Tablet-shaped epoxy resin molding material, columnar tablet, and method for producing columnar tablet

Abstract

A tablet-shaped epoxy resin molding material according to the present invention contains an epoxy resin and a fibrous or acicular filler. The cross-sectional area is 3 cm2 to 100 cm2. The compression ratio calculated from [(M / G) / V]×100, where G is the specific gravity, M (g) is the mass, and V (cm3) is the volume, as measured in accordance with JIS 6911:2006, in the tablet-shaped epoxy resin molding material, satisfies 70-95%.

Description

Tablet-shaped epoxy resin molding material, columnar tablets, and method for manufacturing columnar tablets

[0001] The present invention relates to a tablet-shaped epoxy resin molding material, a pillar-shaped tablet, and a method for producing the pillar-shaped tablet.

[0002] Various methods for molding tablet-shaped epoxy resin molding materials have been developed. One such technique is known from Patent Document 1. Patent Document 1 describes a transfer molding method for encapsulating semiconductor elements using a tablet-shaped epoxy resin composition containing an inorganic filler such as quartz glass powder, talc, silica powder, alumina powder, or calcium carbonate (see, for example, claim 1 and paragraphs 0005 and 0030 of Patent Document 1).

[0003] Japanese Patent Application Publication No. 9-208805

[0004] However, as a result of investigations by the present inventors, it has been found that there is room for improvement in the tablet-shaped epoxy resin molding material described in Patent Document 1 above in terms of breakage resistance during transportation and fracture toughness.

[0005] As a result of further investigation, the present inventors have found that by lowering the compression ratio of tablet-shaped epoxy resin molding material to an appropriate value, it is possible to form molded articles that are excellent in resistance to breakage during transportation and in fracture toughness, and have thereby completed the present invention.

[0006] According to one aspect of the present invention, there are provided the following tablet-shaped epoxy resin molding material, pillar-shaped tablets, and method for producing pillar-shaped tablets.

[0007] 1. A tablet-shaped epoxy resin molding material containing an epoxy resin and a fibrous or needle-like filler, and having a cross-sectional area of ​​3 cm ２ More than 100cm ２ The specific gravity of the tablet-shaped epoxy resin molding material measured in accordance with JIS 6911:2006 is G, the mass is M (g), and the volume is V (cm ３2. A tablet-shaped epoxy resin molding material having a compressibility calculated from [(M / G) / V] x 100 of 70% or more and 95% or less. 2. A tablet-shaped epoxy resin molding material according to 1., wherein the volume-average fiber length of the fibrous or needle-like filler, measured by the following procedure A, is 5 μm or more and 500 μm or less. (Procedure A) The tablet-shaped epoxy resin molding material is dissolved in acetone to remove the resin component, and then the insoluble matter is dispersed on a glass plate. An image of the filler in the insoluble matter is taken using an optical microscope, and the fiber length is measured using an image analyzer. The volume-average fiber length is the average fiber length based on the fiber volume of the 100 longest fiber pieces of the filler. 3. 1. or 2. 1. A tablet-shaped epoxy resin molding material according to claim 1, wherein L / D is 3 or more and 100 or less, where L is the volume-average fiber length of the fibrous or needle-like filler measured by the following procedure A and D is the number-average fiber diameter of the fibrous or needle-like filler measured by the following procedure B. (Procedure A) The tablet-shaped epoxy resin molding material is dissolved in acetone to remove the resin component, and then the insoluble matter is dispersed on a glass plate. An image of the filler in the insoluble matter is taken using an optical microscope, and the fiber length is measured using an image analyzer. The volume-average fiber length is defined as the average fiber length based on the fiber volume of the 100 longest fiber pieces. (Procedure B) A scanning electron microscope is used to measure 100 cross sections of the fibrous filler in a cross section of the tablet-shaped epoxy resin molding material, and the average of the smallest diameters of each fiber cross section is determined as the number-average fiber diameter. 1. A tablet-shaped epoxy resin molding material according to any one of claims 1 to 9, wherein the fibrous or needle-like filler comprises one or more selected from the group consisting of wollastonite fiber, glass fiber, metal fiber, carbon fiber, fibrous aluminum oxide, aramid fiber, silicon carbide whisker, silicon nitride whisker, and potassium titanate whisker.5. The tablet-shaped epoxy resin molding material according to any one of 1. to 4., wherein the spiral flow measured according to the following procedure is 20 cm or more. (Procedure) Using a low-pressure transfer molding machine, the tablet-shaped epoxy resin molding material is injected into a spiral flow measurement mold in accordance with EMMI-1-66 under conditions of a mold temperature of 175°C, an injection pressure of 6.9 MPa, and a curing time of 120 seconds, and the flow length (cm) is measured. 6. The tablet-shaped epoxy resin molding material according to any one of 1. to 5., wherein the content of the fibrous or needle-like filler is 5% by mass or more and 80% by mass or less, relative to 100% by mass of the tablet-shaped epoxy resin molding material. 7. The tablet-shaped epoxy resin molding material according to any one of 1. to 6., wherein the epoxy resin contains a cresol novolac epoxy resin and / or a bisphenol A epoxy resin. 8. 1. to 7. 9. The tablet-shaped epoxy resin molding material according to any one of 1. to 8., which contains one or more curing catalysts selected from the group consisting of amine-based catalysts and phosphorus-based catalysts. 9. The tablet-shaped epoxy resin molding material according to any one of 1. to 8., which has a diameter of 5 cm. ３ More than 1500cm ３ 10. A tablet-shaped epoxy resin molding material having a volume of 3 cm or less. 10. A tablet-shaped epoxy resin molding material according to any one of 1. to 9., which is used for either magnet fixing, electronic control unit sealing, coil sealing, or stator core sealing. 11. A pillar-shaped tablet molded from the tablet-shaped epoxy resin molding material according to any one of 1. to 10.. 12. A method for producing an epoxy resin molding material, comprising the steps of: melt-kneading an epoxy resin composition containing an epoxy resin and a fibrous or needle-like filler to obtain an epoxy resin molding material; and using the obtained epoxy resin molding material to obtain a pillar-shaped tablet, wherein the cross-sectional area of ​​the pillar-shaped tablet is 3 cm or less. ２ More than 100cm ２The specific gravity of the columnar tablet measured in accordance with JIS 6911:2006 is G, the mass is M (g), and the volume is V (cm ３ ) and the compression rate calculated from [(M / G) / V]×100 is 70% or more and 95% or less.

[0008] According to the present invention, there are provided a tablet-shaped epoxy resin molding material, a columnar tablet, and a method for producing the columnar tablet, which can be used to mold a molded article that is excellent in resistance to breakage during transportation and in fracture toughness.

[0009] FIG. 1 is a cross-sectional view illustrating an outline of a tension and compression testing machine.

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are designated by similar reference numerals, and descriptions thereof will be omitted where appropriate. Furthermore, the drawings are schematic diagrams and do not correspond to actual dimensional proportions.

[0011] An outline of the tablet-shaped epoxy resin molding material of this embodiment will be described.

[0012] The tablet-shaped epoxy resin molding material of this embodiment contains an epoxy resin and a fibrous or needle-like filler, and has a cross-sectional area of ​​3 cm ２ More than 100cm ２ The specific gravity measured in accordance with JIS 6911:2006 is G, the mass is M (g), and the volume is V (cm ３ ), the compression ratio calculated from [(M / G) / V]×100 is configured to be 70% or more and 95% or less.

[0013] According to the findings of the present inventors, it has been found that by appropriately lowering the compression ratio of tablet-shaped epoxy resin molding material, it is possible to form molded articles with excellent fracture toughness. Although the detailed mechanism is unclear, it is presumed that an appropriately low tablet compression ratio means that the tablet is formed under mild conditions, and that this can prevent the fiber length of the fibrous or needle-like filler from shortening during the tablet molding process under mild conditions, thereby preventing a decrease in the fracture toughness of the molded article.

[0014] The upper limit of the compression ratio is 95% or less, preferably 94% or less, more preferably 93% or less. This allows a molded article with excellent fracture toughness to be molded. Furthermore, mechanical strength such as flexural modulus can be improved. On the other hand, the lower limit of the compression ratio is, for example, 70% or more, preferably 75% or more, more preferably 80% or more. This allows the molded article to be less susceptible to breakage during transportation. Transportation can be by air, land, or sea.

[0015] In this embodiment, the compression ratio can be controlled by appropriately selecting, for example, the types and amounts of each component contained in the epoxy resin molding material, the method for preparing the epoxy resin molding material, etc. Among these, factors for setting the compression ratio within a desired range include, for example, appropriately controlling the molding pressure and compression time during molding as production conditions, and increasing the fiber length of the fiber filler.

[0016] Such epoxy resin molding materials can be used for magnet fixing, electronic control unit (ECU) sealing, coil sealing, stator core sealing, etc. Specifically, tablet-shaped epoxy resin molding materials can be used for magnet fixing, electronic control unit (ECU) sealing, coil sealing, or stator core sealing using known molding methods. In each of these applications, the mechanical properties of the molded product, such as the flexural modulus, can be improved. Furthermore, in rotor cores with skew structures, the occurrence of gaps when filled with magnet fixing materials can be suppressed.

[0017] The columnar tablet of this embodiment is a columnar molded body obtained by molding the above-mentioned epoxy resin molding material.

[0018] A method for producing a tablet-shaped epoxy resin molding material may include, for example, an extrusion molding method, a step of melt-kneading an epoxy resin composition containing at least an epoxy resin and a fibrous or needle-like filler to obtain an epoxy resin molding material, and a step of using the obtained epoxy resin molding material to obtain tablets.

[0019] The tablets can be obtained by any known method, for example, by tableting a granular epoxy resin composition into tablets using a tablet molding machine. However, the method is not limited to this, and a method of cutting a molten epoxy resin molding material while continuously extruding it from an opening at the tip of an extruder to obtain tablets can also be used.

[0020] The particulate epoxy resin composition contains powder and / or granules. For example, relatively coarse particles (granules) are crushed and / or classified to obtain relatively fine particles (powder). The particle shape of the epoxy resin composition is not particularly limited, and may be spherical, polygonal, irregular, or the like. These may be used alone or in combination of two or more.

[0021] The volume of the tablet-shaped epoxy resin molding material (tablet) is, for example, 5 cm ３ More than 1500cm ３ Less than 10 cm, preferably ３ More than 1000cm ３ The cross-sectional area of ​​the pillar-shaped tablet is, for example, 3 cm ２ More than 100cm ２ Less than 10 cm, preferably ２ Over 95cm ２ The length of the pillar-shaped tablet is, for example, 10 mm or more and 300 mm or less, and preferably 20 mm or more and 200 mm or less.

[0022] By using a tablet-shaped epoxy resin molding material and a known molding method such as transfer molding, it is possible to manufacture any fixing structure or sealing structure selected from the group consisting of a magnet fixing structure, an electronic control unit sealing structure, a coil sealing structure, and a stator core sealing structure, as exemplified below.

[0023] Regarding the above-mentioned fixed structure or sealing structure, for example, International Publication WO2012 / 029278 etc. is useful as a rotor core to which a magnet is fixed, International Publication WO2016 / 139985 etc. is useful as an in-vehicle electronic control unit, and Japanese Patent Application Laid-Open No. 2020-094092 etc. is useful as a stator core.

[0024] The following describes a case where an epoxy resin molding material is used for the magnet fixing structure. The rotor core has a plurality of holes and a permanent magnet inserted into each of the holes. The permanent magnet can be fixed to the rotor core by filling the gaps between the holes and the permanent magnets with epoxy resin molding material.

[0025] The use of an epoxy resin molding material in a sealing structure for an automotive electronic control unit will be described. The automotive electronic control unit includes a substrate on which electronic components and the like are mounted. In the automotive electronic control unit, at least a portion of the substrate together with the electronic components can be encapsulated with the epoxy resin molding material.

[0026] This section explains the use of epoxy resin molding material in a coil sealing structure. Coils have windings such as copper wire and are used in motors and transformers. These coils are molded (sealed) with epoxy resin molding material to provide insulation.

[0027] A case where an epoxy resin molding material is used in a stator core sealing structure will be described. The stator core includes multiple teeth and coils (windings) wound around each of the multiple teeth. The coils wound around the teeth are sealed with epoxy resin molding material, thereby insulating the coils from the stator core. Furthermore, if the teeth formed in the stator core have housings, the coils wound around the teeth can be housed in the housings and the spaces between them can be filled with epoxy resin molding material, thereby insulating the coils from the stator core. As a manufacturing example, an insulating layer is formed on the surface of the stator core using epoxy resin molding material. Then, a coil is inserted into the teeth and sealed with epoxy resin molding material. The windings used in the coils and stator core may be round or rectangular wire.

[0028] The step of manufacturing the fixed structure or the sealing structure may be carried out, for example, using a tablet-shaped epoxy resin molding material at a temperature of 120°C or higher and 200°C or lower and a pressure of 3 MPa or higher and 15 MPa or lower, preferably at a temperature of 140°C to 180°C and a pressure of 5 to 12 MPa.

[0029] The lower limit of the spiral flow of an epoxy resin molding material is, for example, 30 cm or more, preferably 50 cm or more. On the other hand, the upper limit of the spiral flow of an epoxy resin molding material is, for example, 250 cm or less, preferably 200 cm or less. The spiral flow can be measured according to the following procedure. Using a low-pressure transfer molding machine, the epoxy resin molding material is injected into a spiral flow measurement mold conforming to EMMI-1-66 under conditions of a mold temperature of 175°C, an injection pressure of 6.9 MPa, and a curing time of 120 seconds, and the flow length (cm) is measured.

[0030] The method for producing tablets using the epoxy resin molding material of this embodiment is not limited to compression molding, and extrusion molding, transfer molding, injection molding, etc. may also be used.

[0031] Each component of the epoxy resin molding material of this embodiment will be described in detail below.

[0032] [Epoxy Resin] The epoxy resin molding material contains an epoxy resin. Examples of the epoxy resin include novolac-type phenolic resins such as phenol novolac resin, cresol novolac resin, and bisphenol A novolac resin, and resol-type phenolic resin, novolac-type epoxy resins such as phenol novolac-type epoxy resin and cresol novolac-type epoxy resin, bisphenol-type epoxy resins such as bisphenol A-type epoxy resin and bisphenol F-type epoxy resin, aromatic glycidylamine-type epoxy resins such as N,N-diglycidylaniline, N,N-diglycidyltoluidine, diaminodiphenylmethane-type glycidylamine, and aminophenol-type glycidylamine, hydroquinone-type epoxy resin, biphenyl-type epoxy resin, and stilbene. Examples of epoxy resins include aralkyl-type epoxy resins such as aryl aryl epoxy resins, triphenolmethane-type epoxy resins, triphenolpropane-type epoxy resins, alkyl-modified triphenolmethane-type epoxy resins, triazine nucleus-containing epoxy resins, dicyclopentadiene-modified phenol-type epoxy resins, naphthol-type epoxy resins, naphthalene-type epoxy resins, phenol aralkyl-type epoxy resins having a phenylene and / or biphenylene skeleton, and naphthol aralkyl-type epoxy resins having a phenylene and / or biphenylene skeleton; and aliphatic epoxy resins such as vinylcyclohexene dioxide, dicyclopentadiene oxide, and alicyclic diepoxy adipides. These may be used alone or in combination of two or more. Among these, the epoxy resin preferably includes a cresol novolac-type epoxy resin and / or a bisphenol A-type epoxy resin.

[0033] The content of the epoxy resin is preferably 5% by mass or more and 40% by mass or less, more preferably 10% by mass or more and 20% by mass or less, based on the total amount of the epoxy resin molding material.

[0034] [Curing Agent] The epoxy resin molding material may contain a curing agent that cures the epoxy resin. A preferred curing agent is, for example, a phenolic resin-based curing agent. Examples of phenolic resin-based curing agents include novolac-type resins such as phenol novolac resin, cresol novolac resin, and naphthol novolac resin; multifunctional phenolic resins such as triphenolmethane-type phenolic resin; modified phenolic resins such as terpene-modified phenolic resin and dicyclopentadiene-modified phenolic resin; aralkyl-type resins such as phenol aralkyl resins having a phenylene and / or biphenylene skeleton and naphthol aralkyl resins having a phenylene and / or biphenylene skeleton; and bisphenol compounds such as bisphenol A and bisphenol F. These may be used alone or in combination of two or more. Such phenolic resin-based curing agents provide a good balance of flame resistance, moisture resistance, electrical properties, curability, storage stability, and the like.

[0035] Further, examples of curing agents that can be used in combination include polyaddition type curing agents and condensation type curing agents.

[0036] Examples of polyaddition curing agents include aliphatic polyamines such as diethylenetriamine (DETA), triethylenetetramine (TETA), and metaxylenediamine (MXDA), aromatic polyamines such as diaminodiphenylmethane (DDM), m-phenylenediamine (MPDA), and diaminodiphenylsulfone (DDS), as well as polyamine compounds including dicyandiamide (DICY) and organic acid dihydrazides; alicyclic acid anhydrides such as hexahydrophthalic anhydride (HHPA), methyltetrahydrophthalic anhydride (MTHPA), and aromatic acid anhydrides such as trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), and benzophenonetetracarboxylic acid (BTDA); polyphenol compounds such as novolac phenolic resins and phenol polymers; polymercaptan compounds such as polysulfides, thioesters, and thioethers; isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; and organic acids such as carboxylic acid-containing polyester resins.

[0037] Examples of condensation type curing agents include resol resins, urea resins such as methylol group-containing urea resins, and melamine resins such as methylol group-containing melamine resins.

[0038] The phenolic resin as a curing agent and the epoxy resin are preferably blended so that the equivalent ratio (EP) / (OH) of the number of epoxy groups (EP) in the epoxy resin molding material to the number of phenolic hydroxyl groups (OH) in the total phenolic resin is 0.8 or more and 1.3 or less. When the equivalent ratio is within the above range, sufficient curing properties can be obtained when the resulting epoxy resin molding material is molded. However, when a resin other than the phenolic resin that can react with the epoxy resin is used in combination, the equivalent ratio can be adjusted appropriately.

[0039] [Inorganic Filler] (Fiber-like or needle-like filler) The epoxy resin molding material contains a fibrous or needle-like filler as the inorganic filler.

[0040] The lower limit of the volume average fiber length of the fibrous or needle-like filler is, for example, 5 μm or more, preferably 10 μm or more, more preferably 30 μm or more, and even more preferably 50 μm or more. This can improve the strength of the material. On the other hand, the upper limit of the volume average fiber length of the fibrous or needle-like filler is, for example, 500 μm or less, preferably 450 μm or less, and more preferably 400 μm or less. This can improve the moldability of the material.

[0041] When the volume average fiber length of the fibrous or needle-like filler is L and the number average fiber diameter of the fibrous or needle-like filler is D, the aspect ratio is defined as L / D. The lower limit of L / D of the fibrous or needle-like filler is, for example, 3 or more, preferably 10 or more, and more preferably 15 or more. This can further improve the flexural modulus. Also, toughness can be improved. On the other hand, the upper limit of L / D of the fibrous or needle-like filler is, for example, 100 or less, preferably 70 or less, and more preferably 50 or less. This can improve the moldability of the material.

[0042] (Procedure A for measuring volume-average fiber length) After dissolving an epoxy resin molding material in acetone to remove the resin component, the insoluble matter is dispersed on a glass plate, and the filler in the insoluble matter is photographed using an optical microscope, and the fiber length is measured using an image analyzer. The average fiber length based on the fiber volume of 100 fillers, starting from the longest fiber length, is taken as the volume-average fiber length.

[0043] (Procedure B for Measuring Number Average Fiber Diameter) Using a scanning electron microscope, 100 cross sections of fibrous filler are measured from a cross section of an epoxy resin molding material, and the average of the smallest diameters of each fiber cross section is determined as the number average fiber diameter.

[0044] The fibrous or acicular filler may contain, for example, one or more selected from the group consisting of wollastonite fiber, glass fiber, metal fiber, carbon fiber, fibrous aluminum oxide, aramid fiber, silicon carbide whisker, silicon nitride whisker, and potassium titanate whisker. Among these, it is preferable to contain at least one of wollastonite fiber and glass fiber, and it is more preferable to contain wollastonite fiber.

[0045] The lower limit of the content of the fibrous or needle-like filler is, for example, 5% by mass or more, preferably 10% by mass or more, and more preferably 30% by mass or more, based on 100% by mass of the epoxy resin composition. This allows for a further improvement in the flexural modulus. Furthermore, the toughness can also be improved. On the other hand, the upper limit of the content of the fibrous or needle-like filler is not particularly limited, but may be 80% by mass or less, preferably 75% by mass or less, based on 100% by mass of the epoxy resin composition.

[0046] The lower limit of the content of the fibrous or needle-like filler in all inorganic fillers is, for example, 30% by mass or more, preferably 40% by mass or more, and more preferably 50% by mass or more. This can further improve the flexural modulus. Furthermore, toughness can be improved. On the other hand, the upper limit of the content of the fibrous or needle-like filler in all inorganic fillers is not particularly limited, but may be 100% by mass or less.

[0047] (Other inorganic fillers other than fibrous or needle-like fillers) The epoxy resin molding material may contain other inorganic fillers other than fibrous or needle-like fillers. The other inorganic fillers are not particularly limited as long as they have a shape such as a spherical, polygonal, or irregular shape. Specifically, the other inorganic fillers preferably have an aspect ratio of 2 or less, and more preferably are spherical.

[0048] Examples of other inorganic fillers include silica, alumina, kaolin, talc, clay, mica, rock wool, glass powder, glass flakes, glass beads, silicon carbide, silicon nitride, aluminum nitride, carbon black, graphite, titanium dioxide, calcium carbonate, calcium sulfate, barium carbonate, magnesium carbonate, magnesium sulfate, and barium sulfate. These may be used alone or in combination of two or more. Examples of silica that can be used include fused silica such as fused crushed silica and fused spherical silica, and crystalline silica.

[0049] Average particle size D of inorganic filler ５０ is preferably 0.01 μm or more and 75 μm or less, more preferably 0.05 μm or more and 50 μm or less. By setting the average particle size of the inorganic filler within the above range, the filling property in the mold is improved. Furthermore, by setting the upper limit of the average particle size of the inorganic filler to 75 μm or less, the filling property is further improved. Average particle size D ５０ is the volume-converted average particle diameter measured by a laser diffraction measuring device RODOS SR type (SYMPATEC HEROS & RODOS).

[0050] The content of the inorganic filler is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 65% ​​by mass or more, and particularly preferably 75% by mass or more, based on the total amount of the epoxy resin molding material, while the content of the inorganic filler is preferably 93% by mass or less, more preferably 91% by mass or less, and even more preferably 90% by mass or less, based on the total amount of the epoxy resin molding material.

[0051] Furthermore, when an inorganic filler is used in combination with a metal hydroxide such as aluminum hydroxide or magnesium hydroxide, or an inorganic flame retardant such as zinc borate, zinc molybdate, or antimony trioxide, it is desirable that the total amount of the inorganic flame retardant and the inorganic filler be within the range of the content of the inorganic filler.

[0052] [Curing Catalyst] The epoxy resin molding material may contain a curing catalyst if necessary. As the curing catalyst, it is preferable to use one or more selected from the group consisting of amine-based catalysts and phosphorus-based catalysts.

[0053] As the amine catalyst, for example, imidazoles are preferably used. Examples of imidazoles include imidazole, 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-phenyl-4,5-dihydroxyimidazole, 2-phenyl-4,5-dihydroxydimethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole. The compound may include one or more compounds selected from the group consisting of imidazole compounds, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4-methylimidazolyl(1')]-ethyl-s-triazine, an isocyanuric acid adduct of 2,4-diamino-6-[2'-methylimidazolyl(1')]-ethyl-s-triazine, an isocyanuric acid adduct of 2-phenylimidazole, an isocyanuric acid adduct of 2-methylimidazole, and hexamethylenetetramine.

[0054] When the curing catalyst contains an amine catalyst, the lower limit of the content of the amine catalyst is preferably 0.01 mass% or more, more preferably 0.03 mass% or more, and particularly preferably 0.05 mass% or more, based on the total epoxy resin molding material, and the upper limit of the content of the amine catalyst is preferably 2.0 mass% or less, more preferably 1.5 mass% or less, and particularly preferably 1.0 mass% or less, based on the total epoxy resin molding material.

[0055] Examples of phosphorus-based catalysts include phosphorus atom-containing compounds such as organic phosphines, tetra-substituted phosphonium compounds, phosphobetaine compounds, adducts of phosphine compounds and quinone compounds, and adducts of phosphonium compounds and silane compounds.

[0056] Examples of organic phosphines that can be used in the epoxy resin molding material include primary phosphines such as ethylphosphine and phenylphosphine; secondary phosphines such as dimethylphosphine and diphenylphosphine; and tertiary phosphines such as trimethylphosphine, triethylphosphine, tributylphosphine and triphenylphosphine.

[0057] Examples of the tetra-substituted phosphonium compound that can be used in the epoxy resin molding material include compounds represented by the following general formula (4).

[0058] (In the above general formula (4), P represents a phosphorus atom. R ４ , R ５ , R ６ and R ７ represents an aromatic group or an alkyl group. A represents the anion of an aromatic organic acid having at least one functional group selected from a hydroxyl group, a carboxyl group, and a thiol group on the aromatic ring. AH represents an aromatic organic acid having at least one functional group selected from a hydroxyl group, a carboxyl group, and a thiol group on the aromatic ring. x and y are numbers from 1 to 3, z is a number from 0 to 3, and x = y.

[0059] The compound represented by general formula (4) can be obtained, for example, but not limited to, as follows. First, a tetra-substituted phosphonium halide, an aromatic organic acid, and a base are mixed uniformly in an organic solvent, and an aromatic organic acid anion is generated in the solution system. Next, water is added to precipitate the compound represented by general formula (4). In the compound represented by general formula (4), the R bonded to the phosphorus atom ４ , R ５ , R ６ and R ７is preferably a phenyl group, AH is a compound having a hydroxyl group on an aromatic ring, i.e., a phenol, and A is an anion of the phenol. Examples of the phenol include monocyclic phenols such as phenol, cresol, resorcinol, and catechol, condensed polycyclic phenols such as naphthol, dihydroxynaphthalene, and anthraquinol, bisphenols such as bisphenol A, bisphenol F, and bisphenol S, and polycyclic phenols such as phenylphenol and biphenol.

[0060] Examples of the phosphobetaine compound used as a curing catalyst include compounds represented by the following general formula (5).

[0061] (In the above general formula (5), R ８ is an alkyl group having 1 to 3 carbon atoms, R ９ represents a hydroxyl group, f is a number from 0 to 5, and g is a number from 0 to 3.

[0062] The compound represented by general formula (5) can be obtained, for example, as follows: First, a triaromatic-substituted phosphine, which is a tertiary phosphine, is brought into contact with a diazonium salt to substitute the diazonium group of the diazonium salt with the triaromatic-substituted phosphine. However, the method is not limited to this.

[0063] Examples of the adduct of a phosphine compound and a quinone compound used as a curing catalyst include compounds represented by the following general formula (6).

[0064] (In the above general formula (6), P represents a phosphorus atom. R １０ , R １１ and R １２ represents an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and may be the same or different. １３ , R １４ and R １５ represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and may be the same or different from each other; R １４ and R １５may be bonded to form a cyclic structure.)

[0065] The phosphine compound used in the adduct of a phosphine compound and a quinone compound is preferably, for example, triphenylphosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, trinaphthylphosphine, tris(benzyl)phosphine, etc., which is unsubstituted or has a substituent such as an alkyl group or alkoxy group on the aromatic ring, and the substituent such as the alkyl group or alkoxy group has a carbon number of 1 to 6. From the viewpoint of availability, triphenylphosphine is preferred.

[0066] The quinone compound used in the adduct of a phosphine compound and a quinone compound includes benzoquinone and anthraquinones, and among them, p-benzoquinone is preferred from the viewpoint of storage stability.

[0067] The adduct of a phosphine compound and a quinone compound can be produced by contacting and mixing the organic tertiary phosphine and the benzoquinone in a solvent that can dissolve both of them. The solvent is preferably a ketone such as acetone or methyl ethyl ketone, which has low solubility in the adduct, but is not limited thereto.

[0068] In the compound represented by general formula (6), R bonded to the phosphorus atom １０ , R １１ and R １２ is a phenyl group, and R １３ , R １４ and R １５ is a hydrogen atom, that is, a compound obtained by adding 1,4-benzoquinone and triphenylphosphine, is preferred in that it reduces the hot elastic modulus of the cured product of the epoxy resin molding material.

[0069] Examples of the adduct of a phosphonium compound and a silane compound used as a curing catalyst include compounds represented by the following general formula (7).

[0070] (In the above general formula (7), P represents a phosphorus atom, and Si represents a silicon atom. R １６ , R１７ , R １８ and R １９ and each represent an organic group having an aromatic ring or a heterocyclic ring, or an aliphatic group, and may be the same or different. ２０ is the group Y ２ and Y ３ is an organic group that bonds to ２１ is the group Y ４ and Y ５ is an organic group that bonds to ２ and Y ３ represents a group formed by releasing a proton from a proton-donating group, and a group Y ２ and Y ３ is bonded to a silicon atom to form a chelate structure. ４ and Y ５ represents a group formed by releasing a proton from a proton-donating group, and a group Y ４ and Y ５ is bonded to a silicon atom to form a chelate structure. ２０ , and R ２１ may be the same or different, and Y ２ , Y ３ , Y ４ and Y ５ may be the same or different. １ is an organic group having an aromatic ring or a heterocyclic ring, or an aliphatic group.

[0071] In general formula (7), R １６ , R １７ , R １８ and R １９ Examples of the alkyl group include a phenyl group, a methylphenyl group, a methoxyphenyl group, a hydroxyphenyl group, a naphthyl group, a hydroxynaphthyl group, a benzyl group, a methyl group, an ethyl group, an n-butyl group, an n-octyl group, and a cyclohexyl group. Among these, an aromatic group having a substituent such as an alkyl group, an alkoxy group, or a hydroxyl group, such as a phenyl group, a methylphenyl group, a methoxyphenyl group, a hydroxyphenyl group, or a hydroxynaphthyl group, or an unsubstituted aromatic group is more preferred.

[0072] In addition, in the general formula (7), R ２０ Is Y ２ and Y ３ Similarly, R ２１ is the group Y ４ and Y ５ is an organic group that bonds to ２ and Y ３ is a group formed by releasing a proton from a proton-donating group, and the group Y ２ and Y ３ is bonded to a silicon atom to form a chelate structure. ４ and Y ５ is a group formed by releasing a proton from a proton-donating group, and the group Y ４ and Y ５ is bonded to a silicon atom to form a chelate structure. ２０ and R ２１ may be the same or different, and the group Y ２ , Y ３ , Y ４ , and Y ５ may be the same or different. ２ -R ２０ -Y ３ - and -Y ４ -R ２１ -Y ５The group represented by - is constituted by a group formed by a proton donor releasing two protons, and as the proton donor, an organic acid having at least two carboxyl groups or hydroxyl groups in the molecule is preferred, and an aromatic compound having at least two carboxyl groups or hydroxyl groups on adjacent carbons constituting an aromatic ring is more preferred, and an aromatic compound having at least two hydroxyl groups on adjacent carbons constituting an aromatic ring is more preferred, and examples thereof include catechol, pyrogallol, 1,2-dihydro- Examples of the dihydroxynaphthalene include xynaphthalene, 2,3-dihydroxynaphthalene, 2,2'-biphenol, 1,1'-bi-2-naphthol, salicylic acid, 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, chloranilic acid, tannic acid, 2-hydroxybenzyl alcohol, 1,2-cyclohexanediol, 1,2-propanediol, and glycerin. Of these, catechol, 1,2-dihydroxynaphthalene, and 2,3-dihydroxynaphthalene are more preferred.

[0073] In addition, Z in the general formula (7) １ represents an organic group or an aliphatic group having an aromatic ring or a heterocyclic ring, and specific examples thereof include aliphatic hydrocarbon groups such as methyl, ethyl, propyl, butyl, hexyl, and octyl groups; aromatic hydrocarbon groups such as phenyl, benzyl, naphthyl, and biphenyl groups; glycidyloxy groups such as glycidyloxypropyl, mercaptopropyl, and aminopropyl groups; mercapto groups; alkyl groups having amino groups; and reactive substituents such as vinyl groups. Among these, methyl, ethyl, phenyl, naphthyl, and biphenyl groups are more preferred in terms of thermal stability.

[0074] In a method for producing an adduct of a phosphonium compound and a silane compound, a silane compound such as phenyltrimethoxysilane and a proton donor such as 2,3-dihydroxynaphthalene are dissolved in a flask containing methanol, and then a sodium methoxide-methanol solution is added dropwise to the solution with stirring at room temperature. A previously prepared solution of a tetra-substituted phosphonium halide such as tetraphenylphosphonium bromide dissolved in methanol is then added dropwise to the solution with stirring at room temperature, resulting in the precipitation of crystals. The precipitated crystals are filtered, washed with water, and vacuum dried to obtain an adduct of a phosphonium compound and a silane compound. However, the method is not limited to this.

[0075] The content of the curing catalyst is preferably 0.05% by mass or more, more preferably 0.08% by mass or more, and particularly preferably 0.10% by mass or more, based on the total epoxy resin molding material. By setting the content of the curing catalyst to the above-mentioned lower limit or more, the curing property of the epoxy resin molding material during transfer molding can be effectively improved. On the other hand, the content of the curing catalyst is preferably 2.0% by mass or less, more preferably 1.0% by mass or less, and particularly preferably 0.5% by mass or less, based on the total epoxy resin molding material. By setting the content of the curing catalyst to the above-mentioned upper limit or less, the fluidity during sealing can be improved, contributing to improved filling properties.

[0076] [Wax] The epoxy resin molding material may contain wax as a release agent, if necessary. Examples of wax include natural waxes such as carnauba wax, synthetic waxes such as ester wax, Montan acid ester wax, and oxidized polyethylene wax, and higher fatty acids and metal salts thereof such as zinc stearate.

[0077] The amount of wax blended is, for example, 0.05% by mass or more and 2.0% by mass or less, based on the total epoxy resin molding material. The lower limit of the amount of wax blended is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, based on the total epoxy resin molding material. The upper limit of the amount of wax blended is preferably 1.5% by mass or less, more preferably 1.0% by mass or less, based on the total epoxy resin molding material. By blending the wax in the above range, the obtained epoxy resin molding material has excellent fluidity and filling ability during transfer molding.

[0078] [Coupling Agent] The epoxy resin molding material may contain a coupling agent such as a silane coupling agent, if necessary, such as epoxysilane, aminosilane, ureidosilane, or mercaptosilane.

[0079] Examples of epoxy silanes include γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. Examples of aminosilanes include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, N-phenylγ-aminopropyltriethoxysilane, N-phenylγ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, N-6-(aminohexyl)3-aminopropyltrimethoxysilane, and N-(3-(trimethoxysilylpropyl)-1,3-benzenedimethanane. Examples of ureidosilanes include γ-ureidopropyltriethoxysilane and hexamethyldisilazane. Primary aminosilanes include Latent aminosilane coupling agents in which the amino moiety is protected by reaction with a ketone or aldehyde may also be used. Furthermore, the aminosilane may have a secondary amino group. Examples of mercaptosilanes include γ-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and silane coupling agents that exhibit the same function as mercaptosilane coupling agents upon thermal decomposition, such as bis(3-triethoxysilylpropyl)tetrasulfide and bis(3-triethoxysilylpropyl)disulfide. These silane coupling agents may also be blended after being subjected to a hydrolysis reaction in advance. These silane coupling agents may be used alone or in combination of two or more.

[0080] From the viewpoint of continuous moldability, mercaptosilane is preferred, from the viewpoint of flowability, aminosilane is preferred, and from the viewpoint of adhesion, epoxysilane is preferred.

[0081] The lower limit of the content of a coupling agent such as a silane coupling agent that can be used in an epoxy resin molding material is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and particularly preferably 0.1% by mass or more, based on the total epoxy resin molding material. When the lower limit of the content of a coupling agent such as a silane coupling agent is within the above range, the interfacial strength between the epoxy resin and the inorganic filler is not reduced, and good vibration resistance can be obtained. Furthermore, the upper limit of the content of a coupling agent such as a silane coupling agent is preferably 1% by mass or less, more preferably 0.8% by mass or less, and particularly preferably 0.6% by mass or less, based on the total epoxy resin molding material. When the upper limit of the content of a coupling agent such as a silane coupling agent is within the above range, the interfacial strength between the epoxy resin and the inorganic filler is not reduced, and good vibration resistance can be obtained. Furthermore, when the content of a coupling agent such as a silane coupling agent is within the above range, the water absorption of the cured product of the epoxy resin molding material is prevented from increasing.

[0082] [Other Additives] In addition to the above components, the epoxy resin molding material of the present embodiment may further contain, as necessary, other additives such as a colorant, a flame retardant, a stress reducing agent, an adhesion aid, etc. These may be used alone or in combination of two or more.

[0083] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations may be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and modifications and improvements within the scope of achieving the object of the present invention are included in the present invention.

[0084] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the descriptions of these examples.

[0085] (Examples 1 to 3, Comparative Examples 1 and 2) <Production of tablet-shaped epoxy resin molding material> A material mixture containing the components in the amounts shown in Table 1 below was kneaded with a heated roll, cooled into a sheet, and pulverized to obtain a granular epoxy resin composition. The kneading conditions for the heated roll were a rotation speed of 20 rpm, a temperature of 120°C, and a kneading time of 5 to 10 minutes.

[0086] Regarding the raw materials of the epoxy resin composition, the details of each component in Table 1 are as follows: Fibrous or needle-like filler: glass fiber (manufactured by Nitto Boseki Co., Ltd., CS3E479) Other inorganic filler: crushed silica (manufactured by Tatsumori Co., Ltd., RD-8) Colorant: carbon black Epoxy resin: novolac epoxy resin (manufactured by DIC Corporation, N680) Curing agent: phenol novolac resin 1 (manufactured by Sumitomo Bakelite Co., Ltd., PR51470) Curing agent: phenol novolac resin 2 (manufactured by Sumitomo Bakelite Co., Ltd., PR51714) Curing catalyst: amine catalyst (manufactured by Shikoku Chemicals Co., Ltd., 2PZ-PW) Wax: carnauba wax Wax: calcium stearate Stress reducing agent: organically modified silicone oil (manufactured by Dow Chemicals, FZ-3730) Adhesion aid: triazine compound (manufactured by Shikoku Chemicals Co., Ltd., VD-5)

[0087] The epoxy resin composition obtained above was tableted using a tablet machine (BARPRESS manufactured by Kikusui Seisakusho Co., Ltd.) under the molding pressure and compression time conditions shown in Table 2 to obtain tablets weighing 8 g, with a tablet diameter of 14 mm and a tablet height of 29 mm. In this manner, tablet-shaped epoxy resin molding materials (tablets) with different compression ratios were prepared in Examples 1 to 3 and Comparative Examples 1 and 2.

[0088] <Compressibility> The obtained tablet-shaped epoxy resin molding material was measured for specific gravity G, mass M (g), and volume V (cm ３ The compressibility (%) was calculated using the measured G, M, and V according to the formula: [(M / G) / V] x 100. The results are shown in Table 2.

[0089] <Volume-average fiber length> After dissolving the epoxy resin molding material in acetone to remove the resin component, the insoluble portion was dispersed on a glass plate, and the filler in the insoluble portion was photographed using an optical microscope and the fiber length was measured using an image analyzer. The average fiber length, defined by the following formula based on the fiber volume of 100 fillers, starting from the longest fiber length, was taken as the number-average fiber length (μm). The results are shown in Table 2. Lv = Σ(L × v) / Σv, where Σ represents the aggregate, L represents the length of each fiber, and v represents the volume of each fiber.

[0090]

[0091] The obtained epoxy resin compositions and tablet-shaped epoxy resin molding materials were evaluated for the following items.

[0092]

[0093] <Spiral flow> Using a low-pressure transfer molding machine (KTS-15, manufactured by Kotaki Seiki Co., Ltd.), the obtained epoxy resin composition was injected into a spiral flow measurement mold conforming to EMMI-1-66 under conditions of a mold temperature of 175°C, an injection pressure of 6.9 MPa, and a dwell time of 120 seconds, and the flow length was measured.

[0094] The obtained tablets were injection molded using a transfer molding machine under the conditions of a mold temperature of 175°C, an injection pressure of 9.8 MPa, and a curing time of 120 seconds to obtain test specimens as cured products measuring 10 mm in width, 4 mm in thickness, and 80 mm in length. The flexural modulus (GPa) of the obtained test specimens at room temperature was measured in accordance with JIS K 6911.

[0095] <K1c> According to the KIc method specified in ASTM D5045-14, the obtained tablet-shaped epoxy resin molding material (columnar tablet) was cut to a length of 50 mm, a width B of 5 mm, and a thickness W of 10 mm. A notch 3.5 mm deep in the thickness direction was formed in the center of the length direction, and the material was cured at 175°C for 4 hours to obtain a cured product. Furthermore, a scratch 0.1 mm deep in the thickness direction was made with a razor at the tip of the notch of the cured product, and a test piece having a total crack length a = 3.6 mm was prepared. Thereafter, as shown in the outline in Figure 1, a three-point bending test was performed on the obtained test piece 10 using a tension-compression testing machine (Orientec STB-1225S Tensilon) at a measurement temperature of 25°C, a speed of 10 mm / min, and a support distance S = 40 mm, and the fracture toughness value (K1c (MPa m １／２ )) was calculated. Ｑ is the maximum load (N). The tension and compression testing machine in FIG. 1 is equipped with a loading pin 12 with a diameter of 10 mm and two round supports 14 with rounded edges. Ｃ = ((P Ｑ × S) / (B × W ３／２ )) × f(a / W) where f(a / W) = (3(a / W) １／２ [1.99-(a / W) (1-a / W) {2.15-3.9(a / W)+2.7(a / W) ２ ]) / (2{1+2(a / W)}{1-(a / W)} ３／２ When the fracture toughness value of Comparative Example 1 calculated as above is normalized to 1.0, the relative fracture toughness values ​​of Examples 1 to 3 and Comparative Examples 1 and 2 are shown in Table 2.

[0096] <Evaluation of Breakability During Transportation> Breakability during transportation was evaluated as follows. A number of the obtained tablets were placed in a box, and a transportation experiment was conducted in which a predetermined vibration was applied for a predetermined time. The height of the tablets before and after the transportation experiment was measured with a vernier caliper. If the standard deviation of the tablet height after transportation was within 20% of the average tablet height before transportation (immediately after molding), it was determined that there was little breakage during transportation and that breakability during transportation was good, and if it exceeded 20%, it was determined that breakability during transportation was poor.

[0097] The above results show that the epoxy resin molding materials of Examples 1 to 3 exhibited better resistance to breakage during transportation than Comparative Example 1. It was also found that the epoxy resin molding materials of Examples 1 to 3 had higher fracture toughness and mechanical strength than Comparative Example 2. The epoxy resin molding materials of Examples 1 to 3 can be suitably used for magnet fixing, electronic control unit sealing, coil sealing, or stator core sealing.

[0098] This application claims priority based on Japanese Patent Application No. 2024-058574, filed April 1, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0099] 10 Test piece 12 Loading pin 14 Round support

Claims

1. A tablet-shaped epoxy resin molding material, Epoxy resin, and a fibrous or acicular filler, The cross-sectional area is 3 cm ２ More than 100cm ２ is as follows: The specific gravity of the tablet-shaped epoxy resin molding material measured in accordance with JIS 6911:2006 is G, the mass is M (g), and the volume is V (cm ３ ), the compression ratio calculated from [(M / G) / V]×100 is 70% or more and 95% or less, The volume average fiber length of the fibrous or needle-like filler, as measured by the following procedure A, is 5 μm or more and 500 μm or less. Epoxy resin molding material in tablet form. (Procedure A) The tablet-shaped epoxy resin molding material is dissolved in acetone to remove the resin component, and the insoluble matter is dispersed on a glass plate. The filler in the insoluble matter is photographed using an optical microscope, and the fiber length is measured using an image analyzer. The volume-average fiber length is the average fiber length of the 100 longest fillers, based on the fiber volume.

2. A tablet-shaped epoxy resin molding material, Epoxy resin, and a fibrous or acicular filler, The cross-sectional area is 3 cm 2 or more and 100 cm 2 or less, the tablet-shaped epoxy resin molding material has a compressibility calculated from [(M / G) / V] x 100, where G is the specific gravity, M (g) is the mass, and V (cm 3 ) is the volume, as measured in accordance with JIS 6911:2006, of 70% or more and 95% or less; When the volume average fiber length of the fibrous or needle-like filler measured by the following procedure A is L and the number average fiber diameter of the fibrous or needle-like filler measured by the following procedure B is D, A tablet-shaped epoxy resin molding material having an L / D ratio of 3 or more and 100 or less. (Procedure A) The tablet-shaped epoxy resin molding material is dissolved in acetone to remove the resin component, and the insoluble matter is dispersed on a glass plate. The filler in the insoluble matter is photographed using an optical microscope, and the fiber length is measured using an image analyzer. The volume-average fiber length is the average fiber length of the 100 longest fillers, based on the fiber volume. (Procedure B) Using a scanning electron microscope, 100 cross sections of the fibrous filler are measured in the cross section of the tablet-shaped epoxy resin molding material, and the average of the smallest diameters of the respective fiber cross sections is determined as the number average fiber diameter.

3. 3. The tablet-shaped epoxy resin molding material according to claim 1 or 2, A tablet-shaped epoxy resin molding material, wherein the fibrous or acicular filler comprises one or more selected from the group consisting of wollastonite fiber, glass fiber, metal fiber, carbon fiber, fibrous aluminum oxide, aramid fiber, silicon carbide whisker, silicon nitride whisker, and potassium titanate whisker.

4. 3. The tablet-shaped epoxy resin molding material according to claim 1 or 2, A tablet-shaped epoxy resin molding material having a spiral flow of 20 cm or more, as measured according to the following procedure. (procedure) Using a low-pressure transfer molding machine, the tablet-shaped epoxy resin molding material is injected into a spiral flow measurement mold conforming to EMMI-1-66 under conditions of a mold temperature of 175°C, an injection pressure of 6.9 MPa, and a curing time of 120 seconds, and the flow length (cm) is measured.

5. 3. The tablet-shaped epoxy resin molding material according to claim 1 or 2, A tablet-shaped epoxy resin molding material, wherein the content of the fibrous or needle-like filler is 5% by mass or more and 80% by mass or less, based on 100% by mass of the tablet-shaped epoxy resin molding material.

6. 3. The tablet-shaped epoxy resin molding material according to claim 1 or 2, A tablet-shaped epoxy resin molding material, wherein the epoxy resin comprises a cresol novolac type epoxy resin and / or a bisphenol A type epoxy resin.

7. 3. The tablet-shaped epoxy resin molding material according to claim 1 or 2, A tablet-shaped epoxy resin molding material containing one or more curing catalysts selected from the group consisting of amine-based catalysts and phosphorus-based catalysts.

8. 3. The tablet-shaped epoxy resin molding material according to claim 1 or 2, 5 cm ３ More than 1500cm ３ Epoxy resin molding compound in tablet form having the following volume:

9. 3. The tablet-shaped epoxy resin molding material according to claim 1 or 2, A tablet-shaped epoxy resin molding compound used for fixing magnets, sealing electronic control units, coils, or stator cores.

10. A columnar tablet molded from the tablet-shaped epoxy resin molding material according to claim 1 or 2.

11. A step of melt-kneading an epoxy resin composition containing an epoxy resin and a fibrous or needle-like filler to obtain an epoxy resin molding material; and a step of obtaining a columnar tablet using the obtained epoxy resin molding material, The cross-sectional area of ​​the pillar-shaped tablet is 3 cm ２ More than 100cm ２ is as follows: The specific gravity of the columnar tablet measured in accordance with JIS 6911:2006 is G, the mass is M (g), and the volume is V (cm ３ ), the compression ratio calculated from [(M / G) / V]×100 is 70% or more and 95% or less, The volume average fiber length of the fibrous or needle-like filler, as measured by the following procedure A, is 5 μm or more and 500 μm or less. Method for manufacturing pillar-shaped tablets. (Procedure A) The tablet-shaped epoxy resin molding material is dissolved in acetone to remove the resin component, and the insoluble matter is dispersed on a glass plate. The filler in the insoluble matter is photographed using an optical microscope, and the fiber length is measured using an image analyzer. The volume-average fiber length is the average fiber length of the 100 longest fillers, based on the fiber volume.

12. A method for producing an epoxy resin molding material, comprising: melt-kneading an epoxy resin composition containing an epoxy resin and a fibrous or needle-like filler; and a step of obtaining a columnar tablet using the obtained epoxy resin molding material, The cross-sectional area of ​​the pillar-shaped tablet is 3 cm 2 or more and 100 cm 2 or less, the columnar tablet has a compressibility of 70% or more and 95% or less, calculated from [(M / G) / V] x 100, where G is the specific gravity, M (g) is the mass, and V (cm 3 ) is the volume, as measured in accordance with JIS 6911:2006; When the volume average fiber length of the fibrous or needle-like filler measured by the following procedure A is L and the number average fiber diameter of the fibrous or needle-like filler measured by the following procedure B is D, L / D is 3 or more and 100 or less, Method for manufacturing pillar-shaped tablets. (Procedure A) The tablet-shaped epoxy resin molding material is dissolved in acetone to remove the resin component, and the insoluble matter is dispersed on a glass plate. The filler in the insoluble matter is photographed using an optical microscope, and the fiber length is measured using an image analyzer. The volume-average fiber length is the average fiber length of the 100 longest fillers, based on the fiber volume. (Procedure B) Using a scanning electron microscope, 100 cross sections of the fibrous filler are measured in the cross section of the tablet-shaped epoxy resin molding material, and the average of the smallest diameters of the respective fiber cross sections is determined as the number average fiber diameter.