JP2019112270A - Functional filler, granulation filler, carbonization filler, resin composition, molded product, and method for producing the functional filler - Google Patents

Abstract

To provide a functional filler that does not deteriorate absorptivity when a resin composition is made into a molded product, and that can improve antistatic properties of the molded product.SOLUTION: A functional filler of this invention contains a plurality of composite particles, wherein: the composite particles contain a carbon material and a core particle; and the surface of the core particle is provided with a coating section which consists of the carbon material.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a functional filler, a granulated filler, a carbonized filler, a resin composition, a molded product, and a method of producing a functional filler.

  Various techniques have been developed as fillers for dispersion in polymer matrices. For example, Patent Document 1 describes a filler for providing a semiconductive resin composite material which can achieve semiconductivity with a small amount of filling and less variation in volume resistivity. According to Patent Document 1, flat graphite of a specific shape and conductive filler of a specific shape are dispersed in a polymer matrix at a predetermined content ratio and volume ratio, and the volume of the semiconductive resin composite material It is described that when the resistivity is within a predetermined numerical range, a semiconductive property can be achieved with a small filling amount, and a semiconductive resin composite material with less variation in volume resistivity.

Unexamined-Japanese-Patent No. 08-333474

BACKGROUND ART In recent years, in the production process of a molded product formed by molding a resin composition, automation by machine has been advanced for the purpose of improving production efficiency. Accordingly, in the process of producing a molded product, for example, it is required to automatically pick up the molded product and perform operations such as movement, alignment, assembly, and packing. However, when the molded product is charged, the machine to pick up and the molded product adhere electrostatically, which is disadvantageous in that the production efficiency is lowered. Therefore, the molded product is required to improve the antistatic property.
Moreover, in recent years, electronic devices such as for smartphones and vehicles are required to be more and more miniaturized. However, the miniaturization of electronic devices makes them sensitive to electrostatic discharge (ESD). Thus, molded articles for use in electronic devices are required to prevent electrostatic breakdown, that is, to prevent electrostatic discharge.
From the above, in the field of moldings, it is required to improve antistatic properties and antistatic properties.

For example, a method of containing a conductive filler in a resin composition is known as a method of antistatically preventing the molded product formed by molding the above-described resin composition. The inventors of the present invention made a molded product using the filler described in Patent Document 1 and studied to improve the antistatic property and the antistatic property. However, in order to improve the antistatic property and the antistatic property using the filler described in Patent Document 1, a large amount of filler is required. When a large amount of filler is used, the conductive filler is coagulated to form a conductive portion. For example, in the case of using a molded product as an electronic device, there is a disadvantage that the electrical reliability of the electronic device is lowered if there is a conducting portion.
Further, a carbon material such as graphite contained in the filler described in Patent Document 1 has water absorbency. When the molded product contains a large amount of a water-absorbing filler, there is a disadvantage such as reduction in dimensional stability and strength due to water absorption.
Then, this invention makes it a subject to provide the functional filler which can improve the antistatic property of a molding, and antistatic property further, without worsening water absorption when a resin composition is made into a molding. .

The present inventors examined particles which a functional filler contains, in order to improve antistatic property and antistatic property, without deteriorating water absorbency. As a result, by using a functional filler containing a plurality of composite particles in which the covering portion made of a carbon material covers the surface of the core particle, the antistatic property and the antistatic property can be improved without deteriorating the water absorbency of the molded product. Found out.
As described above, the present inventors have found that, by using a functional filler containing a specific composite particle, the antistatic property and the antistatic property can be improved without deteriorating the water absorption of the molded product, and the present invention Is completed.

According to the invention
A functional filler that contains multiple composite particles,
The composite particles include a carbon material and core particles,
A functional filler is provided, wherein the surface of the core particle is provided with a coating made of the carbon material.

Moreover, according to the present invention,
A granulated filler obtained by granulating the functional filler is provided.

Moreover, according to the present invention,
There is provided a carbonized filler obtained by carbonizing the above-mentioned granulated filler.

Moreover, according to the present invention,
There is provided a resin composition comprising the functional filler, the granulated filler, or the carbonized filler, and a resin.

Moreover, according to the present invention,
It is a manufacturing method of the above-mentioned functional filler, and
Mixing the organic resin and the core particles to form a mixture;
A carbonizing step of carbonizing the organic resin to obtain carbides by heat treatment;
A crushing step of crushing the carbide into composite particles;
A method of producing a functional filler is provided.

  According to the present invention, there is provided a functional filler which can improve the antistatic property and the antistatic property of a molded product without deteriorating the water absorption when the resin composition is formed into a molded product.

7 is a TEM photograph of the functional filler of Example 2. 7 is a TEM photograph of the functional filler of Example 2. 7 is a SEM photograph of the carbonized filler according to Example 2. 7 is a SEM photograph of the carbonized filler according to Example 2. 7 is a SEM photograph of the carbonized filler according to Example 2.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description thereof will be appropriately omitted.

  According to the present embodiment, it is a functional filler containing a plurality of composite particles, the composite particles including a carbon material and a core particle, and the surface of the core particle is provided with a covering portion made of the carbon material. , Functional fillers are provided.

The present inventors examined particles which a functional filler contains in order to improve antistatic property and antistatic property. As a result, by using a functional filler containing a plurality of composite particles in which the covering portion made of a carbon material covers the surface of the core particle, a good effect can be obtained from the viewpoint of water absorbency, antistaticity and antistaticity of the molded product. There was found. The reason is presumed as follows.
In the functional filler according to the present embodiment, the composite particles are dispersed in the resin composition to form a conductive path made of a carbon material. In the composite particle, a coated portion made of a carbon material is present on the surface of the core particle. It is inferred that a conductive path can be formed when the composite particles are close to each other. By this conductive path, static electricity is diffused in the molded product, and the antistatic property can be improved. Furthermore, the conductive path can reduce the potential difference due to static electricity between the molded product and the machine to be picked up, and can improve the antistatic property.
Moreover, the specific surface area of a carbon material can be enlarged compared with the conventional functional filler because a coating | coated part exists on the surface of core particle. Thereby, the functional filler according to the present embodiment can reduce the amount of carbon material while forming a suitable conductive path. Therefore, water absorption by the carbon material can be reduced for the molded product.
From the above, it is presumed that the functional filler according to the present embodiment can improve the antistatic property and the antistatic property without deteriorating the water absorption of the molded product.

(Method of producing functional filler)
First, the method for producing a functional filler according to the present embodiment will be described.
The method for producing a functional filler according to the present embodiment includes, for example, a mixing step of mixing an organic resin and core particles to form a mixture, a carbonization step of carbonizing the organic resin by heat treatment to obtain carbides, And c. Crushing the carbide into composite particles.
The details of each step will be described below.

(Mixing process)
In the mixing step, the organic resin and the core particles are mixed to form a mixture.
It does not limit as a method to mix, For example, a 3-roll, a mixer, a ball mill, a vibration ball mill, a bead mill etc. can be used.
Below, the organic resin which is a raw material component of a functional filler, and core particle are demonstrated.

(Organic resin)
The organic resin is not limited, and for example, a thermosetting resin or a thermoplastic resin can be used.
As the thermosetting resin, specifically, aniline resin; phenol resin such as novolak type phenol resin, resol type phenol resin; epoxy resin such as bisphenol type epoxy resin, novolac type epoxy resin; melamine resin; urea resin; cyanate Resin; furan resin; ketone resin; unsaturated polyester resin; urethane resin and the like.
Further, as the thermoplastic resin, specifically, polyethylene, polystyrene, polyacrylonitrile, acrylonitrile-styrene (AS) resin, acrylonitrile-butadiene-styrene (ABS) resin, polypropylene, vinyl chloride, methacrylic resin, polyethylene terephthalate, polyamide And polycarbonate, polyacetal, polyphenylene ether, polybutylene terephthalate, polyphenylene sulfide, polysulfone, polyether sulfone, polyether ether ketone, polyether imide, polyamide imide, polyimide, poly phthalamide and the like.
As the organic resin, one or more of the above specific examples can be used in combination. As the organic resin, it is preferable to use, for example, a thermosetting resin among the above specific examples. Moreover, as a thermosetting resin, it is more preferable to use an aniline resin among the said specific examples, for example. As a result, the organic resin can easily penetrate the surface of the core particle, and the coating can be uniformly deposited on the surface of the core particle. Furthermore, when the amino group of the aniline resin interacts with the functional group present on the surface of the core particle, the coating can be uniformly deposited on the surface of the core particle. Therefore, a suitable conductive path can be formed.

  As an organic resin, what is liquid at temperature 300 degreeC is preferable, for example. As a result, in the carbonization step, the organic resin can be kept liquid even at a high temperature of 300 ° C. when the temperature is raised to the carbonization temperature. As a result, the liquid organic resin intrudes between the core particles by capillary action. A uniform coating layer can be formed on the surface of the core particle by carbonizing the organic resin invading between the core particles and forming a carbon material. Thereby, a suitable conductive path can be formed.

The lower limit of the yield of the organic resin according to the present embodiment is, for example, preferably 10% or more, and more preferably 20% or more, when heat-treated at a temperature of 580 ° C. in the carbonization step, for example. Preferably, it is 30% or more, more preferably 40% or more. This is preferable in that it exhibits excellent performance in terms of antistatic properties and antistatic properties while being excellent in terms of cost, and does not deteriorate the water absorption. Furthermore, when a yield is more than the said lower limit, it is preferable at the point which can suppress that a defect is formed in a shell layer and can form a more uniform conductive path | pass.
The larger the yield, the better, and the upper limit of the yield may be, for example, 100% or less, or 99% or less.

In the method for producing a functional filler according to the present embodiment, the lower limit value of the addition amount of the organic resin is, for example, preferably 1 part by mass or more, and 3 parts by mass or more with respect to 100 parts by mass of core particles. The content is more preferably 5 parts by mass or more, and still more preferably 7 parts by mass or more. Thereby, a coating | coated part can be formed without a defect and a suitable electrically conductive path can be formed.
Moreover, as an upper limit of the addition amount of organic resin, it is preferable that it is 200 mass parts or less, for example, and it is more preferable that it is 100 mass parts or less. Thereby, it can suppress that the conduction | electrical_connection part which the peeling carbon material aggregated is formed by forming a carbon material excessively.

(Core particle)
The core particles are not limited, and those used as fillers for moldings can be selected.
Specific examples of the core particles include inorganic oxides, inorganic nitrides, inorganic carbides, inorganic hydroxides, metals and the like.
Specific examples of the inorganic oxide include silica, alumina, titanium oxide, talc, clay, mica, glass fiber (quartz glass) and the like.
Specific examples of the inorganic nitride include silicon nitride, aluminum nitride and boron nitride.
Specific examples of inorganic carbides include silicon carbide, zirconium carbide, titanium carbide, boron carbide and tantalum carbide.
Moreover, as an inorganic hydroxide, aluminum hydroxide, magnesium hydroxide, etc. are specifically mentioned.
Further, as the metal, specifically, a single metal or an alloy can be used. Specifically, Fe, Cu, Ag, Au or the like can be used as the metal simple substance.
Further, as the alloy, specifically, Fe-36 Ni alloy (: Invar), Fe-42 Ni alloy (: 42 alloy), Fe-32 Ni-5 Co alloy (: Super Invar), Fe-29 Ni-17 Co alloy (: Kovar), Fe-36Ni-12Co alloy (: Elinvar), Ni-28Mo-2Fe alloy, Fe-54Co-9.5Cr (: Stainless Invar), Fe-Si-Al alloy (: Sendust), Fe-Ni alloy ( Fe alloy such as permalloy), AFe ₂ O ₄ (ferrite, where A represents Mn, Co, Ni, Cu or Zn); Cu alloy such as Cu-Al alloy, Cu-Ga alloy; Ag-Pd Alloys, Ag alloys such as Ag-Pd-Cu alloys; Au alloys such as Au-Ag alloys.
As the core particle, it is preferable to use, for example, one or more selected from the group consisting of inorganic oxide, inorganic nitride, inorganic carbide, inorganic hydroxide and metal among the above specific examples, and inorganic oxide, inorganic It is more preferable to use one or more selected from the group consisting of nitrides, inorganic carbides and inorganic hydroxides, and it is further preferable to use an inorganic oxide. Thereby, in the composite particle, the carbon material functions as a conductive component and the core particle functions as an insulating component. Therefore, the molding can form a suitable conductive path. This is convenient from the viewpoint of discharging rapidly from the highly conductive portion and causing no electromagnetic interference.
In addition, for example, when a core particle having higher conductivity than a carbon material such as metal is selected as the core particle, the covering portion can realize a functional filler of a design concept that suppresses excessive conductive performance of the core particle. Thereby, it is also possible to form a suitable conductive path by giving insulation performance to the conventional metal particles.

The lower limit value of the volume resistivity of the core particle is, for example, preferably 1 × 10 ⁸ Ω · cm or more, more preferably 1 × 10 ¹⁰ Ω · cm or more, and 1 × 10 ¹² Ω · cm. It is more preferable that it is more than. Thereby, when a molded article expresses antistatic property and antistatic property, it is convenient at a viewpoint which can control that electric discharges from a conductive part with high conductivity at once. For example, in the case of discharging at one time, when the molded product is used for the application of the electronic device, electromagnetic interference occurs in the electronic device.
The upper limit of the volume resistivity of the core particles may be, for example, less than 1 × 10 ¹⁵ Ω · cm, or 1 × 10 ¹⁴ or less. In the functional filler according to the present embodiment, the core particle has a high insulation performance, since the coating plays a role of forming a suitable conductive path.
In the present embodiment, the volume resistivity of the core particles can be measured, for example, by powder resistance measurement using a resistivity meter. As a commercial item of an apparatus which performs such measurement, for example, powder resistance measurement system (MCP-PD51 type, counter electrode probe of radius 10.0 mm), resistivity meter (Mitsubishi Chemical Analytech Co., Ltd., Hiresta-UX) And the like. Here, the upper limit lower limit value of the volume resistivity of the core particle described above indicates the volume resistivity when a stress of 25.46 MPa is applied to the core particle and measurement is performed.
In the present embodiment, the conditions for measuring the volume resistivity of the core particles are, for example, a temperature of 20 ° C. and a humidity of 40% RH.

The shape of the core particle is not limited, and specifically, a spherical shape, a scaly shape, a needle shape, an irregular shape, and the like can be selected. Among these, as a shape of core particles, for example, a spherical shape is preferable. The conventional filler used for antistatic and antistatic purposes was, for example, based on the concept of forming a conductive path while reducing the amount of filler added by selecting a non-spherical conductive filler. . However, when a filler having a non-spherical shape is used, for example, there is a disadvantage in that the flowability of the resin composition is reduced when molding. On the other hand, the core particle according to the present embodiment has a spherical shape, so that the composite particle can be uniformly dispersed in the resin composition, and a more suitable conductive path can be formed. Furthermore, it is preferable also from a viewpoint which does not impair the fluidity of the resin composition containing a functional filler.
As a degree of spherical shape, the sphericity of the core particle is preferably, for example, 0.8 or more. Thereby, the dispersibility of the composite particles is improved to form a more preferable conductive path, and further, even if the functional filler is added, it is advantageous from the viewpoint of not impairing the fluidity of the resin composition.
In the present embodiment, the sphericity can be measured, for example, by the following method. First, core particles are dispersed in a resin such as an epoxy resin to cure the resin. Next, the surface of the cured resin is polished to expose core particles. Next, among the exposed core particles, 30 particles having a particle diameter of 0.5 to 2 times the D ₅₀ and overlapping or not in contact with other core particles are optionally observed. By this observation, the peripheral length l and the area S of the core particle are measured, and the circularity C is calculated for each of the 30 core particles according to the following formula. The average value of the circularity C of the 30 core particles can be made the sphericity of the core particles.
(Formula) Roundness C = 4πS / l ²

When the cumulative frequency of volume-based particle size distribution of the core particles is a particle diameter at which the 50% was _{D 50,} the lower limit of _{D 50,} for example, preferably at 0.01μm or more, 0.05 .mu.m or more Is preferably 0.1 μm or more. As a result, the frequency of defects in which the covering portion does not exist on the surface of the core particle can be reduced, interruption of the conductive path can be suppressed halfway, and the antistatic property and the antistatic property can be improved.
The upper limit of D ₅₀ of the core particle is, for example, preferably 50 μm or less, more preferably 30 μm or less, still more preferably 25 μm or less, and still more preferably 22 μm or less, It is particularly preferred that the thickness is 20 μm or less. As a result, the covering portions come close to each other, and a conductive path can be suitably formed.
In addition, D ₁₀ , D ₅₀ , and D ₉₀ , which are particle sizes at which the cumulative frequency of volume-based particle size distribution of the core particles according to this embodiment is 10%, 50%, and 90%, are measured by the following method, for example. it can. First, core particles are sufficiently dispersed in a solvent to prepare a dispersion. Next, the volume-based particle size distribution is measured using a laser diffraction / scattering particle size distribution measuring apparatus (for example, a particle size distribution measuring apparatus LA-920 manufactured by Horiba, Ltd.), and the cumulative frequency of the volume-based particle size distribution is 10%, The particle sizes of 50% and 90% can be made D ₁₀ , D ₅₀ and D ₉₀ respectively.

The upper limit value of the specific surface area of the core particles is not limited, and is, for example, preferably 30 m ² / cm ³ or less, more preferably 25 m ² / cm ³ or less, and 22 m ² / cm ³ or less Is more preferable, and 15 m ² / cm ³ or less is more preferable. The composite particle which concerns on this embodiment covers the surface of a core particle, and the coating | coated part which consists of carbon materials forms an electroconductive path when coating | coated parts adjoin. Here, when the specific surface area of the core particle is less than or equal to the above upper limit value, the frequency of defects in which the covering portion does not exist on the surface of the core particle can be reduced. As a result, it is possible to prevent the conduction path from being interrupted halfway, and the antistatic property and the antistatic property can be improved. Moreover, when a conductive path becomes difficult to be interrupted on the way, it is preferable also from a viewpoint which can improve antistatic property and antistatic property, without lowering | hanging a volume resistivity. For example, when a molded product is used as an electronic device, if there is a conductive portion, there is a disadvantage that the electrical reliability of the electronic device is lowered, but the antistatic property and antistatic property can be improved without lowering the volume resistivity. Case is preferable from the viewpoint of further improving the electrical reliability of the electronic device.
The lower limit value of the specific surface area of the core particles may be, for example, 0.5 m ² / cm ³ or more, or 1.0 m ² / cm ³ or more.
The specific surface area of the core particle according to the present embodiment is evaluated, for example, by calculating the surface area per unit volume of the core particle using the following formula from the volume-based particle size distribution calculated by the same method as D ₅₀ above. it can.
(Formula) Specific surface area [m ² / cm ³ ] = total surface area of core particles [m ² ] / total volume of core particles [cm ³ ]

In addition, you may use 2 or more types from which _D50 differs, for example, as a core particle which concerns on this embodiment. For example, when core particles having a large particle diameter and core particles having a small particle diameter are used in combination as core particles, the functional filler includes composite particles having a large particle diameter and composite particles having a small particle diameter. As a result, the composite particles are densely packed, so the content of the carbon material can be further reduced, and a conductive path can be formed. Therefore, it is preferable from the viewpoint of being able to improve the antistatic property and the antistatic property of the molded product without deteriorating the water absorbability and further reducing the volume resistivity.

(Carbonization process)
In the carbonization step, the organic resin is carbonized to obtain carbides by heat-treating the mixture obtained in the mixing step.
The heat treatment can be performed at a temperature at which the organic resin is carbonized. For example, the heat treatment may be performed at a maximum temperature of 500 ° C. or more and 700 ° C. or less.
Alternatively, for example, a first heat treatment at a maximum temperature of 500 ° C. to 700 ° C. and a second heat treatment at a maximum temperature of 1000 ° C. to 1300 ° C. may be included.
In the carbonization step, as the atmosphere for heat treatment, for example, an atmosphere reduced to an inert gas such as argon, nitrogen, carbon dioxide is preferable.

  In the carbonization step, the method of heat treatment is not limited as long as the method can uniformly heat treat. Specific examples of the heat treatment method include a roller house kiln, a rotary kiln, a vertical shaft kiln, a batch furnace, a spray pyrolysis apparatus, and a spray dry. In addition, you may use the apparatus which combined 2 or more types among the said specific examples as a method to heat-process.

(Carbon material)
The organic resin is carbonized by the carbonization step to become a carbon material.
As a carbon material, what contains amorphous carbon, for example is preferable, and what consists of amorphous carbon is more preferable. Thereby, the conductivity of the covering portion can be adjusted, and a more preferable conductive path can be formed.
In addition, it is preferable that the carbon material which concerns on this embodiment does not contain carbon black and diamond like carbon, for example. This makes it easy to form a uniform coating film on the core particles.
In the present embodiment, the carbon material made of amorphous carbon is subjected to powder X-ray diffraction measurement using a wide angle X-ray diffraction (WAXD) device for the carbon material, and the diffraction angle θ No peak indicating the presence of crystals is observed in the range of 2 ° to 80 °, which can be confirmed by showing only broad scattering.

As the carbon material, for example, one containing a nitrogen atom is preferable. Thereby, the coating can be made uniform, the adhesion between the coating portion and the core particles can be improved, and a suitable conductive path can be formed. In addition, the diffusion of static electricity can be improved, and the antistatic property can be improved. Furthermore, when it is set as a resin composition, the dispersibility of a functional filler with respect to resin can be improved, and it is preferable also from a viewpoint which can form a suitable conductive path.
In addition, the carbon material which concerns on this embodiment contains a nitrogen atom by using what contains an amino group called an aniline resin as an organic resin, for example.

Conventional fillers derived from natural raw materials such as carbon black contain, for example, sulfur compounds as impurities derived from the raw materials. Here, the functional filler according to the present embodiment is advantageous in that the sulfur compound derived from the raw material component is not contained.
The upper limit value of the sulfate ion concentration measured by hot water extraction of a sulfur compound in a carbon material is, for example, preferably 5.0 ppm or less, more preferably 3.0 ppm or less, and 2. It is more preferably 0 ppm or less, still more preferably 1.0 ppm or less, and particularly preferably 0.80 ppm or less. Thereby, it can suppress that impurities, such as a sulfuric acid compound derived from a functional filler, mix in a molding. When the functional filler according to the present embodiment is used as, for example, a molded product in contact with a metal member, corrosion of the metal member due to the sulfur compound can be suppressed. Specifically as a molding which contacts a metallic member, a resin composition for closure, etc. are mentioned. The sealing resin composition is used, for example, in contact with a metal member such as a copper circuit or a lead frame.
Moreover, as a lower limit of content of the sulfate ion measured by hot water extraction of the sulfur compound in a carbon material, 0 ppm or more may be sufficient and 0.01 ppm or more may be sufficient, for example. The smaller the content of sulfate ion in the carbon material, the more convenient it is because no impurities are mixed into the resin composition and the molded product.
The sulfate ion concentration according to the present embodiment can be measured, for example, as follows. First, the functional filler is weighed in a container, ultra pure water is added, and the container is sealed. Subsequently, hot water extraction is performed by heat-processing for 20 hours at the temperature of 125 degreeC using a thermostat. Next, the functional filler is removed from the solution obtained by the hot water extraction by centrifugation, filtration or the like to prepare a test solution. Next, for the test solution of the functional filler, the content of sulfate ion in the test solution is measured by a calibration curve method using a standard solution using an ion chromatography analyzer. The sulfate ion content of the functional filler used for the preparation of the test solution was taken as the sulfate ion concentration.

(Crushing process)
The method for producing a functional filler according to the present embodiment includes a crushing step of crushing carbide into composite particles after the carbonizing step. In addition, for example, when the carbide obtained in the carbonization step is sufficiently disintegrated to form composite particles, the crushing step may not be performed.
In the crushing step, the carbide obtained in the carbonizing step is broken into composite particles. The carbide is in a state in which a plurality of core particles are integrated by a carbon material, but the carbon material is crushed by crushing to obtain a plurality of composite particles. The functional filler may contain, for example, exfoliated carbon which is generated by exfoliation of the coated portion from the core particle by crushing.
The method of crushing is not limited, but specifically, impact-type pulverizing apparatus such as a ball mill, vibrating ball mill, rod mill, bead mill, vibrating sieve, etc .; cyclone mill, jet mill, dry air pulverizing machine, etc. And the like can be used. As a method of crushing, one of the above specific examples may be used, or an apparatus having two or more functions may be used.
In addition, as a method of using a vibrating screen, for example, a method of adding a carbide and an alumina ball to a vibrating screen and sifting may be mentioned. Thereby, the carbide can be crushed to produce composite particles having a desired particle size.
The crushing step may be performed, for example, in the presence of a cyclone classifier or a dust collector (bug filter). In this case, the composite particles are recovered by the cyclone classifier, and the exfoliated carbon not recovered is collected by the dust collector. Thereby, only exfoliated carbon can be selectively removed.

(Functional filler)
Hereinafter, the functional filler which concerns on this embodiment obtained by the manufacturing method of the functional filler mentioned above is demonstrated.
First, the functional filler according to the present embodiment includes, for example, a plurality of composite particles. The functional filler may further include, for example, the above-described release carbon.

(Composite particles)
The composite particle according to the present embodiment includes a carbon material and a core particle, and the surface of the core particle is provided with the covering portion made of the carbon material.
As a covering part, a part of core particles may be covered, and the whole surface of core particles may be covered. As the covering portion, for example, it is preferable to cover the entire surface of the core particle. This can reduce the frequency of defects without a coating on the surface of the core particle. Therefore, the conductive path can be prevented from being interrupted halfway, and the antistatic property and the antistatic property can be improved. Moreover, when a conductive path becomes difficult to be interrupted on the way, it is preferable also from a viewpoint which can improve antistatic property and antistatic property, without lowering | hanging a volume resistivity.
The layer structure of the composite particle is preferably, for example, a core-shell type structure in which the covering portion forms a shell layer and the core particle forms a core layer. Thereby, it can be set as the covering part which covers the core particle mentioned above over the whole surface. The shell layer may have, for example, pinholes generated by volatilization of the organic resin.

  The shape of the composite particle is not limited, and may be a shape according to the shape of the core particle. The shape of the composite particle can be, for example, a spherical shape, a scaly shape, a needle shape, or an irregular shape. The shape of the composite particles is preferably, for example, spherical. This is advantageous from the viewpoint of not impairing the flowability of the resin composition even if the functional filler is added.

(Peeling carbon)
The exfoliated carbon is made of, for example, a carbon material exfoliated from the coated portion of the composite particles, which is formed by the crushing step. Therefore, the exfoliated carbon is made of the same carbon material as the above-described carbon material.

The upper limit value of the volume resistivity of the functional filler according to this embodiment is, for example, preferably less than 1 × 10 ¹⁵ Ω · cm, more preferably less than 1 × 10 ¹³ Ω · cm, 1 More preferably, it is less than 10 ¹⁰ Ω · cm. As a result, while the surface of the core particle is sufficiently covered by the covering portion made of a carbon material, a covering portion with a uniform thickness can be formed. Therefore, a suitable conductive path can be formed by using a functional filler having a volume resistivity equal to or less than the above upper limit value.
The lower limit value of the volume resistivity of the functional filler according to the present embodiment is, for example, preferably 1 × 10 ⁵ Ω · cm or more, and more preferably 1 × 10 ⁷ Ω · cm or more. More preferably, it is 1 × 10 ⁹ Ω · cm or more. Thereby, when a molded article expresses antistatic property and antistatic property, it is convenient at a viewpoint which can control that electric discharges from a conductive part with high conductivity at once.
In addition, the volume resistivity of the functional filler which concerns on this embodiment can be measured by the method similar to the volume resistivity of the core particle mentioned above. Here, the upper limit lower limit value of the volume resistivity of the functional filler described above indicates the volume resistivity when a stress of 25.46 MPa is applied to the functional filler. Moreover, in this embodiment, as a condition which measures the volume resistivity of a functional filler, it is temperature 20 degreeC and humidity 40% RH similarly to the said core particle, for example.

The lower limit value of the carbon coverage of the functional filler according to the present embodiment is, for example, preferably 0.5 wt% or more, more preferably 1.0 wt% or more, and 1.5 wt% or more. Is more preferably 2.0 wt% or more, further preferably 2.5 wt% or more. Thereby, the surface of the core particle is sufficiently covered with the covering portion made of a carbon material. Therefore, a suitable conductive path can be formed by using a functional filler having a carbon coverage of not less than the above lower limit value.
The upper limit of the carbon coverage of the functional filler according to this embodiment is, for example, preferably 30 wt% or less, more preferably 25 wt% or less, and still more preferably 20 wt% or less. . Thereby, it can suppress that the conductive path which a functional filler forms breaks on the way, and it can improve antistatic property and antistatic property. Moreover, when a conductive path becomes difficult to be interrupted on the way, it is preferable also from a viewpoint which can improve antistatic property and antistatic property, without lowering | hanging a volume resistivity.
The carbon coating amount according to the present embodiment can be, for example, a weight reduction rate when the functional filler is heat treated in air at a temperature of 900 ° C. for 1 hour. Here, the weight reduction rate can be calculated by the following equation, where A is the mass of the functional filler before heat treatment, and B is the mass of the functional filler after heat treatment.
(Formula) Weight reduction rate [wt%] = (A−B) / A × 100
In addition, the carbon coating amount which concerns on this embodiment can be controlled by selecting factors, such as a kind of organic resin, and addition amount, appropriately, for example.

The upper limit value of the moisture absorption rate of the functional filler according to the embodiment is, for example, preferably 7.0 wt% or less, more preferably 5.0 wt% or less, and 1.0 wt% or less Is more preferred. Thereby, when it is set as a molding, it can suppress degrading water absorbency.
Moreover, as a lower limit of the moisture absorption rate of the functional filler which concerns on this embodiment, 0 wt% or more may be sufficient, for example, and 0.0001 wt% or more may be sufficient. This allows the surface of the core particle to be coated with a sufficient amount of carbon material to form a suitable conductive path.
In the present embodiment, the moisture absorption rate is calculated by the following equation, where X represents the mass of the functional filler before the moisture absorption treatment after drying processing, and Y represents the mass of the functional filler after the moisture absorption treatment.
(Formula) Moisture absorption rate [wt%] = {(Y-X) / X} x 100
The drying process is performed under the conditions of vacuum drying the functional filler at a temperature of 120 ° C. for 12 hours. The moisture absorption treatment is performed under the condition that the dried functional filler is held for 1 week in a high temperature and high humidity tank under a constant condition of temperature 40 ° C. and humidity 90% RH.

(Granulation filler)
The functional filler according to the present embodiment can be used as a granulation filler, for example, by granulating and combining a plurality of composite particles into one. That is, the granulated filler which concerns on this embodiment granulates a functional filler, for example.
The method for granulation is not limited, and a conventionally known method can be used. As a method of granulating, for example, a method of making a varnish in which a functional filler is dispersed in a liquid mixture consisting of a solvent such as water and ethanol and a resol type phenol resin, and then using the method of volatilizing the solvent, etc. Can.

  As an apparatus for granulating, a high performance powder processing apparatus can be used. Specifically, as a commercial product of the high-performance powder processing apparatus, use a spray dryer manufactured by Ogawara Kakohki Co., Ltd., a granulating mixer manufactured by Nippon Coke Kogyo Co., Ltd., a dry particle composite apparatus Novirta manufactured by Hosokawa Micron Corporation, etc. Can.

(Carburized filler)
The granulated filler according to the present embodiment can be used as a carbonized filler, for example, by heat treatment and carbonizing the resin used for granulation. That is, the carbonized filler according to the present embodiment is formed by carbonizing the granulated filler.
By using a carbonized filler, control of the phase structure using composite particles can be performed. Thereby, the flowability of the resin composition can be further improved as compared with fine composite particles. Further, the phase structure constituted by the carbon material and the core particles can be more precisely controlled, and the controllability of the conductive path can be improved.
In addition, you may perform the process of carbonizing a granulated filler on the same conditions as the carbonization process of the functional filler which concerns on this embodiment, for example. In addition, after the carbonization step, for example, the crushing may be performed under the same conditions as the crushing step of the functional filler according to the present embodiment.

(Use)
The functional filler, the granulated filler, and the carbonized filler according to the present embodiment can be used as a resin composition, for example, by being contained in a resin. That is, the resin composition according to the present embodiment contains a functional filler, a granulated filler or a carbonized filler, and a resin.
In addition, the resin composition according to the present embodiment can be molded and used as a molded product. That is, the molded product according to the present embodiment is formed by molding a resin composition.

The functional filler according to the present embodiment can develop properties that can not be realized by the conventional filler when dispersed in a molded product, and thus can be developed into various applications.
In addition to the antistatic property and the antistatic property described above, for example, by using a conductive path made of a carbon material as a heat dissipation path, it is possible to exhibit the function of improving the heat dissipation characteristics. In order to improve such heat radiation characteristics, specifically, it can be used for a heat conductive sheet, a paste-like resin composition, a powder coating material, etc. to be interposed between a heat generating body and a heat radiating body.
Furthermore, for example, by using an electromagnetic wave shielding material or metal such as sendust or ferrite as the core particle, a function as an electromagnetic wave shielding property can be provided. When a metal is used as the core particle, the functional filler according to the present embodiment is preferable from the viewpoint of maintaining the electrical insulating property, setting the volume resistivity to an appropriate numerical range, and further exhibiting the electromagnetic wave shielding property.
In addition, the functional filler according to the present embodiment includes composite particles including a covering portion made of a carbon material, and exfoliated carbon, for example. Thereby, the color of the functional filler according to the present embodiment is black. Therefore, the functional filler according to the present invention may be used in combination with a colorant, a colorant, a pigment or a dye, or may be used as a substitute for a colorant, a colorant, a pigment or a dye.

The application of the molded article according to the present embodiment is not limited, and can be mixed with any molded article formed by the resin composition.
Specifically, moldings used for electronic devices such as semiconductor packages, smartphones, inductors, and in-vehicle electronic devices; tire members such as inner liners and belts; vehicle parts such as door trims, rotor cores, and brake pads And moldings used for

  The functional filler according to the present embodiment is convenient from the viewpoint of being able to suppress charging, even when it is used for a molded product that is in frequent contact with other substances. Specific examples of such a molded article that frequently contacts with other substances include friction materials such as brake pads, mold members such as mold release films, members that accommodate electronic devices such as cover tapes, and decorative plates Building materials such as

  Below, the aspect used as a resin composition for sealing for sealing the electronic element of an electronic device as an example of a resin composition is demonstrated.

(Resin composition for sealing)
Examples of the sealing resin composition according to the present embodiment include those containing an epoxy resin, a curing agent, and the functional filler according to the present embodiment.

(Epoxy resin)
As the epoxy resin, regardless of its molecular weight and molecular structure, it is possible to use monomers, oligomers and polymers in general having two or more epoxy groups in one molecule. Specific examples of such an epoxy resin include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol E epoxy resin, bisphenol S epoxy resin, hydrogenated bisphenol A epoxy resin, bisphenol M epoxy resin (4 4,4 '-(1,3-phenylenediisoprediene) bisphenol-type epoxy resin), bisphenol P-type epoxy resin (4,4'-(1,4-phenylenediisoprediene) bisphenol-type epoxy resin), bisphenol Bisphenol type epoxy resin such as Z type epoxy resin (4,4′-cyclohexydiene bisphenol type epoxy resin); phenol novolac type epoxy resin, brominated phenol novolac type epoxy resin, cresol novolac type epoxy resin, Novolak type epoxy resin such as laporol ethane type novolac epoxy resin, novolac type epoxy resin having condensed ring aromatic hydrocarbon structure; biphenyl type epoxy resin; aralkyl type epoxy resin such as xylylene type epoxy resin, biphenylaralkyl type epoxy resin Resins: Naphthylene ether type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, naphthalenediol type epoxy resin, difunctional to tetrafunctional epoxy type naphthalene resin, binaphthyl type epoxy resin, naphthalene skeleton such as naphthalene aralkyl type epoxy resin Epoxy resin having anthracene type epoxy resin phenoxy type epoxy resin dicyclopentadiene type epoxy resin norbornene type epoxy resin adamantane type epoxy resin Fluorene type epoxy resin, phosphorus containing epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, bisphenol A novolac type epoxy resin, bixylenol type epoxy resin, triphenolmethane type epoxy resin, trihydroxyphenylmethane type epoxy resin And heterocyclic epoxy resins such as tetraphenylol ethane type epoxy resin and triglycidyl isocyanurate; N, N, N ', N'-tetraglycidyl metaxylene diamine, N, N, N', N'-tetraglycidyl bis Glycidyl amines such as aminomethylcyclohexane, N, N-diglycidyl aniline, etc., copolymer of glycidyl (meth) acrylate and a compound having an ethylenically unsaturated double bond, epoxy resin having a butadiene structure, diglycidyl of bisphenol It can include ether compound, diglycidyl ethers of naphthalene diol, the one or more selected from glycidyl ethers of phenols.

(Hardening agent)
Specific examples of the curing agent include three types of curing agents of polyaddition type, curing agents of catalytic type, and curing agents of condensation type.

  Specifically, polyaddition-type curing agents used as the above-mentioned curing agent are aliphatic polyamines such as diethylenetriamine (DETA), triethylenetetramine (TETA), metaxylylenediamine (MXDA), diaminodiphenylmethane (DDM) And polyamine compounds including dicyandiamide (DICY), organic acid dihydrazide, etc. in addition to aromatic polyamines such as m-phenylenediamine (MPDA) and diaminodiphenylsulfone (DDS); hexahydrophthalic anhydride (HHPA), methyltetrahydrophthalic anhydride Acid anhydrides including alicyclic acid anhydrides such as (MTHPA), trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), aromatic acid anhydrides such as benzophenone tetracarboxylic acid (BTDA), etc .; Novolak Type fe Phenolic resin-based curing agents such as polyvinyl chloride and aralkyl type phenolic resins; polymercaptan compounds such as polysulfides, thioesters and thioethers; isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; carboxylic acid-containing polyester resins etc. Be As the polyaddition type curing agent, one or more types selected from the above specific examples can be included.

  Specifically, the catalyst type curing agent used as the above curing agent is a tertiary amine compound such as benzyldimethylamine (BDMA) or 2,4,6-trisdimethylaminomethylphenol (DMP-30); 2- And imidazole compounds such as methylimidazole and 2-ethyl-4-methylimidazole (EMI 24); and Lewis acids such as BF3 complex. The catalyst type curing agent may include one or more selected from the above specific examples.

  Specific examples of the condensation type curing agent used as the curing agent include resol type phenol resins; urea resins such as methylol group-containing urea resins; and melamine resins such as methylol group-containing melamine resins. The condensation type curing agent may include one or more selected from the above specific examples.

Among the above-mentioned curing agents, it is preferable to contain a phenol resin-based curing agent.
As a phenol resin-based curing agent, monomers, oligomers and polymers all having two or more phenolic hydroxyl groups in one molecule can be used, and the molecular weight and molecular structure thereof are not limited.
Specific examples of the phenol resin-based curing agent used as the curing agent include novolac type phenolic resins such as phenol novolac resin, cresol novolac resin, bisphenol novolac and phenol-biphenyl novolac resin; polyvinyl phenol; triphenylmethane type phenolic resin etc. Multifunctional phenolic resins; modified phenolic resins such as terpene-modified phenolic resins and dicyclopentadiene-modified phenolic resins; phenolic aralkyl resins having a phenylene skeleton and / or a biphenylene skeleton, naphthol aralkyl resins having a phenylene and / or a biphenylene skeleton, etc. Phenol aralkyl type phenol resin; bisphenol compounds such as bisphenol A, bisphenol F, etc. may be mentioned. The phenolic resin-based curing agent can include one or more selected from the above specific examples.

In the sealing positive resin composition, if necessary, various fillers such as fillers other than functional fillers, a curing accelerator, a coupling agent, a mold release agent, a flame retardant, an ion scavenger, a coloring agent, a low stress agent, etc. One or more of the additives may be blended.
The representative components are described below.

(Filling material)
Examples of the filler include silica such as fused and crushed silica, fused spherical silica, crystalline silica, secondary aggregation silica, alumina, titanium white, aluminum hydroxide, talc, clay, mica, glass fiber and the like.

(Hardening accelerator)
The resin composition for sealing may further contain a curing accelerator. The curing accelerator may be any one that accelerates the curing reaction between the epoxy group and the curing agent.
Specific examples of the curing accelerator include diazabicycloalkenes such as 1,8-diazabicyclo [5.4.0] undecene-7 and derivatives thereof; amine compounds such as tributylamine and benzyldimethylamine; -Imidazole compounds such as methylimidazole; organic phosphines such as triphenylphosphine and methyl diphenylphosphine; tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetrabenzoic acid borate, tetraphenylphosphonium tetranaphthoic acid borate, tetraphenyl Tetra-substituted phosphonium tetra-substituted borates such as phosphonium tetra-naphthoyl oxyborate, tetraphenyl phosphonium tetra-naphthyl oxyborate, etc .; adducts of benzoquinone Triphenylphosphine and the like. As a hardening accelerator, it can be used combining 1 type, or 2 or more types among the said specific examples.

(Coupling agent)
The sealing resin composition may further contain a coupling agent.
As the coupling agent, specifically, epoxy silane coupling agent, cationic silane coupling agent, aminosilane coupling agent, γ-glycidoxypropyltrimethoxysilane coupling agent, γ-aminopropyltriethoxysilane cup Ring agents, γ-mercaptopropyltrimethoxysilane coupling agents, N-phenyl-γ-aminopropyltrimethoxysilane coupling agents, silane coupling agents such as mercaptosilane coupling agents, titanate coupling agents and silicone oil types Coupling agents and the like can be mentioned. As a coupling agent, it can be used combining 1 type, or 2 or more types among the said specific examples.

(Release agent)
The sealing resin composition may further contain a release agent.
Specific examples of the releasing agent include natural waxes such as carbanana wax; synthetic waxes such as montanic acid esters; higher fatty acids or metal salts thereof; paraffins; oxidized polyethylene and the like. As a mold release agent, it can be used combining 1 type, or 2 or more types among the said specific examples.

(Flame retardants)
The sealing resin composition may further contain a flame retardant.
Specific examples of the flame retardant include magnesium hydroxide, zinc borate, zinc molybdate, phosphazene and the like. As a flame retardant, it can be used combining 1 type, or 2 or more types among the said specific examples.

(Colorant)
The sealing resin composition may further contain a colorant.
Specific examples of the colorant include carbon black, bengala, titanium oxide and the like. As a coloring agent, 1 type (s) or 2 or more types can be mix | blended among the said specific examples.

(Ion capture agent)
The resin composition for sealing may further contain an ion scavenger.
Specific examples of the ion scavenger include hydrotalcite; zeolite; and hydrous oxides of elements selected from magnesium, aluminum, bismuth, titanium and zirconium. As an ion capture agent, it can be used combining 1 type, or 2 or more types among the said specific examples.

(Low stress agent)
The sealing resin composition may further contain a low stress agent.
Specific examples of the low stress agent include polybutadiene compounds, acrylonitrile butadiene copolymer compounds, silicone oils such as silicone oil and silicone rubber, and the like. As the low stress agent, one or more of the above specific examples can be used in combination.

The lower limit value of the content of the filler in the sealing resin composition is, for example, preferably 50 parts by mass or more, and 60 parts by mass or more with respect to 100 parts by mass of the solid content of the sealing resin composition. Is more preferably 70 parts by mass or more.
In addition, the upper limit value of the content of the filler in the sealing resin composition is, for example, preferably less than 95 parts by mass, and not more than 93 parts by mass with respect to the solid content of the sealing resin composition. The content is more preferably 90 parts by mass or less.
The lower limit of the content of the functional filler in the filler is, for example, preferably 1 part by mass or more, more preferably 2 parts by mass or more, with respect to 100 parts by mass of the filler. It is more preferable that it is more than a mass part. Thereby, a suitable conductive path can be formed.
In addition, the upper limit value of the content of the functional filler in the filler is, for example, preferably 100 parts by mass or less, more preferably 50 parts by mass or less, with respect to 100 parts by mass of the filler. More preferably, it is at most 10 parts by mass, and more preferably at most 10 parts by mass.

  Next, an electronic device using the sealing resin composition according to the present embodiment will be described.

  The resin composition for sealing which concerns on this embodiment is used for the sealing resin layer which seals an electronic device. Although the method to form a sealing resin layer is not limited, For example, a transfer molding method, a compression molding method, injection molding etc. are mentioned. The sealing resin layer can be formed by molding and curing the sealing resin composition by these methods.

The electronic device is preferably, but not limited to, a semiconductor device.
Examples of the semiconductor device include, but are not limited to, integrated circuits, large scale integrated circuits, transistors, thyristors, diodes, and solid-state imaging devices.
Among these, as a semiconductor element in which the resin composition for sealing of this embodiment is useful, it is a semiconductor element in which the metal part is exposed. Thereby, the corrosion of the metal portion can be suppressed. A transistor is mentioned as a semiconductor element in which such a metal part is exposed. Among the transistors, the sealing resin composition of this embodiment can be effectively used for sealing a MIS transistor in which a gate electrode is exposed.

  If electrical connection between the electronic element and the base material is required, connection may be made as appropriate. Although the method of electrically connecting is not limited, for example, wire bonding, flip chip connection and the like can be mentioned. Among these, as a semiconductor element in which the resin composition for sealing of this embodiment is useful, it is a semiconductor element in which the metal part is exposed. Thereby, the corrosion of the metal portion can be suppressed. An electrical connection method in which such a metal portion is exposed includes wire bonding.

An electronic device is obtained by forming a sealing resin layer for sealing an electronic element with the sealing resin composition. The electronic device is not limited, but is preferably a semiconductor device obtained by molding a semiconductor element.
Specific examples of semiconductor devices include MAP (Mold Array Package), QFP (Quad Flat Package), SOP (Small Outline Package), CSP (Chip Size Package), QFN (Quad Flat Non-leaded Package), SON (Small Outline Non-leaded Package), BGA (Ball Grid Array), LF-BGA (Lead Flame BGA), FCBGA (Flip Chip BGA), MAPBGA (Molded Array Process BGA), eWLB (Embedded Wafer-Level BGA), Types such as Fan-In type eWLB and Fan-Out type eWLB Be

  As mentioned above, although embodiment of this invention was described, these are the illustrations of this invention, and various structures other than the above can also be employ | adopted.

Hereinafter, the present invention will be described in detail using examples, but the present invention is not limited to the description of these examples.
First, raw material components used in Examples 1 to 5 and Comparative Examples 1 to 4 will be described.

(Core particle)
As core particles of Examples 1 to 5 and Comparative Examples 1 to 4, core particles 1 to 4 shown in Table 1 below were used.

(Particle size distribution, specific surface area)
The particle size distribution D ₁₀ , D ₅₀ and D _{90 of} the core particles and the specific surface area were measured by the following method.
First, 20 mg of core particles were dispersed in a mixed solution of 1 ml of surfactant (manufactured by Kishida Chemical Co., Ltd., Tween 20) diluted to 1 wt% and about 5 ml of distilled water to obtain a dispersion. Dispersion was carried out using an ultrasonic cleaner and was carried out by stirring while applying ultrasonic waves for 1 minute. The volume-based particle size distribution of the dispersion was measured using a particle size distribution measuring apparatus (particle size distribution measuring apparatus LA-920, manufactured by Horiba, Ltd.). In the particle size distribution measurement apparatus, the relative refractive index of silica is 1.09, the relative refractive index of alumina is 1.25, and the relative refractive index of carbon black is 1.5.
The particle sizes at which the cumulative frequency of the obtained volume-based particle size distribution is 10%, 50%, and 90% are respectively D ₁₀ , D ₅₀ , and D ₉₀ . The unit is μm.
Moreover, the surface area per unit volume of core particles was calculated as a specific surface area from the volume-based particle size distribution using the following formula. The unit is m ² / cm ³ .
(Formula) Specific surface area [m ² / cm ³ ] = total surface area [m ² ] / total volume [cm ³ ]

(Sphericity)
Moreover, the measurement of the sphericity of core particles was measured as follows. The core particles were dispersed in the epoxy resin composition and the epoxy resin composition was cured. Next, the surface of the epoxy resin composition was polished to expose core particles. Among the exposed core particles, 30 particles having a particle diameter of not less than 0.5 times and not more than 2 times the above D ₅₀ and overlapping or not in contact with other core particles were optionally observed. The observation was performed using a high performance image analysis system (IP-500PC, manufactured by Asahi Engineering Co., Ltd.). From this observation, the perimeter length l and the area S of the core particles were measured, and the circularity C was calculated for each of the 30 core particles according to the following equation. The average value of the circularity C of the 30 core particles was evaluated as the sphericity of the core particles. The unit is dimensionless. In addition, since the degree of circularity can not be calculated for core particles whose shape is not spherical, evaluation of sphericity is not performed.
(Formula) Roundness C = 4πS / l ²

(Volume resistivity)
Moreover, the volume resistivity of core particles was measured by the following method.
Using the powder resistance measurement system (MCP-PD 51, 10.0 mm radius counter electrode probe) and the resistivity meter (Hiresta-UX, manufactured by Mitsubishi Chemical Analytech Co., Ltd.), the core particles are used as the core particles in the above table. The load shown in 1 and an applied voltage were applied to measure the resistance, and the volume resistivity was calculated from the resistance. The unit is Ω · cm.
In addition, the measurement was performed using the sample of the quantity used as about 2 mm in thickness at 20 kN of loads. Moreover, the measured value was taken 20 seconds after pressing the measurement start button.
The measurement limit of the volume resistivity of the resistivity meter used in this measurement is 1 × 10 ³ Ω · cm or more and less than 1 × 10 ¹⁵ Ω · cm. For example, since any load of the volume resistivity of the core particle 4 was less than the measurement lower limit, it is shown as “<1.0 × 10 ³ ”.
In addition, the measurement was performed about the load of 4 kN, 8 kN, 12 kN, 16 kN, 20 kN. The pressure when each load is applied corresponds to 12.73 MPa, 25.46 MPa, 38.20 MPa, 50.93 MPa, 63.66 MPa, respectively.
The measurement of the volume resistivity was performed under the conditions of a temperature of 20 ° C. and a humidity of 40% RH.

(Organic resin)
As the organic resin of Examples 1 to 5 and Comparative Example 3, an organic resin 1 which is an aniline resin was synthesized and used. Specifically, 100 parts by mass of aniline, 697 parts by mass of 37% aqueous formaldehyde solution, and 2 parts by mass of oxalic acid are placed in a three-necked flask equipped with a stirrer and a condenser, and reacted for 3 hours at a temperature of 100 ° C. After dewatering. Thus, 110 parts by mass of aniline resin as an organic resin was obtained. The organic resin 1 was liquid at a temperature of 300.degree.

Example 1
The manufacturing method of the functional filler of Example 1 is demonstrated.
Each raw material component of the compounding quantity described in following Table 3 was grind | pulverized and mixed with the vibration ball mill, and the resin composition was produced. Next, the resin composition was heat-treated to obtain a carbon material, and a carbide in which the carbon material was attached to the surface of the core particle was obtained. The carbon material attached to the surface of the core particle forms a coated portion of the composite particle. The heat treatment was performed by raising the temperature from room temperature to 580 ° C. at a temperature rising rate of 100 ° C./hour in a nitrogen atmosphere using a medium-sized batch furnace and holding the temperature at 580 ° C. for 1.5 hours.
Next, the carbide and a plurality of alumina balls (diameter 10 mm) are put in a 45 μm mesh sieve, and the carbide is partially crushed by sieving using a vibrating sieve to coarsely grow particles It removed and was set as the composite particle provided with the coating | coated part which consists of carbon materials on the surface of core particle. Thereby, the functional filler concerning Example 1 comprised by several composite particle | grains was obtained.

(Examples 2 to 3)
Functional fillers of Examples 2 to 3 were prepared under the same conditions as in Example 1 except that the blending amounts of the respective raw material components were changed as shown in Table 3 below, and the conditions for crushing the carbide were changed as follows. Obtained.
The carbides according to Examples 2 to 3 were subjected to two-stage crushing using a cyclone milling device and a vibrating screen.
First, using the cyclone mill pulverizer (dry pulverizer, manufactured by Shizuoka Plant, 150 BMW type cyclone mill), the carbide according to Examples 2 to 3 was supplied with a powder feed amount of 50 g / min, air volume of 0.5 m ³ / min, The crushing was performed under the conditions of the first crushing impeller rotational speed 15000 rpm and the second crushing impeller rotational speed 15000 rpm, and crushed materials according to Examples 2 to 3 were obtained.
Subsequently, the crushed material obtained by the cyclone milling device and a plurality of alumina balls (diameter 10 mm) are put in a sieve with an opening of 45 μm, and sieved using a vibrating sieve to form a composite particle. The functional filler concerning Example 2-3 was obtained.

(Examples 4 to 5)
The functional filler of Examples 4-5 was obtained on the conditions similar to Example 1 except having changed the compounding quantity of each raw material component like following Table 3.

(Comparative example 1)
The core particle 1 was used as a functional filler according to Comparative Example 1.

(Comparative example 2)
The core particle 2 was used as a functional filler according to Comparative Example 2.

(Comparative example 3)
The manufacturing method of the functional filler of the comparative example 3 is demonstrated.
The functional filler of the comparative example 3 was produced by the method similar to Examples 2-3 except having changed the compounding quantity of each raw material component like following Table 3, and having not used core particle | grains. Specifically, the organic resin was carbonized into a carbon material, and the carbon material was crushed in two steps using a cyclone mill pulverizer and a vibrating sieve to obtain a functional filler of Comparative Example 3. Therefore, the functional filler of Comparative Example 3 is made of a carbon material.
Various physical properties of the functional filler of Comparative Example 3 are shown in Table 2 below. _{Incidentally, D 10, D 50, D} 90, the specific surface area, sphericity, volume resistivity was performed by the same method as the measurement of the above-mentioned core particles. _{Here, D 10, D 50, D} 90, the relative refractive index in the measurement of specific surface area was 1.5.

(Comparative example 4)
The core particle 4 was used as a functional filler according to Comparative Example 4.

<Evaluation of functional filler>
The following evaluation was performed about the functional filler of Examples 1-5 and Comparative Examples 1-4.

(Particle size distribution of functional filler, specific surface area)
Examples 1-5, the functional filler of Comparative Examples 1 to 4, a particle size distribution _{D 10, D 50, D 90} , were evaluated specific surface area. The evaluation method is the same as the evaluation method of the particle size distribution D ₁₀ , D ₅₀ , D _{90 of} the core particles described above and the specific surface area. The evaluation results are shown in Table 3 below.
In addition, the relative refractive index of the functional filler of Examples 1-4 was 1.09, and the relative refractive index of the functional filler of Example 5 was 1.25.

(Content of nitrogen atom)
About the functional filler of Examples 1-5 and Comparative Examples 1-4, content of the nitrogen atom in a carbon material was evaluated. Details will be described below.
About the functional filler of each Example and each comparative example, the nitrogen content in a carbon material was evaluated using an elemental analyzer (analysis method: a combustion method, Sumika Analysis Center company make, Sumigraph). The evaluation results are shown in Table 3 below. In addition, a unit is% and shows the percentage of content of the nitrogen atom with respect to a carbon material.

(Carbon coating amount)
The carbon coverage of the composite particles was evaluated for the functional fillers of Examples 1 to 5. Details will be described below.
First, 3.0 g of the functional filler of each example was weighed in a crucible. Next, heat treatment was performed at a temperature of 900 ° C. for 1 hour in an air atmosphere using a muffle furnace. Here, assuming that the mass of the functional filler before heat treatment is A and the mass of the functional filler after heat treatment is B, the weight reduction rate calculated by the following equation is the carbon coverage of the coating portion on the composite particles Calculated. The evaluation is shown in Table 3 below. The unit is wt%.
(Formula) Weight reduction rate [wt%] = (A−B) / A × 100

(Crystallinity of carbon material)
About the functional filler of Examples 1-5 and Comparative Example 3, it confirmed that a carbon material did not contain crystalline carbon but was constituted only with amorphous carbon. Details will be described below.
The functional fillers of Examples 1 to 5 and Comparative Example 3 were subjected to powder X-ray diffraction measurement using a wide-angle X-ray diffractometer to obtain X-ray profiles. Here, the measurement was performed in the range of θ = 2 ° to 80 °. As a result of the measurement, in the X-ray profiles of Examples 1 to 5 and Comparative Example 3, no peak indicating the presence of crystals was observed, and only broad scattering was shown. Therefore, it was confirmed that in the functional fillers of Examples 1 to 5 and Comparative Example 3, the carbon material does not contain crystalline carbon and is constituted only by amorphous carbon.

(Observation of functional filler)
The structure of the functional filler of Examples 1-5 was observed. Details are shown below.
First, composite particles of the functional filler of Examples 1 to 5 were observed using a transmission electron microscope (TEM). As an example, TEM photographs of the functional filler of Example 2 are shown in FIGS. 1 and 2 are TEM photographs of different fields of view, respectively. Thereby, it was confirmed that the composite particle which constitutes the functional filler of Examples 1-5 equips the surface of core particle with the covering part which consists of carbon materials. In addition, it was confirmed that in the layer structure of the composite particles, the covering portion forms a shell layer and covers the core particles. Furthermore, it was confirmed that the shape of the composite particles is spherical.

(Sulfate ion concentration of functional filler)
The sulfate ion concentration of the functional fillers of Examples 1 to 5 and Comparative Examples 3 to 4 was measured. Details will be described below.
First, 2.0 g of the functional fillers of Examples 1 to 5 and Comparative Examples 3 to 4 were weighed in a container, and 40 ml of ultrapure water was added to seal the container. Subsequently, hot water extraction was performed by heat-processing for 20 hours at the temperature of 125 degreeC using a thermostat. Then, after cooling to room temperature, the mixed solution of the functional filler and the ultrapure water was centrifuged, and then filtered with a filter of 0.5 μm aperture to obtain a test solution. Next, the content of sulfate ion in the test solution is measured by a calibration curve method using a standard solution using an ion chromatography analyzer. The sulfate ion content of the functional filler used for the preparation of the test solution was taken as the sulfate ion concentration. The unit is ppm.

(Volume resistivity of functional filler)
The volume resistivity was measured about the functional filler of Examples 1-5 and Comparative Examples 1-4. The evaluation method is the same as the evaluation method of the volume resistivity of the core particle described above. The measurement environment was a temperature of 20 ° C. and a humidity of 40% RH. The load applied at the time of measurement, applied voltage and evaluation results are shown in Table 3 below. The unit is Ω · cm.

(Water absorption rate of functional filler)
The moisture absorption rate was measured about the functional filler of Examples 1-5 and Comparative Examples 1-4. Details will be described below.
First, 3.0 g of the functional fillers of Examples 1 to 5 and Comparative Examples 1 to 4 were weighed into petri dishes, and used as measurement samples. Next, for the purpose of removing water prior to measurement, a drying process was performed in which the measurement sample was vacuum dried at a temperature of 120 ° C. for 12 hours. Subsequently, the moisture absorption process which hold | maintains a measurement sample for one week was performed in the high temperature and high humidity tank of the conditions of temperature 40 degreeC and humidity 90% RH.
Assuming that the mass of the measurement sample before the moisture absorption treatment is X and the mass of the measurement sample after the moisture absorption treatment is Y after the drying process, the moisture absorption rate is calculated by the following equation. The evaluation results are shown in Table 3 below. The unit is wt%.
(Formula) Moisture absorption rate [wt%] = {(Y-X) / X} x 100

<Resin composition for sealing>
The resin composition for sealing was produced as a resin composition using the functional filler of each Example and each comparative example which were mentioned above.
First, raw material components used for the sealing resin composition are shown below.

(Epoxy resin)
Epoxy resin 1: Biphenyl type epoxy resin (Mitsubishi Chemical Co., YX4000K)
Epoxy resin 2: Phenolic aralkyl type epoxy resin having a biphenylene skeleton (manufactured by Nippon Kayaku Co., Ltd., NC 3000)

(Hardening agent)
Hardener 1: Triphenylmethane-type phenol resin modified with formaldehyde (Air Water, HE 910-20)
Hardener 2: Phenolic aralkyl resin having a biphenylene skeleton (manufactured by Nippon Kayaku Co., Ltd., GPH-65)

(Filling material)
· Filler 1: alumina (manufactured by Micron, AX3-20AR, D ₅₀ = 4 μm)

(Functional filler)
-Functional filler 1: The functional filler of Example 1 was used as the functional filler 1.
-Functional filler 2: The functional filler of Example 2 was used as the functional filler 2.
-Functional filler 3: The functional filler of Example 3 was used as the functional filler 3.
-Functional filler 4: The functional filler of Example 4 was used as the functional filler 4.
-Functional filler 5: The functional filler of Example 5 was used as the functional filler 5.
Functional filler 6: The functional filler of Comparative Example 1 was used as the functional filler 6.
-Functional filler 7: The functional filler of Comparative Example 2 was used as the functional filler 7.
-Functional filler 8: The functional filler of Comparative Example 3 was used as the functional filler 8.
-Functional filler 9: The functional filler of Comparative Example 4 was used as the functional filler 9.

(Coupling agent)
Coupling agent 1: N-phenyl-3-aminopropyltrimethoxysilane (Toray Dow Corning, CF4083)

(Release agent)
-Releasing agent 1: Montanic acid ester wax (manufactured by Clariant Japan, Recolb WE-4)

(Ion capture agent)
・ Ion trapping agent 1: Hydrotalcite (Kyowa Chemical Industry, DHT-4H)

Curing Accelerator 1: An adduct of a phosphonium compound represented by the following formula (P1) and a silane compound was synthesized and used as a curing accelerator 1. The details of the synthesis method will be described below.
First, 249.5 g of phenyltrimethoxysilane and 384.0 g of 2,3-dihydroxynaphthalene are added to a flask containing 1800 g of methanol and dissolved, and then 231.5 g of a 28% sodium methoxide-methanol solution is added dropwise while stirring at room temperature. did. Next, a solution of 503.0 g of tetraphenylphosphonium bromide in 600 g of methanol was dropped into a flask under stirring at room temperature to precipitate crystals. The precipitated crystals were filtered, washed with water and vacuum dried to obtain a curing accelerator 1 which is a pinkish white crystal of an adduct of a phosphonium compound and a silane compound.

(Low stress agent)
・ Low stress agent 1: Silicone oil having polyalkylene ether group, methyl group etc. (manufactured by Toray Dow Corning, FZ-3730)

(Preparation of sealing resin composition)
Each component of the compounding quantity described in the following Table 4 was mixed using a mixer at normal temperature, and then biaxially kneaded at a temperature of 70 ° C. or more and 100 ° C. or less. Subsequently, after cooling to normal temperature, it grind | pulverized and obtained the resin composition for sealing which concerns on Examples 6-10 and Comparative Examples 5-8.

<Evaluation of sealing resin composition>
The following evaluation was performed about the resin composition for sealing which concerns on each Example and each comparative example, and its molded article.

(Liquidity)
Using a low-pressure transfer molding machine (KTS-30, manufactured by Kotaki Seiki Co., Ltd.), mold temperature for spiral flow measurement according to EMMI-1-66, mold temperature 175 ° C., injection pressure 6.9 MPa, pressure holding time The sealing resin compositions according to Examples 6 to 10 and Comparative Examples 5 to 8 were injected and cured under the conditions of 120 seconds, and the spiral flow was measured. The unit of spiral flow is cm. The fluidity was evaluated based on the following evaluation criteria from the value of the obtained spiral flow. The evaluation results are shown in Table 4 below.
○: Spiral flow was 100 cm or more.
X: Spiral flow was less than 100 cm.

(Water absorption rate)
Examples 6 to 10, Comparative Examples 5 to 8 using a low-pressure transfer molding machine (KTS-30 manufactured by Kotaki Seiki Co., Ltd.) under the conditions of a mold temperature of 175 ° C., an injection pressure of 7.4 MP and a curing time of 120 seconds. The injection molding of the sealing resin composition according to the above to a diameter of 50 mm and a thickness of 3 mm, and post curing at 175 ° C. for 4 hours produced a test piece. Then, the test piece was boiled in pure water for 24 hours. The percentage of the mass of the test piece after boiling treatment to the mass of the test piece before boiling treatment was taken as the water absorption rate. The evaluation results are shown in Table 4 below. The unit is wt%.

(Volume resistivity)
In Examples 6 to 10 and Comparative Examples 5 to 8 using a low-pressure transfer molding machine (KTS-30, manufactured by Kotaki Seiki Co., Ltd.) under the conditions of a mold temperature of 175 ° C., an injection pressure of 6.9 MPa and a curing time of 120 seconds. The test resin composition was cast into a diameter of 100 mm and a thickness of 2 mm, and post-cured at 175 ° C. for 4 hours to prepare a test piece.
The volume resistivity was measured about the produced test piece. The measurement was performed by the MCC method. Specifically, the test piece is placed on the metal surface of the register table (Register table UFL, manufactured by Mitsubishi Chemical Analytech Co., Ltd.), and a resistivity meter (Hiresta-UX, manufactured by Mitsubishi Chemical Analytech Co., Ltd.) and a probe (Mitsubishi, Ltd.) The resistance was measured by applying an applied voltage of 1000 V using Chemical Analytech Co., Ltd., UR-100), and the volume resistivity was calculated from the resistance. The evaluation results are shown in Table 4 below. The unit is Ω · cm. The measured value was taken 30 seconds after the measurement start button was pressed. Moreover, the measurement of the volume resistivity was performed on temperature 20 degreeC, and the conditions of humidity 40% RH.

(Antistatic property)
The same test piece as the test piece used for evaluation of volume resistivity was fixed on a polytetrafluoroethylene sheet, and charge was removed by ionizer irradiation. Then, after rotating a rotating drum attached to four places of nitrile rubber around the circumference to make contact 16 times (4 rotations of the rotating drum) with a constant pressure load, the friction voltage on the surface of the test piece was measured. Evaluation criteria of the antistatic property were as follows based on the tribo voltage of Comparative Example 1. In addition, picking property improves, so that the friction electrical charging voltage of a molding is small.
◎: The frictional withstand voltage was less than 1/4 compared to Comparative Example 1.
○: The friction withstand voltage was at least 1/4 and less than 1/2 as compared with Comparative Example 1.
X: Frictional voltage was 1/2 or more as compared with Comparative Example 1.

As shown in Table 4, the moldings of the resin compositions of Examples 6 to 10, which respectively contain the functional fillers 1 to 5 which are the functional fillers of Examples 1 to 5, are compared with Comparative Examples 1 to 2, It was confirmed that the antistatic property is excellent.
Moreover, it was confirmed that the molded article of the resin composition of Examples 6 to 10 does not deteriorate the water absorption as compared with Comparative Example 3.
Moreover, compared with the comparative example 4, it was confirmed that the molded object of the resin composition of Examples 6-10 is low in volume resistivity, excellent in antistatic property, and further excellent in fluidity.
As mentioned above, when the molded object of the resin composition of Examples 6-10 which respectively contains the functional filler 1-5 which is a functional filler of Examples 1-5 is a resin composition as a molded object, it is water-absorbable It has been confirmed that the antistatic property and the antistatic property of the molded product can be further improved without deteriorating the

  Also, using the functional filler of Example 2, a granulated filler and a carbonized filler were produced. Details will be described below.

(Granulation filler)
First, a granulated filler was produced using the functional filler of Example 2.
Specifically, 250 g of the functional filler of Example 2, a mixed solvent of water and ethanol (water / ethanol weight ratio water / ethanol = 70/30) 875 g, and a water-soluble resol (manufactured by Sumitomo Bakelite Co., Ltd., PR 50 607 B) A mixture was made by mixing with 19.2 g. Next, the mixture was treated with a nitrogen gas closed circulation spray dryer (Sark Rex deep chill closed system CL-8i manufactured by Ohkawara Kakohki Co., Ltd.) using a disk spray system (rotation speed: 20000 rpm) and an inlet temperature of 140 ° C. The granulated filler according to Example 2 was obtained by spray-drying at an outlet temperature of about 90 ° C.

(Carburized filler)
Moreover, the carbonized filler was produced using the granulated filler which concerns on Example 2. FIG.
Specifically, the granulated filler according to Example 2 is heated from room temperature to 580 ° C. at a heating rate of 100 ° C./hour in a nitrogen atmosphere using a medium-sized batch furnace, and 1 at a temperature of 580 ° C. Heat treatment was carried out by holding for 5 hours to obtain carbides. Subsequently, the carbide and a plurality of alumina balls (diameter 10 mm) were put in a sieve with an opening of 45 μm, and the carbonized filler according to Example 2 was produced by sieving using a vibrating sieve.

(Observation of carbonized filler)
Subsequently, the structure of the carbonized filler according to Example 2 was observed. Specifically, the carbonized filler according to each example was observed using a scanning electron microscope (SEM). As an example of an observation result, the SEM photograph of the carbide filler concerning Example 2 is shown to FIGS. This confirms that the composite particles can be granulated and carbonized to control the phase structure.

  Moreover, the granulation filler and the carbonization filler were similarly produced and observed also about Example 1, 3-5. This confirms that the composite particles can be granulated and carbonized to control the phase structure.

Claims (21)

A functional filler that contains multiple composite particles,
The composite particles include a carbon material and core particles,
The functional filler, wherein the surface of the core particle is provided with a coating made of the carbon material. The functional filler according to claim 1, wherein
The functional filler, wherein the shape of the composite particle is spherical. It is the functional filler according to claim 1 or 2,
The functional filler, wherein the layer structure of the composite particle is a core-shell type structure in which the covering portion forms a shell layer and the core particle forms a core layer. It is a functional filler according to any one of claims 1 to 3,
The functional filler whose volume resistivity of the said core particle measured on the following measurement conditions 1 is 1 * 10 < ⁸ > ohm * cm or more and less than 1 * 10 < ¹⁵ > ohm * cm.
(Measurement condition 1)
The volume resistivity when a stress of 25.46 MPa is applied to the core particle is defined as the volume resistivity of the core particle. The functional filler according to any one of claims 1 to 4, wherein
The shape of the core particle is spherical, and
The functional filler, wherein the sphericity of the core particle is 0.8 or more. The functional filler according to any one of claims 1 to 5, wherein
The functional filler, wherein the core particle is at least one selected from the group consisting of inorganic oxides, inorganic nitrides, inorganic carbides, inorganic hydroxides and metals. The functional filler according to any one of claims 1 to 6, wherein the specific surface area of the core particle is 0.5 m ² / cm ³ or more and 30 m ² / cm ³ or less. The functional filler according to any one of claims 1 to 7, wherein
The carbon material contains amorphous carbon, and the functional filler (however, the carbon material excludes carbon black). The functional filler according to any one of claims 1 to 8, wherein
The functional filler whose sulfate ion concentration measured on the following measurement conditions 2 is 5.0 ppm or less about the said functional filler.
(Measurement condition 2)
-About the test solution of the said functional filler, the sulfate ion content in the said test solution is measured by the calibration curve method using a standard solution using an ion chromatography analyzer. The sulfate ion content of the functional filler used for the preparation of the test solution was taken as the sulfate ion concentration.
-The test solution of the functional filler was prepared by dispersing the functional filler in ultrapure water, heat-treating it at a temperature of 125 ° C for 20 hours using a thermostatic bath, and then removing the functional filler. The functional filler according to any one of claims 1 to 9,
The functional filler whose content of the nitrogen atom in the said carbon material is 0.1 wt% or more and 15 wt% or less with respect to all the atoms in the said carbon material. A functional filler according to any one of claims 1 to 10, wherein
The functional filler whose volume resistivity of the said functional filler measured on the following measurement conditions 3 is 1 * 10 < ⁵ > ohm * cm or more and less than 1 * 10 < ¹⁵ > ohm * cm.
(Measurement condition 3)
-The volume resistivity when applying a stress of 25.46 MPa to the functional filler is defined as the volume resistivity of the functional filler. It is the functional filler according to any one of claims 1 to 11,
The functional filler whose carbon coverage of the said functional filler measured on the following measurement conditions 4 is 0.5 wt%-30 wt%.
(Measurement condition 4)
-The weight reduction rate when the functional filler is heat treated in air at a temperature of 900 ° C. for 1 hour is taken as the carbon coverage.
The weight reduction rate is calculated by the following formula 1 when the mass of the functional filler before the heat treatment is A and the mass of the functional filler after the heat treatment is B.
(Formula 1) Weight reduction rate [wt%] = (A−B) / A × 100 The functional filler according to any one of claims 1 to 12,
The functional filler whose moisture absorption rate of the said functional filler measured on the following measurement conditions 5 is 7.0 wt% or less.
(Measurement condition 5)
-Conduct moisture absorption processing on the dried functional filler. Assuming that the mass of the functional filler before the moisture absorption treatment is X and the mass of the functional filler after the moisture absorption treatment is Y after the drying treatment, the moisture absorption rate is calculated by the following formula 2.
(Formula 2) Moisture absorption rate [wt%] = {(Y-X) / X} x 100
-The drying process is performed on the conditions which vacuum-dry the said functional filler for 12 hours at the temperature of 120 degreeC.
-The moisture absorption process is performed on the conditions hold | maintained the said functional filler dry-processed for one week in the high temperature and high humidity tank of temperature 40 degreeC and the fixed conditions of humidity 90% RH for 1 week.   A granulated filler obtained by granulating the functional filler according to any one of claims 1 to 13.   A carbonized filler obtained by carbonizing the granulated filler according to claim 14.   A resin composition comprising the functional filler according to any one of claims 1 to 13, the granulated filler according to claim 14, or the carbonized filler according to claim 15, and a resin.   A molded article obtained by molding the resin composition according to claim 16. A method for producing a functional filler according to any one of claims 1 to 13,
Mixing the organic resin and the core particles to form a mixture;
A carbonizing step of carbonizing the organic resin to obtain carbides by heat treatment;
A crushing step of crushing the carbide into composite particles;
A method of producing a functional filler, including: A method of producing a functional filler according to claim 18, which is
In the carbonizing step, the heat treatment includes a heat treatment at a maximum temperature of 500 ° C. or more and 700 ° C. or less. A method of producing a functional filler according to claim 18 or 19, wherein
The method for producing a functional filler, wherein the organic resin comprises an aniline resin. A method for producing a functional filler according to any one of claims 18 to 20, wherein
The method for producing a functional filler, wherein the organic resin is liquid at a temperature of 300 ° C.