TWI696656B - Epoxy resin molding material, molded product and cured molded product - Google Patents

Abstract

The present invention provides an epoxy resin molding material including: an epoxy resin, a phenol-based curing agent, an insulating inorganic filler and a silane coupling agent, wherein the silane coupling agent includes a silane coupling agent containing a phenyl group, the epoxy resin includes an epoxy resin including a mesogen skeleton, and a content of the epoxy resin including the mesogen skeleton with respect to the entire epoxy resin is 50 mass% or more. The present invention also provides a molded product prepared by press molding the epoxy resin molding material and a cured molded product prepared by postcuring the molded product with heating.

Description

Epoxy resin molding materials, moldings and molding hardened objects

The present invention relates to epoxy resin molding materials, moldings and molding hardened materials.

In recent years, industrial motors and automotive motors and inverters have been rapidly developed to achieve higher output and miniaturization, and the characteristics required for insulating materials have also become quite demanding. Among them, with the miniaturization and high-density conductors, the amount of heat generated by them becomes larger, so how to dissipate heat becomes an important problem to be solved. Insulating materials used for such motors and inverters are widely used in terms of insulation performance, ease of molding, and heat resistance.

As a thermosetting resin having high thermal conductivity, Japanese Patent No. 4118691 proposes a cured product of a resin composition containing an epoxy resin having a liquid crystal matrix. An epoxy resin having a liquid crystal matrix is disclosed in, for example, Japanese Patent No. 4619770, Japanese Patent Laid-Open No. 2010-241797, and Japanese Patent Laid-Open No. 2011-74366. Also, as having high thermal conductivity and low softening point (melting point) JP 2007-332196 has proposed an epoxy resin with a specific structure.

When the thermosetting resin is to be made into an insulating material having excellent thermal conductivity, there is a method of using a composite material obtained by mixing an insulating filler material with high thermal conductivity into a thermosetting resin. As insulating filler materials, such as alumina, magnesium oxide, beryllium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, aluminum fluoride, calcium fluoride and other inorganic ceramic powders Most of them have been fully studied.

However, when such an insulating inorganic filler is mixed with a thermosetting resin, as the filling amount increases, the viscosity of the resin composition before molding also increases remarkably, so there is a tendency to deteriorate the operability. Therefore, it becomes difficult to uniformly disperse the insulating inorganic filler in the resin composition. In addition, the affinity between the thermosetting resin of the organic substance and the insulating inorganic filler often causes problems, and holes may occur at the interface between the thermosetting resin and the insulating inorganic filler. Therefore, a composite material containing a thermosetting resin and an insulating inorganic filler may suffer from low thermal conductivity and deteriorated long-term reliability.

The present invention has been completed in light of the above-mentioned related conditions, and the problem to be solved by one embodiment of the present invention is to provide an epoxy resin molding material that can exhibit high thermal conductivity after curing, and is obtained by using the molding material Molded products and formed hardened products.

In order to solve the aforementioned problems, the specific technical means are as follows.

<1> An epoxy resin molding material containing an epoxy resin, a phenolic hardener, an insulating inorganic filler, and a silane coupling agent; the silane coupling agent includes a silane coupling agent having a phenyl group; the epoxy resin includes The epoxy resin having a liquid crystal matrix; the ratio of the epoxy resin having a liquid crystal matrix is 50% by mass or more in the entire epoxy resin.

<2> The epoxy resin molding material according to <1>, wherein the phenol-based hardener contains a compound selected from the following general formula (I-1) and the following general formula (I-2 ) A compound of at least one structural unit represented by the group formed.

In the general formulae (I-1) and (I-2), R ¹ each independently represents an alkyl group, an aryl group or an aralkyl group. R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group or an aralkyl group. m independently represents an integer of 0~2. n independently represents an integer of 1-7.

<3> The epoxy resin molding material according to <1>, wherein the phenolic hardener contains the following compound: A compound having a structure represented by at least one of the group consisting of the general formula (II-1) to the general formula (II-4).

In the general formulae (II-1) to (II-4), m and _n are each independently a positive integer, and represent the number of respective structural units. In addition, _Ar represents a group represented by any one of the following general formulas (II-a) and (II-b).

In the general formulae (II-a) and (II-b), R ¹¹ and R ¹⁴ each independently represent a hydrogen atom or a hydroxyl group. R ¹² and R ¹³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

<4> The epoxy resin molding material according to any one of <1> to <3>, wherein the epoxy resin molding material is in the A-stage state.

<5> The epoxy resin molding material according to <4>, wherein the mass reduction rate after heating at 180° C. for 1 hour is 0.1% by mass or less.

<6> The epoxy resin molding material according to any one of <1> to <5>, wherein the silane coupling agent having a phenyl group includes a silane in which the phenyl group is directly bonded to a silicon atom (Si) Coupling agent.

<7> The epoxy resin molding material according to any one of <1> to <6>, wherein the amount of coating of silicon atoms derived from the silane coupling agent is per unit specific surface area of the insulating inorganic filler It is 5.0×10 ^-6 mol/m ² ~10.0×10 ^-6 mol/m ² .

<8> The epoxy resin molding material according to any one of <1> to <7>, wherein the insulating inorganic filler includes at least one selected from the group consisting of magnesium oxide and aluminum oxide .

<9> The epoxy resin molding material according to any one of <1> to <8>, wherein the content of the insulating inorganic filler is 60% by volume to 90% by volume in the solid content.

<10> The epoxy resin molding material according to any one of <1> to <9>, wherein the ratio of the epoxy resin having a liquid crystal matrix is 90% by mass in the entire epoxy resin the above.

<11> A molded article produced by press-forming the epoxy resin molding material according to any one of <1> to <10>.

<12> A molded hardened product obtained by heating the molded product described in <11> and post-hardening.

According to an embodiment of the present invention, it is possible to provide an epoxy resin molding material that can exhibit high thermal conductivity after curing, a molded product and a molded cured product using the molding material.

Hereinafter, embodiments of the epoxy resin molding material, molded product, and molded cured product of the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the embodiments described below, the constituent elements (including element steps, etc.) are not necessary except when specifically indicated. The numerical value and the range are also the same, and do not limit the present invention.

The numerical range indicated by "~" in this specification means a range in which the numerical values described before and after "~" are included as the minimum value and the maximum value, respectively. In addition, the amount of each component in the composition of this specification, when there are several substances corresponding to each component in the composition, unless specifically excluded, it means the total of the several substances present in the composition the amount.

In this specification, among the numerical ranges described in the step formula, the upper limit or the lower limit described in one numerical range can also be replaced by the upper limit or the lower limit of the numerical range described in the other stage. In addition, in the numerical range described in this specification, the upper limit value or the lower limit value of the numerical range can also be replaced with the numerical values shown in the examples.

The particle size of each component in the composition of this specification, when there are several types of particles corresponding to each component in the composition, unless otherwise excluded, it means the numerical value of the mixture of the several types of particles present in the composition .

<Epoxy resin molding material>

The epoxy resin molding material of this embodiment type contains epoxy resin, phenolic hardener, insulating inorganic filler, and silane coupling agent; The silane coupling agent includes a silane coupling agent having a phenyl group; the epoxy resin includes an epoxy resin having a liquid crystal matrix; the ratio of the epoxy resin having a liquid crystal matrix is 50% of the entire epoxy resin The quality is above %.

With the epoxy resin molding material of this embodiment, it can exhibit high thermal conductivity after curing.

Hereinafter, each component contained in the epoxy resin molding material of the present embodiment will be described in detail.

<epoxy resin>

The epoxy resin molding material of this embodiment contains epoxy resin. In this embodiment, the epoxy resin includes an epoxy resin having a liquid crystal matrix.

In the present embodiment, the ratio of the epoxy resin having a liquid crystal matrix is 50% by mass or more in the entire epoxy resin. By setting the ratio of the epoxy resin having a liquid crystal matrix to 50% by mass or more in the entire epoxy resin, the high thermal conductivity of the epoxy resin molding material of the present embodiment after hardening is improved.

In the whole epoxy resin, the ratio of the epoxy resin having a liquid crystal-based skeleton is preferably 90% by mass or more, more preferably 95% by mass or more, and still more preferably, the epoxy resin substantially has a liquid-crystal-based skeleton The epoxy resin.

The so-called liquid crystal matrix in the present embodiment means a molecular structure capable of expressing liquid crystallinity. Specific examples include biphenyl, phenyl benzoate, azobenzene, stilbene, and the like, and derivatives thereof. Epoxy resins with a liquid crystal matrix tend to form high-order structures, and when forming molding materials, they tend to achieve higher thermal conductivity. Here, the high-order structure refers to a state in which the constituent elements are arranged in a microscopic manner, and for example, corresponds to a crystal phase and a liquid crystal phase. The presence or absence of such a high-order structure can be easily determined by observation with a polarizing microscope. That is, when you observe the state of the cross polarizer and find the interference fringes caused by the depolarization, you can judge the existence of the higher-order structure. Higher-order structures usually exist as islands in the resin and form a regional structure. After that, the islands forming the regional structure are called high-order structures. The structural units constituting the higher-order structure are generally bonded by covalent bonds.

Specific examples of epoxy resins having a liquid crystal matrix are described in Japanese Patent No. 4118691. The following shows specific examples of epoxy resins having a liquid crystal matrix, but this embodiment is not limited thereto.

Examples of the epoxy resin having a liquid crystal matrix include biphenyl epoxy resin and 1-(3-methyl-4-epoxyethylmethoxyphenyl)-4-(4-epoxyethylene Methoxyphenyl)-1-cyclohexene, 1-(3-methyl-4-epoxyethylmethoxyphenyl)-4-(4-epoxyethylmethoxyphenyl) -Benzene etc. The biphenyl type epoxy resin is obtained by reacting epichlorohydrin in a biphenol compound by a known method. Examples of such a biphenyl-type epoxy resin include 4,4'-bis(2,3-epoxypropoxy)biphenyl and the like. As such a biphenyl epoxy resin, commercially available products such as YL-6121H (manufactured by Mitsubishi Chemical Corporation) are available. Such The epoxy resin with a liquid crystal matrix can be used alone or in combination of two or more.

The epoxy equivalent of the epoxy resin having a liquid crystal matrix is preferably 130 g/eq to 500 g/eq, more preferably 135 g/eq to 400 g/eq, and even more preferably 140 g/eq to 300 g/eq.

An epoxy resin having a liquid crystal matrix can also be in a state of a prepolymer obtained by partially reacting a part with a hardener or the like. Epoxy resins with a liquid crystal matrix are generally easy to crystallize, and most of them have low solubility in solvents. By polymerizing a part of the epoxy resin having a liquid crystal base skeleton, crystallization can be suppressed. Therefore, the formability is improved.

The epoxy resin molding material of this embodiment can also contain other epoxy resins that do not have a liquid crystal matrix as an epoxy resin. Examples of other epoxy resins include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol AD epoxy resin, hydrogenated bisphenol A epoxy resin, and hydrogenated bisphenol AD resin. Epoxy resin, naphthalene type epoxy resin, and epoxy resin having one epoxy group called reactive diluent.

<phenolic hardener>

The epoxy resin molding material of this embodiment mode contains a phenolic hardener.

The phenolic hardener of the present embodiment can be used as a hardener for epoxy resin, and is not particularly limited. For example, a phenol compound and a phenol resin obtained by phenolizing these phenol compounds can be used.

As phenol compounds, monofunctional compounds such as phenol, o-cresol, m-cresol, and p-cresol can be used; catechol, resorcinol, and p-benzenediol Bifunctional compounds such as phenol; trifunctional compounds such as 1,2,3-pyrogallol, 1,2,4-pyrogallol, 1,3,5-pyrogallol, etc. In addition, phenol novolak resin can also be used as a hardener, and the phenol novolak resin is formed by connecting these phenol compounds with methylene chains and performing phenolization.

As the phenolic hardener, from the viewpoint of thermal conductivity, a bifunctional phenol compound such as catechol, resorcinol, hydroquinone, or the like is preferably used as a methylene chain From the viewpoint of heat resistance, the phenol novolak resin formed by linking is more preferably a phenol novolak resin formed by linking these bifunctional phenol compounds with a methylene chain.

Specific examples of the phenol novolak resin include cresol novolak resin, catechol novolak resin, resorcinol novolak resin, and hydroquinone novolak resin. A resin obtained by phenolization of compounds; two or more phenol compounds obtained by phenolization of catechol resorcinol novolak resin, resorcinol hydroquinone novolak resin, etc. Resin etc.

When the phenol novolak resin is used as the phenolic hardener of the present embodiment, the phenolic hardener preferably contains a compound selected from the following general formula (I-1) and the following general formula (I -2) A compound of at least one structural unit represented by the group formed.

In the above general formulas (I-1) and (I-2), R ¹ each independently represents an alkyl group, an aryl group or an aralkyl group. The alkyl group represented by R ¹ may be linear or branched. The alkyl group, aryl group, and aralkyl group represented by R ¹ may further have a substituent. Examples of substituents that the alkyl group represented by R ¹ can have include aryl groups, halogen atoms, and hydroxyl groups. Examples of the substituent that the aryl group and aralkyl group represented by R ¹ can have include an alkyl group, an aryl group, a halogen atom, and a hydroxyl group.

m is an integer independently representing 0~2. When m is 2, two R ^1s can be the same or different. In this embodiment, m is preferably independently 0 or 1, more preferably 0.

In addition, n independently represents an integer of 1 to 7.

In the above general formulas (I-1) and (I-2), R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group or an aralkyl group. The alkyl groups represented by R ² and R ³ can be linear or branched. The alkyl group, aryl group, and aralkyl group represented by R ² and R ³ may further have a substituent. Examples of substituents that the alkyl groups represented by R ² and R ³ can have include aryl groups, halogen atoms, and hydroxyl groups. Examples of the substituent that the aryl group and aralkyl group represented by R ² and R ³ can have include an alkyl group, an aryl group, a halogen atom, and a hydroxyl group.

As R ² and R ^{3 of the} present embodiment, from the viewpoint of storage stability and thermal conductivity, a hydrogen atom, an alkyl group or an aryl group is preferred, and a hydrogen atom and an alkyl group having 1 to 4 carbon atoms are more preferred The aryl group having 6 to 12 carbon atoms is further preferably a hydrogen atom. Here, when the alkyl group and the aryl group have a substituent, the carbon number of the alkyl group and the aryl group refers to a value excluding the number of carbon atoms included in the substituent.

The compound having the structural unit represented by the general formula (I-1) can further contain at least one partial structure derived from a phenol compound other than resorcinol. Among the compounds having a structural unit represented by the general formula (I-1), examples of the partial structure derived from phenol compounds other than resorcinol include, for example, phenol, cresol, and catechol. Partial structure of hydroquinone, 1,2,3-benzenetriol, 1,2,4-benzenetriol, and 1,3,5-benzenetriol. In this embodiment, one type of these partial structures can be included alone, or two or more types of these partial structures can be combined.

Also, in the same manner, the compound having the structural unit represented by the general formula (I-2) can further include at least one partial structure derived from a phenol compound other than catechol. Among the compounds having a structural unit represented by the general formula (I-2), examples of the partial structure derived from phenol compounds other than catechol include, for example, phenol, cresol, and resorcinol. Partial structure of hydroquinone, 1,2,3-benzenetriol, 1,2,4-benzenetriol, and 1,3,5-benzenetriol. In this embodiment, a single type of these partial structures can be included, or two or more types of these partial structures can be combined.

Here, the partial structure derived from the phenol compound means that a monovalent group or a divalent group composed of one or two hydrogen atoms from the benzene ring portion of the phenol compound is removed. In addition, the position at which the hydrogen atom is removed is not particularly limited.

Among the compounds having a structural unit represented by the above general formula (I-1), as a partial structure derived from a phenol compound other than resorcinol, from the viewpoint of thermal conductivity and adhesiveness, it is preferably a source From the partial structure of the following phenol compounds: selected from the group consisting of phenol, cresol, catechol, hydroquinone, 1,2,3-benzenetriol, 1,2,4-benzenetriol and 1,3, At least one of the group consisting of 5-pyrogallol. More preferably, it is derived from the partial structure of the phenol compound: at least one selected from the group consisting of catechol and hydroquinone.

In addition, in the compound having the structural unit represented by the general formula (I-1), the content ratio of the partial structure derived from resorcinol is not particularly limited. From the viewpoint of elastic modulus, the content ratio of the partial structure derived from resorcinol relative to the total mass of the compound having the structural unit represented by the general formula (I-1) is preferably 55 mass %the above. Further, from the viewpoint of glass transition temperature (Tg) and linear expansion rate, it is more preferably 60% by mass or more, still more preferably 80% by mass or more, and particularly preferably 90% by mass or more from the viewpoint of thermal conductivity. .

Among the compounds having a structural unit represented by the above general formula (I-2), as a partial structure derived from a phenol compound other than catechol, from the viewpoint of thermal conductivity and adhesiveness, it is preferably a source From the following partial structure of phenol compounds: selected from the group consisting of phenol, cresol, resorcinol, hydroquinone, 1,2,3-benzenetriol, 1,2,4-benzenetriol, and 1,3 ,5- At least one of the group consisting of pyrogallol. More preferably, it is derived from the partial structure of the phenol compound: at least one selected from the group consisting of resorcinol and hydroquinone.

In addition, in the compound having the structural unit represented by the general formula (I-2), the content ratio of the partial structure derived from catechol is not particularly limited. From the viewpoint of the modulus of elasticity, the content ratio of the partial structure derived from catechol relative to the total mass of the compound having the structural unit represented by the general formula (I-2) is preferably 55 mass %the above. Further, from the viewpoint of glass transition temperature (Tg) and linear expansion rate, it is more preferably 60% by mass or more, still more preferably 80% by mass or more, and particularly preferably 90% by mass or more from the viewpoint of thermal conductivity. .

In this embodiment, the compound having a structural unit represented by at least one selected from the group consisting of the aforementioned general formula (I-1) and the aforementioned general formula (I-2), the molecular weight of which is not particularly limited . From the viewpoint of fluidity, the number average molecular weight (Mn) is preferably 2000 or less, more preferably 1500 or less, and still more preferably 350 to 1500. Moreover, the weight average molecular weight (Mw) is preferably 2000 or less, more preferably 1500 or less, and still more preferably 400 to 1500. These Mn and Mw are measured by a general method using gel permeation chromatography (GPC).

In the present embodiment, the compound having a structural unit represented by at least one selected from the group consisting of the above general formula (I-1) and the above general formula (I-2) has no special hydroxyl equivalent limit. From the viewpoint of the crosslink density related to heat resistance, the hydroxyl equivalent, calculated as an average value, is It is preferably 50g/eq to 150g/eq, more preferably 50g/eq to 120g/eq, and even more preferably 55g/eq to 120g/eq. In addition, in the present embodiment, the hydroxyl equivalent refers to a value measured according to Japanese Industrial Standards (JIS) K0070:1992.

In the present embodiment, as the phenolic hardener, a compound having at least one structural unit selected from the group consisting of the general formula (I-1) and the general formula (I-2) is used When the phenolic hardener has a ratio of a compound having at least one structural unit selected from the group consisting of the general formula (I-1) and the general formula (I-2) It is preferably 50% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more.

Furthermore, when phenol novolak resin is used as the phenolic hardener of the present embodiment, the phenol novolak resin preferably contains the following compound selected from the following general formulas (II-1) to (I-4 ) A compound of at least one structure represented by the group formed.

In the above general formulas (II-1) to (II-4), m and n are each independently a positive integer and represent the number of respective structural units; and Ar represents the following general formula (II-a) and The group represented by any one of (II-b).

In the above general formulas (II-a) and (II-b), R ¹¹ and R ¹⁴ each independently represent a hydrogen atom or a hydroxyl group; R ¹² and R ¹³ each independently represent a hydrogen atom or a C1-C8 alkane base.

A compound having a structure represented by at least one selected from the group consisting of the general formula (II-1) to the general formula (II-4) can be subjected to phenol formaldehyde by a divalent phenol compound described later The chemical manufacturing method is produced as a by-product.

The partial structure represented by the above general formulae (II-1) to (II-4) may be included as the main chain skeleton of the compound, or may be included as a part of the side chain. Further, each structural unit constituting a partial structure represented by any of the above general formulas (II-1) to (II-4) can be included randomly, can be included regularly, or can be blocked It is contained likewise. In addition, in the general formulae (II-1) to (II-4), the substitution position of the hydroxyl group is not particularly limited as long as it is on the aromatic ring.

Regarding each of the above general formulas (III-1) to (III-4), Ar in the plural may be all the same atomic group, or may include two or more atomic groups. In addition, Ar represents a group represented by any of the general formulas (II-a) and (II-b).

In the general formulae (II-a) and (II-b), R ¹¹ and R ¹⁴ each independently represent a hydrogen atom or a hydroxyl group, and from the viewpoint of thermal conductivity, a hydroxyl group is preferred. In addition, the substitution positions of R ¹¹ and R ¹⁴ are not particularly limited.

In the above general formula (II-a), R ¹² and R ¹³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Examples of the alkyl groups having 1 to 8 carbon atoms in R ¹² and R ¹³ include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tertiary butyl, Amyl, hexyl, heptyl, and octyl. In addition, in the above general formula (II-a), the substitution positions of R ¹² and R ¹³ are not particularly limited.

Ar in the general formulae (II-1) to (II-4) is preferably at least one selected from the group consisting of the following groups from the viewpoint of achieving more excellent thermal conductivity: source From a group of hydroquinone (in the above general formula (II-a), R ¹¹ is a hydroxyl group and R ¹² and R ¹³ are hydrogen atoms), and a group derived from dihydroxynaphthalene (in the general formula (II-b), R ¹⁴ is hydroxy).

Here, "a group derived from resorcinol" means a divalent group formed by removing two hydrogen atoms from the aromatic ring portion of resorcinol, and the position at which the hydrogen atoms are removed is not particularly limited. In addition, the "group derived from dihydroxynaphthalene" has the same meaning.

Moreover, from the viewpoint of productivity and fluidity of the epoxy resin molding material of the present embodiment, Ar is more preferably derived from a group of resorcinol, and further preferably is selected from the group consisting of the following groups At least one of: a group derived from 1,2-dihydroxybenzene (catechol) and a group derived from 1,3-benzenediol (resorcinol). In particular, from the viewpoint of particularly improving thermal conductivity, it is preferred that Ar contains at least a group derived from resorcinol. In addition, from the viewpoint of particularly improving thermal conductivity, the structural unit represented by the structural unit n preferably contains a group derived from resorcinol.

When a compound having a structure represented by at least one selected from the group consisting of the above general formula (II-1) to the above general formula (II-4) includes a structural unit derived from resorcinol, The content rate of the structural unit derived from resorcinol, from the viewpoint of the elastic modulus, is the total of the compounds having a structure represented by at least one of the general formulas (II-1) to (II-4) above Among the masses, it is preferably 55% by mass or more. From the viewpoint of Tg and the linear expansion coefficient, it is more preferably 60% by mass or more, and still more preferably 80% by mass or more. From the viewpoint of thermal conductivity, particularly preferably 90% by mass or more.

Regarding m and n in the above general formulae (II-1) to (II-4), from the viewpoint of fluidity, it is preferably m/n=20/1 to 1/5, more preferably 20/1 ~5/1, even better is 20/1~10/1. In addition, (m+n) is preferably 20 or less, more preferably 15 or less, and even more preferably 10 or less from the viewpoint of fluidity. In addition, the lower limit of (m+n) is not particularly limited.

A compound having a structure represented by at least one selected from the group consisting of the aforementioned general formula (II-1) to the aforementioned general formula (II-4), in particular, Ar is derived from substituted or unsubstituted benzene di When the phenolic group and any of the groups derived from substituted or unsubstituted dihydroxynaphthalene are compared with phenol resins and the like which are simply phenol-formed, these compounds are selected from the general formula ( II-1) ~ The compound of the structure represented by at least one of the above general formula (II-4) is easier to synthesize, Moreover, there is a tendency to obtain a hardener with a low softening point. Therefore, by including such a phenol resin as a hardener, there are advantages such as easy production and use of epoxy resin molding materials.

In addition, whether the phenol novolak resin has a partial structure represented by any one of the above general formulas (II-1) to (II-4) can be determined by the following method: measurement by electric field desorption ionization mass spectrometry Method (FD-MS), to confirm whether the component corresponding to the partial structure represented by any of the general formulae (II-1) to (II-4) is included as a fragment component.

In the present embodiment, the molecular weight of the compound having a structure represented by at least one selected from the group consisting of general formula (II-1) to general formula (II-4) is not particularly limited. From the viewpoint of fluidity, the number average molecular weight (Mn) is preferably 2000 or less, more preferably 1500 or less, and still more preferably 350 to 1500. Moreover, the weight average molecular weight (Mw) is preferably 2000 or less, more preferably 1500 or less, and still more preferably 400 to 1500.

The Mn and Mw are measured by a general method using gel permeation chromatography.

In this embodiment, the compound having a structure represented by at least one selected from the group consisting of the above general formula (II-1) to the above general formula (II-4) has no particular limitation on its hydroxyl equivalent . From the viewpoint of the cross-linking density related to heat resistance, the hydroxyl group equivalent is preferably 50g/eq to 150g/eq, more preferably 50g/eq to 120g/eq, and even more preferably 55g/ eq~120g/eq.

In the present embodiment, as the phenolic hardener, a compound having a structure represented by at least one selected from the group consisting of the general formula (II-1) to the general formula (II-4) is used , In the phenolic hardener, the ratio of compounds having a structure represented by at least one selected from the group consisting of the general formula (II-1) to the general formula (II-4) is greater than It is preferably 50% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

In the present embodiment, as the phenolic hardener, a compound having at least one structural unit selected from the group consisting of the general formula (I-1) and the general formula (I-2) is used Or when using a compound having a structure represented by at least one selected from the group consisting of the above general formula (II-1) to the above general formula (II-4), the phenolic hardener can also contain the following The monomer of the phenol compound: a phenol compound constituting a compound having a structural unit represented by at least one selected from the group consisting of the general formula (I-1) and the general formula (I-2), or A phenol compound having a structure represented by at least one selected from the group consisting of the general formula (II-1) to the general formula (II-4). The content ratio of the phenol compound monomer (hereinafter, also referred to as "monomer content ratio") is not particularly limited. From the viewpoint of thermal conductivity and formability, the phenolic hardener is preferably 5% by mass to 80% by mass, more preferably 15% by mass to 60% by mass, and even more preferably 20% by mass to 50% by mass .

When the monomer content ratio is 80% by mass or less, the number of monomers that are not related to crosslinking during the curing reaction will be reduced, and the high molecular weight body related to crosslinking There will be more, so there is a tendency to form a higher density cross-linked structure and improve the thermal conductivity. In addition, when the monomer content is 5 mass% or more, it tends to flow during molding, and therefore, there is a tendency that the adhesion with the filler is more improved and more excellent thermal conductivity and heat resistance can be achieved.

The content of the phenolic hardener is not particularly limited. The ratio of the equivalent number of active hydrogen of the phenolic hydroxyl group contained in the phenolic hardener (equivalent number of phenolic hydroxyl group) to the equivalent number of epoxy groups contained in the epoxy resin (equivalent number of phenolic hydroxyl group/ (Equivalent number of epoxy group), preferably 0.5 to 2, more preferably 0.8 to 1.2.

<hardening accelerator>

The epoxy resin molding material of this embodiment type can also contain a hardening accelerator as needed.

By using a phenolic hardener and a hardening accelerator together, the epoxy resin molding material can be hardened more fully. The type and addition amount of the curing accelerator are not particularly limited, and can be appropriately selected from the viewpoints of reaction rate, reaction temperature, and storage property.

Specific examples of the hardening accelerator include imidazole compounds, organic phosphine compounds, tertiary amine compounds, and quaternary ammonium salts. These hardening accelerators can be used alone or in combination of two or more. Among them, from the viewpoint of heat resistance, it is preferably at least one selected from the group consisting of an organic phosphine compound; maleic anhydride, 1,4-benzoquinone, 2,5-methylquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1, 4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone Quinone compounds; diazotoluene, phenol resin and other compounds with π-bonding compounds with intramolecular polarization; and, organic phosphine compounds and tetraphenylboron, tetra-p-toluene borate, tetra-n-butyl Inorganic borate compounds and other organic boron compounds formed by the complex.

Examples of the organic phosphine compound include triphenylphosphine, diphenyl(p-tolyl)phosphine, tri(alkylphenyl)phosphine, tri(alkoxyphenyl)phosphine, and tri(alkyl / Alkoxyphenyl) phosphine, tri (dialkylphenyl) phosphine, tri (trialkylphenyl) phosphine, tri (tetraalkylphenyl) phosphine, tri (dialkoxyphenyl) phosphine , Tris (trialkoxyphenyl) phosphine, tris (tetraalkoxyphenyl) phosphine, trialkyl phosphine, dialkyl aryl phosphine, alkyl diaryl phosphine, etc.

When the epoxy resin molding material of the present embodiment includes a curing accelerator, the content of the curing accelerator in the epoxy resin molding material is not particularly limited. From the viewpoint of fluidity and formability, the content of the curing accelerator is preferably 0.1 to 1.5% by mass of the total mass of the epoxy resin and the phenolic curing agent, and more preferably 0.2 to 1% by mass.

<insulating inorganic filler>

The epoxy resin molding material of this embodiment includes at least one insulating inorganic filler. With this, high thermal conductivity can be achieved.

In this embodiment, the "insulation property" of the inorganic filler refers to the property that the inorganic filler itself does not pass current even if a voltage of about hundreds of volts to thousands of volts is applied. This is because electrons occupy the highest The valence band of the energy level is separated from the next energy band (conduction band) located above it by the nature caused by the huge energy gap.

Specific examples of the insulating inorganic filler include boron nitride, aluminum oxide, silicon oxide, aluminum nitride, magnesium oxide, silicon oxide, aluminum hydroxide, and barium sulfate. Among them, from the viewpoint of fluidity, thermal conductivity, and electrical insulation, it is preferable to include at least one insulating inorganic filler selected from the group consisting of magnesium oxide and aluminum oxide. In addition, when the epoxy resin molding material of this embodiment includes at least one selected from the group consisting of magnesium oxide and alumina as an insulating inorganic filler, the epoxy resin molding material of this embodiment is not Within the range that hinders fluidity, it can further contain boron nitride, silicon oxide, aluminum nitride, etc.

The ratio of at least one insulating inorganic filler selected from the group consisting of magnesium oxide and aluminum oxide in the insulating inorganic filler is preferably 50% by mass, more preferably 80% by mass, further Even better is 90% by mass

When plotting the particle size distribution curve with the particle size as the horizontal axis and the frequency as the vertical axis, the insulating inorganic filler can have a single peak or a plurality of peaks. By using an insulating inorganic filler having a plurality of peaks in the particle size distribution curve, the filling property of the insulating inorganic filler is improved, and the thermal conductivity of the molded hardened product as an epoxy resin molding material is improved.

Insulating inorganic fillers with a single peak when plotting the particle size distribution curve, the insulating inorganic fillers correspond to an average of 50% cumulative from the smaller particle size side of the weight cumulative particle size distribution curve From the viewpoint of thermal conductivity, the particle diameter (D50) is preferably 0.1 to 100 μm, and more preferably 0.1 to 70 μm.

In addition, the insulating inorganic filler having a plurality of peaks in the particle size distribution curve can be formed by combining two or more types of insulating inorganic fillers, and the two or more types of insulating inorganic fillers have different averages Particle size.

In this embodiment, the average particle size (D50) of the insulating inorganic filler is measured using the laser diffraction method. When the weight accumulation particle size distribution curve is drawn from the smaller particle size side, the corresponding weight accumulation to 50% particle size. The particle size distribution measurement using the laser diffraction method can be performed using a laser diffraction scattering particle size distribution measurement device (for example, a product name LS230 manufactured by Beckman Coulter Co., Ltd.).

The content (volume %) of the insulating inorganic filler in the epoxy resin molding material of the present specification is a numerical value obtained by the following formula.

Insulating inorganic filler content (volume %) = {(Ew/Ed)/[(Aw/Ad)+(Bw/Bd)+(Cw/Cd)+(Dw/Dd)+(Ew/Ed) +(Fw/Fd)]}×100.

Here, each variable is as follows.

Aw: Mass composition ratio of epoxy resin (mass %)

Bw: mass composition ratio of phenolic hardener (mass %)

Cw: mass composition ratio of silane coupling agent (mass %)

Dw: mass composition ratio (mass %) of hardening accelerator (optional component)

Ew: mass composition ratio of insulating inorganic filler (mass %)

Fw: mass composition ratio (mass %) of other components (optional components)

Ad: the proportion of epoxy resin

Bd: specific gravity of phenolic hardener

Cd: specific gravity of silane coupling agent

Dd: Specific gravity of hardening accelerator (optional component)

Ed: proportion of insulating inorganic filler

Fd: the proportion of other components (arbitrary components)

The content of the insulating inorganic filler in the epoxy resin molding material is not particularly limited. From the viewpoint of thermal conductivity and moldability, when the total volume of the solid content of the epoxy resin molding material is 100% by volume The content of the insulating inorganic filler is preferably 60% by volume to 90% by volume, and more preferably 70% by volume to 85% by volume. By setting the content of the insulating inorganic filler to 60% by volume or more, higher thermal conductivity can be achieved. On the other hand, by setting the content of the insulating inorganic filler to 90% by volume or less, an epoxy resin molding material excellent in moldability can be obtained.

In addition, in the present embodiment, the solid content of the epoxy resin molding material means the component remaining after the volatile component is removed from the epoxy resin molding material.

<Silane coupling agent>

The epoxy resin molding material of this embodiment contains a silane coupling agent. The silane coupling agent used in this embodiment includes a silane coupling agent having a phenyl group. Silane coupling agent with phenyl, in the silane coupling agent The ratio is preferably 50% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more.

As an effect of containing a silane coupling agent, the surface of the insulating inorganic filler interacts with the epoxy resin surrounding it via the silane coupling agent, thereby improving the fluidity and increasing the thermal conductivity. , Also makes the insulation reliability improved. Among them, the silane coupling agent containing a phenyl group easily interacts with the epoxy resin having a liquid crystal base skeleton, so it can achieve more excellent thermal conductivity. Further, in order to bring the surface of the insulating inorganic filler material close to the epoxy resin surrounding it and achieve excellent thermal conductivity, the silane coupling agent having a phenyl group preferably contains a phenyl group directly bonded to a silicon atom Silane coupling agent on (Si).

The ratio of the silane coupling agent in which the phenyl group is directly bonded to the silicon atom (Si) in the silane coupling agent having a phenyl group is preferably 30% by mass or more, more preferably 50% by mass or more, and still more preferably It is more than 80% by mass.

The type of silane coupling agent containing phenyl is not particularly limited, and commercially available products can also be used. Specific examples of the silane coupling agent having a phenyl group include 3-phenylaminopropyltrimethoxysilane, 3-phenylaminopropyltriethoxysilane, and N-methylanilinopropyl Trimethoxysilane, N-methylanilinopropyltriethoxysilane, 3-phenyliminopropyltrimethoxysilane, 3-phenyliminopropyltriethoxysilane, phenyl Trimethoxysilane, phenyltriethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, triphenylmethoxysilane, triphenyl Base ethoxysilane etc. These silane coupling agents can be used alone or in combination of two or more.

The silane coupling agent may be included in the epoxy resin molding material of the present embodiment, and may exist in a state of being coated on the surface of the insulating inorganic filler material. There is a state where the filler material is separated.

The method of adding a silane coupling agent to the epoxy resin molding material is not particularly limited. Specifically, there are the following methods: when mixing epoxy resins, insulating inorganic fillers and other materials, an overall method of adding a silane coupling agent; after mixing a fixed amount of silane coupling agent in a small amount of resin, The masterbatch method of mixing with other materials such as insulating inorganic fillers; before mixing with other materials such as epoxy resins, mixing the insulating inorganic fillers with silane coupling agents, prior to the insulating inorganic The surface of the filling material is pre-treated with a silane coupling agent, etc. In addition, there are processing methods such as dry method and wet method in the pretreatment method, wherein the dry method is to mix the silane coupling agent stock solution or solution with the insulating inorganic filler at high speed to make the silane coupling agent The method of uniformly dispersing and processing; the wet method is by slurrying the insulating inorganic filler with a dilute solution of silane coupling agent, or immersing the insulating inorganic filler in the silane coupling agent, etc. To apply a silane coupling agent to the surface of the insulating inorganic filler.

In this embodiment, relative to the specific surface area of the insulating inorganic filler, the coating amount of silicon atoms derived from the silane coupling agent is preferably 5.0×10 ^-6 moles/m ² ~10.0×10 ^-6 moles Ears/m ² , more preferably 5.5×10 ^-6 moles/m ² ~9.5×10 ^-6 moles/m ² , and even more preferably 6.0×10 ^-6 moles/m ² ~9.0×10 ^-6 Mohr/m ² .

The method of measuring the coating amount of silicon atoms derived from the silane coupling agent with respect to the specific surface area of the insulating inorganic filler is as follows.

First, as a method of measuring the specific surface area of the insulating inorganic filler, the BET method is mainly used. The BET method refers to a gas adsorption method that adsorbs inert gas molecules such as nitrogen (N ₂ ), argon (Ar), and krypton (Kr) to solid particles, and then determines the specific surface area of the solid particles from the amount of gas molecules adsorbed . The specific surface area can be measured using a specific surface area pore distribution measuring device (for example, SA3100 (model) manufactured by Beckman Coulter Co., Ltd.).

Furthermore, the silicon atoms present on the surface of the insulating inorganic filler and derived from the silane coupling agent can be quantitatively measured by ²⁹ Si Cp/MAS solid-state nuclear magnetic resonance ( ²⁹ Si CP/MAS solid-state NMR). Since the CP/MAS solid-state nuclear magnetic resonance instrument (for example, manufactured by JEOL Ltd., JNM-ECA700 (model)) has a high resolution, even when the insulating inorganic filler material contains silicon oxide, it can still be Silicon atoms derived from silicon oxide as an insulating inorganic filler are distinguished from silicon atoms derived from silane coupling agents.

In addition, when the insulating inorganic filler does not contain silicon oxide, the silicon atoms derived from the silane coupling agent can also be removed by a fluorescent X-ray analyzer (for example, Supermini200 (model) manufactured by Rigaku Corporation). Quantify.

Based on the specific surface area of the insulating inorganic filler obtained in the above manner, and the amount of silicon atoms derived from the silane coupling agent present on the surface of the insulating inorganic filler, the relative to the insulating inorganic filler can be calculated The unit specific surface area is derived from the amount of silicon atoms covered by the silane coupling agent.

<other ingredients>

The epoxy resin molding material of this embodiment type can also contain a mold release agent as required. Examples of the mold release agent include oxidized and non-oxidized polyenes, palm wax, octacosanoic acid, octacosanoic acid, and stearic acid. These release agents can be used alone or in combination of two or more.

In addition, the epoxy resin molding material may contain stress buffering agents such as silicone oil and silicone rubber powder, reinforcing materials such as glass fiber, etc. as needed.

The epoxy resin molding material of this embodiment mode can be prepared by any method as long as various components can be dispersed and mixed. As a general method for preparing an epoxy resin molding material, a method in which a predetermined amount of components are sufficiently mixed with a stirrer and the like, and then melt-kneaded, cooled, and pulverized by a mixing roller, an extruder, or the like can be mentioned. For example, epoxy resin molding can be obtained by kneading, cooling, pulverizing, etc. with a kneader, roller, extruder, etc., which previously heated a predetermined amount of the above components, and heated to 70-140°C in advance. material. If the epoxy resin molding material of the present embodiment is formed into a sheet with a size and quality that meets the molding conditions, it will be more convenient to use.

The epoxy resin molding material of this embodiment is preferably in the A-stage state. With the epoxy resin molding material of this embodiment In the A-stage state, when the epoxy resin molding material of this embodiment is heat-cured, the curing reaction between the epoxy resin and the phenolic hardener is higher than in the case where the epoxy resin molding material is in the B-stage state. The heat of reaction generated increases, and the hardening reaction becomes easy to proceed.

In this embodiment, whether or not the epoxy resin molding material is in the A-stage state is determined by the following criteria.

Put a certain amount of epoxy resin molding material into an organic solvent (tetrahydrofuran, acetone), and the epoxy resin contained in the epoxy resin molding material is soluble in the organic solvent, after a certain period of time, the residue is filtered The insulating inorganic filler materials are filtered and separated. The quality of the residue obtained by filtration and separation after drying was measured. On the other hand, the epoxy resin molding material and the equal amount of epoxy resin molding material subjected to the filtration and separation treatment were subjected to high-temperature treatment, and the quality of the ash content was measured. If the difference between the dried mass of the residue obtained by filtration and separation and the mass of ash obtained by high-temperature treatment is within 0.5% by mass, it is judged that the epoxy resin molding material is in the A-stage state. The quality of ash is measured and calculated based on the Japanese Industrial Standard K7250-1: 2006. In addition, for the epoxy resin molding material that has been judged to be in the A-stage state in advance, the reaction heat with respect to a certain mass is determined by differential scanning calorimetry (DSC, Differential Scanning Calorimetry; for example, manufactured by Perkin Elmer Co., Ltd., Pyris Model)) to be measured and used as a reference value. The epoxy resin molding material prepared afterwards, with respect to a certain mass of reaction heat If the difference between the measured value and the reference value is within ±5%, it is judged as the A-stage state.

In addition, in this embodiment, the definitions of the terms A-stage and B-stage are based on the Japanese Industrial Standard K 6800:1985.

When the epoxy resin molding material of the present embodiment is in the A-stage state, it is preferable that after the epoxy resin molding material in the A-stage state is heated at 180° C. for 1 hour, the mass reduction rate is 0.1% by mass or less. After the epoxy resin molding material in the A-stage state is heated at 180°C for 1 hour, the mass reduction rate is 0.1% by mass or less. This indicates that the epoxy resin molding material in the A-stage state is a so-called solventless epoxy resin molding material. . Since the epoxy resin molding material is a solvent-free type, the molded product of the epoxy resin molding material can be obtained without going through a drying step, and the steps for obtaining the molded product or the molded hardened product of the present embodiment can be simplified.

<Molded and hardened products>

The molded article of the present embodiment is produced by press-forming the epoxy resin molding material of the present embodiment.

As a method of press-forming the epoxy resin molding material of the present embodiment, the transfer molding method is the most general method. In this embodiment, a compression molding method or the like can also be used. After molding the epoxy resin molding material of this embodiment, the molded product peeled off from the mold can be used as it is, but it can also be heated by an oven or the like as needed to perform post-hardening before use.

The molded hardened product of the present embodiment is a product that is post-hardened by heating the molded product of the present embodiment.

The heating conditions of the molded product can be appropriately selected according to the types and amounts of the epoxy resin, phenolic hardener, and the like contained in the epoxy resin molding material. For example, the heating temperature of the molded product is preferably 130 to 200°C, more preferably 150 to 180°C. For example, the heating time of the molded product is preferably 1 to 10 hours, and more preferably 2 to 6 hours.

The epoxy resin molding material of the present embodiment can be used in fields such as printed wiring boards, sealing materials for semiconductor elements, etc., in addition to motors and inverters for industrial and automobile use.

[Example]

Next, the present invention will be specifically explained by examples, but the present invention is not limited to these examples.

The following components were added according to the mass parts shown in Tables 1 to 5 below, and roller kneading was performed under the conditions of a kneading temperature of 80° C. and a kneading time of 10 minutes to produce Examples 1 to 10 and Comparative Examples 1 to 10. Epoxy molding material. In addition, "-" in the table means no addition.

In any of Examples 1 to 10 and Comparative Examples 1 to 10, the epoxy resin molding materials are in the A state.

In addition, after the epoxy resin molding materials of Examples 1 to 10 and Comparative Examples 1 to 10 were heated at 180° C. for 1 hour, the mass reduction rate was 0.1% by mass or less.

Hereinafter, the raw materials used for preparing the epoxy resin molding material and their abbreviations are shown.

[Epoxy resin]

<Epoxy resin 1>

YL6121H (manufactured by Mitsubishi Chemical Corporation, the compound of R=H and R=CH ₃ in the following formula is about 1:1 mixture, epoxy equivalent is 172g/eg).

<Epoxy resin 2>

1-(3-methyl-4-epoxyethylmethoxyphenyl)-4-(4-epoxyethylmethoxyphenyl)-cyclohexene (please refer to Japanese Patent No. 4619770, Epoxy equivalent is 201g/eg).

<Epoxy resin 3>

YSLV-80XY (bisphenol F type epoxy resin, manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., epoxy equivalent is 195g/eg).

[Phenolic Hardener]

CRN (catechol resorcinol novolak (addition ratio on a mass basis is 5/95) resin.

(CRN synthesis method)

In a 3-liter branched flask equipped with a stirrer, cooler and thermometer, put 627g of resorcinol, 33g of catechol, 316.2g of 37% by mass formaldehyde solution, 15g of oxalic acid, and 300g of water, with the oil bath side Increase the temperature to 100°C while heating. Reflux at about 104°C and maintain the reflux temperature for 4 hours. Thereafter, while the water was fractionally distilled, the temperature in the flask was increased to 170°C and kept at 170°C for 8 hours. After the reaction, concentration was carried out under reduced pressure for 20 minutes, and water and the like in the system were removed to obtain a target phenol resin (CRN).

Furthermore, the structure of the obtained CRN was confirmed by FD-MS. At this time, it was confirmed that all of the partial structures represented by the general formulas (II-1) to (II-4) above exist.

In addition, among the above reaction conditions, a compound having a partial structure represented by the above general formula (II-1) will be generated at the earliest, and by dehydration reaction of this compound, it is considered that a compound having the above general formula (II-2) can be generated ) ~ (II-4) at least one part of the structure of the compound represented.

Regarding the obtained CRN, the measurement of Mn and Mw was performed in the following manner.

The measurement of Mn and Mw was performed using a high-performance liquid chromatograph L6000 (model) manufactured by Hitachi, Ltd., and a data analysis device C-R4A (model) manufactured by Shimadzu Corporation. For the GPC column for analysis, G2000HXL and G3000HXL (model) manufactured by TOSOH Corporation were used. The sample concentration was set to 0.2% by mass, tetrahydrofuran was used as the mobile phase, and the flow rate was set to 1.0 mL/min. A polystyrene standard was used to prepare a standard curve, and the standard curve was used to calculate Mn and Mw in terms of polystyrene conversion values.

Regarding the obtained CRN, the measurement of the hydroxyl equivalent was carried out in the following manner.

Hydroxyl equivalent is measured by acetyl chloride-potassium hydroxide titration. In addition, the method of judging the end point of the titration, because the color of the solution is dark, is not performed by the coloring method using the indicator, but by the potential titration method. Specifically, in this method, the hydroxyl group of the resin to be measured is acetylated in a pyridine solution, and the excess reagent is decomposed with water to produce acetic acid, and then the acetic acid is titrated with a potassium hydroxide/methanol solution. .

The obtained CRN is a mixture of compounds having a partial structure represented by at least one of the general formulas (II-1) to (II-4), and Ar is derived from 1,2-dihydroxybenzene (catechol) ) And a group derived from 1,3-benzenediol (resorcinol), wherein R ¹¹ of the above general formula (II-a) is a hydroxyl group, R ¹² and R ¹³ are hydrogen atoms, and CRN is A phenol resin containing a hardener (hydroxyl equivalent 62g/eq, number average molecular weight 422, weight average molecular weight 564) as a low-molecular diluent, and the hardener contains 35% by mass of a monomer component (resorcinol).

[Insulating inorganic filler]

PYROKISUMA 3350 (magnesium oxide, manufactured by Kyowa Chemical Industry Co., Ltd., average particle diameter 50 μm, specific surface area 0.1 m ² /g).

PYROKISUMA 3320 (magnesium oxide, manufactured by Kyowa Chemical Industry Co., Ltd., average particle diameter 20 μm, specific surface area 0.2 m ² /g).

STARMAG SL (magnesium oxide, manufactured by Shendao Chemical Industry Co., Ltd., average particle diameter 8 μm, specific surface area 1 m ² /g).

AL35-63 (alumina, manufactured by Micron Co., Ltd., with an average particle diameter of 50 μm and a specific surface area of 0.1 m ² /g).

AL35-45 (alumina, manufactured by Micron Co., Ltd., with an average particle diameter of 20 μm and a specific surface area of 0.2 m ² /g).

AX3-32 (alumina, manufactured by Micron Co., Ltd., average particle diameter 4 μm, specific surface area 1 m ² /g).

[Silane coupling agent]

KBM-202SS (diphenyldimethoxysilane, manufactured by Shin-Etsu Chemical Industry Co., Ltd., molecular weight 244).

KBM-573 (3-phenylaminopropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Industry Co., Ltd., molecular weight 255).

KBM-403 (3-glycidoxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd., molecular weight 236).

[Hardening accelerator]

TPP (triphenylphosphine, manufactured by Beixing Chemical Co., Ltd.).

[Release agent]

Octanoic acid ester (Licowax E, manufactured by Clariant Japan Co., Ltd.).

<Measurement of forming and thermal conductivity>

The epoxy resin molding materials of Examples 1 to 10 and Comparative Examples 1 to 10 were transferred into a molding machine with a molding pressure of 20 MP at 180°C for 300 seconds or at 130°C for 900 seconds. Under conditions. When post-curing is performed, the curing conditions are set at 180°C for 5 hours. In addition, the "formability" in Tables 1 to 5 means that the epoxy resin molding material is in a flowing state and can be filled in the mold, and it is judged as "possible", and the unfilled part in the mold is judged as "no".

The obtained epoxy resin molded product or its post-cured product (formed cured product) was cut into 10 mm squares and blackened with graphite spray, followed by xenon flash method (using LFA447nanoflash (model) made by NETZSCH) Evaluate the thermal diffusivity. The thermal conductivity of the epoxy resin molded product or its post-cured product is obtained from the product of the thermal diffusivity value, density, and specific heat, where the density is determined by the Archimedes method, The specific heat is measured by DSC (using Pyris1 (model) manufactured by Perkin Elmer Co., Ltd. The results are described in Tables 1 to 5. In the table, those who are judged to be "No" in "Possibility of forming" because The thermal conductivity cannot be evaluated, so it is indicated by "-".

The same components in Examples 1 to 5 and Comparative Examples 1 to 5 are epoxy resin 1 and magnesium oxide 72 vol%, and the same components in Example 6 and Comparative Example 6 are epoxy resin 2 and magnesium oxide 70 vol%, Example 7 and Comparative Example 7 The same components in epoxy resin 1 and magnesium oxide are 78% by volume, and the same components in examples 8-9 and comparative examples 8-9 are epoxy resin 1 and alumina 76% by volume. Moreover, the ratio with respect to the epoxy resin 1 of Example 10 is 50 mass% of the whole epoxy resin, and the comparative example 10 is 0% (all are the epoxy resin 3).

Initially, Comparative Examples 6 to 8 having a composition different from that of this embodiment form cannot be formed. Secondly, among the moldable materials, Examples 1 to 9 containing a silane coupling agent KBM-202SS or KBM-573 having a phenyl group are compared with Comparative Example 1 and Comparative Example 2 which have different compositions from this embodiment. ~5 and Comparative Example 9, the thermal conductivity of Examples 1-9 increased by 1W/(m.K)~2W/(m.K), where Comparative Example 1 does not contain a silane coupling agent, Comparative Examples 2~5 and Comparative Example 9 contains KBM-403, which is a silane coupling agent that does not contain a phenyl group.

In addition, the thermal conductivity of Example 10 is increased by more than 1 W/(m·K) compared to Comparative Example 10, which has a different composition from this embodiment. Among them, in Example 10, an epoxy resin having a liquid crystal-based skeleton The ratio is 50% by mass of the entire epoxy resin, and Comparative Example 10 does not contain an epoxy resin having a liquid crystal matrix.

This specification is based on the disclosure content of Japanese Patent Application No. 2014-253355 filed on December 15, 2014, and is incorporated into this specification by reference.

All documents, patent applications, and technical specifications described in this specification are incorporated into this specification by reference to individual documents, patent applications, and technical specifications, and when specifically and individually described, they are also borrowed It is incorporated into this manual by reference.

Claims (9)

An epoxy resin molding material containing an epoxy resin, a phenolic hardener, an insulating inorganic filler, and a silane coupling agent; the silane coupling agent includes a silane coupling agent having a phenyl group; the silane coupling agent having a phenyl group Contains a silane coupling agent in which a phenyl group is directly bonded to a silicon atom; the ratio of the silane coupling agent having a phenyl group in the silane coupling agent is more than 90% by mass; the phenyl group is directly bonded to a silicon atom The ratio of the silane coupling agent in the silane coupling agent having a phenyl group is 80% by mass or more; the epoxy resin includes an epoxy resin having a liquid crystal matrix; the ratio of the epoxy resin having a liquid crystal matrix , The whole of the epoxy resin is 50% by mass or more; the phenol-based hardener contains the following compound selected from the following general formula (II-1) to the following general formula (II-4) At least one compound of the structure represented in the group:

In the general formula (II-1) to the general formula (II-4), m and n are each independently a positive integer and represent the number of respective structural units; and Ar represents the following general formula (II-a) And the radical represented by any of (II-b):

In the general formulae (II-a) and (II-b), R ¹¹ and R ¹⁴ each independently represent a hydrogen atom or a hydroxyl group; R ¹² and R ¹³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms . The epoxy resin molding material according to claim 1, wherein the epoxy resin molding material is in the A-stage state. The epoxy resin molding material according to claim 2, wherein the mass reduction rate after heating at 180°C for 1 hour is 0.1% by mass or less. The epoxy resin molding material according to any one of claims 1 to 3, wherein the coating amount of silicon atoms derived from the silane coupling agent is 5.0×10 ⁻ per unit specific surface area of the insulating inorganic filler ^{. 6} mol/m ² ~10.0×10 ^-6 mol/m ² . The epoxy resin molding material according to any one of claims 1 to 3, wherein the insulating inorganic filler includes at least one selected from the group consisting of magnesium oxide and aluminum oxide. The epoxy resin molding material according to any one of claims 1 to 3, wherein the content of the insulating inorganic filler is 60% by volume to 90% by volume in the solid content. The epoxy resin molding material according to any one of claims 1 to 3, wherein the ratio of the epoxy resin having a liquid crystal matrix is 90% by mass or more in the entire epoxy resin. A molded product is produced by press-forming the epoxy resin molding material according to any one of claims 1 to 7. A shaped hardened product obtained by heating the shaped product described in claim 8 and post-hardening it.