JP2022154575A - Sealing resin composition - Google Patents

Abstract

To suppress the breakage of a tablet-shaped resin composition.SOLUTION: A tablet-shaped sealing resin composition contains a component (a): epoxy resin, a component (b): curing agent and a component (c): inorganic filler. The sealing resin composition has a flexural strength at 25°C of 2.20 MPa or more and 19.00 MPa or less as measured by the following method 1. The sealing resin composition also has a tablet density of 0.0005 g/mm3 or more and 0.005 g/mm3 or less.SELECTED DRAWING: None

Description

The present invention relates to an encapsulating resin composition.

As a technique related to the resin composition for sealing, there is one described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2019-135288). In the same document, there are disclosed a crystalline bisphenol A type epoxy resin and/or a bisphenol F type epoxy resin, a polyfunctional epoxy resin which is solid at 25° C. other than the above components, and two or more phenolic hydroxyl groups in one molecule. A thermosetting epoxy resin sheet for semiconductor encapsulation, which is obtained by molding a composition containing a phenolic compound, an inorganic filler, and a specific imidazole curing accelerator, into a sheet. In the same document, such a thermosetting epoxy resin sheet for semiconductor encapsulation has excellent flexibility and good handleability before curing, and has a high glass transition temperature after curing. , it is described that a thermosetting epoxy resin sheet for semiconductor encapsulation having excellent storage stability and moldability can be obtained.

JP-A-2019-135288

On the other hand, the present inventors have studied resin compositions molded into tablets. As a result, it became clear that there is room for improvement in terms of suppressing breakage of tablets.

According to the invention,
(a) an epoxy resin;
(b) a curing agent; and (c) an inorganic filler.
The bending strength of the sealing resin composition at 25° C. measured by the following method 1 is 2.20 MPa or more and 19.00 MPa or less,
A sealing resin composition is provided, wherein the tablet density of the sealing resin composition is 0.0005 g/mm ³ or more and 0.005 g/mm ³ or less.
(Method 1)
A three-point bending test of the sealing resin composition at 25° C. was performed in accordance with JIS K7171 under the conditions of a fulcrum distance of 20 mm, a speed of 10 mm/min, and a support base radius R2 of 2 mm. obtain.

Further, according to the present invention, for example, a cured product obtained by curing the sealing resin composition of the present invention can be obtained.

Further, according to the present invention, there is provided an electronic device obtained by encapsulating an electronic component or a semiconductor package with the encapsulating resin composition of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, the breakage of a tablet-shaped resin composition for sealing can be suppressed.

In this embodiment, the composition can contain each component alone or in combination of two or more.

(Resin composition for encapsulation)
In the present embodiment, the encapsulating resin composition (hereinafter also simply referred to as "resin composition") is in tablet form and contains the following components (a) to (c).
(a) Epoxy resin (b) Curing agent (c) Inorganic filler The bending strength of the encapsulating resin composition at 25°C, measured by Method 1 below, is 2.20 MPa or more and 19.00 MPa or less. The tablet density of the encapsulating resin composition is 0.0005 g/mm ³ or more and 0.005 g/mm ³ or less.
(Method 1)
A three-point bending test of the sealing resin composition at 25° C. is performed in accordance with JIS K7171 under the conditions of a fulcrum distance of 20 mm, a speed of 10 mm/min, and a support base radius R2 of 2 mm to obtain the bending strength.

In the present embodiment, the resin composition in tablet form contains components (a) to (c), and the bending strength and tablet density of the resin composition at 25° C. are within specific ranges. Therefore, breakage of the tablet can be effectively suppressed, and a resin composition having excellent storage stability can be obtained.

(Bending strength of resin composition)
The bending strength of the resin composition at 25° C. is 2.20 MPa or higher, preferably 3.00 MPa or higher, more preferably 4.00 MPa or higher, and still more preferably 10.00 MPa or higher, from the viewpoint of increasing tablet rigidity.
In addition, from the viewpoint of improving the impact resistance of the tablet, the bending strength at 25° C. of the resin composition is 19.00 MPa or less, preferably 16.00 MPa or less, more preferably 14.00 MPa or less, and still more preferably 12.00 MPa or less. 00 MPa or less.
The flexural strength of the resin composition is determined by method 1 described above.

(tablet density)
The tablet density of the encapsulating resin composition is 0.0005 g/mm ³ or more, preferably 0.0008 g/mm ³ or more, more preferably 0.001 g/mm ³ or more, from the viewpoint of increasing tablet rigidity. It is preferably 0.0015 g/mm ³ or more.
Further, from the viewpoint of improving the impact resistance of the tablet, the tablet density of the encapsulating resin composition is 0.005 g/mm ³ or less, preferably 0.004 g/mm ³ or less, more preferably 0.003 g/mm 3 or less. mm ³ or less, more preferably 0.0025 g/mm ³ or less.
The tablet density of the encapsulating resin composition is measured, for example, by dividing the tablet weight measured with an electronic balance by the tablet size measured with a vernier caliper.

The bending strength and tablet density of the resin composition are indices that reflect the degree of fragility of the tablet-shaped resin composition. The present inventors have found that by controlling the bending strength and tablet density of a tablet-shaped resin composition containing a combination of components (a) to (c) within the above ranges, it is possible to effectively suppress tablet breakage. I found it in

In the present embodiment, for example, by appropriately selecting the type and amount of each component contained in the resin composition, the preparation method of the resin composition, etc., it is possible to control the above bending strength and tablet density. be. Among these, for example, adjusting the size and amount of component (c), using resin density before tableting in an appropriate range, pressing time when tableting powder, etc. Adjusting the conditions of (1) to match the powder characteristics, adjusting the height of the resulting tablet, etc., are factors for setting the above bending strength and tablet density within the desired numerical ranges.

(breaking load)
The breaking load of the resin composition at 25° C. is, for example, 115 N or more, preferably 150 N or more, more preferably 200 N or more, and still more preferably 600 N or more, from the viewpoint of increasing tablet rigidity.
Moreover, from the viewpoint of improving the impact resistance of the tablet, the breaking load at 25° C. of the resin composition is, for example, 1000 N or less, preferably 900 N or less, more preferably 800 N or less, and still more preferably 700 N or less.
Here, the flexural modulus of the resin composition at 25° C. is measured by method 1 described above.

(tablet height)
The tablet height of the resin composition, that is, the maximum diameter in the direction perpendicular to the tablet diameter, is preferably 10 mm or more, more preferably 20 mm or more, and even more preferably 20 mm or more, from the viewpoint of improving productivity when melt-molding the tablet. is 25 mm or more.
In addition, from the viewpoint of preventing breakage such as breakage during transportation of the tablet, the height of the tablet of the resin composition is preferably 50 mm or less, more preferably 40 mm or less, and still more preferably 30 mm or less.

The form of the resin composition is tablet-like, and more specifically, it is obtained by tableting a powdery resin composition. Here, the term "granules" refers to either powder or granules.
Next, the constituent components of the resin composition will be described with specific examples.

(Component (a))
Component (a) is an epoxy resin.
Component (a) is, for example, biphenyl type epoxy resin; bisphenol type epoxy resin such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, tetramethylbisphenol F type epoxy resin; stilbene type epoxy resin; phenol novolac type epoxy resin; novolak type epoxy resins such as cresol novolac type epoxy resins; polyfunctional epoxy resins such as triphenylmethane type epoxy resins exemplified by triphenolmethane type epoxy resins and alkyl-modified triphenolmethane type epoxy resins; phenols having a phenylene skeleton Phenol aralkyl epoxy resins such as aralkyl epoxy resins, naphthol aralkyl epoxy resins having a phenylene skeleton, phenol aralkyl epoxy resins having a biphenylene skeleton, and naphthol aralkyl epoxy resins having a biphenylene skeleton; dihydroxynaphthalene epoxy resins, dihydroxynaphthalene naphthol-type epoxy resins such as epoxy resins obtained by glycidyl-etherifying the dimer of; triazine nucleus-containing epoxy resins such as triglycidyl isocyanurate and monoallyl diglycidyl isocyanurate; One or more selected from the group consisting of bridged cyclic hydrocarbon compound-modified phenol type epoxy resins and dihydroxyanthracene type epoxy resins.
From the viewpoint of making resin curability more preferable, component (a) is preferably a cresol novolac type epoxy resin, a bisphenol type epoxy resin, a dihydroxyanthracene type epoxy resin, a biphenyl type epoxy resin, a triphenylmethane type epoxy resin and a phenylene It contains one or more selected from the group consisting of phenol aralkyl epoxy resins having a skeleton.

From the viewpoint of improving moldability, the content of component (a) in the resin composition is preferably 1% by mass or more, more preferably 3% by mass or more, and still more preferably 5% by mass, relative to the entire resin composition. % or more.
Further, from the viewpoint of shrinkage suppression during molding, the content of component (a) in the resin composition is preferably 25% by mass or less, more preferably 20% by mass or less, and further preferably 20% by mass or less, relative to the entire resin composition. It is preferably 18% by mass or less, still more preferably 15% by mass or less, and even more preferably 10% by mass or less.

(Component (b))
Component (b) is a curing agent.
Examples of component (b) include linear aliphatic diamines having 2 to 20 carbon atoms such as ethylenediamine, trimethylenediamine, tetramethylenediamine, hexamethylenediamine, metaphenylenediamine, paraphenylenediamine, paraxylenediamine, 4, 4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodicyclohexane, bis(4-aminophenyl)phenylmethane , 1,5-diaminonaphthalene, metaxylenediamine, paraxylenediamine, 1,1-bis(4-aminophenyl)cyclohexane, aminos such as dicyanodiamide;
Resol-type phenolic resins such as aniline-modified resole resins and dimethyl ether resole resins; Novolac-type phenolic resins such as phenol novolac resins, cresol novolac resins, tert-butylphenol novolak resins, and nonylphenol novolak resins;
Polyfunctional phenol resins such as triphenolmethane-type phenol resins including trihydroxyphenylmethane-type phenol resins; Phenol aralkyl resins such as phenylene skeleton-containing phenol aralkyl resins and biphenylene skeleton-containing phenol aralkyl resins; Phenolic resins having a condensed polycyclic structure such as; Phenolic resins other than the above;
Polyoxystyrenes such as polyparaoxystyrene; alicyclic acid anhydrides such as hexahydrophthalic anhydride (HHPA) and methyltetrahydrophthalic anhydride (MTHPA), trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), acid anhydrides including aromatic acid anhydrides such as benzophenonetetracarboxylic acid (BTDA); polymercaptan compounds such as polysulfides, thioesters and thioethers; isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; and carboxylic acid-containing polyesters One or more selected from the group consisting of organic acids such as resins may be used.
Component (b) preferably contains a phenolic resin, more preferably at least one selected from the group consisting of phenolic novolac resins, triphenolmethane-type phenolic resins and biphenylene skeleton-containing phenolic aralkyl resins.

The content of component (b) in the resin composition is preferably 1% by mass or more, more preferably 2% by mass or more, and still more preferably 3% by mass, relative to the entire resin composition, from the viewpoint of improving curing properties. % or more, and more preferably 4 mass % or more.
In addition, from the viewpoint of improving fluidity and filling properties during molding, the content of component (b) in the resin composition is preferably 15% by mass or less, more preferably 12% by mass, based on the total resin composition. % by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less.

(Component (c))
Component (c) is an inorganic filler. Examples of component (c) include silica such as fused silica and crystalline silica; talc; titanium oxide; silicon nitride; and aluminum nitride.
From the viewpoint of excellent versatility, component (c) preferably contains silica, more preferably silica.
Examples of the shape of silica include spherical silica such as fused spherical silica, and crushed silica.
In addition, component (c) may contain a component capable of imparting flame retardancy. Specific examples of such components include one or more selected from the group consisting of aluminum hydroxide, magnesium hydroxide, antimony trioxide, zinc borate and zinc molybdate.

The average particle size _d50 of component (c) is preferably 3 μm or more, more preferably 5 μm or more, and still more preferably 10 μm or more, from the viewpoint of suppressing breakage of the doublet-shaped resin composition.
Also, from the viewpoint of improving the filling property during molding, the average particle size d50 of component (c) is preferably 30 μm or less, more preferably 25 μm or less, and even more preferably ₂₀ μm or less.

Here, the average particle diameter d ₅₀ of component (c) is the average particle diameter (volume average diameter) measured with a commercially available laser particle size distribution meter (eg, SALD-7000 manufactured by Shimadzu Corporation).

The content of component (c) in the resin composition is preferably 70% by mass or more, more preferably 75% by mass, based on the entire resin composition, from the viewpoint of suppressing breakage of the doublet-shaped resin composition. % by mass or more, more preferably 80% by mass or more, and even more preferably 85% by mass or more.
In addition, from the viewpoint of improving fluidity and filling properties during molding, the content of component (c) in the resin composition is preferably 90% by mass or less, more preferably 88% by mass, based on the entire resin composition. % or less, more preferably 86 mass % or less.

The content of component (c) in the resin composition is preferably 55% by volume or more, more preferably 60% by volume, based on the entire resin composition, from the viewpoint of suppressing breakage of the doublet-shaped resin composition. % by volume or more, more preferably 65% by volume or more.
In addition, from the viewpoint of improving fluidity and filling properties during molding, the content of component (c) in the resin composition is, for example, 85% by volume, preferably 80% by volume or less, relative to the entire resin composition. Yes, more preferably 78% by volume or less, still more preferably 75% by volume or less.

The resin composition may contain components other than components (a) to (c). For example, the resin composition may further contain one or more selected from the group consisting of curing accelerators, ion catchers, coupling agents, low stress materials, release agents, colorants and other additives. good.

(Curing accelerator)
As the curing accelerator, for example, one that accelerates the cross-linking reaction between the component (a) epoxy resin and the component (b) curing agent can be used. Examples of curing accelerators include phosphorus atom-containing compounds such as organic phosphines, tetrasubstituted phosphonium compounds, phosphobetaine compounds, adducts of phosphine compounds and quinone compounds, adducts of phosphonium compounds and silane compounds; 1,8-diazabicyclo [5.4.0] One type selected from amidines, tertiary amines exemplified by undecene-7, benzyldimethylamine, 2-methylimidazole and the like, nitrogen atom-containing compounds such as quaternary salts of the above amidines and amines Or two or more types can be included.

From the viewpoint of improving curability, the content of the curing accelerator in the resin composition is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, relative to the entire resin composition. be.
In addition, from the viewpoint of improving the production stability of the cured product, the content of the curing accelerator in the resin composition is preferably 1% by mass or less, more preferably 0.8% by mass, relative to the entire resin composition. % or less, more preferably 0.6 mass % or less.

(coupling agent)
Coupling agents include, for example, epoxysilane, mercaptosilane, aminosilanes such as phenylaminosilane, alkylsilanes, ureidosilanes, vinylsilanes, various silane compounds such as methacrylsilane; titanium compounds; aluminum chelates; aluminum/zirconium compounds, etc. can contain one or more selected from known coupling agents.
From the viewpoint of improving the strength and toughness of the cured product in a well-balanced manner, the coupling agent is preferably a silane coupling agent, more preferably a silane coupling agent having an amino group.

From the viewpoint of improving curability, the content of the coupling agent in the resin composition is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, based on the total resin composition. More preferably, it is 0.2% by mass or more.
In addition, from the viewpoint of improving the production stability of the cured product, the content of the coupling agent in the resin composition is preferably 2% by mass or less, more preferably 1% by mass or less, relative to the entire resin composition. , more preferably 0.7% by mass or less.

(Low stress material)
The low-stress material includes, for example, one or more selected from the group consisting of silicone oil, silicone rubber and carboxyl group-terminated butadiene acrylonitrile rubber.

(Release agent)
Release agents include, for example, natural waxes such as carnauba wax; oxidized polyethylene wax, montan acid ester wax, reaction products of polycondensates of 1-alkene (C>10) and maleic anhydride and stearyl alcohol, and the like. Synthetic waxes; higher fatty acids such as zinc stearate and metal salts thereof; and one or more selected from paraffin.
The content of the release agent in the resin composition is preferably 0.05% by mass or more, more preferably 0.05% by mass or more, more preferably It is 0.1% by mass or more, preferably 5% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less.

(coloring agent)
Colorants include, for example, one or more selected from the group consisting of carbon black, black titanium oxide, red iron oxide, organic pigments, and the like.
The content of the colorant in the resin composition is preferably 0.05% by mass or more, more preferably 0.1%, relative to the entire resin composition, from the viewpoint of making the appearance of the cured product more preferable. % by mass or more, preferably 1% by mass or less, and more preferably 0.5% by mass or less.

Other additives include, for example, antioxidants.

In the present specification, the density of the melt-cured product of the powdery resin composition before tableting is also referred to as "resin density" as appropriate.
In the present embodiment, the resin density is preferably 0.0005 g/mm ³ or more, more preferably 0.0008 g/mm ³ or more, still more preferably 0.001 g/mm ³ or more, from the viewpoint of improving resin strength. Even more preferably, it is 0.0015 g/mm ³ or more.
From the viewpoint of improving resin fluidity, the resin density of the resin composition is preferably 0.005 g/mm ³ or less, more preferably 0.004 g/mm ³ or less, and even more preferably 0.003 g/mm ³ . 0.0025 g/mm 3 or less, and more preferably 0.0025 g/mm ³ or less.
As the resin density, a value obtained by multiplying the specific gravity (25° C.) of a test piece obtained by a method conforming to JIS K 6911 by 1×10 ⁻³ is used as the resin density. A method for preparing a test piece will be described later in the section of Examples.

Next, a method for producing a resin composition will be described.
In the present embodiment, the resin composition can be obtained, for example, by mixing each of the above-described components by known means, further melt-kneading with a kneader such as a roll, kneader or extruder, and cooling and pulverizing. can be done. In addition, the degree of dispersion, fluidity, etc. of the obtained resin composition may be appropriately adjusted.

Here, in the present embodiment, in order to obtain a resin composition that satisfies the above-described conditions of bending strength, it is important to devise a production method that differs from the conventional technique. For example, in producing the resin composition, it is preferable to adjust the size and amount of the component (c) and adjust the mixing conditions such as the mixing speed of the raw materials to adjust the properties of the granules of the resin composition. In addition, it is also preferable to use one having a resin density, etc. within an appropriate range before tableting. In addition, it is preferable to adjust conditions such as pressurization time in tableting the granular material in accordance with powder properties, and to adjust the height of the resulting tablet. This makes it possible to more stably control the bending strength and tablet density of the resulting tablet within the ranges described above.

By curing the resin composition obtained in this embodiment, a cured product of the resin composition can be obtained.
Moreover, the resin composition in the present embodiment can be suitably used, for example, as a sealing material for electronic components or semiconductor packages.

Although the embodiments of the present invention have been described above with reference to the drawings, these are examples of the present invention, and various configurations other than those described above can also be adopted.

EXAMPLES The present embodiment will be specifically described below with reference to examples and comparative examples, but the present embodiment is not limited to these examples.

(Prescription Examples 1-5)
For each example, each component shown in Table 1 was mixed with a mixer at room temperature for 5 minutes. Next, the obtained mixture was roll-kneaded under conditions of a high-temperature roll surface temperature of 90° C. and a low-temperature roll surface temperature of 25° C., cooled and pulverized to obtain a resin composition in the form of powder.

Details of each component in Table 1 are as follows.
(Epoxy resin)
Epoxy resin 1: ortho-cresol novolac (OCN) type epoxy resin, EXP-S, epoxy resin manufactured by DIC Corporation 2: OCN type epoxy resin, YDCN-800-65, epoxy resin manufactured by Nippon Steel Chemical Co., Ltd. 3: OCN type epoxy resin , YDCN-800-70, Nippon Steel Chemical Co., Ltd. epoxy resin 4: dihydroxyanthracene type epoxy resin, YX8800, Mitsubishi Chemical Co. epoxy resin 5: bisphenol A type epoxy resin, YL6810, Mitsubishi Chemical Co. epoxy resin 6: biphenyl type epoxy resin, NC3000, Nippon Kayaku Co., Ltd. epoxy resin 7: a mixture of triphenylmethane type epoxy resin and biphenyl type epoxy resin, EPIKOTE YL6677, Mitsubishi Chemical Corporation epoxy resin 8: phenol aralkyl type epoxy resin having a phenylene skeleton, NC-2000, epoxy resin 9 manufactured by Nippon Kayaku Co., Ltd.: Biphenyl type epoxy resin, Epicoat YX4000K, manufactured by Mitsubishi Chemical Co., Ltd.

(curing agent)
Curing agent 1: Triphenol methane type phenolic resin, MEH-7500, Meiwa Kasei Co., Ltd. Curing agent 2: Phenol novolac resin, Sumilite Resin PR-51470, Sumitomo Bakelite Co., Ltd. Curing agent 3: Phenol novolac resin, Sumilite Resin PR-51714 , Sumitomo Bakelite Curing Agent 4: α-naphthol skeleton-containing phenol aralkyl resin, SN-485, Nippon Steel Chemical & Materials Curing Agent 5: Phenol Novolac Resin, Sumilite Resin PR-HF-3, Sumitomo Bakelite Curing Agent 6: Biphenylene skeleton-containing phenol aralkyl resin, GPH-65, manufactured by Nippon Kayaku Co., Ltd. Curing agent 7: Trisphenylmethane type phenol resin, HE910-20, manufactured by Air Water

(Curing accelerator)
Curing accelerator 1: Triphenylphosphine, PP-360, manufactured by K.I Kasei Co., Ltd. Curing accelerator 2: Curing accelerator represented by the following formula

(Method for producing curing accelerator 2)
249.5 g of phenyltrimethoxysilane and 384.0 g of 2,3-dihydroxynaphthalene were added and dissolved in a flask containing 1800 g of methanol, and then 231.5 g of a 28% sodium methoxide-methanol solution was added dropwise with stirring at room temperature. Further, a solution prepared by dissolving 503.0 g of tetraphenylphosphonium bromide in 600 g of methanol was added dropwise thereto under stirring at room temperature to precipitate crystals. The precipitated crystals were filtered, washed with water, and dried in a vacuum to obtain a hardening accelerator 2 of peach-white crystals.

Curing accelerator 3: 4-hydroxy-2-(triphenylphosphonium) phenolate, TPP-BQ, manufactured by K.I. Kasei Co., Ltd.

(Inorganic filler)
Inorganic filler 1: fused crushed silica, FMT-05, manufactured by Fumitech, average particle size 4.7 μm
Inorganic filler 2: silica, SC-2500-SQ, manufactured by Admatechs, average particle size 0.5 μm
Inorganic filler 3: aluminum hydroxide, CL-303, manufactured by Sumitomo Chemical Co., Ltd., average particle size 4.0 μm
Inorganic filler 4: crushed silica, FS-784, manufactured by Denka, average particle size 13.0 μm
Inorganic filler 5: Fused spherical silica, S-CO, manufactured by Nippon Steel Chemical & Materials, average particle size 20 μm
Inorganic filler 6: Spherical silica, FEB24S5, manufactured by Admatechs, average particle size 12.3 μm
Inorganic filler 7: silica, TS-6026, manufactured by Nippon Steel Chemical & Materials, average particle size 9 μm
Inorganic filler 8: silica, FB-105, manufactured by Denka, average particle size 11.7 μm
Inorganic filler 9: silica, ES-355, manufactured by Tokai Mineral Co., Ltd., average particle size 29.4 μm

(coupling agent)
Coupling agent 1: N-phenyl-3-aminopropyltrimethoxysilane, CF4083, manufactured by Dow Corning Toray Co., Ltd. Coupling agent 2: γ-glycidoxypropyltrimethoxysilane, GPS-M, manufactured by JNC

(Low stress material)
Low-stress material 1: Silicone elastomer, CF-2152, manufactured by Dow Corning Toray Co., Ltd. Low-stress material 2: Epoxidized polybutadiene, JP-200, manufactured by Nippon Soda Co., Ltd. Low-stress material 3: Acrylonitrile butadiene rubber, CTBN 1008-SP, Ube Made by Kosan Co., Ltd. (Carboxyl group-terminated butadiene acrylic rubber)

(Release agent)
Release agent 1: carnauba wax, C-WAX, manufactured by Toa Kasei Co., Ltd. (colorant)
Coloring agent 1: carbon black, #5, manufactured by Mitsubishi Chemical Corporation

(Examples 1 to 11, Comparative Examples 1 to 5)
A resin composition in the form of tablets was obtained by tableting the resin composition in the form of granules of any one of Formulation Examples 1 to 5. Tables 2 to 6 show the formulation of the powdery resin composition used in each example, the preparation conditions of the tablets, and the measurement results of the obtained tablets.

(Method for producing tablet-shaped resin composition)
Using a tablet machine (BARPRESS manufactured by Kikusui Seisakusho Co., Ltd.), the resin composition in powder form is compressed and tableted under the production conditions shown in Tables 2 to 6, and a tablet having a weight of 8 g and a diameter of 14 mm is obtained. A resin composition was obtained.
In Tables 2 to 6, "resin density" is the density of the melt-cured product of the powdery resin composition in each formulation example, and was measured by the following method.
"Pressure time" refers to the time during which the tip of the punch of the tableting machine is at the height of the tablet from the lower end of the die.
"Tablet density" is the density of the tablet-shaped resin composition obtained in each example, and was measured by the following method.
The “tablet height” was defined as the longest diameter of the tablet-shaped resin composition obtained in each example, that is, the maximum diameter in the direction perpendicular to the tablet diameter.

(Measurement method of tablet density)
The tablet weight of the resin composition obtained in each example was weighed with an electronic balance. Moreover, the tablet size of the resin composition obtained in each example was measured with a vernier caliper.
The obtained tablet weight was divided by the tablet size to obtain the tablet density [g/mm ³ ].

(Method for measuring resin density)
Using a low-pressure transfer molding machine (KTS-30, manufactured by Kotaki Seiki Co., Ltd.), the resin composition of each powder was injection molded under the conditions of a mold temperature of 175 ° C., an injection pressure of 8.3 MPa, and a curing time of 2 minutes. , a disc-shaped molded article having a diameter of 50 mm and a thickness of 3 mm was obtained. Next, the obtained molded article was post-cured at 175° C. for 4 hours to obtain a test piece composed of a cured product of each resin composition. Next, the specific gravity (25°C) of the test piece obtained by a method conforming to JIS K 6911 was measured, and the value multiplied by 1 x 10 ^-3 was used as the resin density. The unit of resin density is g/mm ³ .

(How to measure tablet height)
The height of the tablet was measured by using a caliper to measure the maximum diameter in the direction perpendicular to the diameter of the tablet.

(bending strength)
The bending strength of the tablet-shaped resin composition obtained in each example was measured according to Method 1 described above.

(breaking load)
According to Method 1 described above, the breaking load (N) at 25° C. of the tablet-shaped resin composition obtained in each example was measured.

(bent)
40 tablets were placed in a V-type mixer (Tokuju Kosakusho, V-10) and mixed for 10 minutes. Among the tablets after the completion of mixing, those with a loss of 10% or more of the volume were counted as "broken".

From Tables 2 to 6, in the tablet-shaped resin compositions obtained in each example, tablet breakage due to folding was favorably suppressed.

Claims (6)

(a) an epoxy resin;
(b) a curing agent; and (c) an inorganic filler.
The bending strength of the sealing resin composition at 25° C. measured by the following method 1 is 2.20 MPa or more and 19.00 MPa or less,
A resin composition for sealing, wherein the tablet density of the resin composition for sealing is 0.0005 g/mm ³ or more and 0.005 g/mm ³ or less.
(Method 1)
A three-point bending test of the sealing resin composition at 25° C. was performed in accordance with JIS K7171 under the conditions of a fulcrum distance of 20 mm, a speed of 10 mm/min, and a support base radius R2 of 2 mm. obtain. 2. The encapsulating resin composition according to claim 1, wherein the encapsulating resin composition has a breaking load at 25[deg.] C. of 115 N or more and 1000 N or less, as measured by Method 1. The component (a) is selected from the group consisting of cresol novolak-type epoxy resins, bisphenol-type epoxy resins, dihydroxyanthracene-type epoxy resins, biphenyl-type epoxy resins, triphenylmethane-type epoxy resins, and phenol aralkyl-type epoxy resins having a phenylene skeleton. The encapsulating resin composition according to claim 1 or 2, comprising one or more of 4. Any one of claims 1 to 3, wherein the content of the component (c) in the encapsulating resin composition is 70% by mass or more and 90% by mass or less relative to the entire encapsulating resin composition. The encapsulating resin composition according to 1. 5. Any one of claims 1 to 4, wherein the content of the component (c) in the encapsulating resin composition is 55% by volume or more and 80% by volume or less with respect to the entire encapsulating resin composition. The encapsulating resin composition according to 1. The encapsulating resin composition according to any one of claims 1 to 5, wherein the component (c) has an average particle size _d50 of 3 µm or more and 30 µm or less.