Composition containing compound having polyoxyalkylene chain and acrylic copolymer

Abstract

A composition containing: a compound represented by formula (1); and a copolymer containing, as monomer units, a methyl (meth) acrylate and an alkyl (meth) acrylate having a C2-12 alkyl group, in formula (1), R11 and R12 each independently represent a hydrogen atom or a methyl group, and R13 represents a divalent group having a polyoxyalkylene chain, with the total amount of the monomer units contained in the copolymer as a reference, the content of the monomer units contained in the copolymer being less than or equal to 1%. The content of methyl (meth) acrylate is 25 mass% or more. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a composition containing a compound having a polyoxyalkylene chain and an acrylic copolymer. Background Art

[0002] Electronic parts such as processors, power modules, and batteries for electric vehicles generate heat during use. In order to protect such parts from heat, a mechanism that efficiently dissipates the generated heat is required. A thermally conductive material (sometimes also called a heat sink) called a thermal interface material (TIM) is a material that is disposed between a heat source and a heat sink or other heat dissipation component to reduce the thermal resistance between the heat source and the heat dissipation component and promote heat conduction from the heat source. The heat generated from the heat source is efficiently conducted to the cooling component via the TIM, so it is easy to dissipate heat from the heat dissipation component.

[0003] As thermally conductive materials, many liquid materials also called heat dissipation grease or thermally conductive grease are known. However, when using liquid thermally conductive grease, there may be a phenomenon in which the grease is squeezed out from between the parts due to dripping after application or deformation of the parts coated with the thermally conductive grease. In order to solve such a problem, a thermally conductive material formed into a solid state such as a sheet is sometimes used. The solid thermally conductive material is obtained by curing a composition containing a polymerizable compound in addition to a thermally conductive filler, for example.

[0004] Patent Document 1 discloses that a curable composition containing a specific compound having a polyoxyalkylene chain and two (meth)acryloyl groups has been found to have excellent elongation in a cured product and that the curable composition can be suitably used as a thermally conductive material by containing a thermally conductive filler.

[0005] Previous technical literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2021 / 107001 Summary of the invention

[0008] Technical issues to be solved by the invention

[0009] An object of one aspect of the present invention is to provide a composition containing a specific compound having a polyoxyalkylene chain and two (meth)acryloyl groups, wherein the composition can form a cured product having excellent breaking strength.

[0010] Means for solving technical problems

[0011] As a result of diligent research, the present inventors have found that in a composition containing a specific compound having a polyoxyalkylene chain and two (meth)acryloyl groups as described in Patent Document 1, by further containing an acrylic copolymer containing a specific (meth)acrylate as a monomer unit, a cured product having excellent breaking strength can be obtained. It is also clearly known that when the copolymerization ratio in the acrylic copolymer is within a specific range, the compatibility of the compound having a polyoxyalkylene chain and two (meth)acryloyl groups with the acrylic copolymer becomes good, and a composition that can suitably form a cured product as described above can be prepared. The present invention provides the following [1] to [6] in several aspects.

[0012] [1] A composition comprising:

[0013] A compound represented by the following formula (1); and

[0014] A copolymer comprising, as monomer units, methyl (meth)acrylate and an alkyl (meth)acrylate having an alkyl group having 2 to 12 carbon atoms,

[0015]

[0016] [In formula (1), R 11 and R 12 Each independently represents a hydrogen atom or a methyl group, R 13 It represents a divalent group having a polyoxyalkylene chain.]

[0017] In the above composition,

[0018] The content of methyl (meth)acrylate is 25% by mass or more based on the total amount of monomer units contained in the copolymer.

[0019] [2] The composition according to [1], further comprising a thermally conductive filler.

[0020] [3] The composition according to [1] or [2], further comprising a compound represented by the following formula (2).

[0021]

[0022] [In formula (2), R 21 and R 22 Each independently represents a hydrogen atom or a monovalent organic group, and may be bonded to each other to form a ring, R 23 represents a hydrogen atom or a methyl group.]

[0023] [4] The composition according to any one of [1] to [3], further comprising a compound represented by the following formula (3).

[0024]

[0025] [In formula (3), R 31 and R 32 Each independently represents a hydrogen atom or a methyl group, R 33 It represents a divalent group having a poly(meth)acrylate chain.]

[0026] [5] A cured product, which is a cured product of the composition according to any one of [1] to [4].

[0027] [6] An article comprising: a heat source; and the cured product according to [5] in thermal contact with the heat source.

[0028] Effects of the Invention

[0029] According to one aspect of the present invention, there is provided a composition containing a specific compound having a polyoxyalkylene chain and two (meth)acryloyl groups, wherein the composition can form a cured product having excellent breaking strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic cross-sectional view showing one embodiment of the article.

[0031] Figure 2 It is a schematic cross-sectional view showing another embodiment of the article. DETAILED DESCRIPTION

[0032] Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

[0033] The term "(meth)acryloyl" in the present specification refers to "acryloyl" and its corresponding "methacryloyl", and the same also applies to similar expressions such as "(meth)acrylate" and "(meth)acrylic acid".

[0034] The weight average molecular weight (Mw) and the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn) in this specification refer to values ​​determined by measuring using gel permeation chromatography (GPC) under the following conditions and using polystyrene as a standard substance.

[0035] · Measurement equipment: HLC-8320GPC (product name, manufactured by TOSOH CORPORATION)

[0036] Analytical column: TSKgel SuperMultipore HZ-H (3 connected) (product name, manufactured by TOSOH CORPORATION)

[0037] Guard column: TSK guardcolumn SuperMP (HZ) -H (product name, manufactured by TOSOH CORPORATION)

[0038] ·Eluent: THF

[0039] ·Measurement temperature: 25℃

[0040] The composition according to one embodiment of the present invention contains a compound represented by the following formula (1).

[0041]

[0042] In formula (1), R 11 and R 12 Each independently represents a hydrogen atom or a methyl group, R 13 It represents a divalent group having a polyoxyalkylene chain.

[0043] In one embodiment, R 11 and R 12 One of them may be a hydrogen atom and the other may be a methyl group. In another embodiment, R 11 and R 12 Both of them can be hydrogen atoms. In another embodiment, R 11 and R 12 Both of these may be methyl groups.

[0044] In one embodiment, the polyoxyalkylene chain includes a structural unit represented by the following formula (1a). This can suppress an excessive increase in the viscosity of the composition and further improve the strength of the cured product.

[0045]

[0046] At this time, R 13 It may be a divalent group having a polyoxyethylene chain, and the compound represented by the formula (1) is preferably a compound represented by the following formula (1-2) (polyethylene glycol di(meth)acrylate).

[0047]

[0048] In formula (1-2), R 11 and R 12 Respectively with R in formula (1) 11 and R 12 The meanings are the same, and m is an integer greater than 2.

[0049] In another embodiment, the polyoxyalkylene chain includes a structural unit represented by the following formula (1b): This allows easy handling of the composition.

[0050]

[0051] At this time, R 13 It may be a divalent group having a polyoxypropylene chain, and the compound represented by the formula (1) is preferably a compound represented by the following formula (1-3) (polypropylene glycol di(meth)acrylate).

[0052]

[0053] In formula (1-3), R 11 and R 12 Respectively with R in formula (1) 11 and R 12 The meanings are the same, and n is an integer greater than 2.

[0054] In another embodiment, from the viewpoint of easily taking into account the strength of the cured product of the compound represented by formula (1) and the easy handling of the composition, the polyoxyalkylene chain is preferably a copolymer chain comprising the structural unit represented by formula (1a) and the structural unit represented by formula (1b). The copolymer chain may be any of an alternating copolymer chain, a block copolymer chain or a random copolymer chain. From the viewpoint of further reducing the crystallinity of the compound represented by formula (1) and being able to further easily handle the composition, the copolymer chain is preferably a random copolymer chain.

[0055] In the above-mentioned embodiments, the polyoxyalkylene chain may have an oxyalkylene group having 4 to 5 carbon atoms such as oxytetramethylene, oxybutenyl, or oxypentenyl as a structural unit in addition to the structural unit represented by formula (1a) and the structural unit represented by formula (1b).

[0056] R 13 It may be a divalent group having other organic groups in addition to the above-mentioned polyoxyalkylene chain. The other organic groups may be chain groups other than the polyoxyalkylene chain, for example, a methylene chain (with -CH 2 - as a structural unit), a polyester chain (a chain containing -COO- in a structural unit), a polyurethane chain (a chain containing -OCON- in a structural unit), and the like.

[0057] For example, the compound represented by formula (1) may be a compound represented by the following formula (1-4).

[0058]

[0059] In formula (1-4), R 11 and R 12 Respectively with R in formula (1) 11 and R 12 Same meaning, R 14 and R 15Each of k1, k2 and k3 is independently an alkylene group having 2 to 5 carbon atoms, and each of k1, k2 and k3 is independently an integer greater than 2. For example, k2 may be an integer less than 16.

[0060] There are plural R 14 and R 15 They may be the same or different from each other. 14 and R 15 Preferably, they contain ethylene and propylene, respectively. 14 O) k1 The polyoxyalkylene chain represented by (R 15 O) k3 The polyoxyalkylene chains represented by are preferably copolymer chains containing an oxyethylene group (a structural unit represented by the above formula (1a)) and an oxypropylene group (a structural unit represented by the above formula (1b)).

[0061] In each of the above-mentioned embodiments, the number of oxyalkylene groups in the polyoxyalkylene chain is preferably 100 or more. If the number of oxyalkylene groups in the polyoxyalkylene chain is 100 or more, the main chain of the compound represented by formula (1) becomes longer, thereby further improving the elongation of the cured product and further improving the strength of the cured product. The number of oxyalkylene groups corresponds to m in formula (1-2), n in formula (1-3), and k1 and k3 in formula (1-4), respectively.

[0062] The number of oxyalkylene groups in the polyoxyalkylene chain is more preferably 130 or more, 180 or more, 200 or more, 220 or more, 250 or more, 270 or more, 300 or more, or 320 or more. The number of oxyalkylene groups in the polyoxyalkylene chain may be 600 or less, 570 or less, or 530 or less.

[0063] From the viewpoint of lower elasticity and excellent elongation of the cured product, the weight average molecular weight of the compound represented by formula (1) is preferably 5000 or more, 6000 or more, 7000 or more, 8000 or more, 9000 or more, 10000 or more, 11000 or more, 12000 or more, 13000 or more, 14000 or more, or 15000 or more. From the viewpoint of easy adjustment of the viscosity of the composition, the weight average molecular weight of the compound represented by formula (1) is preferably 100000 or less, 80000 or less, 60000 or less, 34000 or less, 31000 or less, or 28000 or less.

[0064] The compound represented by formula (1) may be in liquid form at 25°C. In this case, from the viewpoint of facilitating application of the composition to the coating surface and improving the adhesion of the cured product to the coating surface, the viscosity of the compound represented by formula (1) at 25°C is preferably 1000 Pa·s or less, 800 Pa·s or less, 600 Pa·s or less, 500 Pa·s or less, 350 Pa·s or less, 300 Pa·s or less, or 200 Pa·s or less. The viscosity of the compound represented by formula (1) at 25°C may be 0.1 Pa·s or more, 0.2 Pa·s or more, 0.3 Pa·s or more, 1 Pa·s or more, 2 Pa·s or more, or 3 Pa·s or more.

[0065] The compound represented by formula (1) may be solid at 25°C. In this case, from the viewpoint of improving the handleability of the composition, the compound represented by formula (1) is preferably liquid at 50°C. Furthermore, from the viewpoint of further improving the handleability of the composition, the viscosity of the compound represented by formula (1) at 50°C is preferably 100 Pa·s or less, more preferably 50 Pa·s or less, further preferably 30 Pa·s or less, and particularly preferably 20 Pa·s or less. The viscosity of the compound represented by formula (1) at 50°C may be 0.1 Pa·s or more, 0.2 Pa·s or more, or 0.3 Pa·s or more.

[0066] In this specification, viscosity refers to a value measured in accordance with JIS Z8803, specifically, a value measured by an E-type viscometer (e.g., PE-80L manufactured by TOKI SANGYO CO., LTD.). In addition, the calibration of the viscometer can be performed in accordance with JIS Z8809-JS14000. The viscosity of the compound represented by formula (1) can be adjusted by adjusting the weight average molecular weight of the compound.

[0067] From the viewpoint of better elongation of the cured product, the content of the compound represented by formula (1) is preferably 1% by mass or more, 1.2% by mass or more, or 1.3% by mass or more, based on the total amount of the composition, and can be, for example, 5% by mass or less, 4% by mass or less, 3% by mass or less, or 2% by mass or less.

[0068] The composition contains a compound represented by formula (1) as a polymerizable compound, and in one embodiment, may further contain a compound represented by formula (2), may further contain a compound represented by formula (3), and may further contain other polymerizable compounds other than the compound represented by formula (1), the compound represented by formula (2), and the compound represented by formula (3) (details will be described later). From the viewpoint of better elongation of the cured product, the content of the compound represented by formula (1) is preferably 5 parts by mass or more, 7 parts by mass or more, 10 parts by mass or more, 15 parts by mass or more, or 20 parts by mass or more, and for example, may be 60 parts by mass or less, 55 parts by mass or less, 50 parts by mass or less, 45 parts by mass or less, or 40 parts by mass or less, relative to 100 parts by mass of the total of the compound represented by formula (1), the compound represented by formula (2), the compound represented by formula (3), and other polymerizable compounds contained as needed (hereinafter referred to as "the total content of the polymerizable components").

[0069] The composition of one embodiment of the present invention contains, in addition to the compound represented by formula (1), a copolymer (hereinafter also referred to as an "acrylic copolymer") containing, as monomer units, methyl (meth)acrylate and an alkyl (meth)acrylate having an alkyl group having 2 to 12 carbon atoms (hereinafter also referred to as a "C2-C12 alkyl (meth)acrylate").

[0070] The content of methyl (meth)acrylate contained in the acrylic copolymer is 25% by mass or more based on the total amount of monomer units contained in the acrylic copolymer (hereinafter, also referred to as "total amount of monomer units"). The content of methyl (meth)acrylate can be 27% by mass or more, 30% by mass or more, or 35% by mass or more, or 70% by mass or less, 60% by mass or less, 50% by mass or less, or 45% by mass or less based on the total amount of monomer units.

[0071] The number of carbon atoms in the alkyl group of the C2-C12 (meth)acrylic acid alkyl ester may be 3 or more, 8 or less, 7 or less, or 6 or less. The alkyl group may be linear, branched, or cyclic.

[0072] Specific examples of the case where the alkyl group in the C2-C12 (meth)acrylic acid alkyl ester is linear include ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, octyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, and lauryl (meth)acrylate. Specific examples of the case where the alkyl group in the C2-C12 (meth)acrylic acid alkyl ester is branched include isopropyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, isobutyl (meth)acrylate, isopentyl (meth)acrylate, isohexyl (meth)acrylate, isoheptyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, and isodecyl (meth)acrylate. As a specific example of the case where the alkyl group in the C2-C12 (meth)acrylic acid alkyl ester is cyclic (cycloalkyl), cyclohexyl (meth)acrylate can be mentioned.

[0073] The above-mentioned C2-C12 alkyl (meth)acrylates can be used alone or in combination of two or more.

[0074] The content of C2-C12 (meth)acrylic acid alkyl ester contained in the acrylic copolymer can be 40% by mass or more, 50% by mass or more, 55% by mass or more, or 60% by mass or less, based on the total amount of monomer units.

[0075] The acrylic copolymer may contain only methyl (meth)acrylate and C2-C12 alkyl (meth)acrylate as monomer units, or may contain other monomer units copolymerizable with methyl (meth)acrylate and C2-C12 alkyl (meth)acrylate. Examples of other monomer units include carboxyl group-containing monomers, hydroxyl group-containing monomers, isocyanate group-containing monomers, amino group-containing monomers, and epoxy group-containing monomers.

[0076] Examples of carboxyl-containing monomers include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, isocrotonic acid, etc. Examples of hydroxyl-containing monomers include 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, and 12-hydroxylauryl (meth)acrylate.

[0077] Examples of the isocyanate group-containing monomer include 2-methacryloyloxyethyl isocyanate, 2-acryloyloxyethyl isocyanate, etc. Examples of the amino group-containing monomer include N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, and N,N-diethylaminopropyl (meth)acrylate.

[0078] Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate, α-ethyl glycidyl (meth)acrylate, α-n-propyl glycidyl (meth)acrylate, α-n-butyl glycidyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, 4,5-epoxypentyl (meth)acrylate, 6,7-epoxyheptyl (meth)acrylate, α-ethyl (meth)acrylate-6,7-epoxyheptyl, 3-methyl-3,4-epoxybutyl (meth)acrylate, 4-methyl-4,5-epoxypentyl (meth)acrylate, 5-methyl-5,6-epoxyhexyl (meth)acrylate, β-methylglycidyl (meth)acrylate, and α-ethyl (meth)acrylate-β-methylglycidyl.

[0079] The content of other monomer units may be 10% by mass or less, 5% by mass or less, 3% by mass or less, or 1% by mass or less, based on the total amount of monomer units.

[0080] The acrylic copolymer may be an alternating copolymer, a block copolymer or a random copolymer comprising a methyl (meth)acrylate unit, a C2-C12 alkyl (meth)acrylate unit and other monomer units as required, and is preferably a block copolymer.

[0081] The block copolymer may have a block containing a methyl (meth)acrylate unit (hereinafter, also referred to as a "first block") and a block containing a C2-C12 alkyl (meth)acrylate (hereinafter, also referred to as a "second block").

[0082] The content of methyl (meth)acrylate contained in the first block may be 90% by mass or more, 95% by mass or more, or 99% by mass or more, based on the total amount of monomer units contained in the first block. For example, the first block may be a polymethyl (meth)acrylate block containing only methyl (meth)acrylate as a monomer unit.

[0083] The content of C2-C12 (meth) alkyl acrylate contained in the second block may be 90% by mass or more, 95% by mass or more, or 99% by mass or more, based on the total amount of monomer units contained in the second block. The second block may contain one selected from C2-C12 (meth) alkyl acrylates as a monomer unit, or may contain two or more. For example, the second block may be a poly (meth) acrylate n-butyl ester block containing only n-butyl (meth) acrylate as a monomer unit.

[0084] The block copolymer may be a diblock copolymer in which a first block and a second block are bonded in sequence, or may be a triblock copolymer in which a first block, a second block and a first block are bonded in sequence.

[0085] The content of the acrylic copolymer may be 0.05 mass % or more, 0.1 mass % or more, or 0.15 mass % or less, or 1 mass % or less, 0.5 mass % or less, or 0.3 mass % or less, based on the total amount of the composition.

[0086] The content of the acrylic copolymer may be 1 part by mass or more, 2 parts by mass or more, or 3 parts by mass or more, or 10 parts by mass or less, 7 parts by mass or less, or 5 parts by mass or less, based on 100 parts by mass of the total content of the polymerizable components.

[0087] The content of the acrylic copolymer may be 5 parts by mass or more, 7 parts by mass or more, 10 parts by mass or more, or 13 parts by mass or more, or 40 parts by mass or less, 30 parts by mass or less, or 25 parts by mass or less, relative to 100 parts by mass of the compound represented by formula (1).

[0088] The composition may further contain a thixotropic agent. The thixotropic agent is preferably an ester-based thixotropic agent containing an ester compound. The thixotropic agent may be in a liquid state at 25°C.

[0089] The ester-based thixotropic agent may include at least one selected from the group consisting of phosphoric acid esters, fatty acid esters, and aromatic esters.

[0090] The phosphoric acid ester may be a polyether phosphoric acid ester. Examples of the polyether phosphoric acid ester include polyoxyethylene alkyl ether phosphoric acid ester, polyoxyethylene alkylphenyl ether phosphoric acid ester, and higher alcohol phosphoric acid ester.

[0091] Examples of commercially available products of the ester-based thixotropic agent include DISPARLON 3500 (manufactured by Kusumoto Chemicals, Ltd.), Flowon RCM-100 (manufactured by KYOEISHA CHEMICAL Co., Ltd.), and BYK-R606 (manufactured by BYK Japan KK).

[0092] The above-mentioned thixotropic agent (preferably an ester-based thixotropic agent) can be used alone or in combination of two or more.

[0093] The content of the thixotropic agent (preferably an ester thixotropic agent) may be 0.01 mass % or more, 0.02 mass % or more, or 0.03 mass % or less, or 0.5 mass % or less, 0.3 mass % or less, or 0.1 mass % or less, based on the total amount of the composition.

[0094] The content of the thixotropic agent (preferably an ester thixotropic agent) may be 0.1 parts by mass or more, 0.3 parts by mass or more, or 0.5 parts by mass or less, or 5 parts by mass or less, or 4 parts by mass or less, or 3 parts by mass or less, relative to 100 parts by mass of the total content of the polymerizable components.

[0095] The content of the thixotropic agent (preferably an ester-based thixotropic agent) may be 1 part by mass or more, 2 parts by mass or more, or 3 parts by mass or less, or 10 parts by mass or less, 8 parts by mass or less, or 5 parts by mass or less, relative to 100 parts by mass of the compound represented by formula (1).

[0096] The composition may further contain a compound represented by the following formula (2).

[0097]

[0098] In formula (2), R 21 and R 22 R each independently represents a hydrogen atom or a monovalent organic group, and may be bonded to each other to form a ring. 23 represents a hydrogen atom or a methyl group.

[0099] In one embodiment, R 21 and R 22 One of them may be a hydrogen atom, and the other may be a monovalent organic group. 21 and R 22 Both of them can be hydrogen atoms. In another embodiment, R 21 and R 22 These two may be monovalent organic groups which may bond to each other to form a ring.

[0100] In R 21 and R 22 When the monovalent organic group is not bonded to form a ring, it can be, for example, a monovalent hydrocarbon group or an alkyl group. The number of carbon atoms in the monovalent hydrocarbon group (for example, an alkyl group) can be, for example, 1 or more, or 6 or less. Examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, and the like. 21 and R 22Examples of the compound represented by the formula (2) when the two groups are not bonded to form a ring include dimethylacrylamide, diethylacrylamide and diisopropylacrylamide.

[0101] R 21 and R 22 Preferably, they are bonded to each other to form a ring. In this case, the ring can be, for example, a 5-membered ring, a 6-membered ring or a 7-membered ring, preferably a 6-membered ring. The ring is composed of the nitrogen atom in formula (2) and R 21 and R 22 The ring may contain carbon atoms, hydrogen atoms, oxygen atoms, sulfur atoms, etc. in addition to the nitrogen atom, and preferably contains only carbon atoms, hydrogen atoms and oxygen atoms in addition to the nitrogen atom. That is, R 21 and R 22 The group represented by may be a group containing carbon atoms, hydrogen atoms, oxygen atoms, sulfur atoms, etc., and may preferably be a group containing only carbon atoms, hydrogen atoms, and oxygen atoms. 21 and R 22 Examples of compounds represented by formula (2) which are bonded to each other to form a ring include N-(meth)acryloyl oxazoline, N-acryloylthiooxazoline, N-acryloylthiazoline, N-acryloyl imidazoline, N-(meth)acryloyl piperazine, N-vinyl pyrrolidone and N-vinyl caprolactam.

[0102] From the viewpoint of better heat resistance of the cured product, the content of the compound represented by formula (2) is preferably 0.1 mass % or more, 0.2 mass % or more, 0.3 mass % or more, or 0.5 mass % or more, based on the total amount of the composition, and can be, for example, 2 mass % or less, 1.5 mass % or less, 1.3 mass % or less, or 1 mass % or less.

[0103] From the viewpoint of better heat resistance of the cured product, the content of the compound represented by formula (2) is preferably 1 part by mass or more, 2 parts by mass or more, 5 parts by mass or more, 8 parts by mass or more, or 9 parts by mass or more, and may be, for example, 30 parts by mass or less, 25 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, or 12 parts by mass or less, relative to 100 parts by mass of the total content of the polymerizable components.

[0104] The composition may further contain a compound represented by the following formula (3).

[0105]

[0106] [In formula (3), R 31 and R 32 Each independently represents a hydrogen atom or a methyl group, R 33 It represents a divalent group having a poly(meth)acrylate chain.]

[0107] In one embodiment, R 31 and R 32 One of them may be a hydrogen atom and the other may be a methyl group. In another embodiment, R 31 and R 32 Both of them can be hydrogen atoms. In another embodiment, R 31 and R 32 Both of these may be methyl groups.

[0108] The poly(meth)acrylate chain includes a structural unit represented by the following formula (3a).

[0109]

[0110] In formula (3a), R 34 represents a hydrogen atom or a monovalent organic group, R 35 represents a hydrogen atom or a methyl group.

[0111] By R 34 The monovalent organic group represented by may be, for example, a hydrocarbon group, or an organic group having an oxygen atom, a nitrogen atom, etc. The hydrocarbon group may be chain-shaped, or may have a ring (for example, an aromatic ring). The number of carbon atoms in the hydrocarbon group may be, for example, 1 or more, or 18 or less. Examples of the hydrocarbon group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, 2-propylheptyl, nonyl, decyl, isodecyl, dodecyl, octadecyl, phenyl, toluoyl, and benzyl.

[0112] As an organic group having an oxygen atom, for example, a group having an alkoxy group, a group having a hydroxyl group, a group having a carboxyl group, and a group having a glycidyl group can be cited. As examples of the group having an alkoxy group, 2-methoxyethyl and 3-methoxybutyl can be cited. As examples of the group having a hydroxyl group, 2-hydroxyethyl, 2-hydroxypropyl, and 4-hydroxybutyl can be cited. As an example of the group having a carboxyl group, a carboxyl group can be cited. As an example of the group having a glycidyl group, a glycidyl group can be cited. That is, as an organic group having an oxygen atom, for example, 2-methoxyethyl, 3-methoxybutyl, 2-hydroxyethyl, 2-hydroxypropyl, 4-hydroxybutyl, a carboxyl group, and a glycidyl group can be cited.

[0113] As an organic group having a nitrogen atom, for example, a group having an amino group or a nitrile group can be cited. As an example of a group having an amino group, a 2-aminoethyl group can be cited. As an example of a group having a nitrile group, a nitrile group can be cited. That is, as an organic group having a nitrogen atom, for example, a 2-aminoethyl group and a nitrile group can be cited.

[0114] In one embodiment, R 34The monovalent organic group represented by may be a group having a polar group, or may be a group having a hydroxyl group or a carboxyl group.

[0115] For example, the compound represented by formula (3) may be a compound represented by the following formula (3-2).

[0116]

[0117] In formula (3-2), R 31 and R 32 Respectively with R in formula (3) 31 and R 32 Same meaning, R 34 and R 35 Respectively with R in formula (3a) 34 and R 35 The meanings are the same, and a is an integer greater than 2.

[0118] The weight average molecular weight of the compound represented by formula (3) is preferably 3000 or more, 4000 or more, 5000 or more, 6000 or more, 7000 or more, 8000 or more, 9000 or more, 10000 or more, 11000 or more, 12000 or more, or 13000 or more. From the viewpoint of easy adjustment of the viscosity of the composition, the weight average molecular weight of the compound represented by formula (3) is preferably 100000 or less, 80000 or less, 60000 or less, 34000 or less, 31000 or less, or 28000 or less. a in formula (3a) may be an integer as long as the weight average molecular weight of the compound represented by formula (3) is within the above range.

[0119] The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the compound represented by formula (3) is preferably 1.4 or less or 1.2 or less.

[0120] The compound represented by formula (3) may be in liquid form at 23°C. In this case, from the viewpoint of facilitating application of the composition to the coating surface and improving the adhesion of the cured product to the coating surface, the viscosity of the compound represented by formula (3) at 23°C is 1000 Pa·s or less, 800 Pa·s or less, 700 Pa·s or less, 600 Pa·s or less, or 550 Pa·s or less. The viscosity of the compound represented by formula (3) at 25°C may be 5 Pa·s or more, 10 Pa·s or more, 15 Pa·s or more, 20 Pa·s or more, 25 Pa·s or more, 30 Pa·s or more, or 35 Pa·s or more.

[0121] The glass transition temperature (Tg) of the compound represented by formula (3) may be 0°C or lower, -10°C or lower, or -30°C or higher, or -60°C or higher, -50°C or higher, or -40°C or higher. The glass transition temperature is a value measured by differential scanning calorimetry.

[0122] From the viewpoint of better heat resistance of the cured product, the content of the compound represented by formula (3) is preferably 0.1 mass % or more, 0.3 mass % or more, or 0.4 mass % or more, based on the total amount of the composition, and can be, for example, 3 mass % or less, 2 mass % or less, or 1 mass % or less.

[0123] From the viewpoint of better heat resistance of the cured product, the content of the compound represented by formula (3) is preferably 1 part by mass or more, 3 parts by mass or more, 5 parts by mass or more, or 6 parts by mass or more, relative to a total of 100 parts by mass of the content of the polymerizable components. For example, it may be 40 parts by mass or less, 20 parts by mass or less, or 10 parts by mass or less.

[0124] For the purpose of adjusting the physical properties of the composition, the composition may further contain other polymerizable compounds copolymerizable with the compound represented by the formula (1), the compound represented by the formula (2), and the compound represented by the formula (3).

[0125] Other polymerizable compounds may be, for example, compounds having one (meth)acryloyl group other than the compound represented by formula (2). Such compounds may be, for example, alkyl (meth)acrylates. Other polymerizable compounds may be compounds having, in addition to one (meth)acryloyl group, an aromatic hydrocarbon group, a group containing a polyoxyalkylene chain, a group containing a heterocycle, an alkoxy group, a phenoxy group, a group containing a silyl group, a group containing a siloxane bond, a halogen atom, a hydroxyl group, a carboxyl group, an amino group or an epoxy group. In particular, by containing an alkyl (meth)acrylate in the composition, the viscosity of the composition can be easily adjusted. Furthermore, by containing a compound having, in addition to a (meth)acryloyl group, a hydroxyl group, a carboxyl group, an amino group or an epoxy group in the composition, the adhesion of the composition and its cured product to the component can be further improved.

[0126] The alkyl group (alkyl part other than the (meth)acryloyl group) in the alkyl (meth)acrylate may be linear, branched, or cyclic. The number of carbon atoms in the alkyl group may be, for example, 1 to 30. The number of carbon atoms in the alkyl group may be 1 to 11, 1 to 8, 1 to 6, or 1 to 4, or may be 12 to 30, 12 to 28, 12 to 24, 12 to 22, 12 to 18, or 12 to 14.

[0127] Examples of the alkyl (meth)acrylate having a linear alkyl group include alkyl (meth)acrylate having a linear alkyl group having 1 to 11 carbon atoms and alkyl (meth)acrylate having a linear alkyl group having 12 to 30 carbon atoms.

[0128] Examples of the (meth)acrylic acid alkyl ester having a linear alkyl group having 1 to 11 carbon atoms include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, and undecyl (meth)acrylate.

[0129] Examples of the alkyl (meth)acrylate having a linear alkyl group having 12 to 30 carbon atoms include dodecyl (meth)acrylate (lauryl (meth)acrylate), tetradecyl (meth)acrylate, hexadecyl (meth)acrylate (cetyl (meth)acrylate), octadecyl (meth)acrylate (stearyl (meth)acrylate), behenyl (meth)acrylate (behenyl (meth)acrylate), lignoceryl (meth)acrylate, hexadecyl (meth)acrylate, and dioctadecyl (meth)acrylate.

[0130] Examples of the alkyl (meth)acrylate having a branched alkyl group include alkyl (meth)acrylate having a branched alkyl group having 1 to 11 carbon atoms and alkyl (meth)acrylate having a branched alkyl group having 12 to 30 carbon atoms.

[0131] Examples of the alkyl (meth)acrylate having a branched alkyl group having 1 to 11 carbon atoms include sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, isobutyl (meth)acrylate, isoamyl (meth)acrylate, isopentyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, and isodecyl (meth)acrylate.

[0132] Examples of the alkyl (meth)acrylate having a branched alkyl group having 12 to 30 carbon atoms include isomyristyl (meth)acrylate, 2-propylheptyl (meth)acrylate, isoundecyl (meth)acrylate, isododecyl (meth)acrylate, isotridecyl (meth)acrylate, isopentadecyl (meth)acrylate, isohexadecyl (meth)acrylate, isoheptadecyl (meth)acrylate, isostearyl (meth)acrylate, and decyltetradecyl (meth)acrylate.

[0133] Examples of the alkyl (meth)acrylate having a cyclic alkyl group (cycloalkyl group) include cyclohexyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, terpene (meth)acrylate, and dicyclopentanyl (meth)acrylate.

[0134] Examples of the compound having a (meth)acryloyl group and an aromatic hydrocarbon group include benzyl (meth)acrylate and the like.

[0135] Examples of the compound having a (meth)acryloyl group and a group containing a polyoxyalkylene chain include polyethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, polybutylene glycol (meth)acrylate, and methoxypolybutylene glycol (meth)acrylate.

[0136] Examples of the compound having a (meth)acryloyl group and a group containing a heterocyclic ring include tetrahydrofurfuryl (meth)acrylate and the like.

[0137] Examples of the compound having a (meth)acryloyl group and an alkoxy group include 2-methoxyethyl acrylate and the like.

[0138] As a compound which has a (meth)acryloyl group and a phenoxy group, phenoxyethyl (meth)acrylate etc. are mentioned.

[0139] Examples of the compound having a (meth)acryloyl group and a group containing a silyl group include 3-acryloxypropyltriethoxysilane, 10-methacryloxydecyltrimethoxysilane, 10-acryloxydecyltrimethoxysilane, 10-methacryloxydecyltriethoxysilane, and 10-acryloxydecyltriethoxysilane.

[0140] As a compound which has a (meth)acryloyl group and a group containing a siloxane bond, silicone (meth)acrylate etc. are mentioned.

[0141] Examples of the compound having a (meth)acryloyl group and a halogen atom include (meth)acrylates having a fluorine atom. Examples of the (meth)acrylates having a fluorine atom include trifluoromethyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, 1,1,1,3,3,3-hexafluoro-2-propyl (meth)acrylate, perfluoroethyl methyl (meth)acrylate, perfluoropropyl (meth)acrylate, perfluorobutyl methyl (meth)acrylate, perfluoropentyl methyl (meth)acrylate, perfluorohexyl methyl (meth)acrylate, perfluoroheptyl methyl (meth)acrylate, perfluorooctyl methyl (meth)acrylate, perfluorononyl methyl (meth)acrylate, perfluorodecyl methyl (meth)acrylate, perfluoroundecyl methyl (meth)acrylate, perfluorododecyl methyl (meth)acrylate, and perfluorooctyl methyl (meth)acrylate. methyl (meth)acrylate, perfluorotridecyl methyl (meth)acrylate, perfluorotetradecyl methyl (meth)acrylate, 2-(trifluoromethyl)ethyl (meth)acrylate, 2-(perfluoroethyl)ethyl (meth)acrylate, 2-(perfluoropropyl)ethyl (meth)acrylate, 2-(perfluorobutyl)ethyl (meth)acrylate, 2-(perfluoropentyl)ethyl (meth)acrylate, 2-(perfluorohexyl)ethyl (meth)acrylate, 2-(perfluoroheptyl)ethyl (meth)acrylate, 2-(perfluorooctyl)ethyl (meth)acrylate, 2-(perfluorononyl)ethyl (meth)acrylate, 2-(perfluorotridecyl)ethyl (meth)acrylate, 2-(perfluorotetradecyl)ethyl (meth)acrylate, and the like.

[0142] Examples of the compound having a (meth)acryloyl group and a hydroxyl group include hydroxyalkyl (meth)acrylates and hydroxyalkylcycloalkane (meth)acrylates. Examples of the hydroxyalkyl (meth)acrylates include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, and 12-hydroxylauryl (meth)acrylate. Examples of the hydroxyalkylcycloalkane (meth)acrylates include (4-hydroxymethylcyclohexyl)methyl (meth)acrylate.

[0143] Examples of the compound having a (meth)acryloyl group and a carboxyl group include (meth)acrylic acid, hydroxyethyl (meth)acrylate, hydroxypentyl (meth)acrylate, monohydroxyethyl phthalate (e.g., "ARONIX M5400" manufactured by TOAGOSEI CO., LTD.), and 2-acryloyloxyethyl succinate (e.g., "NK Ester A-SA" manufactured by Shin-Nakamura Chemical Co., Ltd.).

[0144] Examples of the compound having a (meth)acryloyl group and an amino group include N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, and N,N-diethylaminopropyl (meth)acrylate.

[0145] Examples of the compound having a (meth)acryloyl group and an epoxy group include glycidyl (meth)acrylate, α-ethyl glycidyl (meth)acrylate, α-n-propyl glycidyl (meth)acrylate, α-n-butyl glycidyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, 4,5-epoxypentyl (meth)acrylate, 6,7-epoxyheptyl (meth)acrylate, α-ethyl (meth)acrylate-6,7-epoxyheptyl, 3-methyl-3,4-epoxybutyl (meth)acrylate, 4-methyl-4,5-epoxypentyl (meth)acrylate, 5-methyl-5,6-epoxyhexyl (meth)acrylate, β-methylglycidyl (meth)acrylate, and α-ethyl (meth)acrylate-β-methylglycidyl.

[0146] From the viewpoint of easily adjusting the viscosity of the composition or further improving the adhesion of the composition, the content of other polymerizable compounds is preferably 1% by mass or more, 2% by mass or more, 3% by mass or more, or 3.5% by mass or more, based on the total amount of the composition, and for example, may be 10% by mass or less, 8% by mass or less, 6% by mass or less, or 5% by mass or less.

[0147] From the viewpoint of easily adjusting the viscosity of the composition or further improving the adhesion of the composition, the content of other polymerizable compounds is preferably 30 parts by mass or more, 40 parts by mass or more, 50 parts by mass or more, 55 parts by mass or more, or 60 parts by mass or more, and for example, may be 90 parts by mass or less, 80 parts by mass or less, 70 parts by mass or less, or 65 parts by mass or less, relative to a total of 100 parts by mass of the content of the polymerizable components.

[0148] The composition may further contain a polymerization initiator. The polymerization initiator may be, for example, a thermal polymerization initiator that generates free radicals by heat, a photopolymerization initiator that generates free radicals by light, etc. The polymerization initiator is preferably a thermal polymerization initiator.

[0149] When the composition contains a thermal polymerization initiator, a cured product of the composition can be obtained by applying heat to the composition. In this case, the composition can be a composition that is cured by heating preferably at 105°C or higher, more preferably at 110°C or higher, and further preferably at 115°C or higher, for example, a composition that is cured by heating at 200°C or lower, 190°C or lower, or 180°C or lower. The heating time when the composition is heated can be appropriately selected according to the composition composition so that the composition is suitably cured.

[0150] As the thermal polymerization initiator, there can be mentioned azo compounds, organic peroxides, etc. As the azo compound, there can be mentioned azobisisobutyronitrile, azobis-4-methoxy-2,4-dimethylvaleronitrile, azobiscyclohexane-1-carbonitrile, azobisbenzoyl, etc. As the organic peroxide, there can be mentioned benzoyl peroxide, lauroyl peroxide, di-tert-butyl peroxide, di-tert-hexyl peroxide, di-tert-butyl peroxyhexahydroterephthalate, tert-butyl peroxy-2-ethylhexanoate, 1,1-tert-butylperoxy-3,3,5-trimethylcyclohexane, tert-butylperoxyisopropyl carbonate, etc. As for the thermal polymerization initiator, they can be used alone or in combination of two or more.

[0151] When the composition contains a photopolymerization initiator, for example, a cured product of the composition can be obtained by irradiating the composition with light (for example, light having at least a partial wavelength of 200 to 400 nm (ultraviolet light)). The light irradiation conditions can be appropriately set depending on the type of the photopolymerization initiator.

[0152] The photopolymerization initiator may be, for example, a benzoin ether-based photopolymerization initiator, an acetophenone-based photopolymerization initiator, an α-ketol-based photopolymerization initiator, an aromatic sulfonyl chloride-based photopolymerization initiator, a photoactive oxime-based photopolymerization initiator, a benzoin-based photopolymerization initiator, a benzyl-based photopolymerization initiator, a benzophenone-based photopolymerization initiator, a ketal-based photopolymerization initiator, a thioxanthone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, and the like.

[0153] Examples of the benzoin ether-based photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenylethane-1-one (for example, "Irgacure 651" manufactured by BASF), and anisole methyl ether. Examples of the acetophenone-based photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone (e.g., “Irgacure 184” manufactured by BASF), 4-phenoxydichloroacetophenone, 4-tert-butyl-dichloroacetophenone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one (e.g., “Irgacure 2959” manufactured by BASF), 2-hydroxy-2-methyl-1-phenyl-propane-1-one (e.g., “Irgacure 1173” manufactured by BASF), and methoxyacetophenone.

[0154] Examples of α-ketol-based photopolymerization initiators include 2-methyl-2-hydroxypropiophenone and 1-[4-(2-hydroxyethyl)-phenyl]-2-hydroxy-2-methylpropane-1-one. Examples of aromatic sulfonyl chloride-based photopolymerization initiators include 2-naphthalenesulfonyl chloride. Examples of photoactive oxime-based photopolymerization initiators include 1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-oxime.

[0155] Examples of benzoin-based photopolymerization initiators include benzoin. Examples of benzyl-based photopolymerization initiators include benzyl. Examples of benzophenone-based photopolymerization initiators include benzophenone, benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, α-hydroxycyclohexylphenylketone, and the like. Examples of ketal-based photopolymerization initiators include benzyl dimethyl ketal, and the like. Examples of thioxanthone-based photopolymerization initiators include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, and dodecylthioxanthone.

[0156] Examples of the acylphosphine oxide-based photopolymerization initiator include bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)(2,4,4-trimethylpentyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-n-butylphosphine oxide, bis(2,6-dimethoxybenzoyl)-(2-methylpropane-1-yl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-(1-methylpropane-1-yl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-tert-butylphosphine oxide, bis(2,6-dimethoxybenzoyl)cyclohexylphosphine oxide, bis(2,6-dimethoxybenzoyl)octylphosphine oxide, bis(2-methoxybenzoyl)(2,4,4-trimethylpentyl)phosphine oxide, bis(2-methoxybenzoyl)(1-methylpropane-1-yl)phosphine oxide, bis(2-methoxybenzoyl)(1-methylpropane-1-yl)phosphine oxide, bis(2,6-diethoxybenzoyl)(2-methylpropane-1-yl)phosphine oxide, bis(2,6-diethoxybenzoyl)(1-methylpropane-1-yl)phosphine oxide, bis(2,6-dibutoxybenzoyl)(2-methylpropane-1-yl)phosphine oxide, bis(2,4-dimethoxybenzoyl)(2-methylpropane-1-yl)phosphine oxide, bis(2,4,6-trimethylbenzoyl)(2,4-dipentyloxyphenyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)benzylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2- Phenylpropylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2-phenylethylphosphine oxide, 2,6-dimethoxybenzoylbenzylbutylphosphine oxide, 2,6-dimethoxybenzoylbenzyloctylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,5-diisopropylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2-methylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-4-methylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,5-diethylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,3,5,6-tetramethylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,3,5,6-tetramethylphenylphosphine oxide, 2,4,6-trimethylbenzoyl)-2,4-di-n-butoxyphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)isobutylphosphine oxide, 2,6-dimethoxybenzoyl-2,4,6-trimethylbenzoyl-n-butylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,4-dibutoxyphenylphosphine oxide, 1,10-bis[bis(2,4,6-trimethylbenzoyl)phosphine oxide]decane, tri(2-methylbenzoyl)phosphine oxide, and the like.

[0157] The above-mentioned photopolymerization initiators can be used alone or in combination of two or more.

[0158] From the viewpoint of suitably performing polymerization, the content of the polymerization initiator is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, further preferably 0.1 parts by mass or more, and particularly preferably 0.5 parts by mass or more, relative to a total of 100 parts by mass of the content of the polymerizable components. From the viewpoint of keeping the molecular weight of the polymer in the cured product of the composition within a suitable range and suppressing decomposition products, the content of the polymerization initiator is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and further preferably 3 parts by mass or less, relative to a total of 100 parts by mass of the content of the polymerizable components.

[0159] The composition may further contain a thermally conductive filler. In this case, the thermal conductivity of the composition and its cured product is improved, so the composition can be suitably used as a thermally conductive material, a heat dissipation material, etc. A thermally conductive filler refers to a filler having a thermal conductivity of 10 W / m·K or more.

[0160] The thermally conductive filler may be insulating or conductive. The thermally conductive filler is preferably an insulating filler. Materials constituting the insulating thermally conductive filler include aluminum oxide, aluminum hydroxide, magnesium oxide, beryllium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, silicon dioxide, aluminum fluoride, calcium fluoride, zinc oxide, and the like. Materials constituting the conductive thermally conductive filler include aluminum, silver, copper, and the like. The shape of the thermally conductive filler may be spherical or polyhedral.

[0161] From the viewpoint of being able to configure the cured product of the composition to be thinner, the average particle size of the thermally conductive filler is preferably 50 μm or less, more preferably 40 μm or less, and further preferably 30 μm or less, and may be 0.05 μm or more, 0.1 μm or more, or 0.3 μm or more. The average particle size of the thermally conductive filler refers to the particle size (D50) at which the volume cumulative particle size distribution becomes 50%, and is measured using a laser diffraction particle size distribution measuring device (e.g., SALD-2300 (manufactured by SHIMADZU CORPORATION).

[0162] From the viewpoint of improving the thermal conductivity of the composition, the content of the thermally conductive filler is preferably 60% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, based on the total amount of the composition, and may be 97% by mass or less, 95% by mass or less, or 93% by mass or less.

[0163] From the viewpoint of improving the thermal conductivity of the composition, the content of the thermally conductive filler is preferably 65 volume % or more, more preferably 70 volume % or more, further preferably 75 volume % or more, based on the total volume of the composition, and can be 90 volume % or less, 88 volume % or less, or 85 volume % or less.

[0164] The composition may further contain a coupling agent. The coupling agent may be, for example, a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, etc. The coupling agent is preferably a silane coupling agent.

[0165] The silane coupling agent may be a compound having an alkoxysilyl group such as a dialkoxysilyl group or a trialkoxysilyl group. The silane coupling agent may have, for example, an organic functional group, an alkyl group having 1 to 10 carbon atoms, etc. As the organic functional group, vinyl, (meth)acryloyl, epoxy, amino, mercapto, imidazole, etc. may be mentioned. The silane coupling agent preferably has a (meth)acryloyl group. The above-mentioned coupling agents may be used alone or in combination of two or more.

[0166] From the viewpoint of reducing the viscosity of the composition and further improving the fracture strength of the cured product, the content of the coupling agent is preferably 0.01 parts by mass or more, 0.02 parts by mass or more, or 0.025 parts by mass or more relative to 100 parts by mass of the thermally conductive filler. In addition, the content of the coupling agent is preferably 2 parts by mass or less, 1.5 parts by mass or less, or 1 part by mass or less relative to 100 parts by mass of the thermally conductive filler. This is because: if the content of the coupling agent is too much, the coupling agent is prone to self-condensation, and as a result, it may cause an excessive increase in the fracture strength of the cured product, an increase in the tensile elastic modulus, and an excessive decrease in the elongation at break.

[0167] When the composition contains a coupling agent, the coupling agent is preferably chemically adsorbed on the surface of the thermally conductive filler. In this case, the viscosity of the composition decreases, and the fracture strength of the cured product of the composition becomes higher. All of the coupling agent contained in the composition may be chemically adsorbed on the surface of the thermally conductive filler, or a part of the coupling agent may be chemically adsorbed on the surface of the thermally conductive filler.

[0168] It is possible to confirm that the coupling agent is chemically adsorbed on the surface of the thermally conductive filler by IR measurement (diffuse reflectance method) of the thermally conductive filler. Specifically, first, a solvent (e.g., methyl ethyl ketone) is added to the composition, and after dissolving the components other than the thermally conductive filler such as the polymerizable component, the thermally conductive filler is recovered by filtration and vacuum dried. At this time, drying is performed at a temperature of less than 100°C to prevent the unreacted coupling agent that is not chemically adsorbed on the surface of the thermally conductive filler from reacting. Next, the dried thermally conductive filler is added to an excess of methyl ethyl ketone (40 times or more of the mass of the thermally conductive filler contained in the composition) and stirred, and allowed to stand at room temperature (20 to 30°C) for more than 12 hours, and after the thermally conductive filler is precipitated, the supernatant (more than 90% by mass of the added methyl ethyl ketone) is removed. Thus, it is believed that the coupling agent that is not chemically adsorbed on the surface of the thermally conductive filler is removed. Then, after the thermally conductive filler is dried in an oven at 100°C, the IR measurement (diffuse reflectance method) of the thermally conductive filler is performed. In the case where the coupling agent is chemically adsorbed on the surface of the thermally conductive filler, the -1 A peak derived from a methoxy group, a methyl group or a methylene chain of the coupling agent was observed in the range of .

[0169] As a method for chemically adsorbing the coupling agent on the surface of the thermally conductive filler, for example, the following method can be cited: first, a liquid for hydrolyzing the coupling agent (hydrolysis treatment liquid) is prepared, the hydrolysis treatment liquid is added to the thermally conductive filler, and after stirring, the thermally conductive filler is dried, crushed as needed, and classified.

[0170] The composition may further contain an adhesive. Examples of adhesives include rosin-based resins and terpene resins. The content of the adhesive may be 0.1 parts by mass or more, 1 part by mass or more, or 3 parts by mass or more, or 20 parts by mass or less, 15 parts by mass or less, 12 parts by mass or less, or 10 parts by mass or less relative to a total of 100 parts by mass of the content of the polymerizable component.

[0171] From the viewpoint of improving the thermal reliability of the cured product of the composition, the composition may further contain an antioxidant. The antioxidant may be, for example, a phenolic antioxidant, a benzophenone antioxidant, a benzoate antioxidant, a hindered amine antioxidant, a benzotriazole antioxidant, etc., preferably a phenolic antioxidant.

[0172] The phenolic antioxidant has, for example, a hindered phenol structure (hindered phenol ring). The hindered phenol structure (hindered phenol ring) may be, for example, a structure in which a tert-butyl group is bonded to one or both of the ortho positions of the hydroxyl group in the phenolic ring. The phenolic antioxidant has, for example, one or more such hindered phenol rings, preferably two or more, more preferably three or more, and even more preferably four or more.

[0173] The content of the antioxidant may be 0.1 mass % or more, 0.2 mass % or more, or 0.3 mass % or less, or 10 mass % or less, 9 mass % or less, 8 mass % or less, or 7 mass % or less, based on the total amount of the composition.

[0174] The composition may further contain other additives as required. As other additives, for example, surface treatment agents (except coupling agents), dispersants, curing accelerators, colorants, crystal nucleating agents, thermal stabilizers, foaming agents, flame retardants, damping agents, dehydrating agents, flame retardant aids (such as metal oxides), etc. may be cited. Based on the total amount of the composition, the content of other additives may be 0.1% by mass or more, or 30% by mass or less.

[0175] The composition is preferably in a liquid state at 25° C. Thus, it can be appropriately applied to the surface of an object such as a component that becomes a heat source, a cooling component, etc., and the adhesion to the applied surface can also be improved. The composition may be in a solid state at 25° C. In this case, it is preferred to make the composition liquid by heating (for example, at a temperature of 50° C. or above).

[0176] [Combination group]

[0177] The above-mentioned composition can be in the state of a plurality of liquid compositions (composition groups). The composition group of one embodiment is a composition group having a first liquid containing an oxidizing agent and a second liquid containing a reducing agent. At least one of the first liquid and the second liquid contains the above-mentioned compound represented by formula (1). Furthermore, at least one of the first liquid and the second liquid contains the above-mentioned acrylic copolymer. By mixing the first liquid and the second liquid, the oxidizing agent and the reducing agent react to generate free radicals, and polymerization of polymerizable components such as the compound represented by formula (1) is carried out. According to the composition group of this embodiment, by mixing the first liquid and the second liquid, a solidified product of the mixture of the first liquid and the second liquid can be immediately obtained. That is, according to the composition group, a solidified product of the composition can be quickly obtained.

[0178] In the composition set, it is preferred that the first liquid contains an oxidizing agent, a compound represented by formula (1) and an acrylic copolymer, and the second liquid contains a reducing agent, a compound represented by formula (1) and an acrylic copolymer.

[0179] The content of the compound represented by formula (1) based on the total amount of liquids constituting the composition set (for example, the total amount of the first liquid and the second liquid in the case of a two-liquid composition set) can be the same as the content of the compound represented by formula (1) based on the total amount of the above-mentioned composition. The same also applies to the content of the acrylic copolymer contained in the composition set.

[0180] The oxidant contained in the first liquid has a role as a polymerization initiator (free radical polymerization initiator). The oxidant can be, for example, an organic peroxide or an azo compound. The organic peroxide can be, for example, a hydroperoxide, a peroxydicarbonate, a peroxyester, a peroxyketal, a dialkyl peroxide, a diacyl peroxide, etc. The azo compound can be AIBN (2, 2'-azobisisobutyronitrile), V-65 (azobisdimethylvaleronitrile), etc. The oxidant can be used alone or in combination of two or more.

[0181] Examples of the hydroperoxide include diisopropylbenzene hydroperoxide and cumene hydroperoxide.

[0182] Examples of the peroxydicarbonate include di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis(4-tert-butylcyclohexyl)peroxydicarbonate, di-2-ethoxymethoxyperoxydicarbonate, di(2-ethylhexylperoxy)dicarbonate, dimethoxybutylperoxydicarbonate, and di(3-methyl-3-methoxybutylperoxy)dicarbonate.

[0183] Examples of the peroxyesters include cumyl peroxyneodecanoate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, 1-cyclohexyl-1-methylethyl peroxyneodecanoate, tert-hexyl peroxyneodecanoate, tert-butyl peroxytrimethylacetate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane ... tert-Butyl peroxy-2-ethylhexanoate, tert-Hexyl peroxy-2-ethylhexanoate, tert-Butyl peroxy-2-ethylhexanoate, tert-Butyl peroxyisobutyrate, 1,1-bis(tert-butylperoxy)cyclohexane, tert-Butyl peroxy-3,5,5-trimethylhexanoate, tert-Butyl peroxylaurate, 2,5-dimethyl-2,5-di(m-toluoylperoxy)hexane, tert-Hexyl peroxybenzoate, tert-Butyl peroxyacetate, etc.

[0184] Examples of the peroxyketal include 1,1-bis(tert-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-hexylperoxy)cyclohexane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-butylperoxy)cyclododecane, and 2,2-bis(tert-butylperoxy)decane.

[0185] Examples of the dialkyl peroxide include α,α′-bis(tert-butylperoxy)diisopropylbenzene, diisopropylphenyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, and tert-butylisopropylphenyl peroxide.

[0186] Examples of the diacyl peroxide include isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, succinic peroxide, benzoyl peroxytoluene, and benzoyl peroxide.

[0187] From the viewpoint of storage stability, the oxidizing agent is preferably a peroxide, more preferably a hydroperoxide, and still more preferably cumene hydroperoxide.

[0188] The content of the oxidant may be 0.1 mass % or more, 0.5 mass % or more, or 10 mass % or less, 5 mass % or less, or 3 mass % or less, based on the total amount of the liquid constituting the composition group.

[0189] The reducing agent contained in the second liquid may be, for example, a tertiary amine, a thiourea derivative, a transition metal salt, etc. As the tertiary amine, triethylamine, tripropylamine, tributylamine, N,N-dimethyl-p-toluidine, etc. may be mentioned. As the thiourea derivative, 2-mercaptobenzimidazole, methylthiourea, dibutylthiourea, tetramethylthiourea, ethylenethiourea, etc. may be mentioned. As the transition metal salt, cobalt naphthenate, copper naphthenate, vanadium acetylacetonate, etc. may be mentioned. The reducing agent may be used alone or in combination of two or more.

[0190] From the viewpoint of excellent curing speed, the reducing agent is preferably a thiourea derivative or a transition metal salt. For example, the thiourea derivative may be ethylenethiourea. From the same viewpoint, the transition metal salt is preferably vanadyl acetylacetonate.

[0191] The content of the reducing agent may be 0.05 mass % or more, 0.1 mass % or more, or 0.3 mass % or less, or 5 mass % or less, or 3 mass % or less, or 1 mass % or less, based on the total amount of the liquid constituting the composition group.

[0192] The composition group may also contain an ester thixotropic agent that can be used in the above-mentioned composition, a compound represented by formula (2), a compound represented by formula (3), other polymerizable compounds and additives. Examples of additives that can be used in the above-mentioned composition include coupling agents, adhesives, antioxidants and other additives. In addition, the composition group may also contain a thermally conductive filler that can be used in the above-mentioned composition, and a coupling agent may be chemically adsorbed on the surface of the thermally conductive filler. Their components may be contained in one or both of the first liquid and the second liquid, or in a third liquid different from the first liquid and the second liquid. The content of their components based on the total amount of the liquid constituting the composition group may be the same as the range of the content of their components based on the total amount of the above-mentioned composition.

[0193] The cured product of the above-mentioned composition and composition group has thermal conductivity and excellent fracture strength, and is therefore suitable for thermally conductive materials (also referred to as heat dissipation materials), pressure-sensitive adhesives, grain adhesives, structural adhesives, battery adhesives, stress relaxants, sealants, coatings, coatings and other uses. Similarly, the cured product of the above-mentioned composition and the mixture of the composition group have excellent fracture strength, and are therefore suitable for each of the above-mentioned uses. In the case where the composition and composition group contain a thermally conductive filler, the composition, the composition group and their cured products can be suitably used as thermally conductive materials (also referred to as heat dissipation materials). Furthermore, in the case where a coupling agent is chemically adsorbed on the surface of the thermally conductive filler, the viscosity of the composition and the composition group is low, and their cured products have higher fracture strength, and are therefore particularly suitable for the above-mentioned uses.

[0194] [thing]

[0195] Next, an article having a cured product (hereinafter, also referred to as a "cured product") of the above-mentioned composition or composition group is described. An article of one embodiment has a heat source and a cured product in thermal contact with the heat source. Hereinafter, as a more specific example of the article, an electronic component is described as an example. Figure 1 This is a schematic cross-sectional view showing one embodiment of an electronic component including a cured product. Figure 1 The electronic component 1A shown includes a semiconductor wafer 21 as a heat source and a heat sink 22 as a heat dissipation unit.

[0196] The electronic component 1A includes a cured product 11 provided between a semiconductor wafer 21 and a heat sink 22. The cured product 11 is a cured product of the above-mentioned composition or a cured product of a mixture of the composition group.

[0197] Since the cured product 11 has thermal conductivity, the cured product 11 functions as a thermally conductive material (thermal interface material) in the electronic component 1A, and heat is conducted from the semiconductor wafer 21 to the heat sink 22. The heat is then dissipated from the heat sink 22 to the outside.

[0198] Since the cured product 11 has excellent heat resistance, it is possible to suppress thermal degradation of the cured product 11. Therefore, the heat generated from the semiconductor wafer 21 can be efficiently conducted to the heat sink 22.

[0199] The cured product 11 can also be obtained by placing a liquid composition (or composition group) between the semiconductor wafer 21 and the heat sink 22 and then curing it. Therefore, the generation of voids due to dripping and overflowing can be suppressed, and as a result, the cured product 11 can have excellent adhesion (adhesion to the surfaces of the semiconductor wafer 21 and the heat sink 22). In addition, the curing method and curing conditions of the composition can be adjusted according to the composition of the composition or the type of polymerization initiator.

[0200] exist Figure 1 In the electronic component 1A described in the figure, the cured product 11 is arranged to be in direct contact with the semiconductor chip 21 and the heat sink 22, but the cured product 11 only needs to be in thermal contact with the heat source. In another embodiment, the cured product 11 can be arranged to be in contact with the heat source (for example, the semiconductor chip) via other components.

[0201] Figure 2 This is a schematic cross-sectional view showing another embodiment of an electronic component including a cured product. Figure 2 The electronic component 1B shown is a processor including a semiconductor chip 21 as a heat source disposed on one side of a substrate 23 via a primer 24, a heat sink 22 as a heat dissipation portion, and a heat sink 25 disposed between the semiconductor chip 21 and the heat sink 22. A first cured product 11 is disposed between the semiconductor chip 21 and the heat sink 25 so as to be in contact with the semiconductor chip 21. A second cured product 11 is disposed between the heat sink 25 and the heat sink 22.

[0202] The substrate 23, the primer 24, and the heat sink 25 can be formed of materials commonly used in the technical field. For example, the substrate 23 can be a laminate substrate, the primer 24 can be formed of a resin such as epoxy resin, and the heat sink 25 can be a metal plate.

[0203] The first cured product 11 and the second cured product 11 are cured products of the above-mentioned curable composition or cured products of a mixture of the above-mentioned curable composition group. The first cured product 11 is in direct contact with the semiconductor wafer 21 as a heat source, but the second cured product 11 is in thermal contact with the semiconductor wafer 21 as a heat source via the first cured product 11 and the heat sink 25.

[0204] The first cured product 11 and the second cured product 11 have thermal conductivity, and therefore function as thermally conductive materials (thermal interface materials) in the electronic component 1B. That is, the first cured product 11 promotes heat conduction from the semiconductor chip 21 to the heat sink 25. In addition, the second cured product 11 promotes heat conduction from the heat sink 25 to the heat sink 22. Then, the heat is dissipated from the heat sink 22 to the outside.

[0205] The first cured product 11 and the second cured product 11 also have excellent heat resistance, so the first cured product 11 and the second cured product 11 can suppress thermal degradation. Therefore, the heat generated from the semiconductor wafer 21 can be more effectively conducted to the heat sink 25, and further, the heat can be more effectively conducted to the heat sink 22.

[0206] The first cured product 11 and the second cured product 11 can also be obtained by placing a liquid composition (composition group) between the semiconductor chip 21 and the heat sink 25, or between the heat sink 25 and the heat sink 22, and then curing. Therefore, in the electronic component 1B, it is possible to suppress the generation of voids due to dripping and overflowing of the composition (composition group), and as a result, the first cured product 11 and the second cured product 11 can have excellent adhesion (adhesion to the surface of the semiconductor chip 21, the heat sink 25 and / or the heat sink 22).

[0207] Example

[0208] Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[0209] In the examples and comparative examples, the following components were used.

[0210] (A) A compound represented by the following formula (1-5) synthesized by the following steps (weight average molecular weight: 16000, a mixture of integers of approximately 246±5 and approximately 105±5 in formula (1-5), viscosity at 25°C: 55 Pa·s)

[0211]

[0212] In the formula (1-5), -r- is a symbol indicating random copolymerization.

[0213] (B) N-acryloyl methyl methacrylate ("ACMO" manufactured by KJ Chemicals Corporation) represented by the following formula (2-2)

[0214]

[0215] (C) A compound represented by the following formula (3-3) ("RC200C" manufactured by KANEKA CORPORATION, weight average molecular weight: 18,000, R in formula (3-3) 31 and R 32 is a hydrogen atom or a methyl group and R 34 A compound having a polar group, viscosity at 23°C: 530 Pa·s, Tg: -39°C)

[0216]

[0217] (D-1) 2-Ethylhexyl acrylate ("AEH" manufactured by NIPPON SHOKUBAI CO., LTD.)

[0218] (D-2) Isodecyl acrylate ("FA111A" manufactured by Showa Denko Materials Co., Ltd.)

[0219] (D-3) 4-Hydroxybutyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd.)

[0220] (D-4) 2-Acryloyloxyethyl succinate ("NK Ester A-SA" manufactured by Shin-Nakamura Co., Ltd.)

[0221] (E-1) A triblock copolymer in which a polymethyl methacrylate block, a poly-n-butyl acrylate block and a polymethyl methacrylate block are sequentially bonded ("KURARITY (registered trademark) LA2270 manufactured by KURARAY CO., LTD.," methyl methacrylate content based on the total amount of monomer units: 40% by mass, weight average molecular weight: about 50,000)

[0222] (E-2) a triblock copolymer in which a polymethyl methacrylate block, a poly-n-butyl acrylate block and a polymethyl methacrylate block are sequentially bonded ("KURARITY (registered trademark) LA2250 manufactured by KURARAY CO., LTD.," methyl methacrylate content based on the total amount of monomer units: 30% by mass, weight average molecular weight: about 46,000)

[0223] (e-1) a triblock copolymer in which a polymethyl methacrylate block, a poly-n-butyl acrylate block and a polymethyl methacrylate block are sequentially bonded ("KURARITY (registered trademark) LA2140 manufactured by KURARAY CO., LTD., content of methyl methacrylate based on the total amount of monomer units: 20% by mass, weight average molecular weight: about 47,000)

[0224] (F-1) Ester-based thixotropic agent ("DISPARLON 3500" manufactured by Kusumoto Chemicals, Ltd., polyether phosphate ester)

[0225] (F-2) Ester-based thixotropic agent ("Flowon RCM100" manufactured by KYOEISHA CHEMICAL Co., LTD., main components: fatty acid ester and aromatic ester.)

[0226] (G) Adhesive ("Adhesive KE311" manufactured by Arakawa Chemical Industries, Ltd.)

[0227] (H) Phenol antioxidant ("Irganox 1010" manufactured by BASF Japan Ltd.)

[0228] (I-1) Alumina filler ("Advanced Alumina AA-18" manufactured by Sumitomo Chemical Co., Ltd.)

[0229] (I-2) Alumina filler ("Alumina Beads CB-A30S" manufactured by SHOWA DENKO KK)

[0230] (I-3) Alumina filler ("Advanced Alumina AA-3" manufactured by Sumitomo Chemical Co., Ltd.)

[0231] (I-4) Alumina filler ("Advanced Alumina AA-04" manufactured by Sumitomo Chemical Co., Ltd.)

[0232] (J-1) A silane coupling agent represented by the following formula (4-1) ("KBM-5803" manufactured by Shin-Etsu Chemical Co., Ltd.)

[0233]

[0234] (J-2) A silane coupling agent represented by the following formula (4-2) ("KBM3103C" manufactured by Shin-Etsu Chemical Co., Ltd.)

[0235]

[0236] [Synthesis of the compound represented by formula (1-5)]

[0237] A 500mL flask consisting of an agitator, a thermometer, a nitrogen inlet pipe, an outlet pipe and a heating jacket was used as a reactor. 240g of polyoxyethylene polyoxypropylene glycol (molecular weight 16,000) and 300g of toluene were added to the reactor, the mixture was stirred at a stirring speed of 250 times / min at 45°C, nitrogen was introduced at a rate of 100mL / min, and the mixture was stirred for 30 minutes. Then, the temperature was lowered to 25°C. After the cooling was completed, 2.9g of chlorinated acryloyl was added dropwise to the reactor and stirred for 30 minutes. Then, 3.8g of triethylamine was added dropwise and stirred for 2 hours. Then, the temperature was raised to 45°C and reacted for 2 hours. The reaction solution was filtered, the filtrate was desolvated, and a compound represented by formula (1-5) was obtained.

[0238] [Preparation of Composition]

[0239] The components were mixed in the mixing ratio shown in Table 1 to obtain the compositions of the embodiments and comparative examples. In addition, the mixed filler in Table 1 is obtained by mixing the above-mentioned thermally conductive fillers (I-1) to (I-4) in a mass ratio of (I-1): (I-2): (I-3): (I-4) = 33:33:24:10. The mixed filler was surface treated with coupling agents (J-1) and (J-2) before mixing with other components. In the surface treatment, 0.025 parts by mass of coupling agent (J-1) and 0.025 parts by mass of coupling agent (J-2) were used for 100 parts by mass of the mixed filler. The specific method of the surface treatment is as follows.

[0240] The mixed filler was placed in a 10L planetary mixer (the inner wall and the stirring blades were made of stainless steel) and stirred at a speed of 200-500 rpm for 10 minutes. Then, the hydrolysis treatment solution of the coupling agent prepared by the method described below was placed and stirred at a speed of 200-500 rpm for 10 minutes. Then, it was transferred to a barrel, dried in an oven at 120°C for 8 hours, crushed as needed, and classified to obtain a thermally conductive filler after surface treatment.

[0241] The method for preparing the hydrolysis treatment liquid of the coupling agent is as follows. In a beaker, 0.1 mol / L of acetic acid aqueous solution, methanol and coupling agent (J-1) are prepared in a mixing ratio of 38% by mass of acetic acid aqueous solution, 56% by mass of methanol and 6% by mass of coupling agent, and stirred and mixed at 50°C for 1 hour. After the obtained mixed solution is cooled, methanol and coupling agent (J-2) are further prepared, and stirred and mixed at 25°C for 10 minutes to prepare a hydrolysis treatment liquid. The hydrolysis treatment liquid of the coupling agent is added to the mixed filler within 30 minutes after preparation.

[0242] The ratio of the volume of the surface-treated mixed filler to the total volume of other components (total volume of other components: volume of the mixed filler) was 25:75.

[0243] When (e-1) was used instead of (E-1) or (E-2), turbidity occurred during the preparation of the composition, and the preparation of the composition and the preparation and evaluation of the cured product described below could not be performed.

[0244] [Production of Cured Material]

[0245] The composition of each example was filled in a 10 cm×10 cm×0.2 mm template (SUS plate), covered with a SUS plate, and then heated at 135° C. for 15 minutes for curing to obtain a cured product with a thickness of 0.2 mm.

[0246] [Measurement of breaking strength, breaking elongation and tensile elastic modulus]

[0247] The elongation at break, tensile modulus, and breaking strength of the cured product at 25° C. were measured using a tensile tester ("Autograph EZ-TEST EZ-S" manufactured by SHIMADZU CORPORATION). The measurement was performed in accordance with JIS K7161 for a cured product having a shape of 0.2 mm (thickness) × 5 mm (width) × 30 mm (length) under the conditions of a chuck distance of 20 mm and a tensile speed of 5 mm / min.

[0248] [Measurement of thermal conductivity]

[0249] The cured product was cut into a square of 10 mm × 10 mm × 0.2 mm, blackened by graphite spraying, and then the thermal diffusivity at 25° C. was measured by a xenon flash method (“LFA447nanoflash” manufactured by NETZSCH-Geratebau GmbH, Selb / Bayern). The thermal conductivity in the thickness direction of the cured product was calculated based on the following formula, based on the product of this value, the density measured by the Archimedean method, and the specific heat at 25° C. measured by a differential scanning calorimeter (“DSC250” manufactured by TA Instruments Japan Inc.).

[0250] Thermal conductivity λ(W / (m·K))=α×ρ×Cp

[0251] α: Thermal diffusivity (m 2 / s)

[0252] ρ: Density (kg / cm 3 )

[0253] Cp: ​​Specific heat (capacity) (kJ / (kg·K))

[0254] [Evaluation of heat resistance]

[0255] The cured product was cut into 3 cm x 3 cm pieces, and after measuring the weight (initial weight), it was placed in a 150°C thermostatic bath, taken out after 1000 hours or 1500 hours, and the weight was measured again (weight after 1000 hours or weight after 1500 hours). The weight loss was calculated by the following formula.

[0256] Weight loss after 1000 hours (%) = (weight after 1000 hours / initial weight) × 100

[0257] Weight loss after 1500 hours (%) = (weight after 1500 hours / initial weight) × 100

[0258] Table 1 shows the results of measuring various physical properties of the compositions of Examples and Comparative Examples and their cured products.

[0259] [Table 1]

[0260]

[0261] Explanation of symbols

[0262] 1A, 1B-electronic parts, 11-cured product of the composition, 21-semiconductor chip (heat source), 22-heat sink, 23-substrate, 24-primer, 25-heat sink.

Claims

1. A composition comprising: A compound represented by the following formula (1); and A copolymer comprising, as monomer units, methyl (meth)acrylate and an alkyl (meth)acrylate having an alkyl group having 2 to 12 carbon atoms, In formula (1), R 11 and R 12 Each independently represents a hydrogen atom or a methyl group, R 13 represents a divalent group having a polyoxyalkylene chain, In the composition, The content of the methyl (meth)acrylate is 25% by mass or more based on the total amount of monomer units contained in the copolymer.

2. The composition according to claim 1, further comprising a thermally conductive filler.

3. The composition according to claim 1 or 2, further comprising a compound represented by the following formula (2): In formula (2), R 21 and R 22 Each independently represents a hydrogen atom or a monovalent organic group, and may be bonded to each other to form a ring, R 23 represents a hydrogen atom or a methyl group.

4. The composition according to claim 1 or 2, further comprising a compound represented by the following formula (3): In formula (3), R 31 and R 32 Each independently represents a hydrogen atom or a methyl group, R 33 It represents a divalent group having a poly(meth)acrylate chain.

5. A cured product, which is a cured product of the composition according to claim 1 or 2.

6. An article having: heat source; and The cured product according to claim 5 in thermal contact with the heat source.

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