WO2021166541A1

WO2021166541A1 - Heat conductive material forming composition, heat conductive sheet, heat conductive multilayer sheet, and device having heat conductive sheet

Info

Publication number: WO2021166541A1
Application number: PCT/JP2021/002045
Authority: WO
Inventors: 林　大介; 誠一人見; 輝樹新居; 慶太高橋; 信小澤
Original assignee: 富士フイルム株式会社
Priority date: 2020-02-19
Filing date: 2021-01-21
Publication date: 2021-08-26
Also published as: JPWO2021166541A1; JP7245953B2

Abstract

The present invention addresses the problem of providing a composition for forming a heat conductive material having excellent heat conductivity. Also, the present invention addresses the problem of providing a heat conductive sheet, a heat conductive multilayer sheet, and a device having a heat conductive sheet, which are formed of said composition. A heat conductive material forming composition according to the present invention contains inorganic particles and a compound represented by general formula (1).

Description

Compositions for forming heat conductive materials, heat conductive sheets, heat conductive multilayer sheets, and devices with heat conductive layers

The present invention relates to a composition for forming a heat conductive material, a heat conductive sheet, a heat conductive multilayer sheet, and a device with a heat conductive layer.

Power semiconductor devices used in various electric devices such as personal computers, general household appliances, and automobiles have been rapidly miniaturized in recent years. With the miniaturization, it becomes difficult to control the heat generated from the high-density power semiconductor device.
In order to deal with such a problem, a heat conductive material that promotes heat dissipation from the power semiconductor device is used.
For example, Patent Document 1 describes a heat conductive material containing a compound represented by the following general formula (XII) as a heat conductive material used for a heat radiating sheet ([Claim 1] [Claim 8]. ] [Claim 19] [Claim 20])

International Publication No. 2017/131007

Regarding the heat conductive material described in Patent Document 1, the present inventors have set A ² , A ³ and A ⁴ in the general formula (XII) to −N = respectively, and examined a compound having a triazine ring. , It was found that there is room for improvement in thermal conductivity.

Therefore, an object of the present invention is to provide a composition for forming a heat conductive material having excellent heat conductivity.
Another object of the present invention is to provide a heat conductive sheet, a heat conductive multilayer sheet, and a device with a heat conductive layer formed by the above composition.

The present inventors have found that the thermal conductivity of the heat-conducting material to be formed is improved by using a composition for forming a heat-conducting material containing a compound having two or more triazine rings, and complete the present invention. I let you.
That is, it was found that the above-mentioned problems can be achieved by the following configuration.

[1] A composition for forming a heat conductive material, which comprises inorganic particles and a compound represented by the general formula (1).

In the above general formula (1),
E ¹ to E ⁶ independently represent a single bond, -NH-, or -NR-. R represents a substituent.
B ¹ , B ² , B ³ and B ⁴ represent k + 1 valent, l + 1 valent, m + 1 valent and n + 1 valent organic groups, respectively, and at least one of them may have a substituent k + 1. Represents a valent, l + 1 valent, m + 1 valent, or n + 1 valent aromatic ring group.
L represents a divalent organic group.
k, l, m, and n each independently represent an integer of 0 or more.
when k is 2 or more, X ¹ to the k present, may each be the same or different.
when l is 2 or more, X ² of the l present, may each be the same or different.
when m is 2 or more, X ³ and m pieces present, may each be the same or different.
when n is 2 or more, X ⁴ n number present, may each be the same or different.
Further, the total of k, l, m, and n is 2 or more.
Each of X ¹ to X ⁴ independently represents a group represented by the general formula (2).

In the above general formula (2), * represents a coupling position.
D ¹ represents a single bond or a divalent linking group.
A ¹ represents an aromatic ring group which may have a substituent or an aliphatic ring group which may have a substituent.
Q and Y ¹ are independently selected from the group consisting of a monovalent group having a hydroxyl group and an epoxy group, an amino group, a thiol group, a carboxylic acid group, an isocyanate group, and a monovalent group having an oxetanyl group. Represents a specific functional group.
p represents an integer greater than or equal to 0.
q represents an integer of 0 to 2.
In the general formula (2), if D ¹ there are a plurality, D ¹ there are a plurality, may each be the same or different. If the A ¹ there are plural, A ¹ there are a plurality, they may each be the same or different. When there are a plurality of Qs, the plurality of Qs may be the same or different.
r is an integer of 1 or more.
[2] L in the above general formula (1) is a divalent aromatic ring group which may have a substituent, a divalent aliphatic ring group which may have a substituent, and carbon. The composition for forming a heat conductive material according to [1], which is a divalent organic group having at least one selected from the group consisting of alkylene groups which may have several or more branches.
[3] The heat according to [1] or [2], wherein L in the general formula (1) is a divalent organic group having a divalent aromatic ring group which may have a substituent. Composition for forming a conductive material.
[4] The composition for forming a heat conductive material according to any one of [1] to [3], wherein the Hansen solubility parameter value of the compound represented by the general formula (1) is 28 MPa ^{0.5 or less.}
[5] The composition for forming a heat conductive material according to any one of [1] to [4], wherein the Hansen solubility parameter value of the compound represented by the general formula (1) is 26 MPa ^{0.5 or less.}
[6] The composition for forming a heat conductive material according to any one of [1] to [5], further containing a curing accelerator.
[7] The composition for forming a heat conductive material according to any one of [1] to [6], wherein the inorganic particles are inorganic nitrides.
[8] The composition for forming a heat conductive material according to any one of [1] to [7], wherein the inorganic particles are boron nitride.
[9] Of [1] to [8], the content of the compound represented by the general formula (1) is 3 to 40% by mass with respect to the total solid content of the composition for forming a heat conductive material. The composition for forming a heat conductive material according to any one.
[10] A heat conductive sheet formed by curing the composition for forming a heat conductive material according to any one of [1] to [9].
[11] The heat conductive sheet according to [10] and
A heat conductive multilayer sheet having an adhesive layer or an adhesive layer provided on one side or both sides of the heat conductive sheet.
[12] With the device
A device with a heat conductive layer, comprising a heat conductive sheet according to [10] or a heat conductive layer including the heat conductive multilayer sheet according to [11], which is arranged on the device.

According to the present invention, it is possible to provide a composition for forming a heat conductive material having excellent heat conductivity.
Further, according to the present invention, it is possible to provide a heat conductive sheet, a heat conductive multilayer sheet, and a device with a heat conductive layer formed by the above composition.

Hereinafter, the composition for forming a heat conductive material, the heat conductive sheet, the heat conductive multilayer sheet, and the device with the heat conductive layer of the present invention will be described in detail.
The description of the constituent elements described below may be based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment.
In the present specification, the numerical range represented by using "-" means a range including the numerical values before and after "-" as the lower limit value and the upper limit value.
Further, in the present specification, the epoxy group is a functional group also called an oxylanyl group. For example, two adjacent carbon atoms of a saturated hydrocarbon ring group are bonded by an oxo group (—O—) to form an oxylan ring. Epoxide groups include the groups that are used. The epoxy group may or may not have a substituent (such as a methyl group), if possible.

In the present specification, the acid anhydride group may be a monovalent group or a divalent group unless otherwise specified. When the acid anhydride group represents a monovalent group, a substitution obtained by removing an arbitrary hydrogen atom from an acid anhydride such as maleic anhydride, phthalic anhydride, pyromellitic anhydride, and trimellitic anhydride. The group is mentioned. When the acid anhydride group represents a divalent group, the group represented by * -CO-O-CO- * is intended (* represents a bond position).

In the present specification, for substituents and the like for which substitution or non-substitution is not specified, if possible, a substituent (for example, a substituent group described later) may be further added to the group as long as the desired effect is not impaired. Y) may be possessed. For example, the notation "alkyl group" means a substituted or unsubstituted alkyl group as long as the desired effect is not impaired.
In this specification, expressions such as "may" and "may" satisfy the conditions of "may" and "may". It is intended that it does not have to be satisfied. For example, "may have a substituent" also includes "may not have a substituent".
Further, in the present specification, the type of the substituent, the position of the substituent, and the number of the substituents in the case of "may have a substituent" are not particularly limited. The number of substituents may be, for example, one or two or more. Examples of the substituent include a monovalent non-metal atomic group excluding a hydrogen atom, and for example, it can be selected from the following substituent group Y.
In the present specification, examples of the halogen atom include a chlorine atom, a fluorine atom, a bromine atom, and an iodine atom.

Substituent group Y:
Halogen atom (-F, -Br, -Cl, -I, etc.), hydroxyl group, amino group, carboxylic acid group and its conjugate base group, carboxylic acid anhydride group, cyanate ester group, unsaturated polymerizable group, epoxy group, oxetanyl Group, aziridinyl group, thiol group, isocyanate group, thioisocyanate group, aldehyde group, alkoxy group, allyloxy group, alkylthio group, arylthio group, alkyldithio group, aryldithio group, N-alkylamino group, N, N-dialkylamino Group, N-arylamino group, N, N-diarylamino group, N-alkyl-N-arylamino group, acyloxy group, carbamoyloxy group, N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N, N -Dialkylcarbamoyloxy group, N, N-diarylcarbamoyloxy group, N-alkyl-N-arylcarbamoyloxy group, alkylsulfoxy group, arylsulfoxy group, acylthio group, acylamino group, N-alkylacylamino group, N -Arylacylacylamino group, carboxylicyl group, N'-alkylureid group, N', N'-dialkylureido group, N'-arylureido group, N', N'-diarylureido group, N'-alkyl-N' -Arylureide group, N-alkylureido group, N-arylureido group, N'-alkyl-N-alkylureido group, N'-alkyl-N-arylureido group, N', N'-dialkyl-N-alkyl Carbonyl group, N', N'-dialkyl-N-aryl carboxylic group, N'-aryl-N-alkyl carboxylic group, N'-aryl-N-aryl carbyl group, N', N'-diaryl-N-alkyl Carbonyl groups, N', N'-diaryl-N-aryl walide groups, N'-alkyl-N'-aryl-N-alkyl walide groups, N'-alkyl-N'-aryl-N-aryl ureido groups, alkoxy Carbonylamino Group, Allyloxycarbonylamino Group, N-alkyl-N-alkoxycarbonylamino Group, N-alkyl-N-Allyloxycarbonylamino Group, N-aryl-N-alkoxycarbonylamino Group, N-aryl-N- Allyloxycarbonylamino group, formyl group, acyl group, alkoxycarbonyl group, allyloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N, N-diaryl Carbamoyl group, N- alkyl -N- arylcarbamoyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, a sulfo group (-SO 3 _H) and its conjugated base group, alkoxy sulfonyl group, aryloxy sulfonyl Group, sulfinamoyl group, N-alkylsulfinamoyl group, N, N-dialkylsulfinamoyl group, N-arylsulfinamoyl group, N, N-diarylsulfinamoyl group, N-alkyl-N-arylsulfina Moil group, sulfamoyl group, N-alkyl sulfamoyl group, N, N-dialkyl sulfamoyl group, N-aryl sulfamoyl group, N, N-diaryl sulfamoyl group, N-alkyl-N-arylsul Famoyl group, N-acylsulfamoyl group and its conjugate base group, N-alkylsulfonylsulfamoyl group (-SO ₂ NHSO ₂ (alkyl)) and its conjugate base group, N-arylsulfonylsulfamoyl group ( -SO ₂ NHSO ₂ (aryl)) and its conjugate base group, N-alkylsulfonylcarbamoyl group (-CONHSO ₂ (alkyl)) and its conjugate base group, N-arylsulfonylcarbamoyl group (-CONHSO ₂ (aryl)) and Its conjugated base group, alkoxysilyl group (-Si (Oalkyl) ₃ ), aryloxysilyl group (-Si (Oaryl) ₃ ), hydroxysilyl group (-Si (OH) ₃ ) and its conjugated base group, phosphono group ( -PO ₃ H ₂ ) and its conjugate base group, dialkylphosphono group (-PO ₃ (alkyl) ₂ ), diarylphosphono group (-PO ₃ (aryl) ₂ ), alkylarylphosphono group (-PO ₃ (-PO 3) Alkyl)), monoalkylphosphono group (-PO ₃ H (alkyl)) and its conjugate base group, monoarylphosphono group (-PO ₃ H (aryl)) and its conjugate base group, phosphonooxy group (alkyl)) -OPO ₃ H ₂ ) and its conjugate base group, dialkylphosphonooxy group (-OPO ₃ (alkyl) ₂ ), diarylphosphonooxy group (-OPO ₃ (aryl) ₂ ), alkylarylphosphonooxy group (-. _{OPO 3 (alkyl) (aryl)} ), monoalkyl phosphono group _(-OPO 3 H _(alkyl)) and its conjugated base group, monoaryl phosphonate Nookishi group _(-OPO 3 H _(aryl)) and its conjugated base group, a cyano group, a nitro group, an aryl group, an alkenyl group, an alkynyl group and an alkyl group.
Further, these substituents may or may not form a ring by combining the substituents with each other or with the substitutable group, if possible.
Further, in the present specification, as each component, a substance corresponding to each component may be used alone or in combination of two or more. Here, when two or more kinds of substances are used in combination for each component, the content of the component means the total content of the substances used in combination unless otherwise specified.

[Composition for forming a heat conductive material]
The composition for forming a heat conductive material of the present invention (hereinafter, also abbreviated as “composition of the present invention”) is an inorganic particle and a compound represented by the general formula (1) described later (hereinafter, also abbreviated as “specific compound”). .) Including.

The composition for forming a heat conductive material of the present invention having such a structure can form a heat conductive material having excellent heat conductivity.
This is not clear in detail, but the present inventors speculate as follows.
That is, since the specific compound is a compound having two or more triazine rings, it is considered that the specific compound has a high affinity with inorganic particles.
Further, since the specific compound has at least two predetermined groups (specific functional groups), not only between the inorganic particles having a high affinity but also between the specific compounds, the specific compound and the specific compound as desired. It is considered that an interaction occurs with other components to be added (for example, a phenol compound and / or an epoxy compound).
Therefore, the heat conduction path through the specific compound is formed by the interaction of the specific compound via the specific functional group, so that the heat conductivity of the heat conductive material formed by using the composition of the present invention is improved. The inventors speculate that this is the case.

Hereinafter, the components contained in the composition will be described in detail.

[Specific compound]
The composition for forming a heat conductive material of the present invention contains a specific compound.
The specific compound is a compound represented by the general formula (1).

In the general formula (1), E ¹ to E ⁶ independently represent a single bond, -NH-, or -NR-.
R represents a substituent. Examples of the substituent represented by R include a linear or branched alkyl group having 1 to 5 carbon atoms. When a ^{plurality of -NR- are present in E 1} to E ⁶ , the plurality of Rs may be the same or different.
Among them, in the general formula (1), from the viewpoint of thermal conductivity of the resulting thermally conductive material is more ^excellent, E 1 ~ ^{E 6} are each independently, -NH-, or, -NR- is preferably, -NH- Is more preferable.

In the general formula (1), B ¹ , B ² , B ³ and B ⁴ represent k + 1 valent, l + 1 valent, m + 1 valent and n + 1 valent organic groups, respectively, and at least one of them comprises a substituent. It represents a k + 1 valent, l + 1 valent, m + 1 valent, or n + 1 valent aromatic ring group that may have.

Examples of the organic group represented by B ¹ to B ⁴ include a group obtained by removing j hydrogen atoms from a hydrocarbon group which may have a hetero atom having 1 to 20 carbon atoms. In addition, j means k + 1, l + 1, m + 1, or n + 1.
Here, the hydrocarbon group before removing j hydrogen atoms may have, for example, an aliphatic hydrocarbon group having 1 to 20 carbon atoms and a substituent which may have a substituent. Examples thereof include an aliphatic ring group having 3 to 20 carbon atoms and an aromatic ring group having 3 to 20 carbon atoms which may have a substituent.
Examples of the aliphatic hydrocarbon group having 1 to 20 carbon atoms include methane, ethane, propane, butane, pentane, hexane, and heptane.
Examples of the aliphatic ring group having 3 to 20 carbon atoms include a cyclohexane ring group, a cycloheptane ring group, a norbornane ring group, and an adamantane ring group.
Examples of the aromatic ring group having 3 to 20 carbon atoms include an aromatic hydrocarbon group having 6 to 20 carbon atoms and an aromatic heterocyclic group having 3 to 20 carbon atoms.
Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms include a benzene ring, a naphthalene ring and an anthracene ring, and examples of the aromatic heterocyclic group having 3 to 20 carbon atoms include a furan ring and a pyrrole ring. , Thiophene ring, pyridine ring, thiazole ring, carbazole ring, indole ring, benzothiazole ring and the like.

Of these, ^{as the organic group represented by B 1} to B ^4, j hydrogen atoms were removed from the aromatic ring group which may have a substituent because the heat conductivity of the heat conductive material is more excellent. It is preferably a group, and more preferably a group obtained by removing j hydrogen atoms from the benzene ring.

In the general formula (1), k, l, m, and n each independently represent an integer of 0 or more. However, the total of k, l, m, and n is 2 or more.
For l, m, and n, 0 to 5 is preferable, and 1 to 2 is more preferable, respectively.
When k is 0, B ¹ does not have X ^1. When l is 0, B ² does not have X ^2. If m is 0, then B ³ does not have X ^3. If n is 0, then B ⁴ does not have X ^4.

when k is 2 or more (that is, if X ¹ there are a plurality), X ¹ present a plurality (k number) may each be the same or different. when l is 2 or more (that is, if X ² there are a plurality), X ² that there are a plurality of (l number) may each be the same or different. when m is 2 or more (that is, if X ³ there are a plurality), X ³ present a plurality (m pieces) may each be the same or different. when n is 2 or more (that is, if X ⁴ there are a plurality), X ⁴ present more of (n) may each be the same or different.

In the general formula (1), the total number of k, l, m, and n is 2 or more, preferably an integer of 2 to 12, and more preferably an integer of 4 to 8.
^{In other words, the total number of X 1} to X ⁴ which may exist in a plurality of each is 2 or more, preferably an integer of 2 to 12, and more preferably an integer of 4 to 8.

For example, k is preferably 1 or more (more preferably 1 to 2), l is preferably 1 or more (more preferably 1 to 2), and m is 1 or more (more preferably 1 to 2). It is preferable that n is 1 or more (more preferably 1 to 2).
That is, B ¹ preferably has 1 or more (preferably 1 to 2) X ¹ ^{and B 2} preferably has 1 or more (preferably 1 to 2) X ^2. ³ preferably has one or more (preferably one or two) X ^3.

L represents a divalent organic group.
Examples of the organic group include an aromatic ring group which may have a substituent, an aliphatic hydrocarbon group which may have a substituent, an aliphatic ring group which may have a substituent, and-. Examples thereof include O-, -S-, -N ( ^RN )-or -C (= O)-, or a group in which these are combined.
R ^N represents a substituent. The substituents represented by R ^N, e.g., like a linear or branched alkyl group having 1 to 5 carbon atoms.
Further, examples of the aromatic ring group, the aliphatic hydrocarbon group, and the substituent that the aliphatic ring group may have include a linear or branched alkyl group having 1 to 5 carbon atoms. Can be mentioned.

Examples of the aromatic ring group include an aromatic hydrocarbon group having 6 to 20 carbon atoms and an aromatic heterocyclic group having 3 to 20 carbon atoms.
Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms include a monocyclic aromatic ring group such as a benzene ring; a polycyclic aromatic ring group such as a naphthalene ring and an anthracene ring; and the like. Examples of the 3 to 20 aromatic heterocyclic groups include monocyclic aromatic ring groups such as a furan ring, a pyrrole ring, a thiophene ring, a pyridine ring, and a thiazole ring; a benzothiazole ring, a carbazole ring, and an indole ring. Polycyclic aromatic ring groups such as;
Examples of the aromatic ring group as L include a group obtained by removing two hydrogen atoms from the above example.

Examples of the aliphatic hydrocarbon group include an alkylene group having 1 to 12 carbon atoms, and specifically, a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group and a methylhexylene group. , And a heptylene group and the like.

Examples of the aliphatic ring group include a cyclohexane ring group, a cycloheptane ring group, a norbornane ring group, and an adamantane ring group.
As the aliphatic ring group as L, a group obtained by removing two hydrogen atoms from the above example can be mentioned.

Aromatic ring group which may have a substituent, an aliphatic hydrocarbon group which may have a substituent, an aliphatic ring group which may have a substituent, or -O-, -S. The group in which -, -N ( ^RN )-or -C (= O)-is combined is not only a divalent linking group consisting of two or more of these, but also a group of the same type (for example, an aromatic ring). It may be a divalent linking group in which two or more groups) are combined via a single bond.

In the present invention, it is preferable that both ends of L are carbon atoms from the viewpoint that the heat conductive material is more excellent in heat conductivity. The terminal carbon atom may be a part of the cyclic structure.
Further, in the present invention, from the viewpoint that the thermal conductivity of the heat conductive material is more excellent, L in the above general formula (1) may have a divalent aromatic ring group or a substituent which may have a substituent. It is a divalent organic group having at least one selected from the group consisting of a divalent aliphatic ring group which may have and an alkylene group which may have a branch having 2 or more carbon atoms. It is preferable, and a divalent organic group having a divalent aromatic ring group which may have a substituent may be more preferable because the thermal conductivity is more excellent.

In the general formula (1), r is an integer of 1 or more.
r is preferably an integer of 1 to 20, and more preferably an integer of 1 to 10.

In the general formula (1), X ¹ to X ⁴ independently represent the groups represented by the general formula (2).

In the above general formula (2), * represents a bonding position with any of ^{B 1} to B ^4.

In the above general formula (2), D ¹ represents a single bond or a divalent linking group.
Examples of the divalent linking group include -O-, -S-, -CO-, -NR ^N- , -SO _2- , an alkylene group, or a group composed of a combination thereof. -NR ^N - in ^{R N} represents a hydrogen atom or a substituent. The alkylene group is preferably a linear or branched alkylene group having 1 to 8 carbon atoms.
Among them, D ¹ is preferably "single bond" or "a group consisting of a combination selected from the group consisting of -O-, -CO-, and an alkylene group", and is preferably a single bond, * ^A -alkylene group-O-. CO- * ^B , * ^A- CO-O-alkylene group-* ^B , * ^A- O-alkylene group-O- * ^B , * ^A- CO-O-alkylene group-O-CO- * ^B , * ^A -CO-O-alkylene group-O- * ^B or * ^A- O-alkylene group-O-CO- * ^B is more preferable.
* ^A represents a a bond position opposite to the ^{A 1,} ^{* B} is the bonding position to ^{A 1.}

In the above general formula (2), A ¹ represents an aromatic ring group which may have a substituent or an aliphatic ring group which may have a substituent.
In addition, A ¹ is ^{bonded to D 1} , Y ¹ , and Q with an atom constituting the aromatic ring group or the aliphatic ring group.

Which is one embodiment of the A ^1, good aromatic ring which may have a substituent group may be either a monocyclic aromatic ring group polycyclic aromatic ring group.
The number of membered rings of the monocyclic aromatic ring group is preferably 6 to 10.
The number of rings constituting the polycyclic aromatic ring group is preferably 2 to 4, more preferably 2. The number of membered rings of the rings constituting the polycyclic aromatic ring group is preferably 5 to 10 independently.
The aromatic ring group may be an aromatic hydrocarbon ring group or an aromatic heterocyclic group.
The number of heteroatoms contained in the aromatic heterocyclic group is preferably 1 to 5. Examples of the hetero atom include a nitrogen atom, a sulfur atom, an oxygen atom, a selenium atom, a tellurium atom, a phosphorus atom, a silicon atom, and a boron atom. Of these, a nitrogen atom, a sulfur atom, or an oxygen atom is preferable.
Examples of the aromatic ring group include a benzene ring group, a naphthalene ring group, an anthracene ring group, a benzothiazole ring group, a carbazole ring group, an indole ring group and the like.

Which is one embodiment of the A ^1, an aliphatic ring group which may have a substituent, may be monocyclic or polycyclic.
The number of membered rings of the monocyclic aliphatic ring group is preferably 6 to 10.
The number of rings constituting the polycyclic aliphatic ring group is preferably 2 to 4, more preferably 2. The number of membered rings of the rings constituting the polycyclic cycloalkane ring group is preferably 5 to 10 independently.
The number of carbon atoms as ring member atoms in the aliphatic ring group is preferably 6 or more, more preferably 6 to 12. The number of carbon atoms which are ring-membered atoms is intended to be the number of carbon atoms which are ring-membered atoms constituting the aliphatic ring.
Examples of the aliphatic ring group include a cyclohexane ring group, a cycloheptane ring group, a norbornane ring group, and an adamantane ring group.

In the above general formula (2), Q and Y ¹ are independently a hydroxyl group (-OH), a monovalent group having an epoxy group, an amino group, a thiol group (-SH), and a carboxylic acid group (-COOH). Represents a specific functional group selected from the group consisting of a monovalent group having an isocyanate group (-NCO) and an oxetanyl group.
That is, the group represented by the general formula (2) is a group having at least one specific functional group. Here, the group represented by the general formula (2) is "a group having a specific functional group" even if the group represented by the general formula (2) is a group containing a specific functional group as a part. Often, the group represented by the general formula (2) may be the specific functional group itself.

As the monovalent group having an epoxy group as the specific functional group, for example, ^{a group represented by "-Leo} -epoxy group" is preferable. ^Leo is a single bond or divalent linking group, and an oxygen atom, an alkylene group (preferably a linear or branched alkylene group having 1 to 6 carbon atoms), or a group composed of a combination thereof. preferable.
Among them, the monovalent group having the epoxy group is preferably "-O-alkylene group-epoxy group".
As the substituent that the epoxy group may have, a linear or branched alkyl group having 1 to 6 carbon atoms is preferable.

The amino group as the specific functional group is not particularly limited, and may be any of primary, secondary, and tertiary. For example, -N ( ^RE ) ₂ ( ^RE may be a hydrogen atom or an alkyl group (which may be linear or branched) independently of each other). The number of carbon atoms in the alkyl group is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3. The alkyl group may further have a substituent.

As the specific functional group, monovalent group having an oxetanyl group is, for example, groups represented by "- ^- L ^eo oxetanyl group" are preferred. ^Leo is a single bond or divalent linking group, and an oxygen atom, an alkylene group (preferably a linear or branched alkylene group having 1 to 6 carbon atoms), or a group composed of a combination thereof. preferable.
Among them, the monovalent group having an oxetanyl group is preferably "-O-alkylene group-oxetanyl group".
As the substituent that the oxetanyl group may have, a linear or branched alkyl group having 1 to 6 carbon atoms is preferable.

Among them, the specific functional group is preferably a monovalent group having a hydroxyl group or an epoxy group.

In the above general formula (2), p represents an integer of 0 or more.
Among them, p is preferably 0 to 5, more preferably 0 to 1.
When p is 0, Y ¹ binds directly to any of B ¹ to B ^4. That is, X ¹ to X ⁴ may be the specific functional group itself.

In the above general formula (2), q represents an integer of 0 to 2.
Among them, q is preferably 0 to 1.

When a plurality of groups represented by the general formula (2) are present in the specific compound, the groups represented by the plurality of general formulas (2) may be the same or different.
For example, in the general formula (2), if D ¹ there are a plurality, D ¹ there are a plurality, they may each be the same or different. If the A ¹ there are plural, A ¹ there are a plurality, they may each be the same or different. When there are a plurality of Qs, the plurality of Qs may be the same or different.

The specific compound may have one group represented by the general formula (2) alone, or may have two or more groups.
Among them, the specific compound is preferably "a compound having only a hydroxyl group as a specific functional group" or "a compound having only a monovalent group having an epoxy group as a specific functional group".

In the present invention, the Hansen solubility parameter (hereinafter, also abbreviated as "HSP") value of the compound represented by the general formula (1) is preferably ^{28 MPa 0.5 or less because the water resistance is improved.} , 26 MPa ^0.5 or less is more preferable. The lower limit of the HSP value of the specific compound is not limited, and for example, 10 MPa ^0.5 or more is preferable.
As the HSP value of the specific compound, the value calculated from the following formula is adopted.
HSP value = (HSP _d ² + HSP _p ² + HSP _h ² ) ^0.5
HSP _d , HSP _p , and HSP _h represent the dispersion term, polarity term, and hydrogen bond term of HSP values, respectively (units are MPa ^0.5 ).
HSP _d , HSP _p , HSP _h are HSPiP (Hansen Solubility Parameter)

In the composition for forming a heat conductive material of the present invention, the content of the specific compound is preferably 3 to 40% by mass, preferably 3 to 40% by mass, based on the total solid content of the composition, from the viewpoint that the heat conductivity of the heat conductive material is more excellent. More preferably, it is ~ 25% by mass.

Further, in the composition of the present invention, the content of the specific compound is preferably 4 to 60% by mass, more preferably 10 to 35% by mass, still more preferably 12 to 30% by mass, based on the mass of the inorganic particles.
The specific compound may be used alone or in combination of two or more.

[Phenol compound]
The composition of the present invention may further contain a phenolic compound.
The phenol compound is a compound other than the specific compound. For example, even when the specific compound has a phenolic hydroxyl group, the specific compound does not correspond to the phenol compound.
The phenolic compound is selected from the group consisting of the compound represented by the general formula (P1) or the compound represented by the general formula (P2) because the obtained heat conductive material has more excellent thermal conductivity. It is preferably one or more.

<Compound represented by the general formula (P1)>
The general formula (P1) is shown below.

In the general formula (P1), m1 represents an integer of 0 or more.
m1 is preferably 0 to 10, more preferably 0 to 3, still more preferably 0 or 1, and particularly preferably 1.

In the general formula (P1), na and nc each independently represent an integer of 1 or more.
Na and nc are preferably 1 to 4 independently of each other.

In the general formula (P1), R ¹ and R ⁶ independently represent a hydrogen atom, a halogen atom, a carboxylic acid group, a boronic acid group, an aldehyde group, an alkyl group, an alkoxy group, or an alkoxycarbonyl group.
The alkyl group may be linear or branched. The alkyl group preferably has 1 to 10 carbon atoms. The alkyl group may or may not have a substituent.
The alkyl group portion of the alkoxy group and the alkyl group portion of the alkoxycarbonyl group are the same as those of the alkyl group.
Independently, R ¹ and R ⁶ are preferably a hydrogen atom or a halogen atom, more preferably a hydrogen atom or a chlorine atom, and even more preferably a hydrogen atom.

In the general formula (P1), R ⁷ represents a hydrogen atom or a hydroxyl group.
If R ⁷ there is a plurality, R ⁷ where there are a plurality, may each be the same or different.
If R ⁷ there are a plurality of R ⁷ there are a plurality, also preferably at least one R ⁷ is a hydroxyl group.

In the general formula (P1), L ^x1 represents a single bond, -C (R ² ) (R ³ )-or-CO-, and -C (R ² ) (R ³ )-or -CO- preferable.
L ^x2 represents a single bond, -C (R ⁴ ) (R ⁵ )-or-CO-, and -C (R ⁴ ) (R ⁵ )-or-CO- is preferable.
R ² ~ ^{R 5} each independently represent a hydrogen atom or a substituent.
The above-mentioned substituents are preferably a hydroxyl group, a phenyl group, a halogen atom, a carboxylic acid group, a boronic acid group, an aldehyde group, an alkyl group, an alkoxy group, or an alkoxycarbonyl group, and preferably a hydroxyl group, a halogen atom, or a carboxylic acid group. , Boronic acid group, aldehyde group, alkyl group, alkoxy group, or alkoxycarbonyl group are more preferable.
The alkyl group may be linear or branched. The alkyl group preferably has 1 to 10 carbon atoms. The alkyl group may or may not have a substituent.
The alkyl group portion of the alkoxy group and the alkyl group portion of the alkoxycarbonyl group are the same as those of the alkyl group.
The phenyl group may or may not have a substituent, and when it has a substituent, it more preferably has 1 to 3 hydroxyl groups.
Independently, R ² to R ⁵ are preferably a hydrogen atom or a hydroxyl group, and more preferably a hydrogen atom.
L ^x1 and L ^x2 are independently -CH _2- , -CH (OH)-, -CO-, or, respectively.
-CH (Ph)-is preferable.
The Ph represents a phenyl group which may have a substituent.
Incidentally, in the general formula (P1), if R ⁴ there are a plurality, R ⁴ there are a plurality may each be the same or different. If R ⁵ there are a plurality, the plurality of R ⁵ may each be the same or different.

In the general formula (P1), Ar ¹ and Ar ² independently represent a benzene ring group or a naphthalene ring group, respectively.
Ar ¹ and Ar ² are preferably benzene ring groups independently of each other.

In the general formula (P1), Q ^a is a hydrogen atom, an alkyl group, a phenyl group, a halogen atom, a carboxylic acid group, a boronic acid group, aldehyde group, alkoxy group or an alkoxycarbonyl group.
The alkyl group may be linear or branched. The alkyl group preferably has 1 to 10 carbon atoms. The alkyl group may or may not have a substituent.
The alkyl group portion of the alkoxy group and the alkyl group portion of the alkoxycarbonyl group are the same as those of the alkyl group.
The phenyl group may or may not have a substituent.
Q ^a is preferably bonded to the para position with respect to the hydroxyl group that the benzene ring group to which ^{Q a is bonded may have.}
Q ^a is preferably a hydrogen atom or an alkyl group. The alkyl group is preferably a methyl group.

^{When there are a plurality of R 7} , L ^{x 2} , and / or Q ^a in the general formula (P1), the plurality of R ⁷ , L ^{x 2} , and / or Q ^a are the same but different. May be good.

<Compound represented by the general formula (P2)>
The general formula (P2) is shown below.

In the general formula (P2), m2 represents an integer of 0 or more.
The m2 is preferably 0 to 10, more preferably 0 to 4.

In the general formula (P2), nx represents an integer of 0 to 4.
nx is preferably 1 to 2, and more preferably 2.

In the general formula (P2), ny represents an integer of 0 to 2.
When there are a plurality of ny, the ny existing may be the same or different.
Of the nys that may exist in plurality, at least one ny preferably represents 1. For example, when m2 represents 1, it is preferable that one existing ny represents 1. When m2 represents 4, it is preferable that at least one ny of four existing ny represents 1, and more preferably two ny represent 1.

In the general formula (P2), nz represents an integer of 0 to 2.
The nz is preferably 1.

In the general formula (P2), the total number of nx, ny that may exist in a plurality of ny, and nz is preferably 2 or more, and more preferably 2 to 10.

In the general formula (P2), R ¹ and R ⁶ independently represent a hydrogen atom, a halogen atom, a carboxylic acid group, a boronic acid group, an aldehyde group, an alkyl group, an alkoxy group, or an alkoxycarbonyl group.
^{R 1} and ^{R 6} in the general formula (P2) is the general formula (1) and ^{R 1} and ^{R 6} in the same respectively.
If R ¹ there are a plurality, R ¹ existing in plural numbers may each be the same or different. If R ⁶ there are a plurality, R ⁶ existing in plural numbers may each be the same or different.

In the general formula (P2), Q ^b represents a hydrogen atom, an alkyl group, a phenyl group, a halogen atom, a carboxylic acid group, a boronic acid group, an aldehyde group, an alkoxy group, or an alkoxycarbonyl group.
The alkyl group may be linear or branched. The alkyl group preferably has 1 to 10 carbon atoms. The alkyl group may or may not have a substituent.
The alkyl group portion of the alkoxy group and the alkyl group portion of the alkoxycarbonyl group are the same as those of the alkyl group.
The phenyl group may or may not have a substituent.
Q ^b is preferably a hydrogen atom.
When there are a plurality of ^{Q bs} ^{, the plurality of Q bs} may be the same or different.

Specific examples of the compound represented by the general formula (P2) include benzenetriol (preferably 1,3,5-benzenetriol).

Examples of other phenol compounds include biphenyl aralkyl type phenol resin, phenol novolac resin, cresol novolac resin, aromatic hydrocarbon formaldehyde resin modified phenol resin, dicyclopentadienephenol addition type resin, phenol aralkyl resin, and polyhydric hydroxy compound. Polyhydric phenol novolac resin synthesized from formaldehyde, naphthol aralkyl resin, trimethylol methane resin, tetraphenylol ethane resin, naphthol novolac resin, naphthol phenol co-shrink novolac resin, naphthol cresol co-shrink novolak resin, biphenyl-modified phenol resin, Biphenyl-modified naphthol resin, aminotriazine-modified phenol resin, alkoxy group-containing aromatic ring-modified novolak resin and the like are preferable.

The lower limit of the hydroxyl group content of the phenol compound is preferably 3.0 mmol / g or more, more preferably 8.0 mmol / g or more, further preferably 11.0 mmol / g or more, and particularly preferably 12.0 mmol / g or more. Most preferably 13.0 mmol / g or more. The upper limit is preferably 25.0 mmol / g or less, more preferably 23.0 mmol / g or less.
The hydroxyl group content is intended to be the number of hydroxyl groups (preferably phenolic hydroxyl groups) possessed by 1 g of the phenol compound.
In addition to the hydroxyl group, the phenol compound may or may not have an active hydrogen-containing group (carboxylic acid group or the like) capable of polymerizing with the epoxy compound. The lower limit of the active hydrogen content of the phenol compound (total content of hydrogen atoms in hydroxyl groups, carboxylic acid groups, etc.) is preferably 8.0 mmol / g or more, more preferably 10.5 mmol / g or more, and 11.0 mmol. / G or more is more preferable, 12.0 mmol / g or more is particularly preferable, and 13.0 mmol / g or more is most preferable. The upper limit is preferably 25.0 mmol / g or less, more preferably 23.0 mmol / g or less.

The upper limit of the molecular weight of the phenol compound is preferably 600 or less, more preferably 500 or less, further preferably 450 or less, and particularly preferably 400 or less. The lower limit is preferably 110 or more, and more preferably 300 or more.

The phenol compound may be used alone or in combination of two or more.
When the composition of the present invention contains a phenol compound, the content of the phenol compound is preferably 1.0 to 25.0% by mass, preferably 3.0 to 20.0% by mass, based on the total solid content of the composition. Is more preferable.
The composition of the present invention may contain a compound having a group capable of reacting with an epoxy compound described later (also referred to as “other active hydrogen-containing compound”) as a compound other than the phenol compound and the specific compound.
When the composition of the present invention contains a phenol compound and also contains other active hydrogen-containing compounds, the mass of the content of the other active hydrogen-containing compound with respect to the content of the phenol compound in the composition of the present invention. The ratio (content of other active hydrogen-containing compound / content of phenol compound) is preferably 0 to 1, more preferably 0 to 0.1, and even more preferably 0 to 0.05.

[Epoxy compound]
The composition of the present invention may further contain an epoxy compound.
The epoxy compound is a compound other than the specific compound. For example, even if the specific compound has an epoxy group, the specific compound does not correspond to an epoxy compound.
An epoxy compound is a compound having at least one epoxy group (oxylanyl group) in one molecule. Epoxy groups may or may not have substituents, if possible.
The number of epoxy groups contained in the epoxy compound is preferably 2 or more, more preferably 2 to 40, still more preferably 2 to 10, and particularly preferably 2 in one molecule.
The molecular weight of the epoxy compound is preferably 150 to 10000, more preferably 150 to 2000, and even more preferably 250 to 400.

The lower limit of the epoxy group content of the epoxy compound is preferably 2.0 mmol / g or more, more preferably 4.0 mmol / g or more, and further preferably 5.0 mmol / g or more. The upper limit is preferably 20.0 mmol / g or less, more preferably 15.0 mmol / g or less.
The epoxy group content is intended to be the number of epoxy groups contained in 1 g of the epoxy compound.
The epoxy compound is preferably liquid at room temperature (23 ° C.).

The epoxy compound may or may not exhibit liquid crystallinity.
That is, the epoxy compound may be a liquid crystal compound. In other words, a liquid crystal compound having an epoxy group can also be used as the epoxy compound.
Examples of the epoxy compound (which may be a liquid crystal epoxy compound) include a compound having a rod-like structure at least partially (a rod-like compound) and a compound having a disk-like structure at least partially. Be done.
Among them, a rod-shaped compound is preferable because the obtained heat conductive material has more excellent heat conductivity.
Hereinafter, the rod-shaped compound and the disk-shaped compound will be described in detail.

(Stick compound)
Examples of the epoxy compound which is a rod-shaped compound include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, and alkoxy-substituted phenyls. Examples thereof include pyrimidines, phenyldioxans, trans, and alkenylcyclohexylbenzonitriles. Not only low molecular weight compounds as described above, but also high molecular weight compounds can be used. The above-mentioned polymer compound is a polymer compound obtained by polymerizing a rod-shaped compound having a small molecule reactive group.
Preferred rod-shaped compounds include rod-shaped compounds represented by the following general formula (XXI).
Formula ^{^{^{^{(XXI): Q 1 -L 111}}}} -A 111 -L 113 -M-L 114 -A 112 -L 112 -Q 2

In the general formula (XXI), Q ¹ and Q ² are independent epoxy groups, and L ¹¹¹ , L ¹¹² , L ¹¹³ , and L ¹¹⁴ each independently represent a single bond or a divalent linking group. .. A ¹¹¹ and A ¹¹² each independently represent a divalent linking group (spacer group) having 1 to 20 carbon atoms. M represents a mesogen group.
Epoxy group of Q ¹ and Q ² may be substituted or may not have.

In the general formula (XXI), L ¹¹¹ , L ¹¹² , L ¹¹³ , and L ¹¹⁴ each independently represent a single bond or a divalent linking group.
The ^{divalent linking groups represented by L 111} , L ¹¹² , L ¹¹³ , and L ¹¹⁴ are independently -O-, -S-, -CO-, -NR ^112- , and -CO-O, respectively. -, -O-CO-O-, -CO ^{-NR 112-} , -NR ¹¹² -CO-, -O-CO-, -CH ₂ _{-O-, -O-CH 2-,} -O-CO-NR ^{^{112 -, - NR 112 -CO-}} O-, ^and, -NR ^{112 -CO-NR} 112 - is preferably a divalent linking group selected from the group consisting of. R ¹¹² is an alkyl group or a hydrogen atom having 1 to 7 carbon atoms.
Among them, L ¹¹³ and L ¹¹⁴ are preferably —O— independently of each other.
L ¹¹¹ and L ¹¹² are preferably single bonds independently of each other.

In the general formula (XXI), A ¹¹¹ and A ¹¹² each independently represent a divalent linking group having 1 to 20 carbon atoms.
The divalent linking group may contain heteroatoms such as non-adjacent oxygen and sulfur atoms. Of these, an alkylene group, an alkaneylene group, or an alkynylene group having 1 to 12 carbon atoms is preferable. The above-mentioned alkylene group, alkenylene group, or alkynylene group may or may not have an ester group.
The divalent linking group is preferably linear, and the divalent linking group may or may not have a substituent. Examples of the substituent include a halogen atom (fluorine atom, chlorine atom, and bromine atom), a cyano group, a methyl group, and an ethyl group.
Among them, A ¹¹¹ and A ¹¹² are each independently preferably an alkylene group having 1 to 12 carbon atoms, and more preferably a methylene group.

In the general formula (XXI), M represents a mesogen group, and examples of the mesogen group include known mesogen groups. Of these, a group represented by the following general formula (XXII) is preferable.
General formula (XXII):-(W ^1- L ¹¹⁵ ) _n- W ^2-

In the general formula (XXII), W ¹ and W ² independently represent a divalent cyclic alkylene group, a divalent cyclic alkaneylene group, an arylene group, or a divalent heterocyclic group, respectively. L ¹¹⁵ represents a single bond or a divalent linking group. n represents an integer of 1 to 4.

Examples of W ¹ and W ² include 1,4-cyclohexenediyl, 1,4-cyclohexanediyl, 1,4-phenylene, pyrimidine-2,5-diyl, pyridine-2,5-diyl, 1,3. 4-Thiadiazole-2,5-diyl, 1,3,4-oxadiazole-2,5-diyl, naphthalene-2,6-diyl, naphthalene-1,5-diyl, thiophene-2,5-diyl, And pyridazine-3,6-diyl. In the case of 1,4-cyclohexanediyl, it may be either a trans isomer or a cis structural isomer, or a mixture in any proportion. Of these, a transformer body is preferable.
W ¹ and W ² may each have a substituent. Examples of the substituent include the groups exemplified in the above-mentioned substituent group Y, and more specifically, a halogen atom (fluorine atom, chlorine atom, bromine atom, and iodine atom), a cyano group, and a carbon. An alkyl group having a number of 1 to 10 (for example, a methyl group, an ethyl group, a propyl group, etc.), an alkoxy group having 1 to 10 carbon atoms (for example, a methoxy group, an ethoxy group, etc.), and a group having 1 to 10 carbon atoms. An acyl group (for example, formyl group and acetyl group, etc.), an alkoxycarbonyl group having 1 to 10 carbon atoms (for example, a methoxycarbonyl group, an ethoxycarbonyl group, etc.), an acyloxy group having 1 to 10 carbon atoms (for example, an acyloxy group). Acetyloxy group, propionyloxy group, etc.), nitro group, trifluoromethyl group, difluoromethyl group and the like can be mentioned.
If W ¹ there are a plurality, W ¹ existing in plural numbers may each be the same or different.

In the general formula (XXII), L ¹¹⁵ represents a single bond or a divalent linking group. Specific examples of the divalent linking group represented by L ¹¹⁵ include the above-mentioned divalent linking groups represented by L ¹¹¹ to L ¹¹⁴ , and examples thereof include -CO-O- and -O-CO-. , -CH _2- O-, and -O-CH _2- .
When a ^{plurality of L 115s} are present, the plurality of L ^115s may be the same or different from each other.

The preferred skeleton of the basic skeleton of the mesogen group represented by the above general formula (XXII) is illustrated below. The mesogen groups may be substituted with substituents on these skeletons.

Among the above skeletons, the biphenyl skeleton is preferable in that the obtained heat conductive sheet has more excellent thermal conductivity.
The compound represented by the general formula (XXI) can be synthesized by referring to the method described in JP-A No. 11-513019 (WO97 / 00600).
The rod-shaped compound may be a monomer having a mesogen group described in JP-A-11-323162 and Patent No. 4118691.

Among them, the rod-shaped compound is preferably a compound represented by the general formula (E1).

In the general formula (E1), ^LE1 independently represents a single bond or a divalent linking group.
Of these, ^LE1 is preferably a divalent linking group.
The divalent linking groups are -O-, -S-, -CO-, -NH-, -CH = CH-, -C≡C-, -CH = N-, -N = CH-, -N = N—, an alkylene group which may have a substitution intention, or a group consisting of two or more of these is preferable, and —O—alkylene group— or −alkylene group—O— is more preferable.
The alkylene group may be linear, branched or cyclic, but a linear alkylene group having 1 to 2 carbon atoms is preferable.
A plurality of ^LE1s may be the same or different from each other.

In the general formula (E1), ^LE2 are independently single-bonded, -CH = CH-, -CO-O-, -O-CO-, -C (-CH ₃ ) = CH-, -CH =. C (-CH ₃ )-, -CH = N-, -N = CH-, -N = N-, -C≡C-, -N = N ⁺ (-O ^- )-, -N ⁺ (-O-) ^{^{^{^{-) = N -, - CH}}}} = N + (-O -) -, - N + (-O -) = CH -, - CH = CH-CO -, - CO-CH = CH -, - CH = C It represents (-CN)-or-C (-CN) = CH-.
Among ^{them, L E2} are each independently a single bond, -CO-O-, or, -O-CO- is preferred.
When there are a plurality of ^LE2s ^{, the plurality of LE2s} may be the same or different.

In the general formula (E1), ^LE3 may independently have a single bond or a substituent, respectively, and may have a 5-membered ring or a 6-membered ring aromatic ring group or a 5-membered ring or a 6-membered ring. Represents a non-aromatic ring group of, or a polycyclic group composed of these rings.
Examples of aromatic ring groups and non-aromatic ring group represented by L ^E3, which may have a substituent, 1,4-cyclohexane-diyl group, 1,4-cyclohexene-diyl group, 1,4 -Phenylene group, pyrimidin-2,5-diyl group, pyridine-2,5-diyl group, 1,3,4-thiasiazol-2,5-diyl group, 1,3,4-oxadiazol-2,5 Examples thereof include a diyl group, a naphthalene-2,6-diyl group, a naphthalene-1,5-diyl group, a thiophene-2,5-diyl group, and a pyridazine-3,6-diyl group. In the case of a 1,4-cyclohexanediyl group, it may be either a trans isomer or a cis structural isomer, or a mixture in any proportion. Above all, a transformer body is preferable.
Among ^{them, L E3} represents a single bond, 1,4-phenylene group, or 1,4-cyclohexene-diyl group are preferable.
Substituent having a group represented by L ^E3 each independently represent an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, or, preferably an acetyl group, an alkyl group (preferably having a carbon number of 1) Gayori preferable.
When a plurality of substituents are present, the substituents may be the same or different.
When there are a plurality of ^LE3s ^{, the plurality of LE3s} may be the same or different.

In the general formula (E1), pe represents an integer of 0 or more.
If pe is the integer of 2 or more, there exist a plurality of ^{^(-L} E3 -L ^E2 -) may each be the same or different.
Among them, pe is preferably 0 to 2, more preferably 0 or 1, and even more preferably 0.

In the general formula (E1), ^LE4 independently represents a substituent.
The substituent is preferably an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, or an acetyl group, and more preferably an alkyl group (preferably 1 carbon number).
A plurality of ^LE4s may be the same or different from each other. Further, when le described below is an integer of 2 or more, a plurality of ^LE4s ^{existing in the same (LE4} ) _le may be the same or different.

In the general formula (E1), le independently represents an integer of 0 to 4.
Among them, le is preferably 0 to 2 independently of each other.
A plurality of le's may be the same or different from each other.

The rod compound preferably has a biphenyl skeleton.
In other words, the epoxy compound preferably has a biphenyl skeleton, and the epoxy compound in this case is more preferably a rod-shaped compound.

(Disc-shaped compound)
The epoxy compound, which is a disk-shaped compound, has a disk-shaped structure at least partially.
The disc-like structure has at least an alicyclic or aromatic ring. In particular, when the disk-shaped structure has an aromatic ring, the disk-shaped compound can form a columnar structure by forming a stacking structure by π-π interaction between molecules.
As a disk-shaped structure, specifically, Angew. Chem. Int. Ed. Examples thereof include the triphenylene structure described in 2012, 51, 7990-7793 or JP-A-7-306317, and the tri-substituted benzene structure described in JP-A-2007-2220 and JP-A-2010-244038.

The disk-shaped compound preferably has three or more epoxy groups. A cured product of an epoxy compound containing a disk-shaped compound having three or more epoxy groups tends to have a high glass transition temperature and high heat resistance.
The number of epoxy groups contained in the disk-shaped compound is preferably 8 or less, and more preferably 6 or less.

Specific examples of the disk-shaped compound include C.I. Destrade et al. , Mol. Crysr. Liq. Cryst. , Vol. 71, page 111 (1981); Chemical Society of Japan, Quarterly Review of Chemistry, No. 22, Liquid crystal chemistry, Chapter 5, Chapter 10, Section 2 (1994); B. Kohne et al. , Angew. Chem. Soc. Chem. Comm. , Page 1794 (1985); Zhang et al. , J. Am. Chem. Soc. , Vol. Examples of the compounds described in 116, page 2655 (1994), and Japanese Patent No. 4592225 include compounds in which at least one (preferably three or more) ends are epoxy groups.
Examples of the disk-shaped compound include Angew. Chem. Int. Ed. The triphenylene structure described in 2012, 51, 7990-7793, and JP-A-7-306317, and the tri-substituted benzene structure described in JP-A-2007-2220 and JP-A-2010-2404038 are terminal. Examples thereof include compounds having at least one (preferably three or more) epoxy groups.

(Other epoxy compounds)
Examples of other epoxy compounds other than the above-mentioned epoxy compounds include epoxy compounds represented by the general formula (BN).

In the general formula (DN), ^nDN represents an integer of 0 or more, preferably 0 to 5, and more preferably 1.
^RDN represents a single bond or a divalent linking group. The divalent linking group includes -O-, -O-CO-, -CO-O-, -S-, an alkylene group (preferably 1 to 10 carbon atoms), and an arylene group (the carbon number is preferably 1 to 10). 6 to 20 is preferable), or a group composed of a combination thereof is preferable, an alkylene group is more preferable, and a methylene group is more preferable.

Examples of other epoxy compounds include compounds in which the epoxy group is fused. Examples of such a compound include 3,4: 8,9-diepoxybicyclo [4.3.0] nonane and the like.

Other epoxy compounds include, for example, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, and bisphenol AD type epoxy compounds, which are glycidyl ethers such as bisphenol A, F, S, and AD. Etc .; hydrogenated bisphenol A type epoxy compound, hydrogenated bisphenol AD type epoxy compound, etc .; phenol novolac type glycidyl ether (phenol novolac type epoxy compound), cresol novolac type glycidyl ether (cresol novolac type epoxy compound), bisphenol A Novolak type glycidyl ether, etc .; Dicyclopentadiene type glycidyl ether (dicyclopentadiene type epoxy compound); Dihydroxypentadiene type glycidyl ether (dihydroxypentadiene type epoxy compound); Polyhydroxybenzene type glycidyl ether (polyhydroxybenzene type) Epoxy compounds); benzenepolycarboxylic acid type glycidyl esters (benzenepolycarboxylic acid type epoxy compounds); and trisphenol methane type epoxy compounds.

The epoxy compound may be used alone or in combination of two or more.
When the composition of the present invention contains an epoxy compound, the content of the epoxy compound is preferably 1.0 to 25.0% by mass, preferably 3.0 to 20.0% by mass, based on the total solid content of the composition. Is more preferable.

The composition of the present invention preferably contains at least one of the above-mentioned phenol compound and epoxy compound.
In this case, as described above, the composition may contain only the phenol compound among the phenol compound and the epoxy compound (it may be substantially free of the epoxy compound), or may contain only the epoxy compound (it may contain only the epoxy compound). It may be substantially free of phenolic compounds) or both.
When the composition of the present invention contains an epoxy compound and a phenol compound, respectively, the ratio of the content of the epoxy compound to the content of the phenol compound in the composition is the ratio of the epoxy group of the epoxy compound to the hydroxyl group of the phenol compound. The equivalent ratio (number of epoxy groups / number of hydroxyl groups) is preferably 30/70 to 70/30, more preferably 35/65 to 65/35.
When the composition of the present invention contains an epoxy compound and a phenol compound, respectively, the ratio of the content of the epoxy compound to the content of the phenol compound in the composition is the activity of the epoxy group of the epoxy compound and the activity of the phenol compound. The equivalent ratio (number of epoxy groups / number of active hydrogens) with hydrogen (hydrogen atom in hydroxyl group, etc.) is preferably 30/70 to 70/30, and more preferably 35/65 to 65/35. preferable.

Further, the number of epoxy groups contained in the epoxy compound and the number of epoxy groups contained in the specific compound with respect to the total number of hydroxyl groups contained in the phenol compound and the number of hydroxyl groups contained in the specific compound in the composition. The ratio of the total number of epoxy groups (number of epoxy groups / number of hydroxyl groups) is preferably 30/70 to 70/30, more preferably 40/60 to 60/40, and 42/58. An amount of about 58/42 is more preferable.
In this case, the composition may contain only one of the epoxy compound and the phenol compound, may contain both, or may not contain both.

When the composition contains a specific compound having an epoxy group, a specific compound having an active hydrogen, and / or other active hydrogen-containing compound, the total content of the epoxy compound and the specific compound having an epoxy group is used. The ratio of the total content of the phenol compound, the specific compound having active hydrogen, and other active hydrogen-containing compounds is the equivalent ratio (epoxide group) of the epoxy group in the system to the active hydrogen (hydrogen atom at the hydroxyl group, etc.). (Number of compounds / number of active hydrogens) is preferably 30/70 to 70/30, more preferably 40/60 to 60/40, and even more preferably 42/58 to 58/42. ..

When the composition of the present invention contains both an epoxy compound and a phenol compound, the total content of the phenol compound and the epoxy compound in the composition is preferably 5 to 90% by mass with respect to the total mass of the solid content. 10 to 50% by mass is more preferable, and 15 to 40% by mass is further preferable.

[Inorganic particles]
The composition for forming a heat conductive material of the present invention contains inorganic particles.
Examples of the inorganic particles include inorganic oxides such as iron oxide, silica (SiO ₂ ), alumina (Al ₂ O ₃ ), TiO ₂ , BaTIO ₃ , and ZrO ₂ ; inorganic nitrides such as aluminum nitride and silicon nitride; Examples thereof include fine particles such as sparingly soluble ionic crystals such as calcium oxide, barium fluoride, and barium sulfate; and clays such as montmorillonite.

In the present invention, the inorganic particles are preferably an inorganic nitride or an inorganic oxide, and more preferably an inorganic nitride, because the obtained heat conductive material has better thermal conductivity.
Specific examples of the inorganic nitride include boron nitride (BN), carbon nitride (C ₃ N ₄ ), silicon nitride (Si ₃ N ₄ ), gallium nitride (GaN), indium nitride (InN), and nitride. Aluminum (AlN), Chromium Nitride (Cr ₂ N), Copper Nitride (Cu ₃ N), Iron Nitride (Fe ₄ N or Fe ₃ N), Lantern Nitride (La _{N), Lithium Nitride (Li 3} N), Magnesium Nitride ( Mg ₃ N ₂ ), molybdenum nitride (Mo ₂ N), niobium nitride (NbN), tantalum nitride (TaN), titanium nitride (TiN), tungsten nitride (W ₂ N, WN ₂ , or WN), yttrium nitride (WN) YN), zirconium nitride (ZrN) and the like can be mentioned.
The above-mentioned inorganic nitrides may be used alone or in combination of two or more.
The inorganic nitride preferably contains at least one selected from the group consisting of a boron atom, an aluminum atom, and a silicon atom in that the obtained heat conductive material has more excellent thermal conductivity. More specifically, the inorganic nitride is preferably boron nitride, aluminum nitride, or silicon nitride, more preferably boron nitride or aluminum nitride, and even more preferably boron nitride.

The shape of the inorganic particles is not particularly limited, and examples thereof include rice granules, spheres, cubes, spindles, scales, agglutinates, and indefinite shapes. Of these, the shape of the particles is preferably scaly and agglutinating.
Further, the inorganic particles having different shapes may be used alone or in combination of two or more.

The size of the inorganic particles is not particularly limited, but the average particle size of the inorganic particles is preferably 500 μm or less, more preferably 300 μm or less, still more preferably 200 μm or less, in that the dispersibility of the inorganic particles is more excellent. The lower limit is not particularly limited, but from the viewpoint of handleability, 10 nm or more is preferable, and 100 nm or more is more preferable.
As the method for measuring the average particle size, 100 inorganic particles are randomly selected using an electron microscope, the particle size (major axis) of each inorganic particle is measured, and they are calculated by arithmetic mean. .. When using a commercially available product, the catalog value may be used.

In the composition of the present invention, the content of the inorganic particles is preferably 60 to 90% by mass, more preferably 70 to 85% by mass, still more preferably 75 to 80% by mass, based on the total solid content of the composition.
In the present specification, the solid content of the composition is intended to mean all components excluding the solvent when the composition contains a solvent, and if it is a component other than the solvent, it is regarded as a solid content even if it is a liquid component. ..

The average particle size of the inorganic particles contained in the composition is preferably larger than 3 μm, more preferably 4 to 50 μm, in that the heat conductive material is more excellent in heat conductivity.

Further, the inorganic substances preferably have inorganic substances having different average particle diameters. For example, both the inorganic substance X having an average particle size of 20 μm or more and the inorganic substance Y having an average particle size of less than 20 μm are used. It is also preferable to include it.
The average particle size of the inorganic substance X is preferably 20 to 300 μm, more preferably 30 to 200 μm. The average particle size of the inorganic substance Y is preferably 10 nm or more and less than 20 μm, and more preferably 100 nm or more and 15 μm or less.
The inorganic substance X is preferably an inorganic nitride or an inorganic oxide, more preferably an inorganic nitride, and even more preferably boron nitride.
The inorganic substance Y is preferably an inorganic nitride or an inorganic oxide, more preferably boron nitride or aluminum oxide, and even more preferably boron nitride.
As the inorganic substance X and the inorganic substance Y, each of them may be used alone or in combination of two or more.
The mass ratio of the content of the inorganic substance X to the content of the inorganic substance Y (content of the inorganic substance X / content of the inorganic substance Y) is preferably 50/50 to 99/1, and 75/25 to 97/3. Is more preferable.
Further, the content of boron nitride in the inorganic particles is preferably 55% or more, more preferably 75% or more, because the heat conductive material formed by the composition has more excellent thermal conductivity.

[Curing accelerator]
The composition of the present invention may further contain a curing accelerator because the heat conductive material is more excellent in heat conductivity.
Examples of the curing accelerator include triphenylphosphine, a boron trifluoride amine complex, and the compounds described in paragraph 0052 of JP2012-67225A. In addition, 2-methylimidazole (trade name; 2MZ), 2-undecylimidazole (trade name: C11-Z), 2-heptadecylimidazole (trade name: C17Z), 1,2-dimethylimidazole (trade name). 1.2DMZ), 2-ethyl-4-methylimidazole (trade name: 2E4MZ), 2-phenylimidazole (trade name: 2PZ), 2-phenyl-4-methylimidazole (trade name: 2P4MZ), 1-benzyl -2-Methylimidazole (trade name: 1B2MZ), 1-benzyl-2-phenylimidazole (trade name: 1B2PZ), 1-cyanoethyl-2-methylimidazole (trade name: 2MZ-CN), 1-cyanoethyl-2- Undecylimidazole (trade name: C11Z-CN), 1-cyanoethyl-2-phenylimidazolium trimerite (trade name: 2PZCNS-PW), 2,4-diamino-6- [2'-methylimidazolyl- (1) ')]-Ethyl-s-triazine (trade name; 2MZ-A), 2,4-diamino-6- [2'-undecylimidazolyl- (1')]-ethyl-s-triazine (trade name; C11Z) -A), 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1')]-ethyl-s-triazine (trade name; 2E4MZ-A), 2,4-diamino- 6- [2'-methylimidazolyl- (1')] -ethyl-s-triazine isocyanuric acid adduct (trade name; 2MA-OK), 2-phenyl-4,5-dihydroxymethylimidazole (trade name; 2PHZ-) PW), 2-phenyl-4-methyl-5-hydroxymethylimidazole (trade name: 2P4MHZ-PW), and imidazole-based curing accelerators such as 1-cyanoethyl-2-phenylimidazole (trade name: 2PZ-CN). Etc. (all manufactured by Shikoku Kasei Kogyo Co., Ltd.).
The curing accelerator may be used alone or in combination of two or more.
When the composition contains a curing accelerator, the content of the curing accelerator is preferably 0.01 to 10% by mass, preferably 0.1 to 5% by mass, based on the total content of the epoxy compound and the specific compound having an epoxy group. Is more preferable.

[Dispersant]
The composition of the present invention may further contain a dispersant.
When the composition contains a dispersant, the dispersibility of the inorganic substance in the composition is improved, and more excellent thermal conductivity and adhesiveness can be realized.

The dispersant can be appropriately selected from commonly used dispersants. For example, DISPERBYK-106 (manufactured by BYK-Chemie GmbH), DISPERBYK-111 (manufactured by BYK-Chemie GmbH), ED-113 (manufactured by Kusumoto Kasei Co., Ltd.), Ajisper PN-411 (manufactured by Ajinomoto Fine-Techno), and REB122- 4 (manufactured by Hitachi Kasei Kogyo) and the like.
The dispersant may be used alone or in combination of two or more.
When the composition of the present invention contains a dispersant, the content of the dispersant is preferably 0.01 to 10% by mass, more preferably 0.1 to 5% by mass, based on the content of the inorganic substance.

〔solvent〕
The composition of the present invention may further contain a solvent.
The type of solvent is not particularly limited, and an organic solvent is preferable. Examples of the organic solvent include cyclopentanone, cyclohexanone, ethyl acetate, methyl ethyl ketone, dichloromethane, tetrahydrofuran and the like.
When the composition of the present invention contains a solvent, the content of the solvent is preferably such that the solid content concentration of the composition is 20 to 90% by mass, more preferably 30 to 85% by mass, and 40 to 40 to 80%. An amount of 85% by mass is more preferable.

[Method for producing composition]
The method for producing the composition of the present invention is not particularly limited, and a known method can be adopted. For example, the above-mentioned various components can be mixed and produced. When mixing, various components may be mixed all at once or sequentially.
The method of mixing the components is not particularly limited, and a known method can be used. The mixer used for mixing is preferably a liquid disperser. And a homogenizer. The mixing device may be used alone or in combination of two or more. Deaeration treatment may be performed before and after mixing and / or at the same time.

[Manufacturing method of heat conductive material]
The composition of the present invention is cured to obtain a heat conductive material.
The curing method of the composition of the present invention is not particularly limited, but a thermosetting reaction is preferable.
The heating temperature during the thermosetting reaction is not particularly limited. For example, it may be appropriately selected in the range of 50 to 250 ° C. Further, when the thermosetting reaction is carried out, heat treatments having different temperatures may be carried out a plurality of times.
The curing treatment is preferably performed on a film-like or sheet-like composition. Specifically, for example, the composition may be applied to form a film and a curing reaction may be carried out.
When performing the curing treatment, it is preferable to apply the composition on the substrate to form a coating film and then cure. At this time, a different base material may be brought into contact with the coating film formed on the base material, and then the curing treatment may be performed. The cured product (heat conductive material) obtained after curing may or may not be separated from one or both of the substrates.
Further, when performing the curing treatment, the composition may be applied on different substrates to form coating films, and the curing treatment may be performed in a state where the obtained coating films are in contact with each other. The cured product (heat conductive material) obtained after curing may or may not be separated from one or both of the substrates.

The curing treatment may be completed when the composition is in a semi-cured state. Further, after the composition is made into a semi-cured state, further curing treatment may be carried out to complete the curing.
A curing treatment for bringing the composition into a semi-hardened state (hereinafter, also abbreviated as "semi-hardening treatment") and a curing treatment for completely curing (hereinafter, also abbreviated as "main curing treatment") are performed. It may be divided into separate steps.

For example, in the semi-curing treatment, a composition is applied onto a base material to form a coating film, and then the coating film on the base material is heated without pressure to form a semi-cured heat conductive material (hereinafter referred to as “semi-cured material”). It may also be abbreviated as “semi-hardened film”), or it may be used as a semi-cured film by heating the coating film on the substrate while also using press processing. When the press working is performed, the press working may be carried out before or after the above heating or the like, or may be carried out during the press working. When press working is performed in the semi-hardened film, it may be easy to adjust the film thickness of the obtained semi-hardened film and / or reduce the amount of voids in the semi-hardened film.
In the semi-hardening treatment, the semi-hardening treatment may be performed in a state where the coating films formed on different substrates are laminated, or the semi-hardening treatment may be performed without laminating the coating films. The semi-hardening treatment may be carried out in a state where the coating film formed from the composition is further in contact with a material other than the coating film.

The obtained semi-cured film may be used as it is as a heat conductive material, or may be used as a completely cured heat conductive material after the semi-hard film is further subjected to the main curing treatment.
In the main curing treatment, the semi-hardened film may be heated as it is without pressure, or may be heated after being pressed or while being pressed. At this time, in the main curing treatment, the main curing treatment may be performed in a state where the separate semi-hardened films are laminated, or the main curing treatment may be performed without laminating the semi-hardened films.
Further, the main curing treatment may be carried out in a state where the semi-hardened film is arranged so as to be in contact with the device or the like to be used. It is also preferable that the device and the heat conductive material of the present invention are adhered to each other by this hardening treatment.

There is no limitation on the press used for the press working that may be performed during the semi-hardening treatment and / or the curing treatment in the main curing treatment, and for example, a flat plate press or a roll press may be used. ..
When a roll press is used, for example, a base material with a coating film obtained by forming a coating film on the base material is sandwiched between a pair of rolls in which two rolls face each other, and the above pair of rolls is used. It is preferable to apply pressure in the film thickness direction of the coating film-coated substrate while rotating the coating film-coated substrate. In the above-mentioned base material with a coating film, the base material may be present on only one side of the coating film, or the base material may be present on both sides of the coating film. The base material with a coating film may be passed through the roll press only once or may be passed a plurality of times.
In the semi-hardening treatment and / or the curing treatment in the main curing treatment or the like, only one of the treatment by the flat plate press and the treatment by the roll press may be carried out, or both may be carried out.

For the production of heat conductive materials including curing reaction, refer to "High heat conductive composite material" (CMC Publishing, by Yutaka Takezawa).

The shape of the heat conductive material is not particularly limited, and can be molded into various shapes depending on the application. A typical shape of the molded heat conductive material is, for example, a sheet shape.
That is, it is also preferable that the heat conductive material obtained by using the composition of the present invention is a heat conductive sheet (hereinafter, also abbreviated as "heat conductive sheet of the present invention").
Further, the thermal conductivity of the heat conductive material obtained by using the composition of the present invention is preferably isotropic rather than anisotropic.

The heat conductive material is preferably insulating (electrically insulating). In other words, the composition of the present invention is preferably a thermally conductive insulating composition.
For example, the volume resistivity of the heat conductive material at 23 ° C. and 65% relative humidity ^{is preferably 10 10} Ω · cm or more, more preferably 10 ¹² Ω · cm or more, and even more preferably 10 ¹⁴ Ω · cm or more. The upper limit is not particularly limited, but is usually 10 ¹⁸ Ω · cm or less.

[Heat conduction sheet]
The heat conductive material obtained by using the composition of the present invention may be used in combination with other members other than the members formed from the composition of the present invention.
For example, the sheet-shaped heat conductive material (heat conductive sheet) may be combined with another sheet-shaped support of the layer formed from the composition of the present invention.
Examples of the sheet-shaped support include a plastic film, a metal film, and a glass plate. Examples of the material of the plastic film include polyester such as polyethylene terephthalate (PET), polycarbonate, acrylic resin, epoxy resin, polyurethane, polyamide, polyolefin, cellulose derivative, and silicone. Examples of the metal film include a copper film.
The film thickness of the sheet-shaped heat conductive material (heat conductive sheet) is preferably 100 to 300 μm, more preferably 150 to 250 μm.

Further, it can be molded into a heat conductive multilayer sheet (hereinafter, also abbreviated as "heat conductive multilayer sheet of the present invention") in which an adhesive layer or an adhesive layer is arranged on one side or both sides of the heat conductive sheet of the present invention. can.
By bonding the heat conductive material to an object such as a device to which heat should be transferred through such an adhesive layer and / or an adhesive layer, a stronger bond between the heat conductive material and the object is performed. Can be realized.
For example, as the heat conductive multilayer sheet of the present invention, the heat conductive multilayer sheet having the heat conductive sheet of the present invention and an adhesive layer or an adhesive layer provided on one side or both sides of the heat conductive sheet. May be produced.
In addition, one of the adhesive layer and the pressure-sensitive adhesive layer may be provided on one side or both sides of the heat conductive sheet, respectively, or both may be provided. An adhesive layer may be provided on one surface of the heat conductive sheet, and an adhesive layer may be provided on the other surface. Further, the adhesive layer and / or the adhesive layer may be partially provided on one side or both sides of the heat conductive sheet, or may be provided on the entire surface.
As described above, in the present invention, the heat conductive material such as the heat conductive sheet may be in a semi-cured state (semi-cured film), and the heat conductive sheet in the heat conductive multilayer sheet may be in a semi-cured state. .. The adhesive layer in the heat conductive multilayer sheet may be cured, semi-cured, or uncured.

<Adhesive layer>
The adhesive layer preferably contains at least one adhesive compound (resin and / or low molecular weight compound, etc.).
The adhesive layer may further contain other components such as fillers, if desired.

As the compound having adhesiveness, a compound having insulating property, adhesiveness and / or flexibility at the time of adhesion is preferable.
Above all, from the viewpoint of adhesiveness and insulating property, it is preferable to contain at least one selected from the group consisting of a polyimide resin, a modified polyimide resin, a polyamide-imide resin, a modified polyamide-imide resin, and an epoxy compound.
The epoxy compound may be an epoxy resin containing an acrylic modified rubber.

Examples of the polyimide resin and the modified polyimide resin include Iupicort FS-100L (manufactured by Ube Industries, Ltd.), Semicofine SP-300, SP-400, SP-800 (manufactured by Toray Industries, Inc.), and Uimide series (manufactured by Toray Industries, Inc.). Products such as Unitika Ltd.) can be mentioned.

Examples of the above-mentioned polyamide-imide resin and modified polyamide-imide resin include KS series (manufactured by Hitachi Kasei Kogyo Co., Ltd.), Vilomax series (manufactured by Toyo Spinning Co., Ltd.), Toron (manufactured by Solvay Advanced Polymers Co., Ltd.) and the like. ..
Above all, from the viewpoint of high heat resistance and high adhesiveness, it is preferable to use a modified polyamide-imide resin represented by the KS series (manufactured by Hitachi Kasei Kogyo Co., Ltd.).

The polyimide resin, the polyamide-imide resin, and the modified polyamide-imide resin used for the adhesive layer may be used alone or in combination of two or more.
Further, these resins are usually in a varnish state in which the resin is dissolved in a solvent, and can be directly applied to a support such as a PET film and dried to form a film and used as an adhesive layer.

Moreover, you may use an epoxy compound as a compound having adhesiveness. Specifically, for example, an epoxy composition containing an epoxy compound, a curing agent thereof, and a curing agent accelerator may be used as the adhesive layer. It is also preferable to add glycidyl acrylate to the epoxy composition.
For details of the epoxy composition, for example, the descriptions of JP-A-2002-134531, JP-A-2002-226996, and JP-A-2003-221573 can also be referred to.

The epoxy compound used for the adhesive layer is not particularly limited as long as it cures and exhibits an adhesive action. For example, when a bisphenol A type or bisphenol F type liquid epoxy compound having a molecular weight of 500 or less is used, the fluidity at the time of lamination can be improved. A polyfunctional epoxy compound may be added for the purpose of increasing the Tg (glass transition temperature), and examples of the polyfunctional epoxy compound include a phenol novolac type epoxy compound and a cresol novolac type epoxy compound.
As the epoxy compound used for the adhesive layer, the epoxy compound described as the epoxy compound that can be used in the composition of the present invention may be used.

Examples of the curing agent for the epoxy compound include polyamide, polyamine, acid anhydride, polysulfide, boron trifluoride, or phenol compound (phenol novolac resin, bisphenol, which is a compound having two or more phenolic hydroxyl groups in one molecule. A, bisphenol F, bisphenol S, etc.). From the viewpoint of excellent electrolytic corrosion resistance during moisture absorption, it is also preferable to use a phenol compound such as phenol novolac resin, bisphenol novolak resin, or cresol novolak resin.
Further, as the curing agent, the phenol compound described as the phenol compound that can be used in the composition of the present invention may be used.

When using a curing agent, it is preferable to use a curing accelerator together with the curing agent. It is also preferable to use triphenylphosphine or imidazole as the curing accelerator. Examples of the imidazole include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-cyanoethyl-2-phenylimidazolium trimerite. The imidazoles are commercially available from Shikoku Kasei Kogyo Co., Ltd. under the trade names of 2E4MZ, 2PZ-CN, and 2PZ-CNS.

The epoxy compound used for the adhesive layer is also preferably used in combination with a high molecular weight resin compatible with the epoxy compound.
Examples of the high molecular weight resin compatible with the epoxy compound include a high molecular weight epoxy compound, a functional group-containing rubber having a large polarity, and a functional group-containing reactive rubber having a large polarity.
Examples of the highly polar functional group-containing reactive rubber include acrylic modified rubber in which a highly polar functional group such as a carboxyl group is added to acrylic rubber.

Here, "compatible with an epoxy compound" means a property of forming a homogeneous admixture without separating from the epoxy compound and separating into two or more phases after curing.
The weight average molecular weight of the high molecular weight resin is not particularly limited. From the viewpoint of reducing the tackiness of the adhesive in the B stage and improving the flexibility during curing, the weight average molecular weight is preferably 30,000 or more.

The high molecular weight epoxy compound is a high molecular weight epoxy compound having a molecular weight of 30,000 to 80,000, and an ultra high molecular weight epoxy compound having a molecular weight of more than 80,000 (Special Fair 7-59617, Special Fair 7-59618, Special Fair). 7-59619, Tokuhei 7-59620, Tokuhei 7-64911, Tokuhei 7-68327), all of which are manufactured by Hitachi Kasei Kogyo Co., Ltd. As a functional group-containing reactive rubber having a high polarity, HTR-860P (trade name) of a carboxyl group-containing acrylic rubber is sold by Nagase ChemteX Corporation, for example.

When a high molecular weight resin that is compatible with the epoxy compound and has a weight average molecular weight of 30,000 or more is used, the amount added is 10 parts by mass or more when the resin constituting the adhesive layer is 100 parts by mass. It is preferably 40 parts by weight or less.
When it is 10 parts by mass or more, it is easy to improve the flexibility, tackiness, and / or crack suppression of the phase containing the epoxy compound as the main component (hereinafter referred to as the epoxy compound phase), and the insulating property is improved. Hard to drop. When it is 40 parts by weight or less, the Tg of the epoxy compound phase can be improved.

The weight average molecular weight of the high molecular weight epoxy compound is preferably 20,000 or more and 500,000 or less. In this range, the strength and / or flexibility in the sheet state and / or the film state is improved, and the tackiness is easily suppressed.

The polyamide-imide resin, the modified polyamide-imide resin, and the epoxy compound preferably used for the adhesive layer may be used alone or in combination of two or more.
Further, these compounds may be a mixture in a varnish state in which the compounds are dissolved in a solvent. By applying such a mixture directly to a support such as a PET film and drying the solvent, the compound can be formed into a film and used as an adhesive layer.

(Silane coupling agent)
A silane coupling agent may be added to the adhesive layer in order to improve the interfacial bond between different materials.
Examples of the silane coupling agent include γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, and N-β-. Aminoethyl-γ-aminopropyltrimethoxysilane can be mentioned.
Of these, γ-mercaptopropyltrimethoxysilane or γ-aminopropyltriethoxysilane is preferable from the viewpoint of adhesive strength.
When the adhesive layer contains a silane coupling agent, the blending amount thereof is 0.1 to 10% by mass with respect to 100 parts by mass of the above-mentioned adhesive compound from the viewpoint of the effect of the addition and / or the influence on heat resistance. Part is preferable.

(Filler)
The adhesive layer may contain a filler (preferably an inorganic filler).
When the adhesive layer contains a filler, the handleability and thermal conductivity of the adhesive layer are improved. Further, it is possible to impart flame retardancy, adjust the melt viscosity, impart thixotropic property, and / or improve the surface hardness.

When the adhesive layer contains a filler, its content is not particularly limited. Above all, the content is preferably 20 to 50 parts by volume with respect to 100 parts by volume of the compound having the adhesiveness contained in the adhesive layer.
From the viewpoint of the effect of blending, the content is more preferably 30 parts by volume or more. Further, from the viewpoint of optimizing the storage elastic modulus of the adhesive, improving the adhesiveness, and / or suppressing the decrease in insulating property by suppressing voids, the content may be 50 parts by volume or less. preferable.

Examples of the inorganic filler include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina (aluminum oxide), aluminum nitride, aluminum borate whisker, and boron nitride. , Crystalline silica, amorphous silica, silicon nitride, talc, mica, and barium sulfate.
Among them, alumina, boron nitride, or aluminum nitride is preferable in that it has good heat dissipation because of its high thermal conductivity, it is easy to control impurities, and it has good heat resistance and insulating properties.
One type of filler may be used alone, or two or more types may be used.

The average particle size of the filler contained in the adhesive layer is not particularly limited. For example, from the viewpoint of thermal conductivity, 0.1 to 10 μm is preferable, and 0.2 to 5 μm is more preferable.

The content of the filler in the adhesive layer is 50% by volume or less (for example, 20% by volume or more and 50% by volume or less) with respect to the total volume of the adhesive layer from the viewpoint of balancing adhesiveness and thermal conductivity. It is also preferable.

In particular, the adhesive layer contains at least one selected from the group consisting of an epoxy compound and a modified polyamideimide resin as a compound having adhesiveness, and at least one selected from the group consisting of alumina and silicon oxide as a filler. The content of the filler is 25 parts by volume or more and 100 parts by volume or less with respect to 100 parts by volume of the adhesive having adhesiveness, and the average particle size of the filler is 0.2 to 5 μm. It is preferable from the viewpoint of.

The film thickness of the adhesive layer is preferably 1 to 16 μm, more preferably 2 to 15 μm, further preferably 3 to 14 μm, and particularly preferably 4 to 12 μm from the viewpoint of thermal conductivity and adhesiveness.
The film thickness of the adhesive layer can be measured using a micrometer, a stylus type film thickness meter, a needle type film thickness meter, or the like.

<Adhesive layer>
As the material of the pressure-sensitive adhesive layer, various pressure-sensitive adhesives and / or thermosetting materials and the like, which have the required heat resistance and heat conduction performance, can be used without particular limitation. Further, a pressure-sensitive adhesive may be used in which various heat-conductive fillers are mixed in the pressure-sensitive adhesive layer to improve the heat-conductivity.

Examples of the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer include an acrylic pressure-sensitive adhesive, an olefin-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, a natural rubber-based pressure-sensitive adhesive, and a synthetic rubber-based pressure-sensitive adhesive.
Acrylic adhesives or olefin adhesives are preferable because outgas is less likely to be generated in applications near semiconductors in electronic devices. From the viewpoint of heat resistance, a silicone-based adhesive containing a silicone resin as a main raw material is preferable.
The "adhesive containing a silicone resin as a main raw material" is a pressure-sensitive adhesive containing 60% by mass or more (preferably 80% by mass or more) of a silicone resin.
Examples of the pressure-sensitive adhesive using a silicone resin as a main raw material include a peroxide-crosslinked (cured) type silicone-based pressure-sensitive adhesive and an addition-reaction type silicone-based pressure-sensitive adhesive. Above all, an addition reaction type silicone-based pressure-sensitive adhesive is preferable because it has high thickness accuracy when it is made into a thin layer and it is easy to form a pressure-sensitive adhesive layer by a transfer method.

Examples of the addition reaction type silicone adhesive include a silicone rubber and a silicone resin, and if necessary, a cross-linking agent, a filler, a plasticizer, an antiaging agent, an antioxidant, and / or a coloring agent. Examples thereof include adhesives containing additives such as (pigments, dyes, etc.).

The silicone rubber is not particularly limited as long as it is a silicone-based rubber component, but is a silicone rubber containing an organopolysiloxane having a phenyl group (particularly, an organopolysiloxane having methylphenylsiloxane as a main constituent unit). Is preferable. Various functional groups such as vinyl groups may be introduced into the organopolysiloxane in such silicone rubber, if necessary.

As the silicone resin is not particularly limited as long as it is a resin of silicone used in the silicone adhesive, for example, units consisting of constituent units "R ₃ SiO _1/2", from the constituent unit "SiO _2" comprising units, units consisting of constituent units "RSiO _3/2", and consists of at least one kind of unit selected from the group consisting of units consisting of constituent units "R ₂ SiO" (co) polymer Examples include silicone resins containing organopolysiloxane. In addition, R in the said structural unit represents a hydrocarbon group or a hydroxyl group.

Examples of the acrylic pressure-sensitive adhesive include homopolymers and copolymers of (meth) acrylic acid and / or (meth) acrylic acid ester.

Among them, butyl acrylate, 2-ethylhexyl acrylate, etc. are the main raw materials for acrylic pressure-sensitive adhesives because they are excellent in flexibility, chemical stability, processability, and / or controllability of adhesiveness. A poly (meth) acrylic acid ester-based polymer compound as a component is preferable.

The above polymer compound is obtained by copolymerizing one or more monomers selected from butyl acrylate, ethyl acrylate, diethylhexyl acrylate and the like with acrylate, acrylonitrile, and / or hydroxyethyl acrylate, and the like. A copolymer having a structure in which a polar group such as a COOH group, -CN group, or -OH group is introduced is preferable.

Further, a crosslinked structure may be introduced into the acrylic pressure-sensitive adhesive as long as the flexibility is not impaired. By introducing a crosslinked structure, it is easy to improve long-term adhesion retention and film strength. For example, a crosslinked structure can be introduced by reacting a polymer having a polar group such as an −OH group with a compound having a functional group that binds to the polar group such as a plurality of isocyanate groups or an epoxy group with the polar group. ..

[Device with thermal conductive layer]
The heat conductive material obtained by using the composition of the present invention can be used as a heat radiating material such as a heat radiating sheet, and can be used for heat radiating applications of various devices. More specifically, a device with a heat conductive layer can be produced by arranging a heat conductive layer containing the heat conductive material of the present invention on the device, and heat generated from the device can be efficiently dissipated by the heat conductive layer. The heat conductive layer may be a heat conductive layer including the above-mentioned heat conductive multilayer sheet.
Since the heat conductive material obtained by using the composition of the present invention has sufficient heat conductivity and high heat resistance, it is used for various electric devices such as personal computers, general household appliances, and automobiles. It is suitable for heat dissipation of power semiconductor devices.
Further, since the heat conductive material obtained by using the composition of the present invention has sufficient heat conductivity even in a semi-cured state, it reaches light for photocuring such as gaps between members of various devices. It can also be used as a heat radiating material to be placed in a part that is difficult to make. In addition, since it has excellent adhesiveness, it can be used as an adhesive having thermal conductivity.

Hereinafter, the present invention will be described in more detail with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention should not be construed as limiting by the examples shown below.

[Examples 1 to 40 and Comparative Examples 1 to 12 (preparation of composition)]
[Various ingredients]
The various components used in Examples and Comparative Examples are shown below.
<Specific compounds and comparative compounds>
The specific compounds used in the examples are shown below. The following C-1 to C-11 are specific compounds, and D-1 to D-2 are compounds that do not correspond to specific compounds (comparative compounds).

<Phenol compound>
The phenolic compounds A-1 to A-3 used in the examples are shown below.
The phenol compound A-1 used in the examples was synthesized with reference to US Pat. No. 4,992,596.

<Epoxy compound>
The epoxy compounds used in Examples and Comparative Examples are shown below. The following C-11 is a specific compound, and B-1 to B-3 are compounds that do not correspond to a specific compound.
B-2 below is a mixture of two types of epoxy compounds (trade name: Epototo ZX-1059, manufactured by Toto Kasei Co., Ltd.).

<Inorganic substances (inorganic nitrides and other inorganic substances)>
The inorganic substances used in Examples and Comparative Examples are shown below.
"AA-3": Aluminum oxide (average particle size: 3 μm, manufactured by Sumitomo Chemical)
"AA-04": Aluminum oxide (average particle size: 0.4 μm, manufactured by Sumitomo Chemical Co., Ltd.)
"HP-40 MF100": Aggregated boron nitride (average particle size: 40 μm, made of Mizushima alloy iron)
"SP-3": Scaly boron nitride (average particle size: 4 μm, manufactured by Denka Corporation)

<Curing accelerator>
_{PPh 3} (triphenylphosphine) was used as a curing accelerator.

<Solvent>
Cyclopentanone was used as the solvent.

<Dispersant>
DISPERBYK-106 (a polymer salt having an acidic group) was used as a dispersant.

<Surface modifier for aluminum oxide (organic silane molecule)>
The following compounds were used as surface modifiers for aluminum oxide.

[Examples 1 to 40 and Comparative Examples 1 to 12 (preparation of composition)]
A cured solution was prepared by blending the epoxy compounds and phenol compounds of the combinations shown in Tables 1 to 3 below in the addition amounts (g) shown in Tables 1 to 3 below.
After mixing the entire amount of the obtained curing liquid, the solvent, the dispersant, the surface modifier (surface modifier for aluminum oxide), and the curing accelerator in this order, an inorganic substance (inorganic nitride, inorganic oxide) was added. .. The obtained mixture was treated with a rotating revolution mixer (manufactured by THINKY, Awatori Rentaro ARE-310) for 5 minutes to obtain a composition (composition for forming a heat conductive material) of each Example or Comparative Example.
In Tables 1 to 3 below, for example, Examples 1 and 31 have similar compositions, but the methods for producing evaluation targets described later are different.

Here, the amount of the solvent added was set so that the solid content concentration of the composition was 50 to 80% by mass.
The solid content concentration of the composition was adjusted for each composition within the above range so that the viscosities of the compositions would be about the same.
The amount of the curing accelerator added was such that the content of the curing accelerator in the composition was 1% by mass with respect to the total content of the epoxy compound and the specific compound having an epoxy group.
The addition amount of the inorganic substance (total addition amount of the inorganic nitride and other inorganic substances) was the addition amount (g) shown in Tables 1 to 3 below.
Further, the inorganic substances were mixed and used so that the ratio (mass ratio) of the contents of each inorganic substance satisfied the relationships shown in Tables 1 to 3 below.
The amount of the dispersant added was such that the content of the dispersant in the composition was 0.2% by mass with respect to the content of the inorganic substance.
The amount of the surface modifier for aluminum oxide added is 0 when the content of the surface modifier for aluminum oxide in the composition is 0 with respect to the content of aluminum oxide (the total content of AA-3 and AA-04). The amount was set to be 2% by mass. If the composition does not contain aluminum oxide, no surface modifier for aluminum oxide is used.

[Manufacturing method A: Examples 1 to 15, 18 to 19, 22 to 25, 28 to 29 and Comparative Examples 1 to 2 (preparation of heat conductive sheet)]
<Making a heat conductive sheet>
Using an applicator, the prepared compositions shown in Tables 1 to 3 below were uniformly applied onto the release surface of the release-treated polyester film (NP-100A, manufactured by Panac Co., Ltd., film thickness 100 μm), and 120 The film was left at ° C. for 5 minutes to obtain a coating film.
Two such polyester films with a coating film are produced, and the two polyester films with a coating film are bonded to each other on the coating film surfaces, and then a flat plate is hot pressed under air (hot plate temperature 65 ° C., pressure 12 MPa). (Treatment for 1 minute) to obtain a semi-cured film.
The obtained semi-cured film was treated with a hot press under air (hot plate temperature 160 ° C., pressure 12 MPa for 20 minutes, and then further treated at normal pressure at 180 ° C. for 90 minutes) to cure the coating film, and the resin sheet was cured. Got The polyester films on both sides of the resin sheet were peeled off to obtain a heat conductive sheet having an average film thickness of 200 μm.

[Manufacturing method A: Examples 16 to 17, 20 to 21 and 26 to 27 (preparation of thermally conductive multilayer sheet)]
<Preparation of semi-cured film>
Using an applicator, the prepared compositions shown in Tables 1 to 3 below were uniformly applied onto the release surface of the release-treated polyester film (NP-100A, manufactured by Panac Co., Ltd., film thickness 100 μm), and 120 The film was left at ° C. for 5 minutes to obtain a coating film.
Two such polyester films with a coating film are produced, and the two polyester films with a coating film are bonded to each other on the coating film surfaces, and then a flat plate is hot pressed under air (hot plate temperature 65 ° C., pressure 12 MPa). (Treatment for 1 minute) to obtain a semi-cured film.

<Preparation of adhesive layer film 1 (epoxy adhesive layer, no filler)>
21.6 parts of B-3 as an epoxy resin, 13.3 parts of A-1 as a curing agent _{, 0.21 parts of PPh 3} (triphenylphosphine) as a curing accelerator, and 64.9 parts of cyclopentanone are mixed. The coating liquid for the adhesive layer was obtained.
Using an applicator, the prepared coating liquid for the adhesive layer was uniformly applied onto the release surface of the release-treated polyester film (NP-100A Panac Co., Ltd., film thickness 100 μm), and at 120 ° C. for 5 minutes. It was left to obtain a coating film. The film thickness of the adhesive layer was set to 5 μm.

<Preparation of adhesive layer film 2 (epoxy adhesive layer, with filler)>
21.6 parts of B-3 as an epoxy resin, 13.3 parts of A-1 as a curing agent _{, 0.21 parts of PPh 3} as a curing accelerator, 35 parts of alumina AA-04, and 100 parts of cyclopentanone. The mixture was mixed to obtain a coating liquid for an adhesive layer.
Using an applicator, the prepared coating liquid for the adhesive layer was uniformly applied onto the release surface of the release-treated polyester film (NP-100A Panac Co., Ltd., film thickness 100 μm), and at 120 ° C. for 5 minutes. It was left to obtain a coating film. The film thickness of the adhesive layer was set to 5 μm.

<Making a multi-layer sheet>
The release PETs installed on both sides of the semi-cured film prepared above are peeled off, and the adhesive layer film having the adhesive layers shown in Tables 1 to 3 below is applied so that the adhesive layer faces the semi-cured film. An adhesive layer was attached to the film using a laminator under the conditions of a temperature of 120 ° C., a pressure of 0.7 MPa, a degree of vacuum of ≦ 1 kPa, and a time of 15 seconds to obtain a multilayer sheet.

<Preparation of cured multi-layer sheet>
The obtained multilayer sheet was treated with a hot press under air (hot plate temperature 160 ° C., pressure 12 MPa for 20 minutes, and then further treated at normal pressure at 180 ° C. for 90 minutes) to cure the coating film, and the resin sheet was formed. Obtained. The polyester films on both sides of the resin sheet were peeled off to obtain a cured multilayer sheet (thermally conductive multilayer sheet) having an average film thickness of 200 μm.

[Manufacturing method B: Examples 31, 34 to 35 and Comparative Examples 3 to 5 (preparation of heat conductive sheet)]
<Making a heat conductive sheet>
Using an applicator, the prepared compositions shown in Tables 1 to 3 below were uniformly applied onto the release surface of the release-treated PET film (PET765501, manufactured by Lintec Corporation, film thickness 75 μm) at 120 ° C. The film was left for 4 minutes to obtain a coating film.
A new polyester film was further attached to the surface of the coating film with the release surface side facing each other. A semi-cured film was obtained by roll-pressing the coating film sandwiched between polyester films in air. At the time of roll pressing, the temperature of the film surface of the coating film was heated to 100 ° C., and the linear pressure was 544 N / cm.
The obtained semi-cured film was treated with a hot press under air (hot plate temperature 160 ° C., pressure 12 MPa for 20 minutes, and then further treated at normal pressure at 180 ° C. for 90 minutes) to cure the coating film, and the resin sheet was cured. Got The polyester films on both sides of the resin sheet were peeled off to obtain a heat conductive sheet having an average film thickness of 200 μm.

[Manufacturing Method B: Examples 32 to 33 and Comparative Examples 6 to 7 (Preparation of thermally conductive multilayer sheet)]
A cured multilayer sheet (heat conductive multilayer sheet) was obtained in the same manner as in Example 16 except that the semi-cured film prepared by the following method was used.
<Preparation of semi-cured film>
Using an applicator, the prepared compositions shown in Tables 1 to 3 below were uniformly applied onto the release surface of the release-treated PET film (PET765501, manufactured by Lintec Corporation, film thickness 75 μm) at 120 ° C. The film was left for 4 minutes to obtain a coating film.
A new polyester film was further attached to the surface of the coating film with the release surface side facing each other. A semi-cured film was obtained by roll-pressing the coating film sandwiched between polyester films in air. At the time of roll pressing, the temperature of the film surface of the coating film was heated to 100 ° C., and the linear pressure was 544 N / cm.

[Manufacturing method C: Examples 36, 39 to 40 and Comparative Examples 8 to 10 (preparation of heat conductive sheet)]
<Making a heat conductive sheet>
Using an applicator, the prepared compositions shown in Tables 1 to 3 below were uniformly applied onto the release surface of the release-treated PET film (PET765501, manufactured by Lintec Corporation, film thickness 75 μm) at 120 ° C. After heating for 4 minutes at 80 ° C., a semi-cured film was obtained by further heating at 80 ° C. for 2 minutes.
The obtained semi-cured film was treated with a hot press under air (hot plate temperature 160 ° C., pressure 12 MPa for 20 minutes, and then further treated at normal pressure at 180 ° C. for 90 minutes) to cure the coating film, and the resin sheet was cured. Got The polyester films on both sides of the resin sheet were peeled off to obtain a heat conductive sheet having an average film thickness of 200 μm.

[Manufacturing Method C: Examples 37 to 38 and Comparative Examples 11 to 12 (Preparation of thermally conductive multilayer sheet)]
A cured multilayer sheet (heat conductive multilayer sheet) was obtained in the same manner as in Example 16 except that the semi-cured film prepared by the following method was used.
<Preparation of semi-cured film>
Using an applicator, the prepared compositions shown in Tables 1 to 3 below were uniformly applied onto the release surface of the release-treated PET film (PET765501, manufactured by Lintec Corporation, film thickness 75 μm) at 120 ° C. After heating for 4 minutes at 80 ° C., a semi-cured film was obtained by further heating at 80 ° C. for 2 minutes.

[Examples 1 to 40 and Comparative Examples 1 to 12 (evaluation of heat conductive sheet and heat conductive multilayer sheet)]
<Thermal conductivity>
The thermal conductivity evaluation was carried out using each thermal conductive sheet and the thermally conductive multilayer sheet obtained by using each composition. The thermal conductivity was measured by the following method, and the thermal conductivity was evaluated according to the following criteria.

(Measurement of thermal conductivity (W / m · k))
(1) Using "LFA467" manufactured by NETZSCH, the thermal diffusivity in the thickness direction of the heat conductive sheet was measured by a laser flash method.
(2) The specific gravity of the heat conductive sheet was measured by the Archimedes method (using the "solid specific gravity measurement kit") using the balance "XS204" manufactured by METTLER TOLEDO.
(3) Using "DSC320 / 6200" manufactured by Seiko Instruments Inc., the specific heat of the heat conductive sheet at 25 ° C. was determined under the heating condition of 10 ° C./min.
(4) The obtained thermal diffusivity was multiplied by the specific gravity and the specific heat to calculate the thermal conductivity of the heat conductive sheet.

(Evaluation criteria)
The measured thermal conductivity was classified according to the following criteria and used as an evaluation of thermal conductivity.
"A": 17 W / m · K or more "B": 13 W / m · K or more and less than 17 W / m · K "C": 10 W / m · K or more and less than 13 W / m · K "D": 10 W / m · K The results of less than K are shown in Tables 1 to 3 below.

<Water resistance>
Water resistance evaluation was carried out using each heat conductive sheet and heat conductive multilayer sheet obtained by using each composition. The water content was measured by the following method, and the water resistance was evaluated according to the following criteria.

(Measurement of water resistance)
The cured heat conductive sheet was exposed to a wet heat condition of 85 ° C. and 85% for 48 hours, and the water content was calculated from the change in the weight of the sheet before and after.
"A": less than 0.6% "B": 0.6% or more and less than 0.8% "C": 0.8% or more and less than 1.0% "D": 1.0% or more The results are shown in the table below. 1 to 3 are shown.

[result]
Below, Tables 1 to 3 below show the types and amounts (g) of phenol compounds, epoxy compounds, inorganic substances, curing accelerators, adhesive layers, and dispersants used in each heat conductive sheet and heat conductive multilayer sheet. The evaluation result is shown together with the amount (g).

From the results shown in Tables 1 to 3 above, it was confirmed that the composition of the present invention can be used to obtain a heat conductive sheet and a heat conductive multilayer sheet having excellent heat conductivity. Further, it was confirmed that the heat conductive sheet and the heat conductive multilayer sheet obtained by using the composition are excellent in water resistance.
Further, regardless of whether the semi-cured film is produced by using a press such as a flat plate press or a roll press, or when the semi-cured film is produced without using a press, the heat conductive material formed from the composition of the present invention is the present invention. It was confirmed that the effect of the invention can be realized.

It was confirmed that the obtained heat conductive sheet was more excellent in heat conductivity under the condition that L of the specific compound was "a divalent organic group having a divalent aromatic ring group" (Examples 1 to 6). Comparison of 9 to 10 with Examples 7 and 8).

When the Hansen solubility parameter of the specific compound was 28 or less, it was confirmed that the obtained heat conductive sheet and heat conductive multilayer sheet had excellent water resistance (Examples 1 to 30, Comparative Example 2 and Comparative Example 1). comparison).
Further, it was confirmed that the obtained heat conductive sheet and heat conductive multilayer sheet are more excellent in water resistance when the Hansen solubility parameter of the specific compound is 26 or less (Examples 1, 3 to 6, 8, 13 to 15). And Comparative Example 1 and Examples 2, 7, 9 to 12, 16 to 30 and Comparative Example 2).

It was confirmed that the heat conductive sheet was more excellent in heat conductivity under the condition that the composition of the inorganic substance contained in the heat conductive sheet was 75% by mass or more of boron nitride (comparison between Examples 18 to 19 and Examples 22 to 23).
Further, it was confirmed that the heat conductivity was superior to the heat conductivity under the condition that the composition of the inorganic substance contained in the heat conductive multilayer sheet was 80% by mass or more of boron nitride (comparison between Examples 16 to 17 and Examples 20 to 21). ).

Claims

A composition for forming a heat conductive material, which comprises inorganic particles and a compound represented by the general formula (1).

In the general formula (1),
E 1 to E 6 independently represent a single bond, -NH-, or -NR-. R represents a substituent.
B 1 , B 2 , B 3 and B 4 represent k + 1 valent, l + 1 valent, m + 1 valent and n + 1 valent organic groups, respectively, and at least one of them may have a substituent k + 1. Represents a valent, l + 1 valent, m + 1 valent, or n + 1 valent aromatic ring group.
L represents a divalent organic group.
k, l, m, and n each independently represent an integer of 0 or more.
when k is 2 or more, X 1 to the k present, may each be the same or different.
when l is 2 or more, X 2 of the l present, may each be the same or different.
when m is 2 or more, X 3 and m pieces present, may each be the same or different.
when n is 2 or more, X 4 n number present, may each be the same or different.
Further, the total of k, l, m, and n is 2 or more.
Each of X 1 to X 4 independently represents a group represented by the general formula (2).

In the general formula (2), * represents a bonding position.
D 1 represents a single bond or a divalent linking group.
A 1 represents an aromatic ring group which may have a substituent or an aliphatic ring group which may have a substituent.
Q and Y 1 are independently selected from the group consisting of a monovalent group having a hydroxyl group and an epoxy group, an amino group, a thiol group, a carboxylic acid group, an isocyanate group, and a monovalent group having an oxetanyl group. Represents a specific functional group.
p represents an integer greater than or equal to 0.
q represents an integer of 0 to 2.
In the general formula (2), if D 1 there are a plurality, D 1 there are a plurality, may each be the same or different. If the A 1 there are plural, A 1 there are a plurality, they may each be the same or different. When there are a plurality of Qs, the plurality of Qs may be the same or different.
r is an integer of 1 or more.
L in the general formula (1) is a divalent aromatic ring group which may have a substituent, a divalent aliphatic ring group which may have a substituent, and 2 or more carbon atoms. The composition for forming a heat conductive material according to claim 1, which is a divalent organic group having at least one selected from the group consisting of alkylene groups which may have a branch of.
The composition for forming a heat conductive material according to claim 1 or 2, wherein L in the general formula (1) is a divalent organic group having a divalent aromatic ring group which may have a substituent. thing.
The composition for forming a heat conductive material according to any one of claims 1 to 3, wherein the Hansen solubility parameter value of the compound represented by the general formula (1) is 28 MPa 0.5 or less.
The composition for forming a heat conductive material according to any one of claims 1 to 4, wherein the Hansen solubility parameter value of the compound represented by the general formula (1) is 26 MPa 0.5 or less.
The composition for forming a heat conductive material according to any one of claims 1 to 5, further comprising a curing accelerator.
The composition for forming a heat conductive material according to any one of claims 1 to 6, wherein the inorganic particles are inorganic nitrides.
The composition for forming a heat conductive material according to any one of claims 1 to 7, wherein the inorganic particles are boron nitride.
According to any one of claims 1 to 8, the content of the compound represented by the general formula (1) is 3 to 40% by mass with respect to the total solid content of the composition for forming a heat conductive material. The composition for forming a heat conductive material according to the above.
A heat conductive sheet formed by curing the composition for forming a heat conductive material according to any one of claims 1 to 9.
The heat conductive sheet according to claim 10,
A heat conductive multilayer sheet having an adhesive layer or an adhesive layer provided on one side or both sides of the heat conductive sheet.
With the device
A device with a heat conductive layer having a heat conductive sheet according to claim 10 or a heat conductive layer including the heat conductive multilayer sheet according to claim 11 arranged on the device.