Curable compositions, thermal conductive materials, thermal conductive sheets, devices with thermal conductive layers, compounds

Abstract

To provide a curable composition capable of forming a thermally conductive material excellent in thermal conductivity and also excellent in peel strength from an adherend, and to provide a thermally conductive material, a thermally conductive sheet, a device with a thermally conductive layer, and a compound which are related to the curable composition.SOLUTION: The curable composition contains a curable compound and inorganic particles. The inorganic particles are selected from the group consisting of inorganic nitride particles and inorganic oxide particles. The curable composition satisfies at least one of a requirement 1 (the inorganic particles are surface-modified with a compound having one or more acid anhydride groups and two or more alkoxysilyl groups), a requirement 2 (the curable composition contains a compound having one or more acid anhydride groups and two or more alkoxysilyl groups), a requirement 3 (the inorganic particles are surface-modified with a specific nitrogen-containing heterocycle), and a requirement 4 (the curable composition contains a specific nitrogen-containing heterocycle).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to curable compositions, thermal conductive materials, thermal conductive sheets, devices with thermal conductive layers, and compounds. [Background technology]

[0002] Power semiconductor devices, used in various electrical equipment such as personal computers, home appliances, and automobiles, have been rapidly miniaturized in recent years. This miniaturization has made it difficult to control the heat generated by these high-density power semiconductor devices. To address these issues, thermal conductive materials are used to promote heat dissipation from power semiconductor devices. For example, Patent Document 1 discloses a curable composition for forming a heat-conducting material that includes a specific spherical boron nitride fine powder. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2018 / 074077 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] In thermal conductive materials formed using curable compositions, high thermal conductivity is required. Furthermore, it is also required that the heat-conducting material formed using the curable composition exhibits excellent peel strength when bonded to an object (hereinafter also referred to as the "adhered object," for example, metal).

[0005] When the present inventors examined the curable composition described in Patent Document 1, they found that it is difficult to achieve both high thermal conductivity and high peel strength in the curable composition using the silane coupling agent described in Patent Document 1.

[0006] Therefore, the object of the present invention is to provide a curable composition that can form a thermally conductive material that has excellent thermal conductivity and excellent peel strength with respect to the adherend. Furthermore, the present invention also aims to provide thermal conductive materials, thermal conductive sheets, devices with thermal conductive layers, and compounds related to the above-mentioned curable composition. [Means for solving the problem]

[0007] The inventors of this invention have diligently studied and developed this invention to solve the above problems. In other words, they have found that the above problems can be solved by the following configuration.

[0008] [1] A curable composition comprising a curable compound and inorganic particles, The inorganic particles mentioned above are selected from the group consisting of inorganic nitride particles and inorganic oxide particles. A curable composition that satisfies at least one of the requirements 1 to 4 described below. [2] The curable composition according to [1], wherein the compound having one or more acid anhydride groups and two or more alkoxysilyl groups has a group represented by formula (x-1) described later. [3] The curable composition according to [1] or [2], wherein the compound having one or more acid anhydride groups and two or more alkoxysilyl groups has a repeating unit represented by any of the following formulas (x-2) to (x-4). [4] The curable composition according to any one of [1] to [3], wherein the inorganic particles are boron nitride particles or aggregates thereof. [5] Furthermore, a curable composition according to any one of [1] to [4], comprising an epoxy compound. [6] Furthermore, a curable composition according to any one of [1] to [5], comprising a phenol compound. [7] The above curable compound includes an epoxy compound and a phenol compound. The curable composition according to any one of [1] to [6], wherein the phenol compound has 3 to 7 hydroxyl groups in its molecule. [8] The above curable compound includes an epoxy compound and a phenol compound. A curable composition according to any one of [1] to [7], wherein the epoxy compound has a triazine skeleton, and the phenol compound has a triazine skeleton, at least one of these requirements. [9] Furthermore, a curable composition according to any one of [1] to [8], comprising a curing accelerator.

[10] The curable composition according to [9], wherein the curing accelerator comprises a compound containing a phosphorus atom.

[11] A thermal conductive material obtained by curing a curable composition described in any one of [1] to

[10] .

[12] A thermal conductive sheet made of the thermal conductive material described in

[11] .

[13] A device with a thermal conductive layer, comprising a device and a thermal conductive layer including a thermal conductive sheet described in

[12] disposed on the device.

[14] A compound represented by formula (X-1), which will be described later.

[15] A compound represented by formula (Y-1), which will be described later. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a curable composition that can form a thermally conductive material that has excellent thermal conductivity and excellent peel strength with respect to the adherend. Furthermore, according to the present invention, thermal conductive materials, thermal conductive sheets, devices with thermal conductive layers, and compounds related to the above-mentioned curable composition can also be provided. [Modes for carrying out the invention]

[0010] The present invention will be described in detail below. The following description of the constituent elements may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.

[0011] The following is a definition of each term used in this specification. In this specification, a numerical range represented by "~" means a range that includes the numbers written before and after "~" as the lower and upper limits, respectively.

[0012] In this specification, the number-average molecular weight and weight-average molecular weight are weight-average molecular weights obtained by gel permeation chromatography (GPC) on a polystyrene basis.

[0013] In this specification, "solids" refers to the components that form the thermal conductive material and does not include solvents. The components that form the thermal conductive material may also be components whose chemical structure changes through reaction (polymerization) during the formation of the thermal conductive material. Furthermore, any component that forms the thermal conductive material is considered a solid, even if its state is liquid.

[0014] In this specification, "(meth)acrylamide" means "either acrylamide or methacrylamide, or both." "(meth)acrylic" means "either acrylic or methacrylic, or both."

[0015] In this specification, the acid anhydride group may be either a monovalent or a divalent group. When the acid anhydride group is a monovalent group, examples include groups formed by removing one arbitrary hydrogen atom from acid anhydrides such as maleic anhydride, phthalic anhydride, pyromellitic anhydride, and trimellitic anhydride. When the acid anhydride group is a divalent group, it refers to a group represented as *-CO-O-CO-*, where * represents the bond position.

[0016] In this specification, substituents that are not explicitly stated as substituted or unsubstituted may, where possible, have further substituents (for example, substituent group Y described later) on their base, to the extent that they do not impair the desired effect. For example, the notation "alkyl group" means a substituted or unsubstituted alkyl group (an alkyl group that may have substituents) to the extent that it does not impair the desired effect. Furthermore, in this specification, the type of substituent, the position of the substituent, and the number of substituents are not particularly limited when it is stated that a substituent "may have substituents." For example, the number of substituents may be one or two or more. Examples of substituents include monovalent nonmetallic atom groups excluding hydrogen atoms, and groups selected from the following substituent group Y are preferred. In this specification, examples of halogen atoms include chlorine atoms, fluorine atoms, bromine atoms, and iodine atoms.

[0017] Substituent group Y: Halogen atoms (e.g., -F, -Br, -Cl, and -I), hydroxyl groups, amino groups, carboxylic acid groups and their conjugate base groups, carboxylic anhydride groups, cyanate ester groups, unsaturated polymerizable groups, epoxy groups, oxetanyl groups, azilidinyl groups, thiol groups, isocyanate groups, thioisocyanate groups, aldehyde groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, alkyldithio groups, aryldithio groups, N-alkylamino groups, N,N-dialkylamino groups, N-arylamino groups, N,N-diarylamino groups, N-alkyl-N-aryl Calcium amino 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-arylacylamino group, ureido group, N'-alkylureido group, N',N'-dialkylureido group, N'-arylureido group, N',N'-diarylureido group Id group, N'-alkyl-N'-arylureid group, N-alkylureid group, N-arylureid group, N'-alkyl-N-alkylureid group, N'-alkyl-N-arylureid group, N',N'-dialkyl-N-alkylureid group, N',N'-dialkyl-N-arylureid group, N'-aryl-N-arylureid group, N',N'-diaryl-N-alkylureid group, N',N'-diaryl-N-arylureid group, N'-alkyl-N'-aryl-N-alkylureid group do group, N'-alkyl-N'-aryl-N-arylureido group, alkoxycarbonylamino 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-diarylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfo group (-SO3H) and its conjugate base group, alkoxysulfonyl group, aryloxysulfonyl group, sulfinamoyl group, N-alkylsulfinamoyl group, N,N-dialkylsulfinamoyl group, N-alkyl-N-arylsulfinamoyl group, sulfamoyl group, N-alkylsulfamoyl group, N,N-dialkylsulfamoyl group, N-arylsulfamoyl group, N,N-diarylsulfamoyl group, N-alkyl-N-arylsulfamoyl group, N-acylsulfamoyl group and its conjugate base group, N-alkylsulfonylsulfamoyl group (-SO2NHSO2(alkyl)) and its conjugate base group, N-arylsulfonylsulfamoyl group (-SO2NHSO2(aryl)) and its conjugate base group, N-alkylsulfonylcarbamoyl group (-CONHSO2(alkyl)) and its conjugate base group, N-arylsulfonylcarbamoyl group (-CONHSO2(aryl)) and its conjugate base group, alkoxysilyl group (-Si(Oalkyl)3), aryloxysilyl group (-Si(Oaryl)3), hydroxysilyl group (-Si(OH)3) and its conjugate base group, phosphono group (-PO3H2) and its conjugate base group, dialkylphosphono group (-PO3(alkyl) )2) diarylphosphono group (-PO3(aryl)2), alkylarylphosphono group (-PO3(alkyl)(aryl)), monoalkylphosphono group (-PO3H(alkyl)) and its conjugate base group, monoarylphosphono group (-PO3H(aryl)) and its conjugate base group, phosphonooxy group (-OPO3H2) and its conjugate base group, dialkylphosphonooxy group (-OPO3(alkyl)2), diarylphosphonooxy group (-OPO3(aryl)2), alkylarylphosphonooxy group (-OPO3(alkyl)(aryl)), monoalkylphosphonooxy group (-OPO3H(alkyl)) and its conjugate base group, monoarylphosphonooxy group (-OPO3H(aryl)) and its conjugate base group, cyano group, nitro group, aryl group, alkenyl group, alkynyl group, and alkyl group. Furthermore, each of the above groups may have further substituents (for example, one or more of the above groups) if possible. For example, aryl groups that may have substituents are also included as selectable groups from substituent group Y. If a group selected from substituent group Y has carbon atoms, the number of carbon atoms in the group is, for example, 1 to 20. The number of atoms other than hydrogen atoms in a group selected from substituent group Y is, for example, 1 to 30. Furthermore, these substituents may or may not bond to each other or to the substituted group to form a ring, if possible. For example, the alkyl group (or the alkyl group portion in a group that includes an alkyl group as a substructure, such as an alkoxy group) may be a cyclic alkyl group (cycloalkyl group), or an alkyl group having one or more cyclic structures as substructures.

[0018] <Curable composition> The curable composition of the present invention is a curable composition comprising a curable compound and inorganic particles, wherein the inorganic particles are selected from the group consisting of inorganic nitride particles and inorganic oxide particles. At least one of requirements 1-4 must be met. The curable composition preferably satisfies at least one of requirement 1 and requirement 2, or at least one of requirement 3 and requirement 4, and more preferably satisfies requirement 1 or requirement 3.

[0019] Requirement 1: The inorganic particles are surface-modified with at least one selected from the group consisting of compounds having one or more acid anhydride groups and two or more alkoxysilyl groups, their hydrolysates, and their hydrolysate condensates. Requirement 2: The curable composition contains at least one selected from the group consisting of compounds having one or more acid anhydride groups and two or more alkoxysilyl groups, their hydrolysates, and their hydrolysate condensates. Requirement 3: The inorganic particles are surface-modified with at least one compound selected from the group consisting of a pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyridazine ring, pyrazine ring, pyrimidine ring, triazole ring, tetrazole ring, isoindole ring, indole ring, benzimidazole ring, indazole ring, benzotriazole ring, imidazopyridine ring, purine ring and its derivatives, pyrazolopyrimidine ring, triazolopyrimidine ring, benzothiazole ring, furan ring and thiophene ring, a compound having one or more aromatic heterocycles and one or more alkoxysilyl groups, hydrolysates thereof, and hydrolysis condensates thereof. Requirement 4: The curable composition contains at least one compound selected from the group consisting of a pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyridazine ring, pyrazine ring, pyrimidine ring, triazole ring, tetrazole ring, isoindole ring, indole ring, benzimidazole ring, indazole ring, benzotriazole ring, imidazopyridine ring, purine ring and its derivatives, pyrazolopyrimidine ring, triazolopyrimidine ring, benzothiazole ring, furan ring and thiophene ring, having one or more aromatic heterocycles and one or more alkoxysilyl groups, hydrolysates thereof, and hydrolysis condensates thereof. Hereinafter, a compound having one or more acid anhydride groups and two or more alkoxysilyl groups will also be referred to as "compound X". Furthermore, at least one compound selected from the group consisting of compound X, hydrolysates of compound X, and hydrolyzed condensates of compound X will also be referred to as "compound X, etc." Compounds having one or more aromatic heterocycles selected from the group consisting of a pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyridazine ring, pyrazine ring, pyrimidine ring, triazole ring, tetrazole ring, isoindole ring, indole ring, benzimidazole ring, indazole ring, benzotriazole ring, imidazopyridine ring, purine ring and its derivatives, pyrazolopyrimidine ring, triazolopyrimidine ring, benzothiazole ring, furan ring, and thiophene ring (hereinafter also referred to as "specific aromatic heterocycles") and one or more alkoxysilyl groups are also called "compound Y". Furthermore, at least one compound selected from the group consisting of compound Y, hydrolysates of compound Y, and hydrolyzed condensates of compound Y is also called "compound Y, etc."

[0020] The mechanism by which the curable composition of the present invention can form a thermally conductive material with excellent thermal conductivity and peel strength from the adherend is not entirely clear, but the inventors speculate as follows. The curable composition of the present invention satisfies at least one of the above requirements 1 to 4. In both cases where the curable composition satisfies requirement 1 and requirement 4, the alkoxysilyl group and the group produced by the hydrolysis of the alkoxysilyl group in compound X or compound Y are considered to readily form bonds with the surface of inorganic particles and / or to have strong interactions with the surface of inorganic particles. Therefore, the surface of inorganic particles is easily modified by compound X or compound Y. Furthermore, in both cases where the curable composition satisfies requirement 2 and requirement 4, the alkoxysilyl groups of compound X or compound Y and the groups produced by the hydrolysis of the alkoxysilyl groups are likely to be positioned close to the surface of the inorganic particles in the curable composition. This arrangement allows the inorganic particles to be included in the curable composition without impairing the thermal conductivity of the inorganic particles, and the resulting thermal conductive material is expected to have excellent thermal conductivity. In addition, the acid anhydride groups and specific aromatic heterocycles enhance the adhesion between the formed thermal conductive material and the adherend, and can alleviate stress generated during curing. As a result, the formed thermal conductive material is expected to have excellent peel strength.

[0021] The following details the components that may be included in the curable composition. Furthermore, the fact that a heat-conducting material formed by a curable composition has excellent thermal conductivity is simply referred to as "having excellent thermal conductivity." Also, the fact that a heat-conducting material formed by a curable composition has excellent peel strength with respect to the adherend is simply referred to as "having excellent peel strength."

[0022] [Curable compound] The curable composition of the present invention comprises a curable compound. A curable compound is a compound different from the above-mentioned compound X, etc. and compound Y, etc. Examples of curable compounds include phenol compounds, epoxy compounds, and maleimide compounds. It is also preferable that the curable compound does not have silicon atoms or groups containing silicon atoms.

[0023] (Phenol compounds) A phenolic compound is a compound having one or more phenolic hydroxyl groups (preferably two or more, more preferably 2 to 10).

[0024] The phenolic compound is preferably a compound represented by formula (Z).

[0025]

Chemical formula

[0026] In formula (Z), when there are a plurality of groups represented by the same symbol, unless otherwise specified, the plurality of groups represented by the same symbol may be the same or different from each other.

[0027] In formula (Z), E 1 ~E 6 each independently represents a single bond, -NH-, or -NR-. R represents a substituent. Examples of the above-mentioned substituent include a linear or branched alkyl group having 1 to 5 carbon atoms. E 1 ~E 6 each independently is preferably -NH- or -NR-, and more preferably -NH-.

[0028] In formula (Z), B 1 represents a single bond or a (k + 1)-valent organic group. B 2 represents a single bond or a (l + 1)-valent organic group. B 3 represents a single bond or a (m + 1)-valent organic group. B 4 represents a single bond or a (n + 1)-valent organic group. The values of k, l, m, and n in the above-mentioned (k + 1)-valent organic group, the above-mentioned (l + 1)-valent organic group, the above-mentioned (m + 1)-valent organic group, and the above-mentioned (n + 1)-valent organic group are consistent with the values of k, l, m, and n explicitly shown in formula (Z). In addition, when r is 2 or more and the values of a plurality of m are different, the value of m in the (m + 1)-valent organic group represented by B 3 is the m value of the B 3 bonded to X3 This is the same as the value of m, which indicates the number of [something].

[0029] B 1 ~B 4 Examples of organic groups represented by include groups obtained by removing j hydrogen atoms from a hydrocarbon which may have heteroatoms with 1 to 20 carbon atoms. Hereinafter, j atoms refers to k+1, l+1, m+1, or n+1 atoms. Here, the hydrocarbon before removing j hydrogen atoms can be, for example, one or more hydrocarbons selected from the group consisting of aliphatic hydrocarbons having 1 to 20 carbon atoms that may have substituents, aliphatic rings having 3 to 20 carbon atoms that may have substituents, and aromatic rings having 3 to 20 carbon atoms that may have substituents. Furthermore, for the above one or more hydrocarbons, -O-, -S-, -CO-, -NR N -(R N represents a hydrogen atom or substituent. A combination of one or more divalent linking groups selected from the group consisting of ) and -SO2- may also be used. Examples of aliphatic hydrocarbons having 1 to 20 carbon atoms include methane, ethane, propane, butane, pentane, hexane, and heptane. Examples of aliphatic rings having 3 to 20 carbon atoms include cyclohexane rings, cycloheptane rings, norbornane rings, and adamantane rings. Examples of aromatic rings having 3 to 20 carbon atoms include aromatic hydrocarbon rings having 6 to 20 carbon atoms and aromatic heterocycles having 3 to 20 carbon atoms. Examples of aromatic hydrocarbon rings having 6 to 20 carbon atoms include benzene rings, naphthalene rings, and anthracene rings. Examples of aromatic heterocycles having 3 to 20 carbon atoms include furan rings, pyrrole rings, thiophene rings, pyridine rings, thiazole rings, carbazole rings, indole rings, and benzothiazole rings.

[0030] In formula (Z), k, l, m, and n each independently represent an integer of 0 or greater. However, the sum of k, l, r × m, and n is an integer of 2 or greater, preferably an integer between 2 and 12, and more preferably an integer between 4 and 8. Note that the value of m in "r × m" is the average of any multiple possible values ​​of m. k, l, m, and n are each independently preferably integers between 0 and 5, and more preferably integers between 1 and 2. For example, it is preferable that k is an integer greater than or equal to 1 (for example, an integer between 1 and 2), l is an integer greater than or equal to 1 (for example, an integer between 1 and 2), m is an integer greater than or equal to 1 (for example, an integer between 1 and 2), and n is an integer greater than or equal to 1 (for example, an integer between 1 and 2). Note that if k is 0, B 1 is X 1 It does not have. If l is 0, B 2 is X 2 It does not have. If m is 0, B 3 is X 3 It does not have. If n is 0, B 4 is X 4 It does not possess. Also, B 1 If it is a single bond, then k is 1. 2 If it is a single bond, then l is 1. 3 If it is a single bond, then m is 1. 4 If it is a single bond, then n is 1.

[0031] L represents a divalent organic group. Examples of divalent organic groups include optionally substituted divalent aromatic ring groups, optionally substituted divalent aliphatic hydrocarbon groups, optionally substituted divalent aliphatic ring groups, and -N(R NA Examples include -, -CO- and combinations thereof. NA The group represented is an organic group. The groups exemplified above as divalent organic groups are further -O-, -S-, and -N(R N )- and may have groups that combine these. R N R represents a substituent. N Examples of substituents represented by include linear or branched alkyl groups having 1 to 5 carbon atoms. Furthermore, examples of substituents that the above aromatic ring group, the above aliphatic hydrocarbon group, and the above aliphatic ring group may have include linear or branched alkyl groups having 1 to 5 carbon atoms.

[0032] Examples of divalent aromatic ring groups include divalent aromatic hydrocarbon groups having 6 to 20 carbon atoms and divalent aromatic heterocyclic groups having 3 to 20 carbon atoms. Examples of aromatic rings constituting divalent aromatic hydrocarbon groups having 6 to 20 carbon atoms include monocyclic aromatic rings such as benzene rings; and polycyclic aromatic ring groups such as naphthalene rings and anthracene rings. Examples of aromatic heterocycles constituting divalent aromatic heterocyclic groups having 3 to 20 carbon atoms include monocyclic aromatic heterocycles such as furan rings, pyrrole rings, thiophene rings, pyridine rings, and thiazole rings; and polycyclic aromatic heterocycles such as benzothiazole rings, carbazole rings, and indole rings. Furthermore, a divalent aromatic ring group as L can be defined as the group obtained by removing two hydrogen atoms from the above example.

[0033] Examples of divalent aliphatic hydrocarbon groups include alkylene groups having 1 to 12 carbon atoms, specifically methylene, ethylene, propylene, butylene, pentylene, hexylene, methylhexylene, and heptylene groups.

[0034] Examples of aliphatic rings that constitute a divalent aliphatic ring group include cyclohexane rings, cycloheptane rings, norbornane rings, and adamantane rings. Furthermore, an aliphatic ring group as L can be defined as the group obtained by removing two hydrogen atoms from the example above.

[0035] A substituted divalent aromatic ring group, a substituted divalent aliphatic hydrocarbon group, a substituted divalent aliphatic ring group, or -O-, -S-, -NR N The groups combining - or -CO- may include divalent linking groups consisting of two or more of these combinations, and divalent linking groups in which two or more groups of the same type (e.g., aromatic ring groups) are combined via single bonds.

[0036] In this invention, it is preferable that both ends of L are carbon atoms, as this provides superior thermal conductivity for the heat-conducting material. The terminal carbon atoms may also be part of a cyclic structure. Furthermore, in the present invention, in order to obtain better thermal conductivity of the heat-conducting material, it is preferable that L in formula (P2) above be a divalent organic group having at least one selected from the group consisting of a divalent aromatic ring group which may have substituents, a divalent aliphatic ring group which may have substituents, and an alkylene group which may have branching with 2 or more carbon atoms, and a divalent organic group having a divalent aromatic ring group which may have substituents is more preferable for the reason that it provides better thermal conductivity.

[0037] In equation (Z), r is a non-negative integer. r is preferably an integer between 0 and 20, and more preferably an integer between 0 and 10.

[0038] In formula (Z), X 1 ~X 4 Each of these independently represents an aromatic ring group having a phenolic hydroxyl group. The "aromatic ring group having a phenolic hydroxyl group" is any aromatic ring group having one or more hydroxyl groups (phenolic hydroxyl groups) directly bonded to the aromatic ring (for example, 1 to 4). The above aromatic ring group may or may not have substituents other than the above hydroxyl group. The above aromatic ring group may be monocyclic or polycyclic, and may have heteroatoms as ring member atoms. The number of ring member atoms of the above aromatic ring group is preferably 5 to 15, more preferably 6 to 10, and even more preferably 6. The above aromatic ring group is preferably a benzene ring group. The substituents that the above aromatic ring group may have other than the hydroxyl group are preferably substituents having 1 to 6 carbon atoms, more preferably hydrocarbon groups having 1 to 6 carbon atoms, and even more preferably linear or branched alkyl groups having 1 to 6 carbon atoms.

[0039] In equation (Z), there are k X 1 There are l X 2 There are r × m X 3 and n X4 It is also preferable that at least one of these is an aromatic ring group having a phenolic hydroxyl group and a substituent positioned at the ortho position of the phenolic hydroxyl group. The substituent may be present at only one or both ortho positions of the phenolic hydroxyl group. Note that the value of m in "r × m" is the average of any multiple possible values ​​of m. Furthermore, the "substituent positioned in the ortho position" is preferably a substituent having 1 to 6 carbon atoms, more preferably a hydrocarbon group having 1 to 6 carbon atoms, and even more preferably a linear or branched alkyl group having 1 to 6 carbon atoms. In other words, there are (k+l+r×m+n) X 1 ~X 4 Of the "aromatic ring groups having a phenolic hydroxyl group" represented by any of the above, at least one (preferably 30% or more, more preferably 50% or more, even more preferably 65% ​​or more; preferably 100% or less, more preferably 90% or less, even more preferably 80% or less) may represent an "aromatic ring group having a phenolic hydroxyl group and a substituent positioned at the ortho position of the phenolic hydroxyl group."

[0040] X 1 ~X 4 In an aromatic ring group having a phenolic hydroxyl group represented by , aromatic ring groups other than "an aromatic ring group having a phenolic hydroxyl group and a substituent positioned in the ortho position of the phenolic hydroxyl group" may or may not have substituents other than the hydroxyl group (phenolic hydroxyl group). Aromatic ring groups other than "aromatic ring groups having a phenolic hydroxyl group and a substituent positioned in the ortho position of the phenolic hydroxyl group" include, for example, the hydroxyphenyl group. There are (k+l+r×m+n) X 1 ~X 4 It is also preferable that at least one (for example, one or two) of the "aromatic ring groups having a phenolic hydroxyl group" represented by any of the above is an aromatic ring group other than "an aromatic ring group having a phenolic hydroxyl group and a substituent positioned at the ortho position of the phenolic hydroxyl group". X 1 ~X 4In aromatic ring groups having a phenolic hydroxyl group, as represented by , the presence of aromatic ring groups other than "aromatic ring groups having a phenolic hydroxyl group and a substituent positioned in the ortho position of the phenolic hydroxyl group" is thought to disrupt the overall symmetry of the compound, lower the melting point of the compound, and improve the handling properties of the semi-cured film formed from the curable composition.

[0041] The phenol compound is also preferably a compound represented by formula (Z1). The phenol compound preferably contains the compound represented by formula (Z1), and the phenol compound may be the compound represented by formula (Z1) itself. The content of the compound represented by formula (Z1) is preferably 10 to 100% by mass, more preferably 25 to 100% by mass, and even more preferably 50 to 100% by mass, relative to the total mass of the phenol compound.

[0042] [ka]

[0043] In equation (Z1), r represents an integer greater than or equal to 0. r is preferably an integer between 0 and 20, and more preferably an integer between 0 and 10. L represents a divalent organic group. The divalent organic group represented by L in formula (Z1) is similar to, for example, the divalent organic group represented by L in formula (Z1). R Z represents a hydrogen atom or substituent. R Z The substituents represented are preferably substituents having 1 to 6 carbon atoms, more preferably hydrocarbon groups having 1 to 6 carbon atoms, and even more preferably linear or branched alkyl groups having 1 to 6 carbon atoms. There are (3+r) R in equation (Z1). Z At least one of these (preferably 30% or more, more preferably 50% or more, even more preferably 65% ​​or more; preferably 90% or less, more preferably 80% or less) may represent a substituent. There are (3+r) R in equation (Z1). ZAt least one of them (for example, one or two) may represent a hydrogen atom. R in equation (Z1) z (preferably R is a substituent) z ) and in a benzene ring group to which OH is bonded, the above R z (preferably R is a substituent) z ) is also preferably located at the para position relative to the NH to which the benzene ring group is bonded.

[0044] The phenol compound is also preferably a compound represented by formula (Z2). The phenol compound preferably contains the compound represented by formula (Z2), and the phenol compound may be the compound represented by formula (Z2) itself. The content of the compound represented by formula (Z2) is preferably 10 to 100% by mass, more preferably 25 to 100% by mass, and even more preferably 50 to 100% by mass, relative to the total mass of the phenol compound.

[0045] [ka]

[0046] In formula (Z2), R Z represents a hydrogen atom or substituent. There are two R's. Z It is preferable that at least one of them represents a substituent, and it is also preferable that both represent substituents. R Z The substituents represented are preferably substituents having 1 to 6 carbon atoms, more preferably hydrocarbon groups having 1 to 6 carbon atoms, and even more preferably alkyl groups having 1 to 6 carbon atoms. The alkyl group may be linear or branched. It is also preferable that the alkyl group be unsubstituted. The two R's in equation (Z2) z These may be the same or different.

[0047] The phenol compound is also preferably a phenol compound having 3 to 7 hydroxyl groups in its molecule. Examples of phenol compounds having 3 to 7 hydroxyl groups in the above molecule include the compound represented by formula (Z3).

[0048] [ka]

[0049] In equation (Z3), m represents an integer between 1 and 6. m is more preferably an integer between 1 and 3, and even more preferably 1.

[0050] In equation (Z3), n1 and n2 each independently represent an integer greater than or equal to 1. n1 and n2 are each independently preferably integers between 2 and 4, and more preferably 2 or 3. The sum of n1, n2, and m is an integer between 3 and 7.

[0051] In formula (Z3), R 1 ~R 6 Each of these independently represents a hydrogen atom, a halogen atom, a carboxylic acid group, an alkyl group, an alkoxy group, or an alkoxycarbonyl group. The halogen atoms mentioned above are preferably chlorine atoms, fluorine atoms, bromine atoms, or iodine atoms, with chlorine atoms being more preferred. The alkyl group described above may be linear or branched, preferably has 1 to 10 carbon atoms, and may or may not have substituents. The alkyl group portion of the above alkoxy group and the alkyl group portion of the above alkoxycarbonyl group are the same as those of the above alkyl group. R 1 and R 6 In each case, a hydrogen atom or a halogen atom is preferred, a hydrogen atom or a chlorine atom is more preferred, and a hydrogen atom is even more preferred. R 2 ~R 5 In each case, a hydrogen atom is preferred. Note that in equation (Z3), R 4 If there are multiple instances, then there are multiple R 4These may be the same or different. 5 If there are multiple instances, then there are multiple R 5 These may be the same or different.

[0052] In formula (Z3), Q represents an alkyl group, a phenyl group, a halogen atom, a carboxylic acid group, an alkoxy group, or an alkoxycarbonyl group. The alkyl group described above may be linear or branched, preferably has 1 to 10 carbon atoms, and may or may not have substituents. The alkyl portion of the alkoxycarbonyl group and the alkyl portion of the alkoxycarbonyl group are the same as those of the alkyl group described above. The phenyl group described above may or may not have substituents. The halogen atom mentioned above is preferably a chlorine atom, a fluorine atom, a bromine atom, or an iodine atom. For Q, an alkyl group is preferred, and a methyl group is more preferred. Note that if there are multiple Qs in equation (Z3), the multiple Qs may be the same or different.

[0053] Examples of phenolic compounds include bisphenol A, F, S, AD, benzenediol or benzenetriol benzene polyols, biphenyl aralkyl type phenolic resins, phenol novolac resins, cresol novolac resins, aromatic hydrocarbon formaldehyde resin-modified phenolic resins, dicyclopentadienephenol addition type resins, phenol aralkyl resins, polyvalent phenol novolac resins synthesized from polyvalent hydroxy compounds and formaldehyde, naphthol aralkyl resins, trimethylol methane resins, tetraphenyloleethane resins, naphthol novolac resins, naphthol phenol co-condensed novolac resins, naphthol cresol co-condensed novolac resins, biphenyl-modified phenolic resins, biphenyl-modified naphthol resins, aminotriazine-modified phenolic resins, and alkoxy group-containing aromatic ring-modified novolac resins.

[0054] The molecular weight of the phenol compound is preferably 225 to 2,000, and more preferably 225 to 1,000. If the above molecular weight has a molecular weight distribution, then the above molecular weight is the weight-average molecular weight.

[0055] The hydroxyl group content of the phenol compound is preferably 2.0 mmol / g or more, and more preferably 4.0 mmol / g or more. The upper limit is preferably 25.0 mmol / g or less, and more preferably 10.0 mmol / g or less. The hydroxyl group content mentioned above refers to the number of hydroxyl groups (preferably phenolic hydroxyl groups) present in 1 g of the phenol compound. Furthermore, the phenol compound may or may not have active hydrogen-containing groups (e.g., carboxyl groups) that can polymerize with epoxy compounds, in addition to hydroxyl groups. The lower limit of the active hydrogen content of the phenol compound (total hydrogen atom content in hydroxyl groups and carboxylic acid groups, etc.) is preferably 2.0 mmol / g or more, and more preferably 4.0 mmol / g or more. The upper limit is preferably 25.0 mmol / g or less, and more preferably 10.0 mmol / g or less.

[0056] Furthermore, the curable composition of the present invention may also contain compounds having groups that can react with epoxy compounds (hereinafter also referred to as "other active hydrogen-containing compounds") in addition to phenol compounds. However, in the curable composition of the present invention, the mass ratio of the content of other active hydrogen-containing compounds to the content of phenol compounds is preferably 0 to 1, more preferably 0 to 0.1, and even more preferably 0 to 0.05.

[0057] In the curable composition, the content of the phenol compound is preferably 3 to 90% by mass, more preferably 5 to 50% by mass, and even more preferably 7 to 40% by mass, based on the total solid content of the curable composition.

[0058] (Epoxy compound) Epoxy compounds are compounds that have at least one epoxy group (oxyranyl group) in one molecule. The epoxy group described above is a group obtained by removing one or more hydrogen atoms (preferably one hydrogen atom) from an oxirane ring. The epoxy group may, if possible, have further substituents (for example, linear or branched alkyl groups having 1 to 5 carbon atoms).

[0059] The number of epoxy groups in an epoxy compound is preferably 2 or more, more preferably 2 to 1000, and even more preferably 2 to 40 per molecule.

[0060] The molecular weight of the epoxy compound is preferably 150 or more, and more preferably 300 or more. The upper limit is preferably 100,000 or less, and more preferably 10,000 or less. If the above molecular weight has a molecular weight distribution, then the above molecular weight is the weight-average molecular weight.

[0061] The epoxy group content of the epoxy compound is preferably 2.0 to 20.0 mmol / g, and more preferably 5.0 to 15.0 mmol / g. The epoxy group content mentioned above refers to the number of epoxy groups present in 1 gram of the epoxy compound. Epoxy compounds are also preferably found to have aromatic ring groups (preferably aromatic hydrocarbon ring groups). The content of the epoxy compound having an aromatic ring group is preferably 5 to 100% by mass, more preferably 50 to 100% by mass, and even more preferably 70 to 100% by mass, relative to the total mass of the epoxy compound.

[0062] The epoxy compound may or may not exhibit liquid crystalline properties. In other words, the epoxy compound may be a liquid crystal compound. To put it another way, it may be a liquid crystal compound having an epoxy group. Examples of epoxy compounds (which may be liquid crystalline epoxy compounds) include compounds containing at least a portion of a rod-like structure (rod-like compounds) and compounds containing at least a portion of a disc-like structure (disc-like compounds). The rod-shaped and disc-shaped compounds will be described in detail below.

[0063] -Rod-shaped compounds- Examples of rod-shaped epoxy compounds include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyanosubstituted phenylpyrimidines, alkoxysubstituted phenylpyrimidines, phenyldioxanes, trans, and alkenylcyclohexylbenzonitriles. The rod-shaped compound may be either a low-molecular-weight compound or a high-molecular-weight compound. The high-molecular-weight compound is a compound obtained by polymerizing a rod-shaped compound having a low-molecular-weight reactive group.

[0064] The rod-shaped compound is preferably a compound represented by formula (E1).

[0065] [ka]

[0066] In formula (E1), L E1 Each of these independently represents a single bond or a divalent linking group. L E1 A divalent linking group is preferred. The divalent linking group is preferably -O-, -S-, -CO-, -NH-, -CH=CH-, -C≡C-, -CH=N-, -N=CH-, -N=N-, an alkylene group which may have substitution properties, or a group consisting of two or more combinations thereof, with -O-alkylene group- or -alkylene group-O- being more preferred. The alkylene group may be linear, branched, or cyclic, with a linear alkylene group having 1 to 2 carbon atoms being preferred. Multiple L E1 These may be the same or different.

[0067] In formula (E1), L E2 These are independent single bonds, -CH=CH-, -CO-O-, -O-CO-, -C(-CH3)=CH-, -CH=C(-CH3)-, -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(-CN)-, or -C(-CN)=CH-. L E2 Each of these is preferably a single bond, -CO-O-, or -O-CO-. L E2 If there are multiple L E2 These may be the same or different.

[0068] In formula (E1), L E3 Each of these independently represents a five-membered or six-membered aromatic ring group, a five-membered or six-membered non-aromatic ring group, or a polycyclic group consisting of these rings, which may have single bonds or substituents. L E3 Examples of aromatic and non-aromatic ring groups represented by include 1,4-cyclohexanediyl group, 1,4-cyclohexendiyl group, 1,4-phenylene group, pyrimidine-2,5-diyl group, pyridine-2,5-diyl group, 1,3,4-thiadiazole-2,5-diyl group, 1,3,4-oxadiazole-2,5-diyl group, naphthalene-2,6-diyl group, naphthalene-1,5-diyl group, thiophene-2,5-diyl group, and pyridazine-3,6-diyl group, which may have substituents. In the case of the 1,4-cyclohexanediyl group, either the trans or cis structural isomer may be used, or a mixture in any proportion may be used. The trans isomer is preferred. L E3 The preferred components are a single bond, a 1,4-phenylene group, or a 1,4-cyclohexendiyl group. L E3 The substituents on the group represented by are 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 having 1 carbon atom). In addition, when there are a plurality of substituents, the substituents may be the same or different from each other. L E3 When there are a plurality of L E3 they may be the same or different from each other.

[0069] In formula (E1), pe represents an integer of 0 or more. When pe is an integer of 2 or more, a plurality of (-L E3 -L E2 -) may be the same or different from each other. pe is preferably an integer of 0 to 2, more preferably 0 or 1, and still more preferably 0.

[0070] In formula (E1), L E4 each 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, more preferably an alkyl group (preferably having 1 carbon atom). A plurality of L E4 may be the same or different from each other. Further, when le described below is an integer of 2 or more, a plurality of L E4 in the same (L le ) E4 [[ID=3may also be the same or different from each other.

[0071] In formula (E1), le each independently represents an integer of 0 to 4. le is preferably an integer of each independently 0 to 2. A plurality of le may be the same or different from each other.

[0072] In addition, in the compound represented by formula (E1), a compound in which one or both of the two "epoxy group - L E1 -" are replaced with a diglycidylaminoalkylene group (preferably a diglycidylaminomethylene group) is also preferable.

[0073] The rod-shaped compound is also preferable to have a biphenyl skeleton, as this results in superior thermal conductivity for the resulting heat-conducting material. In other words, the epoxy compound may also preferably have a biphenyl skeleton, and in this case, the epoxy compound is preferably a rod-shaped compound.

[0074] -Disc-shaped compound- Epoxy compounds, which are disc-shaped compounds, have at least partially disc-shaped structures. The disc-shaped structure has at least an alicyclic or aromatic ring. In particular, if the disc-shaped structure has an aromatic ring, the disc-shaped compound can form a columnar structure by the formation of a stacking structure due to intermolecular π-π interactions. Specifically, examples of disc-shaped structures include the triphenylene structure described in Angew. Chem. Int. Ed. 2012, 51, 7990-7993 or Japanese Patent Publication No. Hei 7-306317, and the trisubstituted benzene structures described in Japanese Patent Publication No. 2007-002220 and Japanese Patent Publication No. 2010-244038.

[0075] Using a disc-shaped compound as the epoxy compound can yield a thermally conductive material exhibiting high thermal conductivity. This is thought to be because, while rod-shaped compounds can only conduct heat linearly (one-dimensionally), disc-shaped compounds can conduct heat planarly (two-dimensionally) in the direction of the normal, thus increasing the number of heat conduction paths and improving thermal conductivity.

[0076] The disc-shaped compound described above preferably has three or more epoxy groups. Cured products of curable compositions containing a disc-shaped compound having three or more epoxy groups tend to have a high glass transition temperature and high heat resistance. The number of epoxy groups in the disc-shaped compound is preferably 8 or less, and more preferably 6 or less. The lower limit is preferably 1 or more, and more preferably 3 or more.

[0077] Examples of disc-shaped compounds include compounds in which at least one (preferably three or more) of the terminal groups are epoxy groups, such as those described in C. Destrade et al., Mol. Crysr. Liq. Cryst., vol. 71, page 111 (1981); The Chemical Society of Japan, ed., Quarterly Review of Chemistry, No. 22, Chemistry of Liquid Crystals, Chapter 5, Chapter 10 Section 2 (1994); B. Kohne et al., Angew. Chem. Soc. Chem. Comm., page 1794 (1985); J. Zhang et al., J. Am. Chem. Soc., vol. 116, page 2655 (1994) and Japanese Patent No. 4592225. Examples of disc-shaped compounds include the triphenylene structure described in Angew. Chem. Int. Ed. 2012, 51, 7990-7993 and Japanese Patent Publication No. Hei 7-306317, and compounds in which at least one (preferably three or more) terminal groups of the trisubstituted benzene structure described in Japanese Patent Publication No. 2007-002220 and Japanese Patent Publication No. 2010-244038 are epoxy groups.

[0078] -Other epoxy compounds- In addition to the epoxy compounds mentioned above, epoxy compounds can also be those represented by formulas (Z), (Z1), or (Z2) described in the explanation of phenolic compounds, in which the phenolic hydroxyl group is replaced with an epoxy-containing group. An epoxy-containing group is either a group that is an epoxy group itself, or a monovalent group that contains an epoxy group as part of it. A monovalent group containing the above epoxy group in part is a group having one or more epoxy groups (preferably 1 to 8) within the entire group. The monovalent group containing the above epoxy group in part is "-(divalent hydrocarbon group) M1 -(-O-2 valent hydrocarbon group-) M2A group represented as "-epoxy group" is preferred. In the above group, M1 represents 0 or 1. M2 represents an integer of 1 or more (preferably 1 to 10). Examples of divalent hydrocarbon groups in the above group include alkylene groups (preferably with 1 to 6 carbon atoms), alkenylene groups (-CH=CH- etc., preferably with 2 to 6 carbon atoms), alkylene groups (-C≡C- etc., preferably with 2 to 6 carbon atoms), arylene groups (phenylene groups etc., preferably with 6 to 15 carbon atoms), and groups combining these. The above divalent hydrocarbon group may or may not have substituents, and the above divalent hydrocarbon group may further have an epoxy-containing group as a substituent. Multiple such divalent hydrocarbon groups may exist, and they may be the same or different.

[0079] Other epoxy compounds include, for example, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, bisphenol AD ​​type epoxy compounds, etc., which are glycidyl ethers of bisphenol A, F, S, AD, etc.; hydrogenated bisphenol A type epoxy compounds, hydrogenated bisphenol AD ​​type epoxy compounds, etc.; phenol novolac type glycidyl ethers (phenol novolac type epoxy compounds), cresol novolac type glycidyl ethers (cresol novolac type epoxy compounds), bisphenol A novolac type glycidyl ethers, etc.; dicyclopentadiene type glycidyl ethers (dicyclopentadiene type epoxy compounds); dihydroxypentadiene type glycidyl ethers (dihydroxypentadiene type epoxy compounds); polyhydroxybenzene type glycidyl ethers (polyhydroxybenzene type epoxy compounds), such as glycidyl ethers of dihydroxybenzene like resorcinol; benzene polycarboxylic acid type glycidyl esters (benzene polycarboxylic acid type epoxy compounds); trisphenolmethane type epoxy compounds; phenoxy resins, etc.; and acrylic resins having epoxy groups in their side chains. Compounds in which one or more glycidyl ether groups and / or glycidyl ester groups in each of the above-mentioned compounds are replaced with diglycidylamino groups or diglycidylaminoalkylene groups (such as diglycidylaminomethylene groups) may be used as epoxy compounds. Each of the above-mentioned compounds may have substituents. For example, the aromatic ring group, cycloalkane ring group and / or alkylene group contained in each of the above-mentioned compounds may have substituents other than glycidyl ether group, glycidyl ester group, diglycidylamino group and / or diglycidylaminoalkylene group.

[0080] The epoxy compound preferably contains one or more selected from the group consisting of polyhydroxybenzene type glycidyl ethers, bisphenol F type glycidyl ethers, epoxy compounds represented by formula (DN), rod-shaped compounds (preferably rod-shaped compounds having a biphenyl skeleton), disc-shaped compounds (preferably disc-shaped compounds with a biphenylene ring as the central ring, disc-shaped compounds with a triazine ring as the central ring, or disc-shaped compounds with a benzene ring as the central ring), phenol novolac type glycidyl ethers, and phenoxy resins.

[0081] The epoxy compound content is preferably 3 to 90% by mass, more preferably 5 to 50% by mass, and even more preferably 7 to 40% by mass, based on the total solid content of the curable composition.

[0082] (Maleimide compounds) Maleimide compounds are compounds having one or more maleimide groups. The number of maleimide groups in the maleimide compound is preferably 1 to 100, more preferably 2 to 10, and even more preferably 2. The maleimide compound may be either a high molecular weight compound or a low molecular weight compound. For example, the molecular weight of the maleimide compound is preferably 100 to 3,000, more preferably 200 to 2,000, and even more preferably 300 to 1,000.

[0083] The maleimide group in the maleimide compound is preferably the group represented by formula (M).

[0084] [ka]

[0085] In formula (M), * indicates a bonding position. X and Y each independently represent a hydrogen atom or a substituent. X and Y are preferably hydrogen atoms.

[0086] The maleimide compound is also preferably a compound having one or more (preferably 1 to 10) aromatic ring groups (such as benzene ring groups). Furthermore, the maleimide compound is also preferably a compound having a mesogenic group. The maleimide compound is preferably a compound represented by formula (1).

[0087] [ka]

[0088] In formula (1), m represents 0 or 1. m is preferably 1. n represents either 0 or 1. n is preferably 1.

[0089] In formula (1), R 1 and R 2 Each of these independently represents a hydrogen atom or a substituent. The substituent is preferably an alkyl group. The alkyl group may be linear or branched, and preferably has 1 to 10 carbon atoms. R when it is a substituent 1 and / or R 2 It is also preferable that it be located, for example, on a benzene ring group, adjacent to the maleimide group. R 1 and R 2 If both are substituents, R 1 and R 2 It is also preferable that each substituent is different, for example, R 1 R is a methyl group 2 It is also preferable that the group is an ethyl group.

[0090] In formula (1), L 1 This represents a divalent linking group. Examples of the above-mentioned divalent linking groups include ether groups (-O-), carbonyl groups (-CO-), ester groups (-COO-), thioether groups (-S-), -SO2-, -NR- (where R is a hydrogen atom or alkyl group), divalent aliphatic hydrocarbon groups (e.g., alkylene groups, cycloalkylene groups, alkenylene groups (-CH=CH- etc.), alkylylene groups (-C≡C- etc.)), divalent aromatic ring groups (arylene groups and heteroarylene groups), and groups that combine these. In formula (1), L 1 The number of carbon atoms is preferably 1 or more, more preferably 1 to 100, and even more preferably 3 to 15.

[0091] L 1 A mesogenic group is preferred, specifically, "* p -(L 2 -Ar) k -* q A base represented by " is preferred. * q * represents the bond position on the side that directly bonds with the maleimide group. p This indicates the opposite bonding position. k represents an integer greater than or equal to 1, preferably an integer between 1 and 10, and more preferably 1. L 2 This is a single bond, -C(R 3 )(R 4 )-, -O- or -CO- represents -C(R 3 )(R 4 )- is preferable. R 3 and R 4 Each of these independently represents a hydrogen atom or a substituent, and alkyl groups (which may be linear or branched, and have, for example, 1 to 10 carbon atoms) are preferred. Ar represents an arylene group. The number of ring member atoms of the arylene group is preferably 6 to 15, more preferably 6. If the arylene group has substituents, the number is preferably 1 to 4, more preferably 1 or 2. Preferred substituents that the arylene group may have are alkyl groups (which may be linear or branched, and have, for example, 1 to 10 carbon atoms). Possible structures of Ar include those explicitly shown in formula (1), such as R 1 and R2 Another possible structure is one in which a benzene ring group can bond with it. L 2 And if there are multiple Ars, then there are multiple Ls. 2 Each Ar element, and each other, may be identical or different.

[0092] In equation (1) when n is 1, R 1 and R 2 On the benzene ring group bonded to the maleimide group, "-(L 1 ) m The two groups represented by the "-maleimide group" may be positioned in the ortho, meta, or para positions relative to each other. Preferably, the two groups are positioned in the meta or para positions.

[0093] The compound represented by formula (1) is such that m represents 1, n represents 1, and L 1 The number of carbon atoms in the divalent linking group represented by is preferably 3 to 15.

[0094] Maleimide compounds may be used individually or in combination of two or more. The maleimide compound content is preferably 0.1 to 40% by mass, more preferably 1 to 15% by mass, and even more preferably 3.5 to 8% by mass, based on the total solid content of the curable composition. Furthermore, in order to obtain a more superior thermal conductivity and / or insulating properties for the resulting thermal conductive material, it is also preferable that the maleimide compound content be 6% by mass or more (for example, 6-12% by mass) relative to the total solid content of the curable composition. When the curable composition contains an epoxy compound, the maleimide compound content is, for example, 1 to 200% by mass, preferably 5 to 100% by mass, more preferably 10 to 70% by mass, and even more preferably 20 to 60% by mass, relative to the total content of the epoxy compound and the phenol compound. The maleimide compound content is, for example, 1 to 500% by mass relative to the phenol compound content, preferably 20 to 300% by mass, more preferably 50 to 200% by mass, and even more preferably 70 to 130% by mass.

[0095] (The relationship between phenolic compounds and epoxy compounds) When the curable composition contains an epoxy compound and a phenol compound, it is preferable that at least one of the following requirements is met: the phenol compound has a triazine skeleton (requirement A) and the epoxy compound has a triazine skeleton (requirement B). The curable composition may satisfy only requirement A, only requirement B, or both requirement A and requirement B.

[0096] For phenol compounds and epoxy compounds to "have a triazine skeleton" means that the compound contains one or more (e.g., 1 to 5) triazine ring groups. Examples of phenol compounds having a triazine skeleton include the compound represented by formula (Z), the compound represented by formula (Z1), and the compound represented by formula (Z2) mentioned above. Examples of epoxy compounds having a triazine skeleton include compounds represented by formula (Z) in which the phenolic hydroxyl group is replaced with an epoxy-containing group, compounds represented by formula (Z1) in which the phenolic hydroxyl group is replaced with an epoxy-containing group, and compounds represented by formula (Z2) in which the phenolic hydroxyl group is replaced with an epoxy-containing group.

[0097] When the phenol compound has a triazine skeleton (satisfying requirement A), the content of the phenol compound having a triazine skeleton is preferably more than 0% by mass and 100% by mass or less, more preferably 30 to 100% by mass, even more preferably 60 to 100% by mass, and particularly preferably 90 to 100% by mass, based on the total mass of the phenol compound. Furthermore, when the curable composition contains an epoxy compound and the epoxy compound has a triazine skeleton (satisfying requirement B), it is also preferable that the content of the phenol compound having a triazine skeleton be outside the above preferred range. When the epoxy compound has a triazine skeleton (satisfying requirement B), the content of the epoxy compound having a triazine skeleton is preferably more than 0% by mass and 100% by mass or less, more preferably 30 to 100% by mass, even more preferably 60 to 100% by mass, and particularly preferably 90 to 100% by mass, relative to the total mass of the epoxy compound. When the phenol compound has a triazine skeleton (satisfying requirement A), the content of the epoxy compound having a triazine skeleton may be outside the above preferred range.

[0098] When the curable composition contains an epoxy compound, it is also preferable that at least a portion of the phenol compound and the epoxy compound are compounds other than those having a triazine skeleton. The phenol compound may be a compound other than one having a triazine skeleton, and the epoxy compound may be a compound other than one having a triazine skeleton, either in whole or in part. When the curable composition contains an epoxy compound, in order to adjust the crosslinking density and further improve the effects of the present invention, the total content of the phenol compound having a triazine skeleton and the epoxy compound having a triazine skeleton is preferably more than 0% by mass and less than 100% by mass, more preferably 1 to 90% by mass, and even more preferably 5 to 80% by mass, relative to the total content of the phenol compound and the total epoxy compound.

[0099] In the curable composition, the total content of epoxy compounds and phenolic compounds is preferably 3 to 90% by mass, more preferably 5 to 50% by mass, and even more preferably 7 to 40% by mass, based on the total solid content of the curable composition.

[0100] The ratio of the total number of epoxy groups in the epoxy compound to the total number of hydroxyl groups (preferably phenolic hydroxyl groups) in the phenol compound (number of epoxy groups / number of hydroxyl groups) is often between 0.03 and 33, preferably between 0.4 and 2.5, more preferably between 0.6 and 1.5, and even more preferably between 0.8 and 1.3. In other words, the ratio of the content of phenol compounds to epoxy compounds in the curable composition is preferably such that the ratio of "number of epoxy groups / number of phenolic hydroxyl groups" falls within the above range.

[0101] The equivalent ratio (number of epoxy groups / number of active hydrogens) of epoxy groups to active hydrogens in epoxy compounds is often between 0.03 and 33, preferably between 0.4 and 2.5, more preferably between 0.6 and 1.5, and even more preferably between 0.8 and 1.3. The above-mentioned active hydrogen may be active hydrogen derived from a phenolic hydroxyl group, or it may be active hydrogen from other active hydrogen-containing compounds.

[0102] The ratio of the total number of epoxy groups in the epoxy compound to the total number of hydroxyl groups (preferably phenolic hydroxyl groups) in the phenol compound (number of epoxy groups / number of hydroxyl groups) is preferably 1.1 to 3.0, more preferably 1.2 to 2.0, and even more preferably 1.3 to 1.8. Furthermore, in particular, when the curable composition contains the above maleimide compound, it is preferable that the above ratio falls within the above range. If the above ratio is greater than or equal to a predetermined value, flexibility is introduced to the semi-cured film formed from the curable composition, improving storage stability, and the handling properties of the semi-cured film remain good even after a certain period of time has elapsed since its formation. If the above ratio is less than or equal to a predetermined value, the heat resistance of the heat-conducting material formed from the curable composition is further improved. These improvement effects are particularly pronounced when the curable composition contains a maleimide compound.

[0103] [Inorganic particles] The curable composition of the present invention contains inorganic particles selected from the group consisting of inorganic nitride particles and inorganic oxide particles.

[0104] Examples of inorganic nitride particles include boron nitride (BN), carbon nitride (C3N4), silicon nitride (Si3N4), gallium nitride (GaN), indium nitride (InN), aluminum nitride (AlN), chromium nitride (Cr2N), copper nitride (Cu3N), iron nitride (Fe4N), iron nitride (Fe3N), lanthanum nitride (LaN), lithium nitride (Li3N), magnesium nitride (Mg3N2), molybdenum nitride (Mo2N), niobium nitride (NbN), tantalum nitride (TaN), titanium nitride (TiN), tungsten nitride (W2N), tungsten nitride (WN2), yttrium nitride (YN), and zirconium nitride (ZrN). Examples of inorganic nitride particles include aluminum nitride (AlN) and boron nitride (BN), with boron nitride being preferred.

[0105] Examples of inorganic oxide particles include zirconium oxide (ZrO2), titanium oxide (TiO2), silicon oxide (SiO2), aluminum oxide (Al2O3), iron oxide (Fe2O3, FeO, Fe3O4), copper oxide (CuO, Cu2O), zinc oxide (ZnO), yttrium oxide (Y2O3), niobium oxide (Nb2O5), molybdenum oxide (MoO3), indium oxide (In2O3), Examples include In2O, tin oxide (SnO2), tantalum oxide (Ta2O5), tungsten oxide (WO3, W2O5), lead oxide (PbO, PbO2), bismuth oxide (Bi2O3), cerium oxide (CeO2, Ce2O3), antimony oxide (Sb2O3, Sb2O5), germanium oxide (GeO2, GeO), lanthanum oxide (La2O3), and ruthenium oxide (RuO2). Inorganic oxide particles may also be oxides produced when a metal prepared as a non-oxide is oxidized in the environment. Examples of inorganic oxide particles include silicon dioxide (silica, SiO2) and aluminum oxide (alumina, Al2O3), with alumina being preferred.

[0106] Particle size D of the inorganic particles 50 is often 10 μm or more, preferably 20 μm or more, and more preferably 30 μm or more. The upper limit is preferably 500 μm or less, more preferably 300 μm or less, still more preferably 200 μm or less, and particularly preferably 100 μm or less. Note that D 50 means the median diameter, and can be measured using, for example, a Mastersizer 2000 (manufactured by Malvern Panalytical). When using commercially available inorganic particles, the median diameter described in the catalog value can be adopted. Further, the median diameter can be obtained from the frequency distribution by measuring the particle sizes of any 100 selected using an electron microscope (for example, a scanning electron microscope and a transmission electron microscope, etc.). Note that when the inorganic particles are not spherical, the median diameter is determined with the longest diameter of the inorganic particles as the particle size.

[0107] Examples of the shape of the inorganic particles include rice grain shape, spherical shape, cubic shape, spindle shape, flake shape, aggregated shape (aggregate), and irregular shape, and an aggregate is preferred.

[0108] The inorganic particles are preferably surface-treated. The surface treatment means a treatment different from the surface modification with compound X or the like or compound Y or the like. By performing such a treatment, a functional group is introduced onto the surface of the inorganic particles, and the inorganic particles are considered to easily interact with the curable compound and / or compound X and compound Y or the like, and to be excellent in thermal conductivity and peel strength. Examples of the surface treatment include, for example, plasma treatment (for example, vacuum plasma treatment, atmospheric pressure plasma treatment, and aqua plasma treatment, etc.), ultraviolet irradiation treatment, corona treatment, electron beam irradiation treatment, ozone treatment, firing treatment, flame treatment, and oxidant treatment. The above oxidant treatment may be carried out under either acidic conditions or basic conditions (for example, pH 12 to 14, etc.). As the surface treatment, an oxidant treatment carried out under basic conditions is preferred.

[0109] The inorganic particles may be used alone or in combination of two or more. The content of the inorganic particles is preferably 20% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, and particularly preferably 80% by mass or more, based on the total solid content of the curable composition. The upper limit is preferably less than 100% by mass, more preferably 95% by mass or less, and still more preferably 85% by mass or less, based on the total solid content of the curable composition.

[0110] [Requirement 1] Requirement 1 means that the inorganic particles are surface-modified with at least one selected from the group consisting of compound X, its hydrolyzate, and its hydrolysis condensate. In the above Requirement 1, when the inorganic particles are surface-modified with compound X or the like, it means that at least a part of the surface of the inorganic particles is covered with compound X or the like. It is preferable that at least a part of the surface of the inorganic particles is covered with compound X or the like via various bonds, and it is more preferable that at least a part of the surface of the inorganic particles is covered with compound X or the like via a "-Si-O-" bond. It is considered that the surface modification of the inorganic particles with compound X or the like can enhance the dispersibility of the inorganic particles in the curable composition. Moreover, the curable composition satisfying Requirement 1 only needs to contain inorganic particles surface-modified with compound X or the like, and may also contain inorganic particles not surface-modified with compound X or the like (for example, inorganic particles surface-modified with compound Y or the like and inorganic particles not surface-modified, etc.).

[0111] (Compound X) Compound X is a compound having one or more acid anhydride groups and two or more alkoxysilyl groups.

[0112] The number of acid anhydride groups that compound X has is 1 or more, preferably 2 or more, and more preferably 3 or more. The upper limit is preferably 5 or less, and more preferably 4 or less. The number of alkoxysilyl groups that compound X has is 2 or more, and preferably is 3 or more. The upper limit is preferably 6 or less, and more preferably 5 or less.

[0113] -Acid anhydride group- The acid anhydride group is a group represented as -CO-O-CO-. The acid anhydride group may be either a monovalent or divalent group. Compound X preferably has a group represented by formula (x-1) as an acid anhydride group, more preferably has a group represented by any of formulas (x-1-1) to (x-1-3), and even more preferably has a group represented by formula (x-1-1) or formula (x-1-2).

[0114] [ka]

[0115] In formula (x-1), * S and * T This represents the bond position with the carbon atom. however,* S The carbon atoms bonded together and * T The carbon atoms that are bonded together are directly bonded to each other.

[0116] The base represented by equation (x-1), and * S The carbon atoms bonded together, and * T The carbon atoms bonded to it form a five-membered ring together. Also,* S The carbon atoms bonded together, and * T There are no restrictions on the type of bond with the carbon atom to which it is bonded; for example, it can be a single bond or a double bond. Also, the group represented by formula (x-1) and * S The carbon atoms bonded together, and * T The five-membered ring formed jointly by the bonded carbon atoms is fused to an aromatic ring (e.g., a benzene ring), * S The carbon atoms bonded together are * T The carbon atom bonded by the ring may be an adjacent ring member atom within the same aromatic ring. The above aromatic ring may be monocyclic or polycyclic, and may or may not have heteroatoms. The number of ring member atoms is preferably 5 to 15.

[0117] [ka]

[0118] In formula (x-1-1), R x11 ~R x14 Each of these independently represents a hydrogen atom, a substituent, or a bond position. However, R x11 ~R x14 Of these, 1 or 2 represents the bonding position. Examples of the substituents include groups selected from the substituent group Y described above. Furthermore, the total number of atoms other than hydrogen atoms in the substituents is, for example, 1 to 20.

[0119] In formula (x-1-2), R x21 and R x22 Each of these independently represents a hydrogen atom, a substituent, or a bond position. However, R x21 and R x22 At least one of these represents a bond location. R x21 and R x22 Examples of substituents represented by include groups selected from the substituent group Y described above. Furthermore, the total number of atoms other than hydrogen atoms in the substituent is, for example, 1 to 20.

[0120] In formula (x-1-3), * represents a bond position. W represents a ring which may have substituents. m represents 1 or 2. n represents an integer greater than or equal to 0. The ring represented by W may be either an alicyclic ring or an aromatic ring. The number of carbon atoms in the above alicyclic ring is preferably 3 to 30, and more preferably 3 to 15. The above alicyclic ring may be either a monocyclic or polycyclic ring. Further, the above polycyclic ring may be either a spiro ring or a bridged alicyclic ring. Specifically, as the bridged alicyclic ring, in two or more -CH2- groups that constitute the ring of the alicyclic ring, groups obtained by removing one hydrogen atom from each -CH2- may be bonded to each other via a divalent linking group. Examples of the above divalent linking group include an alkylene group, -O-, -CO-, -COO-, -S-, -SO2-, and -NR- (R is a hydrogen atom or an alkyl group). Examples of the above bridged alicyclic group include polycyclic cycloalkane rings such as a norbornane ring and an adamantane ring. Examples of the above alicyclic ring include monocyclic cycloalkane rings such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cyclooctane ring, a cyclononane ring, a cyclodecane ring, and a cyclododecane ring. The above aromatic ring represented by W may be either monocyclic or polycyclic, may or may not have a hetero atom, and the number of ring member atoms is, for example, 5 to 15. The above aromatic ring is preferably a benzene ring. n is preferably an integer of 0 to 2, more preferably 0 or 1. In formula (x-1-3), there are (n + 1) five-membered rings having a group represented by -CO-O-CO-, and the (n + 1) five-membered rings are fused to an aromatic ring represented by Ar. Examples of the substituent that the ring represented by W may have include a group selected from the substituent group Y, and an alkyl group is preferred. Further, examples of the above substituent also include a group represented by formula (x-1).

[0121] Compound X preferably has a repeating unit having an acid anhydride group as an acid anhydride group, more preferably has a repeating unit represented by any one of formula (x-2) to formula (x-4), and even more preferably has a repeating unit represented by formula (x-3) or a repeating unit represented by formula (x-4).

[0122]

Chemical formula

[0123] In formula (x-3), R x1 L represents a hydrogen atom or a methyl group. x1 This represents a single bond or a divalent linking group. In formula (x-4), R x2 L represents a hydrogen atom or a methyl group. x2 represents a single bond or a divalent linking group. Ar represents an aromatic ring which may have substituents.

[0124] In formula (x-3), R x1 L represents a hydrogen atom or a methyl group. x1 This represents a single bond or a divalent linking group. R x1 A hydrogen atom is preferred as the element. L x1 A single bond is preferred. L x1 Examples of divalent linking groups represented by include ether groups (-O-), carbonyl groups (-CO-), ester groups (-COO-), thioether groups (-S-), -SO2-, and -NR. T -(R T ) represents a hydrogen atom, alkyl group, or aryl group. ), -CONR T Examples include divalent aliphatic hydrocarbon groups (e.g., alkylene groups, cycloalkylene groups, alkenylene groups (-CH=CH- etc.) and alkylylene groups (-C≡C- etc.)), divalent aromatic ring groups (e.g., arylene groups and heteroarylene groups), and groups that combine these. L x1 Examples of divalent linking groups represented by -COO- and -NR T -, -CONR T -, alkylene groups, phenylene groups, or groups obtained by combining two or more of these are preferred. T represents a hydrogen atom, a methyl group, or an ethyl group. Examples of groups combining two or more of the above include the -COO-alkylene group- and the -COO-alkylene group-OCO-.

[0125] In formula (x-4), R x2L represents a hydrogen atom or a methyl group. x2 represents a single bond or a divalent linking group. Ar represents an aromatic ring which may have substituents. R x2 , L x2 And Ar are R x1 , L x1 This is synonymous with an aromatic ring which may have substituents represented by W, and the preferred embodiment is the same. The ring containing the acid anhydride group and the aromatic ring, which may have substituents represented by Ar, are condensed.

[0126] -alkoxysilyl group- Compound X preferably has a group represented by formula (z-1) as an alkoxysilyl group.

[0127] [ka]

[0128] In equation (z-1), * represents the bond position. z11 ~R z13 Each of these independently represents an alkoxy group, a hydroxyl group, or an alkyl group. However, R z11 ~R z13 At least one of these represents an alkoxy group. R z11 ~R z13 The alkyl group of the alkoxy group represented by R may be linear or branched, but linear is preferred. The alkyl group of the alkoxy group may also have substituents, but an unsubstituted alkyl group is preferred. The number of carbon atoms in the alkyl group of the alkoxy group is preferably 1 to 6, more preferably 1 to 3, and even more preferably 1 or 2. In other words, R z11 ~R z13 The alkoxy group represented by is preferably a methoxy group or an ethoxy group. The above R z11 ~R z13 The alkyl group represented by may be linear or branched, but linear is preferred. Also, R z11 ~Rz13 The alkyl group represented by may have substituents, but an unsubstituted alkyl group is preferred. z11 ~R z13 The number of carbon atoms in the alkyl group represented is preferably 1 to 6, more preferably 1 to 3, and even more preferably 1 or 2.

[0129] Preferred embodiments of the alkoxysilyl group include R z11 ~R z13 One embodiment is in which all of them are alkoxy groups, z11 ~R z13 It is preferable that all of them are methoxy groups or ethoxy groups.

[0130] Compound X may also preferably have a repeating unit represented by formula (z-2) as an alkoxysilyl group.

[0131] [ka]

[0132] In formula (z-2), R z21 L represents a hydrogen atom or a methyl group. z21 R represents a single bond or a divalent linking group. z11 ~R z13 Each of these independently represents an alkoxy group, a hydroxyl group, or an alkyl group. However, R z11 ~R z13 At least one of these represents an alkoxy group.

[0133] R z11 ~R z13 This is R in the above equation (z-1). z11 ~R z13 This is synonymous with the same thing, and the preferred embodiment is also the same. R z21 A hydrogen atom is preferred as the element. L z21 As such, single bonds or alkyl groups are preferred. L z21 Examples of divalent linking groups represented by include L x A divalent linking group represented by is an example.

[0134] -Other basics- Compound X may have other groups in addition to the groups described above. Other preferred groups include -S-, and more preferably -SC(=S)-S-.

[0135] Compound X is preferably the compound represented by formula (X-1).

[0136] [ka]

[0137] In formula (X-1), Y X This represents a group having the group represented by formula (x-1). X1 and L X2 Each of these independently represents a single bond or a divalent linking group. X is, n X +m X Represents a valence linking group. Z X This represents an alkoxysilyl group. X m represents an integer greater than or equal to 1. X This represents an integer greater than or equal to 2.

[0138] Y X This represents a group having the group represented by formula (x-1). Y X The group represented by only needs to have the group represented by formula (x-1), and the group represented by formula (x-1) itself, and Y X Any of the groups represented by the formula (x-1) may be a group that has a part of the group represented by the formula (x-1). The group represented by the formula (x-1) is as described above. Y x Preferably, the group is represented by any of the above formulas (x-1-1) to (x-1-3), more preferably a repeating unit represented by any of the above formulas (x-2) to (x-4), and even more preferably a polymer chain having a repeating unit represented by any of the above formulas (x-2) to (x-4). Examples of the polymer chains mentioned above include vinyl polymers, ester polymers, ether polymers, urethane polymers, amide polymers, epoxy polymers, and silicone polymers.

[0139] The polymer chain described above may have other repeating units in addition to the repeating units described above. Other repeating units include, for example, the repeating unit represented by formula (P-1) and the repeating unit represented by formula (P-2).

[0140] [ka]

[0141] In formula (P-1), R P1 This represents an aromatic ring group which may have substituents.

[0142] R P1 This represents an aromatic ring group which may have substituents. The above aromatic ring group may be monocyclic or polycyclic, and may be an aromatic hydrocarbon ring group or an aromatic heterocyclic group. Examples of heteroatoms in the above aromatic heterocyclic group include oxygen atoms, sulfur atoms, and nitrogen atoms. The number of ring member atoms in the above aromatic ring group is preferably 5 to 15. Examples of substituents that the above aromatic ring group may have include groups selected from the substituent group Y described above, with alkyl groups being preferred and methyl groups being more preferred. Furthermore, the total number of atoms other than hydrogen atoms in the above substituent is, for example, 1 to 20. The number of substituents that the above aromatic ring group may have is, for example, 0 to 5. R P1 A preferred component is a benzene ring group which may have substituents.

[0143] In formula (P-2), R P2 R represents a hydrogen atom or a methyl group. P3 represents a substituent. Examples of the substituents mentioned above include groups selected from the substituent group Y described above, with alkylene groups and alkoxy groups being preferred. The alkylene group may be linear, branched, or cyclic. The number of carbon atoms in the alkylene group is preferably 1 to 5. The alkyl group of the above alkoxy group may be linear, branched, or cyclic. The number of carbon atoms in the alkyl group of the above alkoxy group is preferably 1 to 5.

[0144] L X1 and L X2 Each of these independently represents a single bond or a divalent linking group. Examples of the above divalent linking group include L x A divalent linking group represented by is an example. L X1 and L X2 Examples of divalent linking groups represented by include ether groups (-O-), carbonyl groups (-CO-), ester groups (-COO-), thioether groups (-S-), -SO2-, -NR- (where R represents a hydrogen atom, an alkyl group, or an aryl group), divalent aliphatic hydrocarbon groups (e.g., alkylene groups, cycloalkylene groups, alkenylene groups (-CH=CH-, etc.), and alkynylene groups (-C≡C-, etc.)), divalent aromatic ring groups (e.g., arylene groups and heteroarylene groups), and groups formed by combining these. L X1 and L X2 The group is preferably a combination of two or more groups selected from -CO-, -O-, -S-, and alkylene groups. X1 and L X2 As for the group, -CO-(alkylene group)-, -CO-(alkylene group)-O-(alkylene group)-, or -CO-(alkylene group)-S-(alkylene group)- are preferred. Also, L X1 and L X2 The preferred elements are -COO-(alkylene group)-, -COO-(alkylene group)-O-(alkylene group)-, or -COO-(alkylene group)-S-(alkylene group)-. The alkylene group may be in the form of either a linear or branched chain. The number of carbon atoms in the alkylene group is preferably 1 to 10, and more preferably 1 to 5.

[0145] n X m represents an integer greater than or equal to 1. X This represents an integer greater than or equal to 2. n X The integer is preferably between 1 and 5, more preferably between 1 and 3, and even more preferably 2 or 3. m X The integer is preferably between 2 and 5, more preferably between 2 and 4, and even more preferably 2 or 3.

[0146] A X is, n X +m X It represents a valence linking group. n X +m X The integer is preferably between 3 and 10, more preferably between 3 and 8, and even more preferably between 3 and 6. n X +m X Examples of valency linking groups include trivalent linking groups such as nitrogen atoms (>N-) and trimethylolpropane residues, groups represented by >NLN<, tetravalent or pentavalent linking groups such as pentaerythritol residues, hexavalent linking groups such as dipentaerythritol residues, and groups combining these. In the above >NLN< group, L represents a divalent linking group, for example, L x A divalent linking group represented by is an example.

[0147] A X Examples include groups represented by any of formulas (E) to (J) or combinations thereof, with groups represented by formula (E), formula (F), or formula (H) being preferred.

[0148] [ka]

[0149] In equations (E) to (J), * indicates the bonding position. In formula (E), R represents a hydrogen atom or a substituent. In equation (J), t represents an integer greater than or equal to 2.

[0150] Z X This represents an alkoxysilyl group. The above-mentioned alkoxysilyl group is synonymous with the alkoxysilyl group described above, and the preferred embodiment is also the same.

[0151] (Hydrolyzed product of compound X) The alkoxysilyl group in compound X is readily hydrolyzed to a silanol group. The hydrolysate of compound X may be a product in which all hydrolyzable groups, such as the alkoxysilyl group, have been hydrolyzed (complete hydrolysate), or a product in which only some of the hydrolyzable groups, such as the alkoxysilyl group, have been hydrolyzed (partial hydrolysate). In other words, the hydrolysate may be a complete hydrolysate, a partial hydrolysate, or a mixture thereof. Silanol groups readily condense with hydroxyl groups and other groups present on the surface of inorganic particles to form a "-Si-O-inorganic particle surface" bond.

[0152] (Hydrolysis condensate of compound X) The hydrolyzed product of compound X can undergo dehydration condensation between two molecules, forming a -Si-O-Si bond through dehydration condensation of the silanol groups. The alkoxysilyl group of compound X remains as a silanol group even in the hydrolyzed product of compound X, and like the hydrolyzed product of compound X, it readily condenses with hydroxyl groups on the surface of inorganic particles to form a "-Si-O-inorganic particle surface" bond.

[0153] Examples of compound X include the following compounds. Note that X in the formula is the same as A above. X This is the base represented by m, where m represents an integer from 1 to 4.

[0154] [ka]

[0155] The molecular weight of compound X is preferably 200 to 5000, and more preferably 300 to 3000. Furthermore, the weight-average molecular weight of compound X is preferably 5000 to 100000, and more preferably 10000 to 50000.

[0156] Compound X may be used alone or in combination of two or more compounds.

[0157] [Requirement 2] Requirement 2 is that the curable composition comprises at least one selected from the group consisting of compound X, its hydrolysates, and its hydrolyzed condensates. The above-mentioned compound X, its hydrolysate, and its hydrolyzed condensate are as described above in Requirement 1. Compound X may be used alone or in combination of two or more compounds. The content of compound X is preferably 0.01 to 10% by mass, more preferably 0.02 to 5% by mass, and even more preferably 0.05 to 1% by mass, relative to the total solid content of the curable composition.

[0158] [Requirement 3] Requirement 3 is that the inorganic particles are surface-modified with at least one selected from the group consisting of compound Y, its hydrolysates, and its hydrolyzed condensates. Furthermore, a curable composition that satisfies requirement 3 only needs to contain inorganic particles whose surface has been modified with compound Y, etc., and may also contain inorganic particles whose surface has not been modified with compound Y, etc. (for example, inorganic particles whose surface has been modified with compound X, etc., and inorganic particles whose surface has not been modified).

[0159] (Compound Y) Compound Y is a compound having one or more specific aromatic heterocycles and one or more alkoxysilyl groups.

[0160] The number of specific aromatic heterocycles in compound Y is 1 or more, preferably 2 or more, and more preferably 3 or more. The upper limit is preferably 5 or less, and more preferably 4 or less. The number of alkoxysilyl groups in compound Y is 1 or more, preferably 2 or more, and more preferably 3 or more. The upper limit is preferably 6 or less, and more preferably 5 or less.

[0161] -Specific Aromatic Heterocyclic Rings- A specific aromatic heterocycle is one or more aromatic heterocycles selected from the group consisting of pyrrole rings, imidazole rings, pyrazole rings, pyridine rings, pyridazine rings, pyrazine rings, pyrimidine rings, triazole rings, tetrazole rings, isoindole rings, indole rings, benzimidazole rings, indazole rings, benzotriazole rings, imidazopyridine rings, purine rings and their derivatives, pyrazolopyrimidine rings, triazolopyrimidine rings, benzothiazole rings, furan rings, and thiophene rings. Compound Y preferably has one or more aromatic heterocycles selected from the group consisting of a benzotriazole ring, a mercaptobenzothiazole ring, a pyrrole ring, an imidazole ring, a pyrazole ring, a tetrazole ring, an indole ring, a benzimidazole ring, an indazole ring, a purine ring and its derivatives, a pyrazolopyrimidine ring, and a triazolopyrimidine ring, and more preferably has a benzotriazole ring.

[0162] Examples of purine derivatives include rings derived from compound P. Examples of compound P include adenine, guanine, hypoxanthine, xanthine, theobromine, caffeine, uric acid, isoguanine, adenosine, emprophylline, xanthosine, 7-methylxanthosine, 7-methylxanthine, theophylline, eritadenine, paraxanthine, 3-methyladenine, 3-methylxanthine, 1,7-dimethylxanthine, and 1-methylxanthine.

[0163] The above-mentioned specific aromatic heterocycle may further have substituents. Examples of the substituents mentioned above include groups selected from substituent group Y.

[0164] Compound Y preferably has a specific aromatic heterocycle, and more preferably has a group represented by formula (y-1).

[0165] [ka]

[0166] In equation (y-1), * represents a bond position. H represents a specific aromatic heterocycle. The specific aromatic heterocycles mentioned above are as described above.

[0167] Compound Y may also have a repeating unit having a specific aromatic heterocycle, and more preferably a repeating unit represented by formula (y-2).

[0168] [ka]

[0169] In formula (y-2), R y L represents a hydrogen atom or a methyl group. y represents a single bond or a divalent linking group. H represents a specific aromatic heterocycle. Examples of divalent linking groups include L x A divalent linking group represented by is an example. Examples of divalent linking groups include -COO-, -S-, and -NR. T -, -CONR T -, alkylene groups, phenylene groups, or combinations thereof are preferred. T represents a hydrogen atom, a methyl group, or an ethyl group. Examples of the above-mentioned combined groups include -COO-alkylene group-, -COO-alkylene group-OCO-, -COO-alkylene group-OCO-alkylene group-, and -COO-alkylene group-OCO-alkylene group-S-. The specific aromatic heterocycle represented by H above is as described above.

[0170] -alkoxysilyl group- Compound Y preferably has a group represented by formula (z-1) as an alkoxysilyl group. It is also preferable that it has a repeating unit represented by formula (z-2). The base represented by formula (z-1) and the repeating unit represented by formula (z-2) are as described above.

[0171] -Other basics- Compound Y may have other groups besides the groups mentioned above. Other preferred groups include -S-, and more preferably -SC(=S)-S-.

[0172] Compound Y is preferably the compound represented by formula (Y-1).

[0173] [ka]

[0174] In equation (Y-1), Y Y This represents a polymer chain having repeating units represented by formula (y-2). Y1 and L Y2 Each of these independently represents a single bond or a divalent linking group. Y is, n Y +m Y Represents a valence linking group. Z Y This represents an alkoxysilyl group. Y m represents an integer greater than or equal to 1. Y This represents an integer greater than or equal to 1.

[0175] Y Y This represents a polymer chain having repeating units represented by formula (y-2). The repeating unit represented by the above formula (y-2) is as described above. Examples of the polymer chains mentioned above include vinyl polymers, ester polymers, ether polymers, urethane polymers, amide polymers, epoxy polymers, and silicone polymers.

[0176] The polymer chain described above may have other repeating units in addition to the repeating units described above. Other repeating units include, for example, the repeating unit represented by equation (P-1) and the repeating unit represented by equation (P-2) described above.

[0177] L Y1 and L Y2 Each of these independently represents a single bond or a divalent linking group. Examples of the above divalent linking group include L X1 and L X2 A divalent linking group represented by is an example.

[0178] n Y m represents an integer greater than or equal to 1. Y This represents an integer greater than or equal to 1. n Y The integer is preferably between 1 and 5, more preferably between 1 and 3, and even more preferably 2 or 3. m Y The integer is preferably between 1 and 5, more preferably between 2 and 4, and even more preferably 2 or 3.

[0179] A Y is, n Y +m Y It represents a valence linking group. n Y +m Y The integer is preferably between 3 and 10, more preferably between 3 and 8, and even more preferably between 3 and 6. n Y +m Y As for the valence linking group, the above-mentioned n X +m X A valence linking group is one example.

[0180] Z Y This represents an alkoxysilyl group. The alkoxysilyl group described above is as stated above.

[0181] Preferred embodiments of compound Y include, for example, Embodiment 1 and Embodiment 2. Embodiment 1: Compound Y is a compound having a repeating unit represented by formula (y-2), a group represented by formula (z-1), and -SC(=S)-S-. Embodiment 2: Compound Y is a compound represented by formula (Y-1).

[0182] (Hydrolyzed product of compound Y) The alkoxysilyl group in compound Y is readily hydrolyzed to a silanol group. The hydrolysate of compound Y may be a product in which all hydrolyzable groups, such as the alkoxysilyl group, have been hydrolyzed (complete hydrolysate), or a product in which only some of the hydrolyzable groups, such as the alkoxysilyl group, have been hydrolyzed (partial hydrolysate). In other words, the hydrolysate may be a complete hydrolysate, a partial hydrolysate, or a mixture thereof. Silanol groups readily condense with hydroxyl groups and other groups present on the surface of inorganic particles to form a "-Si-O-inorganic particle surface" bond.

[0183] (Hydrolysis condensate of compound Y) The hydrolysate of compound Y can undergo dehydration condensation between two molecules, forming a -Si-O-Si bond, and thus become a hydrolysis condensate. The alkoxysilyl group present in compound Y remains as a silanol group even in the hydrolysis condensate of compound Y, and, similar to the hydrolysate of compound Y, readily condenses with hydroxyl groups, etc., present on the surface of inorganic particles to form a "-Si-O-inorganic particle surface" bond.

[0184] The molecular weight of compound Y is preferably 200 to 5000, and more preferably 300 to 3000. Furthermore, the weight-average molecular weight of compound Y is preferably 5000 to 100000, and more preferably 10000 to 50000.

[0185] Compound Y may be used alone or in combination of two or more compounds.

[0186] [Requirement 4] Requirement 4 is that the curable composition comprises at least one selected from the group consisting of compound Y, its hydrolysates, and its hydrolyzed condensates. The above compound Y, its hydrolysate, and its hydrolyzed condensate are as described above in Requirement 3. Compound Y may be used alone or in combination of two or more compounds. The content of compound Y is preferably 0.01 to 10% by mass, more preferably 0.02 to 5% by mass, and even more preferably 0.05 to 1% by mass, relative to the total solid content of the curable composition.

[0187] [Curing accelerator] The curable composition may contain a curing accelerator. The curing accelerator preferably contains at least one compound selected from the group consisting of compounds represented by formula (P1) and compounds represented by formula (P2), and more preferably contains a compound represented by formula (P3). If optical isomers exist in the compound contained in the curing accelerator, either optical isomer may be used. Furthermore, one optical isomer may be used alone, or multiple optical isomers may be used in mixture form. When mainly using one optical isomer, its optical purity (ee) is preferably 90 or higher, and more preferably 95 or higher. Similarly, in formulas (P1) to (P3), if optical isomers exist, any of the optical isomers may be included.

[0188] [ka]

[0189] In formula (P1), L p This represents a single bond or a divalent linking group. Examples of the above-mentioned divalent linking groups include ether groups (-O-), carbonyl groups (-CO-), ester groups (-COO-), thioether groups (-S-), -SO2-, -NR- (where R represents a hydrogen atom or alkyl group), divalent aliphatic hydrocarbon groups (e.g., alkylene groups, cycloalkylene groups, alkenylene groups (-CH=CH-, etc.), alkylylene groups (-C≡C-, etc.)), divalent aromatic ring groups (e.g., arylene groups and heteroarylene groups, etc.), and groups formed by combining these. The above-mentioned divalent linking groups may further have substituents. Examples of the above substituents include those exemplified by substituent group Y. The above-mentioned arylene group may be monocyclic or polycyclic, and preferably has 6 to 25 carbon atoms. The above-mentioned arylene group is preferably a phenylene group, a naphthylene group, an anthracenylene group, or a binaphthylene group, with the binaphthylene group being more preferred. L p Preferably, the group is a divalent aliphatic hydrocarbon group or a divalent aromatic ring group, and more preferably an alkylene group or an arylene group.

[0190] R p11 ~R p14 Each of these independently represents a phenyl group which may have substituents. Examples of the substituents mentioned above include those exemplified in substituent group Y, with alkyl groups being preferred, and linear or branched alkyl groups having 1 to 3 carbon atoms being more preferred.

[0191] n p n represents 0 or 1. p Of these, 1 is preferable.

[0192] [ka]

[0193] In formula (P2), R p21 ~R p24 Each of these independently represents a phenyl group which may have substituents. Examples of the substituents mentioned above include those exemplified in substituent group Y, with alkyl groups being preferred, and linear or branched alkyl groups having 1 to 3 carbon atoms being more preferred.

[0194] X - This represents an anion. Examples of the above anions include hydroxide ions, fluoride ions, chloride ions, bromide ions, iodide ions, hexafluorophosphate ions, tetrafluoroborate ions, tetraphenylborate ions, dicyanamide ions, alkyl phosphate ions (e.g., diethyl phosphate ions), bisulfate ions, dihydrogen phosphate ions, hydrogen phosphate ions, sulfamate ions, perchlorate ions, benzotriazolide anions, and tetratolylborate anions (e.g., tetra-p-tolylborate anions). The tetratolyl borate anion is preferred as the above anion.

[0195] [ka]

[0196] In formula (P3), R p31 ~R p34 Each of these independently represents a phenyl group which may have substituents. Examples of the substituents mentioned above include substituents selected from the substituent group Y, with alkyl groups being preferred, and linear or branched alkyl groups having 1 to 3 carbon atoms being more preferred.

[0197] The molecular weight of the curing accelerator is often 200 or more, preferably 250 or more, more preferably 400 or more, even more preferably 430 or more, and particularly preferably 600 or more. The upper limit is preferably 10,000 or less, more preferably 1,000 or less, and even more preferably 800 or less. When the molecular weight of the curing accelerator is 250 or higher, the volatilization of the curing accelerator itself and / or its thermal decomposition products can be further suppressed when heat treatment is applied at high temperatures, resulting in superior solder heat resistance. Furthermore, when the molecular weight of the curing accelerator is 10,000 or less, it functions more easily as a curing accelerator.

[0198] The curing accelerator preferably contains a compound containing a phosphorus atom, and more preferably contains a phosphonium salt, from the viewpoint of achieving superior effects in the present invention. The curing accelerator may be a compound containing a phosphorus atom or the phosphonium salt itself. When a phosphonium salt is used as the curing accelerator, the storage stability of the semi-cured film formed from the curable composition is also improved. The content of a compound containing a phosphorus atom or a phosphonium salt is preferably 10 to 100% by mass, more preferably 50 to 100% by mass, and even more preferably 80 to 100% by mass, relative to the total mass of the curing accelerator.

[0199] The curing accelerator may be used individually or in combination of two or more types. The content of the curing accelerator is preferably 0.002% by mass or more, more preferably 0.02% by mass or more, and even more preferably 0.07% by mass or more, relative to the total solid content of the curable composition. The upper limit is preferably 5% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less, relative to the total solid content of the curable composition. The curing accelerator content is preferably 0.01% by mass or more, more preferably 0.10% by mass or more, and even more preferably 0.55% by mass or more, relative to the total epoxy compound. The upper limit is preferably 40% by mass or less, more preferably 12% by mass or less, even more preferably 10% by mass or less, and particularly preferably 5% by mass or less, relative to the total epoxy compound.

[0200] [Ion scavenger] The curable composition may contain an ion scavenger. The ion scavenger adsorbs ionic impurities in the curable composition or in the thermal conductive material formed using the curable composition. This allows the thermal conductive material to maintain better insulation properties even when it absorbs moisture. Examples of ion scavenging agents include inorganic ion scavenging agents and organic ion scavenging agents. Examples of organic ion scavengers include triazinethiol compounds, triazineamine compounds, benzimidazole compounds, benzotriazole compounds, aminotriazole compounds, and bisphenol-based reducing agents. Furthermore, all or part of the aforementioned inorganic particles may also function as ion scavengers.

[0201] Ion scavenging agents may be used individually or in combination of two or more types. When the curable composition contains an ion scavenger, the content of the ion scavenger (inorganic ion scavenger and / or organic ion scavenger) is preferably 0.01 to 10% by mass, more preferably 0.1 to 20% by mass, and even more preferably 0.2 to 10% by mass, relative to the total solid content of the curable composition.

[0202] [Other ingredients] The curable composition may contain other components in addition to the components listed above. Other components include, for example, inorganic particles surface-modified with at least one selected from the group consisting of compounds having one or more acid anhydride groups and one alkoxysilyl group, their hydrolysates, and their hydrolysate condensates; at least one compound selected from the group consisting of compounds having one or more acid anhydride groups and one alkoxysilyl group, their hydrolysates, and their hydrolysate condensates; inorganic particles surface-modified with at least one selected from the group consisting of compounds having one or more triazole rings and one or more alkoxysilyl groups, their hydrolysates, and their hydrolysate condensates; and at least one compound selected from the group consisting of compounds having one or more triazole rings and one or more alkoxysilyl groups, their hydrolysates, and their hydrolysate condensates. The other ingredients are described in detail below.

[0203] (acid anhydride) The curable composition may contain an acid anhydride. Acid anhydrides are compounds that have one or more acid anhydride groups (groups represented by -CO-O-CO-). Acid anhydrides are compounds different from the various components mentioned above.

[0204] The number of acid anhydride groups in an acid anhydride is 1 or more, preferably 2 or more, and more preferably 3 or more. The upper limit is preferably 1000 or less. The molecular weight of the acid anhydride (or weight-average molecular weight if there is a molecular weight distribution) is preferably 100 or more, more preferably 2,000 or more, and even more preferably 6,000 or more. The upper limit is preferably 100,000 or less, more preferably 30,000 or less, and even more preferably 17,000 or less. The acid anhydride may be a low-molecular-weight compound or a high-molecular-weight compound. Examples of low molecular weight acid anhydrides include maleic anhydride, phthalic anhydride, pyromellitic anhydride, and trimellitic anhydride. In a polymer compound, such as an acid anhydride, the acid anhydride group may be incorporated into the main chain or present in the side chain. For example, if the polymer compound has repeating units derived from maleic anhydride, the acid anhydride group contained in the repeating units shall be considered incorporated into the main chain.

[0205] Acid anhydrides may be used individually or in combination of two or more types. The acid anhydride content is preferably 0.01 to 40% by mass, more preferably 0.1 to 10% by mass, and even more preferably 0.6 to 5% by mass, relative to the total solid content of the curable composition. The acid anhydride content is preferably 0.1 to 100% by mass, more preferably 1 to 70% by mass, and even more preferably 5 to 60% by mass, relative to the total content of the epoxy compound and the phenol compound.

[0206] (solvent) The curable composition may contain a solvent. Organic solvents are preferred as solvents. Examples of organic solvents include cyclopentanone, cyclohexanone, ethyl acetate, methyl ethyl ketone, dichloromethane, and tetrahydrofuran. If the curable composition contains a solvent, the amount of solvent is preferably such that the solid content of the curable composition is 20 to 90% by mass, more preferably 30 to 85% by mass, and even more preferably 50 to 80% by mass. The solvent content is preferably 10 to 80% by mass, more preferably 15 to 70% by mass, and even more preferably 20 to 50% by mass, based on the total mass of the curable composition.

[0207] <Method for producing a curable composition> A known method can be used to produce the curable composition. For example, it can be produced by mixing the various components that may be included in the curable composition described above. When mixing, each main component may be mixed all at once or sequentially. For example, a method for producing a curable composition that satisfies requirement 1 above will be described in detail.

[0208] A method for producing a curable composition that satisfies requirement 1 includes, for example, a manufacturing method that includes a step of modifying the surface of inorganic particles with the above-mentioned compound X or the like (surface modification step). Furthermore, the above manufacturing method may also preferably further include a step of surface-treating inorganic particles to obtain modified inorganic particles (modification step). When the above modification step is included, it is preferable to carry out the modification step before the surface modification step. In other words, it is preferable to carry out the surface modification step on the surface of the modified inorganic particles. Therefore, a preferred method for producing a curable composition that satisfies requirement 1 is to mix inorganic particles surface-modified with compound X or the like with other various components that may be included in the curable composition described above. The following details each step.

[0209] [Modification process] The modification process is a process of obtaining modified inorganic particles by surface-treating inorganic particles. The modification process described above preferably involves contacting inorganic particles with an oxidizing agent in an aqueous solution to obtain modified inorganic particles.

[0210] Furthermore, the inorganic particles subjected to the above modification step are preferably boron nitride particles or aggregates thereof, and more preferably aggregates of boron nitride particles. Therefore, the resulting modified inorganic particles are preferably modified boron nitride particles or particles obtained by modifying aggregates of boron nitride particles, and more preferably particles obtained by modifying aggregates of boron nitride particles.

[0211] The above aqueous solution is preferably an alkaline aqueous solution. The pH of the above alkaline aqueous solution is often 8 or higher, preferably 12 or higher, more preferably greater than 12, even more preferably 13 or higher, and particularly preferably greater than 13. The upper limit is preferably 14 or lower. The pH of the above aqueous solution refers to the pH of the aqueous solution in a state in which inorganic particles and the above oxidizing agent are present. In other words, the above aqueous solution contains an alkaline compound, water, inorganic particles, and an oxidizing agent as needed.

[0212] In the above aqueous solution, the contact time between the inorganic particles and the oxidizing agent is preferably 0.1 to 24 hours, more preferably 0.5 to 10 hours, and even more preferably 1.5 to 6 hours. Furthermore, the temperature of the aqueous solution when the inorganic particles and the oxidizing agent are brought into contact is preferably 1 to 95°C, more preferably 25 to 80°C, and even more preferably 45 to 65°C.

[0213] One method for bringing inorganic particles and an oxidizing agent into contact in the above aqueous solution is, for example, contact in a mixed solution. Specifically, the inorganic particles, compound X or compound Y, and a mixed solution containing water and / or an organic solvent are brought into contact with each other.

[0214] Examples of organic solvents include methanol, ethanol, 2-propanol, acetonitrile, cyclopentanone, cyclohexanone, ethyl acetate, methyl ethyl ketone, dichloromethane, and tetrahydrofuran. Organic solvents may be used individually or in combination of two or more.

[0215] Methods for bringing inorganic particles and an oxidizing agent into contact include, for example, a method of contacting them while stirring using a mechanical stirrer such as a three-one motor or a magnetic stirrer, and a method of contacting them while circulating a solution containing an oxidizing agent with a cartridge filled with inorganic particles using a pump or the like.

[0216] It is preferable to bring the inorganic particles into contact with the oxidizing agent in the aqueous solution, and then remove the resulting modified inorganic particles from the aqueous solution. One method for extracting modified inorganic particles from the above aqueous solution is to filter the aqueous solution and separate the modified inorganic particles as a filter. It is also preferable to wash the extracted modified inorganic particles with water and / or an organic solvent. After washing, it is also preferable to dry the inorganic particles in an oven or the like.

[0217] In the above aqueous solution, the water content is preferably 20 to 99% by mass, more preferably 50 to 95% by mass, and even more preferably 65 to 90% by mass, based on the total mass of the aqueous solution.

[0218] (Oxidizing agent) Examples of oxidizing agents used in the modification process include persulfates such as sodium persulfate, potassium persulfate, and ammonium persulfate; nitrates such as cerium ammonium nitrate, sodium nitrate, and ammonium nitrate; peroxides such as hydrogen peroxide and tert-butyl hydroperoxide; transition metal compounds such as divalent copper compounds and manganese compounds; hypervalent iodine compounds such as potassium periodate and sodium periodate; quinone compounds such as benzoquinone, naphthoquinone, anthraquinone, and chloranil; and salts of halogen oxoacids such as sodium hypochlorite and sodium chlorite. The oxidizing agent preferably contains a persulfate, and more preferably is a persulfate. Furthermore, a catalyst may be used separately from the oxidizing agent to assist its action. Examples of such catalysts include divalent iron compounds (e.g., FeSO4) and trivalent iron compounds. The oxidizing agent and / or catalyst may also be in hydrate form.

[0219] The standard oxidation-reduction potential of the oxidizing agent is preferably 0.30V or higher, more preferably 1.50V or higher, and even more preferably 1.70V or higher. The upper limit is preferably 4.00V or lower, and more preferably 2.50V or lower. The above standard oxidation-reduction potential is a value based on a standard hydrogen electrode.

[0220] The oxidizing agent may be used alone or in combination of two or more types. In the above aqueous solution, the content of the oxidizing agent is preferably 0.05 to 20 parts by mass, more preferably 0.1 to 20 parts by mass, and even more preferably 1 to 20 parts by mass, per 100 parts by mass of water in the aqueous solution.

[0221] The catalyst may be used individually or in combination of two or more types. If the aqueous solution contains a catalyst, the amount of catalyst is preferably 0.005 to 2 parts by mass, more preferably 0.01 to 2 parts by mass, and even more preferably 0.1 to 2 parts by mass, per 100 parts by mass of water in the aqueous solution.

[0222] (Alkaline compounds) The above aqueous solution may also preferably contain an alkaline compound in addition to the above-mentioned components in order to adjust the pH of the aqueous solution. Examples of the alkali compounds mentioned above include inorganic bases such as alkali metal hydroxides (e.g., sodium hydroxide) and alkaline earth metal hydroxides, as well as organic bases. The amount of the alkaline compound in the aqueous solution may be such that it is used to appropriately adjust the pH of the aqueous solution to a desired value. For example, the amount may be 0.1 to 10 parts by mass per 100 parts by mass of water in the aqueous solution.

[0223] [Surface modification process] The surface modification step is a step of modifying the surface of inorganic particles with the above-mentioned compound X or compound Y. The surface modification step preferably involves bringing inorganic particles into contact with compound X or compound Y. Methods for bringing inorganic particles into contact with compound X or compound Y include those similar to those used in the modification step. The compound X or compound Y to be brought into contact with the inorganic particles is preferably a hydrolyzed or hydrolyzed condensed product of compound X or compound Y. In other words, it is preferable to subject compound X or compound Y to hydrolysis treatment before bringing it into contact with the inorganic particles.

[0224] (Hydrolysis treatment) Hydrolysis is a process of hydrolyzing compound X or compound Y. Through hydrolysis, the alkoxysilyl group of compound X or compound Y is hydrolyzed to generate a silanol group, which can then form a bond with the surface of inorganic particles.

[0225] The method of hydrolysis is not particularly limited, as long as the conditions are such that the alkoxy group in the alkoxysilyl group is hydrolyzed. Specifically, it is preferable to carry out the procedure using an acidic solution (for example, hydrochloric acid and aqueous acetic acid solutions). The above acidic solution may contain an organic solvent.

[0226] A known method can be used to mix the components that may be included in the curable composition. The mixing apparatus used for mixing is preferably a liquid-based disperser, and examples include agitators such as a rotary-orbit mixer and a high-speed rotary shear-type agitator, colloidal mills, roll mills, high-pressure jet dispersers, ultrasonic dispersers, bead mills, and homogenizers. The mixing apparatus may be used individually or in combination of two or more types. Degassing treatment may be performed before, after, and / or simultaneously with mixing.

[0227] <Method for curing a curable composition> The curable composition of the present invention is preferably a composition for forming a heat-conducting material. A heat-conducting material can be obtained by curing the curable composition of the present invention. A thermosetting reaction is preferred as the curing method for the curable composition. There are no particular restrictions on the heating temperature during the thermosetting reaction. For example, it can be appropriately selected within the range of 50 to 250°C. Furthermore, multiple heating treatments at different temperatures may be performed during the thermosetting reaction. The curing treatment is preferably performed on a curable composition in the form of a film or sheet. Specifically, for example, the curable composition may be coated and then a curing reaction may be carried out. When performing the curing treatment, it is preferable to apply the curable composition to the substrate to form a coating film and then cure it. In this case, the coating film formed on the substrate may be brought into contact with another substrate before the curing treatment is performed. The cured product (thermal conductive material) obtained after curing may be separated from one or both of the substrates, or it may not be separated. Furthermore, during the curing process, the curable composition may be applied to separate substrates to form coating films on each, and the curing process may be carried out with the resulting coating films in contact with each other. The cured material (thermal conductive material) obtained after curing may be separated from one or both of the substrates, or it may not be separated.

[0228] The curing process may be terminated when the curable composition reaches a semi-cured state. Alternatively, the curing process may be carried out further after the composition has reached a semi-cured state to complete curing. The curing treatment to bring the curable composition to a semi-cured state (hereinafter also referred to as the "semi-curing treatment") and the curing treatment to bring it to a complete cured state (hereinafter also referred to as the "main curing treatment") may be carried out in separate steps.

[0229] For example, in a semi-curing treatment, a curable composition may be applied to a substrate to form a coating film, and then the coating film on the substrate may be heated without pressure to obtain a semi-cured heat-conducting material (hereinafter also referred to as a "semi-cured film" or "semi-cured sheet"), or the coating film on the substrate may be heated while press working is performed to obtain a semi-cured film. When press working is performed, the press working may be performed before or after the heating, or during the process. Performing press working in a semi-curing treatment may make it easier to adjust the thickness of the resulting semi-cured film and / or reduce the amount of voids in the semi-cured film. In the semi-curing treatment, the treatment may be carried out with the coating films formed on separate substrates laminated together, or the treatment may be carried out without laminating the coating films together. The semi-curing treatment may also be carried out with the coating film formed from the curable composition in contact with a material other than the coating film.

[0230] The resulting semi-cured film may be used as is as a thermal conductive material, or it may be subjected to further curing treatment before being used as a fully cured thermal conductive material. In this curing process, the semi-cured film may be heated directly without pressure, or it may be heated after or while press-forming. In this case, the curing process may be performed with separate semi-cured films laminated together, or the curing process may be performed without laminating the semi-cured films together. Furthermore, this curing treatment may be carried out with the semi-cured film positioned so as to be in contact with the device or the like. It is also preferable that this curing treatment causes the device and the thermal conductive material of the present invention to bond together.

[0231] There are no restrictions on the type of press used for the press working that may be performed during the hardening process in the semi-hardening treatment and / or the full hardening treatment, etc. For example, a flat plate press or a roll press may be used. When using a roll press, for example, it is preferable to clamp a coated substrate, obtained by forming a coating film on a substrate, between a pair of opposing rolls, and apply pressure in the film thickness direction of the coated substrate while rotating the pair of rolls to pass the coated substrate through it. The coated substrate may have the substrate on only one side of the coating film, or it may have the substrate on both sides of the coating film. The coated substrate may pass through the roll press only once or multiple times. During the curing process in the semi-curing treatment and / or the full curing treatment, either the flat plate press treatment or the roll press treatment may be performed alone or both.

[0232] For information on the fabrication of thermally conductive materials, including curing reactions, please also refer to "High Thermal Conductivity Composite Materials" (CMC Publishing, authored by Yoshitaka Takezawa).

[0233] There are no particular restrictions on the shape of the heat conductive material, and it can be molded into various shapes depending on the application. A typical shape of molded heat conductive material is, for example, a sheet. In other words, the thermal conductive material obtained using the curable composition of the present invention is preferably a thermal conductive sheet. Furthermore, it is preferable that the thermal conductivity of the thermal conductive material obtained using the curable composition of the present invention is isotropic rather than anisotropic.

[0234] The thermal conductive material is preferably an insulating (electrically insulating) material. In other words, the curable composition of the present invention is preferably a thermally conductive insulating composition. For example, the volume resistivity of a thermal conductive material at 23°C and 65% relative humidity is 10 10 Preferably Ω·cm or more, 10 12 Ω·cm or more is more preferable, 10 14 A value of Ω·cm or higher is even more preferable. The upper limit is 10 18 A value of Ω·cm or less is preferable.

[0235] <Applications of thermal conductive materials> The thermal conductive material obtained using the curable composition of the present invention can be used as a heat dissipation material such as a heat dissipation sheet and can be used for heat dissipation applications in various devices. More specifically, a device with a thermal conductive layer can be fabricated by placing a thermal conductive layer containing the thermal conductive material of the present invention on a device, thereby efficiently dissipating heat generated from the device through the thermal conductive layer. The thermal conductive layer may also be a thermal conductive layer containing a thermal conductive multilayer sheet as described later. The thermal conductive material obtained using the curable composition of the present invention has sufficient thermal conductivity and high heat resistance, making it suitable for heat dissipation applications in power semiconductor devices used in various electrical equipment such as personal computers, general home appliances, and automobiles. Furthermore, since the heat-conducting material obtained using the curable composition of the present invention has sufficient heat conductivity even in a semi-cured state, it can be used as a heat dissipation material placed in areas where it is difficult to reach light for photocuring, such as gaps between components of various devices. In addition, because it has excellent adhesive properties, it can also be used as a heat-conducting adhesive.

[0236] The thermal conductive material obtained using the curable composition of the present invention may be used in combination with other components other than those formed from the curable composition. For example, a thermal conductive material (such as a thermal conductive sheet) may be combined with a support (adherend) other than the layer formed from the curable composition. Examples of support materials (adherends) include plastic materials, metal materials, or glass. Examples of plastic materials include polyester such as polyethylene terephthalate (PET), polycarbonate, acrylic resin, epoxy resin, polyurethane, polyamide, polyolefin, cellulose derivatives, and silicone. Examples of metal materials include copper and aluminum. The support (adhered material) may also preferably be in the form of a sheet. The film thickness of the sheet-like thermal conductive material (thermal conductive sheet) is preferably 100 to 300 μm, and more preferably 150 to 250 μm.

[0237] Furthermore, an adhesive layer and / or a tack layer may be combined with the thermal conductive material (preferably a thermal conductive sheet). By joining a thermal conductive material to an object to which heat should be transferred, such as a device, via such an adhesive layer and / or tack layer, a stronger bond between the thermal conductive material and the object can be achieved. The thermal conductive material formed from the curable composition of the present invention also exhibits good adhesion to the adhesive layer and tack layer, and delamination at the interface between the thermal conductive material and the adhesive layer or tack layer can be suppressed. For example, a thermally conductive multilayer sheet may be prepared, comprising a thermally conductive sheet and an adhesive layer or tack layer provided on one or both sides of the thermally conductive sheet. Furthermore, one or both sides of the thermal conductive sheet may be provided with either an adhesive layer or a tack layer, or both may be provided. One side of the thermal conductive sheet may be provided with an adhesive layer, and the other side with a tack layer. Also, one or both sides of the thermal conductive sheet may be partially or entirely provided with an adhesive layer and / or tack layer. As described above, in the present invention, the thermal conductive material such as the thermal conductive sheet may be in a semi-cured state (semi-cured film), and the thermal conductive sheet in the thermal conductive multilayer sheet may be in a semi-cured state. The adhesive layer in the thermal conductive multilayer sheet may be cured, semi-cured, or uncured. [Examples]

[0238] The present invention will be described in further detail below based on the following examples. The materials, amounts used, proportions, processing content, and processing procedures shown in the following examples can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the following examples.

[0239] <Preparation of curable composition> [Various ingredients] The various components used in the examples and comparative examples are shown below.

[0240] (Compound X and Compound Y) Compound XP-2 was synthesized according to the following scheme.

[0241] [ka]

[0242] A solution of 4-cyano-4-[(dodecylsulfanylthiocarbonylcarbonyl)sulfanyl]pentanoic acid (Tokyo Chemical Industries, Ltd., 21.9 g) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (Tokyo Chemical Industries, Ltd., 11.4 g) in dichloromethane (120 mL) was cooled to 5°C, and a silane coupling agent (X-12-5263 HP, Shin-Etsu Chemical Co., Ltd., 10.4 g) was added dropwise. The mixture was heated to room temperature and stirred for a further 2 hours. After concentrating the dichloromethane, it was purified by column chromatography, and isopropyl alcohol (IPA) was added to the resulting oily component to obtain a solution containing compound XP-2-1 (solid content 24% by mass, 75 g).

[0243] Next, M-1 (2-methoxyethyl methacrylate, 6.9 g), M-2 (maleic anhydride, 0.93 g), M-3 (4-methylstyrene, 1.49 g), and cyclopentanone (CPO, 17.6 g) were added to the solution containing the obtained compound XP-2-1 (24% solids by mass, 2.0 g), and the temperature was raised to 75°C under a nitrogen atmosphere. Then, V-601 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., 47 mg) was added, and the mixture was stirred for 10 hours while maintaining the temperature at 75°C. After confirming the disappearance of each monomer by NMR, cyclopentanone was added to obtain a 30% by mass solution of compound XP-2.

[0244] Compound YP-3 was synthesized according to the following scheme.

[0245] [ka]

[0246] Dipentaerythritol hexakis (3-mercaptopropionate) (Fujifilm Wako Pure Chemical Industries, Ltd., 14.5 g) and a silane coupling agent (KBE-1003, Shin-Etsu Chemical Co., Ltd., 10.5 g) were dissolved in cyclopentanone (CPO, 60 mL). V-601 (Fujifilm Wako Pure Chemical Industries, Ltd., 32 mg) was added to the solution and the mixture was stirred for 2 hours at 80°C under a nitrogen atmosphere. Subsequently, another 32 mg of V-601 (Fujifilm Wako Pure Chemical Industries, Ltd.) was added, and the mixture was stirred for 2 hours at 90°C under a nitrogen atmosphere. NMR confirmed the disappearance of the silane coupling agent, and the concentration was adjusted by adding cyclopentanone to obtain a cyclopentanone solution of compound YP-3-1 at 30% by mass.

[0247] M-4 was synthesized according to the following scheme.

[0248] [ka]

[0249] To a 500 mL THF / DMF=9 / 1 solution (55 g) of 5-benzotriazolecarboxylic acid (Tokyo Chemical Industries, Ltd.), 2-hydroxyethyl methacrylate (Tokyo Chemical Industries, Ltd., 20.9 g), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (Tokyo Chemical Industries, Ltd., 30.8 g), and 4-dimethylaminopyridine (Fujifilm Wako Pure Chemical Industries, Ltd., 1.9 g) were added, and the mixture was stirred for 6 hours under air at a temperature of 70°C. After the reaction was complete, distilled water (200 mL) and ethyl acetate were added, and the organic layer was extracted and concentrated to obtain M-4 (35 g).

[0250] To dimethylacetamide (DMAc, 5.4 mL), a cyclopentanone solution of 30% by mass of compound YP-3-1 (synthetic, 0.64 g), M-4 (synthetic, 5.8 g), and a dimethylacetamide solution (11.6 mL) containing V-601 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., 15 mg) was added dropwise over 2.5 hours under a nitrogen atmosphere at 80°C. After the addition was complete, the mixture was stirred for 2.5 hours. Further addition of V-601 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., 15 mg) was made, the temperature was raised to 90°C, and the mixture was stirred for a further 2 hours. A dimethylacetamide solution of 25% by mass of compound YP-3 was obtained. The monomer equivalent of compound X or compound Y refers to the amount of monomer when YP-3-1 is considered as 1 equivalent. The monomer equivalents of compound X or compound Y used in each example were as shown in the table below.

[0251] Compound XP-5 was synthesized according to the following scheme.

[0252] [ka]

[0253] Dipentaerythritol hexakis (3-mercaptopropionate) (Fujifilm Wako Pure Chemical Industries, Ltd., 4.4 g), allyl succinic anhydride (Tokyo Chemical Industries, Ltd., 2.4 g), and a silane coupling agent (KBE-1003, Shin-Etsu Chemical Co., Ltd., 3.2 g) were dissolved in cyclopentanone (CPO, 20 mL). V-601 (Fujifilm Wako Pure Chemical Industries, Ltd., 19 mg) was added to this solution and the mixture was stirred for 2 hours at 80°C under a nitrogen atmosphere. Subsequently, another 19 mg of V-601 (Fujifilm Wako Pure Chemical Industries, Ltd.) was added and the mixture was stirred for 2 hours at 90°C under a nitrogen atmosphere. NMR confirmed the disappearance of the silane coupling agent, and the concentration was adjusted by adding cyclopentanone to obtain a cyclopentanone solution of compound XP-5 at 30% by mass.

[0254] Compounds X and Y, other than those mentioned above, were synthesized using commercially available products or by referring to the synthesis method described above. Furthermore, each monomer was synthesized using commercially available products or by referring to the synthesis method described in M-4 above.

[0255] -monomer-

[0256] [ka]

[0257] -Compound X- • Compound XP-1:X-12-1287A (manufactured by Shin-Etsu Chemical Co., Ltd.) In the following equations, the subscripts in parentheses at both ends of X represent the mean value.

[0258] [ka]

[0259] [ka]

[0260] -Compound Y- • Compound YM-1:X-12-1214A (manufactured by Shin-Etsu Chemical Co., Ltd.)

[0261] In the formula, n represents the value in the "Repeating Unit n" column shown in the table below. The subscripts in parentheses at both ends of X in the formula represent the average value.

[0262] [ka]

[0263] [ka]

[0264] [ka]

[0265] [ka]

[0266] (Phenol compounds) The average value of n for compound A-3 is 1.

[0267] [ka]

[0268] (Epoxy compound) The weight-average molecular weight of B-8 is 3000, and the average value of n for B-9 is 10. * indicates the bond position.

[0269] [ka]

[0270] (Maleimide compounds) • E-1: MIR-3000-70MT, the average value of n for E-1 is 1, manufactured by Nippon Kayaku Co., Ltd. • E-2: BMI-70, manufactured by Kei-I Kasei Co., Ltd.

[0271] [ka]

[0272] (Curing accelerator)

[0273] [ka]

[0274] (Inorganic particles, modified inorganic particles) • Inorganic particles X1: PTX-60, boron nitride aggregate, particle size D 50 : 60 μm, manufactured by Momentive • Inorganic particles X2: HP-40, boron nitride aggregates, particle size D 50 : 40 μm, manufactured by Mizushima Iron Alloy Co., Ltd. • Inorganic particles X3: PCTL5MHF, boron nitride aggregates, particle size D50 : 80 μm, manufactured by Saint-Gobain • Inorganic particles X4: PT-110, flaky boron nitride, particle size D 50 : 45 μm, manufactured by Momentive • Inorganic particles X5: SGPS, boron nitride aggregates, particle size D 50 : 12 μm, manufactured by Denka Co., Ltd. • Modified inorganic particles X1: Modified boron nitride produced by manufacturing method 1 shown below. • Modified inorganic particles X2: Modified boron nitride produced by manufacturing method 2 shown below. • Modified inorganic particles X3: Modified boron nitride produced by manufacturing method 3 shown below. • Modified inorganic particles X4: Modified boron nitride produced by the manufacturing method 4 shown below. • Modified inorganic particles X5: Modified boron nitride produced by manufacturing method 5 shown below. • Modified inorganic particles X6: Modified boron nitride produced by the manufacturing method 6 shown below. • Modified inorganic particles X7: Modified boron nitride produced by the manufacturing method 7 shown below. • Modified inorganic particles X8: Modified boron nitride produced by the manufacturing method 8 shown below. • Modified inorganic particles X9: Modified boron nitride produced by the manufacturing method 9 shown below. • Modified inorganic particles X10: Modified boron nitride produced by the manufacturing method 10 shown below. • Modified inorganic particles X11: Modified boron nitride produced by the manufacturing method 11 shown below. • Modified inorganic particles X12: Modified boron nitride produced by the manufacturing method 12 shown below.

[0275] -Manufacturing method 1- Boron nitride (inorganic particles X1, 50g) was added to NaOH water (NaOH: 40g / water: 400mL) and stirred. Sodium persulfate water (sodium persulfate: 9.6g / water: 100mL) was then added to the above NaOH water, and the NaOH water was heated to 50°C and stirred for a further 3 hours (modification step). Stirring was performed at 150 rpm using a Three One Motor (manufactured by Shinto Kagaku Co., Ltd.). After cooling the above NaOH solution to room temperature, the boron nitride in the NaOH solution was filtered out, and the filtered boron nitride was washed with water (500 mL) and acetonitrile (250 mL) to obtain modified inorganic particles X1.

[0276] -Manufacturing method 2- A mixture was obtained by adding boron nitride (inorganic particles X1, 50 g) to water (400 mL) and stirring. 30% hydrogen peroxide solution (30 mL) was then added to the mixture, and the mixture was heated to 50°C and stirred for a further 3 hours. The stirring was performed using a Three One motor (manufactured by Shinto Kagaku Co., Ltd.) at 150 rpm. After the above mixture was cooled to room temperature, the boron nitride in the mixture was filtered out, and the filtered boron nitride was washed with water (500 mL) and acetonitrile (250 mL) to obtain modified inorganic particles X2.

[0277] -Manufacturing method 3- Modified inorganic particles X3 were obtained using the same method as in Manufacturing Method 1, except that the NaOH water was changed to (NaOH: 0.02 g / water: 400 mL). In addition, in manufacturing method 3, the pH of the solution (aqueous solution) obtained by mixing NaOH water (NaOH: 0.02 g / water: 400 mL), boron nitride (50 g), and sodium persulfate water (sodium persulfate: 9.6 g / water: 100 mL) was 11.

[0278] -Manufacturing method 4- In an oxygen atmosphere, boron nitride (inorganic particle X1, 50g) was heated at 1,000°C for 1 hour to obtain modified inorganic particle X4.

[0279] -Manufacturing method 5- Boron nitride (inorganic particles X2, 15g) was subjected to vacuum plasma treatment (gas type: O2, pressure: 30Pa, output: 500W) using a Plascleaner PDC210 (manufactured by Yamato Scientific Co., Ltd.). After every 5 minutes of vacuum plasma treatment, the boron nitride to be treated was stirred, and the vacuum plasma treatment was continued until the total treatment time reached 30 minutes, thereby obtaining modified inorganic particles X5.

[0280] -Manufacturing method 6- Modified particles X6 were obtained using the same method as in Manufacturing Method 1, except that boron nitride (inorganic particles X1, 50g) was replaced with boron nitride (inorganic particles X2, 50g).

[0281] -Manufacturing method 7- A mixture was obtained by adding boron nitride (inorganic particles x2, 50g) to water (400mL) and stirring. Sodium hypochlorite solution (sodium hypochlorite pentahydrate: 48g / water: 100mL) was then added to the mixture, and the mixture was heated to 50°C and stirred for a further 3 hours. Stirring was performed at 150 rpm using a Three One Motor (manufactured by Shinto Kagaku Co., Ltd.). After the above mixture was cooled to room temperature, the boron nitride in the mixture was filtered out, and the filtered boron nitride was washed with water (500 mL) and acetonitrile (250 mL) to obtain modified inorganic particles X7.

[0282] -Manufacturing method 8- Boron nitride (inorganic particles X2, 50g) was heated at 1000°C for 1 hour to obtain modified inorganic particles X8.

[0283] -Manufacturing method 9- Boron nitride (inorganic particles X2, 50g) was heated at 900°C for 4 hours to obtain modified inorganic particles X9.

[0284] -Manufacturing method 10- Modified inorganic particles X10 were obtained using the same method as in Manufacturing Method 1, except that boron nitride (inorganic particles X1, 50g) was replaced with boron nitride (inorganic particles X3, 50g).

[0285] -Manufacturing method 11- Modified inorganic particles X11 were obtained using the same method as in Manufacturing Method 1, except that boron nitride (inorganic particles X1, 50g) was replaced with boron nitride (inorganic particles X4, 50g).

[0286] -Manufacturing method 12- Modified particle X12 was obtained using the same method as in manufacturing method 1, except that boron nitride (particle X1, 50g) was replaced with boron nitride (particle X5, 50g).

[0287] (Other compounds) • X-12-967C: Manufactured by Shin-Etsu Chemical Co., Ltd. • KBM-403: Manufactured by Shin-Etsu Chemical Co., Ltd.

[0288] [Preparation of curable composition: Examples] (Manufacturing method A) The curable composition of Example 17 was obtained by following the procedure (Manufacturing Method A). To the obtained 25% by mass solution (6.3 g) of compound YP-3, isopropyl alcohol (3.3 g), distilled water (1.2 g), and acetic acid (0.3 g) were added, and the mixture was stirred at room temperature for 1 hour to obtain a hydrolysis solution of compound YP-3. Next, 200g of modified inorganic particles X1 were added to 400mL of acetonitrile, and then a hydrolysis solution of compound YP-3 was added and the mixture was stirred for 1 hour. After filtering out the modified inorganic particles X1 surface-modified with each compound YP-3 in the acetonitrile, the mixture was washed with 40mL of acetonitrile and dried in an oven at 40°C, thereby surface-modifying the modified inorganic particles X1 with compound YP-3 and the like. Next, as shown in the table below, the phenol compound, epoxy compound, maleimide compound, and curing accelerator were mixed in that order, and then modified inorganic particles X1 surface-modified with compound YP-3 were added. The resulting mixture was treated for 5 minutes in a rotary-orbit mixer (THINKY, Awatori Rentaro ARE-310) to obtain the curable composition of Example 17. Manufacturing method A is a method for producing a curable composition that meets requirement 1 or requirement 3.

[0289] (Manufacturing method B) The curable composition of Example 46 was obtained by following the procedure below (Manufacturing Method B). As shown in the table below, a solution of 25% by mass of compound YP-3 (6.3 g), a phenol compound, an epoxy compound, a maleimide compound, and a curing accelerator were mixed in that order, and then modified inorganic particles X1 were added. The resulting mixture was treated for 5 minutes in a rotary-orbit mixer (THINKY, Awatori Rentaro ARE-310) to obtain the curable composition of Example 46. Manufacturing method B is a method for producing a curable composition that meets requirement 2 or requirement 4.

[0290] Other curable compositions not listed above were manufactured using the above manufacturing method as a reference, so as to have the configurations shown in the table. In Examples 116 to 119, the curable compositions used were compound XP-5 and other compound X-12-967C in a 1:1 (mass ratio).

[0291] [Comparative Example 1] As shown in the table below, a phenol compound, an epoxy compound, a maleimide compound, and a curing accelerator were mixed in that order, and then inorganic particles X1 were added. The resulting mixture was treated for 5 minutes in a rotary-orbit mixer (THINKY, Awatori Rentaro ARE-310) to obtain the curable composition of Comparative Example 1.

[0292] [Comparative Example 2] A curable composition of Comparative Example 2 was obtained using the same procedure as for the curable composition of Example 1, except that the modified inorganic particles X1 were surface-modified with a silane coupling agent having one epoxy group (molecular weight 236, KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) instead of compound XP-1, and that the maleimide compound was not included.

[0293] The amount of solvent added to each curable composition was set to an amount that resulted in a solid content concentration of 50-80% by mass for each curable composition. The solid content concentration of each curable composition was adjusted within the above range so that the viscosity of each curable composition was approximately the same. As the solvents mentioned above, solvents used in the preparation of various components were used as appropriate. The total content of epoxy compounds and phenolic compounds was adjusted so that it equaled the amount shown in the "Total Amount (mass%)" column of the table relative to the total solid content of the curable composition, and the amounts of epoxy compounds and phenolic compounds added were equivalent (the amount in which the number of epoxy groups in the epoxy compound is equal to the number of hydroxyl groups in the phenolic compound). In the curable composition, the amounts of maleimide compound, curing accelerator, and inorganic particles were set to the amounts (mass %) shown in parentheses in each column of the table, relative to the total solid content of the curable composition.

[0294] <Rating> [Preparation of semi-cured sheets (semi-cured films)] Using a micrometer-equipped applicator, the prepared curable composition was uniformly applied to the release surface of a release-treated PET film (PET756501, manufactured by Lintec Corporation, film thickness 75 μm), and dried at 120°C for 4 minutes to produce a semi-cured sheet (semi-cured film).

[0295] [Fabrication of thermal conductive sheets] A release-treated PET film was placed on the surface of the obtained semi-cured sheet opposite to the PET film, and it was hot-pressed under air (hot plate temperature 180°C, pressure 5-20 MPa for 5 minutes). Then, it was heat-treated at 180°C for 90 minutes under normal pressure to obtain a resin sheet. The PET films on both sides of the resin sheet were peeled off to obtain a thermal conductive sheet (thermal conductive material) with an average film thickness of 120 μm.

[0296] [Evaluation of thermal conductivity] (1) The thermal diffusivity in the thickness direction of the thermal conductive sheet was measured using the laser flash method with the "LFA467" manufactured by NETZSCH. (2) The specific gravity of the thermal conductive sheet was measured using the Archimedes method (using a "solid specific gravity measurement kit") with a Mettler-Toledo balance "XS204". (3) Using the "DSC320 / 6200" manufactured by Seiko Instruments, the specific heat of the thermal conductive sheet at 25°C was determined under a heating condition of 10°C / min. (4) The thermal conductivity of the thermal conductive sheet was calculated by multiplying the obtained thermal diffusivity by the specific gravity and specific heat. The thermal conductivity of the thermal conductive sheets was classified according to the following criteria, and the thermal conductivity of the thermal conductive sheets obtained using the compositions of each example or comparative example was evaluated. A: 18W / mK or more B: 15W / mK or more and less than 18W / mK C: 12W / mK or higher, less than 15W / mK D: Less than 12W / mK

[0297] [Copper foil peel strength (adhesion)] The PET film was peeled off the obtained semi-cured sheet, and the resulting semi-cured sheet was cut into 20mm x 60mm strips and sandwiched between the adherends: electrolytic copper foil (20mm x 100mm, 35μm thick) and an aluminum plate (30mm x 60mm, 1mm thick). The resulting laminate was then subjected to a hot press treatment under air (treatment at a hot plate temperature of 180°C and a pressure of 20MPa for 5 minutes, followed by treatment at a hot plate temperature of 180°C and atmospheric pressure for 90 minutes) to obtain an aluminum base substrate with copper foil in which the thermal conductive sheet and adherends were integrated. The copper foil peel strength of the obtained copper foil-coated aluminum base substrates was measured using a digital force gauge (ZTS-200N, manufactured by IMADA Corporation) and a 90° peel test fixture (P90-200N-BB, manufactured by IMADA Corporation) in accordance with the measurement method for peel strength under normal conditions described in JIS C 6481. In the peel strength test, the copper foil was peeled at a 90° angle to the copper foil-coated aluminum base substrate at a peeling speed of 50 mm / min. The obtained copper foil peel strengths were evaluated by classifying them according to the following criteria. AA:6N / cm or more A: 5N / cm or more and less than 6N / cm B: 4N / cm or more and less than 5N / cm C: 3N / cm or more and less than 4N / cm D: Less than 3N / cm

[0298] [Evaluation of solder heat resistance] After peeling the PET film from the obtained semi-cured sheet, it was sandwiched between a 2 mm thick copper substrate and a 0.15 mm thick copper foil, and then heat-pressed under air (heat plate temperature 180°C, pressure 20 MPa for 5 minutes) to obtain a laminate having the structure of "copper substrate-thermal conductive sheet-copper foil". A 0.15 mm copper foil in the laminate was etched into a 2 cm diameter circular shape, and the laminate was prepared as a sample for solder heat resistance testing, having the configuration of "copper substrate - thermal conductive sheet - 2 cm diameter circular copper foil". The above sample was subjected to a heat treatment 1 to 3 times, in which it was heated at 300°C for 5 minutes and then cooled to room temperature (25°C). After that, a circular copper foil with a diameter of 2 cm was peeled off from the sample that had undergone the 1 to 3 heat treatments. The fracture state of the detached sample was visually observed. If cohesive failure of the thermal conductive sheet occurred across the entire detached surface, the sample was deemed acceptable. If interfacial delamination occurred in part or across the entire surface between the "copper substrate and thermal conductive sheet" and / or between the "thermal conductive sheet and a 2cm diameter circular copper foil," the sample was deemed unacceptable. Based on the relationship between pass / fail and pass / fail in relation to the number of heat treatments, the solder heat resistance of the thermal conductive sheets was evaluated according to the following categories. A: It passed even after being subjected to heat treatment three times. B: It passed after two heat treatments, but failed after a third. C: It passed after one heat treatment, but failed after two treatments. D: Failed after one heat treatment.

[0299] <Result> The evaluation results are shown in the table. "Content (mass%)" indicates the content of inorganic particles relative to the total solid content of the curable composition. If the composition is surface-modified with compound X, compound Y, etc., the content of the surface-modified inorganic particles is indicated. The "Manufacturing Method" column indicates that the curable composition was manufactured using manufacturing method A if it is "A," and that the curable composition was manufactured using manufacturing method B if it is "B." The "Particle X or Modified Particle X" column indicates the type of inorganic particle used. For example, "Modified Particle X1" refers to modified inorganic particle X1, and "Particle X1" refers to inorganic particle X1. The "Group or Ring" column indicates the group or ring present in compound X, compound Y, or other compounds. In the "Structure of the central part" column, in equation (X-1) or equation (Y-1), A X Or A Y This shows the structure of a polyvalent linking group represented by . The "Number of branches in the central part" column is A above. X Or A Y This indicates the valence of the structure of the polyvalent linking group represented by . The "Number of Alkoxysilyl Groups" column indicates the number of alkoxysilyl groups present in compound X or compound Y. The above number is an average value. The "Monomer Equivalent" column is as described above. The "Repeating Units" column indicates the amount (degree of polymerization) of repeating units of the monomer used. When multiple types of monomers are used, the sum of the amounts (degrees of polymerization) of repeating units derived from the multiple types of monomers is the value shown in the "Repeating Units" column. In other words, in Example 3, the sum of the amount of repeating units n1 derived from monomer 1, the amount of repeating units n2 derived from monomer 2, and the amount of repeating units n3 derived from monomer 3 (n1 + n2 + n3) is 50. The "Monomer 1-3" column shows the monomers used and their amounts (parts by mass).

[0300] [Table 1]

[0301] [Table 2]

[0302] [Table 3]

[0303] [Table 4]

[0304] [Table 5]

[0305] [Table 6]

[0306] [Table 7]

[0307] [Table 8]

[0308] The results shown in the table confirm that the curable composition can obtain the effects of the present invention. Comparative Examples 1 and 2 did not satisfy any of requirements 1 to 4, and therefore the desired effects could not be obtained. It was confirmed that compound X exhibits superior peel strength when it has a repeating unit represented by formula (x-3) or formula (x-4) (Examples 1-4, 13). It was confirmed that the peel strength is superior when compound Y has two or more specific aromatic heterocycles (Examples 14, 15-34). When the curable composition was manufactured using manufacturing method A (satisfying requirement 1 or requirement 3), it was confirmed that it exhibited superior thermal conductivity (Examples 17 and 46). It was confirmed that when the inorganic particles are surface-treated inorganic particles, the thermal conductivity is superior (Examples 17 and 47). It was confirmed that when the epoxy compound contains at least one of a rod-shaped compound and a disc-shaped compound, at least one of the following properties is superior: thermal conductivity, peel strength, and solder heat resistance (Examples 17 and 49-102). It was confirmed that when the maleimide compound content is 3.5 to 8% by mass relative to the total solid content of the curable composition, at least one of the thermal conductivity, peel strength, and solder heat resistance is superior (Examples 17, 107, and 108). It was confirmed that when the curable composition contains a maleimide compound, the thermal conductivity and solder heat resistance are superior (Examples 17 and 111).

Claims

1. A curable composition comprising a curable compound and inorganic particles, The inorganic particles are selected from the group consisting of inorganic nitride particles and inorganic oxide particles. A curable composition that satisfies at least one of requirements 1 or 2. Requirement 1: The inorganic particles are surface-modified with at least one selected from the group consisting of compounds having one or more acid anhydride groups and two or more alkoxysilyl groups, their hydrolysates, and their hydrolysate condensates. Requirement 2: The curable composition comprises at least one selected from the group consisting of compounds having one or more acid anhydride groups and two or more alkoxysilyl groups, hydrolysates thereof, and hydrolyzed condensates thereof. However, the compound having one or more acid anhydride groups and two or more alkoxysilyl groups has a group represented by any of the following formulas (x-1-1) to (x-1-3) as the acid anhydride group, The compound having one or more acid anhydride groups and two or more alkoxysilyl groups has a repeating unit represented by any of formulas (x-3) to (x-4). 【Chemistry 1】 In formula (x-1-1), R ｘ１１ ~R ｘ１４ Each of these independently represents a hydrogen atom, a substituent, or a bond position. However, R ｘ１１ ~R ｘ１４ Of these, only one represents the joining position. In formula (x-1-2), R ｘ２１ and R ｘ２２ Each of these independently represents a hydrogen atom, a substituent, or a bond position. However, R ｘ２１ and R ｘ２２ Of these, only one represents the joining position. In formula (x-1-3), * represents a bond position. W represents a ring which may have substituents. m represents 1. n represents a non-negative integer. 【Chemistry 2】 In formula (x-3), R x1 represents a hydrogen atom or a methyl group. L x1 represents a single bond or a divalent linking group. In formula (x-4), R x2 represents a hydrogen atom or a methyl group. L x2 represents a single bond or a divalent linking group. Ar represents an aromatic ring which may have substituents.

2. The curable composition according to claim 1, wherein the inorganic particles are boron nitride particles or aggregates thereof.

3. Furthermore, the curable composition according to claim 1 or 2, comprising an epoxy compound.

4. Furthermore, the curable composition according to any one of claims 1 to 3, comprising a phenol compound.

5. The curable compound comprises an epoxy compound and a phenol compound. The curable composition according to any one of claims 1 to 4, wherein the phenol compound has 3 to 7 hydroxyl groups in its molecule.

6. The curable compound comprises an epoxy compound and a phenol compound. The curable composition according to any one of claims 1 to 5, wherein the epoxy compound has a triazine skeleton, and the phenol compound has a triazine skeleton.

7. Furthermore, the curable composition according to any one of claims 1 to 6, comprising a curing accelerator.

8. The curable composition according to claim 7, wherein the curing accelerator comprises a compound containing a phosphorus atom.

9. A thermal conductive material obtained by curing a curable composition according to any one of claims 1 to 8.

10. A heat-conducting sheet made of the heat-conducting material described in claim 9.

11. A device with a thermal conductive layer, comprising a device and a thermal conductive layer comprising a thermal conductive sheet according to claim 10 disposed on the device.

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