WO2008010533A1 - Metal oxide nanoparticle and method for producing the same - Google Patents

Abstract

Disclosed is a metal oxide nanoparticle exhibiting high dispersibility in various solvents, monomers or polymers, which is capable of imparting a resin composition or the like with various characteristics. Specifically disclosed is a metal oxide nanoparticle coated with two or more coating agents, which is characterized in that at least one of the coating agents is represented by the following formula (I). R1-COOH (I) (In the formula, R1 represents a hydrocarbon group having 6 or more carbon atoms.)

Description

 Specification

 Metal oxide nanoparticles and production method thereof

 Technical field

 [0001] The present invention relates to a metal oxide nanoparticle, a method for producing the nanoparticle, and a composition containing the nanoparticle.

 Background art

 [0002] In recent years, nanoparticles of metal oxides have contributed to the enhancement of functionality and performance of various materials such as optical materials, electronic component materials, magnetic recording materials, catalyst materials, and ultraviolet absorbing materials. It has attracted a lot of attention. For example, Japanese Patent Application Laid-Open No. 2003-73563 describes a technique for improving the refractive index by dispersing zirconium oxide nanoparticles in a thermoplastic resin since acid zirconium particles exhibit a high refractive index. ing. JP-A-2005-162902 discloses a technique for adding a metal oxide to a cyclic olefin-based graft copolymer having a specific structure in order to improve solvent resistance and dimensional stability. Has been

[0003] Breaking-down processes and building-up processes are known as methods for producing metal oxide particles. A mechanical pulverization method is generally used as the breaking-down process, but it is difficult to efficiently produce fine particles with a particle size of L m or less, and impurities may be mixed during pulverization. Is expensive. In contrast, the Building-up process is a method of preparing particles by chemical reaction in the gas phase or liquid phase. Fine particles can be prepared by controlling reaction conditions and selecting raw materials.

 [0004] Of the building-up processes, the gas phase method requires special equipment and reaction conditions, and there are many problems in terms of safety and cost.

[0005] Examples of the liquid phase method include a coprecipitation method, an alkoxide method, and a hydrothermal synthesis method. However, the coprecipitation method has a problem that the metal oxide nanoparticles generated in the heating process grow. There is. For example, the alkoxide method described in JP-A-6-287005 is a method of obtaining metal oxide particles by hydrolyzing a metal alkoxide, but this method converts some metal oxides. In addition, the raw materials are expensive and the resulting metal acid The crystallinity of the compound is insufficient. The hydrothermal synthesis method described in Japanese Patent Application Laid-Open No. 2005-255450 is to react a metal oxide precursor at a high temperature and high pressure, but at 30 ° C. at 400 ° C. Therefore, there is a problem that particles are coarsened and a large amount of nanoparticles cannot be produced at low cost.

 [0006] In addition to the problem that the metal oxide nanoparticles are difficult to produce as described above, there is a problem that the dispersibility in a solvent is low. That is, the metal oxide nanoparticles have good dispersibility in an aqueous solvent, and the dispersibility in a low polarity organic solvent, monomer, polymer, etc. is low. For example, in the example of JP-A-2005-162902, an example in which metal oxide particles are dispersed in a polymer is the same as that of the copolymer in a graft copolymer having a polysiloxane structure. It is only a film in which colloidal silica, which has a chemical structure and is considered to have high affinity, is dispersed.

 [0007] Therefore, dispersibility in various solvents is improved by surface-treating metal oxide particles. However, since the dispersibility of the metal oxide particles before the surface treatment is low and agglomeration is fused, the dispersibility cannot be improved as a result because it is difficult to effectively treat the surface itself. Therefore, in order to disperse the metal oxide particles during the surface treatment, a high-temperature and high-pressure treatment is performed (JP 2005-193237), a mill treatment (JP 2005-220264), We had to do costly and labor-intensive processing

[0008] Therefore, the applicant's researchers have developed a method for producing metal oxide particles containing carboxylic acid residues by heating an alcohol solution such as zinc acetate in the presence of a small amount of water. (Japanese Patent Laid-Open No. 2000-185916). The metal oxide obtained by this method has improved dispersibility in a resin solution or the like.

 [0009] In addition, an organic phase Zr (IV) -oxidized surface-treated with a tertiary carboxylic acid by hydrothermally treating a heterogeneous solution of a tertiary carboxylic acid solution and water at around 200 ° C. A method of producing zirconium nanoparticles is disclosed in Yasuhiro Konishi et al., Chemical Society of Japan 65th Annual Conference, Abstracts, N202 (2000).

Disclosure of the invention [0010] As described above, conventionally, techniques for improving the dispersibility of metal oxide particles have been studied. In particular, in recent years, it has been demanded to further improve the dispersibility in various solvents and the like that apply the excellent characteristics of zirconium oxide particles. For example, zirconium oxide nanoparticles surface-treated with tertiary carboxylic acid are disclosed in Yasuhiro Konishi et al., Proceedings of the 65th Annual Meeting of the Chemical Society of Japan, N202 (2000). However, according to the findings by the present inventors, the particles exhibit dispersibility in toluene with low polarity, but have low dispersibility in organic solvents and monomers with relatively high polarity. Therefore, for example, a composition having excellent characteristics such as a high refractive index and high toughness cannot be produced by conducting a polymerization reaction after dispersing the particles in a monomer. In addition, as disclosed in Japanese Patent Application Laid-Open No. 2000-185916, the applicant's researchers have developed a technique for improving dispersibility by bonding carboxylic acid residues to metal oxide particles! In recent years, however, the level of dispersibility is extremely high, and it has been impossible to satisfy the demand.

[0011] Thus, the problem to be solved by the present invention is that the metal oxide nanoparticle has high dispersibility in various solvents, monomers or polymers and can impart properties such as a high refractive index to the resin composition. To provide particles. Another object of the present invention is to provide a method for producing the particles, a composition containing the particles, and the like.

 [0012] The inventors of the present invention have intensively studied to solve the above problems. As a result, the present inventors have found that a coating agent for coating the surface of the metal oxide nanoparticles is extremely important for improving the dispersibility of the metal oxide nanoparticles.

 [0013] For example, in the method for producing particles described in Japanese Patent Application Laid-Open No. 2000-185916 developed by a researcher of the present applicant, a relatively long chain carboxylic acid is also used. Only short-chain carboxylic acid residues such as acetoxy group were bonded to the surface. Therefore, the dispersibility of the particles has not been able to sufficiently satisfy recent requirements. Moreover, in the technique described in Yasuhiro Konishi et al., Zirconium oxide particles are coated with one kind of relatively long chain carboxylic acid, but the effect of improving the dispersibility is not always satisfactory. .

[0014] Therefore, the present inventors first coated the particles with a relatively long-chain carboxylic acid, and then treated the particles with another coating agent and coated them with two or more coating agents to cope with various solvents. The present invention has been completed by finding that the dispersibility is improved and the utilization efficiency of metal oxide nanoparticles is increased.

 [0015] The metal oxide nanoparticles of the present invention are coated with two or more coating agents; at least one of the coating agents is represented by the following formula (I): Features.

R ¹ -COOH (1)

[Wherein R ¹ represents a hydrocarbon group having 6 or more carbon atoms. ]

 [0016] The method for producing metal oxide nanoparticles according to the present invention comprises preparing a coating agent (I) metal composite from at least a metal oxide precursor and a coating agent represented by the following formula (I): The step of:

R ¹ -COOH (1)

[Wherein R ¹ represents a hydrocarbon group having 6 or more carbon atoms. ]

 [0017] A step of obtaining metal oxide nanoparticles coated with the coating agent (I) by mixing water with the coating agent (I) metal composite and performing a hydrothermal reaction below IMPaG; and A step of coating the metal oxide nanoparticles with two or more coating agents by allowing a coating agent other than the coating agent (I) to act on the obtained metal oxide nanoparticles. .

 [0018] The metal oxide nanoparticle composition of the present invention is characterized by containing the metal oxide nanoparticle. Since the metal oxide nanoparticles of the present invention are extremely dispersible, the metal oxide nanoparticles are uniformly dispersed in the composition. As a powerful composition, the metal oxide nanoparticles are dispersed in one or more selected from the group consisting of a solvent, a monomer, a polymer, and a plasticizer, and the metal oxide nanoparticles are And a coating composition, a resin composition, a film, an optical material, and an optical semiconductor encapsulant containing the metal oxide nanoparticles.

 BEST MODE FOR CARRYING OUT THE INVENTION

 [0019] The metal oxide constituting the particles of the present invention is not particularly limited as long as various properties can be given by adding to the material. Examples of the metal oxide include Al, Ti, V, Ni, Cu, Zn, Y, Zr, Nb, Mo, In, Sn, Sb, Hf, La, Ce, Nd, and Sm force. One kind or two or more kinds of acids selected from the above can be selected.

[0020] The metal oxide constituting the particles of the present invention preferably has higher crystallinity. A crystalline material is more stable and generally more active than an amorphous material. Also, acid When zirconium or the like is used as an optical material or the like, the one having higher crystallinity has a higher utility value.

 [0021] The crystallinity of the metal oxide constituting the particles of the present invention can be evaluated by the c value calculated by the following formula (1) using the result of X-ray crystal diffraction.

 C = 100 X (s 1 -s 2) / S 1 (1)

 [In the formula, S represents the total area value of the X-ray diffraction chart obtained by X-ray diffraction measurement,

 1

 S represents the area value of the base portion of the X-ray diffraction chart obtained by X-ray diffraction measurement. ]

2

 [0022] Since the crystallinity of the metal oxide is not changed by the coating agent, X-ray diffraction can be measured by coating only with the coating agent (I). It may be measured in the coated state. The measurement range of X-ray diffraction is not particularly limited, but it is preferable that the maximum diffraction peak of each crystal structure of the metal oxide to be measured is included. For example, in the case of acid zirconium, the maximum diffraction peaks of tetragonal, cubic and monoclinic crystal structures are detected in the range of 20:26 to 38 °. It is preferable to measure at least this range. In addition, the values of S and S can be calculated from the X-ray diffraction chart obtained from the XRayCryst

 1 2

 Obtained from analysis software such as al.

 [0023] The higher the crystallinity of the metal oxide composing the particles of the present invention, the better. Therefore, the C value is preferably 15 or more, more preferably 20 or more, and even more preferably 30 or more.

 [0024] There are three known crystal forms of zirconium oxide, cubic, tetragonal and monoclinic. As the zirconium oxide of the present invention, those having a high refractive index are preferred, so those having tetragonal crystals of 70% or more of the entire crystal structure are preferred, and those having 75% or more are more preferred 85% The above is more preferable. The ratio of tetragonal crystals can be obtained by identifying the diffraction peaks attributed to tetragonal, cubic and monoclinic crystals from the X-ray diffraction chart and calculating the content ratio with analysis software such as XRayCrystal. it can. The tetragonal crystal of zirconium oxide is confirmed by the presence of diffraction peaks on the lattice planes (101), (112), (200), (211), and (110) in the X-ray structural diffraction analysis data. Togashi.

[0025] The metal oxide nanoparticles of the present invention are coated with two or more coating agents, at least one of which is a coating agent represented by the formula (I). R ¹ -COOH (1)

[Wherein R ¹ represents a hydrocarbon group having 6 or more carbon atoms. ]

[0026] The surface of the metal oxide nanoparticles is generally hydrophilic and positively charged. Therefore, the carboxyl group in the formula (I) has an affinity for the metal oxide nanoparticles, and can coat the nanoparticles. In addition, the carboxyl group in the coating agent of the formula (I) may be bonded to the nanoparticles in the form of COO.

 [0027] The hydrocarbon group having 6 or more carbon atoms particularly has an action of enhancing the dispersibility of the metal oxide nanoparticles in a nonpolar solvent or the like. More specifically, the metal oxide nanoparticles of the present invention can be dispersed in a nonpolar solvent such as toluene, xylene or cyclohexane.

 [0028] The coating agent of the formula (I) includes straight-chain carboxylic acids such as hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid and stearic acid; Branched carboxylic acids such as sanic acid, 2-methylheptanoic acid, 4-methylotasanic acid, and neodecanoic acid; cyclic carboxylic acids such as naphthenic acid and cyclohexanedicarboxylic acid can be used. Of these, branched chain carboxylic acids such as neodecanoic acid and 2-ethylhexanoic acid are preferred. The reason for this is not always clear, but the hydrophobic coating agent having a branched hydrocarbon chain rather than the straight hydrocarbon chain further enhances the effect of dispersing particles in a hydrophobic organic solvent or the like. be able to.

[0029] Only one type of coating agent of the formula (I) may be used, or a mixture of two or more types may be used.

[0030] The metal oxide nanoparticles of the present invention are coated with another coating agent in addition to the coating agent of formula (I). As a result, it exhibits excellent dispersibility in various solvents. Examples of other coating agents include coating agents that increase the dispersibility of nanoparticles in polar solvents, coating agents that increase dispersibility in monomers and polymers, and coating agents that further increase dispersibility in nonpolar solvents. .

[0031] The coating agent that enhances the dispersibility of the nanoparticles in the polar solvent can be bonded to the surface of the hydrophilic metal oxide nanoparticles and has a hydrophilic group, so that the particles for solvents and monomers having a relatively high polarity are used. The dispersibility of can be improved. For example, selected from the group consisting of hydroxyl group, amino group, thiol group, carboxyl group, epoxy group, and alkoxy group. Examples thereof include a coating agent having a plurality of at least one selected functional group. Of course, it may have other functional groups in addition to these functional groups.

Possible coatings include aluminum alkoxides such as aluminum trimethoxide, aluminum triethoxide, aluminum-umtriisopropoxide, aluminum tree n-butoxide, aluminum tree sec-butoxide, aluminum tri-t-butoxide; diisopropoxide Aluminum ethyl acetate acetate, diisopropoxy aluminum alkyl acetate acetate, diisopropoxy aluminum monometatalylate, aluminum stearate oxide trimer, isopropoxy aluminum alkyl acetate acetate mono (dioctyl phosphate), etc. Aluminum coupling agent; titanium n-butoxide, titanium tetra-butoxide, titanium tetra- _sec butoxide, titanium tetra Titanium alkoxides such as ethoxide, titanium tetraisobutoxide, titanium tetramethoxide, titanium tetra (methoxypropoxide), titanium tetra (methoxyphenoxide); isopropyl triisostearoyl titanate, isopropyl trioctanoyl titanate, Tetraoctylbis (ditridecylphosphite) titanate, tetraisopropylpropyl (dioctylphosphate) titanate, isopropyltris (dioctylpyrophosphate) titanate, bis (dioctylpyrophosphate) oxyacetate titanate , Titanium coupling agents such as bis (dioctylpyrophosphate) ethylene titanate; vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloxyp Zirconium coupling agents such as Ropitritoroxysilane, 3-Ataryloxypropyltrimethoxysilane, N— (2 Aminoethyl) -3 —Aminopropylmethyldimethoxysilane, N— (2 Aminoethyl) 3 Aminopropyl Trimethoxysilane; Zirconium tetra n —Butoxide, Zirconium tetra-t-Butoxide, Zirconium tetra (2-Ethylhexoxide), Zirconium tetraisobutoxide, Zirconium tetraethoxide, Zirconium tetraisopropoxide, Zirconium tetra n-propoxide, Zirconium tetra (2— Zirconium alkoxides such as methyl-2-butoxide; zirconium di-n-butoxide (bis 2,4-pentanedionate), zirconium tri-n-butoxide pentadionate, dinoleconium Zirconium compounds such as di-meta Tari rate dibutoxide; hydroxystearic acid, hydroxycarboxylic acids such as salicylic acid; 2- [2- (2-methoxyethoxy) ethoxy] E, such as acetic acid A carboxylic acid coupling agent such as carboxylated polybutadiene and carboxylated polyisoprene; a carboxylic acid polymer such as maleic acid-modified polypropylene; For example, the silane coupling agent becomes a polymer having a siloxane structure and coats the particles, and can improve the dispersibility of the particles in a polar solvent. Therefore, the polymers of the above examples are also included in the coating agent of the present invention. And. In addition, the silane coupling agent is particularly convenient because a side chain can introduce a substituent having high affinity for a monomer or the like. Preferably, a silane coupling agent, hydroxycarboxylic acid, or ether carboxylic acid is used.

 [0033] Only one type of coating agent that enhances dispersibility in a polar solvent may be used, or a mixture of two or more types may be used.

 [0034] The coating agent that enhances the dispersibility of the nanoparticles to the monomer or polymer has a group that exhibits affinity for the metal oxide as well as a group that exhibits affinity for the metal oxide. The dispersibility of the particles can be improved. For example, if particles are coated with a coating agent having a vinyl group, such as (meth) acrylic acid or (meth) acrylic acid ester, particles for monomers such as (meth) acrylic acid or (meth) acrylic acid ester having the same bull group The dispersibility of can be improved. In addition, if the particles are coated with a coating agent having a phenyl group, dispersion of the particles with respect to the monomer or polymer having a phenyl group, such as a monomer such as styrene, or a polymer such as styrene resin or phenol resin. Can be improved.

[0035] As a powerful coating agent, aluminum-based coupling agents such as diisopropoxyaluminum monometatalylate; butyltrimethoxysilane, butyltriethoxysilane, 3-methacryloxypropyltriethoxysilane, 3 Examples thereof include silane coupling agents such as atalyloxypropyltrimethoxysilane, p-styryltrimethoxysilane, and phenyltrimethoxysilane.

 [0036] When the coating agent represented by the formula (I) has a branched hydrocarbon group having 6 or more carbon atoms, the at least one coating agent other than the coating agent (I) is represented by the formula The coating agent represented by (ii) can be mentioned.

R ² — COOH · · · (II) [Wherein R ² represents a linear hydrocarbon group having 6 or more carbon atoms. ]

 [0037] The coating agent (I) having a branched chain hydrocarbon group having 6 or more carbon atoms can improve dispersibility in a nonpolar solvent or the like, but is also used in combination with the coating agent of the formula (Π) By doing so, the dispersibility can be further improved. Examples of the coating agent of the formula (ii) include straight chain carboxylic acids such as hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid and stearic acid.

 [0038] Although the coating agent for coating the particles of the present invention may be a total of two types, such as the coating agent of formula (I) and other coating agents, it increases dispersibility in the coating agent of formula (I) and the polar solvent. A total of three or more types of coating agents, such as a coating agent that improves dispersibility in monomers and polymers, may be used. Also, for example, use two or more coatings of formula (I).

 [0039] As described above, the nanoparticles of the present invention are coated with another coating agent in order to enhance the dispersibility in a desired solvent and the like together with the coating agent (I). The ratio of these coating agents may be appropriately adjusted in order to improve the dispersibility in the solvent, monomer, and polymer as the dispersion medium. In general, the molar ratio of the other coating to the coating (I) when two types of coating are used is preferably 0.1 or more and 30 or less, for example 0.2 or more and 25 or less. More preferably 0.3 or more and 15 or less. When the molar ratio is within this range, the effect of improving the dispersibility in a solvent or the like according to both coating agents is suitably exhibited. The ratio of the coating agent bonded to the surface of the particle can be determined from, for example, an NMR vector, an analysis result using a CHN coder, an element analyzer, or an X-ray fluorescence analyzer.

 [0040] The particle diameter of the metal oxide nanoparticles of the present invention is not particularly limited as long as it can be said to be at the nano level, but is usually 20 nm or less. If it exceeds 20 nm, for example, when it is a dispersion, the transparency may be lowered, which is not preferable. More preferably, it is 1 nm or more and 19 nm or less, and further preferably 2 nm or more and 18 nm or less.

[0041] A general method can be used as a method of measuring the particle diameter. For example, magnify the particles with a transmission electron microscope (TEM), field emission transmission electron microscope (FE—TEM), field emission scanning electron microscope (FE—SEM), and select 100 particles at random. Then, the length in the major axis direction is measured, and the average value is taken as the particle diameter. Particle shape is a sphere Shapes, elliptical spheres, cubes, cuboids, pyramids, needles, columns, rods, cylinders, flakes, plates, flakes, etc. The direction length shall be measured. The shape of the particles of the present invention is preferably spherical, granular, or columnar in consideration of dispersibility in a solvent.

 [0042] The particle size distribution of the metal oxide nanoparticles according to the present invention is σ Ζχ Χ ΙΟΟ, where σ is the standard deviation of the particle size distribution of the particles, and X is the 50% cumulative diameter (nm) of the particles ] The conversion coefficient expressed by] is preferably 30% or less. If the conversion coefficient exceeds 30%, the particle size varies, and as a result, the physical properties such as light transmittance and refractive index may vary. The conversion factor is preferably 25% or less, more preferably 20% or less.

 [0043] The ratio of the coating agent to the metal oxide in the metal oxide nanoparticles of the present invention is preferably 40% by mass or less in terms of weight loss when the organic component is removed by heating in an air atmosphere. If the weight loss rate exceeds 40% by mass, the amount of the coating agent is too large, and the original action and effect of the metal oxide may not be sufficiently exhibited. On the other hand, if the weight loss rate is less than 5% by mass, the amount of the coating agent may be too small and the dispersibility of the particles may not be sufficiently improved. Therefore, the weight loss rate is preferably 5% by mass or more. More preferably, it is 10 mass% or more and 30 mass% or less.

 [0044] The weight loss rate is calculated by, for example, using a TG-DTA analyzer manufactured by Mac Science Co., Ltd., heating the particles to 800 ° C at a rate of 10 ° CZ in an air atmosphere, and reducing the mass Z before heating X Calculated by 100. In addition, from the viewpoint of thermal stability, the particles of the present invention preferably have an exothermic peak of 150 ° C or higher when measured with a TG-DTA analyzer, more preferably 190 ° C or higher. .

[0045] Since the metal oxide nanoparticles of the present invention are coated with two or more kinds of coating agents, they are highly dispersible in various solvents. The dispersibility in a solvent or the like can be adjusted by the ratio of these coating agents. For example, when coating nanoparticles with a coating agent (I) that increases dispersibility in nonpolar solvents and a coating agent that increases dispersibility in polar solvents, the coating agent (I If the amount of the other coating agent is increased in order to increase the amount of the other coating agent in order to increase the dispersibility in polar high V, solvent, etc., it may be adjusted accordingly. [0046] The method for producing metal oxide nanoparticles according to the present invention comprises a step of preparing a coating agent (I) metal composite from at least a metal oxide precursor and a coating agent of formula (I); Coating (I) A step of obtaining metal oxide nanoparticles coated with coating (I) by mixing water with the metal complex and hydrothermally reacting at less than IMPaG; and the obtained metal acid A step of coating metal oxide nanoparticles with two or more coating agents by causing a coating agent other than the coating agent (I) to act on the metal nanoparticles. Hereinafter, the method will be described in the order of execution.

 [0047] In the method of the present invention, first, at least a metal oxide precursor and a coating agent of the formula (I) are mixed to prepare a coating agent (I) metal composite.

 [0048] Conventionally, the technology for producing metal oxide particles by hydrothermal reaction has been known, but because it used only an aqueous solution of a metal salt, it was 30 MPa at 400 ° C! Conditions were necessary. On the other hand, in the present invention, since the coating agent (I) metal composite prepared in advance is subjected to a hydrothermal reaction, fine particles can be produced under a relatively mild condition of less than IMPaG. The form of the metal in the coating agent (I) metal composite is not necessarily clear, but it may be a metal ion, for example, and may form a salt with the coating agent (I) having a carboxy group.

 [0049] The metal oxide precursor that is a raw material of the method of the present invention can form a coating agent (I) metal complex together with the coating agent (I), and can also form a coating agent (I) by hydrothermal reaction. ) Metal composite force There is no particular limitation as long as it is a precursor that becomes metal oxide nanoparticles. For example, metal hydroxide, chloride, oxychloride, oxynitrate, sulfide, carboxylate, amino compound salt, metal alkoxide, and the like can be used. Of these, oxysalts and oxynitrates are preferred because they are inexpensive and provide fine particles.

[0050] An organic solvent may be further added to the coating agent (I) metal composite formed from the metal oxide precursor and the coating agent of the formula (I). The metal oxide precursor and the coating agent (I) alone may form a viscous complex, and the hydrothermal reaction in the next step may not proceed efficiently. By dissolving, the hydrothermal reaction can proceed efficiently. Any organic solvent may be used as long as it has good solubility in the coating agent (I) metal composite. Also, when water is collected in the next process, it forms water and two phases. It is also possible to carry out the hydrothermal reaction while maintaining two phases. As the strong organic solvent, for example, hydrocarbons, ketones, esters, ethers, alcohols, amines, carboxylic acids and the like can be generally used. Considering the hydrothermal reaction in the next step, those having a boiling point of 20 ° C. or higher are suitable. In an organic solvent having a boiling point of less than 120 ° C, the vapor pressure during the hydrothermal reaction becomes high, and thus the reaction pressure has to be increased. As a result, there is a possibility that the particles are likely to be aggregated or fused. Therefore, an organic solvent having a boiling point S of 180 ° C or higher is more preferable, and an organic solvent having a boiling point of 210 ° C or higher is more preferable. More specifically, decane, dodecane, tetradecane, octanol, decanol, cyclohexanol, terbinol, ethylene glycol, diethylene glycol, 1,2 propanediol, 1,3 propanediol, 1,4 butanediol, 2,3 butanediol Hexanediol, otatanic acid, 2-ethylhexanoic acid, neodecanoic acid and the like can be used.

[0051] The amount of the coating agent (I) metal composite in the mixture of the coating agent (I) metal composite and the organic solvent can usually be about 2% by mass or more and 95% by mass or less. If it is less than 2% by mass, there may be a problem that the amount of metal oxide nanoparticles generated in one reaction is reduced, and if it exceeds 95% by mass, the coating agent in the reaction solution (I) Metal complex In some cases, the reaction may not proceed smoothly due to the concentration of the solution being too high. More preferably, it is about 5% by mass or more and 90% by mass or less.

 [0052] Coating Agent (I) The mixture of the metal composite and the organic solvent is preferably stirred while heating. The conditions are not particularly limited, but the mixture is heated and stirred until the metal oxide precursor is completely dissolved and a uniform coating agent (I) metal composite is formed. For example, stirring may be performed at about 30 to 80 ° C for about 30 minutes to about 5 hours.

 [0053] Next, water is mixed with the coating agent (I) metal composite and subjected to a hydrothermal reaction below IMPaG to obtain metal oxide nanoparticles coated with the coating agent (I).

 [0054] The type of water is not particularly limited, but preferably pure water is used. Further, since the pH of the water is preferably 4 or more and 9 or less, the pH may be adjusted by appropriately adding acid, alkali, or the like.

[0055] The amount of water is preferably such that (number of moles of water) Z (number of moles of metal) is 4 or more and 100 or less. When the ratio is less than 4, metal oxide nanoparticles with poor dispersibility are formed. There is a risk of doing so. On the other hand, if the ratio exceeds 100, the amount of water increases, which may cause a problem that the amount of metal oxide nanoparticles generated in one reaction decreases. The ratio is

8 or more and 50 or less are more preferable.

 [0056] Coating agent (I) —A dispersant may be further added to the mixed solution of the metal composite and water. Any dispersant can be used as long as it can exhibit dispersibility in either or both of the organic phase and the aqueous phase. Examples of powerful dispersants include carboxylic acids, amine compounds, alkoxides, silane coupling agents, titanate coupling agents, and aluminate coupling agents. A suitable amount of the dispersant used can be about 0.01 to 2 mole times or more with respect to the metal oxide precursor.

 [0057] Coating Agent (I) When the mixed solution of the metal complex and water is formed into two layers in a stationary state, it may be suspended by vigorous stirring immediately before the subsequent hydrothermal reaction.

 [0058] The two-layer reaction mixture is hydrothermally reacted at less than IMPaG. If the pressure is higher than IMPaG, the particles may be easily aggregated and the apparatus cost may be increased. On the other hand, if the reaction is performed at normal pressure, a high temperature is required for crystal formation and aggregation due to heat may be promoted. Therefore, the reaction is preferably performed at 0. IMPaG or more, more preferably 0.2 MPaG or more.

 [0059] The reaction temperature may be set so that the pressure in the reaction vessel is less than IMPaG in consideration of the boiling point of the solvent to be used. Considering the saturated water vapor pressure of water, it is preferable to react at a temperature of 180 ° C or lower.

 [0060] The reaction time is not particularly limited, but is usually from about 0.1 hour to about 10 hours, preferably from 0.5 hour to 6 hours.

 [0061] The reaction system atmosphere is not particularly limited, and may be air, oxygen, hydrogen, nitrogen, argon, carbon dioxide, or the like. Considering the suppression of aggregation and safety, it is preferable to react in an inert gas atmosphere such as nitrogen or argon.

[0062] As a result of the hydrothermal reaction, metal oxide nanoparticles coated with the coating agent (I) are generated and precipitated at the bottom of the reaction vessel. The metal oxide nanoparticles are preferably purified to remove particle aggregates and precipitated carbon. For example, the precipitated metal oxide nanoparticles are separated by filtration, and then the nanoparticles are dissolved in toluene and filtered to remove aggregated particles and carbon. Next, the filtrate obtained was concentrated under reduced pressure to remove toluene, etc. By doing so, the metal oxide nanoparticles can be purified.

 [0063] The organic solvent used for producing the metal oxide nanoparticles can be separated from the aqueous phase and reused. Powerful reuse is preferable because it reduces the amount of waste liquid and manufacturing costs.

 [0064] Next, a coating agent other than the coating agent (I) is allowed to act on the obtained metal oxide nanoparticles to coat the surface of the nanoparticles with two or more coating agents.

 [0065] First, the obtained metal oxide nanoparticles are dissolved or dispersed in a solvent. The solvent to be used is not particularly limited as long as it has an appropriate dispersibility in the metal oxide nanoparticles. For example, benzene, toluene, xylene, cyclohexane, etc. can be used. The metal oxide nanoparticles coated with the coating agent (I) are highly dispersible in these solvents. If water or alcohol having 4 or less carbon atoms is used, secondary aggregation of nanoparticles may occur. Therefore, the present invention is completely different from the conventional method in which a highly hydrophilic metal oxide is dispersed and dissolved in water or the like. The concentration of the metal oxide may be appropriately adjusted, but is preferably about 0.1% by mass or more and 50% by mass or less.

 [0066] The amount of the other coating agent may be appropriately adjusted! However, it is usually 1% by mass or more and 60% by mass or less based on the metal oxide nanoparticles to which the coating agent (I) is bound. If it is less than 1% by mass, the amount of other coating agent may be insufficient, and the dispersibility in solvents other than nonpolar organic solvents such as toluene may not be improved. On the other hand, if it exceeds 60% by mass, the amount of the covering agent for the nanoparticles may become excessive. More preferably, they are 3 mass% or more and 50 mass% or less, More preferably, they are 5 mass% or more and 40 mass% or less.

 [0067] After the other coating agent is added to the dispersion of the metal oxide nanoparticles to which the coating agent (I) is bound, heat treatment is performed. The heating temperature may be adjusted as appropriate, but usually it is about 30 ° C or more and less than 180 ° C, more preferably 40 ° C or more and less than 150 ° C, more preferably 50 ° C or more and less than 130 ° C. To do. The reaction time may be adjusted as appropriate, but is usually 0.1 hour or more and less than 10 hours, more preferably 0.3 hour or more and less than 3 hours.

[0068] After completion of the reaction, the metal oxide nanoparticles bound with two or more coating agents may be recovered by distilling off the solvent under reduced pressure. Alternatively, a solvent having a low affinity for the nanoparticle should be added to the post-reaction solution containing the metal oxide nanoparticle to which two or more kinds of coating agents are bound. In this case, the metal oxide nanoparticles may be aggregated or precipitated and then collected by filtration.

 [0069] The obtained metal oxide nanoparticles are highly convenient because their surfaces are coated with two or more kinds of coating agents and exhibit high dispersibility in various solvents. The ratio of the coating agent bonded to the surface can be determined by, for example, NMR ^ vector, analysis result force using a CHN coder, elemental analyzer, or fluorescent X-ray analyzer.

 [0070] The metal oxide nanoparticle-containing composition of the present invention includes the metal oxide nanoparticles of the present invention described above. For example, the metal oxide nanoparticles of the present invention are dispersed in one or more selected from the group consisting of a solvent, a monomer, a polymer, and a plasticizer. The body can be mentioned. More specifically, examples of the composition of the present invention include coating compositions, thin film forming compositions, resin compositions, optical materials, and optical semiconductor encapsulants. There is no clear distinction between these coating compositions. For example, the coating composition can be used for the formation of a thin film, and the resin composition can be used as an optical material or an optical semiconductor sealing material. Can do.

 [0071] A dispersion in which the metal oxide nanoparticles of the present invention are dispersed in a solvent has transparency because the particles of the present invention have very high strength and are highly dispersible in various solvents. In addition, it is very useful because it has the characteristics of metal oxide nanoparticles.

 [0072] The definition of dispersion in the present invention is as follows. After adding metal oxide nanoparticles to a solvent at a concentration of 10% by mass and stirring for 10 minutes, a quantitative filter paper (No. 5c, manufactured by Advantech Toyo Co., Ltd.) is used. Quantity of particles recovered by filtration It shall be less than 3% by mass with respect to the amount of particles used.

[0073] The solvent used in the dispersion of the present invention may be selected from those in which the metal oxide nanoparticles of the present invention exhibit high dispersibility. For example, alcohols such as methanol, ethanol, n-propanol, isopropanol, and ethylene glycol; ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, propyl acetate, and propylene glycol monomethyl ether acetate Ethers such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; hydrocarbons such as benzene, toluene, xylene, ethylbenzene, and cyclohexane; dichloromethane, Examples thereof include halogenated hydrocarbons such as black mouth form; amides such as dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone; water; oils such as mineral oil, vegetable oil, wax oil, and silicone oil. One of these can be selected and used, or two or more can be selected and mixed for use. From the viewpoint of handleability, a solvent having a boiling point of 40 ° C or higher and 250 ° C or lower at normal pressure is suitable.

 [0074] The concentration of the metal oxide nanoparticles in the solvent can be appropriately set according to the use, but is usually 1% by mass or more and 60% by mass or less with respect to the dispersion. In general, if the concentration is less than 1% by mass, the solvent may be excessive. On the other hand, if it exceeds 60% by mass, it may be difficult to disperse uniformly and the dispersion may become cloudy. More preferably, it is 5 mass% or more and 55 mass% or less, More preferably, it is 10 mass% or more and 50 mass% or less.

 [0075] The dispersion of the present invention may be one in which the metal oxide nanoparticles of the present invention are dispersed in a monomer. When a polymerization reaction is performed using the dispersion, a composition in which metal oxide nanoparticles are dispersed in a polymer can be produced. The powerful monomer is not particularly limited. For example, a (meth) acrylic monomer such as (meth) acrylic acid ester; a styrene monomer such as styrene, butyltoluene, and dibutenebenzene; a bur system such as butyl chloride and vinyl acetate. And monomers.

 [0076] The content of the metal oxide nanoparticles in the monomer dispersion is not particularly limited. Usually, it is 2% by mass or more and 80% by mass or less. This is because such a concentration is low in viscosity and easy to handle. More preferably, it is 10 mass% or more and 60 mass% or less.

 [0077] When the monomer is liquid at normal temperature or immediately becomes liquid with slight heating, the particles of the present invention may be dispersed directly in the liquid monomer without using a solvent. However, when the viscosity of the monomer alone is high, the particles of the present invention may be dispersed after the viscosity is reduced by adding the above solvent. The concentration of metal oxide nanoparticles in these compositions is preferably 1% by mass or more and 60% by mass or less, more preferably 5% by mass or more and 55% by mass or less, more preferably 10% by mass or more and 50% by mass. % Or less is more preferable.

[0078] The dispersion of the present invention may be one in which the metal oxide nanoparticles of the present invention are dispersed in a polymer. The polymer that can be used in the composition is not particularly limited. Polymer resins, polycarbonate resins, polyester resins, polyether resins, polyamide resins, polyimide resins, polyolefin resins, polystyrene resins, polyolefin resins, epoxy resins, silicone resins, Thermosetting resin such as radically polymerizable resin can be used.

 [0079] The composition in which the metal oxide nanoparticles of the present invention are dispersed in a polymer may be produced by polymerizing the monomer dispersion in which the particles of the present invention are dispersed, The particles of the present invention may be mixed in a polymer and mixed well. Alternatively, the solvent may be removed after the polymer solution and the dispersion of the particles of the present invention are uniformly mixed, or after the dispersion of the particles of the present invention is uniformly mixed with the molten polymer. In the present invention, the polymer dispersion and the resin composition are not particularly distinguished, but the polymer dispersion mainly represents a material exhibiting fluidity or a material before molding, and the resin composition is mainly used after molding. The product shall be indicated.

 [0080] The proportion of the metal oxide nanoparticles in the polymer dispersion or resin composition of the present invention may be appropriately adjusted. For example, 0.1% by mass or more based on the entire dispersion or composition. 99 mass% or less.

 [0081] The shape of the polymer dispersion or the resin composition of the present invention is not particularly limited. For example, it may be formed into a plate, sheet, film, fiber or the like.

 [0082] The polymer constituting the polymer dispersion or the resin composition of the present invention is not particularly limited, and examples thereof include polyamides such as 6 nylon, 66 nylon, and 12 nylon; polyimide; polyurethane; polyethylene; Polyolefins; Polyesters such as PET, PBT, PEN; Polysalts, Bulls; Polysalts, Vinylidenes; Polyvinyl acetate; Polystyrenes; (Meth) acrylic resins; ABS resins; Silicone resins; Fluorine resins; Examples thereof include phenolic resins such as formalin resin and tarenol formalin resin; epoxy resins; amino resins such as urea resin, melamine resin and guanamine resin. In addition, soft resin such as polybutyral resin, polyurethane resin, ethylene vinyl acetate copolymer resin, ethylene (meth) acrylate copolymer resin, hard resin, organic binder, etc. Can be mentioned. These may be used alone or in combination of two or more.

[0083] In particular, among (meth) acrylic rosins, polyalcohols having no aromatic hydrocarbon structure (Meth) acrylic ester polymer is preferred. It does not have an aromatic hydrocarbon structure, thereby improving the light resistance, and improving the heat resistance of the cured product due to the hydroxyl group and ester group derived from polyalcohol, making it suitable as a material for optical lenses and lens sheets. It will be.

 [0084] Examples of (meth) acrylic acid esters of polyalcohol having an aromatic hydrocarbon structure include, for example, ethylene glycol, propylene glycol, 1,2 butanediol, 1,3-butanediol, and 1,4 butane. Diol, 1,5-pentanediol, 1,6 hexanediol, 1,7 heptanediol, 1,8 octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11 undecanediol, 1, 12-dodecandiol, 1,13 tridecanediol, 1,14-tetradecanediol, 1,15 pentadecanediol, 1,16 hexadecanediol, 3-methyl-1,5-pentanediol, 2,4 jetyl-1,5 pentane Diol, 1,2 cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, tricyclodecane dimethano , Cyclohexanedimethanol, hydrogenated bisphenol A, neopentyl glycol, butylethyl propanediol and other alkane diol (meth) acrylates; mono- or diesterified products of neopentyl dallicol with hydroxybivalic acid; Di (meth) acrylates such as β, β, β ', j8, tetramethyl-1,2,4,8,10-tetraoxaspiro [5,5] undecane1,3,9 genol. In addition, poly (meth) acrylic acid such as trimethylolethane, trimethylololepropane, trimethylonolevbutane, trimethylololehexane, ditrimethylonoreppan, pentaerythritol, dipentaerythritol, glycerin, polyglycerin, etc. Examples include esters.

[0085] Among these, polyalcohols having no j8 hydrogen relative to the hydroxyl group, for example, neopentyl dallicol, butylethyl propane diol, mono- or diesterified products of neopentyl glycol and hydroxybivalic acid, β, β , β ', j8, -Tetramethyl-2,4,8,10-tetraoxaspiro [5,5] undecane 3,9 Genol, trimethylol ethane, trimethylol propane, trimethylol butane, trimethylol hexane, ditrimethylol propane Polymers of (meth) acrylic acid such as pentaerythritol and dipentaerythritol are particularly preferred because they are excellent in resistance to deterioration and discoloration due to light. [0086] In addition, a poly (alcohol) (meth) acrylic acid ester derivative which does not have an aromatic hydrocarbon structure and further includes an ether structure is preferable because it is more excellent in light resistance. is there. For example, ethylene oxide, propylene oxide, butylene oxide force is also selected for polyalcohols such as neopentyldaricol, which do not have an aromatic hydrocarbon structure and do not have j8 hydrogen relative to the hydroxyl group. Polymers of (meth) acrylic acid, which are incapable of more than one kind of alkylene oxide, are most preferred because they are particularly resistant to discoloration and deterioration by light.

 [0087] The above (meth) acrylic acid esters may be used alone or in combination of two or more. Of the poly (alcohol) ester polymers of polyalcohols having no aromatic hydrocarbon structure, those containing sulfonic acid groups and Z or sulfonic acid ester groups are preferred because of their excellent light resistance. . The content of the strong sulfonic acid group or sulfonic acid ester is preferably 10 ppm or less, more preferably 50 ppm or less, more preferably 30 ppm or less in terms of sulfur atom.

[0088] It does not have an aromatic hydrocarbon structure! /, The production method of the (meth) acrylic acid ester of polyalcohol is not particularly limited, but for example, by a dealcoholization reaction of polyalcohol and (meth) acrylic acid ester And a production method (a transesterification method) and a production method (a dehydration condensation method) by a dehydration reaction between a polyalcohol and (meth) acrylic acid.

[0089] When transesterification is performed, the molar ratio of polyalcohol to (meth) acrylic acid ester (hydroxyl group in polyalcohol: (meth) acrylic acid ester) is preferably 1: 1 to 1:20. 1: 1.5 to 1:10 is more preferable, and 1: 2 to 1: 5 is more preferable. Examples of the catalyst include alkali metal alcoholates, magnesium alcoholates, aluminum alcoholates, titanium alcoholates, dibutyltin oxides, anion exchange resins and the like. The catalyst is used in an amount of 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, and more preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the total charge of the reaction. preferable. It is preferable to remove the catalyst after the reaction. Examples of the solvent include pentane, cyclopentane, hexane, cyclohexane, methylcyclohexane, heptane, cycloheptane, octane, isooctane, benzene, toluene, and cymene. The amount of solvent used is preferably 1 to 70 parts by weight and more preferably 5 to 50 parts by weight with respect to 100 parts by weight of the total charge of the reaction. 10 to 30 parts by mass is more preferable. The reaction temperature is preferably 50 to 150 ° C, more preferably 70 to 140 ° C, and still more preferably 90 to 130 ° C.

[0090] When the dehydration condensation method is performed, the charged molar ratio of polyalcohol to (meth) acrylic acid (hydroxyl group in polyalcohol: (meth) acrylic acid) is preferably 1: 1 to 1: 5, 1. 01 to 1: 2 is more preferred 1: 1. 05 to 1: 1.5 is more preferred. Examples of the catalyst include acid catalysts such as sulfuric acid, hydrochloric acid, phosphoric acid, ρ-toluenesulfonic acid, benzenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, and cation exchange resin. Among these, a cation exchange resin is preferred in order to sufficiently exhibit the effects of the present invention. Examples of the cation exchange resin include Amberlist (registered trademark) and Amberlite (registered trademark) manufactured by Rohm 'and' Haas, and Diaion (registered trademark) manufactured by Mitsubishi Igaku. . Cation exchange resin should be washed thoroughly with an organic solvent such as toluene or methanol and water before use, and force should be used so that the xio component does not distill. More preferred. The amount of catalyst used is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, with respect to 100 parts by weight of the total charge of the reaction. Further preferred. In addition, it is preferable to remove a catalyst after reaction. Examples of the solvent include pentane, cyclopentane, hexane, cyclohexane, methylcyclohexane, heptane, cycloheptane, octane, isooctane, benzene, toluene, and cymene. The amount of the solvent used is preferably 1 to 70 parts by mass, more preferably 5 to 50 parts by mass, and even more preferably 10 to 30 parts by mass with respect to 100 parts by mass of the total charge of the reaction. The reaction temperature is preferably 50 to 150 ° C, more preferably 70 to 140 ° C, and even more preferably 90 to 130 ° C.

 [0091] The polymer dispersion or resin composition of the present invention may contain metal oxide nanoparticles and other additive components of resin. Examples of such additive components include curing agents, curing accelerators, colorants, mold release agents, coupling agents, silicone compounds, reactive diluents, plasticizers, stabilizers, flame retardant aids, and crosslinking agents. An agent etc. can be mentioned.

[0092] A curing agent may be required when a thermosetting resin is used. For example, when an epoxy resin is used, polyamides, aliphatic polyamines, cycloaliphatic polyamines, aromatic polyamines or amines modified with a part thereof, acid anhydrides, dicyandia Preferably used are novolak-based curing agents such as amides, imidazoles, aminimides, hydrazides, phenol novolacs and talelen novolacs. In addition, when phenol resin is used, urotropin or formal is preferably used. The amount of these curing agents may be adjusted as appropriate according to the amount of the resin.

 [0093] The plasticizer is added to further improve the processability of the resin composition, and the type thereof can be selected according to the resin. For example, when using epoxy resin, it is preferable to use a polyglycol plasticizer.

 [0094] The polymer dispersion and the resin composition of the present invention are fine and highly dispersible, and have high transparency because the metal oxide nanoparticles are uniformly dispersed. Specifically, the difference between the visible light transmittance of the resin composition of the present invention and the visible light transmittance of a composition produced in the same manner except that the particles of the present invention are not contained is ± 30% or less. More preferably ± 20% or less, more preferably ± 10%. The difference in haze between the two compositions is preferably ± 10% or less, more preferably ± 3% or less, and even more preferably ± 1% or less. In addition, as the resin composition, those having a visible light transmittance of 80% or more, a haze of 10% or less, and a visible transmittance of 85% or more and a haze of 5% or less are excellent in transparency and useful. Such a resin composition can be easily produced using the metal oxide nanoparticles of the present invention.

[0095] The type of plasticizer used in the dispersion of the present invention is not particularly limited. For example, phosphate plasticizers such as tributyl phosphate and 2-ethylhexyl phosphate; dimethyl phthalate, dibutyl phthalate Phthalic acid ester plasticizers such as butyl oleate, glycerol monooleic acid esters, etc .; Aliphatic monobasic acid ester plasticizers such as dibutyl adipate and diethyl sebacate 2-aliphatic acid esters such as 2-ethylhexyl Plasticizers; Dihydric alcohol ester plasticizers such as diethylene glycol dibenzoate and triethylene glycol di-2-ethyl butyrate; Oxic acid ester plasticizers such as methyl acetylyl ricinoleate and tributyl acetyl citrate; Chlorinated paraffins ; polypropylene glycol adipate, 1, ₃ Buchirenguri Ruajipeto, weight average molecular weight of 100

Polyester plasticizers such as co-condensation polymers of about 0 to 15000; epoxy plasticizers such as epoxy stearates and epoxy triglycerides; stearic acid plasticizers; chlorinated biphenyl, 2--trobiphenol, dino- Lunaphthalene, o-Toluenesulfone Other plasticizers such as tilamide, camphor, methyl abietic acid can be used.

 [0096] The concentration of the metal oxide nanoparticles in the plasticizer can be appropriately set depending on the application. The particles of the present invention may be dispersed in a mixture of a plasticizer and a solvent. The amount of the plasticizer to be used may be appropriately adjusted! However, for example, the ratio of the particles of the present invention to the plasticizer may be about 0.01 or more and 5 or less by mass ratio.

 [0097] The dispersion of the present invention may be dispersed in a mixture of two or more selected from the group consisting of a solvent, a monomer, a polymer, and a plasticizer. For example, the particles of the present invention are dispersed in a solvent / monomer mixture, a solvent / plasticizer mixture, or a solvent / monomer / plasticizer mixture. These are useful as materials for rosin compositions

[0098] The dispersion of the present invention described above can be used by further adding other components. For example, a binder can be added to the dispersion of the present invention to form a coating composition. Since the coating composition contains the highly dispersible metal oxide nanoparticles according to the present invention, a highly functional and highly functional coating film can be obtained.

 [0099] The type of binder used in the coating composition of the present invention is not particularly limited. For example, thermoplastic, thermosetting, ultraviolet curable, electron beam curable, moisture curable binders; synthetic binders, organic binders or inorganic binders such as natural resin; solvent soluble type, water soluble type, emulsion type, A dispersion type binder can be used.

 [0100] Examples of the synthetic resin that can be used as a cylinder include alkyd resin, amino resin, bur resin, acrylic resin, epoxy resin, polyamide resin, polyurethane resin, thermosetting unsaturated polyester. Resin, phenol resin, chlorinated polyolefin resin, silicone resin, acrylic silicone resin, fluorine resin, xylene resin, petroleum resin, ketone resin, oral resin modified maleic acid resin, liquid polybutadiene, coumarone Examples include fats.

 [0101] Examples of natural rosin that can be used as a noinda include shellac, rosin, ester gum, hardened rosin, decolorized shellac, and white shellac.

[0102] Examples of water-soluble binders include water-soluble alkyd resin, water-soluble acrylic modified Water-soluble oil-free alkyd resins such as alkyd resins and water-soluble polyester resins, water-soluble acrylic resins, water-soluble epoxy ester resins, and water-soluble melamine resins.

 [0103] Examples of the emulsion type binder include (meth) acrylic acid alkyl copolymer dispersions, acetoacetate succinic acid emulsion emulsion, acetoacetate copolymer cohesive resin emulsion, ethylene acetate butyl copolymer cohesive resin emulsion, acrylate acrylic acid ( Co-polymerized resin emulsion, styrene acrylate (co) polymer resin emulsion, epoxy resin emulsion, urethane resin emulsion, acrylic silicone emulsion, fluorine resin emulsion, and the like.

 [0104] Examples of the inorganic binder include metal alkoxides such as silica gel, alkali key acid, and silicon alkoxide; condensates obtained by hydrolysis thereof; phosphates and the like.

 [0105] The composition of the present invention further comprises a curing agent such as a crosslinking agent; a curing catalyst such as a curing aid; a plasticizer; an antifoaming agent; a repelling agent; a thixotropic agent; Flame retardant; Pigment moistening agent; Antifungal agent; Algae inhibitor; Anticorrosive agent; Antifungal agent; Dye; Pigment; A coating composition containing polyisocyanate as a curing agent is highly versatile. Conventionally, there are materials called hard coat agents that improve the surface hardness of films, sheets, plates, and lenses. Add a hard coating agent to the coating composition of the present invention.

 [0106] Examples of the method for producing a coating composition according to the present invention include a method in which a metal oxide nanoparticle is added to a solvent to form a slurry, and then a noinder is mixed.

 [0107] The coating composition of the present invention can be applied to the surface of a substrate made of an inorganic material such as glass or earthenware, or an organic material such as greaves. In particular, since the nanoparticles of the present invention are extremely excellent in dispersibility, a coating film obtained by applying the coating composition of the present invention to the surface of a substrate made of an organic material is excellent in flexibility. Moreover, the coating film obtained from the coating composition containing the light stabilizer has high weather resistance.

[0108] The shape of the substrate is not particularly limited, and examples thereof include a film shape, a sheet shape, a plate shape, and a fiber shape. In particular, the coating composition of the present invention is a film or fiber. Useful for any substrate application.

 [0109] The material of the resin used as the substrate is not particularly limited and can be appropriately selected. For example, LDPE, HDPE, amorphous polyethylene, polypropylene such as OPP (oriented polypropylene), CPP (crystallized polypropylene) and polyolefins such as polyisobutylene; EVA (ethylene'vinyl acetate copolymer); polystyrene; soft or hard EVOH (ethylene butyl alcohol copolymer system; PVA (vinylon); PVDC (polyvinylidene chloride): Polyester such as polyethylene terephthalate, polyethylene naphthalate, polybutylene naphthalate; Polycarbonate; Polyurethane; Polyamide Polyimide; Polyacrylonitrile; Polysulfone; Polyethersulfone; Polyphenylenesulfite; Polyarylate; Polyetherimide; Aramid; Poly (meth) acrylic; Polyetheretherketone; Lafluoroethylene, ethylene copolymer, tetrafluoroethylene 'hexafluoropropylene copolymer, polytetrafluoroethylene, polytrifluoroethylene, polyvinylidene fluoride, polyfluoride butyl, tetrafluoroethylene' Per Fluorocarbon resins such as fluoroalkyl butyl ether copolymer, tetrafluoroethylene hexafluoropropylene 'perfluoroalkyl butyl ether copolymer, polychloroethylene, etc. can be used. Of these, among these, fluorine-based resin, polyester-based resin, (meth) acrylic acid-based resin, and polycarbonate-based resin are preferably used.

 [0110] PMMA, MMA-styrene random copolymer, polycarbonate, transparent polypropylene, MMA and α-methino are used for applications that require extremely high visible light transparency and transparency, such as optical lenses. Copolymer with restyrene or cyclohexenoremethalate, ABS resin modified type, polystyrene, polyarylate, polysulfone, polyethersulfone, transparent epoxy resin, poly-4-methylpentene 1, fluorinated polyimide Various types of resins such as amorphous fluorine resin, transparent phenoxy resin, amorphous nylon resin, and fluorene resin can be used as the base material.

[0111] In consideration of environmental problems, a base material made of biodegradable resin may be used. Examples of biodegradable resins include poly-3-hydroxybutyrate ester, chitin 'chitosan-based resin, polyamino acid-based resin, cellulose-based resin, poly-strength prolatatone-based resin, and alginic acid-based resin. Examples thereof include fats, polyvinyl alcohol-based resins, aliphatic polyester-based resins, saccharide-based resins, polyurethane-based resins, and polyether-based resins.

 [0112] Examples of the substrate include those in which a UV absorbing film is disposed in advance on the above-mentioned substrate, and those in which a primer layer is disposed in advance for the purpose of improving the adhesion between the coating film composed of the coating composition and the substrate, etc. It's okay.

 [0113] The method for applying the coating composition is not particularly limited, and examples thereof include a dubbing method, a roll coater method, a flow coat method, a screen printing method, a bar coater method, a spin coater method, a brush coating method, and a spray method. Can be used. Also, the dry film thickness obtained by applying the coating composition is not particularly limited, but is preferably 0.5 m or more and 100 m or less, more preferably 1 μm or more and 30 μm or less.

 [0114] After the coating composition is applied and dried to form a film, the film must be cured in terms of water resistance, solvent resistance, chemical resistance such as acid resistance and alkali resistance, and scratch resistance. Is preferred. Examples of the film curing method include thermal curing including room temperature curing, moisture curing, ultraviolet curing, and electron beam curing.

 [0115] The laminated glass can be obtained by using a transparent plate such as a glass plate on which an intermediate film is formed by the coating composition. Laminated glass can be produced by laminating the transparent plate and a separate transparent plate easily through an adhesive sheet. Adhesives for adhesive sheets include soft resin or hard resin such as polyvinyl butyral resin, polyurethane resin, ethylene vinyl acetate copolymer resin, and ethylene- (meth) acrylate copolymer resin. Fats can be mentioned, and a soft resin is preferable. The thickness of the adhesive sheet is preferably about 0.1 to 2 mm, more preferably about 0.5 to 1 mm.

 [0116] The film of the present invention is a film containing the metal oxide nanoparticles of the present invention as essential constituent components. The thin film of the present invention is useful, for example, as various functional films such as a high refractive index film, an antireflection film, a heat conductive film, and an ion conductive film, and as an undercoat film material for forming a superconductive film.

 [0117] The film of the present invention includes, for example, (1) a film in which the particles of the present invention are dispersed in a resin, (2) a film in which only the particles of the present invention have a force, and (3) a film of (2) is further sintered. And a film obtained by sintering only a part of the film of (4) and (2).

[0118] The film of (1) in which the particles of the present invention are dispersed in the resin has the above-described polymer dispersion of the present invention and It can be produced from a rosin composition. The film of (2), in which only the particles of the present invention are effective, can be produced from a dispersion in which the particles of the present invention are dispersed in a solvent. The film of (3) can be produced by firing the whole of (2) at a high temperature, and the film of (4) can be produced by firing a part of the film of (2) such as only one side. Usually, in the films of (1) and (2), the metal oxide nanoparticles of the present invention are present while substantially maintaining their form. On the other hand, the sintered part of the film (3) and the film (4) is accompanied by structural changes such as changes in the crystallite diameter of the particles. It can be a different polycrystalline or single crystal film.

 [0119] The form of the film according to the present invention is not particularly limited. For example, it may be a film formed on a desired substrate surface. In addition, the film of the present invention includes both the film itself and, when formed on a base material, any one composed of the film and the base material. Further, it may be in a form that continuously spreads in a desired area on the surface of the substrate (hereinafter sometimes referred to as a “continuous film”), or may be a desired shape on the surface of the substrate. It may be in a form that is discontinuously present in the area portion (hereinafter sometimes referred to as “discontinuous film”). In the discontinuous film, the constituent components of the film are partially present on the surface of the base material, but their size, area, thickness, shape, and the like are not particularly limited. Specific forms of the discontinuous film include, for example, a form in which the constituent components of the film are present in the form of fine dots on the substrate surface, a form in which the so-called sea-island structure exists, and a striped pattern Forms that are present in these, and forms that combine these forms.

 [0120] When the continuous film and the discontinuous film are composed only of metal oxide nanoparticles, the structure of these films is not particularly limited. For example, a porous structure having a space of a desired size may be used, or a dense structure may be used. A dense structure is preferable from the viewpoint of the UV blocking property and the low transparency loss due to scattered visible light. In the discontinuous film, the film structure as described above may be included in all of the partially existing films, or only a part thereof.

[0121] The material of the substrate that can be used in the film of the present invention is not particularly limited. For example, inorganic materials such as ceramic glass; polyester resin such as PET, PBT, PEN, polycarbonate resin, polyphenylene sulfide resin, polyethersulfone resin, polyetherimide resin, polyimide resin, amorphous Polyolefin resin, polyarylate resin, aramid resin Heat resistant resin such as oil, polyetheretherketone resin, liquid crystal polymer; (meth) aryl resin, PVC resin, PVDC resin, PVA resin, EVOH resin, polyimide resin, polyimide resin, Fluorine resins such as PTFE, PVF, PGF, and ETFE; epoxy resins; polyolefin resins; those obtained by vapor-depositing aluminum, alumina, silica, etc .; metals are preferred.

 [0122] The shape of the substrate forming the film of the present invention is not particularly limited. For example, a film, a sheet, a plate, a fiber, a laminated body, etc. are mentioned, What is necessary is just to select according to a use, a use purpose, etc. The base material is not limited in terms of function, and may be selected according to, for example, the use or purpose of use which may be optically transparent or opaque.

 [0123] The film of the present invention preferably has high transparency. Specifically, the haze is preferably 10% or less, more preferably 2% or less, and even more preferably 1% or less.

 [0124] The method for producing the film of the present invention is not particularly limited. For example, the solvent dispersion of the present invention may be applied to a substrate and dried after applying the resin dispersion. A method for applying the dispersion of the present invention is not particularly limited, and for example, a bar coater method, a roll coater method, a knife coater method, a die coater method, a spin coat method, a spray method, a dating method, and the like can be used. .

 [0125] The polymer in which the metal oxide nanoparticles of the present invention are dispersed can be used as various materials because the particles themselves are fine and excellent in dispersibility, and the particles are uniformly dispersed. For example, it can be used widely such as a transparent film, an optical material, and a catalyst material.

In particular, since tetragonal crystal zirconium oxide has a high refractive index, a polymer composition containing nanoparticles that also contain tetragonal zirconium oxide is useful as an optical material. Examples of such optical materials include substrates, light diffusing films, light diffusing plates, antiglare films, polarizing plates, viewing angle correction films, antireflection films, protective films, and other display components; disk substrates, pickup lenses, protective lenses Optical recording media such as films; spectacle lenses, optical equipment lenses, pickup lenses, optoelectronic lenses, laser lenses, automotive lamp lenses, OHP lenses, etc .; one optical fiber; optical waveguide; Optical adhesive; resist; optical disk substrate; coating agent; Can be used.

 [0127] When the particles of the present invention that also have an acid-zirconium force are dispersed in a polymer and used as an optical material, it is preferable to use a cycloolefin resin as the polymer.

 [0128] Cyclorefin rosin is composed of a polymer having an aliphatic cyclic structure in the main chain. Examples of cycloolefin resins used in the present invention include norbornene, dicyclopentagen, tetracyclododecene, ethyltetracyclododecene, ethylidenetetracyclododecene, tetracyclotrideca-2, 4, 6, 11— Polycyclic unsaturated hydrocarbons such as tetraene and derivatives thereof; cyclobutene, cyclopentene, cyclohexene, 3,4-dimethylcyclopentene, 3-methylcyclohexene, 2- (2 methylbutyl) 1-cyclohexene, cyclootaten, 3a, 5, 6, 7a-tetrahydro-4,7 methanol 1H-indene, unsaturated hydrocarbon having a monocyclic structure such as cycloheptene, cyclopentagen, cyclohexagen, and derivatives thereof. The cycloolefin may have a functional group such as a hydroxyl group, a carboxyl group, an alkoxyl group, an epoxy group, a glycidyl group, an oxycarbonyl group, a carbonyl group, an amino group, an ester group, or a carboxylic anhydride group.

 [0129] The cycloolefin resin in the present invention may be an addition-polymerized monomer other than cycloolefin. Examples of the monomer capable of addition copolymerization include ethylene such as ethylene, propylene, 1-butene and 1 pentene or α-olefin; 1,4 monohexagen, 4-methyl-1,4 monohexagen, 5— Examples include gens such as methyl-1,4 hexagen and 1,7-octagen.

[0130] The cycloolefin resin in the present invention is obtained by an addition polymerization reaction or a metathesis ring-opening polymerization reaction. Polymerization is performed in the presence of a catalyst, and examples of the addition polymerization catalyst include a polymerization catalyst composed of a vanadium compound and an organoaluminum compound. As a catalyst for ring-opening polymerization, for example, a polymerization catalyst comprising a metal halide such as ruthenium, rhodium, palladium, osmium, iridium, platinum, nitrate or acetylacetone compound, and a reducing agent, or titanium, vanadium, zirconium And a polymerization catalyst comprising a metal halide such as tandastene or molybdenum or a acetylylacetone compound and an organoaluminum compound. [0131] The cycloolefin resin in the present invention is preferably one in which the unsaturated bond in the molecule is changed to a saturated bond by polymerizing or copolymerizing cycloolefin and then hydrogenating it. The hydrogenation reaction is carried out by blowing hydrogen in the presence of a known hydrogenation catalyst.

 [0132] As the cycloolefin resin in the present invention, norbornene-based polymers can also be preferably used. As the norbornene-based polymer, a polymer obtained by copolymerizing a norbornene-based monomer preferably having a norbornene skeleton as a repeating unit and other monomers can also be used. Examples of other monomers copolymerizable with the norbornene-based monomer include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1— 1-hexadecene, 1-octadecene, 1 eicosene and other α-olefins having 2 to 20 carbon atoms, and derivatives thereof; cyclobutene, cyclopentene, cyclohexene, cyclo-octene, 3a, 5, 6, 7a —Tetrahydro-4,7 Metanol 1H—Cyclorefin such as indene and derivatives thereof; 1,4 monohexagen, 4-methyl-1,4 monohexagen, 5-methyl-1,4 monohexagen, 1,7— A non-conjugated gen such as Octagen is used.

 [0133] As the cycloolefin resin in the present invention, specifically, trade names "Zeonex 480", "Zeonex 480R", "Zeonex E48R", "Zeonex 330R", "Zeonor" manufactured by ZEON Corporation; JSR; The product names “Aton” manufactured by Mitsui Chemicals, Inc .; the product names “APL 8008T”, “APL6509T”, “APL6013T”, “APL5014DP”, “APL6015T”, and the like manufactured by Mitsui Chemicals are preferably used.

 [0134] The molecular weight of the cycloolefin resin in the present invention is a polyisoprene or polystyrene equivalent weight average molecular weight measured by a gel 'permeation' chromatographic method using cyclohexane as an eluent, and is 5000 to 500,000. Power to do S is preferable. The weight average molecular weight is preferably 8000 to 200,000 force S, more preferably 10,000 to 100,000 force S. In addition, when the cycloolefin rosin to be measured does not dissolve in cyclohexane, toluene may be used as an eluent.

[0135] In the optical material of the present invention, the amount of the cycloolefin resin and the acid / zirconium nanoparticles combined is 25 parts of the acid / zirconium nanoparticles to 100 parts by mass of the cycloolefin resin. Not less than part by mass. If the content is less than 25 parts by mass, the refractive index of a molded article made of the composition for optical materials may be lowered. A more preferable upper limit value of the content of oxyzirconium particles is 200 parts by mass, and 100 parts by mass is most preferable. The lower limit is 40 parts by mass, and 50 parts by mass is most preferable.

[0136] As described above, the zirconium oxide particles have a high refractive index! ,. In addition, the nanoparticle of the present invention has very high dispersibility with respect to polymers and the like. Therefore, the composition in which the nanoparticles of the present invention having an acid-zirconium force are dispersed in epoxy resin or the like exhibits high light transmittance and a high refractive index, and is thus very useful as an optical semiconductor encapsulating material. is there.

[0137] The epoxy resin is generally cured with a curing agent. The total compounding amount of the epoxy resin and the curing agent in the optical semiconductor sealing material of the present invention is preferably in the range of 90 to 20% by mass in the composition. If the blending amount exceeds 90% by mass, the refractive index of the sealing material obtained from the composition may be lowered. On the other hand, if the blending amount is less than 20% by mass, the viscosity of the composition becomes high and workability may be lowered. The total blending amount of epoxy resin and curing agent is more preferable. The upper limit is 70% by mass, and 50% by mass is most preferable. Further, the more preferable lower limit of the amount is 30% by mass, and 40% by mass is most preferable.

 [0138] The compounding amount of the nanoparticles in the sealing composition of the present invention is preferably in the range of 10 to 80 mass% with respect to the entire composition. If the amount is less than 10% by mass, the refractive index of the encapsulant may be lowered. On the other hand, if the blending amount exceeds 80% by mass, the viscosity of the composition increases, and workability may be reduced. A more preferable upper limit of the compounding amount of the nanoparticles is 70% by mass, and 60% by mass is most preferable. Further, the above blending amount is more preferable V, the lower limit is 30% by mass, and 50% by mass is most preferable.

 [0139] When the nanoparticles of the present invention are used as an optical semiconductor encapsulant, a crystal stabilizer may be contained in the acid zirconium particles for crystal stability. Examples of the above-mentioned crystal stabilizing material include alkaline earth metal oxides such as MgO and CaO, lanthanides, and rare earth such as Y 2 O.

 twenty three

 Examples include metal oxides. The content of the crystal stabilizer is preferably 0.01% by mass or more, more preferably 0.1% by mass or more.

Example [0140] Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples as well as the present invention, and is appropriately modified within a range that can meet the purpose described above and below. It is also possible to carry out with addition, and they are all included in the technical scope of the present invention.

 [0141] The method for measuring physical properties of each metal oxide nanoparticle is as follows.

[0142] Test Example 1 X-ray powder diffraction

 The crystal structure of the metal oxide nanoparticles was measured using a fully automatic multipurpose X-ray diffractometer (XPert Pro, manufactured by Spetatris). The measurement conditions are as follows.

 X-ray source: CuKa (0. 154nm)

 X-ray output setting: 45kV, 40mA

 Step size: 0.017 °

 Scan step time: 5. 08 seconds,

 Measuring range: 5 ~ 90 °

 Measurement temperature: 25 ° C

 [0143] The obtained X-ray diffraction chart was analyzed with analysis software (XRayCrystal), and the C value indicating crystallinity was calculated from the formula (1).

 [0144] Test Example 2 Average particle size

 The metal oxide nanoparticles were observed with an ultra-high resolution field emission scanning electron microscope (S-4800, manufactured by Hitachi High-Technologies Corporation). Arbitrarily 100 particles observed in a magnified manner were selected, the length of each particle in the major axis direction was measured, and the average value was taken as the average particle size.

 Production Example 1 Production of acid-zirconium nanoparticles coated with neodecanoic acid

 Sodium hydroxide (80 g, manufactured by Kishida Chemical Co., Ltd., special grade) was added to 40 ° C pure water (640 g) with stirring and dissolved. Next, neodecanoic acid (396.9 g, manufactured by Japan Epoxy Resin Co., Ltd.) was added with stirring to prepare a sodium neodecanoate aqueous solution. Next, the solution was heated to 80 ° C, and under stirring, zirconium oxychloride (585. 99 g, ZrOCl · 8Η 0, first rare element

 twenty two

Zircosol ZC-20) manufactured by Chemical Industry Co., Ltd. was added over 20 minutes. When stirring was continued for 1.5 hours at 80 ° C, white and viscous zirconium neodecanoate was produced. After removing the aqueous phase, the zirconium neodecanoate was sufficiently washed with pure water. Then Tetradecane (92 g) was added to the zirconium neodecanoate and stirred.

[0146] Pure water (400 g) was mixed with the obtained zirconium neodecanoate monotetradecane solution.

 The mixture was charged into an autoclave equipped with a stirrer, and the atmosphere in the reaction vessel was replaced with nitrogen gas. Thereafter, the reaction mixture was heated to 180 ° C. and reacted for 3 hours to synthesize zirconium oxide particles. The pressure in the container when reacted at 180 ° C was 0.9 MPa. The solution after the reaction was taken out, the precipitate accumulated at the bottom was filtered off, washed with acetone and dried. When the precipitate (80 g) after drying was dispersed in toluene (800 mL), a cloudy solution was obtained. Next, as a purification step, filtration was again performed using a quantitative filter paper (No. 5C, manufactured by Advantech Toyo Co., Ltd.) to remove coarse particles and the like in the precipitate. Next, the toluene obtained by concentrating the filtrate under reduced pressure was removed to collect white zirconium oxide nanoparticles.

 [0147] When the crystal structure of the acid-zirconium nanoparticles was confirmed with an X-ray diffractometer, diffraction lines attributed to tetragonal and monoclinic crystal structures were detected. From the intensity of the diffraction lines, it was confirmed that the crystal structure was mainly tetragonal and contained a slight monoclinic crystal. The C value determined from the obtained X-ray diffraction chart was 39.4. Therefore, it was found that the crystallinity of the above-mentioned zirconium oxide nanoparticles was extremely high.

 [0148] Further, when the particle diameter of the zirconium oxide nanoparticles was measured by FE-SEM, the average particle diameter was 5 nm. Furthermore, analysis by infrared absorption spectrum revealed absorption due to C—H and absorption derived from COOH. The absorption is considered to be derived from neodecanoic acid covering the acid-zirconium nanoparticle.

[0149] Furthermore, the mass reduction rate of the zirconium oxide nanoparticles when the temperature was raised to 800 ° C at a rate of 10 ° CZ in an air atmosphere was measured by TG-DTA (thermogravimetric differential thermal analysis). , it became a 19 mass _^0/0 rate of decrease. Therefore, it was confirmed that the neodecanoic acid covering the acid-zirconium nanoparticles was 19% by mass of the whole particles.

 [0150] Also, the particle size distribution is measured and converted from the formula: σ Zx X 100 [where σ is the standard deviation of the particle size distribution of the particles, and X is the 50% cumulative diameter (nm) of the particles] The coefficient was calculated to be 20%. Therefore, it was found that there was little variation in the particle size of the nanoparticles.

[0151] Production Example 2 Coated with neodecanoic acid and 3-methacryloxypropyltrimethoxysilane Production of zirconium oxide nanoparticles

 A transparent solution was prepared by dispersing the zirconium oxide nanoparticles (10 g) obtained in Production Example 1 in toluene (90 g). To the solution, 3-methacryloxypropyl trimethoxysilane (1.5 g, manufactured by Shin-Etsu Chemical Co., Ltd., KBM-503) was added as a surface treatment agent, and the mixture was heated to reflux at 90 ° C. for 1 hour. Next, n-xane was added to the solution after the reflux treatment to agglomerate the dispersed particles to make the solution cloudy. Aggregated particles were separated from the white turbid solution with filter paper, and then vacuum-dried at room temperature to prepare acid-zirconium nanoparticles surface-treated with neodecanoic acid and 3-methacryloxypropyltrimethoxysilane.

[0152] When the crystal structure of the resulting coated oxide / zirconium nanoparticles was confirmed with an X-ray diffractometer, diffraction lines attributed to tetragonal and monoclinic crystal structures were detected. From the intensity of the diffraction lines, it was confirmed that the crystal structure was mainly tetragonal and slightly monoclinic. Further, when the particle diameter of the zirconium oxide nanoparticles was measured by FE-SEM, the average particle diameter was 5 nm. Furthermore, when analyzed by infrared absorption spectrum, absorption derived from Si—O—C was observed in addition to absorption derived from CH and COOH. These absorptions are thought to originate from neodecanoic acid and 3-methacryloxypropyltrimethoxysilane that coat the zirconium oxide nanoparticles. TG-DT

When the mass reduction rate of acid-zirconium nanoparticles when the temperature was raised to 800 ° C at a rate of 10 ° CZ in an air atmosphere by A (thermogravimetric differential thermal analysis), the decrease of 18% by mass was measured. Became a rate. Therefore, it was confirmed that neodecanoic acid and 3-methacryloxypropyltrimethoxysilane, which were coated with zirconium oxide nanoparticles, accounted for 18% by mass of the whole particles.

[0153] Further, the nanoparticles were analyzed with a fluorescent X-ray analyzer, and the Si content was measured to quantify 3-methacryloxypropyltrimethoxysilane in the coating layer. Furthermore, the total C content in the nanoparticles was measured using a CHN coder analyzer, and the amount of neodecanoic acid derived from the amount of neodecanoic acid was calculated by subtracting the amount of C derived from 3-methacryloxypropyltrimethoxysilane. Asked. As a result, the abundance ratio of 3-methacryloxypropyltrimethoxysilane to neodecanoic acid in the coating layer was 1.5 in terms of molar ratio. Further, the conversion coefficient obtained from the particle size distribution was 20% as in the case of the particles of Production Example 1 above. Production Example 3 Production of zirconium oxide nanoparticles coated with neodecanoic acid and hydroxystearic acid

 The neodecanoic acid-zirconium nanoparticles (10 g) obtained in Production Example 1 were dissolved in toluene (9 Og), and hydroxystearic acid (1.5 g) was added. The reaction mixture was heated to reflux at 100 ° C. for 1 hour. The obtained reaction mixture was concentrated under reduced pressure to obtain acid-zirconium nanoparticles coated with neodecanoic acid and hydroxystearic acid.

 [0155] The mass reduction rate of the obtained acid-zirconium nanoparticles was measured by TG-DTA (thermogravimetric differential thermal analysis) at a rate of 10 ° CZ in an air atmosphere to 800 ° C. The weight loss rate was 29.5% by mass. Therefore, it was confirmed that the amount of neodecanoic acid and hydroxystearic acid covering the zirconium oxide nanoparticles was 29.5% by mass of the whole particles. The ratio of hydroxystearic acid to neodecanoic acid in the nanoparticles was 0.45 molar ratio. The conversion coefficient obtained from the particle size distribution was 20% as in the case of the particles of Production Example 1.

 [0156] Production Example 4 Production of acid-zirconium nanoparticles coated with neodecanoic acid and 2- [2- (2-methoxyethoxy) ethoxy] acetic acid

 The neodecanoic acid-zirconium nanoparticles (10 g) obtained in Preparation Example 1 were dissolved in toluene (9 Og), and 2- [2- (2-methoxyethoxy) ethoxy] acetic acid (1.5 g) was added. . The reaction mixture was heated to reflux at 80 ° C for 1 hour. The obtained reaction mixture was concentrated under reduced pressure to obtain acid-zirconium nanoparticles coated with neodecanoic acid and 2- [2- (2-methoxyethoxy) ethoxy] acetic acid.

[0157] The mass reduction rate of the obtained acid-zirconium nanoparticles was measured by TG-DTA (Thermogravimetric differential thermal analysis) in the same manner as in Production Example 3 above. The weight loss rate was 29.6% by mass. . Therefore, it was confirmed that the amount of neodecanoic acid and 2- [2- (2-methoxyethoxy) ethoxy] acetic acid covering the acid-zirconium nanoparticles was 29.6% by mass of the whole particles. . The abundance ratio of 2- [2- (2-methoxyethoxy) ethoxy] acetic acid to neodecanoic acid in the nanoparticle was 0.76 in molar ratio. Further, the conversion coefficient obtained for the particle size distribution force was 20% as in the case of the particles of Production Example 1. [0158] Test Example 3 Solubility test

 The solubility of the acid-zirconium nanoparticles in Production Examples 1 to 4 in various solvents was tested. Specifically, each zirconium oxide nanoparticle (5 g) is added to water, ethanol, ethyl oxalate, cyclohexanone, methyl isobutyl ketone (MIBK), methyl methacrylate (MMA) or toluene (50 g). After that, the mixture was stirred at room temperature for 15 minutes, and the state was visually observed. The results are shown in Table 1. In the table, ○ indicates the case where the particles are completely dissolved to become a transparent solution, △ indicates the case where the particles are not transparent but the particles are dispersed, and X indicates the case where the particles are aggregated. .

 [0159] [Table 1]

[0160] As shown above, the acid-zirconium nanoparticles coated only with neodecanoic acid (Production Example 1) showed solubility in toluene alone. Insoluble in other organic solvents .

[0161] On the other hand, the acid-zirconium nanoparticles of the present invention coated with two kinds of coating agents (Production Examples ² to 4) have some solvents that do not exhibit solubility, but they are used for various solvents and monomers. The result was said to have solubility. Therefore, since the zirconium oxide nanoparticles of the present invention exhibit solubility in various organic solvents, the zirconium oxide particles can be obtained by performing a polymerization reaction after mixing with a monomer that not only widens the range of solvent selection, It has been demonstrated that homogeneously dispersed rosin can be produced.

 [0162] Production Example 5 Production of acid-zirconium nanoparticles coated with neodecanoic acid and stearic acid

Stearic acid (1.5 parts by mass) was added to the dispersion obtained by dispersing the acid-zirconium nanoparticles (10 parts by mass) obtained in Production Example 1 above in toluene (50 parts by mass), and 90 ° C. And heated at reflux for 1 hour. Add acetone (200 parts by mass) to the reaction solution, Filtered off. The obtained filtrate was concentrated under reduced pressure to obtain zirconium oxide nanoparticles. When the obtained acid-zirconium nanoparticles were analyzed by TG-DTA (thermogravimetric differential thermal analysis), there were exothermic peaks near 350 ° C and 450 ° C, so there were two types: neodecanoic acid and stearic acid. It was confirmed that it was coated with a coating agent. The total amount of neodecanoic acid and stearic acid was 24.0% by mass based on the weight loss rate. Further, the conversion coefficient obtained from the particle size distribution was 20% as in Production Example 1 above.

 [0163] Production Example 6 Production of resin composition

 The zirconium oxide nanoparticles obtained in Production Examples 1, 2 and 5 were dispersed in toluene. A cycloolefin resin (manufactured by ZEON Corporation, trade name: ZEONEX 330R) resin was added to the dispersion with the blending amounts shown in Table 2, and ultrasonic treatment was performed for 30 minutes for dissolution. The solution, a dispersion of Examples 1 to 4, was obtained. The obtained dispersion was precipitated in an equal volume mixture of methanol and distilled water to obtain a resin composition (Examples 1 to 4) in which acid-zirconium particles were dispersed in cycloolefin resin. The composition was thermoformed to produce a substrate having a thickness of 3. Omm, and a transparent substrate was obtained. When a cross-section was observed with a TEM (transmission electron microscope), it was confirmed that the zirconium oxide particles were uniformly dispersed in the resin. In addition, acid-zirconium particles that are not coated with a coating agent (manufactured by Sumitomo Osaka Cement Co., Ltd., trade name: NST-300T, average particle size: 40 nm), and acid-sodium titanium particles (made by Ishihara Sangyo Co., Ltd., trade name: Substrates were produced in the same manner using ultrafine oxide titanium oxide TTO-51 (average particle size: 18 nm).

 [0164] [Table 2]

 [0165] Test Example 4 Measurement of refractive index and Abbe number

 With respect to the resin substrate obtained in Production Example 6, the refractive index and Abbe number were measured with an Abbe refractometer (manufactured by Atago Co., Ltd., DR-M2). The results are shown in Table 3.

[0166] Test Example 5 Measurement of light transmittance The resin substrate obtained in Production Example 6 was measured according to ASTM D1003. [0167] Test Example 6 Light Resistance Test

Using the super xenon weather meter (manufactured by Suga Test Instruments Co., Ltd.), temperature: 63 ° C (BPT), humidity: 50% RH, illuminance: 180WZm ² Under these conditions, the light transmittance at a wavelength of 400 nm after 200 hours from the start of light irradiation was measured. The results are shown in Table 3. In addition, in the resin composition 5 using commercially available zirconium oxide particles, the light transmittance itself was low, so the light resistance test was not performed.

[0168] Test Example 7 Heat resistance test

 The resin substrate obtained in Production Example 6 was placed in an oven at 150 ° C., and the light transmittance at a wavelength of 400 nm after 72 hours was measured. The results are shown in Table 3. In addition, in the resin composition 5 using commercially available acid / zirconium particles, the light transmittance itself is low! Because of this, the heat resistance test did not work.

[0169] [Table 3]

 [0170] As described above, a commercially available zirconium oxide acid not coated with a coating agent was inadequate as an optical material having low light transmittance because of its poor dispersibility with respect to rosin. In addition, in the case of the resin composition 6 containing titanium oxide, it was probably due to the decomposition of the resin but it was particularly inferior in light resistance. Furthermore, in the case of the resin composition 4 containing particles coated only with one type of coating agent, the results such as light transmittance were good, but the Abbe number was not satisfactory.

[0171] In contrast, the resin compositions 1 to 3 containing the particles of the present invention coated with two or more kinds of coating agents are not only excellent in light transmittance but also have a high Abbe number. The higher the Abbe number, the smaller the chromatic aberration, the less chromatic aberration. Thus, it has been demonstrated that the resin composition according to the present invention is extremely excellent as an optical material such as a lens. [0172] Production Example 7 Production of acid-zirconium nanoparticles coated with neodecanoic acid and 2- (3,4 epoxy cyclohexyl) ethyltrimethoxysilane

 In the above Production Example 2, instead of 3-methacryloxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM 303, 1.5 g) In the same manner except that was used, acid-zirconium nanoparticles coated with neodecanoic acid and 2- (3,4 epoxy cyclohexyl) ethyltrimethoxysilane were produced.

 [0173] When the crystal structure of the obtained acid-zirconium nanoparticles was confirmed with an X-ray diffractometer, diffraction lines belonging to tetragonal and monoclinic crystal structures were detected. From the intensity of the diffraction peak, it was confirmed that the crystal structure was mainly tetragonal and slightly monoclinic. In addition, when the zirconium oxide nanoparticles were dispersed in toluene and the particle size was measured by FE-SEM, the average particle size was 5 nm.

 [0174] Further, when the nanoparticles were analyzed by an infrared absorption spectrum, absorption derived from Si—O—C was observed in addition to absorption derived from C—H and absorption derived from C OOH. These absorptions are thought to originate from neodecanoic acid and silane coupling agents that coat the zirconium oxide nanoparticles.

 [0175] Furthermore, the mass reduction rate of acid-zirconium nanoparticles was measured by TG-DTA (thermogravimetric differential thermal analysis) when the temperature was raised to 800 ° C at a rate of 10 ° CZ in an air atmosphere. The rate of decrease was 25% by mass. Therefore, it was confirmed that the neodecanoic acid and the silane coupling agent that had been coated with the acid-zirconium nanoparticles were 25% by mass of the whole particles.

[0176] Further, the conversion coefficient obtained from the particle size distribution was 20% as in the case of the particles of Production Example 1.

 [0177] Production Example 8 Production of coconut resin composition

Disperse the acid-zirconium nanoparticles obtained in Production Example 4 and Production Example 7 in toluene, add an epoxy resin hardener and the like to the dispersion in the amount shown in Table 4, and disperse uniformly. I let you. Subsequently, the rosin composition 7-12 which concerns on this invention was obtained by depressurizingly distilling toluene. The resulting composition was made from a glass plate with a 2 mm spacer in between. And heated at 100 ° C for 1 hour and 130 ° C for 2 hours to obtain a cured product having a thickness of 2 mm. For comparison, acid-zirconium nanoparticles obtained in Production Example 1 above, acid-zirconium particles not coated with a coating agent (manufactured by Sumitomo Osaka Cement Co., Ltd., trade name: NST-300T, average particle) (Diameter: 40nm) and titanium oxide particles (Ishihara Sangyo Co., Ltd., trade name: Ultra Fine Particles Titanium TTO-51, Average Particle Size: 18nm) and cured in the same amount as shown in Table 5. The thing was manufactured. In the table, Celoxide 2021P is an epoxy resin manufactured by Daicel Chemical Industries, Ltd., and its chemical name is 3,4 epoxycyclohexylmethyl-3 ′, 4 ′ epoxycyclohexenecarboxylate. Rica Resin HBE-100 is an epoxy resin manufactured by Nippon Science and Technology, and its chemical name is hydrogenated bisphenol A diglycidyl ether. Ricacid MH 700 is a curing agent manufactured by Shin Nippon Chemical Co., Ltd., and its chemical name is methylhexahydrophthalic anhydride.

[0178] [Table 4]

 [0179] [Table 5] Composition Composition Composition Composition

 1 2 1 3 1 4 1 5

 Celoxide 2021 P 100 parts by mass 100 parts by mass 100 parts by mass

 Recovery HBE—100 100 parts by mass Hardener

 RIKEN MH-700 100 parts by weight 100 parts by weight 100 parts by weight 100 parts by weight Curing accelerator

 2-Ethyl-4-

0.4 parts by weight 0.4 parts by weight 0.4 parts by weight 0.4 parts by weight

 Silconium oxide nanoparticles

 Production Example 1 200 parts by mass

Commercially available silicon oxide particles 200 parts by mass 200 parts by mass Commercially available titanium oxide particles 200 parts by mass [0180] Test Example 8

 The cured product having a thickness of 2 mm obtained in Production Example 8 was measured for light transmittance and refractive index in the same manner as in Test Examples 4 to 7, and also subjected to a light resistance test and a heat resistance test. However, in the light resistance test, the light transmittance was measured after 100 hours, 200 hours and 300 hours from the start of light irradiation. The results are shown in Table 6.

[0181] [Table 6]

[0182] As described above, the cured product composed of the resin compositions 13 and 15 containing commercially available zirconium oxide not coated with a coating agent has low dispersibility, and thus has low light transmittance. In addition, in the case of the resin composition 14 containing titanium oxide, it is probably due to the decomposition of the resin but it is particularly inferior in light resistance. Furthermore, the cured product made of the resin composition 12 containing particles coated only with one type of coating agent was relatively inferior in dispersibility, so that the results such as light transmittance were not satisfactory.

 [0183] On the other hand, the cured product composed of the resin compositions 7 to 11 containing the particles of the present invention coated with two or more kinds of coating agents was excellent in light transmittance and light resistance. Therefore, it was proved that the nanoparticle of the present invention having an acid-zirconium force is extremely excellent as an optical material or an optical semiconductor sealing material.

 [0184] Production Example 9 Production of acid zirconium nanoparticles coated with neodecanoic acid and p-styryltrimethoxysilane

In the above production example 2, P-styryltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-1403, 4 g) and water (4 g) were used instead of 3-methacryloxypropyltrimethoxysilane. Zirconium oxide nanoparticles coated with neodecanoic acid and P-styryltrimethoxysilane were prepared. [0185] When the obtained acid-zirconium nanoparticles were analyzed by X-ray structural diffraction, diffraction peaks attributed to tetragonal and monoclinic crystals were detected. From the intensity of the diffraction peak, it was confirmed that the crystal structure of the nanoparticle was mainly tetragonal and slightly monoclinic.

[0186] The nanoparticles were dispersed in toluene, and the particle size was measured by FE-SEM. The average particle size was 5 nm.

 [0187] When the nanoparticles were analyzed by infrared absorption spectrum, in addition to absorption derived from C—H and absorption derived from CO OH, absorption derived from Si—O—C was observed. Therefore, it is confirmed that the nanoparticle is covered with two kinds of coating agents, neodecanoic acid and silane coupling agent.

 [0188] The mass reduction rate of the acid-zirconium nanoparticles when the nanoparticles were heated to 800 ° C at a rate of 10 ° CZ in an air atmosphere by TG-DTA (thermogravimetric differential thermal analysis) As a result, the reduction rate was 17% by mass. Therefore, it was confirmed that the amount of the coating agent covering the zirconium oxide nanoparticles was 17% by mass of the whole particles. The conversion coefficient obtained from the particle size distribution was 20% as in Production Example 1 above.

 [0189] Production Example 10 Production of a resin composition containing nanoparticles

 In a flask equipped with a stirrer, inert gas introduction tube, reflux condenser and thermometer, polyoxyethylene styrenated phenol ether sulfate ammonium salt (Daiichi Kogyo Co., Ltd. — 08) Charged 600 parts by mass of deionized water in which 4 parts by mass was dissolved. Separately, 280 parts by mass of styrene, 120 parts by mass of dibulebenzene (manufactured by Nippon Steel Chemical Co., Ltd., D VB960), 8 parts by mass of dilauroyl peroxide (manufactured by NOF Corporation, Parolyl L), and Production Example 1 270 parts by mass of the nanoparticles obtained in Example 2 or Production Example 9 were charged into a beaker and subjected to electromagnetic stirring for 30 minutes to prepare a uniform and transparent solution. The obtained solution was put into a flask to which an aqueous emulsifier solution had been previously added, and stirred at 6000 rpm for 5 minutes with a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to obtain a uniform suspension.

[0190] While nitrogen gas was blown into the suspension, the mixture was heated to 75 ° C and stirred for 1.5 hours to carry out a suspension polymerization reaction. Furthermore, the temperature was raised to 85 ° C and the mixture was aged for 2.5 hours, and as a result, a suspension containing rosin particles was obtained. The 50% cumulative diameter and standard deviation of the fat particles contained in the suspension are It was measured with one multisizer (manufactured by Beckman Coulter).

 [0191] The obtained rosin suspension was filtered off with a suction filter to obtain a cake with resin particle strength.

 The cake was dried under reduced pressure at 80 ° C. for 12 hours to obtain a block-like product having rosin particle strength. The block-like product was crushed using a lab jet mill (manufactured by Enomoto Pneumatic Kogyo Co., Ltd.) to obtain rosin particles. For comparison, similar resin particles were obtained without using nanoparticles. The obtained resin particles were observed with a transmission electron microscope (TEM). Further, the refractive index of the resin particles was measured in the same manner as in Test Example 4. Table 7 shows the results.

 [0192] [Table 7]

 [0193] As shown in the above results, the resin particles containing acid-zirconium nanoparticles coated only with neodecanoic acid are not uniformly dispersed, and the agglomerated particles are not uniformly dispersed. It did not have transparency and was unable to even measure the refractive index.

 [0194] On the other hand, the resin particles containing the zirconium oxide nanoparticles according to the present invention have high transparency because the zirconium oxide nanoparticles are uniformly dispersed. In addition, it does not contain zirconium oxide nanoparticles and has a higher refractive index than that of resin particles, so it is extremely useful as an optical material.

[0195] Production Example 11 Production of light diffusion film

It was manufactured in Production Example 10 in a binder resin composition containing 100 parts by weight of polyester polyol, 20 parts by weight of polyfunctional isocyanate (Sumijoule N3200, manufactured by Sumika Bayer Urethane Co., Ltd.), and 2 parts by weight of antistatic agent 3 A coating composition was prepared by mixing 50 parts by mass of seed resin particles. The coating composition was applied to the surface of a transparent biaxially stretched polyester film having a thickness of 100 m by a roll coating method. The coated film was allowed to stand at room temperature for 1 hour and then dried at 80 ° C. for 2 hours to produce a light diffusion film having a thickness of 15 m. [0196] For each of the obtained light diffusion films, the total light transmittance and haze value were measured using a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., NDH-1001 DP). In addition, each light diffusion film was placed on the upper surface of a light guide plate type backlight device, and the luminance was measured using a luminance meter (manufactured by TOPCON, BM-7). The results are shown in Table 8.

 [0197] [Table 8]

[0198] As described above, the light diffusing film comprising the oxyzirconium nanoparticles of the present invention as a constituent compared to the light diffusing film comprising the acid zirconium nanoparticles coated only with neodecanoic acid as a constituent. Was demonstrated to have high light transmittance and brightness.

 [0199] Production Example 12 Production of light diffusion plate

 Polycarbonate resin (Mitsubishi Engineering Plastics Co., Ltd., Iupilon E2000FN) 100 parts by mass, three kinds of resin particles produced in Production Example 10 0.5 parts by mass, antioxidant (manufactured by Ciba Specialty Chemicals Inc., Ilganox 2215 , Phenolic 'Phosphate' Lataton 3 types) 0.05 parts by mass, and optical brightener (Tinoku Specialty Chemicals, Ubitex OB, oxazole series) 0.003 parts by mass, vent It was supplied to a sheet extrusion molding machine equipped with a gear pump, 3 rolls and 2 necks. Next, sheet molding was performed at a molding temperature of 280 ° C. to produce a light diffusion plate having a thickness of 2 mm.

[0200] The obtained light diffusion plate was cut into a rectangular shape having a length of 23 lmm and a width of 321 mm. This light diffusing plate was incorporated into a direct backlight unit for a 15-inch liquid crystal display device. The intensity of the cold cathode tube lamp of the backlight unit was adjusted to 10, OOOcdZm ^2, and the luminance at the center point of the measurement sample was measured using a luminance meter (manufactured by TOPCON, BM-7). The results are shown in Table 9.

[0201] [Table 9] Nanoparticle Coating Luminance (cd / m ² )

 Ne 亍 "Kan fe +

 Production Example 2 3800

 3-methacryloxyb pill trimethoxysilane

 Neo 亍 'canic acid +

 Production Example 9 3820

 P-styryltrimethoxysilane

 Production Example 1 Neo 亍 'canic acid 3260

[0202] As described above, the light diffusion plate containing zirconium oxide nanoparticles of the present invention has higher luminance than the light diffusion plate containing zirconium oxide nanoparticles coated only with neodecanoic acid. It was proved.

 [0203] Production Example 13 Production of antiglare film

3 parts by mass of each resin composition obtained in Production Example 10 and 20 parts by mass of toluene were sufficiently mixed by stirring. 40 parts by mass of acrylic ionizing radiation-cured resin, 2 parts by mass of a photopolymerization initiator (manufactured by Ciba Specialty Chemicals Inc., Irgacure 907), 23 parts by mass of methyl ethyl ketone, 2 parts by mass of ethylene glycol monobutyl ether And a leveling agent (BYK320, manufactured by Bitta Chemie) were added and sufficiently stirred to prepare a coating solution. The coating solution was applied to one side of a 80 / zm-thick triacetyl cellulose film (Fuji Photo Film Co., Ltd., Fujitac) with a bar coater. The coated film was dried with an 80 ° C. tray, and then an anti-glare film was produced by irradiating 300 mjZcm ² of ultraviolet rays using a high-pressure mercury lamp to cure the resin component.

[0204] A black film was pasted on the back of each antiglare film, a lOOOOcdZm ² fluorescent lamp was projected from a distance of 2 m, and the degree of blur of the reflected image was evaluated according to the following criteria.

 ○: The outline of the fluorescent lamp cannot be distinguished.

 X: The outline of the fluorescent lamp can be clearly identified

 [0205] For each antiglare film, a mapping measuring device (ICB-1DD, manufactured by Suga Test Instruments Co., Ltd.) and 0.

 Using a 5 mm wide optical comb, the transmission clarity was measured according to JIS K7150.

[0206] In addition, each anti-glare film is connected to a personal computer LCD monitor (15-inch XGA, TFT-TN system, front brightness: 350 cd / m ² , front contrast: 300 to 1, surface AG: none) It was bonded to the surface, and the character blur was evaluated according to the following criteria. The results are shown in Table 10.

○: The outline of the character is completely blurred. X: The outline of the character is blurred and a strong sense of incongruity is felt

[0207] [Table 10]

 [0208] As described above, the antiglare film containing zirconium oxide nanoparticles coated only with neodecanoic acid is excellent in antiglare properties but has low transparency due to poor dispersibility of the nanoparticles. It was a character blur. On the other hand, the light diffusing film containing acid-zirconium nanoparticle of the present invention was excellent in antiglare property and transparency, and did not cause character blurring. Therefore, it was demonstrated that the antiglare film according to the present invention is very practical.

 [0209] Production Example 14 Production of zirconium oxide nanoparticles coated with neodecanoic acid and synthetic silane coupling agent

 [0210] (1) Synthesis of Silane Coupling Agent (Surface Coating Agent A)

 Before starting the synthesis, a methacryloyl-group-terminated polydimethylsiloxane having a weight average molecular weight of about 5000 (Chisso, Silaplane FM-0721, 160 g), cyclohexenoremethacrylate (34 g) and 3-methacryloxypropyltrimethoxysilane ( Shin-Etsu Chemical Co., Ltd. KBM-503, 6 g) was mixed. Hereinafter, the mixture is referred to as a mixture A. Dimethyl-2,2, -azobis (2-methylpropionate) (Wako Pure Chemical Industries, V-601, 13.2 g) was mixed with toluene (49 g). Hereinafter, the mixture is referred to as a mixture B. Furthermore, n-dodecyl mercabtan (12 g) and toluene (40 g) were mixed. Hereinafter, the mixture is referred to as mixture C.

[0211] A 500 mL four-necked flask equipped with a stirrer, thermometer, dripping device, cooling tube and nitrogen blowing tube was charged with butanol (31.2 g) and toluene (100.4 g). Replaced with nitrogen. The solvent was heated with stirring and when refluxed, the entire amount of mixture A, 52 g of mixture B, and the entire amount of mixture C were added dropwise over 2 hours. After the start of dripping The reaction temperature was maintained at 110 ° C, and the remaining mixture B was added in three portions every hour after the completion of the dropwise addition. After charging the entire amount of the mixture B, the mixture was stirred at 110 ° C. for 2 hours. Next, the reaction mixture was cooled to room temperature, and a viscous and colorless and transparent silane coupling agent was obtained. The silane coupling agent is referred to as “surface coating agent A”.

 [0212] (2) Substitution reaction

 In an lOOmL 4-fluoro flask equipped with a stirrer, thermometer, cooling tube and nitrogen blowing tube, hexane (43 g), acid-zirconium nanoparticles obtained in Production Example 1 (4.1 lg) and The above surface coating agent A (2.87 g) was charged. The reaction mixture was stirred at reflux for 8 hours. Subsequently, the reaction mixture was cooled, and the precipitate was filtered off to obtain acid-zirconium nanoparticles (4.31 g) coated with neodecanoic acid and surface coating agent A.

 [0213] (3) Dispersibility test

 When the zirconium oxide nanoparticles (4 g) obtained above were mixed with epoxy group side chain polydimethylsiloxane (manufactured by Toray Dow Coung Co., SF8411, 5.34 g), it was highly viscous and fluid and colorless and transparent. A composition was obtained. Therefore, it was found that the above-mentioned zirconium oxide nanoparticles have high dispersibility.

 [0214] Production Example 15 Manufacture of a resin composition

Fully dehydrated neopentyldaricol (hereinafter abbreviated as “NPG”) (1 35 g), a flask equipped with a stirrer, thermometer, condenser, and air / nitrogen mixed gas inlet tube. Methyl methacrylate (also abbreviated as “MMA”) (400 g), potassium t-butoxide (hereinafter abbreviated as “t-BuOK”) (1.35 g) and 4 hydroxy-1,2, 2,6,6-tetramethylpiperidine Noxyl (hereinafter sometimes abbreviated as “4H-TEMPO”) (13.5 mg) was added. The reaction mixture was stirred at 110 ° C. for 4 hours, and transesterification was performed while distilling off only the methanol produced by the reaction. The reaction solution obtained After distilling off the unreacted MMA, the unreacted neopentyl glycol, neopentyldarlicol monometatalylate and the catalyst were removed by washing with water, whereby the dimethacrylic acid ester of neopentyldalycol was removed. Got. When the content of sulfur atoms contained in the dimethacrylate is analyzed by inductively coupled plasma analysis (hereinafter abbreviated as “ICP”), no sulfur atoms are observed. It was.

[0215] The obtained dimethacrylic acid ester, the acid-zirconium nanoparticles obtained in Production Example 4, and 2-hydroxy-2-methyl-1-phenolpropane 1-one (Ciba Special) Taro Chemicals Darocur 1173) was mixed in the proportions shown in Table 11. In addition, the value in a table | surface shows a mass part. Separately, a lmm-thick silicon rubber spacer was placed on a glass plate, and the above mixture was poured into a portion surrounded by the spacer. A 250 μm thick PET film is placed on top of it, and a 250 mW ultra high pressure mercury lamp is used to radiate UV light at a wavelength of 365 nm and an irradiation intensity of 43¾ [/ «11 ² 'seconds for 93.2 seconds. Then, a sheet-like molded body was obtained by effecting rosin.

 [0216] [Table 11]

[0217] Production Example 16 Production of coconut resin composition

 Addition of neopentyldarlicol ethylene oxide 4 mol adduct (hereinafter abbreviated as “NPG-4 EO”) to a flask with a stirrer, thermometer, condenser, and air / nitrogen mixed gas inlet tube (311 g), MMA (400 g), dibutyltinoxide (hereinafter abbreviated as “DBTO”) (6.22 g) and 4H—TEMPO (31. lmg) were added. The reaction mixture was stirred at 110 ° C. for 6 hours, and transesterification was carried out while distilling off only the methanol produced by the reaction. By distilling off unreacted MMA from the obtained reaction solution, dimethacrylic acid ester obtained by adding ethylene oxide to neopentyl glycol was obtained. When the content of sulfur atoms contained in the dimethacrylic acid ester was analyzed by ICP, no sulfur atoms were observed.

 [0218] From the dimethacrylic acid ester, the oxyzirconium nanoparticles obtained in Production Example 4, and the photopolymerization cleavant, a sheet-like molded product having the composition shown in Table 12 was obtained in the same manner as in Production Example 15. It was.

[0219] [Table 12] No. 3 No. 4

 Methacrylic acid ester 90 70

 Nanoparticles from Production Example 4 10 30

 Photopolymerization initiator 0.2 0.2

[0220] Production Example 17 Manufacture of a resin composition

 NPG—4EO (311 g), MAA (189 g), p—toluenesulfonic acid (hereinafter abbreviated as “PTS”) is added to a flask equipped with a stirrer, thermometer, condenser, and air and nitrogen mixed gas. (10 g), toluene (50 g) and 4H—TEMPO (31. lmg) were added. The reaction mixture was stirred at 110 ° C. for 6 hours, and dehydrated ester reaction was carried out while distilling off water produced by the reaction. After completion of the reaction, washing with water, standing, and separation of the aqueous layer were repeated three times, and toluene and unreacted MAA were distilled off to distill off neopentyl glycol with ethylene oxide and dimethacrylic acid ester Got. The content of sulfur atoms contained in the dimethacrylic acid ester was analyzed by ICP. As a result, the sulfur atom content was 340 ppm.

[0221] The obtained dimethacrylic acid ester was dissolved in toluene, and water was added for liquid separation to extract sulfonic acid and sulfonate. The aqueous layer containing sulfonic acid and sulfonate was separated and concentrated under reduced pressure using an evaporator. Furthermore, after completely removing water in a hot air dryer, it was redissolved in acetone and the amount of sulfonic acid was determined by gas chromatography. Next, water was added again to the toluene layer containing dimethacrylic acid ester, and the sulfonic acid ester was hydrolyzed to sulfonic acid by heating and stirring at 100 ° C. for 10 hours. The aqueous layer was separated with a separatory funnel and concentrated under reduced pressure with an evaporator. Furthermore, after completely removing water in a hot air dryer, it was redissolved in acetone and the amount of sulfonate ester was determined by gas chromatography. The sulfur content derived from the sulfonic acid and sulfonic acid ester contained in the dimetatalic acid ester was measured from the total amount of sulfonic acid and sulfonic acid ester determined previously, and was found to be 340 ppm in terms of sulfur atom. Therefore, it was found that sulfonic acid and the like could be completely removed from dimethacrylic acid ester.

[0222] From the dimethacrylic acid ester, the zirconium oxide nanoparticles obtained in Production Example 4, and the photopolymerization cleavant, a sheet-like molded product having the composition shown in Table 13 was obtained in the same manner as in Production Example 15. (In Table 13, No. 5 and No. 6). For comparison, a sheet-like molded product (No. 7 to No. 9 in Table 13) containing only the polymerized dimethacrylate of Production Examples 15 to 17 and not containing the zirconium oxide particles of the present invention was used. , A sheet-like molded product containing a polymer of dimethacrylic acid ester of Production Example 15 and commercially available acid Zircoyu particles (Nissan Chemical Co., Ltd., Zircoyusol ZR-40BL) not coated with a coating agent (in Table 13, No. 10) was prepared similarly.

 13]

[0224] Test Example 9 Measurement of refractive index, light transmittance and light resistance

 With respect to the sheet-like molded products No. 1 to 10 obtained in Production Examples 15 to 17 described above, the refractive index and the light transmittance were measured, and a light resistance test was further performed.

 [0225] The refractive index of each sheet-like molded product was measured as a refractive index of D line (wavelength: 589 nm) at a temperature of 20 ° C using a refractometer (manufactured by Atago Co., Ltd., DR-M2).

 [0226] The light transmittance was measured in a transmission mode using a -1 meter (Nippon Denshoku Co., Ltd., Sigma 90 system).

[0227] The weather resistance was evaluated as follows. First, the color tone of each sheet-like molded product was measured in a transmission mode using a color difference meter (manufactured by Nippon Denshoku Co., Ltd., Sigma 90 system). Next, using a super energy energy irradiation tester (made by Suga Test Instruments Co., Ltd.), each sheet-like molded product was subjected to light of temperature: 60 ° C, humidity: 70% Rh, wavelength: 295 to 450 nm. Irradiation intensity: 100 mW / cm ² for 6 hours, followed by 10 cycles (total: 120 hours) of a set of 6 hours of dew condensation in an environment of 30 ° C and humidity: 90% Rh . Next, the color tone of each sheet-like molded product after the treatment was measured in the same manner as described above. The weather resistance is represented by a yellow index change rate (ΔΥΙ) before and after the above treatment. The discoloration due to the above treatment is almost equivalent to the discoloration in the actual outdoor exposure test over 2.5 years. Table 14 shows the results. [0228] [Table 14]

[0229] As described above, the resin composition (No. 10) containing commercially available acid-zirconium particles that are not coated with a coating agent has poor particle dispersibility and aggregates in the resin. Refractive index and light resistance with low light transmittance were not able to be measured. In addition, the resin compositions (No. 7 to No. 9) that do not contain acid-zirconium particles have a problem that the light transmittance is high but the refractive index is relatively low, and the light resistance is particularly poor.

 [0230] On the other hand, in the case of the resin composition containing the zirconium oxide nanoparticles of the present invention (No. 1 to No. 6), the light transmittance is sufficiently high due to the high dispersibility of the particles.匕 Refractive index is also increased by zirconium nanoparticles. In addition, the light resistance is also significantly improved. Therefore, it was proved that the rosin composition according to the present invention is useful and highly practical.

 [0231] Production Example 18 Production of acid-zirconium nanoparticles coated with neodecanoic acid and phenol trimethoxysilane

 A solution was prepared by dispersing the zirconium oxide nanoparticles (12.3 g) obtained in Production Example 1 in toluene (8 to 7 g). To the solution, phenoltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-103, 4 g) and ultrapure water (4 g) were added and heated to reflux at 90 ° C. for 1 hour. Next, the solution was allowed to cool, and then the solution was clouded by adding n-hexane to aggregate the particles. Next, the aggregated particles were separated by filtration, and the resulting filtrate was dried under reduced pressure at room temperature to obtain acid-zirconium nanoparticle coated with neodecanoic acid and phenyltrimethoxysilane.

[0232] When the crystal structure of the obtained nanoparticles was confirmed with an X-ray diffractometer, diffraction lines belonging to tetragonal and monoclinic crystal structures were detected. From the intensity of the diffraction lines, it was confirmed that the crystal structure was mainly tetragonal and slightly monoclinic. In addition, when the particle size of the zirconium oxide nanoparticles was measured by FE-SEM, the average particle size was 5 nm. Furthermore, when analyzed by infrared absorption spectrum, absorption derived from Si—O—C was observed in addition to absorption derived from C—H and absorption derived from C OOH. These absorptions are thought to be attributed to neodecanoic acid and phenol trimethoxysilane coated with zirconium oxide nanoparticles. In addition, the mass reduction rate of zirconium oxide nanoparticles when the temperature was raised to 800 ° C at a rate of 10 ° CZ in an air atmosphere by TG-DTA (thermogravimetric differential thermal analysis) % Decrease rate. Therefore, it was confirmed that neodecanoic acid and phenol trimethoxysilane, which were coated with the zirconium oxide nanoparticles, accounted for 17% by mass of the total particles. Further, the conversion factor for which the particle size distribution force was also obtained was 20%, as in the case of the particles of Production Example 1.

 [0233] Production Example 19 Production of epoxy resin composition

 Zirconium oxide nanoparticles (3. Og) coated only with neodecanoic acid in Production Example 1 were dispersed in toluene (15. Og). Next, bisphenol A (Japan Epoxy Resin Co., Ltd., JER828EL, epoxy equivalent: 184 to 194, 7. Og) was mixed and mixed until uniform, and then concentrated under reduced pressure at 90 ° C. A fat composition was obtained.

 [0234] Further, instead of the nanoparticles in Production Example 1, the nanoparticles (2. Og) and toluene (15.

 Similarly, an epoxy resin composition was obtained using Og).

 [0235] To each of the epoxy resin compositions described above, a cationic polymerization initiator (manufactured by Sanshin Chemical Industry Co., Ltd., Sun-Aid SI-80L) was added at 50 ° C or less so as to be 1% by mass with respect to the total amount. did. The mixture was mixed until uniform and then defoamed under reduced pressure. The defoamed mixture was applied on a 150 mm X 70 mm X 2 mm glass plate with an lOmil (254 μm) applicator. When bubbles were generated due to the presence of the solvent, a film was obtained by curing at 150 ° C. for 3 hours while performing a vacuum treatment. The appearance of the obtained film was visually confirmed. The results are shown in Table 15. The values in Table 15 indicate parts by mass.

[0236] [Table 15]

[0237] As shown above, the nanoparticles of Production Example 1 coated only with neodecanoic acid are dispersed. Since the properties were not sufficient, the obtained film-shaped rosin composition was cloudy. On the other hand, since the particles of the present invention, which are coated with a silane coupling agent together with neodecanoic acid, are excellent in dispersibility, the obtained film-like resin composition was transparent.

Claims

The scope of the claims  [1] covered with two or more coatings;  Metal oxide nanoparticles, wherein at least one of the coating agents is represented by the following formula (I): R ¹ -COOH (1) [Wherein R ¹ represents a hydrocarbon group having 6 or more carbon atoms. ] 2. The metal oxide nanoparticles according to claim 1, wherein the metal oxide is zirconium oxide. [3] The metal oxide nanoparticles according to claim 2, comprising tetragonal acid-zirconium as the acid-zirconium. [4] The metal oxide nanoparticles according to any one of [ ¹ ] to [3], wherein R ¹ represents a branched hydrocarbon group having 6 or more carbon atoms. [5] At least one coating agent other than the coating agent represented by formula (I) is selected from the group consisting of a hydroxyl group, an amino group, a thiol group, a carboxyl group, an epoxy group, and an alkoxy group. 5. The metal oxide nanoparticles according to claim 1, wherein the metal oxide nanoparticles have a plurality of one kind of functional group.  6. The metal oxide nanoparticles according to any one of claims 1 to 5, wherein at least one coating agent other than the coating agent represented by the formula (I) has a vinyl group or a phenyl group. . 7. The metal oxide nanoparticles according to any one of claims 1 to 6, wherein at least one coating agent other than the coating agent represented by formula (I) is a silane coupling agent. 8. The metal oxide nanoparticles according to claim 4, wherein at least one coating agent other than the coating agent represented by formula (I) is represented by the following formula (II). R ² -COOH ( ² ) [Wherein R ² represents a linear hydrocarbon group having 6 or more carbon atoms. ] [9] A step of preparing a coating agent (I) metal composite from at least a metal oxide precursor and a coating agent represented by the following formula (I): R ¹ -COOH (1) [Wherein R ¹ represents a hydrocarbon group having 6 or more carbon atoms. ] By mixing water with the above coating agent (I) metal composite, it is hydrothermally reacted below IMPaG. Obtaining metal oxide nanoparticles coated with a coating agent (I); and  Coating the metal oxide nanoparticles with two or more coating agents by allowing a coating agent other than the coating agent (I) to act on the obtained metal oxide nanoparticles;  A method for producing metal oxide nanoparticles, comprising: [10] A metal oxide nanoparticle-containing composition comprising the metal oxide nanoparticles according to any one of claims 1 to 8.  [11] Metal oxide nanoparticle force according to any one of claims 1 to 8, dispersed in one or more selected from the group consisting of solvent, monomer, polymer, plasticizer force Metal oxide nanoparticle dispersion.  [12] A coating composition containing the metal oxide nanoparticles according to any one of claims 1 to 8.  [13] A resin composition comprising the metal oxide nanoparticles according to any one of claims 1 to 8.  [14] A film containing the metal oxide nanoparticles according to any one of [1] to [8].  [15] An optical material comprising the metal oxide nanoparticles according to any one of claims 1 to 8.  [16] An optical semiconductor encapsulant containing the metal oxide nanoparticles according to any one of claims 1 to 8.