Spherical silica particle powder and method for producing spherical silica particle powder

Abstract

This invention provides an inorganic material with a high dielectric constant and a low dielectric loss tangent. The spherical silica particle powder of this invention comprises a plurality of spherical silica particles loaded with elements. These spherical silica particles are particles on which at least one of a metal element M is loaded. The spherical silica particle powder contains 10-90% by mass of the metal element M. The relative dielectric constant of the spherical silica particle powder at a frequency of 1 GHz is 7.0-300, and the dielectric loss tangent is less than 0.02. The metal element M is selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

Description

Technical Field

[0001] This invention relates to spherical silica particle powder and a method for manufacturing spherical silica particle powder. Background Technology

[0002] In recent years, with the increase in information communication volume in the communications field, the utilization of high-frequency signals in electronic and communication equipment is expanding. However, applying high-frequency signals to these devices also leads to increased transmission losses in the circuit signals. Therefore, materials used in high-frequency devices are required to have a low dielectric loss tangent.

[0003] Furthermore, with the increasing functionality of related electronic materials and components, there is a demand for further miniaturization of devices. If the relative permittivity of the antenna material assembled inside a communication device increases, further miniaturization can be achieved. Therefore, regarding ceramic fillers (inorganic oxide fillers) used in antenna materials, materials with high permittivity and low dielectric loss tangent are sought (for example, see Non-Patent Literature 1).

[0004] As ceramic fillers with relatively high dielectric constant and high versatility, titanium oxide powder and titanates are known. For example, Patent Document 1 proposes an inorganic oxide powder that comprises spherical titanium oxide powder and aluminum oxide powder, wherein the aluminum content in the inorganic oxide powder is 20 to 50,000 ppm by mass.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: International Publication No. 2022 / 249941

[0008] Non-patent literature

[0009] Non-patent literature 1: AKTagantsev et al: J. of Electroceramics, 11(2003)pp.5-66 Summary of the Invention

[0010] The problem the invention aims to solve

[0011] However, although previously known ceramic fillers have high dielectric constants, their dielectric loss tangents also become high.

[0012] Therefore, the object of the present invention is to provide an inorganic material having a high dielectric constant and a low dielectric loss tangent.

[0013] Solution for solving the problem

[0014] The inventors conducted in-depth research and found that the above-mentioned problems could be solved by spherical silica particle powder containing spherical silica particles on which a specific metal element is loaded in a specific amount, thereby completing the present invention.

[0015] One aspect of the present invention relates to spherical silica particle powder, which is a spherical silica particle powder comprising a plurality of spherical element-loaded silica particles, wherein the spherical element-loaded silica particles are particles on which at least one of the following metal elements M is loaded, the spherical silica particle powder contains 10 to 90% by mass of the metal element M, and the spherical silica particle powder has a relative permittivity of 7.0 to 300 and a dielectric loss tangent of 0.02 or less at a frequency of 1 GHz.

[0016] M: Metallic elements selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

[0017] In addition, another aspect of the present invention relates to a method for manufacturing spherical silica particle powder, which is the above-mentioned method for manufacturing spherical silica particle powder, comprising: using a spherical silica precursor obtained by a wet process, loading the silica precursor with at least one of the following metal elements M.

[0018] M: Metallic elements selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

[0019] In addition, another aspect of the present invention relates to a resin composition comprising 5 to 90% by mass of the above-mentioned spherical silica particle powder.

[0020] In addition, another aspect of the present invention relates to a slurry composition comprising 1 to 80% by mass of the above-mentioned spherical silica particles.

[0021] The effects of the invention

[0022] According to the present invention, spherical silica particles with high dielectric constant and small dielectric loss tangent can be provided. Therefore, when used as a filler in resin materials, the resin formation can be made to have a high dielectric constant and a low dielectric loss tangent, thus making it preferably suitable for antennas and the like in radio wave transmitting devices, enabling the miniaturization of radio wave transmitting devices. Detailed Implementation

[0023] The present invention will now be described, but it is not limited to the examples described below. Furthermore, in this specification, the "~" sign indicating a numerical range refers to the inclusion of the values ​​before and after it as a lower limit and an upper limit.

[0024] In addition, in this specification, "spherical silica particle powder" refers to powder that is an aggregate of spherical silica particles.

[0025] In addition, in this instruction manual, "mass" and "weight" have the same meaning.

[0026] The spherical silica particle powder of the present invention (hereinafter referred to as "this embodiment") comprises a plurality of spherical silica particles loaded with elements. The spherical silica particles loaded with elements are particles on which at least one of the following metal elements M is loaded. The spherical silica particle powder contains 10 to 90% by mass of metal element M. The relative permittivity of the spherical silica particle powder at a frequency of 1 GHz is 7.0 to 300 and the dielectric loss tangent is 0.02 or less.

[0027] M: Metallic elements selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

[0028] By including multiple spherical silica particles loaded with at least one of metal elements M, the bulk polarization within the spherical silica particles is increased, thus increasing the dielectric constant. In addition, by including 10 to 80% by mass of metal element M in the spherical silica particle powder, the band gap of the silica bulk itself is large, thus reducing the dielectric loss tangent.

[0029] Metallic element M is selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table. Examples of Group 2 metallic elements include magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba); examples of Group 3 metallic elements include scandium (Sc), yttrium (Y), and the lanthanides (lanthanum (La), cerium (Ce), etc.); examples of Group 4 metallic elements include titanium (Ti) and zirconium (Zr); examples of Group 12 metallic elements include zinc (Zn) and cadmium (Cd); examples of Group 13 metallic elements include aluminum (Al) and gallium (Ga); examples of Group 14 metallic elements include germanium (Ge) and lead (Pb); and examples of Group 15 metallic elements include antimony (Sb) and bismuth (Bi).

[0030] Among these, metallic elements selected from the fourth to sixth periods of the periodic table and from groups 2, 3, 4, 12, 14, and 15 are preferred. Magnesium, calcium, barium, lanthanum, titanium, zirconium, zinc, lead, antimony, and bismuth are readily available and have relatively low toxicity, and are therefore more preferred. From the viewpoint of lower toxicity and the potential to further improve the dielectric constant, magnesium, calcium, barium, lanthanum, titanium, zirconium, and bismuth are even more preferred.

[0031] The spherical silica particles contain 10-90% by mass of a metallic element M. If the content of metallic element M is 10% by mass or more, the dielectric constant of the spherical silica particles can be increased; if it is 90% by mass or less, the high band gap characteristic of the original silica can be maintained, thus reducing the dielectric loss tangent of the spherical silica particles. In the spherical silica particles, the content of metallic element M is preferably greater than 10% by mass, more preferably 18% by mass or more, further preferably 30% by mass or more, even more preferably 40% by mass or more, particularly preferably 50% by mass or more, and most preferably 60% by mass or more. Furthermore, the upper limit is preferably 80% by mass or less, more preferably 78% by mass or less, further preferably 75% by mass or less, particularly preferably 70% by mass or less, and most preferably 63% by mass or less.

[0032] The content of metal element M in spherical silica particles can be determined by inductively coupled plasma (ICP) emission spectroscopy after removing silicon, which is the main component, by adding perchloric acid and hydrofluoric acid to the spherical silica particles and calcining them.

[0033] As described above, the spherical silica particle powder of this embodiment contains metal element M in the powder by comprising a plurality of spherical silica particles on which metal element M is loaded. For the spherical silica particles on which element M is loaded, the content of metal element M in the spherical silica particle powder is not particularly limited as long as it is 10-90% by mass. Preferably, the spherical silica particle powder contains 10% or more of element-loaded silica particles, more preferably 30% or more by mass, and even more preferably 50% or more by mass. The spherical silica particle powder may also be composed of element-loaded silica particles (100% by mass).

[0034] Furthermore, in the spherical silica particle powder of this embodiment, as long as the relative permittivity of the powder at a frequency of 1 GHz is 7.0 to 300 and the dielectric loss tangent is 0.02 or less, it may also contain particles other than silica particles loaded with elements, such as spherical silica particles without metal elements, alumina, titanium oxide, titanate, zirconate, and other inorganic particles other than silica.

[0035] The silica particles contained in the spherical silica powder are spherical, and their sphericity is preferably 0.75 to 1.0. If the sphericity is lower, the specific surface area becomes larger, and therefore the dielectric loss tangent tends to increase. Therefore, the sphericity is preferably 0.75 or higher. More preferably, the sphericity is 0.90 or higher, even more preferably 0.93 or higher, and the closer to 1.0, the more preferred.

[0036] Sphericity can be expressed as follows: For any 100 particles in the photographic projection of spherical silica powder obtained by scanning electron microscopy (SEM), their maximum diameter (DL) and orthogonal minor diameter (DS) are measured, and the average value of the calculated ratio of minimum diameter (DS) to maximum diameter (DL) (DS / DL) is used to represent it.

[0037] The spherical silica particles of this embodiment have a dielectric loss tangent of 0.02 or less at a frequency of 1 GHz. If the dielectric loss tangent of the spherical silica particles at a frequency of 1 GHz is 0.02 or less, a substrate or sheet with improved high-frequency characteristics can be formed. It should be noted that, particularly in the determination of the dielectric loss tangent and dielectric constant of the powder, the sample space becomes smaller and the measurement accuracy deteriorates at frequencies above 10 GHz; therefore, the measurement values ​​at a frequency of 1 GHz are used in this invention.

[0038] The dielectric loss tangent of the spherical silica particles is preferably 0.01 or less, more preferably 0.009 or less, further preferably 0.007 or less, even more preferably 0.005 or less, particularly preferably 0.003 or less, and most preferably 0.001 or less. The smaller the dielectric loss tangent, the better the transmission loss of the circuit can be suppressed; therefore, the lower limit value is not particularly limited.

[0039] Furthermore, the relative permittivity of the spherical silica particles in this embodiment is 7.0 to 300 at a frequency of 1 GHz. If the relative permittivity of the spherical silica particles at a frequency of 1 GHz is 7.0 or higher, the effective wavelength of the electromagnetic waves in the medium can be sufficiently reduced; if it is 300 or lower, a low dielectric loss tangent can be achieved. A relative permittivity of 10 or higher is more preferred, further preferred to be 20 or higher, and particularly preferred to be 50 or higher. Furthermore, a relative permittivity of 150 or lower is more preferred, further preferred to be 130 or lower, particularly preferred to be 120 or lower, and most preferably 100 or lower.

[0040] The dielectric loss tangent and relative permittivity were measured using a dedicated apparatus (e.g., the "Vector Network Analyzer E5063A" manufactured by KEYCOM Co., Ltd.) via a perturbation-mode resonator method on particulate powder that had been dried according to the method described in the examples. Specifically, in a resin tube with a diameter of 15 mm and a length of 40 mm, the bottom surface was sealed with tape, dried powder was filled, and the tube was tapped 5 times before further filling with powder. This operation was repeated 3 times, and the top surface was sealed with tape to obtain a tube uniformly filled with powder. After measuring the blank using an empty resin tube with a diameter of 15 mm and a length of 40 mm sealed with the same mass of tape, the measurement was performed on the tube uniformly filled with powder, thereby obtaining the dielectric loss tangent and relative permittivity.

[0041] The median particle size (d50) of the spherical silica particles in this embodiment is preferably 0.5 to 20 μm. When the median particle size is 0.5 μm or more, the dielectric loss tangent can be significantly reduced. Furthermore, if the median particle size becomes too large, the particle size value increases, and therefore, when the resin composition containing the spherical silica particles is made into, for example, a sheet, the minimum sheet thickness increases. Therefore, the median particle size is preferably 20 μm or less. The median particle size of the spherical silica particles is more preferably 0.5 to 10 μm, further preferably 1 to 10 μm, and particularly preferably 1 to 5 μm.

[0042] From the viewpoint of improving the uniform dispersion of the spherical silica particles in the resin composition and improving the interaction between the spherical silica particles and the resin, the particle size at which the cumulative volume of the particle size distribution curve is 10%, i.e., the 10% particle size (d10), is preferably 0.5 to 5.0 μm, more preferably 1.0 to 5.0 μm, and even more preferably 1.0 to 3.0 μm.

[0043] From the viewpoint of improving the uniform dispersion in the resin composition and enhancing the interaction between the spherical silica particles and the resin, the ratio of the median particle size d50 to the 10% particle size d10 (d50 / d10) is preferably greater than 1.0 and less than 5.0, more preferably 1.3 to 4.0, and even more preferably 1.5 to 3.0.

[0044] The maximum particle size (Dmax) of the spherical silica powder is preferably 150 times or less, more preferably 100 times or less, further preferably 50 times or less, and particularly preferably 10 times or less than the median particle size. If the maximum particle size is 150 times or less than the median particle size, it is less likely to become a defect when processing sheets, for example, using spherical silica powder. Furthermore, the maximum particle size is preferably 1.2 times or more than the median particle size, more preferably 1.5 times or more, and further preferably 2 times or more.

[0045] The median particle size is the cumulative 50% particle size based on a volume reference, determined using a laser diffraction-based particle size distribution measuring device (e.g., MicrotracBEL Co., Ltd.'s "MT3300EXII"). Specifically, by measuring particle size distribution using laser diffraction / scattering, and setting the total volume of spherical silica particles to 100%, a cumulative curve is obtained; the median particle size is the particle size at the point where the cumulative volume reaches 50% on this curve.

[0046] The 10% particle size and the maximum particle size were also obtained by the same determination as the median particle size.

[0047] In this embodiment, the particle size distribution of the spherical silica particles is preferably unimodal. The unimodal particle size distribution of the silica particles can be confirmed by the presence of only one peak in the particle size distribution based on laser diffraction scattering.

[0048] In this embodiment, the specific surface area of ​​the spherical silica particles is preferably 0.1 to 5.0 m². 2 The range is / g. If the specific surface area is 0.1m² 2 When the resin composition contains spherical silica particles of g or higher, the contact points with the resin are sufficient, resulting in better integration with the resin. Additionally, the specific surface area is 5.0 m² / g. 2 When the specific surface area is below 0.1 g, the dielectric loss tangent can be reduced, thus exhibiting excellent low dielectric loss tangent in the resin composition. Furthermore, the small specific surface area improves the flowability and dispersibility in the resin composition. A specific surface area of ​​0.1 m² is preferred. 2 / g or more, preferably 0.2m 2 / g or more, further preferably 0.5m 2 / g or more, and preferably 5.0m 2 / g or less, preferably 4.0m 2 / g or less, more preferably 3.5m 2 / g or less, especially preferably 3.0m 2 Below / g. It should be noted that the specific surface area is less than 0.1m². 2 Powder with a density of / g is practically difficult to obtain.

[0049] Specific surface area is determined using a multi-point BET method based on nitrogen adsorption using a specific surface area / pore distribution measuring device (such as Microtrac BEL's "BELSORP-miniII" or Micromeritics' "TRISTAR II"). Specifically, 0.1 g of sample is filled into a glass cell for measurement, vacuum dried at 230°C for 5 hours, and then measured at 11 points where the relative pressure range of 0.05 to 0.25 is logarithmically divided. The data obtained are analyzed using the multi-point BET method to obtain the specific surface area.

[0050] Furthermore, the specific surface area A(m²) of the spherical silica particles is... 2 The product of the median particle size (g) and the median particle size d50 (μm), A×d50, is preferably 2.7~5.0 μm·m. 2 / g, more preferably 2.7~4.5μm·m 2 / g, further preferably 2.7~4.0μm·m 2 / g. The theoretical value of A×d50 is 2.7 [from specific surface area = 6 / (silicon dioxide true density 2.2 (g / cm³)]. 3 [A×d50 (μm)] is derived from the median particle size d50. Values ​​smaller than this are difficult to achieve in reality. The larger the value of A×d50, the larger the specific surface area per unit particle size and the larger the dielectric loss tangent. Therefore, A×d50 is preferably 5.0 μm·m. 2 / g or less.

[0051] The spherical silica particles in this embodiment can be treated with a silane coupling agent.

[0052] By treating the surface of silica particles with a silane coupling agent, the amount of residual silanol groups on the surface is reduced, the surface is hydrophobic, which can inhibit water adsorption and improve dielectric loss. Furthermore, when the resin composition is made, the affinity with the resin is improved, and the dispersibility and strength of the resin film are enhanced.

[0053] Types of silane coupling agents include aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, and organosilazane compounds. One type of silane coupling agent can be used, or two or more can be used in combination.

[0054] The amount of silane coupling agent attached is preferably 0.01 to 5 parts by weight, more preferably 0.02 to 5 parts by weight, and even more preferably 0.1 to 2 parts by weight, relative to 100 parts by weight of spherical silica powder. Here, the amount of silane coupling agent attached is preferably 0.01 parts by weight or more, more preferably 0.02 parts by weight or more, and even more preferably 0.1 parts by weight or more, and is also preferably 5 parts by weight or less, and more preferably 2 parts by weight or less, relative to 100 parts by weight of spherical silica powder.

[0055] The surface of the silica particles has been treated with a silane coupling agent, which can be confirmed by IR detection of peaks generated by the substituents of the silane coupling agent. Furthermore, the amount of silane coupling agent attached can be determined by the carbon content.

[0056] (Method for manufacturing spherical silica particles)

[0057] The spherical silica particle powder of this embodiment is manufactured by using a spherical silica precursor obtained by a wet process, and loading the silica precursor with at least one of the following metal elements M.

[0058] M: Metallic elements selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

[0059] The wet process refers to a method that includes the following steps: using a liquid as a silica source to gel it, thereby obtaining spherical silica particle powder. By using the wet process, spherical silica particles can be formed, eliminating the need for particle shape adjustments through crushing or other methods, resulting in particles with a small specific surface area. However, the wet process has difficulty producing particles significantly smaller than their average particle size, and there is a tendency for the specific surface area to decrease after calcination. Additionally, the wet process allows for easier control of particle size.

[0060] Examples of wet processes include spraying and emulsion gelation. As an emulsion gelation method, a preferred method is to emulsify a dispersed phase containing a silica precursor and a continuous phase, and then gel the resulting emulsion to obtain spherical silica precursors. As an emulsification method, a preferred method is to supply the dispersed phase containing the silica precursor to the continuous phase via micropores or a porous membrane to produce an emulsion. This produces an emulsion with uniform droplet diameter, resulting in spherical silica particles with uniform particle size. Micromixing and membrane emulsification methods can be used as such emulsification methods. For example, micromixing is disclosed in International Publication No. 2013 / 062105.

[0061] When the obtained silica precursor has a high water content and the weight reduction rate exceeds 10% after drying at 230°C for 12 hours, it is preferable to dry it to less than 10%.

[0062] Examples of drying methods include spray dryers, static drying using dryers, and ventilation treatment of dry air.

[0063] When silica precursors are sintered into large blocks, they can be broken up. However, if the sintering is too strong, even if broken up, they will not become spherical particles, and pulverization will not produce spherical particles.

[0064] Commercially available silica precursors can be used. Examples of spherical silica precursors obtained by wet processing include the Sunsphere (registered trademark) series manufactured by AGC Si-Tech, such as "Sunsphere H-31", "Sunsphere H-33", "Sunsphere H-51", "Sunsphere H-121", "Sunsphere L-51", and "Sunsphere L-52", as well as "HNP-20B" and "SLT-20" manufactured by AGC Si-Tech.

[0065] The average pore size of the silica precursor is preferably 1.0 to 50.0 nm. When the average pore size is 1.0 nm or more, the metal element M can be sufficiently loaded, and the effects of the present invention can be obtained. In addition, if the average pore size of the silica precursor is 50.0 nm or less, the silica particles can be densified (lower specific surface area) by calcination without leaving pores, thus reducing the dielectric loss tangent. The average pore size is more preferably 2.0 nm or more, further preferably 3.0 nm or more, particularly preferably 5.0 nm or more, and even more preferably 30.0 nm or less, further preferably 20.0 nm or less, and particularly preferably 15.0 nm or less.

[0066] The average pore size was determined using the BJH method based on nitrogen adsorption using a specific surface area / pore distribution measuring device (e.g., MicrotracBEL "BELSORP-miniII", Micromeritics "TRISTAR II", etc.). Specifically, 0.1 g of sample was packed into a glass cell for measurement, vacuum dried at 230 °C for 5 hours, and measurements were taken at points where the relative pressure range of 0.05 to 1.0 was logarithmically divided into 49 equal parts. The data obtained were analyzed using the BJH method to obtain the average pore size.

[0067] The specific surface area of ​​the silica precursor is preferably 100~1000 m². 2 / g. The specific surface area of ​​the silica precursor is 100m². 2 When the content is above / g, it can fully load the metal element M, achieving the effect of the present invention, which is 1000m. 2At a concentration of / g or less, the strength of the silica precursor particles is sufficiently high. More preferably, the specific surface area of ​​the silica precursor is 200 m². 2 / g or more, further preferably 400m 2 / g or more, especially preferably 500m 2 / g or more, and more preferably 800m 2 / g or less, more preferably 700m 2 / g or less, especially preferably 650m 2 / g or less.

[0068] The specific surface area is calculated using the method described above.

[0069] The sphericity of the silica precursor is preferably 0.75 or higher. If the sphericity is 0.75 or higher, it is essentially spherical, thus reducing the specific surface area of ​​the particles and preventing protrusion damage due to particle vibration, preventing the active surface from being exposed, thereby enabling low dielectric conversion of the silica particles. A sphericity of 0.90 or higher is more preferred, particularly 0.93 or higher, and since closer to a perfect sphere is preferable, 1.0 is most preferred.

[0070] The sphericity of the silica precursor was determined using the method described above.

[0071] The median particle size (d50) of the silica precursor is preferably 0.5 to 20 μm. If the median particle size is 0.5 μm or more, spherical particles can be formed after calcination to reduce the specific surface area. If it is 20 μm or less, it can be easily used as a filler in easily moldable resins. The median particle size is more preferably 1 μm or more, further preferably 1.5 μm or more, particularly preferably 2 μm or more, and even more preferably 10 μm or less, further preferably 5 μm or less, and particularly preferably 4 μm or less.

[0072] The median particle size of the silica precursor was determined by the method described above.

[0073] The pore volume (PV) of the silica precursor is preferably 0.1 to 2.0 g / cc. When the pore volume of the silica precursor is 0.1 g / cc or more, it can effectively load the metal element M, and when it is 2.0 g / cc or less, it can adequately ensure the amount fed into the container, thus improving productivity. The pore volume of the silica precursor is preferably 0.1 g / cc or more, more preferably 0.2 g / cc or more, even more preferably 0.5 g / cc or more, particularly preferably 0.7 g / cc or more, and preferably 2.0 g / cc or less, more preferably 1.7 g / cc or less, even more preferably 1.5 g / cc or less, and particularly preferably 1.3 g / cc or less.

[0074] The pore volume was determined using the BJH method based on nitrogen adsorption using a specific surface area / pore distribution measuring device (e.g., MicrotracBEL "BELSORP-miniII", Micromeritics "TRISTAR II", etc.). Specifically, 0.1 g of sample was packed into a glass cell for measurement, vacuum dried at 230 °C for 5 hours, and measurements were taken at points where the relative pressure range of 0.05 to 1.0 was logarithmically divided into 49 equal parts. The data obtained were analyzed using the BJH method to obtain the pore volume.

[0075] Furthermore, the weight reduction rate of the silica precursor after drying at 230°C for 12 hours is preferably 10% or less. If the weight reduction rate is 10% or less, when the silica precursor is calcined with its particles in contact with each other, the particles are less likely to sinter together, and spherical silica powder particles are easily obtained.

[0076] The weight reduction rate is more preferably 9% or less, further preferably 8% or less, and particularly preferably 6% or less. In addition, it is desirable that there is no weight change even when drying at 230°C for 12 hours, so the lower limit is not particularly limited.

[0077] Furthermore, the weight loss on ignition of the silica precursor is preferably 5.0 to 15.0% by mass. Weight loss on ignition is the sum of the mass of water adhering to the silica precursor and the mass of water generated by the condensation of silanol groups contained in the silica precursor. Since the silica precursor has a moderate amount of silanol groups, condensation occurs during calcination, and the number of silanol groups is easily reduced. If the weight loss on ignition is too high, the yield during calcination decreases, and productivity deteriorates. Therefore, the weight loss on ignition of the silica precursor is more preferably 13.0% by mass or less, and most preferably 12.0% by mass or less. If the weight loss on ignition is too low, silanol groups are easily retained during calcination. Therefore, the weight loss on ignition of the silica precursor is more preferably 6.0% by mass or more, and most preferably 7.0% by mass or more.

[0078] Here, the loss on ignition is calculated according to JIS K0067:1992 as the mass loss when 1g of silica precursor is heated and dried at 850°C for 0.5 hours.

[0079] In the manufacturing method of this embodiment, a metal element M is loaded onto a silica precursor, but it is preferable to first clean the silica precursor. Cleaning is preferably performed using, for example, hydrochloric acid, sulfuric acid, or nitric acid.

[0080] Specifically, when hydrochloric acid is used for cleaning, the silica precursor is dispersed in an aqueous hydrochloric acid solution, followed by solid-liquid separation. The filter cake is then washed with water and dried. This results in a state where the alkaline components have been removed from the silica precursor.

[0081] Next, a metal element M is added to the silicon dioxide precursor. The metal element M is selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table, with specific and preferred examples as described above. The metal element M exists in the form of oxides, hydrates, chlorides, nitrates, sulfates, etc. For example, if it is bismuth (Bi), bismuth nitrate hydrate can be used; if it is lead (Pb), lead nitrate can be used; if it is zinc (Zn), zinc sulfate hydrate can be used; if it is lanthanum (La), lanthanum nitrate hydrate can be used; if it is titanium (Ti), titanium sulfate can be used; if it is barium (Ba), barium nitrate can be used; and if it is antimony (Sb), antimony chloride can be used.

[0082] To react a compound containing metal element M with a solvent, a washed silica precursor is added. Examples of solvents include water, alcohols, and acetone. It should be noted that the solvent can be used at room temperature or after heating.

[0083] Regarding the mixing ratio of the silica precursor and the compound containing metal element M, it is preferable to mix them such that the final spherical silica powder contains 10-90% by mass of metal element M. The amount of the compound containing metal element M is preferably in the range of 20-700 parts by mass relative to 100 parts by mass of the silica precursor. The content of the compound containing metal element M is more preferably greater than 20 parts by mass relative to 100 parts by mass of the silica precursor, further preferably 50 parts by mass or more, particularly preferably 100 parts by mass or more, and preferably 700 parts by mass or less, more preferably 600 parts by mass or less.

[0084] As a mixing method, mixing devices such as evaporators, Henschel mixers, and Notta mixers can be used.

[0085] After thoroughly mixing a silica precursor with a compound containing a metal element M, the mixture is dried to form a powder, which is then calcined. Through calcination, the metal element M is fixed within the voids of the silica precursor, and the silica precursor is solidified and densified, while the number of silanol groups on the surface is reduced. This reduces the dielectric loss tangent of the silica powder particles.

[0086] The heat treatment temperature during calcination is preferably 700~1600℃. If the treatment temperature is too low, calcination takes longer and productivity decreases. Conversely, if the temperature is too high, particles tend to aggregate, and the particle size in the resin composition tends to increase. The treatment temperature is more preferably 800℃ or higher, more preferably 900℃ or higher, and even more preferably 1500℃ or lower, and even more preferably 1400℃ or lower.

[0087] The heat treatment time can be adjusted appropriately according to the equipment used, the roasting temperature, etc. For example, it is preferred to perform the heat treatment for 0.5 to 50 hours, and more preferably 1 to 10 hours.

[0088] The atmosphere during heat treatment can be either oxygen-containing or oxygen-free. For example, it can be calcined in an atmospheric atmosphere, a hydrogen atmosphere, or a nitrogen atmosphere, depending on the transition metal element being loaded.

[0089] There are no particular limitations on the heat treatment method. Examples include heat treatment based on static placement, heat treatment based on rotary kiln, and heat treatment based on spray combustion.

[0090] Spherical silica particles sometimes exhibit weak sintering after calcination, thus requiring crushing. To avoid compromising the effectiveness of the invention and to maintain sphericity and surface area, crushing is preferably performed with a particle sphericity of not less than 0.75. Furthermore, it is preferable that the surface area does not increase due to the crushing process. A significant increase in surface area during crushing refers to the pulverization of some spherical particles, resulting in fine surface damage and the formation of micropowder. An increase in surface area leads to increased viscosity when dispersed in resin and a deterioration of the dielectric loss tangent, which is therefore undesirable.

[0091] Crushing can be carried out using crushing devices such as cyclone mills, jet mills, impact mills, and Wonder Crusher. In addition, crushing can also be carried out using agate mortars and vibrating screens.

[0092] The calcined spherical silica particles can also be surface-treated with a silane coupling agent. Through this process, the silanol groups on the surface of the spherical silica particles react with the silane coupling agent, reducing the number of silanol groups on the surface and improving the dielectric loss tangent. Furthermore, the surface becomes hydrophobic, improving its affinity for resins and thus enhancing resin dispersibility.

[0093] There are no particular restrictions on the surface treatment conditions; they can be any standard surface treatment conditions, and either wet or dry treatment methods can be used. From the viewpoint of achieving uniform treatment, wet treatment is preferred.

[0094] Examples of silane coupling agents used in surface treatment include aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, and organosilazane compounds. One or more of these can be used in combination.

[0095] Specifically, as surface treatment agents, examples include: aminopropylmethoxysilane, aminopropyltriethoxysilane, ureopropyltriethoxysilane, N-phenylaminopropyltrimethoxysilane, N-2-(aminoethyl)aminopropyltrimethoxysilane, and other aminosilane-based coupling agents; epoxypropoxypropyltrimethoxysilane, epoxypropoxypropyltriethoxysilane, epoxypropoxypropylmethyldiethoxysilane, glycidylbutyltrimethoxysilane, (3,4-epoxycyclohexyl)ethyltrimethoxysilane, and other epoxysilane-based coupling agents; mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, and other mercaptosilane-based coupling agents; methyltrimethoxysilane, vinyltrimethoxysilane, octadecane, etc. Silane coupling agents such as trimethoxysilane, phenyltrimethoxysilane, methacryloxypropyltrimethoxysilane, imidazole silane, and triazine silane; CF3(CF2)7CH2CH2Si(OCH3)3, CF3(CF2)7CH2CH2SiCl3, CF3(CF2)7CH2CH2Si(CH3)(OCH3)2, CF3(CF2)7CH2CH2Si(CH3)Cl2, CF3(CF2)5CH2CH2SiCl3, CF3(CF2)5CH2CH2Si(OCH3)3, CF3CH2CH2SiCl3, CF3CH2CH2Si(OCH3)3, C8F 17 SO2N(C3H7)CH2CH2CH2Si(OCH3)3, C7F 15 CONHCH2CH2CH2Si(OCH3)3、C8F 17 CO2CH2CH2CH2Si(OCH3)3、C8F 17 Fluorosilane coupling agents such as -O-CF(CF3)CF2-O-C3H6SiCl3 and C3F7-O-(CF(CF3)CF2-O)2-CF(CF3)CONH-(CH2)3Si(OCH3)3; organosilane compounds such as hexamethyldisilazane, hexaphenyldisilazane, trisilazane, cyclotrisilazane, and 1,1,3,3,5,5-hexamethylcyclotrisilazane.

[0096] The amount of silane coupling agent used is preferably 0.01 parts by mass or more, more preferably 0.02 parts by mass or more, and even more preferably 0.10 parts by mass or more, relative to 100 parts by mass of spherical silica particles. It is also preferably 5 parts by mass or less, and more preferably 2 parts by mass or less.

[0097] Examples of methods for treating silica particles with silane coupling agents include: a dry method of spraying silane coupling agents into spherical silica particles; and a wet method of dispersing spherical silica particles in a solvent and then adding silane coupling agents to allow them to react.

[0098] (Resin composition and slurry composition)

[0099] The spherical silica particles of this embodiment exhibit good dispersibility in various solvents and excellent mixability in resin compositions.

[0100] The resin composition of this embodiment comprises the spherical silica particle powder of this embodiment and resin. The content of the spherical silica particle powder is preferably 5 to 90% by mass relative to the total resin composition. If the content of the spherical silica particle powder is 5% by mass or more, a sufficient increase in dielectric constant can be obtained; if it is 90% by mass or less, the mechanical strength of the resin composition can be maintained. From the viewpoint of improving the dielectric constant, the content of the spherical silica particle powder in the resin composition is more preferably 10% by mass or more, further preferably 15% by mass or more, and from the viewpoint of improving mechanical strength, more preferably 85% by mass or less, further preferably 80% by mass or less, particularly preferably 75% by mass or less, and most preferably 70% by mass or less.

[0101] As resins, one or more of the following can be used: epoxy resin, silicone resin, phenolic resin, melamine resin, urea-formaldehyde resin, unsaturated polyester resin, fluororesin, polyimide resin, polyamide-imide resin, polyetherimide, etc.; polyester resins such as polybutylene terephthalate and polyethylene terephthalate; polyphenylene ether resin, polyphenylene sulfide resin, phenolic resin, o-divinylbenzene resin, aromatic polyester resin, polysulfone, liquid crystal polymer, polyethersulfone, polycarbonate, maleimide modified resin, ABS (acrylonitrile-butadiene-styrene) resin, AAS (acrylonitrile-acrylic rubber-styrene) resin, AES (acrylonitrile-ethylene-propylene-diene rubber-styrene) resin, polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-ethylene copolymer (ETFE). The dielectric loss tangent in the resin composition also depends on the properties of the resin, so these factors should be taken into account when selecting the resin to use.

[0102] Thermosetting resins are preferred. A single thermosetting resin can be used, or two or more can be used in combination. Examples of thermosetting resins include epoxy resins, polyphenylene ether resins, polyimide resins, phenolic resins, and o-divinylbenzene resins. From the viewpoints of adhesion and heat resistance, epoxy resins, polyphenylene ether resins, or o-divinylbenzene resins are preferred thermosetting resins.

[0103] From the perspective of adhesion and dielectric properties, the weight-average molecular weight of thermosetting resins is preferably 1000-7000, more preferably 1000-5000, and even more preferably 1000-3000. The weight-average molecular weight is determined by gel permeation chromatography (GPC) using polystyrene conversion.

[0104] From the viewpoints of suppressing uneven distribution of silica particles, reducing water absorption, low dielectric loss tangent, and improving adhesion, the content of spherical silica particle powder relative to 100 parts by weight of thermosetting resin is preferably 10 to 400 parts by weight, more preferably 50 to 300 parts by weight, and even more preferably 70 to 250 parts by weight. In particular, when it is desired that the silica particles are highly packed, the content of the silica particle powder is preferably 80 parts by weight or more, more preferably 90 parts by weight or more.

[0105] Through the aforementioned mechanism, the spherical silica particles are in a fully wetted and uniformly dispersed state, and also readily interact with the thermosetting resin. Therefore, in this composition with a content within this range, i.e., in which the spherical silica particles are more abundant than the thermosetting resin, both components are easily stabilized, enabling the formation of a molded product with excellent adhesion to the metal substrate layer.

[0106] Furthermore, the spherical silica particles of this embodiment can be used as a filler material in a slurry composition. A slurry composition refers to a mud-like composition in which the spherical silica particles of this embodiment are dispersed in an aqueous or oil-based medium.

[0107] The content of spherical silica particles relative to the overall slurry composition is preferably 1 to 80% by mass, more preferably 20 to 80% by mass, even more preferably 40 to 80% by mass, and particularly preferably 50 to 80% by mass. By containing spherical silica particles in this proportion, the viscosity of the dispersion can be appropriately maintained.

[0108] Examples of oil-based media include acetone, methanol, ethanol, butanol, 2-propanol, 1-propanol, isobutanol, 1-butanol, 2-butanol, 2-methoxyethanol, 2-ethoxyethanol, 1-methoxy-2-propanol, 2-acetoxy-1-methoxypropane, propyl acetate, isobutyl acetate, butyl acetate, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, N,N-dimethylformamide, methyl isobutyl ketone, N-methylpyrrolidone, n-hexane, n-heptane, cyclohexane, methylcyclohexane, cyclohexanone, and naphtha as a mixture. These can be used individually or in mixtures of two or more.

[0109] In addition to the resin and medium described above, the resin composition and slurry composition may contain any other components. Examples of such components include surfactants and fillers other than silica. Furthermore, dispersing agents may be added to improve dispersibility.

[0110] The dispersion of spherical silica particles in various compositions can be achieved using dispersion devices similar to those used in pigment dispersion. Examples include: dispersers, homogenizers, planetary mixers, homogenizers (e.g., M Technique's "CLEARMIX", PRIMIX's "FILMIX", Silverson's "Abramix"), paint mixers (Red Devil), colloid mills (e.g., PUC's "PUC colloid mill", IKA's "colloid mill MK"), conical mills (e.g., IKA's "cone mill MKO"), ball mills, sand mills (e.g., Shinmaru Enterprises' "Dyno mill"), grinding mills, bead mills (e.g., Eirich's "DCP mill"), media dispersers such as coball mills, wet jet mills (e.g., Genus PY, SuginoMachine's "Star Burst", Nanozer's "Nanomizer"), and M Technique's "CLEAR" mill. Media-free dispersers such as the "SS-5" and "CROS" manufactured by Nara Machinery Co., Ltd., as well as other roller mills and kneaders, are preferred. It is preferable not to use grinding media (balls, beads, etc.). This is because there is a concern about contamination from abrasive media if grinding media are used. Specifically, media-free dispersers such as wet jet mills (Genus PY manufactured by Genus Co., Ltd., Starburst manufactured by Sugino Machine Co., Ltd., and "Nanomizer" manufactured by Nanozer Co., Ltd.), "CLEAR SS-5" manufactured by M-Technique Co., Ltd., and "MICROS" manufactured by Nara Machinery Co., Ltd. are preferred.

[0111] Furthermore, the dispersion process is preferably carried out at a temperature of 0 to 100°C. By performing the dispersion process within this temperature range, the viscosity of the solvent can be appropriately maintained, thus preserving productivity. Additionally, solvent evaporation can be suppressed, making it easier to control the solid content. The processing temperature is preferably 0 to 100°C, more preferably 5 to 90°C, and even more preferably 10 to 80°C. Here, the processing temperature is more preferably 5°C or higher, even more preferably 10°C or higher, and even more preferably 90°C or lower, and even more preferably 80°C or lower.

[0112] The dispersion time should be set appropriately according to the dispersion device used so as not to cause particle damage. It is preferably 0.5 to 60 minutes, more preferably 0.5 to 10 minutes, and even more preferably 0.5 to 5 minutes.

[0113] Then, the aggregates of spherical silica particles that remained even after dispersion treatment are wet-classified. Examples of wet classification include classification using sieves and centrifugal force. When using sieves, it is preferable to use sieves with a mesh size of 100 μm or less. As a sieve, for example, a metal with a dense lattice structure, such as an electroforming sieve, is preferred.

[0114] The mesh size of the sieve is preferably 0.2 to 100 μm, more preferably 0.5 to 75 μm, even more preferably 0.5 to 50 μm, and particularly preferably 1 to 35 μm. Here, the mesh size of the sieve is preferably 100 μm or less, more preferably 75 μm or less, even more preferably 50 μm or less, and particularly preferably 35 μm or less. Furthermore, it is preferably 0.2 μm or more, more preferably 0.5 μm or more, and even more preferably 1 μm or more.

[0115] Then, it can be diluted or concentrated as needed to adjust to an appropriate concentration. Methods of concentration include gasification concentration and solid-liquid separation.

[0116] It should be noted that in the method for manufacturing the slurry composition of this embodiment, a silane coupling agent may be added to the mixture of solvent and spherical silica particle powder. Examples of silane coupling agents include the aforementioned silane coupling agents.

[0117] When a resin film is made using a resin composition containing the spherical silica particle powder of this embodiment, its dielectric loss tangent at a frequency of 10 GHz is preferably 0.005 or less, more preferably 0.004 or less, and even more preferably 0.0035 or less. If the dielectric loss tangent of the resin film at a frequency of 10 GHz is 0.005 or less, its electrical properties are excellent, and therefore it is expected to be used in electronic devices, communication devices, etc. The smaller the dielectric loss tangent, the better the transmission loss of the circuit can be suppressed, so the lower limit value is not particularly limited.

[0118] Furthermore, when a resin film is made using a resin composition containing the spherical silica particle powder of this embodiment, its relative permittivity at a frequency of 10 GHz is preferably 4.0 to 20.0, with a lower limit preferably of 4.0 or more, more preferably 5.0 or more, further preferably 5.5 or more, and an upper limit preferably 15.0 or less, further preferably 12.0 or less, and particularly preferably 8.0 or less. When the relative permittivity of the resin film at a frequency of 10 GHz is within the aforementioned range, its electrical properties are excellent, and therefore it is expected to be used in electronic devices, communication devices, etc.

[0119] The relative permittivity of the resin film can be determined using a dedicated device (such as the "Vector Network Analyzer E5063A" manufactured by KEYCOM Corporation) via the perturbation resonator method.

[0120] The dielectric loss tangent of a resin film can be measured using a split-column dielectric resonator (SPDR) (e.g., manufactured by Agilent Technologies).

[0121] The spherical silica particles of this embodiment can be used as various filler materials, and are particularly suitable as filler materials for resin compositions used in the manufacture of antenna materials for electronic devices such as personal computers, laptops, and digital cameras, as well as communication devices such as smartphones and game consoles. Specifically, in order to reduce dielectric loss tangent, reduce transmission loss, reduce moisture absorption, and improve peel strength, the silica particles of this embodiment are also expected to be used in resin compositions, prepregs, metal-coated laminates, printed circuit boards, resin sheets, adhesive layers, adhesive films, solder resists, bump reflow soldering, redistribution insulation layers, chip bonding materials, sealing materials, underfills, mold underfills, and laminated inductors, etc.

[0122] As described above, the present invention includes the following: <1> ~ <10> The composition of.

[0123] <1> A spherical silica particle powder, comprising multiple spherical silica particles loaded with elements.

[0124] The spherical element-loaded silica particles are particles in which at least one of the following metal elements M is loaded onto spherical silica particles.

[0125] The spherical silica particles contain 10-90% by mass of the metal element M.

[0126] The spherical silica particles have a relative permittivity of 7.0~300 and a dielectric loss tangent of less than 0.02 at a frequency of 1 GHz.

[0127] M: Metallic elements selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

[0128] <2> According to the above <1> The spherical silica particles powder has a median particle size of 0.5~20μm.

[0129] <3> According to the above <1> or <2> The spherical silica particle powder has a specific surface area of ​​0.1~5.0 m². 2 / g.

[0130] <4> According to the above <1> ~ <3> The spherical silica particle powder described in any one of the above statements, wherein the specific surface area A (m²) of the spherical silica particle powder is... 2 The product of the median particle size (g) and the median particle size d50 (μm), A×d50, is 2.7~5.0 μm·m. 2 / g.

[0131] <5> According to the above <1> ~ <4> The spherical silica particle powder as described in any one of the following, wherein the metal element M is a metal element belonging to the fourth to sixth period of the periodic table and belonging to the second, third, fourth, twelfth, fourteenth, and fifteenth groups.

[0132] <6> A method for manufacturing spherical silica particle powder, wherein the method comprises the following: <1> ~ <5> The method for manufacturing spherical silica particles according to any one of the following methods comprises: using a spherical silica precursor obtained by a wet process, loading the silica precursor with at least one of the following metal elements M.

[0133] M: Metallic elements selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

[0134] <7> According to the above <6> The method for manufacturing spherical silica particles, wherein the pore volume of the silica precursor is 0.1~2.0 g / cc.

[0135] <8> According to the above <6> or <7> The method for manufacturing spherical silica particles, wherein the specific surface area of ​​the silica precursor is 100~1000 m². 2 / g.

[0136] <9> A resin composition comprising 5 to 90% by mass of the above-mentioned <1> ~ <5> The spherical silica particle powder described in any one of the following statements.

[0137] <10> A slurry composition comprising 1 to 80% by mass of the above-mentioned... <1> ~ <5> The spherical silica particle powder described in any one of the following statements.

[0138] Example

[0139] The present invention will now be described in detail with reference to the embodiments, but the present invention is not limited to these embodiments. In the following description, common ingredients are the same as those used in the present invention. In addition, unless otherwise specified, "parts" and "%" mean "parts by mass" and "% by mass". Examples 1-27 and 29-31 are examples, and Examples 28 and 32 are comparative examples.

[0140] The added compounds used in the following examples are described below.

[0141] Bismuth nitrate pentahydrate, lead nitrate (II), zinc sulfate heptahydrate, lanthanum nitrate hexahydrate, barium nitrate, antimony trichloride, 30% titanium sulfate (IV) solution, tin chloride (II), zinc chloride, tungsten chloride (VI): Manufactured by Fujifilm and Koko Pure Chemical Industries Co., Ltd.

[0142] Calcium nitrate tetrahydrate, strontium nitrate: manufactured by Aldrich

[0143] <Experimental Example 1>

[0144] (Example 1)

[0145] As a spherical silica precursor, silica particles (Sunsphere H-31, manufactured by AGC Si-Tech, with a median particle size (d50) of 3 μm, a pore volume (PV) of 1.00 g / cc, and a BET specific surface area of ​​650 m²) manufactured by wet process were used. 2 / g, oil absorption 150mL / 100g).

[0146] 100g of spherical silica precursor was dispersed in 1L of 1M hydrochloric acid, and then solid-liquid separation was performed. The resulting filter cake was washed with 10L of distilled water and dried under vacuum at 200℃ to obtain cleaned silica granular powder.

[0147] 100g of cleaned silica granules were placed in a container, and a solution obtained by dissolving 400g of bismuth nitrate pentahydrate (manufactured by Fujifilm and Kojun Chemical Co., Ltd.) in 1L of acetone was added. The solvent was removed by distillation while the container was rotating in an evaporator, followed by atmospheric calcination at 800°C. The resulting granules were then pulverized using a Wand crusher to obtain 400g of element-loaded silica granules 1.

[0148] (Example 2~Example 12)

[0149] As shown in Table 1, the added compounds and their amounts, as well as the loading conditions, were changed, and otherwise, silica particles 2-12 loaded with elements were obtained in the same manner as in Example 1.

[0150] (Example 13)

[0151] As a spherical silica precursor, silica particle powder (Sunsphere H-51, manufactured by AGC Si-Tech, with a median particle size (d50) of 5 μm, a pore solution (PV) of 0.8 g / cc, and a BET specific surface area of ​​700 m²) manufactured by wet process was used. 2 / g, oil absorption 150mL / 100g), otherwise, similar to Example 1, silica particle powder 13 loaded with elements was obtained.

[0152] (Example 14)

[0153] As a spherical silica precursor, silica particles (Sunsphere H-121, manufactured by AGC Si-Tech, with a median particle size (d50) of 12 μm, a pore volume (PV) of 0.8 g / cc, and a BET specific surface area of ​​680 m²) manufactured by a wet process were used. 2 / g, oil absorption 150mL / 100g), otherwise, similar to Example 1, silica particle powder 14 loaded with elements was obtained.

[0154] (Example 15)

[0155] As a spherical silica precursor, silica particles (Sunsphere H-33, manufactured by AGC Si-Tech, with a median particle size (d50) of 4 μm, a pore volume (PV) of 1.7 g / cc, and a BET specific surface area of ​​700 m²) manufactured by wet process were used. 2 / g, oil absorption 400mL / 100g), otherwise, similar to Example 1, silica particle powder 15 loaded with elements was obtained.

[0156] (Example 16)

[0157] As a spherical silica precursor, silica particles (Sunsphere L-51, manufactured by AGC Si-Tech, with a median particle size (d50) of 5 μm, a pore volume (PV) of 0.7 g / cc, and a BET specific surface area of ​​420 m²) manufactured by wet process were used. 2 / g, oil absorption 150mL / 100g), otherwise, similar to Example 1, silica particle powder 16 loaded with elements was obtained.

[0158] (Example 17)

[0159] As a spherical silica precursor, silica particles (Sunsphere L-52, manufactured by AGC Si-Tech, with a median particle size (d50) of 5 μm, a pore volume (PV) of 1.3 g / cc, and a BET specific surface area of ​​400 m²) manufactured by wet process were used. 2 / g, oil absorption 300mL / 100g), otherwise, similar to Example 1, silica particle powder 17 loaded with elements was obtained.

[0160] (Example 18)

[0161] As a spherical silica precursor, silica particles (Sunsphere H-31, manufactured by AGC Si-Tech, with a median particle size (d50) of 4 μm, a pore volume (PV) of 0.1 g / cc, and a BET specific surface area of ​​200 m²) manufactured by wet process were used. 2 The same method as in Example 1 was used to obtain cleaned silica particle powder (with an oil absorption of 150 mL / 100 g). Next, the cleaned silica particle powder was calcined at 800°C for 1 hour to obtain calcined silica particle powder.

[0162] 100g of calcined silica granules were placed in a container, and a solution obtained by dissolving 400g of bismuth nitrate pentahydrate (manufactured by FUJIFILM Wako Pure Chemical Corporation) in 1L of acetone was added. The solvent was removed by distillation while the container was rotated using an evaporator, and then the mixture was calcined at 1240°C under atmospheric conditions. The resulting powder was then pulverized using a Wand crusher to obtain 400g of element-loaded silica granules 18.

[0163] (Example 19~Example 23)

[0164] As shown in Table 2, the added compounds and their amounts were changed, and otherwise, silica particles 19-23 loaded with elements were obtained in the same manner as in Example 1.

[0165] (Example 24~Example 27)

[0166] As a spherical silica precursor, silica particles (Sunsphere L-52, manufactured by AGC Si-Tech, with a median particle size (d50) of 5 μm, a pore volume (PV) of 1.3 g / cc, and a BET specific surface area of ​​400 m²) manufactured by wet process were used. 2 / g, oil absorption 300mL / 100g), as shown in Table 2, the added compounds and their amounts, and the loading conditions were changed, otherwise, the silica particles loaded with elements 24~27 were obtained in the same manner as in Example 1.

[0167] (Example 28)

[0168] The silica particles before loading with metal elements were used as the comparison objects in Examples 1 to 27.

[0169] As a spherical silica precursor, silica particles (Sunsphere H-31, manufactured by AGC Si-Tech, with a median particle size (d50) of 3 μm, a pore volume (PV) of 1.00 g / cc, and a BET specific surface area of ​​650 m²) manufactured by wet process were used. 2 / g, oil absorption 150mL / 100g).

[0170] 100g of spherical silica precursor was dispersed in 1L of 1M hydrochloric acid, and then solid-liquid separation was performed. The resulting filter cake was washed with 10L of distilled water and dried under vacuum at 200℃ to obtain cleaned silica granular powder.

[0171] The cleaned silica granules were calcined at 1200°C for 1 hour, and the resulting granules were crushed using a Wande crusher to obtain 100g of silica granules 28.

[0172] The spherical silica particles from Examples 1 to 28 were evaluated as follows. The results are shown in Tables 1 and 2.

[0173] "evaluate"

[0174] <Relative permittivity, dielectric loss tangent>

[0175] Using a dedicated apparatus (Vector Network Analyzer E5063A, manufactured by KEYCOM), the perturbation resonator method was employed to measure silica particles at a test frequency of 1 GHz, a test temperature of approximately 24 °C, a humidity of approximately 45%, and three measurements.

[0176] First, the powder was vacuum dried at 150°C. One end of a 15mm diameter × 40mm length polytetrafluoroethylene (PTFE) tube was sealed with Teflon (registered trademark) tape. The dried powder was then filled into the tube, and after tapping it 5 times, more powder was added. This process was repeated 3 times. The open end of the tube was then sealed with Teflon tape to obtain a PTFE tube uniformly filled with powder. After measuring the blank using an empty PTFE tube (15mm diameter × 40mm length) sealed with the same mass of Teflon tape, measurements were performed on the PTFE tube uniformly filled with powder. The relative permittivity and dielectric loss tangent were calculated using the powder filling rate in the container.

[0177] <Determination of the content of metallic elements>

[0178] Perchloric acid and hydrofluoric acid were added to silica granules and calcined to remove silicon, which is the main component. The content of metal elements was then determined by inductively coupled plasma (ICP) emission spectroscopy.

[0179] <Particle size (median particle size)>

[0180] The median particle size was determined using a particle size distribution measuring device (MicrotracBEL MT3300EXII) employing laser diffraction. The spherical silica particles were dispersed by ultrasonic waves irradiating the device three times for 60 seconds before measurement. Each measurement was performed twice for 60 seconds, and the average value was calculated.

[0181] Specific surface area

[0182] Spherical silica particles were dried under reduced pressure at 230°C to completely remove moisture, thus preparing a sample. The specific surface area of ​​this sample was determined using a Micromeritics Tristar II automated surface area / pore distribution measuring device via the multi-point BET method under nitrogen atmosphere.

[0183] [Table 1]

[0184]

[0185] [Table 2]

[0186]

[0187] As shown in Tables 1 and 2, compared with Example 28, the silica particles loaded with metal elements in Examples 1 to 27 have a higher relative permittivity and are particulate powders with high permittivity and low dielectric loss tangent.

[0188] <Experimental Example 2>

[0189] (Example 29)

[0190] The following components were weighed: 39 parts by weight of polyphenylene ether (OPE-2st 2200, a toluene solution with 65% solids content, manufactured by Mitsubishi Gas Chemical Co., Ltd.), 21 parts by weight of hydrogenated styrene-based thermoplastic elastomer (Tuftec (registered trademark (M1913))), 10 parts by weight of triallyl isocyanurate, 1 part by weight of α,α'-di(tert-butylperoxy)diisopropylbenzene, 5 parts by weight of toluene, and 140 parts by volume of silica particles loaded with elements prepared in Example 1. The mixture was placed in a polyethylene bottle and kneaded using a planetary disperser to obtain a resin composition.

[0191] (Example 30)

[0192] The element-loaded silica particle powder 4 prepared in Example 4 was used instead of the element-loaded silica particle powder 1, and the resin composition was otherwise obtained in the same manner as in Example 29.

[0193] (Example 31)

[0194] The element-loaded silica particle powder 5 prepared in Example 5 was used instead of the element-loaded silica particle powder 1, and the resin composition was otherwise obtained in the same manner as in Example 29.

[0195] (Example 32)

[0196] The resin composition was obtained in the same manner as in Example 29 except that the silica particle powder 28 prepared in Example 28 was used instead of the element-loaded silica particle powder 1.

[0197] The resin compositions of Examples 29 to 32 were evaluated as follows. The results are shown in Table 3.

[0198] "evaluate"

[0199] <Relative permittivity, dielectric loss tangent>

[0200] The resin composition was vacuum dried at 120°C to remove the solvent, and then pulverized using a shredder. 5g of the pulverized material was measured into a 10cm × 10cm × 0.2mm mold, and low-profile copper foil (thickness: 18μm, Rz: 3.5μm, manufactured by Mitsui Metals Corporation, 3EC-M3-V-18) was stacked on top and bottom, and placed in a vacuum press. Under vacuum and at 1MPa, the temperature was increased to 200°C at a rate of 2.5°C / min, and held at 200°C for 3 hours to obtain a resin-coated metal substrate.

[0201] The obtained resin-coated metal substrate was immersed in an etching solution (Sunhayato, H-1000A, ferric chloride aqueous solution) to completely remove the copper foil on one side, and then dried in an oven at 100°C for 10 minutes.

[0202] The relative permittivity and dielectric loss tangent of the pressed prepreg were measured using a longitudinally separated column dielectric resonator (manufactured by Agilent Technologies) (measurement frequency: 10 GHz).

[0203] [Table 3]

[0204]

[0205] As shown in Table 3, the resin compositions of Examples 29 to 31 have a relative permittivity that is more than twice that of Example 32, and a smaller dielectric loss tangent. The spherical silica particles of the present invention can also exhibit a high relative permittivity and a low dielectric loss tangent in the resin composition.

[0206] The present invention has been described in detail with reference to specific embodiments, but it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on Japanese Patent Application No. 2024-028874, filed on February 28, 2024, the contents of which are incorporated herein by reference.

Claims

1. A spherical silica particle powder, comprising multiple spherical silica particles loaded with elements. The spherical element-loaded silica particles are particles in which at least one of the following metal elements M is loaded onto spherical silica particles. The spherical silica particles contain 10-90% by mass of the metal element M. The spherical silica particles have a relative permittivity of 7.0~300 and a dielectric loss tangent of less than 0.02 at a frequency of 1 GHz. M: Metallic elements selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

2. The spherical silica particle powder according to claim 1, wherein, The median particle size of the spherical silica particles is 0.5~20μm.

3. The spherical silica particle powder according to claim 1, wherein, The specific surface area of ​​the spherical silica particles is 0.1~5.0 m². 2 / g.

4. The spherical silica particle powder according to claim 1, wherein, The specific surface area A(m²) of the spherical silica particles is... 2 The product of the median particle size (g) and the median particle size d50 (μm), A×d50, is 2.7~5.0 μm·m. 2 / g.

5. The spherical silica particle powder according to claim 1, wherein, The metallic element M is a metallic element belonging to the fourth to sixth periods of the periodic table and to groups 2, 3, 4, 12, 14, and 15.

6. A method for manufacturing spherical silica particle powder, as described in any one of claims 1 to 5, comprising: Using a spherical silica precursor obtained by a wet process, the silica precursor is loaded with at least one of the following metal elements M. M: Metallic elements selected from Groups 2, 3, 4, 12, 13, 14, and 15 of the periodic table.

7. The method for manufacturing spherical silica particle powder according to claim 6, wherein, The pore volume of the silica precursor is 0.1~2.0 g / cc.

8. The method for manufacturing spherical silica particle powder according to claim 6, wherein, The specific surface area of ​​the silica precursor is 100~1000 m². 2 / g.

9. A resin composition comprising 5 to 90% by mass of spherical silica particles according to any one of claims 1 to 5.

10. A slurry composition comprising 1 to 80% by mass of spherical silica particles according to any one of claims 1 to 5.

Images