Low dielectric loss tangent, large particle titanium oxide composition

Abstract

To provide a dielectric filler with a large particle size and a low dielectric loss tangent.SOLUTION: A titanium oxide composition comprises particulate oxide that comprises titanium oxide and an oxide of an element selected from the group consisting of Si, Al and W, with a median size of 10-30 μm, and a dielectric loss tangent (tanδ) of 1×10-3 or less within a frequency range of 200 MHz to 100 GHz.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a low dielectric loss tangent, large-particle titanium oxide composition. More specifically, it relates to a low dielectric loss tangent, large-particle titanium oxide composition that can be used as a dielectric filler in high-frequency materials. [Background technology]

[0002] AI / IoT is advancing in global markets, including Japan, with the widespread adoption of communication devices such as smartphones and tablets, IoT home appliances, and manufacturing equipment utilizing AI / IoT technology. This has led to an increase in information transmission using high-frequency signals (above 1 GHz), and further increases are expected with the future operation of autonomous vehicles. In the high-frequency range, transmission loss is greater than at conventional wavelengths, so materials with low dielectric loss tangent are required for efficient transmission of high-frequency signals. However, conventionally used dielectric materials have very high transmission loss in the high-frequency range and cannot be used, so there is a need for dielectric materials with low transmission loss. Patent Document 1 proposes a glass filler in which various inorganic fillers are embedded in glass. Patent Document 2 describes an adhesive structure comprising a dielectric heating sheet containing a thermoplastic resin and a dielectric filler between a pair of adherends, and states that the average particle diameter of the dielectric filler is preferably in the range of 0.1 μm or more and 30 μm or less. Furthermore, Patent Document 3 proposes a resin composition in which dielectric powders such as barium titanate and titanium oxide are added to epoxy resin to adjust the dielectric constant, and Patent Document 4 proposes a particle material made of titanium dioxide with a volume average particle diameter, sphericity, moisture content, and linseed oil absorption within predetermined ranges as a dielectric material. Furthermore, regarding methods for producing titanium dioxide particles, Patent Document 5 reports a method for producing aggregated titanium dioxide particles with apparent particle size of 1 to 20 μm, and Patent Document 6 reports a method for producing spherical large-particle titanium dioxide by generating hydrated titanium dioxide using a predetermined titanyl sulfate aqueous solution as a raw material, and then filtering, washing, and calcining the obtained hydrated titanium dioxide. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-19055 [Patent Document 2] International Publication No. 2019 / 031466 [Patent Document 3] Japanese Patent Publication No. 2020-105523 [Patent Document 4] Japanese Patent Publication No. 2021-127254 [Patent Document 5] Japanese Patent Application Publication No. 17422 / 1983 [Patent Document 6] Japanese Patent Publication No. 2018-154527 [Overview of the project] [Problems that the invention aims to solve]

[0004] As mentioned above, various materials have been proposed for dielectrics, but none have sufficiently low dielectric loss tangents, and there is a need for fillers with even lower dielectric loss tangents. Furthermore, in order to sufficiently reduce signal transmission loss in the high-frequency range, it is important that the material can be incorporated into the resin at high concentrations, and for this purpose, larger particle sizes are required. Patent documents 2 to 4 describe titanium dioxide as a dielectric filler to be added to resins, but there are no examples of titanium dioxide with a particle size of 10 μm or larger being added. Patent documents 5 and 6 describe methods for manufacturing titanium dioxide, but the products manufactured are small in size, and there are no examples of manufacturing titanium dioxide with a particle size of 10 μm or larger. In particular, when injection molding resins, fillers with a large particle size of about 10 to 30 μm are generally used, but dielectric fillers with such large particle sizes and low dielectric loss tangents are not known.

[0005] In view of the above situation, the present invention aims to provide a dielectric filler with a large particle size and a low dielectric loss tangent. [Means for solving the problem]

[0006] The inventors investigated dielectric fillers with large particle size and low dielectric loss tangent, and found that by producing granules containing titanium oxide and elements selected from the group consisting of Si, Al, and W, and / or compounds thereof, and by firing these granules at a temperature of 1050 to 1300°C, a titanium oxide composition with large particle size and low dielectric loss tangent can be obtained, thus completing the present invention.

[0007] In other words, the present invention includes particulate oxides comprising titanium oxide and an oxide of an element selected from the group consisting of Si, Al, and W, with a median diameter of 10 to 30 μm and a dielectric loss tangent (tanδ) of 1 × 10 at frequencies of 200 MHz to 100 GHz. -3 The titanium oxide composition is characterized by the following:

[0008] The above titanium oxide composition preferably has a relative permittivity (ε) of 10 or more at frequencies of 200 MHz to 100 GHz.

[0009] The above titanium oxide composition has a BET specific surface area of ​​0.5 m². 2 It is preferable that the value be less than or equal to / g.

[0010] The above titanium oxide composition preferably contains 0.05 to 10% by weight of an element selected from the group consisting of Si, Al, and W relative to the titanium oxide.

[0011] The present invention also relates to a resin composition characterized by comprising the titanium oxide composition and a resin.

[0012] The present invention also relates to an electronic component material characterized by comprising the resin composition of the present invention, and an electronic component characterized by being manufactured using the electronic component material.

[0013] The present invention further provides a method for producing a titanium oxide composition comprising particulate oxides comprising titanium oxide and an oxide of an element selected from the group consisting of Si, Al, and W, The manufacturing method includes a step of manufacturing a granulated product containing titanium oxide and a simple substance and / or compound of an element selected from the group consisting of Si, Al, and W, and a step of firing the granulated product at a temperature of 1050 to 1300°C. It is also a manufacturing method of a titanium oxide composition characterized by this.

[0014] The step of manufacturing a granulated product containing titanium oxide and a simple substance and / or compound of an element selected from the group consisting of Si, Al, and W is preferably a step of spray granulating titanium oxide or a mixture of titanium oxide and a simple substance and / or compound of an element selected from the group consisting of Si, Al, and W.

Effects of the Invention

[0015] The titanium oxide composition of the present invention is a material with a low dielectric tangent and has a large particle size, so it can be blended into a resin at a high concentration and can be suitably used as a dielectric filler for reducing the dielectric tangent of the resin material.

Brief Description of the Drawings

[0016] [Figure 1] It is a figure showing the SEM observation result of the titanium oxide composition obtained in Example 1. [Figure 2] It is a figure showing the particle size distributions of the titanium oxide composition obtained in Example 1 and the titanium oxides obtained in Comparative Examples 2 and 3.

Modes for Carrying Out the Invention

[0017] Hereinafter, the preferred embodiments of the present invention will be specifically described. However, the present invention is not limited only to the following description and can be appropriately changed and applied within the scope of not changing the gist of the present invention.

[0018] 1. Low Dielectric Tangent, Large Particle Titanium Oxide Composition The titanium oxide composition of the present invention comprises particulate oxides comprising titanium oxide and an oxide of an element selected from the group consisting of Si, Al, and W, with a median diameter of 10 to 30 μm and a dielectric loss tangent (tanδ) of 1 × 10¹⁶ at frequencies of 200 MHz to 100 GHz. -3 The following applies: Particulate oxides comprising titanium dioxide and an oxide of an element selected from the group consisting of Si, Al, and W are not particularly limited in form as long as they contain titanium dioxide and an oxide of an element selected from the group consisting of Si, Al, and W. They may be formed by a uniform or non-uniform mixture of titanium dioxide and an oxide of an element selected from the group consisting of Si, Al, and W, resulting in a particulate shape, or they may be formed by coating particles of one oxide with the other oxide.

[0019] The titanium dioxide composition of the present invention has a median diameter of 10 to 30 μm. This large particle size allows for uniform mixing without particle aggregation when blended with a resin. Therefore, it can be blended at high concentrations into the resin, effectively reducing the dielectric loss tangent of the resin material. The median diameter of the titanium dioxide composition is preferably 10 to 25 μm, more preferably 10 to 22 μm, and even more preferably 10 to 20 μm. The median diameter of the titanium oxide composition can be measured by the method described in the examples below.

[0020] The titanium oxide composition of the present invention has a dielectric loss tangent (tanδ) of 1.0 × 10¹⁶ in the high-frequency region of 200 MHz to 100 GHz. -3 The following is the result. Because the dielectric loss tangent in the high-frequency range is sufficiently low, when incorporated into a resin, it can effectively reduce the dielectric loss tangent of the resin in the high-frequency range. The dielectric loss tangent of the titanium oxide composition in the high-frequency range of 200 MHz to 100 GHz is 9.0 × 10⁻⁶. -4 Preferably, the following: More preferably, 8.0 × 10 -4 The following, and more preferably, 6.0 × 10 -4 The following applies: The dielectric tangent of the titanium oxide composition can be measured by the method described in the examples below.

[0021] The titanium oxide composition of the present invention preferably has a BET specific surface area of 0.5 m 2 / g or less. By having such a BET specific surface area, the oil absorption amount of the resin can be reduced, and the titanium oxide composition can be blended into the resin at a high concentration. The BET specific surface area of the titanium oxide composition is more preferably 0.4 m 2 / g or less, and even more preferably 0.3 m 2 / g or less. The BET specific surface area of the titanium oxide composition can be measured by the method described in the examples below.

[0022] The titanium oxide composition of the present invention preferably has a relative permittivity (ε) of 10 or more at a frequency of 200 MHz to 100 GHz. As described above, since the titanium oxide composition of the present invention can be blended into the resin at a high concentration, if the titanium oxide composition has such a relative permittivity, the relative permittivity of the resin can be controlled by adjusting the blending amount of the titanium oxide composition of the present invention with respect to the resin. The relative permittivity of the titanium oxide composition at a frequency of 200 MHz to 100 GHz is more preferably 12 or more, and even more preferably 15 or more. The relative permittivity of the titanium oxide composition can be measured by the method described in the examples below.

[0023] The titanium oxide composition of the present invention preferably has a weight loss rate of 0.15% or less when heated from room temperature to 200 °C at a rate of 10 °C / min using a thermogravimetric analyzer. With such a weight loss rate, there is less adsorbed water on the surface of the titanium oxide composition, and the dielectric tangent can be lowered. The weight loss rate is more preferably 0.1% or less, and even more preferably 0.05% or less.

[0024] The titanium dioxide composition of the present invention preferably has a (D90-D10) / D50 ratio of 5 or less. This narrow particle size distribution allows for uniform dispersion in the resin. The (D90-D10) / D50 ratio of the titanium dioxide composition is more preferably 4 or less, and even more preferably 1 or less. The (D90-D10) / D50 of the titanium oxide composition can be obtained by measuring D90 and D10 in the same manner as the method for measuring the median diameter D50 described in the examples.

[0025] The above-mentioned particulate oxide may contain titanium dioxide and elements selected from the group consisting of Si, Al, and W, and may contain one of these elements or two or more.

[0026] The titanium oxide composition of the present invention may contain titanium oxide and an oxide of an element selected from the group consisting of Si, Al, and W. The content ratio of the oxide of the element selected from the group consisting of Si, Al, and W is not particularly limited, but it is preferable that the ratio of the element selected from the group consisting of Si, Al, and W contained in the oxide is 0.05 to 10% by weight relative to 100% by weight of titanium oxide contained in the titanium oxide composition. Including the element selected from the group consisting of Si, Al, and W in such a ratio results in a titanium oxide composition with a lower dielectric loss tangent. More preferably, the ratio of the element selected from the group consisting of Si, Al, and W is 0.05 to 8% by weight relative to 100% by weight of titanium oxide contained in the titanium oxide composition, and even more preferably, it is 0.1 to 5% by weight relative to titanium oxide.

[0027] The titanium dioxide contained in the titanium dioxide composition of the present invention may be of the anatase type, the rutile type, or may contain both.

[0028] The titanium oxide composition of the present invention may contain other components as long as it contains particulate oxides comprising titanium oxide and an oxide of an element selected from the group consisting of Si, Al, and W. Examples of other components include titanium oxide, silicon oxide, aluminum oxide, and tungsten oxide. The proportion of other components is preferably 5% by mass or less based on 100% by mass of the entire titanium dioxide composition. More preferably, it is 3% by mass or less, and even more preferably, 1% by mass or less.

[0029] 2. Resin compositions, materials for electronic components, and electronic components As described above, the titanium oxide composition of the present invention can effectively reduce the dielectric loss tangent when blended with a resin. Furthermore, if the relative permittivity of the titanium oxide composition of the present invention is within the range described above, the relative permittivity of the resin can be controlled by adjusting the blending amount. For this reason, the resin composition obtained by blending the titanium oxide composition of the present invention with a resin can be suitably used as a material for electronic components that use signals in the high-frequency range. A resin composition containing the titanium oxide composition and resin of the present invention is also one of the present inventions, and a material for electronic components containing the resin composition, and an electronic component made using the material for electronic components are also one of the present inventions.

[0030] The resin contained in the resin composition of the present invention is not particularly limited as long as it can be incorporated with the titanium oxide composition of the present invention. Examples include epoxy resins, polyethylene, polypropylene, polyester, polyamide, polyimide, silicone resins, phenolic resins, polysulfones, etc., and one or more of these can be used.

[0031] The proportion of resin contained in the resin composition of the present invention is not particularly limited and can be appropriately selected according to the desired application and properties, but it is preferably 10 to 95% by mass based on 100% by mass of the resin composition. More preferably, it is 20 to 90% by mass, and even more preferably, it is 20 to 80% by mass.

[0032] The blending ratio of the titanium oxide composition of the present invention in the resin composition of the present invention is not particularly limited, but it is preferable that it be 5 to 80% by mass of 100% by mass of the resin composition, in order to sufficiently reduce the dielectric loss tangent and adjust the relative permittivity without losing the properties necessary for a resin material such as moldability. More preferably, it is 10 to 80% by mass of the total resin composition, and even more preferably, it is 20 to 80% by mass of the total resin composition.

[0033] The resin composition of the present invention may contain a solvent. The solvent is not particularly limited, but examples include alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate; ethers such as dimethyl ether and diethyl ether; aromatic hydrocarbon solvents such as xylene, toluene, cyclohexylbenzene, dihydrobenzofuran, trimethylbenzene, and tetramethylbenzene; aromatic heterocyclic compound solvents such as pyridine, pyrazine, furan, pyrrole, thiophene, and methylpyrrolidone; and aliphatic hydrocarbon solvents such as hexane, pentane, heptane, and cyclohexane. One or more of these can be used.

[0034] The solvent content in the resin composition of the present invention is not particularly limited, but is preferably 0 to 80% by mass based on 100% by mass of the resin composition. More preferably, it is 0 to 60% by mass, and even more preferably, it is 0 to 50% by mass.

[0035] The resin composition of the present invention may contain other components besides the titanium oxide composition, resin, and solvent of the present invention. Examples of other components include fillers other than the titanium oxide composition of the present invention, viscosity modifiers, defoamers, flame retardants, etc. The resin composition of the present invention may contain one of these other components, or two or more.

[0036] The content of the above-mentioned other components is preferably 10% by mass or less, based on 100% by mass of the resin composition of the present invention. More preferably, it is 5% by mass or less, and even more preferably, 3% by mass or less.

[0037] 3. Method for producing titanium dioxide composition The present invention also relates to a method for producing a titanium oxide composition comprising particulate oxides comprising titanium oxide and an oxide of an element selected from the group consisting of Si, Al, and W, wherein the production method comprises the steps of producing granules comprising titanium oxide and an element selected from the group consisting of Si, Al, and W, and / or compounds thereof, and firing the granules at a temperature of 1050 to 1300°C. Generally, when producing titanium dioxide with large particle sizes, a synthesis method involving high-temperature calcination is known. However, high-temperature calcination of titanium dioxide causes oxygen deficiency and increases the dielectric loss tangent, making it impossible to obtain titanium dioxide with large particle sizes and low dielectric loss tangent. In contrast, by producing the titanium dioxide composition using the method of the present invention, it is possible to obtain the titanium dioxide composition of the present invention, which has large particle sizes and low dielectric loss tangent.

[0038] The process for producing granules containing titanium dioxide and elements selected from the group consisting of Si, Al, and W is not particularly limited in terms of the method, as long as granules containing titanium dioxide and elements selected from the group consisting of Si, Al, and W are produced. The granules containing titanium dioxide and elements and / or compounds selected from the group consisting of Si, Al, and W may be granulated after mixing titanium dioxide with additives consisting of elements and / or compounds selected from the group consisting of Si, Al, and W, or they may be granulated with titanium dioxide and then additives consisting of elements and / or compounds selected from the group consisting of Si, Al, and W.

[0039] When granulation is performed after mixing titanium dioxide with an additive consisting of elements and / or compounds selected from the group consisting of Si, Al, and W in the above granulation process, the method of mixing the titanium dioxide and the additive is not particularly limited as long as the titanium dioxide and the additive are mixed, but a method of repulping the titanium dioxide in a solvent and then adding the additive is preferred. By using this method, the titanium dioxide and the additive can be thoroughly mixed.

[0040] When adding an additive consisting of an element selected from the group consisting of Si, Al, and W, and / or a compound thereof, after granulating titanium dioxide in the above granulation process, the method of adding the additive is not particularly limited, but a method of spraying the additive dissolved or dispersed in a solvent onto the granulated titanium dioxide is preferred. By using this method, the additive can be uniformly added to the entire granulated titanium dioxide. When spraying a mixture of additives dissolved or dispersed in a solvent onto granulated titanium dioxide, the spraying may be performed only once, or the spraying and drying process may be repeated multiple times.

[0041] The titanium dioxide used in the above granulation process may be of the anatase type, the rutile type, or may contain both.

[0042] The median diameter of the titanium oxide used in the granulation process described above is preferably 0.005 to 0.1 μm. More preferably, it is 0.01 to 0.08 μm. By using titanium oxide within this range in the granulation process, the mixing with the additives becomes more uniform, and by calcining the granules, a titanium oxide composition with a lower dielectric loss tangent can be obtained. The median diameter of titanium dioxide can be measured using the same method as the method for measuring the median diameter of the titanium dioxide composition described in the examples below.

[0043] When using a compound of an element selected from the group consisting of Si, Al, and W in the above granulation process, the compound is not particularly limited and includes one or more of oxides, chlorides, hydroxides, carbonates, hydrochlorides, acetates, metal salts, etc.

[0044] The solvent used in the granulation process described above may be one or more alcohols such as water, methanol, ethanol, or propanol. Of these, water is preferred.

[0045] The method for granulating the above-mentioned titanium dioxide, or a mixture of titanium dioxide and elements selected from the group consisting of Si, Al, and W, is not particularly limited, but spray granulation is preferred. By using spray granulation, particles of the size required for dielectric fillers can be efficiently obtained.

[0046] The elemental and / or compound selected from the group consisting of Si, Al, and W may be any elemental and / or compound of Si, Al, or W, and one elemental and / or compound may be used, or two or more elementsal and / or compounds may be used.

[0047] In the process of producing granules of titanium dioxide and elements selected from the group consisting of Si, Al, and W, the amount of elements selected from the group consisting of Si, Al, and W, and / or compounds used is not particularly limited, but it is preferable that the proportion of elements selected from the group consisting of Si, Al, and W contained in the elements selected from the group consisting of Si, Al, and W is 0.05 to 10% by mass relative to 100% by mass of titanium dioxide used. By using them in such proportions, a titanium dioxide composition with a lower dielectric loss tangent can be obtained. The amount of elements selected from the group consisting of Si, Al, and W, and / or compounds used is more preferably such that the proportion of elements selected from the group consisting of Si, Al, and W contained in the elements selected from the group consisting of Si, Al, and W is 0.05 to 8% by mass relative to 100% by mass of titanium dioxide used, and even more preferably such that it is 0.1 to 5% by mass relative to 100% by mass of titanium dioxide used.

[0048] When a slurry containing titanium dioxide, or titanium dioxide and elements selected from the group consisting of Si, Al, and W, is supplied to the granulation process described above, the slurry concentration is preferably 150 to 300 g / L. More preferably 200 to 250 g / L. By performing spray granulation using a slurry of such concentration, particles of the size required for dielectric fillers can be efficiently obtained.

[0049] In the above method for producing the titanium oxide composition, a granulation step is followed by a calcination step of the granules at a temperature of 1050 to 1300°C. Titanium oxide has a high dielectric loss tangent due to the influence of hydroxyl groups and adsorbed water on its surface, but by calcining at a temperature of 1050°C or higher, a titanium oxide composition with fewer hydroxyl groups and adsorbed water on the surface and a low dielectric loss tangent can be obtained. Furthermore, while higher calcination temperatures increase the particle size of the titanium oxide composition, oxygen vacancies are generated, and the dielectric loss tangent also increases. By calcining at a temperature of 1300°C or lower, the particle size can be increased while suppressing the generation of oxygen vacancies. In addition, during the calcination step, some of the additive elements selected from the group consisting of Si, Al, and W are doped into the titanium oxide, filling in the oxygen vacancies of the titanium oxide. As a result, a titanium oxide composition with a large particle size and a low dielectric loss tangent can be obtained. Of the additive elements selected from the group consisting of Si, Al, and W, those that are not doped into the titanium oxide become oxides. The firing temperature is preferably 1050 to 1300°C. More preferably 1050 to 1200°C, and even more preferably 1050 to 1150°C. The firing time is not particularly limited as long as sufficient firing is achieved, but it is preferably 1 to 50 hours. More preferably 2 to 15 hours, and even more preferably 2 to 8 hours.

[0050] The manufacturing method of the above titanium oxide composition may include other steps as long as it includes a step of manufacturing a granulated product of titanium oxide and a simple substance and / or compound of an element selected from the group consisting of Si, Al, and W, and a step of firing the granulated product at a temperature of 1050 to 1300°C. Other steps include a step of crushing the fired product obtained in the firing step, a step of classifying, and the like.

Example

[0051] Specific examples are given below to explain the present invention in detail, but the present invention is not limited to only these examples. Unless otherwise specified, “%” and “wt%” mean “weight% (mass%)”. The measurement methods for each physical property are as follows.

[0052] <Real part of complex dielectric constant, dielectric loss tangent, relative dielectric constant> The real part of the complex dielectric constant, dielectric loss tangent, and relative dielectric constant of the powder were measured using a dielectric constant measuring device ADMS01Nc1 (manufactured by A&T Co., Ltd.) and an attached 1 GHz resonator. <Evaluation by ultraviolet-visible spectrophotometer> The diffuse reflection spectrum of the sample was measured by measuring the wavelength range of 250 to 800 nm using an ultraviolet-visible near-infrared spectrophotometer (JASCO, V-570). BaSO4 was used as a reference, and the reflectance was converted to absorbance using the Kubelka-Munk function. The values in the wavelength range of 250 to 800 nm were normalized so that the absorbance at 350 nm of the obtained spectrum became 1, and the absorbance at 700 nm was read. <Specific surface area (BET-SSA)> In accordance with the provisions of JIS Z8830 (2013), after heat-treating the sample in a nitrogen atmosphere at 230°C for 60 minutes, the specific surface area (BET-SSA) was measured using a specific surface area measuring device (manufactured by Mountech Co., Ltd., trade name “Macsorb HM-1220”). [[ID=二十二]]

[0053] <TiO2 purity Fluorescent X-ray> The concentrations of additive elements in the titanium dioxide composition were measured using X-ray fluorescence (Rigaku Primus II) in EZ SCan mode and determined as weight percent relative to TiO2. These concentrations are listed in Table 1 as the content of additive elements in the titanium dioxide composition / TiO2. <Median diameter D50 of titanium oxide composition, (D90-D10) / D50> The median diameters D50 and (D90-D10) / D50 were measured using a laser diffraction / scattering particle size distribution analyzer (Horiba, Ltd., model LA-950) as follows: 0.1 g of the sample was added to 60 mL of 0.025 wt% sodium hexametaphosphate aqueous solution, and a suspension was prepared by thoroughly dispersing it using an ultrasonic homogenizer (US-600, manufactured by Nippon Seiki Seisakusho Co., Ltd.). The suspension was then measured under the following conditions: dispersion medium refractive index (1.33: 0.025 wt% sodium hexametaphosphate aqueous solution), sample refractive index 2.75, flow rate 50%, ultrasonic dispersion for 1 minute, and transmittance 80-95%. <Thermogravimetric analysis> Thermogravimetric analysis of the powder was performed using a differential thermal and thermogravimetric simultaneous measurement device STA7300 (Hitachi High-Tech Science Co., Ltd.). The weight was measured when the temperature was raised from room temperature to 200°C at a rate of 10°C / min. From the measurement results, the weight change rate relative to the initial weight (Y value), with respect to the weight at 200°C (X value), was calculated using the following formula. Thermogravimetric analysis (%)=(YX) / Y*100 <Electron Microscope Observation> Powder electron microscope images were observed using a field emission scanning electron microscope JSM-7000F (JEOL Ltd.).

[0054] Example 1 Anatase-type titanium dioxide (manufactured by Sakai Chemical Industry Co., Ltd., product name "SSP-25", specific surface area 270 m²) 2Titanium dioxide ( / g) was repulped in pure water, and then silica (manufactured by Nissan Chemical Corporation, trade name "Snowtex") was added at a ratio of 2.3% by weight relative to titanium dioxide. Subsequently, the granules obtained by spray drying after spray granulation were calcined at 1100°C for 4 hours to obtain a titanium dioxide composition with a median diameter of 16.1 μm. A scanning electron microscope image of the obtained titanium dioxide is shown in Figure 1, and the particle size distribution is shown in Figure 2. The ratio of (D90-D10) / D50 in the particle size distribution was 0.67.

[0055] Example 2 A titanium dioxide composition was obtained in the same manner as in Example 1, except that the amount of silica in Example 1 was 4.2% by weight as silicon relative to titanium dioxide.

[0056] Example 3 A titanium oxide composition was obtained in the same manner as in Example 1, except that the amount of silica in Example 1 was 7.5% by weight as silicon relative to titanium oxide.

[0057] Example 4 Anatase-type titanium dioxide (manufactured by Sakai Chemical Industry Co., Ltd., product name "SSP-25", specific surface area 270 m²) 2 Titanium dioxide granules were obtained by repulping ( / g) in pure water and then spray-drying by spray granulation. 1.74 g of aluminum acetate (Kanto Chemical Co., Ltd.) was suspended in 8 mL of deionized water. 10 g of titanium dioxide granules was placed in a plastic bag, the suspension was sprayed onto it, and the bag was repeatedly shaken after drying until the entire volume was sprayed. The bag was then calcined at 1100 °C for 4 hours to obtain a titanium dioxide composition with a median diameter of 11.6 μm.

[0058] Example 5 A titanium dioxide composition was obtained in the same manner as in Example 4, except that aluminum acetate in Example 4 was replaced with 0.593 g of ammonium tungstate-para-pentahydrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0059] Comparative Example 1 Titanium oxide was obtained in the same manner as in Example 1, except that silica was not added.

[0060] Comparative Example 2 Anatase-type titanium dioxide (manufactured by Sakai Chemical Industry Co., Ltd., product name "SSP-25", specific surface area 270 m²) 2 A titanium oxide composition with a median diameter of 15.3 μm was obtained by calcining ( / g) at 1100°C for 4 hours. The particle size distribution is shown in Figure 2. The ratio of (D90-D10) / D50 in the particle size distribution was 11.25.

[0061] Comparative Example 3 The titanium oxide composition with a median diameter of 40.3 μm was obtained by synthesizing in the same manner as Comparative Example 2, except that the firing temperature was set to 1400°C. The particle size distribution is shown in Figure 2. The ratio of (D90-D10) / D50 in the particle size distribution was 2.26.

[0062] Comparative Example 4 Silica (manufactured by Nissan Chemical Corporation, product name "Snowtex") was dried and calcined at 1100°C for 4 hours. The calcined silica was then placed in a plastic bag and physically mixed with titanium dioxide from Comparative Example 1, with the silica accounting for 4.7% by weight of silicon, to obtain a titanium dioxide composition.

[0063] Comparative Example 5 A titanium oxide composition was obtained in the same manner as in Example 1, except that the firing temperature was set to 1000°C.

[0064] Table 1 shows the types and amounts of additive elements used, whether or not granulation was performed, the calcination temperature, and the various measurement results of the obtained titanium oxide compositions or titanium oxide in Examples 1-5 and Comparative Examples 1-5. Furthermore, in ultraviolet-visible spectroscopy observations, the absorption edge wavelengths around 400 nm for the titanium dioxide compositions of Examples 1 to 3 were 426, 426, and 400 nm, respectively. This indicates a shift of approximately 5 to 35 nm towards shorter wavelengths compared to the absorption edge of 433 nm for the titanium dioxide of Comparative Example 1.

[0065] [Table 1]

[0066] As shown in Table 1, in Examples 1 to 5, where granules containing titanium dioxide and the additive elements Si, Al, or W were produced and then calcined at 1100°C, titanium dioxide compositions were obtained with a tanδ of less than 0.001, a dielectric constant of 10 or more, and an average particle size in the range of 10 to 30 μm. Regarding the production of granules containing titanium dioxide and additives, the results showed that titanium dioxide compositions with large particle size, low dielectric loss tangent, and high dielectric constant were obtained not only when the additive was added to the titanium dioxide before granulation (Examples 1 to 3), but also when the additive was added after granulation (Examples 4 and 5). Furthermore, as shown in Figure 2, the particle size distribution of the titanium dioxide compositions obtained in this way is very sharp, which is advantageous in terms of the moldability of the resin compositions to which the titanium dioxide compositions are added. On the other hand, when fired at around 1100°C without granulation, sintering did not progress well, and the particle size became less than 10 μm (Comparative Example 2). When fired at an even higher temperature of 1400°C to promote sintering, the median diameter became 35 μm or more, and the dielectric loss tangent also became very high (Comparative Example 3). At a firing temperature of 1000°C, the weight loss rate determined by thermogravimetric analysis was large, the dielectric loss tangent was high, and the dielectric constant was low (Comparative Example 5). The titanium oxide compositions of Examples 1-3, which were granulated with added silica, had a low absorbance of 0.1 or less at 700 nm. It is known that the absorption of titanium oxide around 500-700 nm originates from the trivalent state of titanium. When titanium oxide undergoes sintering, oxygen vacancies are formed, generating the trivalent state of titanium, which increases the absorbance around 700 nm (see Comparative Example 1). When the trivalent state of titanium is generated in titanium oxide, conductive carriers are produced, which absorb electromagnetic waves, resulting in a high dielectric loss tangent. The titanium oxide compositions of Examples 1-3, which were calcined with added silica, had low absorbance around 700 nm, and a shift in the absorption edge around 400 nm was also observed compared to the titanium oxide of Comparative Example 1. This indicates that silicon partially doping the titanium oxide suppresses the generation of oxygen vacancies. On the other hand, in Comparative Example 4, where titanium oxide was granulated and calcined, and then silica was added, the dielectric loss tangent was high, confirming that a low dielectric loss tangent cannot be achieved by simply physically mixing titanium oxide and silica. These results confirm that the coexistence of certain components such as silica is extremely important when titanium oxide is sintered, and it was confirmed that by using the titanium oxide composition manufacturing method of the present invention, it is possible to synthesize a titanium oxide composition of 10 to 30 μm with a high dielectric constant and low dielectric loss tangent.

Claims

1. The particulate oxide comprises titanium oxide and an oxide of an element selected from the group consisting of Si, Al, and W. The median diameter is 10 to 30 μm. The dielectric loss tangent (tanδ) at frequencies from 200 MHz to 100 GHz is 1 × 10⁻¹⁶ －３ A titanium oxide composition characterized by the following:

2. The titanium oxide composition according to claim 1, characterized in that the relative permittivity (ε) at frequencies from 200 MHz to 100 GHz is 10 or more.

3. BET specific surface area is 0.5 m² ２ The titanium dioxide composition according to claim 1 or 2, characterized in that it is less than or equal to / g.

4. A titanium oxide composition according to any one of claims 1 to 3, characterized in that it contains 0.05 to 10% by weight of an element selected from the group consisting of Si, Al, and W relative to titanium oxide.

5. A resin composition characterized by comprising the titanium oxide composition and a resin according to any one of claims 1 to 4.

6. A material for electronic components, characterized by comprising the resin composition described in claim 5.

7. An electronic component characterized by being manufactured using the electronic component material described in claim 6.

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