Metal oxide particles with coating and varnish using same

Abstract

Provided are: a metal oxide particle (C) with a high coverage in which the surface of a metal oxide particle (A) containing titanium oxide serving as a nucleus is coated with a coating (B), wherein the coverage of the particle (C) in which the particle (A) is coated with the coating (B) is 50%-100%; and a method for measuring the coverage using an electrochemical method.　The metal oxide particle (A) serving as a nucleus is a titanium oxide single oxide particle (A1) or a metal oxide particle (A2) which includes titanium oxide and is further combined with at least one metal oxide selected from the group consisting of tin oxide, zirconium oxide, silicon dioxide, zinc oxide, antimony oxide, niobium oxide, iron oxide, and tungsten oxide. The coating (B) is at least one coating (B) selected from the group consisting of electrochemically inert metal oxide particles (B1), an amine (B2), a silane coupling agent (B3), and an organic acid and an organic acid ester (B4).

Description

Metal oxide particles containing coatings and varnishes using them

[0001] The present invention relates to metal oxide particles containing a coating, a varnish using the same, and a method for measuring the coverage area of ​​a coating on the surface of metal oxide particles.

[0002] Plastic molded products are used in large quantities due to their advantages such as light weight, easy processability, and impact resistance, but on the other hand, they have practical drawbacks for use as eyeglass lenses, window materials, etc., such as insufficient hardness, susceptibility to scratches, susceptibility to solvent attack, electrostatic charge and dust attraction, and insufficient heat resistance. Therefore, it has been proposed to apply a protective coating to plastic molded products. A large number of types of coating solutions for forming the protective coating have been proposed.

[0003] A coating solution for forming a film, whose main component (resin component or film-forming component) is an organosilicon compound or its hydrolyzate, is used for forming a hard film similar to that of an inorganic system for eyeglass lenses (see Patent Document 1).

[0004] Since the abrasion resistance of the above-mentioned coating solution for forming a film is still unsatisfactory, a solution containing a colloidally dispersed silicon dioxide sol has been proposed and has been put to practical use for eyeglass lenses (see Patent Document 2).

[0005] Incidentally, most conventional plastic eyeglass lenses have been manufactured by cast polymerization of diethylene glycol bisallyl carbonate monomer. This lens has a refractive index of approximately 1.50, which is lower than the refractive index of glass lenses, approximately 1.52, and therefore has the disadvantage that the rim thickness of lenses for myopia is thick. For this reason, in recent years, development has been underway to develop monomers with refractive indices higher than diethylene glycol bisallyl carbonate, and high-refractive-index resin materials with refractive indices ranging from 1.54 to 1.76 have been proposed (see Patent Documents 3 and 4).

[0006] For such high refractive index resin lenses, a method has been proposed in which a colloidal dispersion of metal oxide fine particles of Sb or Ti is used as a coating material (see Patent Documents 5 and 6).

[0007] Patent Document 7 discloses a coating composition comprising a silane coupling agent and a stable modified metal oxide sol having a primary particle size of 2 to 100 nm, the coating comprising particles (c) obtained by coating the surfaces of metal oxide colloidal particles (a) having a primary particle size of 2 to 60 nm with a coating (b) consisting of colloidal particles of an acidic oxide, the coating comprising (c) being present in an amount of 2 to 50 mass % calculated as metal oxide. Specific examples of colloidal particles used include a modified titanium oxide-zirconium oxide-stannic oxide composite colloid coated with alkylamine-containing antimony pentoxide. Patent Document 8 discloses a titanium oxide-stannic oxide-zirconium oxide composite colloid stabilized with an alkylamine or an oxycarboxylic acid.

[0008] JP-A-52-11261 JP-A-53-111336 JP-A-55-13747 JP-A-64-54021 1986-151801 JP 63-275682 JP 2001-123115 JP 10-306258

[0009] However, there are no prior art documents disclosing the surface coverage of surface-coated particles in which the surfaces of titanium oxide-containing particles are coated with a coating agent. Although attempts have been made to determine the coverage from the ratio of added coating agent to free coating agent, the actual coverage remains unknown. In particular, when the particle diameter is several tens of nanometers, it is difficult to completely separate the particles from the dispersion medium, making it difficult to determine the coverage. In view of the limitations of the above-mentioned prior art, an object of the present invention is to provide core-shell metal oxide particles (C) in which the surfaces of titanium oxide-containing metal oxide particles (A) as cores are coated with a coating material (B) as shells, thereby providing metal oxide particles (C) with a high coverage of 50 to 100%.

[0010] In a first aspect, the present invention provides coated metal oxide particles (C) in which the surfaces of titanium oxide-containing metal oxide particles (A) serving as cores are coated with a coating material (B), the particles (C) having a coverage of 50 to 100% as measured by the following measurement method: An electrode-forming composition comprising a binder, conductive carbon, and the metal oxide particles (C), the composition containing 85 mass % of the metal oxide particles (C), is applied to a copper foil in a thickness of 200 μm, dried, and then removed as a film having an area of ​​13 mmφ to serve as a positive electrode; a lithium foil having an area of ​​13 mmφ is used as a negative electrode; these are combined to prepare an electrochemical cell; and the cell is subjected to three cycles of charge and discharge in the range of 1.4 to 3.0 V, and the average charge capacity (mAh / g) for the three cycles is measured.(Coating rate of metal oxide particles (C) obtained by coating core metal oxide particles (A) with coating material (B)%)=100−[[(average value (mAh / g) of charge capacities of each sample over three charge / discharge cycles according to the above measurement method) / (theoretical charge capacity of titanium oxide particles (mAh / g))]×100], where the theoretical charge capacity of titanium oxide is 120 (mAh / g); as a second aspect, metal oxide particles (C) according to the first aspect, in which the coating rate is 90 to 100%; as a third aspect, metal oxide particles (C) according to the first aspect, in which the content of titanium oxide in the total metal oxide is 50 mol % or more; As a fourth aspect, the metal oxide particles (C) according to any one of the first to third aspects, in which the core metal oxide particles (A) are titanium oxide single oxide particles (A1), or metal oxide particles (A2) containing titanium oxide and a combination of at least one metal oxide selected from the group consisting of tin oxide, zirconium oxide, silicon dioxide, zinc oxide, antimony oxide, niobium oxide, iron oxide, and tungsten oxide; as a fifth aspect, the metal oxide particles (C) according to any one of the first to fourth aspects, in which the coating (B) is at least one coating (B) selected from the group consisting of electrochemically inactive metal oxide particles (B1), amines (B2), silane coupling agents (B3), and organic acids and organic acid esters (B4); as a sixth aspect, the metal oxide particles (C) according to the fifth aspect, in which the electrochemically inactive metal oxide particles (B1) are metal oxides (B1) that are electrochemically inactive in a range of 1.4 to 3.0 V in a test of repeated charge and discharge in an electrochemical cell; As a seventh aspect, the metal oxide particles (C) according to the fifth aspect, in which the electrochemically inactive metal oxide particles (B1) are metal oxides (B1) consisting of a combination of at least one metal oxide selected from the group consisting of tin oxide, zirconium oxide, silicon dioxide, zinc oxide, antimony oxide, niobium oxide, iron oxide, and tungsten oxide; as an eighth aspect, the metal oxide particles (C) according to the fifth aspect, in which the amine (B2) is a secondary amine or a tertiary amine having a total number of carbon atoms of 5 to 35; and as a ninth aspect, the silane coupling agent (B3) is

[0011]

[0012] (In formula (1), R １ are each an alkyl group, a halogenated alkyl group, an alkenyl group, an aryl group, or an organic group having a polyether group, an epoxy group, a (meth)acryloyl group, a mercapto group, an amino group, a ureido group, an acid anhydride group, or a cyano group, and are bonded to a silicon atom by a Si—C bond, and R ２ represents an alkoxy group, an acyloxy group, or a halogen group, and a represents an integer of 1 to 3. In formulas (2) and (3), R ３ and R ５ are each an alkyl group having 1 to 3 carbon atoms or an aryl group having 6 to 30 carbon atoms and bonded to a silicon atom by a Si—C bond, and R ４ and R ６ each represent an alkoxy group, an acyloxy group, or a halogen group, Y represents an alkylene group, an NH group, or an oxygen atom, b is an integer of 1 to 3, c is an integer of 0 or 1, and d is an integer of 1 to 3.) As a tenth aspect, the metal oxide particles (C) according to the fifth aspect, wherein the organic acid and organic acid ester (B4) are acetic acid, benzoic acid, or an alkyl, aryl, or arylalkyl ester thereof. As an eleventh aspect, the metal oxide particles (C) are prepared by irradiating a sample of the metal oxide particles (C) with ultraviolet light having a wavelength of 365 nm at an intensity of 0.4 mW / cm, the sample being prepared by mixing a dispersion of water and methanol in a mass ratio of 1:1, the dispersion containing the dispersion at a solid content of 0.5 mass %, and a 0.02 mass % dye (sunset yellow) solution in glycerin in a mass ratio of 1:3. ２the metal oxide particles (C) according to any one of the first to tenth aspects, in which a rate of fading change of the dye in a sample subjected to irradiation with 1000 kJ / cm 3 for 180 minutes is 20% or less; as a twelfth aspect, a metal oxide sol containing the metal oxide particles (C) according to any one of the first to eleventh aspects; as a thirteenth aspect, a metal oxide sol according to the twelfth aspect, in which a dispersion medium of the metal oxide sol is water, an alcohol, an ester, a ketone, an amide, or a hydrocarbon; as a fourteenth aspect, a varnish containing the metal oxide particles (C) according to any one of the first to thirteenth aspects or a sol thereof, and a thermosetting or photosetting resin; as a fifteenth aspect, a varnish according to the fourteenth aspect, in which the varnish is a varnish for improving light resistance; and as a sixteenth aspect, a varnish according to the fourteenth aspect, in which the varnish is a coating agent for eyeglass lenses. As a seventeenth aspect, there is provided a method for measuring a coverage of metal oxide particles (C) according to any one of the first to eleventh aspects, in which the surfaces of metal oxide particles (A) containing titanium oxide as cores are coated with a coating material (B), and the coverage of particles (C) obtained by coating the particles (A) with the coating material (B) is determined as a coverage according to the following measurement method: In the measurement method, an electrode-forming composition comprising a binder, conductive carbon, and the metal oxide particles (C), and containing 85 mass % of the metal oxide particles (C), is applied to a copper foil in a film thickness of 200 μm, dried, and then removed as a film with an area of ​​13 mmφ, which is used as a positive electrode, and a lithium foil with an area of ​​13 mmφ is used as a negative electrode, which are combined to prepare an electrochemical cell, and three cycles of charge and discharge are repeated in the range of 1.4 to 3.0 V, and the average charge capacity (mAh / g) is measured.(coverage rate of metal oxide particles (C) obtained by coating core metal oxide particles (A) with coating material (B)%) = 100 - [[(average value (mAh / g) of charge capacities of three charge / discharge cycles of each sample according to the above measurement method) / (theoretical charge capacity of titanium oxide particles (mAh / g))] × 100], where the theoretical charge capacity of titanium oxide is 120 (mAh / g); and as an eighteenth aspect, the method for producing metal oxide particles (C) according to any one of the first to eleventh aspects, characterized in that, in metal oxide particles (C) obtained by coating the surface of metal oxide particles (A) containing titanium oxide as cores with a coating material (B), the coverage rate of particles (C) obtained by coating the particles (A) with the coating material (B) is adjusted to 50 to 100% by the following measurement method; The measurement method involves applying an electrode-forming composition comprising a binder, conductive carbon, and metal oxide particles (C), with the metal oxide particles (C) comprising 85% by mass, to a thickness of 200 μm onto copper foil, drying, and then extracting a 13 mmφ film as the positive electrode and a 13 mmφ lithium foil as the negative electrode. These are combined to prepare an electrochemical cell, which is then charged and discharged three times in the range of 1.4 to 3.0 V to measure the average charge capacity (mAh / g). (Coverage rate of metal oxide particles (C) in which core metal oxide particles (A) are coated with coating material (B) %) = 100 - [(average charge capacity (mAh / g) of three charge / discharge cycles for each sample according to the above measurement method) / (theoretical charge capacity of titanium oxide particles (mAh / g))] × 100], where the theoretical charge capacity of titanium oxide is 120 (mAh / g).

[0013] When titanium oxide absorbs ultraviolet light, electrons are excited from the valence band to the conduction band, causing a reduction reaction, and holes generated in the valence band cause an oxidation reaction on the surface. When moisture is present in the air, oxygen is reduced to form oxide ions (O ２ － ), hydroxide ions (OH － ) is reduced to produce active oxygen species such as hydroxyl radicals. Oxidizing agents such as hydrogen peroxide may also be produced. These chemical species have the ability to oxidize and decompose organic compounds, and are effective in decomposing and removing organic compounds, cleaning water, and sterilizing.

[0014] On the other hand, when used as a coating agent on the surface of a substrate, problems such as discoloration due to decomposition of the substrate or coating layer occur.

[0015] As a method for preventing these problems, a method of inactivating the surface of particles containing titanium oxide by covering them with a coating agent has been investigated.

[0016] However, there are no documents that describe the surface coverage of surface-coated particles in which the surface of titanium oxide-containing particles is coated with a coating agent. Although there are documents that describe the loading ratio of titanium oxide-containing particles and the coating agent, the coating ratio of the coated particles, i.e., the coating ratio, is unknown. It has also been considered to determine the coverage ratio from the ratio of added coating agent to free coating agent, but when the particle diameter is several tens of nanometers, it is difficult to completely separate the particles from the dispersion medium, and the coverage ratio is unknown.

[0017] On the other hand, in metal oxide particles (C) obtained by coating the surface of metal oxide particles (A) containing titanium oxide as cores with a coating material (B), the coverage of particles (C) obtained by coating the particles (A) with the coating material (B) can be considered to be in a range of various application methods, from a coverage of 100%, which completely suppresses the photoactivity of titanium oxide, to a state in which the photoactivity of titanium oxide remains, in the range of 50 to 100%.

[0018] In the present invention, focusing on the fact that rutile-type titanium oxide can electrochemically insert and desorb lithium ions and that the coverage rate is inversely proportional to the charge capacity exhibited by the desorption of lithium ions, an electrochemical cell was prepared from a positive electrode material containing the above-mentioned metal oxide particles (C) and a negative electrode material made of lithium foil, and the charge capacity was measured. From these values, the coverage rate of the metal oxide particles (C) in which the surface of the metal oxide particles (A) containing titanium oxide as cores is coated with the coating material (B) was measured. In the present invention, the positive electrode is evaluated, and evaluation can be performed using a half cell using lithium foil as the negative electrode. Note that while rutile-type titanium oxide is excellent for high-speed charge and discharge, even anatase-type titanium oxide is capable of inserting and desorbing lithium ions at low speeds, and discharge capacity can be measured.

[0019] The present invention has made it possible for the first time to determine the coverage, and to obtain the metal oxide particles (C) having a coverage of 50 to 100%.Furthermore, the present invention has made it possible to obtain the metal oxide particles (C) having a coverage of 90 to 100%.

[0020] FIG. 1 is a schematic diagram of a coin cell used in a charge / discharge test. FIG. 2 is a diagram showing charge / discharge curves of a coin cell produced using metal oxide particles (C) obtained in Example 1. FIG. 3 is a diagram showing charge / discharge curves of a coin cell produced using metal oxide particles (C) obtained in Example 2. FIG. 4 is a diagram showing charge / discharge curves of a coin cell produced using metal oxide particles (C) obtained in Example 3. FIG. 5 is a diagram showing charge / discharge curves of a coin cell produced using metal oxide particles (C) obtained in Comparative Example 1. FIG. 6 is a diagram showing charge / discharge curves of a coin cell produced using metal oxide particles (C) obtained in Comparative Example 2. FIG. 7 is a diagram showing charge / discharge curves of a coin cell produced using metal oxide particles (C) obtained in Comparative Example 3.

[0021] Preferred embodiments of the present invention will be described below. However, the following embodiments are merely examples for explaining the present invention, and the present invention is not limited to the following embodiments. One embodiment of the present invention is metal oxide particles (C) in which the surfaces of titanium oxide-containing core particles (A) are coated with a coating material (B), and the coverage of particles (C) in which particles (A) are coated with coating material (B) is 50 to 100% as measured by the following measurement method.

[0022] The measurement method involves applying an electrode-forming composition comprising a binder, conductive carbon, and metal oxide particles (C), the composition containing 85% by mass of the metal oxide particles (C), to a thickness of 200 μm on copper foil, drying, and then extracting a film with an area of ​​13 mmφ. This film was used as the positive electrode, and a lithium foil with an area of ​​13 mmφ was used as the negative electrode. These were combined to prepare an electrochemical cell, and three cycles of charge and discharge were repeated in the range of 1.4 to 3.0 V to measure the average charge capacity (mAh / g). (Coverage rate of metal oxide particles (C) in which core metal oxide particles (A) are coated with coating material (B) %) = 100 - [(average charge capacity (mAh / g) of three charge / discharge cycles for each sample according to the above measurement method)) / (theoretical charge capacity of titanium oxide particles (mAh / g))] × 100], where the theoretical charge capacity of titanium oxide is 120 (mAh / g).

[0023] Metal oxide particles (C) having the above coverage of 60 to 100%, or 70 to 100%, or 80 to 100%, or 90 to 99%, or 90 to 100% can be obtained.

[0024] The metal oxide particles (C) may have a titanium oxide content of 50 mol % or more based on the total metal oxide content.

[0025] The core metal oxide particles (A) can be titanium oxide particles (A1) alone, or metal oxide particles (A2) containing titanium oxide and at least one metal oxide selected from the group consisting of tin oxide, zirconium oxide, silicon dioxide, zinc oxide, antimony oxide, niobium oxide, iron oxide, and tungsten oxide. Examples include titanium oxide particles, composite particles of titanium oxide particles and tin oxide particles, composite particles of titanium oxide particles and zirconium oxide particles, and composite particles of titanium oxide particles, tin oxide particles, and zirconium oxide particles. These particles have an average primary particle size of 5 to 500 nm, 5 to 300 nm, 5 to 250 nm, or 5 to 60 nm as determined by transmission electron microscope observation.

[0026] The coating (B) can be at least one coating selected from the group consisting of electrochemically inactive metal oxide particles (B1), amines (B2), silane coupling agents (B3), and organic acids and organic acid esters (B4). The electrochemically inactive metal oxide particles (B1) can be selected from metal oxides (B1) that are electrochemically inactive in the range of 1.4 to 3.0 V in a test of repeated charge and discharge in an electrochemical cell. The electrochemically inactive metal oxide particles (B1) can be selected from metal oxide particles (B1) consisting of a combination of at least one metal oxide selected from the group consisting of tin oxide, zirconium oxide, silicon dioxide, zinc oxide, antimony oxide, niobium oxide, iron oxide, and tungsten oxide. These have an average primary particle diameter of 1 to 10 nm or 1 to 5 nm as determined by transmission electron microscope observation.

[0027] When the electrochemical cell is composed of a half cell using lithium foil, for example, ZrO ２ is inactive, and SnO ２ and SiO ２ is active at 1.0 V or less but inactive at 1.4 to 3.0 V. If a charge / discharge test is performed using the metal oxide particles (C) (core-shell type metal oxide particles) in the range of 1.4 to 3.0 V and a charge / discharge capacity is exhibited, this indicates the presence of an uncoated portion of the core particle (particle A) that is exposed, and the coverage of particles (C) in which particles (A) are coated with coating (B) can be measured electrochemically from the exhibited charge capacity. Here, the reason for using charge capacity rather than discharge capacity in calculating the coverage rate is that irreversible capacity resulting from the formation of an SEI (Solid Electrolyte Interphase) coating on the negative electrode surface during the initial discharge process is exhibited, and it is difficult to distinguish this from the capacity resulting from the insertion of lithium ions into titanium oxide.

[0028] Therefore, when the metal oxide particles (A) are titanium oxide, or titanium oxide and at least one metal oxide particle selected from zirconium oxide, tin oxide, and silicon dioxide (silica), the charge capacity derived from the desorption of lithium ions from titanium oxide is measured.For example, as the core-shell type metal oxide particles composed of a combination of core particles and shell particles, the core particle / shell particle can be exemplified by the combination of titanium oxide particles / tin oxide and silicon dioxide composite particles, titanium oxide and tin oxide composite particles / tin oxide and silicon dioxide composite particles, titanium oxide particles and zirconium oxide particles composite particles / tin oxide and silicon dioxide composite particles, titanium oxide particles / antimony oxide particles, titanium oxide and tin oxide composite particles / antimony oxide particles.

[0029] The core-shell metal oxide particles can be produced by charging the metal oxide of the shell / metal oxide of the core in a mass ratio of 0.05 to 1.0, or 0.1 to 1.0, or 0.15 to 1.0.

[0030] In the present invention, an intermediate layer is present between the core particle and the shell particle, and the intermediate layer is a metal oxide particle composed of a combination of at least one selected from the group consisting of zirconium oxide, silicon dioxide, aluminum oxide, tin oxide, zinc oxide, iron oxide, niobium oxide, tantalum oxide, antimony oxide, and tungsten oxide as component (D), and can be produced by charging and producing the intermediate layer in such a way that the mass ratio of (metal oxide other than the core) / (metal oxide of the core) is in the range of 0.05 to 1.0, or 0.1 to 1.0, or 0.15 to 1.0.

[0031] When a core-shell structure is used, coating with a coating layer containing metal oxide particles having a metal oxide component or metal oxide content different from that of the metal oxide of the core can include cases where the metal oxide components of the core and the coating layer are different, or cases where the metal oxide components of the core and the coating partially overlap but the blending ratios of the metal oxides are different. For example, in the case of the tin oxide-silicon dioxide composite oxide (B1) contained in the metal oxide particles of the coating layer, sodium stannate or potassium stannate can be used as the alkali stannate, with sodium stannate being preferred.

[0032] As the alkali silicate, sodium silicate and potassium silicate can be used.

[0033] The alkali stannate and alkali silicate are prepared as an aqueous solution containing silicon dioxide / stannic oxide in a mass ratio of 0.1 to 5, and then the cations present in the aqueous solution are removed using a cation exchange resin. The alkali stannate and alkali silicate are weighed and dissolved in water so that the mass ratio of silicon dioxide / stannic oxide is 0.1 to 5.0. The preferred solid concentration of the aqueous solution is (SnO ２ +SiO ２ ) is 1 to 12 mass %.

[0034] The prepared aqueous solution is subjected to cation removal using a cation exchange resin. A hydrogen-type strongly acidic cation exchange resin is preferred as the cation exchange resin, and a column packed with Amberlite (trade name) 120B or the like can be used for cation exchange. By carrying out this cation exchange, the silicic acid component and the stannic acid component are polymerized, and silicon dioxide-stannic oxide composite colloidal particles having a primary particle size of 1 to 4 nm can be produced.

[0035] The silicon dioxide-stannic oxide composite colloidal particles are poorly stable and gel within a few hours of standing. Therefore, after the cation exchange, an amine compound is quickly added to stabilize the particles, resulting in a silicon dioxide / stannic oxide composite colloidal particle having a mass ratio of 0.1 to 5.0 and an M / (SnO ２ +SiO ２It is necessary to obtain an aqueous sol of silicon dioxide-stannic oxide composite oxide colloidal particles having a primary particle size of 1 to 4 nm stabilized by an amine compound present in a molar ratio of (SnO ２ +SiO ２ ) is 0.1 to 10 mass %.

[0036] To stabilize the silicon dioxide-stannic oxide composite colloidal particles produced by the cation exchange, M / (SnO ２ +SiO ２ It is appropriate to add the amine compound in an amount such that the molar ratio of M / (SnO) (where M represents an amine compound) is 0.1 to 1.0. ２ +SiO ２ Addition of an amine compound in which the molar ratio of 1 to 2 is less than 0.1 to 1.0 is not preferred because the composition loses stability and gels after standing for several hours.

[0037] Next, an aqueous sol of metal oxide colloid particles (A) to be used for the cores, which have a primary particle size of 5 to 60 nm, and a silicon dioxide / stannic oxide mass ratio of 0.1 to 5.0 and an M / (SnO ２ +SiO ２ ) (where M represents an amine compound) in a molar ratio of 0.05 to 0.50, an aqueous sol of modified metal oxide colloid particles (C) in which the metal oxide colloid particles (A) are coated with the silicon dioxide-stannic oxide composite oxide colloid particles (B1) can be obtained by mixing the silicon dioxide-stannic oxide composite oxide colloid particles (B1) having a primary particle size of 1 to 4 nm stabilized with an amine compound in a molar ratio of 0.05 to 0.50, an aqueous sol of modified metal oxide colloid particles (C) in which the metal oxide colloid particles (A) are coated with the silicon dioxide-stannic oxide composite oxide colloid particles (B1).

[0038] The solids concentration of the aqueous sol of the metal oxide colloidal particles (A) is 0.5 to 50% by mass, preferably 5 to 30% by mass. The aqueous sol of the metal oxide colloidal particles (A) can have a pH of 5 to 11.5, preferably 7 to 11.5. The pH of the aqueous sol can be adjusted as needed with an alkaline component. Examples of the alkaline component include hydroxides of alkali metals such as lithium, sodium, and potassium; hydroxides of alkaline earth metals such as calcium, magnesium, and strontium; ammonia; alkylamines such as ethylamine, triethylamine, isopropylamine, and n-propylamine; aralkylamines such as benzylamine; alicyclic amines such as piperidine; alkanolamines such as monoethanolamine and triethanolamine; and quaternary ammonium hydroxides.

[0039] The aqueous sol of the metal oxide colloid particles (A) and the aqueous sol of the coated particles (B1) are preferably mixed under stirring. The mixing ratio of the silicon dioxide-stannic oxide composite oxide colloid particles (B1) to the metal oxide colloid particles (A) is preferably 0.05 to 0.50 in terms of mass ratio (B1) / (A). If the mass ratio is less than 0.05, the metal oxide colloid particles (A) serving as cores cannot be sufficiently coated with the silicon dioxide-stannic oxide composite oxide colloid particles (B1), and a stable hydrophilic organic solvent dispersion sol or a hydrophobic organic solvent dispersion sol having a water solubility of 0.05 to 12% by mass cannot be obtained. Furthermore, a mass ratio of 0.50 is sufficient, and if it exceeds 0.50, it is not efficient.

[0040] The aqueous sol of the metal oxide colloid particles (A) and the aqueous sol of the coated particles (B1) can be mixed at a rate of 22 to 1,000 parts by mass per minute of the solids content of one sol added to the container per 100 parts by mass of the solids content of the other sol. The resulting aqueous sol of modified metal oxide colloid particles (C) is then subjected to cation exchange. A strongly acidic hydrogen-type cation exchange resin is preferably used for the cation exchange.

[0041] Next, the obtained aqueous sol was mixed with the silicon dioxide-stannic oxide composite oxide colloidal particles (B1) at a molar ratio of M / (SnO ２ +SiO ２ The amount of the amine compound added is such that the ratio M / (SnO ２ +SiO ２ If the molar ratio of M / (SnO) is less than 0.001, the dispersion stability of the hydrophilic organic solvent dispersion sol of the present invention becomes insufficient, which is not preferable. ２ +SiO ２ If the molar ratio of (C) exceeds 0.08, bonding of a silane compound to the particle surface of the modified metal oxide colloidal particles (C) may be hindered.

[0042] Next, the aqueous medium of the obtained aqueous sol is replaced with a hydrophilic organic solvent. The method for replacing the dispersion medium from water to a hydrophilic organic solvent can be a known method, such as evaporation replacement under normal or reduced pressure, ultrafiltration membrane method, or solvent extraction method. To efficiently perform the solvent replacement, the obtained aqueous sol is preferably concentrated in advance so that the concentration of the modified metal oxide colloidal particles (C) contained therein is in the range of 1 to 70% by mass, or 10 to 50% by mass. The sol can be concentrated by known methods such as thermal evaporation or ultrafiltration. The temperature of the sol during the solvent replacement is in the range from room temperature to the boiling point of the hydrophilic solvent. The solvent replacement is performed until the water content in the sol is less than 5% by mass. The solids concentration of the obtained sol is 20 to 70% by mass, as the total metal oxide concentration of the modified metal oxide colloidal particles (C).

[0043] The dispersion medium for the sol can be water or an organic solvent such as an alcohol, ester, ketone, amide, or hydrocarbon. Examples of the organic solvent include alcohols, esters, ketones, amides, or hydrocarbons having 1 to 10 carbon atoms, which may have an ether bond. Examples of alcohols having 1 to 10 carbon atoms include methanol, ethanol, n-propanol, i-propanol, n-butanol, isobutanol, n-pentanol, ethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol monopropyl ether.

[0044] Examples of ketones include linear or cyclic aliphatic ketones having 3 to 30 carbon atoms, such as methyl ethyl ketone, diethyl ketone, methyl propyl ketone, methyl isobutyl ketone, diisopropyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, etc. Examples of ethers include linear or cyclic aliphatic ethers having 3 to 30 carbon atoms, such as diethyl ether, tetrahydrofuran, etc.

[0045] Examples of esters include linear or cyclic esters having 2 to 30 carbon atoms, such as ethyl acetate, n-butyl acetate, sec-butyl acetate, methoxybutyl acetate, amyl acetate, n-propyl acetate, isopropyl acetate, ethyl lactate, butyl lactate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, phenyl acetate, phenyl lactate, and phenyl propionate. Examples of amides include aliphatic amides having 3 to 30 carbon atoms, such as dimethylacetamide, dimethylformamide, N-methylpyrrolidone, and N-ethylpyrrolidone. Examples of hydrocarbons include linear or cyclic aliphatic or aromatic hydrocarbons having 6 to 30 carbon atoms, such as hexane, heptane, octane, nonane, decane, benzene, toluene, and xylene.

[0046] The amine (B2) used as the coating agent in the present invention can be a secondary amine or a tertiary amine having a total of 5 to 35 carbon atoms. These amines (B2) can be charged and produced at a pH in the range of 5 to 11.5, preferably 7 to 11.5. Examples of the secondary amine include ethyl n-propylamine, ethylisopropylamine, dipropylamine, diisopropylamine, ethylbutylamine, n-propylbutylamine, dibutylamine, ethylpentylamine, n-propylpentylamine, isopropylpentylamine, dipentylamine, ethyloctylamine, i-propyloctylamine, butyloctylamine, and dioctylamine.

[0047] Examples of the tertiary amine include triethylamine, ethyldi-n-propylamine, diethyl-n-propylamine, tri-n-propylamine, triisopropylamine, ethyldibutylamine, diethylbutylamine, isopropyldibutylamine, diisopropylethylamine, diisopropylbutylamine, tributylamine, ethyldipentylamine, diethylpentylamine, tripentylamine, methyldioctylamine, dimethyloctylamine, ethyldioctylamine, diethyloctylamine, trioctylamine, benzyldibutylamine, diazabicycloundecene, etc. Among the above amines, secondary amines and tertiary amines having an alkyl group having a total of 6 to 35 carbon atoms are preferred, such as diisopropylamine, tripentylamine, triisopropylamine, dimethyloctylamine, trioctylamine, etc.

[0048] The silane coupling agent (B3) used as a coating agent in the present invention can be coated with a hydrolyzate of at least one silane compound selected from the group consisting of formulas (1) to (3).

[0049] In formula (1), R １are each an alkyl group, a halogenated alkyl group, an alkenyl group, an aryl group, or an organic group having a polyether group, an epoxy group, a (meth)acryloyl group, a mercapto group, an amino group, a ureido group, an acid anhydride group, or a cyano group, and are bonded to a silicon atom by a Si—C bond, and R ２ represents an alkoxy group, an acyloxy group, or a halogen group, and a represents an integer of 1 to 3. In formulas (2) and (3), R ３ and R ５ are each an alkyl group having 1 to 3 carbon atoms or an aryl group having 6 to 30 carbon atoms and bonded to a silicon atom by a Si—C bond, and R ４ and R ６ each represents an alkoxy group, an acyloxy group, or a halogen group; Y represents an alkylene group, an NH group, or an oxygen atom; b is an integer of 1 to 3; c is an integer of 0 or 1; and d is an integer of 1 to 3.

[0050] The alkyl group is an alkyl group having 1 to 18 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, a cyclopropyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, a cyclobutyl group, a 1-methyl-cyclopropyl group, a 2-methyl-cyclopropyl group, an n-pentyl group, a 1-methyl-n-butyl group, a 2-methyl-n-butyl group, a 3-methyl-n-butyl group, a 1,1-dimethyl-n-propyl group, a 1,2-dimethyl-n-propyl group, a 2,2-dimethyl-n-propyl group, a 1-ethyl- n-propyl group, cyclopentyl group, 1-methyl-cyclobutyl group, 2-methyl-cyclobutyl group, 3-methyl-cyclobutyl group, 1,2-dimethyl-cyclopropyl group, 2,3-dimethyl-cyclopropyl group, 1-ethyl-cyclopropyl group, 2-ethyl-cyclopropyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-dimethyl-n-butyl group , 2,2-dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, cyclohexyl group, 1-methyl-cyclopentyl group, 2-methyl-cyclopentyl group, 3-methyl-cyclopentyl group, 1-ethyl-cyclobutyl group, 2-ethyl-cyclobutyl group group, 3-ethyl-cyclobutyl group, 1,2-dimethyl-cyclobutyl group, 1,3-dimethyl-cyclobutyl group, 2,2-dimethyl-cyclobutyl group, 2,3-dimethyl-cyclobutyl group, 2,4-dimethyl-cyclobutyl group, 3,3-dimethyl-cyclobutyl group, 1-n-propyl-cyclopropyl group, 2-n-propyl-cyclopropyl group, 1-i-propyl-cyclopropyl group, 2-i-propyl-cyclopropyl group, 1,2,2-trimethyl-cyclopropyl group, 1,2,3-trimethyl-cyclopropyl group, 2,2,Examples of the cyclopropyl group include, but are not limited to, 3-trimethyl-cyclopropyl, 1-ethyl-2-methyl-cyclopropyl, 2-ethyl-1-methyl-cyclopropyl, 2-ethyl-2-methyl-cyclopropyl, and 2-ethyl-3-methyl-cyclopropyl groups, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups.

[0051] The alkylene group may be an alkylene group derived from the alkyl group described above. The aryl group is an aryl group having 6 to 30 carbon atoms, such as a phenyl group, a naphthyl group, an anthracene group, or a pyrene group.

[0052] The alkenyl group is an alkenyl group having 2 to 10 carbon atoms, such as ethenyl group, 1-propenyl group, 2-propenyl group, 1-methyl-1-ethenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenyl group, 1-methyl-1-propenyl group, 1-methyl-2-propenyl group, 1-pentenyl group, 2-pentenyl group, 3-pentenyl group, 4-pentenyl group, 1-n-propylethenyl group, 1-methyl-1-butenyl group, 1-methyl-2-butenyl group, 1-methyl-3-butenyl group, 2-ethyl-2-propenyl group, 2-methyl-1-butenyl group, 2-methyl-2-butenyl group, 2-methyl-3-butenyl group, 3 Examples of alkyl groups include, but are not limited to, 1-methyl-1-butenyl group, 3-methyl-2-butenyl group, 3-methyl-3-butenyl group, 1,1-dimethyl-2-propenyl group, 1-i-propylethenyl group, 1,2-dimethyl-1-propenyl group, 1,2-dimethyl-2-propenyl group, 1-cyclopentenyl group, 2-cyclopentenyl group, 3-cyclopentenyl group, 1-hexenyl group, 2-hexenyl group, 3-hexenyl group, 4-hexenyl group, 5-hexenyl group, 1-methyl-1-pentenyl group, 1-methyl-2-pentenyl group, 1-methyl-3-pentenyl group, 1-methyl-4-pentenyl group, 1-n-butylethenyl group, 2-methyl-1-pentenyl group, and 2-methyl-2-pentenyl group.

[0053] The alkoxy group includes alkoxy groups having 1 to 10 carbon atoms, such as methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentyloxy, 1-methyl-n-butoxy, 2-methyl-n-butoxy, 3-methyl-n-butoxy, 1,1-dimethyl-n-propoxy, 1,2-dimethyl-n-propoxy, 2,2-dimethyl-n-propoxy, 1-ethyl-n-propoxy, and n-hexyloxy, but is not limited to these.

[0054] Examples of the acyloxy group having 2 to 10 carbon atoms include, but are not limited to, a methylcarbonyloxy group, an ethylcarbonyloxy group, an n-propylcarbonyloxy group, an i-propylcarbonyloxy group, an n-butylcarbonyloxy group, an i-butylcarbonyloxy group, an s-butylcarbonyloxy group, a t-butylcarbonyloxy group, an n-pentylcarbonyloxy group, a 1-methyl-n-butylcarbonyloxy group, a 2-methyl-n-butylcarbonyloxy group, a 3-methyl-n-butylcarbonyloxy group, a 1,1-dimethyl-n-propylcarbonyloxy group, a 1,2-dimethyl-n-propylcarbonyloxy group, a 2,2-dimethyl-n-propylcarbonyloxy group, a 1-ethyl-n-propylcarbonyloxy group, an n-hexylcarbonyloxy group, a 1-methyl-n-pentylcarbonyloxy group, and a 2-methyl-n-pentylcarbonyloxy group. Examples of the halogen group include fluorine, chlorine, bromine, and iodine.

[0055] The organic group having a polyether group includes a polyetherpropyl group having an alkoxy group. For example, (CH ３ O) ３ SiC ３ H ６ (OC ２ H ４ ) nOCH ３n can be in the range of 1 to 100, or 1 to 10. Examples of organic groups having an epoxy group include a 2-(3,4-epoxycyclohexyl)ethyl group and a 3-glycidoxypropyl group. The (meth)acryloyl group refers to both an acryloyl group and a methacryloyl group. Examples of organic groups having a (meth)acryloyl group include a 3-methacryloxypropyl group and a 3-acryloxypropyl group.

[0056] Examples of organic groups having a mercapto group include a 3-mercaptopropyl group. Examples of organic groups having an amino group include a 2-aminoethyl group, a 3-aminopropyl group, an N-2-(aminoethyl)-3-aminopropyl group, an N-(1,3-dimethyl-butylidene)aminopropyl group, an N-phenyl-3-aminopropyl group, and an N-(vinylbenzyl)-2-aminoethyl-3-aminopropyl group.

[0057] An example of an organic group having a ureido group is a 3-ureidopropyl group. An example of an organic group having an acid anhydride group is a 3-propylsuccinic anhydride group. An example of an organic group having a cyano group is a 3-cyanopropyl group.

[0058] The compounds represented by the formulas (2) and (3) are preferably compounds capable of forming trimethylsilyl groups on the surface of silica particles. Examples of such compounds include the following:

[0059]

[0060] In the above formula, R １２is an alkoxy group, for example, a methoxy group or an ethoxy group. As the silane compound, a silane compound manufactured by Shin-Etsu Chemical Co., Ltd. can be used. This is a process in which the silane compound reacts with a hydroxyl group on the surface of silica particles, for example, a silanol group in the case of silica particles, to coat the surface of the silica particles with the silane compound through a siloxane bond. The reaction temperature can be from 20°C to the boiling point of the dispersion medium, for example, in the range of 20°C to 100°C. The reaction time can be about 0.1 to 6 hours.

[0061] The silane compound is applied to the surface of the silica particles in such an amount that the number of silicon atoms in the silane compound is 0.1 / nm ２ ~6.0 pieces / nm ２ The surface of the silica particles can be coated by adding a silane compound corresponding to the coating amount of the above to the silica sol.

[0062] Water is required for the hydrolysis of the silane compound, and if the sol is an aqueous solvent, the aqueous solvent can be used. When the aqueous medium is replaced with the organic solvent (C), the water remaining in the solvent can be used. For example, the water present in an amount of 0.01 to 1% by mass can be used.

[0063] Hydrolysis can be carried out with or without a catalyst. When hydrolysis is carried out without a catalyst, the silica particle surface is acidic. When hydrolysis is carried out with a catalyst, examples of hydrolysis catalysts include metal chelate compounds, organic acids, inorganic acids, organic bases, and inorganic bases. Examples of metal chelate compounds used as hydrolysis catalysts include triethoxy mono(acetylacetonato)titanium and triethoxy mono(acetylacetonato)zirconium. Examples of organic acids used as hydrolysis catalysts include acetic acid and oxalic acid. Examples of inorganic acids used as hydrolysis catalysts include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, and phosphoric acid. Examples of organic bases used as hydrolysis catalysts include pyridine, pyrrole, piperazine, and quaternary ammonium salts. Examples of inorganic bases used as hydrolysis catalysts include ammonia, sodium hydroxide, and potassium hydroxide.

[0064] The organic acid and organic acid ester (B4) used as the coating agent in the present invention include acetic acid, benzoic acid, and their alkyl, aryl, or arylalkyl esters. The alkyl and aryl groups are exemplified by those listed above, and the arylalkyl groups can be used in combination. The amount of the organic acid and its ester added is determined by the SiO ２ The concentration can be set to 0.01 to 10.0 mmol, or 0.01 to 5.0 mmol per 100 g of the compound.

[0065] The method for producing the metal oxide sol can include the following steps (i) to (iii): step (i): a step (i) of solvent-substituting the aqueous solvent of the aqueous sol of metal oxide particles (A) with an alcohol having 1 to 4 carbon atoms which may have an ether bond; step (ii): a step (ii) of mixing the alcohol sol of metal oxide particles obtained in step (i) with a coating material (B); and step (iii): a step (iii) of solvent-substituting the alcohol solvent of the alcohol sol of metal oxide particles obtained in step (ii) with an organic solvent other than the alcohol.

[0066] The composition obtained through the above production method has a solids content of 0.1 to 70 mass %, and the photoactive metal oxide particles (A) can be set to 80 to 99 mass % and the dispersant to 1 to 20 mass % of the total solids content.

[0067] Here, the solid content refers to the components of the composition excluding the solvent component, and the solid content concentration refers to the concentration of the solid content in the composition. The dispersion medium for the sol can be water or an organic solvent such as an alcohol, ester, ketone, amide, or hydrocarbon. Examples of the organic solvent include alcohols, esters, ketones, amides, or hydrocarbons having 1 to 10 carbon atoms, which may have an ether bond.

[0068] Examples of the alcohol having 1 to 10 carbon atoms include methanol, ethanol, n-propanol, i-propanol, n-butanol, isobutanol, n-pentanol, ethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and propylene glycol monopropyl ether.

[0069] The ketone may be a linear or cyclic aliphatic ketone having 3 to 30 carbon atoms, such as methyl ethyl ketone, diethyl ketone, methyl propyl ketone, methyl isobutyl ketone, diisopropyl ketone, diisobutyl ketone, methyl amyl ketone, or cyclohexanone.

[0070] Examples of ethers include linear or cyclic aliphatic ethers having 3 to 30 carbon atoms, such as diethyl ether and tetrahydrofuran. Examples of esters include linear or cyclic esters having 2 to 30 carbon atoms, such as ethyl acetate, n-butyl acetate, sec-butyl acetate, methoxybutyl acetate, amyl acetate, n-propyl acetate, isopropyl acetate, ethyl lactate, butyl lactate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, phenyl acetate, phenyl lactate, and phenyl propionate. Examples of amides include aliphatic amides having 3 to 30 carbon atoms, such as dimethylacetamide, dimethylformamide, N-methylpyrrolidone, and N-ethylpyrrolidone. Examples of hydrocarbons include linear or cyclic aliphatic or aromatic hydrocarbons having 6 to 30 carbon atoms, such as hexane, heptane, octane, nonane, decane, benzene, toluene, and xylene.

[0071] In the present invention, the measurement method involves applying an electrode-forming composition comprising a binder, conductive carbon, and metal oxide particles (C), the composition containing 85% by mass of the metal oxide particles (C), to a thickness of 200 μm on copper foil, drying, and then extracting a film having an area of ​​13 mmφ. This film serves as the positive electrode, and a lithium foil having an area of ​​13 mmφ serves as the negative electrode. These are combined to prepare an electrochemical cell, and three cycles of charge and discharge are repeated in the range of 1.4 to 3.0 V to measure the average charge capacity (mAh / g). (Coverage rate of metal oxide particles (C) in which core metal oxide particles (A) are coated with coating material (B) %) = 100 - [(average charge capacity (mAh / g) of three charge / discharge cycles for each sample according to the above measurement method)) / (theoretical charge capacity of titanium oxide particles (mAh / g))] × 100], where the theoretical charge capacity of titanium oxide is 120 (mAh / g).

[0072] In the above measurement method, a cellulose-based binder can be used. Modified cellulose can be used. Examples include carboxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cetyl cellulose. After adding water and a binder to a kneader (e.g., kneading with a mortar and pestle) and kneading, water and metal oxide particles (C) are added and further kneaded, and then water and conductive carbon are added and further kneaded to form a slurry (electrode-forming composition). The metal oxide particles (C) are preferably subjected to ion exchange to remove unnecessary ions and then dried. Examples of conductive carbon include acetylene black, ketjen black, and carbon nanotubes. The metal oxide particles (C) are preferably adjusted to 85% by mass in the electrode-forming composition. An electrode-forming composition slurry can be formed in which the binder, conductive carbon, and metal oxide particles (C) have a mass ratio of, for example, 5:10:85.

[0073] The electrode sheet can be produced by applying the electrode-forming composition slurry to a copper foil using a doctor blade to a thickness of 200 μm, pre-drying at 80° C. for 30 minutes, and then fully drying at 120° C. for 12 hours. The copper foil is preferably pre-dried at 80° C. for 30 minutes.

[0074] Copper foil can be used in a thickness range of 8 to 10 μm. The electrode sheet can be cut out with an area of ​​13 mmφ and used as a positive electrode. High-purity lithium metal with a purity of 99.9% or more can be used for the lithium foil. The lithium foil can be set to any thickness, for example, in the range of several tens of μm to several hundred μm, and can be used as a negative electrode.

[0075] A stainless steel coin cell can be used as the electrochemical cell. For example, an R2032 type coin cell (diameter 20 mm, thickness 3.2 mm) can be used, and the negative and positive electrodes can each be 13 mmφ. The coin cell is formed by stacking a case, gasket, positive electrode, separator, negative electrode, spacer, wave washer, and cap in this order. The separator is made of a material such as polyester, aromatic polyamide, polyphenylene sulfide, or polyolefin, and preferably has a molecular weight (weight average molecular weight: Mw) of 5,000 or more. For example, the average film thickness is 10 to 35 μm, and the basis weight is 10 to 25 g / m. ２ For example, polyethylene terephthalate (PET) can have an average film thickness of 18 μm, an air permeability of 0.07 seconds, a puncture strength of 5.0 g / μm (90 g), and a MacMillan number of 5.0 (MacMillan number × film thickness = 90 μm).

[0076] Also, a polypropylene (PP) microporous film (trade name Celgard 2400, manufactured by Celgard) with an average film thickness of 25 μm and a basis weight of 13.5 g / m ２ The McMillan number is an index of ionic conductivity, and is the ratio of the impedance when the membrane is impregnated with an electrolyte solution to the impedance of the electrolyte solution alone.

[0077] A non-aqueous electrolyte is used as the electrolyte, and examples thereof include propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC), vinylene carbonate (VC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEC), ethyl methyl carbonate (EMC), 1,2-dimethoxyethane (DME), 1,2-diethoxyethane (DEE), γ-butyrolactone (γ-BL), sulfolane, acetonitrile, and the like. These non-aqueous solvents may be used alone or in combination of two or more. Examples of lithium salts that dissolve in non-aqueous solvents include lithium perchlorate (LiClO ４ ), lithium hexafluorophosphate (LiPF ６ ), lithium boron tetrafluoride (LiBF ４ ), lithium arsenic hexafluoride (LiAsF ６ ), lithium trifluorosulfonate (CF ３ SO ３ Li), lithium perfluoromethylsulfonylimide [LiN(CF ３ SO ２ ) ２ ] and lithium perfluoroethylsulfonylimide [LiN(C ２ F ５ SO ２ ) ２ These may be used in combination of two or more. The concentration of the dissolved lithium salt is preferably in the range of 0.2 to 2 M (mol / L).

[0078] For example, 1M concentration of lithium hexafluorophosphate (LiPF ６ An electrolyte solution prepared by dissolving ethylene carbonate (EC) and ethyl methyl carbonate (EMC) in a volume ratio of 3:7 can be used. These electrolytes are available from Kishida Corporation.

[0079] The charge-discharge test conditions can be as follows: a charge-discharge tester, such as a Toyo Systems Co., Ltd. product name TOSCAT-3100, can be used. The charge-discharge test can be performed by a constant current charge-discharge test. This allows the cycle characteristics to be evaluated by repeating charge and discharge at a constant current value. ２ The theoretical charge capacity of this battery can be estimated as 120 mAh / g. This is based on the values ​​described in Electrochemistry, 90(3), 037002(2022) (H. Sakuguchi, H. Usui, et al.). The current density is 12 mAh / g, which is the C / 10 value. The current required to fully charge (or discharge) the theoretical capacity in 1 hour is defined as 1 C, and C / 10 means a full charge in 10 hours. The rest time between charge and discharge is 5 minutes. Measurements can be performed over a voltage range of 1.4 to 3.0 V.

[0080] Charge and discharge are repeated three times in the range of 1.4 to 3.0 V, and a charge and discharge curve is drawn with the vertical axis representing voltage (V) and the horizontal axis representing capacity (mAh / g (g is the mass of titanium oxide in the positive electrode active material)). The average charge capacity over the three charge and discharge cycles is measured, and the coverage can be calculated by applying this to the formula for calculating the coverage.

[0081] In the present invention, in core-shell metal oxide particles (C) in which the surface of metal oxide particles (A) containing titanium oxide as a core (nucleus) is coated with a coating material (B) that forms a shell, the coverage of particles (C) obtained by coating particles (A) with coating material (B) is in the range of 50 to 100%. Metal oxide particles (A) containing photoactive titanium oxide are metal oxide particles (C) coated with coating material (B) at a coverage of 50 to 100%, so that the photoactivity of titanium oxide can be suppressed within a desired range. The fact that the photoactivity of titanium oxide in metal oxide particles (C) has been suppressed within a desired range can be evaluated by a light resistance test.

[0082] A dispersion of the metal oxide particles (C) containing 0.5% by mass of solids in a liquid consisting of water and methanol in a 1:1 mass ratio, and a solution of a dye (Sunset Yellow) containing 0.02% by mass in glycerin were mixed in a mass ratio of 1:3, and the mixture was irradiated with ultraviolet light having a wavelength of 365 nm at an intensity of 0.4 mW / cm. ２ The fading rate of the dye in the sample exposed to light for 180 minutes at 1000 K (at 2000 K) is 20% or less, or 18% or less. It is known that when a similar test was performed using only a 0.02% by mass dye (Sunset Yellow) solution in glycerin without containing metal oxide particles (C), the fading rate was 1%. The fading rate tends to decrease as the coverage of the core-shell metal oxide particles increases. Therefore, by evaluating the coverage of the core-shell metal oxide particles using an electrochemical method, it is possible to design core-shell metal oxide particles with the desired light resistance. Sunset Yellow is a dye having the following structure:

[0083]

[0084] The present invention can produce a varnish containing metal oxide particles (C) or a sol thereof and a thermosetting or photosetting resin.

[0085] The varnish can be used as a varnish for improving light resistance. The varnish can also be used as a coating agent for eyeglass lenses.

[0086] In the present invention, a composition (varnish) containing metal oxide particles (C) (core-shell type metal oxide particles) and a thermosetting or photocurable resin is obtained. The composition of the present invention can be further mixed with a thermosetting or photocurable resin to produce a varnish.

[0087] The present invention can also be used in a method for forming a pattern using a lithography method. The present invention provides a film-forming composition containing the organic solvent sol and an organic resin. The film-forming composition can be obtained by removing the organic solvent from the organic solvent sol to provide a film-forming composition containing core-shell metal oxide particles and an organic resin.

[0088] In the case of a thermosetting coating-forming composition, the heat curing agent can be added in the range of 0.01 to 50 phr, or 0.01 to 10 phr, relative to the resin containing a functional group such as an epoxy group or a (meth)acryloyl group, and for example, the heat curing agent can be contained in a ratio of 0.5 to 1.5 equivalents, preferably 0.8 to 1.2 equivalents, relative to the functional group such as an epoxy group or a (meth)acryloyl group. The equivalent of the heat curing agent relative to the curable resin is expressed as the equivalent ratio of the heat curing agent to the functional group.

[0089] Examples of heat curing agents include phenolic resins, amine-based curing agents, polyamide resins, imidazoles, polymercaptans, acid anhydrides, thermal radical generators, and thermal acid generators. Radical generator-based curing agents, acid anhydride-based curing agents, and amine-based curing agents are particularly preferred. These solid heat curing agents can be used by dissolving them in a solvent, but evaporation of the solvent can reduce the density of the cured product and create pores, resulting in reduced strength and reduced water resistance. Therefore, it is preferable for the curing agent itself to be liquid at room temperature and normal pressure. Examples of phenolic resins include phenol novolac resins and cresol novolac resins.

[0090] Examples of amine curing agents include piperidine, N,N-dimethylpiperazine, triethylenediamine, 2,4,6-tris(dimethylaminomethyl)phenol, benzyldimethylamine, 2-(dimethylaminomethyl)phenol, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diethylaminopropylamine, N-aminoethylpiperazine, di(1-methyl-2-aminocyclohexyl)methane, menthenediamine, isophoronediamine, diaminodicyclohexylmethane, 1,3-diaminomethylcyclohexane, xylenediamine, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, 3,3'-diethyl-4,4'-diaminodiphenylmethane, and diethyltoluenediamine. Of these, liquids such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diethylaminopropylamine, N-aminoethylpiperazine, di(1-methyl-2-aminocyclohexyl)methane, menthenediamine, isophoronediamine, diaminodicyclohexylmethane, 3,3'-diethyl-4,4'-diaminodiphenylmethane, and diethyltoluenediamine can be preferably used.

[0091] The polyamide resin is produced by condensation of dimer acid and polyamine, and is a polyamide amine having a primary amine and a secondary amine in the molecule.

[0092] Examples of imidazoles include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, and epoxyimidazole adduct.

[0093] The polymercaptan is preferably one in which a mercaptan group is present at the end of a polypropylene glycol chain or one in which a mercaptan group is present at the end of a polyethylene glycol chain, and is preferably liquid.

[0094] As the acid anhydride curing agent, an anhydride of a compound having a plurality of carboxyl groups in one molecule is preferred.These acid anhydride curing agents include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimellitate, glycerol tristrimellitate, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, endomethylene tetrahydrophthalic anhydride, methylendomethylene tetrahydrophthalic anhydride, methylbutenyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride, methylcyclohexene dicarboxylic anhydride, chlorendic anhydride, etc.As the thermal acid generator, sulfonium salts and phosphonium salts are mentioned, and sulfonium salts are preferably used.For example, the following compounds can be mentioned.

[0095]

[0096] R may be an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 20 carbon atoms, with an alkyl group having 1 to 12 carbon atoms being particularly preferred. Among these, the following are preferred, which are liquid at room temperature and normal pressure: methyltetrahydrophthalic anhydride, methyl-5-norbornene-2,3-dicarboxylic anhydride (methylnadic anhydride, methylhimic anhydride), hydrogenated methylnadic anhydride, methylbutenyltetrahydrophthalic anhydride, dodecenylsuccinic anhydride, methylhexahydrophthalic anhydride, and a mixture of methylhexahydrophthalic anhydride and hexahydrophthalic anhydride. These liquid acid anhydrides have a viscosity of about 10 mPa·s to 1,000 mPa·s when measured at 25°C.

[0097] Examples of thermal radical generators include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(2-methylpropionate)dimethyl, 2,2'-azobis(2-methylpropionamidine) dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, tert-butyl hydroperoxide, cumene hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, and benzoyl peroxide. These are available from Tokyo Chemical Industry Co., Ltd.

[0098] Furthermore, when obtaining the cured product, a curing aid may be used in combination as appropriate. Examples of the curing aid include organic phosphorus compounds such as triphenylphosphine and tributylphosphine, quaternary phosphonium salts such as ethyltriphenylphosphonium bromide and methyltriphenylphosphonium diethyl phosphate, and quaternary ammonium salts such as 1,8-diazabicyclo(5,4,0)undecane-7-ene, salts of 1,8-diazabicyclo(5,4,0)undecane-7-ene and octylic acid, zinc octylate, and tetrabutylammonium bromide. These curing aids can be contained in a ratio of 0.001 to 0.1 parts by mass per part by mass of the curing agent.

[0099] The composition is prepared by mixing a resin, a curing agent, and optionally, a curing aid to obtain a thermosetting varnish. Mixing can be performed in a reaction vessel using a stirring blade or kneader. Mixing is performed by a heated mixing method at a temperature of 60°C to 100°C for 0.5 to 1 hour. The resulting curable film-forming composition is a thermosetting coating composition and has an appropriate viscosity for use, for example, as a liquid encapsulant. Liquid thermosetting film-forming compositions can be prepared to any viscosity and can be used as transparent encapsulants for LEDs and other devices by casting, potting, dispensing, printing, or other methods to partially encapsulate any desired location. The liquid thermosetting composition can be directly mounted on an LED or other device using the method described above, followed by drying and curing to obtain a cured epoxy resin product.

[0100] A thermosetting film-forming composition (thermosetting coating composition) is applied to a substrate and heated at a temperature of 80 to 200°C to obtain a cured product. In the case of a photocurable resin composition among the above film-forming compositions, a photocuring agent (photoradical generator, photoacid generator) can be added in a range of 0.01 to 50 phr, or 0.01 to 10 phr, to a resin containing a functional group such as an epoxy group or a (meth)acryloyl group. For example, the photocuring agent (photoradical generator, photoacid generator) can be added in a ratio of 0.5 to 1.5 equivalents, preferably 0.8 to 1.2 equivalents, to a functional group such as an epoxy group or a (meth)acryloyl group. The equivalent of the photocuring agent to the curable resin is expressed as the equivalent ratio of the photocuring agent to the functional group.

[0101] The photoradical generator is not particularly limited as long as it generates radicals directly or indirectly upon irradiation with light. Examples of the photoradical generator include photoradical polymerization initiators such as imidazole compounds, diazo compounds, bisimidazole compounds, N-arylglycine compounds, organic azide compounds, titanocene compounds, aluminate compounds, organic peroxides, N-alkoxypyridinium salt compounds, and thioxanthone compounds.

[0102] Examples of azide compounds include p-azidobenzaldehyde, p-azidoacetophenone, p-azidobenzoic acid, p-azidobenzalacetophenone, 4,4'-diazidochalcone, 4,4'-diazidodiphenyl sulfide, and 2,6-bis(4'-azidobenzal)-4-methylcyclohexanone. Examples of diazo compounds include 1-diazo-2,5-diethoxy-4-p-tolylmercaptobenzeneborofluoride, 1-diazo-4-N,N-dimethylaminobenzene chloride, and 1-diazo-4-N,N-diethylaminobenzeneborofluoride.

[0103] Examples of the bisimidazole compound include 2,2'-bis(o-chlorophenyl)-4,5,4',5'-tetrakis(3,4,5-trimethoxyphenyl)1,2'-bisimidazole and 2,2'-bis(o-chlorophenyl)4,5,4',5'-tetraphenyl-1,2'-bisimidazole.

[0104] Examples of titanocene compounds include dicyclopentadienyl-titanium-dichloride, dicyclopentadienyl-titanium-bisphenyl, dicyclopentadienyl-titanium-bis(2,3,4,5,6-pentafluorophenyl), dicyclopentadienyl-titanium-bis(2,3,5,6-tetrafluorophenyl), dicyclopentadienyl-titanium-bis(2,4,6-trifluorophenyl), dicyclopentadienyl-titanium-bis(2,6-difluorophenyl), dicyclopentadienyl bis(methylcyclopentadienyl)-titanium-bis(2,3,4,5,6-pentafluorophenyl), bis(methylcyclopentadienyl)-titanium-bis(2,3,5,6-tetrafluorophenyl), bis(methylcyclopentadienyl)-titanium-bis(2,6-difluorophenyl), and dicyclopentadienyl-titanium-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl).

[0105] Further examples of the photoradical generator include 1,3-di(tert-butyldioxycarbonyl)benzophenone, 3,3',4,4'-tetrakis(tert-butyldioxycarbonyl)benzophenone, 3-phenyl-5-isoxazolone, 2-mercaptobenzimidazole, 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone.

[0106] These photoradical polymerization agents are available, for example, as Irgacure TPO (component: 2,4,6-trimethylbenzoyldiphenylphosphine oxide) (c1-1-1), manufactured by BASF, Omnirad 819 (component: bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide) (c1-1-2), manufactured by IGM RESINS, and Irgacure 184 (component: 1-hydroxycyclohexylphenyl ketone) (c1-1-3).

[0107]

[0108] The photoacid generator is not particularly limited as long as it generates an acid directly or indirectly upon irradiation with light. Specific examples of the photoacid generator include triazine compounds, acetophenone derivative compounds, disulfone compounds, diazomethane compounds, sulfonic acid derivative compounds, onium salts such as iodonium salts, sulfonium salts, phosphonium salts, and selenium salts, metallocene complexes, and iron arene complexes.

[0109] Examples of the onium salt used as the photoacid generator include iodonium salts such as diphenyliodonium chloride, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium mesylate, diphenyliodonium tosylate, diphenyliodonium bromide, diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluoroantimonate, diphenyliodonium hexafluoroarsenate, bis(p-tert-butylphenyl)iodonium hexafluorophosphate, bis(p-tert-butylphenyl)iodonium mesylate, bis(p-tert-butylphenyl)iodonium tosylate, bis(p-tert-butylphenyl)iodonium trifluoromethanesulfonate, bis(p-tert-butylphenyl)iodonium )iodonium tetrafluoroborate, bis(p-tert-butylphenyl)iodonium chloride, bis(p-chlorophenyl)iodonium chloride, bis(p-chlorophenyl)iodonium tetrafluoroborate, and further bis(4-t-butylphenyl)iodonium hexafluorophosphate and other bis(alkylphenyl)iodonium salts; alkoxycarbonylalkoxy-trialkylaryl iodonium salts (for example, 4-[(1-ethoxycarbonyl-ethoxy)phenyl]-(2,4,6-trimethylphenyl)-iodonium hexafluorophosphate, etc.); and bis(alkoxyaryl)iodonium salts (for example, bis(alkoxyphenyl)iodonium salts such as (4-methoxyphenyl)phenyliodonium hexafluoroantimonate).

[0110] Examples of sulfonium salts include triphenylsulfonium salts such as triphenylsulfonium chloride, triphenylsulfonium bromide, tri(p-methoxyphenyl)sulfonium tetrafluoroborate, tri(p-methoxyphenyl)sulfonium hexafluorophosphonate, tri(p-ethoxyphenyl)sulfonium tetrafluoroborate, triphenylsulfonium triflate, triphenylsulfonium hexafluoroantimonate, and triphenylsulfonium hexafluorophosphate; and sulfonium salts such as (4-phenylthiophenyl)diphenylsulfonium hexafluoroantimonate, (4-phenylthiophenyl)diphenylsulfonium hexafluorophosphate, bis[4-(diphenylsulfonio)phenyl]sulfide-bis-hexafluoroantimonate, bis[4-(diphenylsulfonio)phenyl]sulfide-bis-hexafluorophosphate, and (4-methoxyphenyl)diphenylsulfonium hexafluoroantimonate.

[0111] Examples of the phosphonium salt include triphenylphosphonium chloride, triphenylphosphonium bromide, tri(p-methoxyphenyl)phosphonium tetrafluoroborate, tri(p-methoxyphenyl)phosphonium hexafluorophosphonate, tri(p-ethoxyphenyl)phosphonium tetrafluoroborate, 4-chlorobenzenediazonium hexafluorophosphate, and benzyltriphenylphosphonium hexafluoroantimonate.

[0112] Other examples include selenium salts such as triphenylselenium hexafluorophosphate, and metallocene complexes such as (η5 or η6-isopropylbenzene)(η5-cyclopentadienyl)iron(II) hexafluorophosphate.

[0113] In addition, the following compounds can also be used as the photoacid generator.

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123] As the photoacid generator, sulfonium salt compounds and iodonium salt compounds are preferred. The anion species thereof is CF ３ SO ３ － , C ４ F ９ SO ３ － , C ８ F １７ SO ３ － , camphorsulfonate anion, tosylate anion, BF ４ － , P.F. ６ － , AsF ６ － and SbF ６ － In particular, anion species such as phosphorus hexafluoride and antimony hexafluoride, which exhibit strong acidity, are preferred.

[0124] The film-forming composition of the present invention may contain conventional additives as needed. Examples of such additives include pigments, colorants, thickeners, sensitizers, antifoaming agents, coatability improvers, lubricants, stabilizers (antioxidants, heat stabilizers, light stabilizers, etc.), plasticizers, dissolution promoters, fillers, antistatic agents, etc. These additives may be used alone or in combination of two or more.

[0125] Examples of methods for applying the film-forming composition of the present invention include flow coating, spin coating, spray coating, screen printing, casting, bar coating, curtain coating, roll coating, gravure coating, dipping, and slit coating. In the present invention, the photo-coating composition (film-forming composition) can be applied to a substrate and cured by light irradiation. Heating can also be performed before or after light irradiation.

[0126] The thickness of the coating film can be selected from the range of about 0.01 μm to 10 mm depending on the application of the cured product, for example, when used as a photoresist it can be about 0.05 to 10 μm (particularly 0.1 to 5 μm), when used as a printed wiring board it can be about 5 μm to 5 mm (particularly 100 μm to 1 mm), and when used as an optical thin film it can be about 0.1 to 100 μm (particularly 0.3 to 50 μm). When a transparent coating is obtained, the visible light transmittance of the coating can be 80% or more, or 90% or more, typically 90 to 96%.

[0127] When a photoacid generator is used, the light to be irradiated or exposed may be, for example, gamma rays, X-rays, ultraviolet light, or visible light, and is usually visible light or ultraviolet light, particularly ultraviolet light. The wavelength of the light is, for example, about 150 to 800 nm, preferably about 150 to 600 nm, and more preferably about 150 to 400 nm. The amount of irradiation light varies depending on the thickness of the coating film, but is, for example, about 2 to 20,000 mJ / cm. ２ , preferably 5 to 5000 mJ / cm ２ It can be about.

[0128] The light source can be selected depending on the type of light to be exposed, and for example, in the case of ultraviolet light, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a deuterium lamp, a halogen lamp, laser light (helium-cadmium laser, excimer laser, etc.), etc. Such light irradiation causes the curing reaction of the composition to proceed.

[0129] When a thermal acid generator is used, or when a photoacid generator is used, the coating film is heated as needed after light irradiation, for example, at about 60 to 350° C., preferably about 100 to 300° C. The heating time can be selected from the range of 3 seconds or more (for example, about 3 seconds to 5 hours), for example, 5 seconds to 2 hours, preferably about 20 seconds to 30 minutes, and usually about 1 minute to 3 hours (for example, about 5 minutes to 2.5 hours).

[0130] Furthermore, when forming a pattern or an image (for example, when producing a printed wiring board, etc.), the coating film formed on the substrate may be subjected to pattern exposure, which may be performed by scanning with laser light or by irradiating with light through a photomask. The non-irradiated areas (unexposed parts) generated by such pattern exposure are developed (or dissolved) with a developer to form a pattern or an image.

[0131] The developer may be an aqueous alkaline solution or an organic solvent, such as an aqueous solution of an alkali metal hydroxide, such as potassium hydroxide, sodium hydroxide, potassium carbonate, or sodium carbonate, an aqueous solution of a quaternary ammonium hydroxide, such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, or choline, or an aqueous solution of an amine, such as ethanolamine, propylamine, or ethylenediamine.

[0132] The alkaline developer is generally an aqueous solution of 10% by mass or less, preferably 0.1 to 3.0% by mass. Furthermore, alcohols and surfactants can be added to the developer, each of which is preferably in an amount of 0.05 to 10 parts by mass per 100 parts by mass of the developer. Among these, an aqueous solution of 0.1 to 2.38% by mass of tetramethylammonium hydroxide can be used.

[0133] The organic solvent used as the developer may be any of the commonly used organic solvents, such as acetone, acetonitrile, toluene, dimethylformamide, methanol, ethanol, isopropanol, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, propylene glycol butyl ether, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate, ethyl lactate, cyclohexanone, etc. These may be used alone or in combination of two or more. Propylene glycol methyl ether, propylene glycol methyl ether acetate, ethyl lactate, etc. are particularly preferred.

[0134] In the present invention, an adhesion promoter can be added for the purpose of improving adhesion to the substrate after development. Examples of such adhesion promoters include chlorosilanes such as trimethylchlorosilane, dimethylvinylchlorosilane, methyldiphenylchlorosilane, and chloromethyldimethylchlorosilane; alkoxysilanes such as trimethylmethoxysilane, dimethyldiethoxysilane, methyldimethoxysilane, dimethylvinylethoxysilane, diphenyldimethoxysilane, and phenyltriethoxysilane; silazanes such as hexamethyldisilazane, N,N'-bis(trimethylsilyl)urea, dimethyltrimethylsilylamine, and trimethylsilylimidazole; vinyltrichlorosilane; and 3-chloropropyltrimethoxysilane. Examples of suitable adhesion promoters include silanes such as 3-aminopropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-(N-piperidinyl)propyltrimethoxysilane; heterocyclic compounds such as benzotriazole, benzimidazole, indazole, imidazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, urazole, thiouracil, mercaptoimidazole, and mercaptopyrimidine; and urea or thiourea compounds such as 1,1-dimethylurea and 1,3-dimethylurea. These adhesion promoters can be used alone or in combination of two or more. The amount of these adhesion promoters added is typically 18% by mass or less, preferably 0.0008 to 9% by mass, and more preferably 0.04 to 9% by mass, based on the solid content.

[0135] The present invention may contain a sensitizer. Usable sensitizers include anthracene, phenothiazene, perylene, thioxanthone, and benzophenone thioxanthone. Further examples of sensitizing dyes include thiopyrylium salt dyes, merocyanine dyes, quinoline dyes, styrylquinoline dyes, ketocoumarin dyes, thioxanthene dyes, xanthene dyes, oxonol dyes, cyanine dyes, rhodamine dyes, and pyrylium salt dyes. Anthracene sensitizers are particularly preferred. When used in combination with a cationic curing catalyst (radiation-sensitive cationic polymerization initiator), they dramatically improve sensitivity and also possess radical polymerization initiation capabilities. In hybrid systems that combine the cationic curing system and radical curing system of the present invention, the catalyst species can be simplified. Specific anthracene compounds that are effective include dibutoxyanthracene and dipropoxyanthraquinone. The amount of the sensitizer added is 0.01 to 20% by weight, preferably 0.01 to 10% by weight, based on the solid content.

[0136] The composition of the present invention can be photocured or thermally cured using a photoradical generator, a thermal radical generator, a photoacid generator, or a thermal acid generator. When a photoacid generator or a thermal acid generator is used, for example, commonly used epoxy curing agents (e.g., amines or acid anhydrides) are not used, or even if they are used, the content of these agents is extremely small, thereby improving the storage stability of the composition.

[0137] The above composition has been found to be applicable to photocationic polymerization. It has a higher curing rate than conventional liquid epoxy compounds (e.g., alicyclic epoxy compounds with an epoxycyclohexyl ring). Because of its fast curing rate, it is possible to reduce the amount of acid generator added or use a weak acid generator. Reducing the amount of acid generator can result in acidic active species remaining even after UV irradiation, which is important for preventing metal corrosion. Because of its fast curing rate, thick film curing is possible. Curing by UV irradiation can be applied to materials (equipment) that are sensitive to heat.

[0138] Thermosetting and photocurable materials using the coating-forming composition of the present invention are characterized by rapid curing, transparency, and little shrinkage on cure, and can be used for coating and bonding electronic components, optical components (anti-reflective coatings), and precision mechanical components.

[0139] The film-forming composition (varnish) can be suitably used as a hard coating agent or a composition for nanoimprints.

[0140] The varnish using the metal oxide particles (C) of the present invention may contain the following phosphate ester compound depending on the application.

[0141]

[0142] (In formulas (4) to (6), X １ , X ２ , and X ３ each represents an alkylene group having 2 to 20 carbon atoms; f, h, and j each represent an integer of 1 to 100; e, g, and i each represent an integer of 1 to 3; Y １ , Y ２ , and Y ３ and each represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a (meth)acrylic group. At least one phosphate ester selected from the group consisting of: a polyoxyethylene alkyl (C6-20) ether phosphate ester having an alkyl group having 6 to 20 carbon atoms can be used.

[0143] The phosphate ester can preferably be a polyoxyethylene alkyl ether phosphate ester, and the phosphate ester can be a phosphate ester in which the terminal alkyl group (Y1) of the formula (4) has 6 to 10 or 12 to 15 carbon atoms. For example, products such as Phosphanol RA-600 and RS-610, manufactured by Toho Chemical Industry Co., Ltd., can be used.

[0144] The varnish using the metal oxide particles (C) of the present invention can contain at least one surfactant selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants, silicone surfactants, and nonionic surfactants.

[0145] Examples of anionic surfactants that can be used in the present invention include sodium and potassium salts of fatty acids, alkylbenzenesulfonates, higher alcohol sulfates, polyoxyethylene alkyl ether sulfates, α-sulfofatty acid esters, α-olefinsulfonates, monoalkyl phosphates, and alkanesulfonates.

[0146] For example, alkylbenzene sulfonates include sodium salts, potassium salts and lithium salts, such as sodium C10-C16 alkylbenzene sulfonate, C10-C16 alkylbenzene sulfonic acid, and sodium alkylnaphthalene sulfonate.

[0147] Examples of higher alcohol sulfates include sodium dodecyl sulfate (sodium lauryl sulfate) having 12 carbon atoms, triethanolamine lauryl sulfate, and triethanolammonium lauryl sulfate.

[0148] Polyoxyethylene alkyl ether sulfates include sodium polyoxyethylene styrenated phenyl ether sulfate, ammonium polyoxyethylene styrenated phenyl ether sulfate, sodium polyoxyethylene decyl ether sulfate, ammonium polyoxyethylene decyl ether sulfate, sodium polyoxyethylene lauryl ether sulfate, ammonium polyoxyethylene lauryl ether sulfate, sodium polyoxyethylene tridecyl ether sulfate, sodium polyoxyethylene oleyl cetyl ether sulfate, etc. α-olefin sulfonates include sodium α-olefin sulfonate, etc.

[0149] Examples of alkanesulfonates include sodium 2-ethylhexyl sulfate, etc. Examples of cationic surfactants that can be used in the present invention include alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, and amine salt-based agents.

[0150] Alkyltrimethylammonium salts are quaternary ammonium salts that have a chloride ion or a bromide ion as a counter ion, such as dodecyltrimethylammonium chloride, cetyltrimethylammonium chloride, coconut alkyltrimethylammonium chloride, and alkyl(C16-18)trimethylammonium chloride.

[0151] Dialkyldimethylammonium salts have two lipophilic main chains and two methyl groups, and examples thereof include bis(hydrogenated tallow)dimethylammonium chloride, didecyldimethylammonium chloride, dicoconut alkyldimethylammonium chloride, dihydrogenated tallow alkyldimethylammonium chloride, and dialkyl(C14-18)dimethylammonium chloride.

[0152] Alkyldimethylbenzylammonium salts are quaternary ammonium salts having one lipophilic main chain, two methyl groups, and a benzyl group, such as benzauconium chloride. Examples include alkyl(C8-18)dimethylbenzylammonium chloride. Amine salts are those in which the hydrogen atoms of ammonia have been substituted with one or more hydrocarbon groups, such as N-methylbishydroxyethylamine fatty acid ester hydrochloride.

[0153] Examples of amphoteric surfactants that can be used in the present invention include N-alkyl-β-alanine-type alkylamino fatty acid salts, alkylcarboxybetaine-type alkylbetaines, and N,N-dimethyldodecylamine oxide-type alkylamine oxides, such as lauryl betaine, stearyl betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, and lauryldimethylamine oxide.

[0154] The silicone surfactant used in the present invention is a compound having a repeating unit containing a siloxane bond in the main chain. The weight-average molecular weight of the silicone surfactant can be in the range of 500 to 50,000. These may be modified silicone surfactants, and examples of such surfactants include those having an organic group introduced into the side chain and / or terminal of a polysiloxane. Examples of the organic group include an amino group, an epoxy group, an alicyclic epoxy group, a carbinol group, a mercapto group, a carboxyl group, an aliphatic ester group, an aliphatic amide group, and a polyether group.

[0155] Examples of silicone surfactants include Toray Silicone DC3PA, Toray Silicone SH7PA, Toray Silicone DC11PA, Toray Silicone SH21PA, Toray Silicone SH28PA, Toray Silicone SH29PA, Toray Silicone SH30PA, and Toray Silicone SH8400 (all manufactured by Toray Dow Corning Co., Ltd.), Silwet Examples of such silicone rubbers include L-77, L-7280, L-7001, L-7002, L-7200, L-7210, L-7220, L-7230, L7500, L-7600, L-7602, L-7604, L-7605, L-7622, ​​L-7657, L-8500, and L-8610 (manufactured by Momentive Performance Materials), KP-341, KF-6001, and KF-6002 (manufactured by Shin-Etsu Silicones Co., Ltd.), and BYK307, BYK323, and BYK330 (manufactured by BYK-Chemie).

[0156] The nonionic surfactant used in the present invention is selected from polyoxyethylene alkyl ethers, polyoxyethylene alkylphenol ethers, alkyl glucosides, polyoxyethylene fatty acid esters, sucrose fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and fatty acid alkanolamides. Examples of polyoxyethylene alkyl ethers include polyoxyethylene dodecyl ether (polyoxyethylene lauryl ether), polyoxyalkylene lauryl ether, polyoxyethylene tridecyl ether, polyoxyalkylene tridecyl ether, polyoxyethylene myristyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, polyoxyethylene behenyl ether, polyoxyethylene-2-ethylhexyl ether, and polyoxyethylene isodecyl ether.

[0157] Examples of polyoxyethylene alkylphenol ethers include polyoxyethylene styrenated phenyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene distyrenated phenyl ether, and polyoxyethylene tribenzyl phenyl ether.

[0158] Alkyl glucosides include decyl glucoside and lauryl glucoside.

[0159] Examples of polyoxyethylene fatty acid esters include polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyethylene monooleate, polyethylene glycol distearate, polyethylene glycol dioleate, and polypropylene glycol dioleate.

[0160] Examples of sorbitan fatty acid esters include sorbitan monocaprylate, sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, sorbitan distearate, sorbitan tristearate, sorbitan monooleate, sorbitan trioleate, sorbitan monosesquioleate, and ethylene oxide adducts thereof.

[0161] Examples of polyoxyethylene sorbitan fatty acid esters include polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan triisostearate.

[0162] Furthermore, examples of fatty acid alkanolamides include coconut oil fatty acid diethanolamide, beef tallow fatty acid diethanolamide, lauric acid diethanolamide, and oleic acid diethanolamide.

[0163] Further examples include polyoxyalkyl ethers or polyoxyalkyl glycols such as polyoxyethylene polyoxypropylene glycol and polyoxyethylene fatty acid esters, polyoxyethylene hydrogenated castor oil ether, sorbitan fatty acid ester alkyl ether, alkyl polyglucoside, sorbitan monooleate, and sucrose fatty acid ester.

[0164] Other applications include the use of this material in bonding mobile phone and camera lenses, optical elements such as light-emitting diodes (LEDs) and semiconductor lasers (LDs), liquid crystal panels, biochips, camera lenses and prisms, magnetic components in hard disks of computers and other devices, pickups in CD and DVD players (the part that captures the optical information reflected from the disc), speaker cones and coils, motor magnets, circuit boards, electronic components, and internal engine components of automobiles and the like.

[0165] As a hard coating material for surface protection of automobile bodies, lamps, electrical appliances, building materials, plastics, etc., it can be applied to, for example, automobile and motorcycle bodies, headlight lenses and mirrors, plastic lenses for eyeglasses, mobile phones, game consoles, optical films, ID cards, etc.

[0166] Examples of ink materials for printing on metals such as aluminum and plastics include inks for printing on cards such as credit cards and membership cards, switches on electrical appliances and office equipment, and keyboards, as well as inks for inkjet printers for CDs, DVDs, etc.

[0167] Examples of applications include technology that can be used in combination with 3D CAD to harden resin and create complex three-dimensional objects, photolithography for producing models of industrial products, coating of optical fibers, adhesives, optical waveguides, thick-film resists, etc.

[0168] The film-forming composition of the present invention can also be suitably used as an insulating resin for electronic materials such as anti-reflection films, semiconductor encapsulation materials, adhesives for electronic materials, printed wiring board materials, interlayer insulating film materials, and encapsulants for power modules, as well as an insulating resin for use in high-voltage equipment such as generator coils, transformer coils, and gas-insulated switchgears.

[0169] [Total Metal Oxide Concentration] A sol containing metal oxide particles (C) was weighed using a crucible and pre-dried by heating at 110°C for 30 minutes to remove the solvent. This was then fired at 600°C for 30 minutes. The crucible was weighed, and the total metal oxide concentration was calculated from the weight of the residue. [Average Particle Diameter by Dynamic Light Scattering (Dynamic Light Scattering Particle Diameter)] A sol containing metal oxide particles (C) was diluted with a dispersion solvent, and the solvent parameters were used to measure the particle diameter with a dynamic light scattering measuring device (manufactured by Malvern Instruments Ltd, trade name: Zetasizer). The average particle diameter by dynamic light scattering was measured as the Z-average particle diameter.

[0170] [Evaluation of Light Fastness of Dispersion Liquid] A dispersion of metal oxide particles (C) containing 0.5% by mass of solids in a liquid consisting of water and methanol in a 1:1 mass ratio and a solution of a dye (Sunset Yellow) contained in glycerin at a 0.02% by mass ratio were mixed in a mass ratio of 1:3 to prepare a sample. This was placed in a quartz cell having a length of 1 mm, a width of 1 cm, and a height of 5 cm and sealed. After that, the sample was irradiated with light at an intensity of 0.4 mW / cm using an ultraviolet lamp (SLUV-6 manufactured by AS ONE) with a wavelength range of I-rays (wavelength 365 nm) selected. ２ The film was irradiated with ultraviolet light (wavelength: 365 nm) for 180 minutes.

[0171] On the other hand, the absorbance (A) of the sample at a wavelength of 490 nm before and after ultraviolet irradiation was ０ and A １８０ ) was measured using an ultraviolet-visible spectrophotometer (Shimadzu Corporation, trade name UV-3600), and the fading rate of the dye was calculated using the following formula: ０ ) indicates the absorbance at a wavelength of 490 nm before irradiation with I-rays (wavelength 365 nm), and (A １８０ ) indicates the absorbance at a wavelength of 490 nm after irradiating with I-rays (wavelength 365 nm) for 180 minutes. １８０ ) / (A ０ )) x 100 Furthermore, the photocatalytic activity of the particles was evaluated based on the following criteria. The lower the fading change rate of the particles, the more suppressed the photocatalytic activity. Level A: Fading change rate less than 5% Level B: Fading change rate 5% or more but less than 20% Level C: Fading change rate 20% or more

[0172] [Electrochemical Evaluation] (Positive Electrode Fabrication Method) A positive electrode-forming composition comprising a binder and metal oxide particles (C) coated with conductive carbon was obtained, in which the metal oxide particles (C) accounted for 85% by mass. The positive electrode fabrication method was as follows. 1.0 g of water was added to 0.0295 g of carboxymethyl cellulose (product name: CELLOGEN HE-1500F, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) as a binder (binding agent), and the mixture was kneaded with a mortar and pestle. Next, 0.5000 g of the positive electrode active material (D1) obtained in Example 1 was added, and then 0.5 g of water was added and the mixture was kneaded with a mortar and pestle. After confirming that the mixture was homogeneous, 0.0588 g of acetylene black (manufactured by Strem Chemicals Inc., model number 06-0025, particle size 0.042 μm, purity ≧ 99.99%) was added as a conductive agent (conductive carbon), and 0.5 g of water was added. The binder, conductive carbon, and positive electrode active material (D1) were mixed using a mortar and pestle to obtain a slurry of the electrode-forming composition. This slurry was applied to a 10 μm thick copper foil (manufactured by Furukawa Electric Co., Ltd.) that had been dried at 80 ° C. for 30 minutes to a thickness of 200 μm. After pre-drying at 80 ° C. for 30 minutes, the foil was removed with an area of ​​13 mmφ and dried under reduced pressure at 120 ° C. for 12 hours to obtain a positive electrode (E1). Positive electrodes (E2) to (E6) were prepared in the same manner using the powders (D2) to (D6) of the composite oxide particles obtained in Examples 2 to 3 and Comparative Examples 1 to 3. The mass of the positive electrode excluding the copper foil was 5 mg to 10 mg.

[0173] (Method of Preparing Electrochemical Cell) The electrochemical cell (coin cell) for measurement was prepared in a clean booth with a dew point of −60° C. or less. The electrolyte contained 1M (mol / L) LiPF ６A coin cell was fabricated by sealing the battery case with a 3:7 ethylene carbonate (EC)-ethyl methyl carbonate (EMC) (volume ratio EC:EMC) mixed solution (Kishida Corporation), the cathode prepared as described above, and lithium metal (negative electrode), a separator (Celgard #2400, Asahi Kasei Corporation), a stainless steel battery case and a polypropylene gasket (CR2032, Hosen Corporation), a spacer (SUS, 16 mm diameter x 0.5 mm height, Hosen Corporation), and a wave washer (SUS, 10 mm inner diameter, 2.0 mm height, 0.25 mm thickness, Hosen Corporation) (Figure 1). The amount of electrolyte used was 150 μL, enough to fill the separator.

[0174] (Charge / Discharge Test Method) A charge / discharge test was performed using the prepared electrochemical cell. The charge / discharge test method is as follows. (Charge / Discharge Test) The prepared battery for measuring coverage was left for 24 hours. Next, a charge / discharge test was performed using the prepared electrochemical cell for measurement under the conditions of a lower limit voltage during discharge of 1.4 V, an upper limit voltage during charge of 3.0 V, and a rest time of 5 minutes between charge and discharge. A charge / discharge tester (product name "TOSCAT-3100", manufactured by Toyo Systems Co., Ltd.) was used for the charge / discharge test. The charge / discharge test conditions were as follows: the charge / discharge current density was set to constant current mode, and one charge / discharge was counted as one cycle at room temperature (25°C), and three cycles were repeated. The current density was set to 12 mA / g (g is the mass of titanium oxide in the positive electrode active material) so that the C rate would be C / 10 (1 C = the current value at which full charge or full discharge is achieved in 1 hour) and the theoretical charge capacity of titanium oxide in the voltage range of 1.4 to 3.0 V was set to 120 mAh / g.

[0175] (Confirmation of Charge-Discharge Test Results) FIGS. 2 to 4 show charge-discharge curves up to the third cycle when the positive electrode active materials obtained in Examples 1 to 3 were used, and FIGS. 5 to 7 show charge-discharge curves up to the third cycle when the positive electrode active materials obtained in Comparative Examples 1 to 3 were used. The vertical axis of the charge-discharge curves in FIGS. 2 to 7 represents voltage (V), and the horizontal axis represents capacity (mAh / g (g is the mass of titanium oxide in the positive electrode active material)). (Method of Calculating Coverage Rate) (Coverage rate of metal oxide particles (C) in which core metal oxide particles (A) are coated with coating material (B)%) = 100 - [(average value (mAh / g) of three charge capacities for each sample according to the above measurement method) / (theoretical charge capacity of titanium oxide particles (mAh / g))] × 100. Here, the charge capacity refers to the capacity when the upper limit voltage of 3.0 V is reached, and the theoretical charge capacity of titanium oxide is 120 (mAh / g).

[0176] Reference Example 1: Preparation of titanium oxide-stannic oxide composite oxide colloidal particles (A1) as cores 333.7 g of a 35 mass % aqueous solution of tetraethylammonium hydroxide was dissolved in 255.7 g of pure water, and then 10.1 g of metastannic acid (SnO ２ 8.6 g in terms of tungsten), titanium tetraisopropoxide 324.9 g (TiO ２ To the mixture, 75.0 g of oxalic acid dihydrate (containing 91.3 g in terms of oxalic acid equivalent) and 75.0 g of oxalic acid dihydrate (53.5 g in terms of oxalic acid equivalent) were added under stirring. The mixed solution was maintained at 80°C for 2 hours, and further reduced in pressure to 580 Torr and maintained for 2 hours to prepare a mixed solution. The mixed solution was placed in a glass-lined autoclave vessel, subjected to hydrothermal treatment at 140°C for 5 hours, cooled to room temperature, and then removed. The obtained sol was desalted and washed by ultrafiltration, and after adding 2.5 g of 35% tetraethylammonium hydroxide, the solution was passed through a column packed with 500 ml of ion exchange resin (Amberlite (trade name) IRA-410, manufactured by Organo Corporation). After passing the solution through the column, the sol was an aqueous dispersion sol of alkaline titanium oxide-stannic oxide composite oxide colloidal particles (A1), had a pH of 11.2, a total metal oxide concentration (TiO ２ , and SnO ２ The sol was dried at 110°C and the powder was subjected to X-ray diffraction analysis, which confirmed that the powder was a rutile crystal.

[0177] Reference Example 2: Preparation of titanium oxide-stannic oxide composite oxide colloidal particles (A2) as cores 333.7 g of a 35 mass % aqueous solution of tetraethylammonium hydroxide was dissolved in 331.9 g of pure water, and then 20.3 g of metastannic acid (SnO ２ 17.3 g in terms of titanium tetraisopropoxide, 324.9 g (TiO ２ To the resulting mixture, 75.0 g of oxalic acid dihydrate (containing 91.3 g in terms of oxalic acid equivalent) and 75.0 g of oxalic acid dihydrate (53.5 g in terms of oxalic acid equivalent) were added under stirring. The mixed solution was maintained at 80°C for 2 hours, and then the pressure was reduced to 580 Torr and maintained for 2 hours to prepare a mixed solution. The mixed solution was placed in a glass-lined autoclave vessel, subjected to hydrothermal treatment at 140°C for 5 hours, cooled to room temperature, and then removed. The resulting sol was desalted and washed by ultrafiltration, and after adding 3.1 g of 35% tetraethylammonium hydroxide, the solution was passed through a column packed with 500 ml of ion exchange resin (Amberlite (trade name) IRA-410, manufactured by Organo Corporation). The sol after passing through was an aqueous dispersion sol of alkaline titanium oxide-stannic oxide composite oxide colloidal particles (A2), had a pH of 11.5, a total metal oxide concentration (TiO ２ , and SnO ２ The sol was dried at 110°C and the powder was subjected to X-ray diffraction analysis, which confirmed that the sol was a rutile crystal.

[0178] (Reference Example 3): Preparation of silicon dioxide-stannic oxide composite oxide colloidal particles (B1) to be coated. ２ 77.2 g of sodium stannate (containing 29.8% by mass of sodium stannate in terms of sodium stannate content) was dissolved in 668.8 g of pure water, and then sodium stannate NaSnO ３ ・H ２ O(SnO ２Into the aqueous solution was dissolved 20.9 g of silicon dioxide-stannic oxide composite oxide colloidal particles (B1), which contained 55.1% by mass of silicon dioxide in terms of carbon black. The resulting aqueous solution was passed through a column packed with a hydrogen-type cation exchange resin (Amberlite (trade name) IR-120B). Next, 7.2 g of diisopropylamine was added to the resulting aqueous dispersion sol. The resulting sol was an aqueous dispersion sol of alkaline silicon dioxide-stannic oxide composite oxide colloidal particles (B1), and had a pH of 8.0 and a total metal oxide concentration (SiO ２ , and SnO ２ ) 1.7% by mass, and the primary particle diameter was 1 to 4 nm when observed with a transmission electron microscope.

[0179] (Production Example 1): Preparation of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C1) modified with silicon dioxide-stannic oxide composite oxide Zirconium oxychloride (ZrO ２ 82.7 g of a zirconium oxychloride solution (containing 21.2% by mass in terms of ZrO) was diluted with 501.1 g of pure water to obtain 583.8 g of an aqueous solution of zirconium oxychloride (ZrO ２ A 100.0 g aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (A1) prepared in Reference Example 1 was prepared, and 1750.0 g of the aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (A1) prepared in Reference Example 1 was added thereto under stirring. Hydrolysis was then carried out by heating at 95°C for 5 hours, yielding an aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles having a thin film layer of zirconium oxide formed on the surface thereof. 2330.0 g of the obtained aqueous dispersion sol was added under stirring to 2470.8 g of the alkaline aqueous dispersion sol of silicon dioxide-stannic oxide composite oxide colloidal particles (B1) prepared in Reference Example 3, and the mixture was passed through a column packed with 500 ml of anion exchange resin (Amberlite (trade name) IRA-410, manufactured by Organo Corporation).

[0180] Next, the water-dispersed sol after passing through was heated at 150°C for 4 hours, and then passed through a column packed with a cation exchange resin (Amberlite (trade name) IR-120B, manufactured by Organo Corporation). The solid content of the coating sol added to the container was 40 parts by mass relative to 100 parts by mass of the solid content of the core sol filled in the container, and the addition was carried out over 1 minute at a rate of 40 parts by mass per minute. 3.5 g of tri-n-pentylamine was added to the obtained water-dispersed sol, and the mixture was concentrated by an ultrafiltration membrane method to obtain a water-dispersed sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C1) modified with silicon dioxide-stannic oxide composite oxide. This water-dispersed sol had a pH of 5.2, a total metal oxide content (TiO ２ , ZrO ２ , SnO ２ , and SiO ２ The concentration was 30.5% by mass, the viscosity was 5.0 mPa·s, and the average particle size measured by dynamic light scattering (DLS) (dynamic light scattering particle size) was 20 nm.

[0181] (Production Example 2): Preparation of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C2) modified with silicon dioxide-stannic oxide composite oxide Zirconium oxychloride (ZrO ２ 82.7 g of a zirconium oxychloride solution (containing 21.2% by mass in terms of ZrO) was diluted with 501.1 g of pure water to obtain 583.8 g of an aqueous solution of zirconium oxychloride (ZrO ２ A 1000.0 g aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (A2) prepared in Reference Example 2 was prepared, and 1750.0 g of the aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (A2) prepared in Reference Example 2 was added thereto under stirring. Hydrolysis was then carried out by heating at 95°C for 5 hours, yielding an aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles having a thin film layer of zirconium oxide formed on the surface thereof. 2330.0 g of the obtained aqueous dispersion sol was added under stirring to 1852.9 g of the aqueous dispersion sol of alkaline silicon dioxide-stannic oxide composite oxide colloidal particles (B1) prepared in Reference Example 3, and the mixture was passed through a column packed with 500 ml of anion exchange resin (Amberlite (trade name) IRA-410, manufactured by Organo Corporation).

[0182] Next, the water-dispersed sol after passing through was heated at 150°C for 4 hours, and then passed through a column packed with a cation exchange resin (Amberlite (trade name) IR-120B, manufactured by Organo Corporation). The solid content of the coating sol added to the container was 30 parts by mass relative to 100 parts by mass of the solid content of the core sol filled in the container, and the addition was carried out over 1 minute at a rate of 30 parts by mass per minute. 3.5 g of tri-n-pentylamine was added to the obtained water-dispersed sol, and the mixture was concentrated by an ultrafiltration membrane method to obtain a water-dispersed sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C2) modified with silicon dioxide-stannic oxide composite oxide. This water-dispersed sol had a pH of 5.2, a total metal oxide content (TiO ２ , ZrO ２ , SnO ２ , and SiO ２ The concentration was 30.5% by mass, the viscosity was 5.0 mPa·s, and the average particle size measured by dynamic light scattering (DLS) (dynamic light scattering particle size) was 20 nm.

[0183] (Production Example 3): Step of Surface-Modifying Titanium Oxide-Stannic Oxide-Zirconium Oxide Composite Oxide Colloid Particles Modified with Silicon Dioxide-Stannic Oxide Composite Oxide 100 g of the aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloid particles (C2) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 2 was subjected to a rotary evaporator to replace the dispersion medium with methanol, thereby obtaining a methanol-dispersed sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloid particles (C2) modified with silicon dioxide-stannic oxide composite oxide. 2.5 g of KBE-585A (manufactured by Shin-Etsu Chemical Co., Ltd.) as a surface modifier was added to the obtained sol under stirring, and the particles were surface-modified by heating under reflux at 65°C for 5 hours. This surface-modified methanol-dispersed sol contained a total of 100 g of titanium oxide-stannic oxide composite oxide colloid particles (C2) modified with silicon dioxide-stannic oxide composite oxide. ２ , ZrO ２ , SnO ２ , and SiO ２ The concentration of the granules was 30.5% by mass, and the average particle size measured by dynamic light scattering (DLS) (dynamic light scattering particle size) was 20 nm.

[0184] (Production Example 4): Preparation of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C3) Zirconium oxychloride (ZrO ２ 82.7 g of a zirconium oxychloride solution (containing 21.2% by mass in terms of ZrO) was diluted with 501.1 g of pure water to obtain 583.8 g of an aqueous solution of zirconium oxychloride (ZrO ２ To this was added, under stirring, 1,750.0 g of the aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (A2) prepared in Reference Example 2. Next, hydrolysis was carried out by heating at 95°C for 5 hours, to obtain an aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles having a thin film layer of zirconium oxide formed on the surface thereof.

[0185] (Production Example 5): Preparation of titanium oxide-stannic oxide composite oxide colloidal particles (C4) modified with silicon dioxide-stannic oxide composite oxide. 1,750.0 g of the aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (A1) prepared in Reference Example 1 was added with stirring to 772.1 g of the aqueous dispersion sol of alkaline silicon dioxide-stannic oxide composite oxide colloidal particles (B1) prepared in Reference Example 3. The mixture was heated at 95°C for 5 hours and then passed through a column packed with a cation exchange resin (Amberlite (trade name) IR-120B, manufactured by Organo Corporation). 3.5 g of tri-n-pentylamine was added to the obtained aqueous dispersion sol, and the mixture was concentrated by ultrafiltration to obtain an aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (C4) modified with silicon dioxide-stannic oxide composite oxide. This aqueous dispersion sol had a pH of 5.2, a total metal oxide (TiO ２ , ZrO ２ , SnO ２ , and SiO ２ The concentration was 30.5% by mass, the viscosity was 5.0 mPa·s, and the average particle size measured by dynamic light scattering (DLS) (dynamic light scattering particle size) was 20 nm.

[0186] (Production Example 6): Preparation of titanium oxide-stannic oxide composite oxide colloidal particles (C5) modified with silicon dioxide-stannic oxide composite oxide. 1750.0 g of the aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (A1) prepared in Reference Example 1 was added with stirring to 1544.1 g of the aqueous dispersion sol of alkaline silicon dioxide-stannic oxide composite oxide colloidal particles (B1) prepared in Reference Example 3. The mixture was heated at 95°C for 5 hours and then passed through a column packed with a cation exchange resin (Amberlite (trade name) IR-120B, manufactured by Organo Corporation). 3.5 g of tri-n-pentylamine was added to the obtained aqueous dispersion sol, and the mixture was concentrated by ultrafiltration to obtain an aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (C5) modified with silicon dioxide-stannic oxide composite oxide. This aqueous dispersion sol had a pH of 5.2, a total metal oxide (TiO ２ , ZrO ２ , SnO ２ , and SiO ２ The concentration was 30.5% by mass, the viscosity was 5.0 mPa·s, and the average particle size measured by dynamic light scattering (DLS) (dynamic light scattering particle size) was 20 nm.

[0187] Example 1 The light resistance of the dispersion was evaluated using an aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C1) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 1. Next, 10 g of the aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C1) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 1 was dried at 100°C to prepare a positive electrode active material (D1), and the coverage was evaluated. In FIG. 2 , which shows the results of the charge-discharge test, the average charge capacity after three charge-discharge cycles was 4.56 (mAh / g), indicating a coverage of 96.2%. Furthermore, the light resistance of the dispersion was "Level A."

[0188] Example 2 The light resistance of the dispersion was evaluated using an aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C2) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 2. Next, 10 g of the aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C2) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 2 was dried at 100°C to prepare a positive electrode active material (D2), and the coverage was evaluated. In FIG. 3 , which shows the results of the charge-discharge test, the average charge capacity after three charge-discharge cycles was 27.7 (mAh / g), indicating a coverage of 76.9%. Furthermore, the light resistance of the dispersion was "Level B."

[0189] Example 3 The light resistance of the dispersion was evaluated using an aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C2) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 3. Next, 10 g of the aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide colloidal particles (C2) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 3 was dried at 100°C to prepare a positive electrode active material (D3), and the coverage was evaluated. In FIG. 4 , which shows the results of the charge-discharge test, the average charge capacity after three charge-discharge cycles was 21.7 (mAh / g), indicating a coverage of 81.9%. The light resistance of the dispersion was also evaluated as "Level B."

[0190] Comparative Example 1 The aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide (C3) obtained in Production Example 4 was used to evaluate the light resistance of the dispersion. Next, 10 g of the aqueous dispersion sol of titanium oxide-stannic oxide-zirconium oxide composite oxide (C3) obtained in Production Example 4 was passed through a column packed with 50 milliliters of anion exchange resin (Amberlite (trade name) IRA-410, manufactured by Organo Corporation), and the sol after passing through was dried at 100°C to prepare a positive electrode active material (D4), and the coverage was evaluated. In FIG. 5 , which shows the results of the charge-discharge test, the average charge capacity after three charge-discharge cycles was 62.5 (mAh / g), indicating a coverage of 47.9%. The light resistance of the dispersion was "Level C."

[0191] Comparative Example 2 The light resistance of the dispersion was evaluated using an aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (C4) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 5. Next, 10 g of the aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (C4) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 5 was dried at 100°C to prepare a positive electrode active material (D5), and the coverage was evaluated. In FIG. 6 , which shows the results of the charge-discharge test, the average charge capacity after three charge-discharge cycles was 81.1 (mAh / g), indicating a coverage of 32.4%. The light resistance of the dispersion was "Level C."

[0192] Comparative Example 3 The light resistance of the dispersion was evaluated using an aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (C5) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 6. Next, 10 g of the aqueous dispersion sol of titanium oxide-stannic oxide composite oxide colloidal particles (C5) modified with silicon dioxide-stannic oxide composite oxide obtained in Production Example 6 was dried at 100°C to prepare a positive electrode active material (D6), and the coverage was evaluated. In FIG. 7 , which shows the results of the charge-discharge test, the average charge capacity after three charge-discharge cycles was 64.8 (mAh / g), indicating a coverage of 46.0%. The light resistance of the dispersion was "Level C."

[0193] In the present invention, focusing on the fact that rutile-type titanium oxide can electrochemically insert and release lithium ions and that the coverage rate is inversely proportional to the charge capacity that is generated as lithium ions are released, an electrochemical cell is produced from a positive electrode material containing the above-mentioned metal oxide particles (C) and a negative electrode material made of lithium foil, and the charge capacity is measured. From these values, it is possible to measure the coverage rate of metal oxide particles (C) in which the surface of metal oxide particles (A) containing titanium oxide as cores is coated with coating material (B).

[0194] It was confirmed that Examples 1 to 3, which used titanium oxide-based core-shell particles having a zirconium oxide intermediate layer and a silicon dioxide-stannic oxide composite oxide coating, had a higher coverage rate than Examples 4 to 6. Among these, the titanium oxide-based core-shell particles of Example 1 in particular had an extremely high coverage rate of 96.2% and exhibited extremely good light resistance.

[0195] According to the present invention, it is possible to provide core-shell type metal oxide particles (C) in which the surfaces of metal oxide particles (A) containing titanium oxide as cores (nuclei) are coated with a coating material (B) that forms a shell, and the particles (C) in which the particles (A) are coated with the coating material (B) have a high coverage of 50 to 100%. Furthermore, since the coverage can be measured by an electrochemical method, the present invention has industrial applicability.

[0196] 1. Electrochemical cell, 2. Battery case, 3. Gasket, 4. Anode, 5. Separator, 6. Cathode, 7. Spacer, 8. Wave washer, 9. Cap

Claims

1. A method for measuring a coverage of metal oxide particles (C) in which the surfaces of titanium oxide-containing core metal oxide particles (A) are covered with a coating (B), the method comprising the steps of: (I) applying an electrode-forming composition, which is made of a binder, conductive carbon, and metal oxide particles (C) and contains 85% by mass of the metal oxide particles (C) to a thickness of 200 μm on copper foil, drying the composition, and extracting a film having an area of ​​13 mmφ to form a positive electrode and a lithium foil having an area of ​​13 mmφ to form a negative electrode, and combining these to form an electrochemical cell; and (II) repeating three cycles of charge and discharge in the range of 1.4 to 3.0 V and measuring the average charge capacity (mAh / g) of the three charge and discharge cycles, in which the coverage is calculated using the following formula, where the theoretical charge capacity of titanium oxide is 120 (mAh / g): coverage (%)=100-(average charge capacity / theoretical charge capacity)×100.

2. Metal oxide particles (C) in which the surface of metal oxide particles (A) containing titanium oxide as a core is coated with a coating material (B), and the coating rate of metal oxide particles (C) in which metal oxide particles (A) are coated with coating material (B) is 50 to 100% as the coating rate measured by the measurement method of claim 1.

3. Metal oxide particles (C) according to claim 2, having a coverage of 90 to 100%.

4. Metal oxide particles (C) according to claim 2, having a titanium oxide content of 50 mol % or more.

5. Metal oxide particles (C) according to any one of claims 2 to 4, wherein the metal oxide particles (A) are either titanium oxide particles (A1) or metal oxide particles (A2) which are a combination of titanium oxide and at least one metal oxide selected from the group consisting of tin oxide, zirconium oxide, silicon dioxide, zinc oxide, antimony oxide, niobium oxide, iron oxide, and tungsten oxide.

6. Metal oxide particles (C) according to any one of claims 2 to 5, wherein the coating (B) is at least one coating (B) selected from the group consisting of electrochemically inactive metal oxide particles (B1), amines (B2), silane coupling agents (B3), and organic acids and organic acid esters (B4).

7. Metal oxide particles (C) according to claim 6, wherein the electrochemically inactive metal oxide particles (B1) are metal oxide particles (B1) that are electrochemically inactive in the range of 1.4 to 3.0 V in the measurement.

8. Metal oxide particles (C) according to claim 6, wherein the electrochemically inactive metal oxide particles (B1) are metal oxides (B1) consisting of a combination of at least one metal oxide selected from the group consisting of tin oxide, zirconium oxide, silicon dioxide, zinc oxide, antimony oxide, niobium oxide, iron oxide, and tungsten oxide.

9. The metal oxide particles (C) according to claim 6, wherein the amine (B2) is a secondary or tertiary amine having a total of 5 to 35 carbon atoms.

10. The silane coupling agent (B3) is (In formula (1), R １ each represents an alkyl group, a halogenated alkyl group, an alkenyl group, an aryl group, or an organic group having a polyether group, an epoxy group, a (meth)acryloyl group, a mercapto group, an amino group, a ureido group, an acid anhydride group, or a cyano group, and is bonded to a silicon atom by a Si—C bond; R ２ each represents an alkoxy group, an acyloxy group, or a halogen group, a represents an integer of 1 to 3, and in formula (2) and formula (3), R ３ and R ５ are each an alkyl group having 1 to 3 carbon atoms or an aryl group having 6 to 30 carbon atoms and bonded to a silicon atom by a Si—C bond, R ４ and R ６ each represents an alkoxy group, an acyloxy group, or a halogen group, Y represents an alkylene group, an NH group, or an oxygen atom, b is an integer of 1 to 3, c is an integer of 0 or 1, and d is an integer of 1 to 3.

11. Metal oxide particles (C) according to claim 6, wherein the organic acid and organic acid ester (B4) is acetic acid, benzoic acid, or an alkyl, aryl, or arylalkyl ester thereof.

12. Metal oxide particles (C) according to any one of claims 2 to 9, wherein a dispersion of metal oxide particles (C) containing 0.5% by mass of solids in a liquid consisting of water and methanol in a 1:1 mass ratio, and a solution of a dye (sunset yellow) containing 0.02% by mass in glycerin are mixed in a mass ratio of 1:3, and the mixture is irradiated with ultraviolet light having a wavelength of 365 nm at an intensity of 0.4 mW / cm ２ The metal oxide particles (C) have a discoloration rate of 20% or less of the dye in the mixture after irradiation with 400 nm for 180 minutes.

13. A metal oxide sol comprising the metal oxide particles (C) according to any one of claims 2 to 12.

14. The metal oxide sol according to claim 13, wherein the dispersion medium of the metal oxide sol is water, an alcohol, an ester, a ketone, an amide, or a hydrocarbon.

15. A varnish comprising the metal oxide particles (C) according to any one of claims 2 to 12 or the metal oxide sol according to any one of claims 13 to 14, and a thermosetting or photosetting resin.

16. The varnish according to claim 15, wherein the varnish is a varnish for improving lightfastness.

17. The varnish according to claim 15, wherein the varnish is a coating agent for eyeglass lenses.

18. A method for producing metal oxide particles (C) according to any one of claims 2 to 12, characterized in that the coverage is adjusted to 50 to 100% by the measurement method of claim 1.

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