{^{(- i C 3 H 7,}}}} - i Pr), n- butyl ^{_{_{^{(- n C 4 H 9,}}}} - n Bu), t- butyl ^{_{_{^{(- t C 4 H 9,}}}} - t Bu), n- pentyl Group ( ^-n C ₅ H ₁₁ ), n-hexyl group ( ^-n C ₆ H ₁₃ , ^-n Hex), cyclohexyl group ( ^-c C ₆ H ₁₁ , -Cy), phenyl group (-C ₆ H ₅ , -Ph) etc.

R ^{9 in} formulas (bc-4) to (bc-6) is each independently “hydroxyl group”, “alkoxy group having 1 to 20 carbon atoms which may contain hetero atom”, “hetero atom And “hydrocarbon group having 1 to 20 carbon atoms” which may contain “,” or “hydrogen atom”, but “may contain a hetero atom” and “hydrocarbon group” It is synonymous. The hydrocarbon group in the "alkoxy group" may have a branched structure, a cyclic structure, and a carbon-carbon unsaturated bond (carbon-carbon double bond, carbon-carbon triple bond), respectively, and is saturated It may be any of a hydrocarbon group, an unsaturated hydrocarbon group, an aromatic hydrocarbon group and the like.
The carbon atom number of the alkoxy group of R ⁹ is usually 15 or less, preferably 10 or less, and when the hydrocarbon group of the alkoxy group of R ⁹ is an aromatic hydrocarbon group, the carbon atom number is usually 6 or more .
The carbon atom number of the hydrocarbon group of R ⁹ is usually 15 or less, preferably 10 or less, and when the hydrocarbon group of R ⁹ is an aromatic hydrocarbon group, the carbon atom number is usually 6 or more.
As R ⁹ , a hydroxyl group (-OH), a methoxy group (-OCH ₃ , -OMe), an ethoxy group (-OC ₂ H ₅ , -OEt), an n-propoxy group (-O ⁿ C ₃ H ₇ ,- O ⁿ Pr), i-propoxy group (-O ⁱ C ₃ H ₇ , -O ⁱ Pr), n-butoxy group (-O ⁿ C ₄ H ₉ , -O ⁿ Bu), t-butoxy group (-O) ^t C ₄ H ₉ , -O ^t Bu), phenoxy group (-OC ₆ H ₅ , -OPh), methyl group (-CH ₃ , -Me), ethyl group (-C ₂ H ₅ , -Et), n - propyl ^{_{_{^{(- n C 3 H 7,}}}} - n Pr), i- propyl ^{_{_{^{(- i C 3 H 7,}}}} - i Pr), n- butyl ^{_{_{^{(- n C 4 H 9,}}}} - n Bu), t- butyl ^{_{_{^{(- t C 4 H 9,}}}} - t Bu), n- pentyl ^{_{_{(- n C 5 H 11)}}} , n- f Sill group ^{_{_{^{(- n C 6 H 13,}}}} - n Hex), cyclohexyl ^{_{_{(- c C 6 H 11,}}} -Cy), phenyl group _{_{(-C 6 H 5, -Ph)}} , such as a hydrogen atom.

R ⁵ in the formula (D-1) each independently represents “a hydrocarbon group having 4 to 30 carbon atoms which may contain a hetero atom”, but may also contain “a hetero atom "Good" and "hydrocarbon group" are as defined above.
The carbon atom number of the hydrocarbon group of R ⁵ is usually 25 or less, preferably 20 or less, more preferably 10 or less, and the carbon atom number when R ⁵ is an aromatic hydrocarbon group is usually 6 or more .
As the functional group and linking group contained in R ⁵ , oxa group (—O—), carbonyl group (—C (= O) —), mercapto group (thiol group, —SH), thia group (—S—) And fluoro group (fluorine atom, -F), chloro group (chlorine atom, -Cl), bromo group (bromine atom, -Br), iodo group (iodine atom, -I) and the like.
As R ⁵ , n-butyl ( ^-n C ₄ H ₉ , ^-n Bu), t-butyl ( ^-t C ₄ H ₉ , ^-t Bu), n-pentyl ( ^-n C ₅ H ₁₁₎ ), n-hexyl group ^{_{_{^{(- n C 6 H 13,}}}} - n Hex), cyclohexyl ^{_{_{(- c C 6 H 11,}}} -Cy), phenyl group _(-C ₆ H 5, -Ph), and the like.

R ⁶ in the formula (D-2) represents “n-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom”, but may also contain a hetero atom And “hydrocarbon group” are as defined above, and “n-valent hydrocarbon group” means a hydrocarbon group having n bonding sites.
The carbon atom number of the hydrocarbon group of R ⁶ is usually 15 or less, preferably 10 or less, more preferably 8 or less, and the carbon atom number when R ⁶ is an aromatic hydrocarbon group is usually 6 or more .
As the functional group or linking group contained in R ⁶ , oxa group (—O—), carbonyl group (—C (= O) —), thia group (—S—), fluoro group (fluorine atom, —F) And chloro group (chlorine atom, -Cl), bromo group (bromine atom, -Br), iodo group (iodine atom, -I) and the like.
The R ^6, a methylene group _(-CH 2 -), ethylene group _{_{(-C 2 H 4 -),}} n- propylene group ^{_{_{(- n C 3 H 6 -}}} ), i- propylene ^(- _i C 3 _{H 6} -), n-butylene ^{_{_{(- n C 4 H 8 -}}} ), n- pentylene ^{_{_{(- n C 5 H 10 -}}} ), n- hexylene ^{_{_{(- n C 6 H 12 -}}} ), phenylene group (-C ₆ H ₄ -), and the like.

X ^{1 in} formulas (A-1) and (A-2) is each independently an “alkoxy group having 1 to 10 carbon atoms”, a “hydrogen atom”, a “chlorine atom”, a “bromine atom”, or Although "iodine atom" is represented, "alkoxy group" is as defined above.
The carbon atom number of the alkoxy group of X ¹ is usually 8 or less, preferably 6 or less, more preferably 3 or less, and the carbon atom number when the hydrocarbon group of the alkoxy group of X ¹ is an aromatic hydrocarbon group is , Usually 6 or more.
As X ¹ , a methoxy group (-OCH ₃ , -OMe), an ethoxy group (-OC ₂ H ₅ , -OEt), an n-propoxy group (-O ⁿ C ₃ H ₇ , -O ⁿ Pr), i- Propoxy group (-O ⁱ C ₃ H ₇ , -O ⁱ Pr), n-butoxy group (-O ⁿ C ₄ H ₉ , -O ⁿ Bu), t-butoxy group (-O ^t C ₄ H ₉ ,- O ^t Bu), phenoxy group (-OC ₆ H ₅ , -OPh), hydrogen atom, chlorine atom, bromine atom, iodine atom can be mentioned. Among these, alkoxy groups such as methoxy and ethoxy are preferable. When X ¹ is an alkoxy group, volatile organic compounds such as methanol and ethanol are produced by the reaction, and the effect of the present invention can be more effectively utilized.

X ² and X ³ in the formulas (B-1), (B-2) and (C) are each independently “an alkoxy group having 1 to 10 carbon atoms”, “even if it contains a hetero atom” Represents a good acyloxy group having 1 to 10 carbon atoms, "chlorine atom", "bromine atom" or "iodine atom", but "may contain a hetero atom" and "alkoxy group" are as described above It is synonymous with Further, “acyloxy group” means a structure represented by —OC (= O) R, and the hydrocarbon group in the acyloxy group has a branched structure, a cyclic structure, and a carbon-carbon unsaturated bond (carbon-carbon disaccharide). Each may have a heavy bond and a carbon-carbon triple bond, and may be any of a saturated hydrocarbon group, an unsaturated hydrocarbon group, an aromatic hydrocarbon group and the like. Further "alkoxy group and / or acyloxy groups X ² and X ^3, other alkoxy groups and / or forming a cyclic structure bonded to the acyloxy group respectively X ² and X ³ 'and to that structure, alkoxy It means that the hydrocarbon groups of the group and the acyloxy group are combined to form a cyclic structure (see below). The number of carbon atoms of the hydrocarbon group when forming a cyclic structure is such that the total number of carbon atoms is 1 to 10.

The number of carbon atoms of the alkoxy group and acyloxy group of X ² and X ³ is usually 8 or less, preferably 6 or less, more preferably 3 or less, and the hydrocarbon group of the alkoxy group of X ² and X ³ and acyloxy group is The number of carbon atoms in the case of an aromatic hydrocarbon group is usually 6 or more.
As the functional group or linking group contained in X ² and X ³ , oxa group (—O—), carbonyl group (—C (= O) —), thia group (—S—), fluoro group (fluorine atom, -F), chloro group (chlorine atom, -Cl), bromo group (bromine atom, -Br), iodo group (iodine atom, -I) and the like.
As X ² and X ³ , a methoxy group (-OCH ₃ , -OMe), an ethoxy group (-OC ₂ H ₅ , -OEt), and an n-propoxy group (-O ⁿ C ₃ H ₇ , -O ⁿ Pr) , I-propoxy group (-O ⁱ C ₃ H ₇ , -O ⁱ Pr), n-butoxy group (-O ⁿ C ₄ H ₉ , -O ⁿ Bu), t-butoxy group (-O ^t C ₄ H) _9, ^-O t Bu), phenoxy group _{_{(-OC 6 H 5, -OPh)}} , an acetyl group, an acetyl acetonate group, a chlorine atom, a bromine atom, an iodine atom. Among these, alkoxy groups such as methoxy and ethoxy, and acyloxy groups such as acetyl and acetylacetonate are preferable. When X ¹ is an alkoxy group or an acyloxy group, volatile organic compounds such as methanol, ethanol and acetylacetone are produced by the reaction, and the effect of the present invention can be more effectively utilized.

The coating agent may be any one of the formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1) and (D-2). And at least one of its salts, the term "salts thereof" means compounds of formulas (A-1), (A-2), (B-1), (B-2), (C), ( It means a salt formed by the compound represented by any of D-1) and (D-2). For example, a compound represented by any one of formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2) When it has a basic functional group such as an amino group, it may combine with hydrogen chloride (HCl) to form a hydrochloride, and organic acids such as compounds represented by formula (D-1) are alkali metals. May form metal salts with cations such as The coating may be such a salt.

As a compound represented by Formula (A-1) and a compound represented by Formula (A-2), vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ) Ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryl Trimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl) -3 -Aminopropylmethyl Methoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl) -Butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane, 3 -Mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanatepropyltriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane Silane, propyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, phenyltrimethoxysilane, trifluoropropyltrimethoxysilane, cyclohexylmethyldimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane Examples include ethoxysilane, hexyltriethoxysilane, hexamethyldisilazane and the like.

Examples of the compound represented by the formula (B-1) and the compound represented by the formula (B-2) include tetraisopropyl titanate, tetranormal butyl titanate, titanium butoxide dimer, tetra-2-ethylhexyl titanate, titanium di-2 -Ethylhexoxybis (2-ethyl-3-hydroxyhexoxide), isopropyltriisostearoyl titanate, isopropyltris (dioctyl pyrophosphate) titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, tris (dioctyl pyrophosphate) ethylene Titanate, isopropyl dioctyl pyrophosphate titanate, isopropyl tris (dodecylbenzenesulfonyl) titanate, tetraisopropyl bis (dioctyl phosphite) B) Titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate and the like.

Examples of the compound represented by the formula (C) include alkylacetoacetate aluminum diisopropylate, aluminum trisecondary butoxide, aluminum tris (acetylacetonate), aluminum bisethylacetoacetate monoacetylacetonate, aluminum tris (ethylacetoacetate) And aluminum alkyl acetoacetate diisopropylate.

As a compound represented by Formula (D-1) and a compound represented by Formula (D-2), butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, lauric acid, Examples thereof include organic acids such as tetradecanoic acid, pentadecanoic acid, palmitic acid, margaric acid, stearic acid, oleic acid, acetic acid, linoleic acid, linolenic acid and the like.

The coated inorganic fine particle of the present invention is a coated inorganic fine particle having a coated layer obtained by reacting a coating agent on the surface of the inorganic fine particle, but the amount of the coating agent added in the reaction is 100 parts by weight of the inorganic fine particle. On the other hand, the amount is usually 3 parts by weight or more, preferably 5 parts by weight or more, and usually 100 parts by weight or less, preferably 55 parts by weight or less. When the amount of the coating agent added is less than 3 parts by weight, the coated inorganic fine particles are difficult to uniformly disperse in the solvent-free organic compound and include secondary aggregation particles. When the coating amount of the organic compound is larger than 100 parts by weight, uniform dispersion is possible, but the proportion of the coating agent is larger than that of the inorganic fine particles, and the original function of the inorganic fine particles is degraded.

The coating layer of the coated inorganic fine particles of the present invention means a layer formed by the reaction of the coating agent (surface modification) on the surface of the inorganic fine particles or the reaction between the coating agents and adsorption on the surface of the inorganic fine particles. The composition is derived from the type of coating agent.
The content of the coating layer in the coated inorganic fine particles of the present invention (when the entire coated inorganic fine particles is 100% by weight) is usually 1% by weight or more, preferably 3% by weight or more, and usually 45% by weight or less, preferably It is 30% by weight or less. When the coating layer is less than 1% by weight, the coated inorganic fine particles are difficult to uniformly disperse in the solvent-free organic compound, and include secondary aggregation particles. When the coating layer is larger than 45% by weight, uniform dispersion is possible, but the proportion of the coating layer is larger than that of the inorganic fine particles, and the original function of the inorganic fine particles is degraded.
The content of the covering layer can be determined by quantifying the amounts of silicon element, titanium element, aluminum element, organic group and the like contained in the covering layer by various elemental analysis and the like.

The content of volatile organic compounds in the coated inorganic fine particles of the present invention is less than 100 ppm, but "volatile organic compounds" means heating at 120 ° C for 10 minutes, including the main VOC 100 species shown by the Ministry of the Environment It means an amount of all organic compounds that volatilize at the same time, and the total volatile organic compounds generated when the coated inorganic fine particles are heated at 120 ° C. for 10 minutes are measured as a volume concentration in terms of toluene.
Volatile organic compounds include alcohols such as methanol, ethanol, n-propanol and i-propanol produced by decomposition of coating agent, etc .; hydrocarbon solvents such as hexane, cyclohexane, toluene, xylene, ethylbenzene and decane; dichloromethane, trichloroethylene And halogen solvents such as tetrachloroethylene; ether solvents such as tetrahydrofuran; ester solvents such as ethyl acetate; and siloxane compounds such as decamethylcyclopentasiloxane produced by condensation of a coating agent.

The content of the volatile organic compound is usually 1 ppm or more, preferably less than 80 ppm, more preferably less than 50 ppm. When the volatile organic compound is 100 ppm or more, outgassing occurs when curing the nanocomposite material, which adversely affects the life of the light emitting element in applications such as organic EL and LED. Moreover, a drying process etc. are needed for removal of a volatile organic compound at the time of shaping | molding processing, and the increase in manufacturing cost is caused.
In addition, content of a volatile organic compound can be measured using a commercially available volatile organic compound measuring apparatus.

The coated inorganic fine particles of the present invention are preferably metal oxides having a refractive index of 1.5 or more. The refractive index of the coated inorganic fine particles of the present invention is preferably 1.5 or more, more preferably 1.6 or more, and still more preferably 2.0 or more. When used for transparent nanocomposite materials such as liquid crystal displays, organic EL, LEDs, and optical members such as lenses, if the refractive index is less than 1.5 like SiO ₂ , it is equivalent to the refractive index of organic compounds such as resin or It is difficult to adjust the refractive index because it becomes lower.

<Method of producing coated inorganic fine particles>
The method for producing the coated inorganic fine particles of the present invention is not particularly limited, but preferred methods include the following steps (1) to (4). The method for producing coated inorganic fine particles, which comprises the steps of (1) to (4), is also an aspect of the present invention.
(1) A preparation step of preparing an aqueous solution in which a metal hydroxide and / or a condensate of the metal hydroxide dissolves and / or disperses (hereinafter, may be abbreviated as "preparation step")
(2) A hydrothermal reaction process (hereinafter referred to as “hydrothermal reaction process”) in which the aqueous solution prepared in the preparation process is subjected to a hydrothermal reaction at a temperature of 200 ° C. or more, a pressure of 20 MPa or more, and a reaction time of 0.1 minutes or more Sometimes it may be abbreviated.)
(3) The isolation process (it may abbreviate as the "isolation process" hereafter) which isolates the said inorganic fine particle produced | generated at the hydrothermal reaction process.
(4) The inorganic fine particles isolated in the isolation step and the formulas (A-1), (A-2), (B-1), (B-2), (C), (C), (D-1), And a coating step in which at least one of the compounds represented by (D-2) is reacted in an aqueous solvent (hereinafter sometimes referred to as "coating step")
Hereinafter, the "preparation step", the "hydrothermal reaction step", the "isolation step", the "coating step" and the like will be described in detail.

(Preparation process)
In the preparation step, an aqueous solution (hereinafter referred to as “metal hydroxide” and / or “a condensate of metal hydroxide” (hereinafter sometimes abbreviated as “metal hydroxide etc.”) is dissolved and / or dispersed. (Sometimes abbreviated as “aqueous solution such as metal hydroxide”), but “metal hydroxide” is a metal hydroxide material precursor that grows into particles on inorganic fine particles, “metal hydroxide "Condensate of substance" means a precursor in a state in which metal hydroxides are condensed to form M—O—M (metal atom-oxygen atom-metal atom) bond. Further, the “aqueous solution” is not limited to the state in which the metal hydroxide or the like is uniformly dispersed (dissolved) at the molecular level, and includes the state of a suspension (slurry).
That is, even if the metal hydroxide is dissolved in the form of a monomer, the inorganic fine particle precursor is in a state in which the metal hydroxide is aggregated (hereinafter, “aggregate of metal hydroxide”) Or may be dispersed (suspended), or the condensate of a metal hydroxide may be dispersed (suspended) or may be in a mixed state. means.
The type of metal element such as metal hydroxide should be selected according to the type of target inorganic fine particle, and when the target inorganic fine particle is a composite metal oxide or alloy, etc., two types can be selected. The above metal elements should be selected.
The aggregate of metal hydroxide and the condensate of metal hydroxide may be crystalline or amorphous (amorphous substance), but nucleation and particles in a uniform state are possible. It is preferably amorphous from the viewpoint of growth. In addition, when the aggregate of a metal hydroxide and the condensate of a metal hydroxide have crystallinity, it is preferable that the average particle diameter is 0.1 micrometer or less. If the particle size exceeds 0.1 μm or less, it is difficult to disperse metal hydroxide etc. uniformly and precipitate in the hydrothermal reaction step, resulting in non-uniform reaction, so the particle size and particle shape are uniform. Therefore, it is difficult to obtain highly dispersible, highly crystalline inorganic fine particles. Moreover, when metal hydroxide etc. precipitate, clogging in a reactor tends to occur.

The concentration of the metal oxide or the like in the aqueous solution such as the metal hydroxide is usually 0.01 mol / L or more, preferably 0.05 mol / L or more, preferably 0.1 mol / L, as the substance mass of the metal element (main component element). It is L or more, usually 1.0 mol / L or less, preferably 0.5 mol / L or less. The concentration of the metal hydroxide and / or the condensate of the metal hydroxide greatly affects the viscosity of the aqueous solution, and if it exceeds 1.0 mol / L, the high viscosity tends to clog the product in the reactor, Insufficient yield and contamination.

Although the preparation method of aqueous solutions, such as a metal hydroxide, is not specifically limited, The method of hydrolyzing the raw material compound containing the target metal element as an preparation method in acidic or basic aqueous solution is mentioned. In particular, a method is preferable in which a base is added to an aqueous solution in which a starting compound is dissolved and / or dispersed (hereinafter sometimes referred to as "an aqueous solution of a starting compound") for hydrolysis. When the raw material compound is an acidic compound having Lewis acidity or the like, "neutralization" is usually performed by adding a base to an aqueous solution.
The raw material compound is not particularly limited as long as it contains a target metal element and metal hydroxide and the like are generated by hydrolysis, but metal chloride, metal sulfate, metal nitrate and the like containing the target metal element And metal hydroxides, metal alkoxides, metal hydroxides, etc.
The concentration of the raw material compound in the aqueous solution can be appropriately selected according to the type of metal element etc., but is usually 0.05 mol / L or more, preferably 0.1 mol / L or more, and usually 3.0 mol / L Below, Preferably it is 0.5 mol / L or less.
As a base, sodium hydroxide (NaOH), potassium hydroxide (KOH), ammonia (NH ₃ ), ammonium hydrogencarbonate (NH ₄ HCO ₃ ), sodium carbonate (Na ₂ CO ₃ ), potassium carbonate (K ₂ CO ₃₎ And sodium hydrogen carbonate (NaHCO ₃ ), potassium hydrogen carbonate (KHCO ₃ ) and the like, and two or more kinds can be used in combination. The base is preferably dissolved in water and added to the aqueous solution of the starting compound in the form of a basic aqueous solution (alkaline aqueous solution).
The addition amount of the basic aqueous solution is preferably such that the pH at the end of the addition is 3.0 to 14.0, and more preferably 6.0 to 13.0. Further, the weight ratio (the former: the latter) of the preferable addition amount of the basic aqueous solution and the aqueous solution of the raw material compound is 100: 1 to 1: 100, and particularly preferably 10: 1 to 1:10.

A dispersing agent may be added to the liquid phase of the aqueous solution and / or basic aqueous solution of the starting compound in order to obtain a uniform state. As a dispersing agent, organic compounds, such as surfactant, a citric acid, an amine, an organic solvent, polyethyleneglycol (PEG), or polyvinyl alcohol (PVA), are mentioned, for example. When these dispersants are added, in addition to the improvement of the dispersibility in the inorganic fine particles, the effects of control of the particle form and high crystallization are also exhibited. Among such dispersants, surfactants are particularly preferable because they can further improve the dispersibility and the effect on the uniformity to the particle form is large. As the surfactant, for example, higher fatty acids and salts thereof, alkyl sulfate ester salts, fatty acid amine compounds, alkyl sulfosuccinates and the like can be used.
The amount of the dispersant to be added is usually 0.01% by weight or more, preferably 0.1% by weight or more, and usually 10.0% by weight or less, preferably 5% by weight based on the theoretical amount of the inorganic fine particles to be aimed. .0 wt% or less. If the amount of the dispersant added is less than 0.01% by weight, there is little effect on homogenization of the inorganic alkali salt aqueous solution or slurry by the dispersant and high dispersibility, high crystallinity and high homogeneity of the formed inorganic fine particles, When it exceeds 10.0% by weight, the produced inorganic fine particles are easily aggregated.

(Hydrothermal reaction process)
The hydrothermal reaction step is a step of hydrothermally reacting the aqueous solution prepared in the preparation step at a temperature of 200 ° C. or more, a pressure of 20 MPa or more, and a reaction time of 0.1 minutes or more to generate inorganic fine particles. The inorganic fine particles produced by satisfying the condition of “pressure 20 MPa or more, reaction time 0.1 minutes or more” are the conventional solid phase reaction method, wet reaction method, gas phase method, hydrothermal reaction method under low temperature and low pressure condition Compared to the above, it has excellent dispersibility in any solvent, uniform particle shape, large specific surface area, and high reactivity on the particle surface.
The temperature of the hydrothermal reaction is 200 ° C. or more, preferably 250 ° C. or more, and usually 450 ° C. or less, preferably 400 ° C. or less. The temperature of the hydrothermal reaction varies depending on the particles to be produced, but if the temperature is less than 200 ° C. as with the pressure, particle formation is difficult, the crystallinity is poor, and impurities derived from the raw material are easily taken up. The upper limit of the temperature is not particularly limited and is limited to the specifications of the apparatus, but if it exceeds 500 ° C. like the pressure, the product tends to adhere within the reaction tube, leading to a decrease in yield and contamination. .

[Correction based on rule 91 31.07.218]
The pressure of the hydrothermal reaction is 20 MPa or more, but is usually 50 MPa or less, preferably 40 MPa or less. The pressure of the hydrothermal reaction varies depending on the particles to be produced, but if it is less than 20 MPa, particle formation is difficult, the crystallinity is poor, and impurities derived from the raw material are easily taken in. The upper limit of the pressure is not particularly limited and is limited to the specification of the apparatus, but if it exceeds 50 MPa, the product tends to adhere within the reaction tube, resulting in a decrease in yield and contamination.

The reaction time of the hydrothermal reaction (residence time in the reactor) is 0.1 minutes or more, but is usually 60 minutes or less, preferably 30 minutes or less. The reaction time varies depending on the particles to be produced, but when it is less than 0.1 minutes, particle formation is difficult, the crystallinity is poor, and impurities derived from the raw material are easily taken up.

The hydrothermal reaction step is not particularly limited as long as it satisfies the conditions described above, but in the case of producing metal fine particles as inorganic fine particles, for example, the reaction is performed in the presence of a reducing agent such as hydrogen gas, It can be mentioned to proceed with the reduction reaction. In addition to this, various types of inorganic fine particles can be generated by appropriately controlling the conditions of the hydrothermal reaction step. Further, depending on the conditions, control of particle shapes such as spherical, cubic, plate, flake, needle, rod, and fiber is possible.

(Isolation process)
The isolation step is a step of isolating the inorganic fine particles generated in the hydrothermal reaction step, but the isolation method is not particularly limited, and a known method can be appropriately adopted. Usually, the aqueous solution which has finished the hydrothermal process is cooled, depressurized and recovered, and the recovered product is filtered, washed with water and dried.

(Coating process)
The coating step is a step in which the inorganic fine particles isolated in the isolation step and the coating agent are reacted in a water solvent, but by being carried out "in water solvent", compared with the case where an organic solvent is used, It is characterized in that volatile organic compounds do not easily remain and that the coating agent can be easily coated uniformly on the surface of the inorganic fine particles.
The operation method of the coating step is not particularly limited, but usually, after uniformly dispersing the inorganic fine particles in the water solvent, a coating agent is added, and the reaction is performed by heating to the reaction temperature.

The amount of the water solvent used in the coating step is such that the concentration of the inorganic fine particles is usually 1% by weight or more, preferably 3% by weight or more, more preferably 5% by weight or more, and usually 45% by weight or less, preferably 35% by weight or less More preferably, it is used in an amount of 25% by weight or less.
In order to uniformly disperse the inorganic fine particles in the water solvent, it is preferable to adjust the pH by adding an acid or a base. The acid or base is preferably added so as to give a pH of 1.0 to 14.0 at the time of addition, more preferably 3.0 to 10.0.
In order to disperse the inorganic fine particles uniformly in the water solvent, it is preferable to carry out stirring using a dispersing machine such as an ultrasonic homogenizer, a planetary ball mill, a Henschel mixer, a colloid mill, a wet jet mill, a wet bead mill.

The amount of the coating agent added is usually 3 parts by weight or more, preferably 5 parts by weight or more, and usually 100 parts by weight or less, preferably 55 parts by weight or less, based on 100 parts by weight of the inorganic fine particles.

The temperature of the reaction in the coating step is usually room temperature or more, preferably 25 ° C. or more, and usually 80 ° C. or less, preferably 60 ° C. or less.
The reaction time (retention time in the reactor) of the coating step is 5 minutes or more, but is usually 24 hours or less, preferably 8 hours or less.

The method for producing coated inorganic fine particles of the present invention may include those other than the above-mentioned preparation step and the like, and usually, the suspension after the covering step is dried and crushed in a temperature range of 200 ° C. or less. Thus, coated inorganic fine particles are obtained.

<Nano composite material>
Although the coated inorganic fine particles of the present invention are described above as being useful for realizing a transparent nanocomposite material, a nanocomposite material obtained by dispersing the coated inorganic fine particles of the present invention in a transparent organic compound The present invention may be abbreviated as “the nanocomposite material of the present invention” is also an aspect of the present invention.
Hereinafter, the "transparent organic compound" and the like will be described in detail.

The nanocomposite material of the present invention is a material obtained by dispersing the coated inorganic fine particles of the present invention in a transparent organic compound, and as the organic compound, an organic solvent; a polymerizable monomer, an oligomer, such as polyethylene, polypropylene, Thermosetting resins such as polystyrene, acrylic, polyvinyl chloride, polycarbonate, nylon, urethane, PBT, PET, thermoplastic resins such as ABS, melamine, phenol, epoxy, urethane, polyimide, diallyl phthalate, unsaturated polyester, furan, silicone, etc. Examples thereof include resins, elastomers, rubbers, radically curable or cationically polymerizable ultraviolet curable resins, and curable resins such as visible light, infrared light, and electron beams. It may be used alone or in combination, and the nanocomposite material can be appropriately selected according to the application.

The nanocomposite material of the present invention is preferably "transparent". Note that “transparent” may be anything that transmits light of a predetermined wavelength band such as visible light, near infrared light, near ultraviolet light, etc. Specifically, the spectral transmittance of light with a wavelength of 400 nm is 65% or more Is preferably, and more preferably 85% or more. In applications such as optical members, if the spectral transmittance is less than 65%, it is not preferable because it directly affects the performance deterioration of the optical device. In addition, even in applications other than optical members and the like, a uniform dispersed state of inorganic fine particles in which the transmittance is 65% or more is required.

The content of the coated inorganic fine particles in the nanocomposite material of the present invention is usually 10% by weight or more, preferably 20% by weight or more, and usually 85% by weight or less, preferably 75% by weight or less. When the content of the coated inorganic fine particles is less than 10% by weight, it is difficult to express the functionality of the inorganic fine particles. If the content of the coated inorganic fine particles is more than 85% by weight, the inherent functionality of the organic compound can not be exhibited, and the viscosity of the composite material becomes extremely high, which adversely affects the handling during molding.

In order to uniformly disperse the coated inorganic fine particles of the present invention in an organic compound, a ribbon mixer, a conea, an extruder, an internal mixer, a kneader, a pug mill, a gap compounder, an auger, a pin mixer, a rod mixer, a sand mill, a clutcher High-speed flow mixer, Henschel mixer, Shuggie mixer, Simpson mill, Whirl mix, Eirich mill, universal mixer, grinding machine, planetary mixer, 3-roll mill, taper roll mill, kneader, wet bead mill, wet jet mill It is desirable to use a dispersing machine such as an ultrasonic homogenizer, a high speed stirring type or a pressure type emulsifier, a stirrer, or a mixer. During the dispersion process, the viscosity can be reduced or defoamed by heating or vacuum to make the dispersion more uniform.

In the nanocomposite material of the present invention, various types of additives may be used alone or in combination, as required. Additives include heat stabilizers, antioxidants, light resistance stabilizers, weathering stabilizers, stabilizers for ultraviolet light absorption and near infrared light absorption, lubricants, plasticizers, white turbidity inhibitors, dispersants, colorants, antistatic agents Flame retardants, mold release agents, curing agents, initiators and the like.
The shape of the nanocomposite material of the present invention can be appropriately selected depending on the application, such as liquid, bulk, film, sheet, and thin film.

EXAMPLES Hereinafter, the coated inorganic fine particles of the present invention and the method for producing the same will be described by way of examples, but the present invention is not limited to these examples.

[Production example 1 (zirconia fine particles)]
Using an aqueous solution of zirconium oxychloride as an aqueous solution of zirconium salt and an aqueous solution of sodium hydroxide as an aqueous alkali solution, the amount of Zr is 0.40 mol and the amount of alkali is 0.8 mol [degree of neutralization = alkali amount / (2 × Zr amount) = 1 The ingredients were prepared to be .0]. Next, in a raw material tank, an aqueous solution of sodium hydroxide was added to an aqueous solution of zirconium salt at room temperature and under the atmosphere to prepare an amorphous zirconium hydroxide-containing aqueous solution as a reaction precursor. The pH value of the reaction precursor after preparation was 12.5. The prepared reaction precursor was subjected to a hydrothermal reaction in a hydrothermal reaction apparatus at a temperature of 300 ° C., a pressure of 20 MPa, and a residence time of 0.25 minutes, and then filtered, washed with water and dried to obtain zirconia fine particles.
The obtained zirconia fine particles evaluated the average particle diameter and the specific surface area. Further, a transmission electron microscope (TEM) photograph (200,000 ×) is shown in FIG. The average particle size was 10 nm, the relative standard deviation of the average particle size was 0.20, and the specific surface area was 140 m ² / g. The uniformity of particle shape is good from observation by TEM.

[Production Example 2 (Titania fine particles)]
Using titanium tetrachloride aqueous solution as titanium salt aqueous solution and sodium hydroxide aqueous solution as alkaline aqueous solution, the amount of Ti is 0.40 mol, the amount of alkali is 1.2 mol [degree of neutralization = alkali amount / (4 × amount of Ti) = 1 The ingredients were prepared to be .0]. Next, in the raw material tank, an aqueous solution of nitric acid was added to the aqueous solution of titanium salt at room temperature and under the atmosphere to prepare an amorphous titanium hydroxide-containing aqueous solution as a reaction precursor. The pH value of the reaction precursor after preparation was 5.0. The prepared reaction precursor was subjected to a hydrothermal reaction in a hydrothermal reaction apparatus at a temperature of 350 ° C. and a pressure of 20 MPa for a residence time of 0.25 minutes, and then filtered, washed with water and dried to obtain 10 nm titania fine particles.
The obtained titania fine particles were evaluated for average particle size and specific surface area. Further, a transmission electron microscope (TEM) photograph (200,000 ×) is shown in FIG. The average particle size was 10 nm, the relative standard deviation of the average particle size was 0.24, and the specific surface area was 160 m ² / g. The uniformity of particle shape is good from observation by TEM.

[Preparation of coated inorganic fine particles]
<Examples 1 to 9>
In 2700 g of water, 300 g of the zirconia fine particles of Production Example 1 was dispersed, 24 g of acetic acid was added, and uniformly dispersed. While stirring the aqueous dispersion, the organosilicon compound was added according to Table 1 and stirred at 50 ° C. for 4 hours. Thereafter, the mixed dispersion was dried at 80 ° C. to obtain an organic silicon compound-coated zirconia fine particle.

Example 10
In 2700 g of water, 300 g of the titania fine particles of Production Example 2 was dispersed, 24 g of acetic acid was added, and uniformly dispersed. While stirring the aqueous dispersion, the organosilicon compound was added according to Table 1 and stirred at 50 ° C. for 4 hours. Thereafter, the mixed dispersion was dried at 80 ° C. to obtain an organic silicon compound-coated titania fine particle.

Comparative Example 1
300 g of the zirconia fine particles of Preparation Example 1 were uniformly dispersed in 2700 g of ethanol. While stirring this ethanol dispersion, 66.9 g of 3-methacryloxypropyltrimethoxysilane ("A-174" manufactured by Momentive Performance Materials, Inc.) was added, and the mixture was stirred at 50 ° C for 4 hours. Thereafter, the mixed dispersion was dried under reduced pressure at 60 ° C. to obtain zirconia fine particles coated with an organosilicon compound.

Comparative Example 2
In 2700 g of water, 300 g of commercially available zirconia fine particles synthesized by a wet method and having an average particle diameter of 15 nm and a specific surface area of 90 m ² / g were dispersed, and 24 g of acetic acid was added to achieve uniform dispersion. While the aqueous dispersion was stirred, 66.9 g of 3-methacryloxypropyltrimethoxysilane ("A-174" manufactured by Momentive Performance Materials, Inc.) was added, and stirred at 50 ° C for 4 hours. Thereafter, the mixed dispersion was dried at 80 ° C. to obtain an organic silicon compound-coated zirconia fine particle.

Comparative Example 3
In 2700 g of ethanol, 300 g of commercially available zirconia fine particles of a commercial product synthesized by a wet method having an average particle diameter of 15 nm and a specific surface area of 90 m ² / g were uniformly dispersed. While stirring this ethanol dispersion, 66.9 g of 3-methacryloxypropyltrimethoxysilane ("A-174" manufactured by Momentive Performance Materials, Inc.) was added, and the mixture was stirred at 50 ° C for 4 hours. Thereafter, the mixed dispersion was dried under reduced pressure at 60 ° C. to obtain zirconia fine particles coated with an organosilicon compound.

The following characteristic evaluations (3) to (5) were performed on the coated inorganic fine particles obtained in the above Examples 1 to 10 and Comparative Examples 1 to 3, and the results are shown in Table 1.
<Evaluation method>
(1) Measurement of average particle diameter, particle shape and uniformity evaluation Using a transmission electron microscope (H-7600) manufactured by Hitachi High-Technologies Corp., an image of particles is acquired at a magnification of 30,000 to 200,000, 200 or more The major diameter of the particles was measured, and the average particle diameter was measured by determining the average value. The particle shape was evaluated by observation of a TEM image, and the uniformity was evaluated by the relative standard deviation of the measured values of the average particle size.

(2) Measurement of specific surface area Using coated inorganic fine particles deaerated at 150 ° C., BET method based on adsorption and desorption of nitrogen gas using a fully automatic BET specific surface area measurement device (Macsorb HM Model-1210) manufactured by Mountech Co., Ltd. The specific surface area was measured by

(3) Measurement of Volatile Organic Compound Amount The evaluation of the volatile organic compound amount is described in O.3. S. P. Inc. The volume concentration of volatile organic compounds released into a measuring instrument with a volume of 140 mL when 0.500 g of coated inorganic fine particles is heated at 120 ° C. for 10 minutes using a volatile organic compound measuring device (VOC-401P) manufactured by Co. (Toluene conversion ppm) was measured. All volatile organic compounds that volatilized at the heating temperature were measured, including the main VOC species indicated by the Ministry of the Environment.

(4) Measurement of Coating Layer Amount in Coated Inorganic Fine Particles The amount of each element in the coated inorganic fine particles was quantified using a fluorescent X-ray analyzer (S8 TIGER) manufactured by Bruker AXS. From the obtained quantitative value, the weight fraction X of the coating layer to the coated inorganic fine particles was calculated based on the following formula 1.

In the formula (1), W _C is the amount of coating added, W _P is the amount of inorganic fine particles, M _C is the molecular weight of the coating, and M _{C '} is the molecular weight of the structure after the coating has reacted. p represents the reaction rate of the coating agent represented by the following formula 2.)

((Equation _{2), C "XRF} is a quantitative value of XRF for Si or Ti or Al element contained in the coating _{agent, P XRF} quantitative value in XRF metal or metal oxide constituting the inorganic fine particles as a raw material Where W _C represents the amount of coating added, W _P represents the amount of inorganic fine particles, M _C represents the molecular weight of the coating, and M _{C ′ ′} represents the atomic weight of Si or Ti or Al contained in the coating.

(5) Measurement of the refractive index of the transparent nanocomposite material and the coated inorganic fine particles After pouring the transparent nanocomposite material containing the coated inorganic fine particles into a PTFE mold having a volume of 15 mm × 30 mm × 0.5 mm, Sen Special Light Source Co., Ltd. The test piece hardened using the manufactured high pressure mercury lamp (handy cure 100) was produced. The refractive index of the transparent nanocomposite material was evaluated by measuring the refractive index of this test piece at a temperature of 25 ° C. and a wavelength of 589 nm using an Atago multi-wavelength Abbe refractometer (DR-M4). Furthermore, the refractive index of the coated inorganic fine particles was calculated from the refractive index of the obtained transparent nanocomposite material and the refractive index of the test piece made of ethoxylated-o-phenylphenol acrylate alone.

According to the results of Examples 1 to 10, according to the present invention, the surface of the inorganic fine particles synthesized by the hydrothermal reaction under high temperature and high pressure conditions is coated with a coating agent in a water solvent to obtain a coating of 100 ppm or less of volatile organic compounds. It was possible to obtain inorganic fine particles.
The coated inorganic fine particles of Comparative Examples 1 and 3 are manufactured by a method of dispersing inorganic fine particles in an organic solvent to perform surface coating, and then removing the organic solvent, and therefore contain a volatile organic compound derived from a dispersion medium. It became coated inorganic fine particles. The coated inorganic fine particles of Comparative Example 2 are coated inorganic fine particles coated on the surface in an aqueous solvent, but use is made of commercially available zirconia fine particles synthesized by a wet method. The low reactivity of the coating agent resulted in 100 ppm or more of the coated inorganic fine particles of volatile organic compounds.

[Preparation of transparent nanocomposite materials]
Example 11
100 g of ethoxylated-o-phenylphenol acrylate ("NK ester A-LEN-10" manufactured by Shin-Nakamura Chemical Co., Ltd.) to 100 g of the coated inorganic fine particles described in Example 1 above, 1-hydroxycyclohexyl phenyl ketone (manufactured by BASF Corporation) 6 g of IRGACURE 184 ") was added and dispersed for 1 hour at 16,000 rpm using a high-speed stirrer to obtain a nanocomposite material containing 50% by weight of coated zirconia fine particles. A transparent nanocomposite material containing coated inorganic fine particles is coated with a film thickness of 40 μm on a PET film (“Lumirror T60” manufactured by Toray Industries, 12 mm × 80 mm × 100 μm), then a high pressure mercury lamp (Handy Cure 100 manufactured by Sen Special Light Source Co. The test piece cured using was made. It was 83.4% T when the transmittance | permeability in wavelength 400nm of this test piece was measured using the reference as a PET film and using the ratio beam-type ultraviolet visible spectrophotometer (U-5100) made from Hitachi High-tech Science as a reference. . Moreover, after pouring the obtained nanocomposite material in a PTFE mold having a volume of 15 mm × 30 mm × 0.5 mm, a test piece cured using a high pressure mercury lamp (Handy Cure 100) manufactured by Sen Special Light Source Co., Ltd. Made. The refractive index of this test piece at a temperature of 25 ° C. and a wavelength of 589 nm was measured using an Atago Co. multi-wavelength Abbe refractometer (DR-M4) and found to be 1.649.

Comparative Example 4
100 g of ethoxylated-o-phenylphenol acrylate ("NK ester A-LEN-10" manufactured by Shin-Nakamura Chemical Co., Ltd.) to 100 g of the coated inorganic fine particles described in Comparative Example 1 described above; 6 g of IRGACURE 184 ") was added and dispersed for 1 hour at 16,000 rpm using a high-speed stirrer to obtain a nanocomposite material containing 50% by weight of coated zirconia fine particles. When the obtained nanocomposite was evaluated for transparency and refractive index in the same manner as in Example 11, the transmittance at a wavelength of 400 nm was 29.3% T, and the refractive index was 1.652.

From the results of Example 11, the coated inorganic fine particles of the present invention have good dispersibility in an organic compound, so it is possible to obtain a non-solvent-based, highly transparent nanocomposite material.
The nanocomposite material of Comparative Example 4 uses coated inorganic fine particles using commercially available zirconia fine particles synthesized by a wet method, but the dispersibility in organic compounds is low due to the difference in the method of producing the inorganic fine particles, It becomes a nanocomposite material with low transparency.

The coated inorganic fine particles of the present invention can be suitably used for transparent nanocomposite materials used for liquid crystal displays, organic ELs, LEDs, optical members such as lenses, electronic members, coating materials, dental materials and the like.

Claims

Any of the following formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2) on the surface of the inorganic fine particles A coated inorganic fine particle having a coated layer, which is obtained by reacting at least one of a compound represented by the formula: and a salt thereof,
The average particle diameter of the inorganic fine particles is less than 100nm or 1 nm, and a specific surface area of less than 1 m 2 / g or more 3,000 m 2 / g,
Coated inorganic fine particles characterized in that the content of volatile organic compounds is less than 100 ppm.

(In the formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2), R 1 is each independently R 2 is a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, R 2 is a j-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, or the number of silicon atoms And R 5 and R 4 each independently represent a structure represented by any one of the following formulas (bc-1) to (bc-6), and R 5 is a j-valent (poly) siloxy group of 1 to 20. R 6 is a hydrocarbon group having 4 to 30 carbon atoms which may contain a hetero atom, R 6 is an n-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, and X 1 is respectively independently an alkoxy group having 1 to 10 carbon atoms, a hydrogen atom, a chlorine atom, a bromine atom, or iodine atom, X 2 and X 3 are each independently Is an alkoxy group having 1 to 10 carbon atoms, an acyloxy group having 1 to 10 carbon atoms which may contain a hetero atom, a chlorine atom, a bromine atom or an iodine atom, and h is an integer of 1 to 4, i Are each independently an integer of 1 to 3, j is an integer of 2 to 10, k is an integer of 1 to 4, l is an integer of 1 to 3, m is an integer of 1 to 3, n is It represents an integer of 2-10. However, an alkoxy group and / or acyloxy groups X 2 and X 3, in combination with other alkoxy groups and / or acyloxy groups X 2 and X 3 form a cyclic structure, respectively May be

(In the formulas (bc-1) to (bc-6), R 7 each independently represents a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom, and R 8 includes a hetero atom R 9 may independently be a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms which may contain a hetero atom, or a hetero atom. Represents a hydrocarbon group having 1 to 20 carbon atoms, or a hydrogen atom.)
The coated inorganic fine particles according to claim 1, wherein the content of the volatile organic compound is 1 ppm or more and less than 80 ppm.
The coated inorganic fine particles according to claim 1 or 2, wherein the refractive index is 1.5 or more.
The coated inorganic fine particles according to any one of claims 1 to 3, wherein the inorganic fine particles are at least one selected from the group consisting of metal oxides having a refractive index of 1.5 or more.
The coated inorganic fine particles according to any one of claims 1 to 4, wherein the inorganic fine particles are at least one selected from the group consisting of zirconium dioxide (ZrO 2 ) and titanium dioxide (TiO 2 ).
The coating layer is a layer formed by reacting at least one selected from the group consisting of a compound represented by the formula (A-1) and a compound represented by the formula (A-2) The coated inorganic fine particle according to any one of claims 1 to 5.
Compounds represented by any one of the above formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2) The coated inorganic fine particles according to any one of claims 1 to 6, wherein 3 parts by weight or more and 100 parts by weight or less of the inorganic fine particles are added and reacted.
The coated inorganic fine particles according to any one of claims 1 to 7, wherein a content of the coating layer is 1% by weight or more and 45% by weight or less.
(1) a preparation step of preparing an aqueous solution in which the metal hydroxide and / or a condensate of the metal hydroxide dissolves and / or disperses, (2) the aqueous solution prepared in the preparation step has a temperature of 200 ° C. or more and a pressure of 20 MPa As described above, a hydrothermal reaction step of producing an inorganic fine particle by causing a hydrothermal reaction in a reaction time of 0.1 minutes or more, (3) an isolation step of isolating the inorganic fine particle generated in the hydrothermal reaction step, (4) The inorganic fine particles isolated in the isolation step and the following formula (A-1), (A-2), (B-1), (B-2), (C), (C), (D-1), and A method for producing coated inorganic fine particles, comprising: a coating step of reacting at least one of the compounds represented by any of D-2) in an aqueous solvent.

(In the formulas (A-1), (A-2), (B-1), (B-2), (C), (D-1), and (D-2), R 1 is each independently R 2 is a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, R 2 is a j-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, or the number of silicon atoms And R 5 and R 4 each independently represent a structure represented by any one of the following formulas (bc-1) to (bc-6), and R 5 is a j-valent (poly) siloxy group of 1 to 20. R 6 is a hydrocarbon group having 4 to 30 carbon atoms which may contain a hetero atom, R 6 is an n-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom, and X 1 is respectively independently an alkoxy group having 1 to 10 carbon atoms, a hydrogen atom, a chlorine atom, a bromine atom, or iodine atom, X 2 and X 3 are each independently Is an alkoxy group having 1 to 10 carbon atoms, an acyloxy group having 1 to 10 carbon atoms which may contain a hetero atom, a chlorine atom, a bromine atom or an iodine atom, and h is an integer of 1 to 4, i Are each independently an integer of 1 to 3, j is an integer of 2 to 10, k is an integer of 1 to 4, l is an integer of 1 to 3, m is an integer of 1 to 3, n is It represents an integer of 2-10. However, an alkoxy group and / or acyloxy groups X 2 and X 3, in combination with other alkoxy groups and / or acyloxy groups X 2 and X 3 form a cyclic structure, respectively May be

(In the formulas (bc-1) to (bc-6), R 7 each independently represents a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom, and R 8 includes a hetero atom R 9 may independently be a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms which may contain a hetero atom, or a hetero atom. Represents a hydrocarbon group having 1 to 20 carbon atoms, or a hydrogen atom.)
A nanocomposite material comprising the coated inorganic fine particles according to any one of claims 1 to 8 dispersed in a transparent organic compound.
The organic compound is a polymerizable monomer and / or oligomer, and the spectral transmittance of light having a wavelength of 400 nm of the polymer when the monomer and / or oligomer is polymerized is 65% or more. Nanocomposite materials as described.
The organic compound is at least one selected from the group consisting of a thermoplastic resin, a thermosetting resin, an ultraviolet curable resin, and an electron beam curable resin, and the spectral transmittance of light having a wavelength of 400 nm is 65% or more The nanocomposite material according to claim 10, which is
The nanocomposite material according to any one of claims 10 to 12, wherein the content of the coated inorganic fine particles is 10% by weight or more and 85% by weight or less.