Resin compositions, varnishes, prepregs, cured products, films, laminates, metal-clad laminates, and printed circuit boards.

Abstract

To provide a resin composition and a varnish which are capable of giving a prepreg, a film, a laminate, a metal-clad laminate, a printed wiring board and an electronic device improved in performance balance between low dielectric characteristics and low thermal expansion, and to provide a prepreg, a film, a laminate, a metal-clad laminate, a printed wiring board and an electronic device improved in performance balance between low dielectric characteristics and low thermal expansion.SOLUTION: The resin composition contains: a thermosetting cyclic olefinic copolymer (A) having a functional group (α) usable for a crosslinking reaction; a radical polymerization initiator (B); and a crosslinking agent (C) having a benzocyclobutene structure. The content of a peroxide-based polymerization initiator is less than 50 pts.mass based on 100 pts.mass of the radical polymerization initiator (B).SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resin composition, varnish, prepreg, cured product, film, laminate, metal-clad laminate, printed wiring board, and electronic device.

Background Art

[0002] In recent years, in addition to the increase in wireless communication devices using high-frequency bands, with the increase in communication speed, inevitably, higher-frequency bands are often used. Along with this, in order to reduce transmission loss at high frequencies to the limit, a circuit board with a small dielectric loss tangent (that is, low dielectric characteristics) is required. On the other hand, in recent years, such wireless communication devices and the like have been further miniaturized and enhanced in performance. Therefore, dimensional stability (especially dimensional stability against heat) is required for the laminate for printed wiring boards and its materials. This requirement is remarkable in the area of semiconductor package substrates.

[0003] Patent Document 1 aims to provide a thermosetting resin composition that is halogen-free, has flame retardancy while suppressing a decrease in heat resistance and deterioration of dielectric properties, and has excellent heat resistance, low thermal expansion, low relative permittivity, and low dielectric loss tangent, a prepreg, laminate, printed wiring board, and high-speed communication compatible module using the same. It contains (A) an addition reaction product of a maleimide compound (a1) having at least two N-substituted maleimide groups in one molecule and an amine compound (a2) having at least two primary amino groups in one molecule, (B) a thermoplastic elastomer, (C) a copolymer resin containing a structural unit derived from an aromatic vinyl compound and a structural unit derived from a carboxylic anhydride, and (D) a phosphorus-based flame retardant as a flame retardant. The structural unit derived from the aromatic vinyl compound of the component (C) is represented by the general formula (C-1), and the structural unit derived from the carboxylic anhydride is a structural unit derived from maleic anhydride represented by the general formula (C-2). As the component (C), R in the general formula (C-1) C1is a hydrogen atom, x is 0, and a thermosetting resin composition containing a copolymer resin in which the content ratio [(C-1) / (C-2)] (molar ratio) of the structural unit represented by the general formula (C-1) and the structural unit represented by the general formula (C-2) is 5 to 10 is described.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention provides a resin composition, varnish, cured product, prepreg, film, laminate, metal-clad laminate, printed wiring board, and electronic device capable of obtaining a prepreg, film, laminate, metal-clad laminate, printed wiring board, and electronic device with improved performance balance of low dielectric characteristics and low thermal expansion.

Means for Solving the Problems

[0006] The present inventors intensively studied to solve the above problems. As a result, in the resin composition, a thermosetting cyclic olefin copolymer having a functional group that can be used for a crosslinking reaction is used, and a radical polymerization initiator and a crosslinking agent having a benzocyclobutene structure are used, whereby the performance balance of low dielectric characteristics and low thermal expansion of the obtained prepreg, cured product, film, laminate, metal-clad laminate, printed wiring board, and electronic device can be improved, and the present invention was completed. According to the present invention, there are provided the following resin composition, varnish, prepreg, cured product, film, laminate, metal-clad laminate, printed wiring board, and electronic device.

[0007] The present invention is as follows.

[0008] [1] A thermosetting cyclic olefin copolymer (A) having a functional group (α) that can be used in a crosslinking reaction, a radical polymerization initiator (B), a crosslinking agent (C) having a benzocyclobutene structure, A resin composition containing a resin composition in which the content of the peroxide-based polymerization initiator is less than 50 parts by mass with respect to 100 parts by mass of the radical polymerization initiator (B). [2] The resin composition according to [1], wherein the content of the crosslinking agent (C) is 1 to 50 parts by mass with respect to 100 parts by mass of the copolymer (A). [3] The resin composition according to [1] or [2], wherein the total content of the copolymer (A), the radical polymerization initiator (B), and the crosslinking agent (C) in the resin composition is 50 to 100% by mass. [4] The resin composition according to any one of [1] to [3], wherein the crosslinking agent (C) has one or more functional groups (β) that can be used in a crosslinking reaction. [5] The resin composition according to [4], wherein the aromatic ring in the benzocyclobutene structure contains the functional group (β). [6] The resin composition according to any one of [1] to [5], wherein the radical polymerization initiator (B) contains bibenzyl compounds. [7] The copolymer (A) is one or more repeating units (a) derived from olefins represented by the following formula (I), one or more repeating units (b) derived from cyclic non-conjugated dienes represented by the following formula (III), one or more repeating units (c) derived from cyclic olefins represented by the following formula (V), The resin composition according to any one of [1] to [6], containing [Chemical formula] (In the above formula (I), R300 represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 29 carbon atoms)

Chemical formula

Chemical formula

[10] A prepreg obtained by impregnating a fiber base material with the resin composition according to any one of [1] to [8] or the varnish according to [9].

[11] A thermosetting cyclic olefin copolymer (A) having a functional group (α) that can be used in a crosslinking reaction, A radical polymerization initiator (B), A crosslinking agent (C) having a benzocyclobutene structure, A cured product of a resin composition containing A cured product in which the amount of residues derived from a peroxide-based polymerization initiator is less than 0.3% by mass.

[12] A film containing a cured product of the resin composition according to any one of [1] to [8] or the cured product according to

[11] .

[13] A laminate containing the prepreg according to

[10] or the film according to

[12] .

[14] A metal-clad laminate containing a metal foil on at least one side of the laminate according to

[13] .

[15] A printed wiring board manufactured using the prepreg according to

[10] or the metal-clad laminate according to

[14] .

[16] An electronic device containing the film according to

[12] or the printed wiring board according to

[15] .

[17] The electronic device according to

[16] , wherein the electronic device includes a high-speed communication-compatible module. [Effect of the Invention]

[0009] According to the present invention, it is possible to obtain a prepreg, a film, a laminate, a metal-clad laminate, a printed wiring board, and an electronic device in which the performance balance of low dielectric characteristics and low thermal expansion is improved, a resin composition, a varnish, and a cured product, and it is possible to provide a prepreg, a cured product, a film, a laminate, a metal-clad laminate, a printed wiring board, and an electronic device in which the performance balance of low dielectric characteristics and low thermal expansion is improved. [Mode for Carrying Out the Invention]

[0010] Hereinafter, the present invention will be described based on embodiments. In this embodiment, "A~B" indicating a numerical range represents A or more and B or less unless otherwise specified. Further, when the numerical range is described stepwise, the upper and lower limits of each numerical range can be arbitrarily combined.

[0011] [Resin composition] The resin composition of this embodiment is a resin composition containing a thermosetting cyclic olefin copolymer (A) having a functional group (α) that can be used in a crosslinking reaction, a radical polymerization initiator (B), and a crosslinking agent (C) having a benzocyclobutene structure, wherein the content of the peroxide-based polymerization initiator is less than 50 parts by mass with respect to 100 parts by mass of the radical polymerization initiator (B).

[0012] For resin compositions used in printed wiring boards and electronic devices, an improvement in the performance balance is required in terms of low thermal expansion and low dielectric properties. According to the resin composition of this embodiment, a prepreg, film, laminate, metal-clad laminate, printed wiring board, and electronic device with an improved performance balance of low dielectric properties and low thermal expansion can be obtained. The reason is considered as follows. First, since the crosslinking agent (C) having a benzocyclobutene structure has a hydrocarbon as its basic skeleton, it has good compatibility with the thermosetting cyclic olefin copolymer (A). Furthermore, the structure formed during the crosslinking reaction of the benzocyclobutene structure is considered to be advantageous for suppressing thermal expansion. Therefore, it is considered that the low thermal expansion property can be improved by combining the thermosetting cyclic olefin copolymer (A) and the crosslinking agent (C) having a benzocyclobutene structure. In addition, the amount of reaction residues of the peroxide-based polymerization initiator, which causes deterioration of the dielectric properties, can be made less than a certain amount. As a result, it is considered that the low dielectric property can be improved. For the above reasons, according to the resin composition of this embodiment, it is considered that the performance balance of low dielectric properties and low thermal expansion can be improved.

[0013] [Thermosetting cyclic olefin copolymer (A)] The resin composition of this embodiment contains a thermosetting cyclic olefin copolymer (A) having a functional group (α) that can be used in a crosslinking reaction (hereinafter, also simply referred to as "copolymer (A)"). The thermosetting cyclic olefin copolymer (A) can be used without particular limitation as long as it is a copolymer having thermosetting properties and containing repeating units derived from cyclic olefins. Further, from the viewpoint of improving the heat resistance of the cured product obtained by forming a crosslinked structure, the thermosetting cyclic olefin copolymer (A) has a functional group (α) that can be used in a crosslinking reaction. Examples of the functional group (α) include crosslinkable functional groups such as vinyl group; vinylidene group; vinylene group; vinyl group substituted with an alkyl group, phenyl group or alkylphenyl group; vinylidene group substituted with an alkyl group, phenyl group or alkylphenyl group; vinylene group substituted with an alkyl group, phenyl group or alkylphenyl group; maleimide group; thiol group; thienyl group; silyl group; epoxy group; oxazoline group; (meth)acrylic group; carboxyl group, etc., and a vinyl group is preferred. Since the thermosetting cyclic olefin copolymer (A) has the functional group (α), a crosslinked structure can be formed with a crosslinking agent (C) having a benzocyclobutene structure described later, and the low thermal expansion property can be further improved. Hereinafter, the thermosetting cyclic olefin copolymer (A) will be described in detail, but the thermosetting cyclic olefin copolymer (A) used in this embodiment is not limited to the following aspects.

[0014] From the viewpoint of further improving the performance balance of the low dielectric property and low thermal expansion property of the obtained cured product, the thermosetting cyclic olefin copolymer (A) one or more repeating units (a) derived from olefins represented by the following formula (I), one or more repeating units (b) derived from cyclic non-conjugated dienes represented by the following formula (III), one or more repeating units (c) derived from cyclic olefins represented by the following formula (V), and preferably contains them.

[0015] [Chemical formula]

[0016] In the above formula (I), R 300 represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 29 carbon atoms.

[0017] [Chemical formula]

[0018] In the above formula (III), u is 0 or 1, v is 0 or a positive integer, preferably an integer of 0 or more and 2 or less, more preferably 0 or 1, w is 0 or 1, R 61 ~R 76 and R a1 and R b1 may be the same as or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms or an aromatic hydrocarbon group having 6 to 20 carbon atoms, R 104 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, t is a positive integer of 0 to 10, R 75 and R 76 may be bonded to each other to form a monocyclic or polycyclic ring.

[0019] [Chemical formula]

[0020] In the above formula (V), u is 0 or 1, v is 0 or a positive integer, preferably an integer of 0 or more and 2 or less, more preferably 0 or 1, w is 0 or 1, R 61 ~R 78 and R a1 and R b1may be the same as or different from each other, and is a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms or an aromatic hydrocarbon group having 6 to 20 carbon atoms, R 75 ~R 78 may be bonded to each other to form a monocyclic or polycyclic ring.

[0021] In the thermosetting cyclic olefin copolymer (A), when the total number of moles of the repeating units in the thermosetting cyclic olefin copolymer (A) is 100 mol%, the content of each repeating unit can be as follows. The content of the repeating unit (a) derived from an olefin is preferably 35 mol% or more, more preferably 40 mol% or more, still more preferably 45 mol% or more, still more preferably 50 mol% or more, still more preferably 55 mol% or more, still more preferably 60 mol% or more, and preferably 85 mol% or less, more preferably 80 mol% or less, more preferably 75 mol% or less, still more preferably 72 mol% or less, still more preferably 68 mol% or less, still more preferably 65 mol% or less. Also, the content of the repeating unit (b) derived from a cyclic non-conjugated diene is preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 15 mol% or more, still more preferably 20 mol% or more, and preferably 55 mol% or less, more preferably 50 mol% or less, still more preferably 45 mol% or less, still more preferably 40 mol% or less, still more preferably 35 mol% or less, still more preferably 30 mol% or less. Furthermore, the content of the repeating unit (c) derived from a cyclic olefin is preferably 1 mol% or more, more preferably 2 mol% or more, still more preferably 3 mol% or more, still more preferably 4 mol% or more, still more preferably 5 mol% or more, still more preferably 6 mol% or more, still more preferably 7 mol% or more, and preferably 25 mol% or less, more preferably 20 mol% or less, still more preferably 15 mol% or less. When the content of each repeating unit in the thermosetting cyclic olefin copolymer (A) is within the above range, when made into a film, the performance balance of low dielectric properties and low thermal expansion can be further improved. Furthermore, the performance balance of the mechanical properties, transparency, and gas barrier properties of the film can be further improved. In other words, a film excellent in the balance of these physical properties can be obtained.

[0022] The olefin monomer, which is one of the copolymerization raw materials of the thermosetting cyclic olefin copolymer (A), is a monomer that undergoes addition copolymerization to give the skeleton represented by the above formula (I), and is an olefin represented by the following formula (Ia).

[0023]

Chemical formula

[0024] In the above formula (Ia), R 300 represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 29 carbon atoms. Examples of the olefin represented by the formula (Ia) include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. From the viewpoint of further improving the performance balance of heat resistance, mechanical properties, dielectric properties, transparency, and gas barrier properties when made into a film, among these, at least one selected from the group consisting of ethylene and propylene is preferable, and ethylene is more preferable. Two or more kinds of the olefin monomers represented by the above formula (Ia) may be used. Also, as the olefin, it may contain at least one biomass-derived monomer (biomass-derived ethylene, biomass-derived propylene, etc.).

[0025] The cyclic non-conjugated diene monomer, which is one of the copolymerization raw materials of the thermosetting cyclic olefin-based copolymer (A), undergoes addition copolymerization to form the repeating unit represented by the above formula (III). For example, a cyclic non-conjugated diene represented by the following formula (IIIa) corresponding to the above formula (III) is used. The cyclic non-conjugated diene may contain a structural unit derived from a biomass-derived monomer (cyclic non-conjugated diene).

[0026] [Chemical formula]

[0027] In the above formula (IIIa), u is 0 or 1, v is 0 or a positive integer, preferably an integer of 0 or more and 2 or less, more preferably 0 or 1, w is 0 or 1, and R 61 ~R 76 as well as R a1 and R b1 may be the same as or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms. R 104 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, t is a positive integer of 0 to 10, and R 75 and R 76 may be bonded to each other to form a monocyclic or polycyclic ring.

[0028] The cyclic non-conjugated diene represented by the above formula (IIIa) is not particularly limited, and examples thereof include cyclic non-conjugated dienes represented by the following chemical formulas. Among these, as the cyclic non-conjugated diene represented by the above formula (IIIa), at least one selected from the group consisting of 5-vinyl-2-norbornene and 8-vinyl-9-methyltetracyclo[4.4.0.1 2,5 .1 7,10 -3-dodecene is preferable, and 5-vinyl-2-norbornene is more preferable.

[0029] [Chemical formula]

[0030]

Chem.

[0031] The cyclic non-conjugated diene represented by the above formula (IIIa) can also be represented, for example, by the following formula (IIIb).

[0032]

Chem.

[0033] In the above formula (IIIb), n is an integer from 0 to 10, R1 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R2 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

[0034] The thermosetting cyclic olefin copolymer (A) is characterized by having a double bond in the side chain portion, that is, the portion other than the main chain of the copolymerization, by including a repeating unit derived from the cyclic non-conjugated diene represented by the above formula (III).

[0035] The cyclic olefin monomer, which is one of the copolymerization raw materials of the thermosetting cyclic olefin copolymer (A), undergoes addition copolymerization to form a repeating unit represented by the above formula (V). For example, a cyclic olefin monomer represented by the following formula (Va) corresponding to the above formula (V) is used.

[0036]

Chem.

[0037] In the above formula (Va), u is 0 or 1, v is 0 or a positive integer, preferably an integer of 0 or more and 2 or less, more preferably 0 or 1, w is 0 or 1, R 61 ~R 78 as well as R a1 and R b1may be the same as or different from each other, and is a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, and R 75 ~R 78 may be bonded to each other to form a monocyclic or polycyclic ring.

[0038] As specific examples of the cyclic olefin represented by the above formula (Va), the compounds described in International Publication No. 2006 / 118261 can be used. As the cyclic olefin represented by the above formula (Va), bicyclo[2.2.1]-2-heptene (also referred to as "norbornene") and tetracyclo[4.4.0.1 2,5 .1 7,10 -3-dodecene (also referred to as "tetracyclododecene") are preferably at least one selected from the group consisting of, and tetracyclo[4.4.0.1 2,5 .1 7,10 -3-dodecene is more preferable. Since these cyclic olefins have a rigid ring structure, the elastic modulus of the copolymer and the cured product is easily maintained, and since they do not contain a hetero double bond structure, there is an advantage that crosslinking control is easy. As the cyclic olefin represented by the above formula (Va), it may contain a structural unit derived from a biomass-derived monomer (cyclic olefin).

[0039] By using the olefin monomer represented by the above formula (Ia) and the cyclic olefin monomer represented by the above formula (Va) as the copolymerization component, the solubility of the thermosetting cyclic olefin-based copolymer (A) in a solvent is further improved, so that the moldability is good and the product yield is improved.

[0040] The thermosetting cyclic olefin copolymer (A) may further contain at least one repeating unit selected from the group consisting of a repeating unit (a) derived from one or more olefins represented by the above formula (I), a repeating unit (b) derived from a cyclic non-conjugated diene represented by the above formula (III), a repeating unit (c) derived from one or more cyclic olefins represented by the above formula (V), a repeating unit derived from a cyclic olefin other than the cyclic non-conjugated diene represented by the above formula (III) and the cyclic olefin represented by the above formula (V), and a repeating unit derived from a chain polyene. In this case, as copolymerization raw materials of the thermosetting cyclic olefin copolymer (A), in addition to an olefin monomer represented by the formula (Ia), a cyclic non-conjugated diene monomer represented by the formula (IIIa), and a cyclic olefin monomer represented by the formula (Va), a cyclic olefin monomer other than the cyclic non-conjugated diene monomer represented by the formula (IIIa) and the cyclic olefin monomer represented by the formula (Va), and / or a chain polyene monomer can be used. Examples of such cyclic olefin monomers and chain polyene monomers include a cyclic olefin represented by the following formula (VIa), a cyclic olefin represented by the following formula (VIIa), a chain polyene represented by the following formula (VIIIa), etc. Two or more different kinds of these cyclic olefins and chain polyenes may be used.

[0041]

Chemical formula

[0042] In the above formula (VIa), x and d are 0 or integers of 1 or more, preferably integers of 0 or more and 2 or less, more preferably 0 or 1, y and z are 0, 1 or 2, and R 81 ~R 99 may be the same as or different from each other, and are a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group which is an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 15 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms or an alkoxy group, and the carbon atom to which R 89 and R 90 are bonded, and R93 The carbon atom to which it is attached or R 91 The carbon atom to which it is attached may be attached directly or via an alkylene group having 1 to 3 carbon atoms. Also, when y = z = 0, R 95 and R 92 or R 95 and R 99 may be bonded to each other to form a monocyclic or polycyclic aromatic ring.

[0043]

Chemical formula

[0044] In the above formula (VIIa), R 100 and R 101 may be the same as or different from each other, and represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and f satisfies 1 ≦ f ≦ 18.

[0045]

Chemical formula

[0046] In the above formula (VIIIa), R 201 to R 206 may be the same as or different from each other, and are a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and P is a linear or branched hydrocarbon group having 1 to 20 carbon atoms, which may contain a double bond and / or a triple bond.

[0047] As specific examples of the cyclic olefins represented by the above formula (VIa) and the above formula (VIIa), the compounds described in paragraphs 0037 to 0063 of International Publication No. 2006 / 118261 can be used.

[0048] Examples of the chain polyene represented by the above formula (VIIIa) include 1,4 - hexadiene, 3 - methyl - 1,4 - hexadiene, 4 - methyl - 1,4 - hexadiene, 5 - methyl - 1,4 - hexadiene, 4,5 - dimethyl - 1,4 - hexadiene, 7 - methyl - 1,6 - octadiene, DMDT, 1,3 - butadiene, 1,5 - hexadiene, etc. Also, cyclic polyenes cyclized from polyenes such as 1,3 - butadiene and 1,5 - hexadiene may be used.

[0049] When the thermosetting cyclic olefin - based copolymer (A) contains a repeating unit derived from the chain polyene represented by the above formula (VIIIa), or a repeating unit derived from a cyclic non - conjugated diene represented by the above formula (III) and a cyclic olefin other than the cyclic olefin represented by the above formula (V) [for example, the above formula (VIa), the above formula (VIIa)], the content of the repeating unit is, for example, 0.1 mol% or more and 100 mol% or less, preferably 0.1 mol% or more and 50 mol% or less, based on the total number of moles of the repeating unit (a) derived from one or more olefins represented by the above formula (I), the repeating unit (b) derived from one or more cyclic non - conjugated dienes represented by the above formula (III), and the repeating unit (c) derived from one or more cyclic olefins represented by the above formula (V).

[0050] By using, as the copolymerization components, the olefin monomer represented by the above formula (Ia), the cyclic olefin represented by the formula (VIa) or (VIIa), and the chain polyene represented by the above formula (VIIIa) described above, the effects of the present embodiment can be obtained, and the solubility of the thermosetting cyclic olefin - based copolymer (A) in a solvent is further improved, so that the moldability becomes good and the product yield is improved. Among these, the cyclic olefin represented by the formula (VIa) or (VIIa) is preferred. Since these cyclic olefins have a rigid ring structure, the elastic modulus of the thermosetting cyclic olefin - based copolymer (A) and the film is easily maintained, and since they do not contain a hetero - double - bond structure, there is an advantage that cross - linking control is easy.

[0051] The number average molecular weight (Mn) in terms of polystyrene, measured by gel permeation chromatography of the thermosetting cyclic olefin copolymer (A), is preferably 5,000 or more, more preferably 10,000 or more, still more preferably 15,000 or more, still more preferably 20,000 or more, from the viewpoint of further improving the performance balance of dielectric properties, low thermal expansibility, and mechanical properties. Also, from the viewpoint of further improving moldability such as impregnation property into the fiber base material and wiring embedding property during the production of printed wiring boards, it is preferably 100,000 or less, more preferably 80,000 or less, still more preferably 60,000 or less, still more preferably 40,000 or less, still more preferably 30,000 or less. The number average molecular weight (Mn) of the thermosetting cyclic olefin copolymer (A) can be controlled by polymerization conditions such as polymerization catalysts, cocatalysts, H2 addition amount, and polymerization temperature.

[0052] The content of the thermosetting cyclic olefin copolymer (A) in the resin composition of the present embodiment, when the entire resin composition is 100% by mass, is preferably 35% by mass or more, more preferably 40% by mass or more, still more preferably 45% by mass or more, still more preferably 50% by mass or more, still more preferably 55% by mass or more, still more preferably 60% by mass or more, still more preferably 65% by mass or more, from the viewpoint of further improving the performance balance of low thermal expansibility, mechanical properties, and low dielectric properties of the cured product. And it is preferably 96% by mass or less, more preferably 94% by mass or less, still more preferably 92% by mass or less, still more preferably 90% by mass or less, still more preferably 88% by mass or less.

[0053] <Method for Producing Thermosetting Cyclic Olefin Copolymer (A)> The thermosetting cyclic olefin copolymer (A) of the present embodiment can be produced, for example, according to the method for producing cyclic olefin copolymers described in paragraphs 0075 to 0219 of International Publication No. 2012 / 046443. Details are omitted here.

[0054] <Radical Polymerization Initiator (B)> The resin composition of this embodiment contains a radical polymerization initiator (B). Further, the amount of the residue derived from the peroxide-based polymerization initiator in the cured product of the resin composition is preferably less than 0.3% by mass, more preferably less than 0.1% by mass. Furthermore, from the viewpoints of facilitating the amount of the residue to be less than 0.3% by mass and further improving the low dielectric characteristics, the content of the peroxide-based polymerization initiator in the resin composition of this embodiment is less than 50 parts by mass, preferably less than 30 parts by mass, more preferably less than 20 parts by mass, still more preferably less than 10 parts by mass, still more preferably less than 5 parts by mass, still more preferably less than 1 part by mass, still more preferably less than 0.5 part by mass, still more preferably less than 0.1 part by mass, still more preferably less than 0.01 part by mass with respect to 100 parts by mass of the radical polymerization initiator (B). It is even more preferable that the resin composition of this embodiment does not contain a peroxide-based polymerization initiator. For the crosslinking by the radical polymerization initiator (B), the crosslinking method by a normal radical polymerization initiator applied to polyolefin or the like can be directly applied. That is, a radical polymerization initiator is blended with the thermosetting cyclic olefin copolymer (A) and heated and crosslinked.

[0055] As the radical polymerization initiator (B), known thermal radical polymerization initiators, photo radical polymerization initiators, and combinations thereof can be used. Among these radical polymerization initiators, when a thermal radical polymerization initiator is used, the half-life temperature for 10 hours is, for example, 80°C or higher, preferably 120°C or higher from the viewpoint of storage stability. Examples of such thermal radical polymerization initiators include bibenzyl compounds such as hexaphenylethane, 1-tert-butyl-3-[2-(4-tert-butylphenyl)-1,1,2-trimethylpropyl]benzene, 2,3-dimethyl-2,3-diphenylbutane; and 3,3,5,7,7-pentamethyl-1,2,4-trioxepane and the like.

[0056] Among the radical polymerization initiators (B), examples of the photo-radical polymerization initiators include benzoin alkyl ethers, benzyldimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzophenone, methyl benzoyl formate, isopropyl thioxanthone, and mixtures of two or more of these. Further, a sensitizer can be used together with these photo-radical polymerization initiators. Examples of the sensitizer include carbonyl compounds such as anthraquinone, 1,2-naphthoquinone, 1,4-naphthoquinone, benzanthrone, p,p'-tetramethyldiaminobenzophenone enone, chloranil; nitro compounds such as nitrobenzene, p-dinitrobenzene, 2-nitrofluorene; aromatic hydrocarbons such as anthracene, chrysene; sulfur compounds such as diphenyl disulfide; nitrogen compounds such as nitroaniline, 2-chloro-4-nitroaniline, 5-nitro-2-aminotoluene, tetracyanoethylene, and the like. Among these radical polymerization initiators (B), it is preferable to contain a thermal radical polymerization initiator, more preferably to contain bibenzyl compounds, still more preferably to contain at least one selected from the group consisting of hexaphenylethane, 1-tert-butyl-3-[2-(4-tert-butylphenyl)-1,1,2-trimethylpropyl]benzene, and 2,3-dimethyl-2,3-diphenylbutane, and still more preferably to contain 2,3-dimethyl-2,3-diphenylbutane.

[0057] From the viewpoint of further improving the performance balance of low dielectric properties and low thermal expansion of the obtained cured product, the content of the radical polymerization initiator (B) in the resin composition of the present embodiment is preferably 0.5 part by mass or more, more preferably 1.0 part by mass or more, still more preferably 1.5 part by mass or more, still more preferably 2.0 part by mass or more, still more preferably 2.5 part by mass or more, and preferably 8.0 part by mass or less, more preferably 7.0 part by mass or less, still more preferably 6.0 part by mass or less, still more preferably 5.0 part by mass or less, still more preferably 4.0 part by mass or less, based on 100 parts by mass of the thermosetting cyclic olefin copolymer (A).

[0058] The resin composition of this embodiment can further contain a crosslinking aid. There is no limitation on the crosslinking aid. For example, oximes such as p-quinonedioxime and p,p'-dibenzoylquinonedioxime; acrylates or methacrylates such as ethylene dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, cyclohexyl methacrylate, acrylic acid / zinc oxide mixture, allyl methacrylate; vinyl monomers such as divinylbenzene, vinyltoluene, vinylpyridine; allyl compounds such as hexamethylenedialllyl nadimide, diallyl itaconate, diallyl phthalate, diallyl isophthalate, diallyl monoglycidyl isocyanurate, triallyl cyanurate, triallyl isocyanurate; maleimide compounds such as N,N'-m-phenylene bismaleimide, N,N'-(4,4'-methylenediphenylene) dimaleimide and the like can be mentioned. These crosslinking aids can be used alone or in combination.

[0059] <Crosslinking agent (C) having a benzocyclobutene structure> The resin composition of this embodiment contains a crosslinking agent (C) having a benzocyclobutene structure (hereinafter, also simply referred to as crosslinking agent (C)). Here, the benzocyclobutene structure refers to, for example, the structure represented by the following formula. R in the following formula 1 ~R 6 may be the same as or different from each other, preferably a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group which is an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 15 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, more preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, still more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and still more preferably a hydrogen atom. Also, at least one of R 1 ~R 6 represents a bond, preferably R 1 ~R 6One of them represents a linking group, more preferably R 1 ~R 4 One of them represents a linking group, even more preferably R 2 and R 3 One of them represents a linking group.

[0060] [Chemical formula]

[0061] As the crosslinking agent (C), there is no particular limitation as long as it is a compound having the above structure in the molecule, and it can be used. For example, it may be an acrylate compound, a methacrylate compound, a maleimide compound, an acrylamide compound, acrylonitrile, maleic anhydride, a styrene compound, a vinyl compound, etc. having a benzocyclobutene structure.

[0062] Among them, from the viewpoint of facilitating the formation of a crosslinked structure with the copolymer (A), it is preferable that the crosslinking agent (C) has one or more functional groups (β) that can be used in the crosslinking reaction. Examples of the functional group (β) include a vinyl group; a vinylidene group; a vinylene group; a vinyl group substituted with an alkyl group, a phenyl group or an alkylphenyl group; a vinylidene group substituted with an alkyl group, a phenyl group or an alkylphenyl group; a vinylene group substituted with an alkyl group, a phenyl group or an alkylphenyl group; a maleimide group; a thiol group; a thienyl group; a silyl group; an epoxy group; an oxazoline group; a (meth)acrylic group; a crosslinkable functional group such as a carboxyl group, and preferably a vinyl group. When the crosslinking agent (C) has a functional group (β), from the viewpoint of facilitating the formation of a crosslinked structure with the copolymer (A), it is preferable that the aromatic ring in the benzocyclobutene structure contains the functional group (β).

[0063] Examples of the crosslinking agent (C) include 4-vinylbenzocyclobutene, 4-dimethylvinylsilylbenzocyclobutene, 1-dimethylvinylsilylbenzocyclobutene, 4-acrylylbenzocyclobutene, 1-acrylylbenzocyclobutene, etc. Since the aromatic ring in the benzocyclobutene structure contains the functional group (β), 4-vinylbenzocyclobutene, 4-dimethylvinylsilylbenzocyclobutene, and 4-acrylylbenzocyclobutene are more preferable, and 4-vinylbenzocyclobutene is even more preferable from the viewpoint of availability.

[0064] The compound having a benzocyclobutene structure in the molecule that can be used as the crosslinking agent (C) can be synthesized by a known method as reported by Kirchhoff et al. (PCT.Int.Appl. (1987), WO87 / 05303, pp. 113) and Endo et al. (Journal of Polymer Science, Part A: Polymer Chemistry (1995), 33(4), pp. 707-15).

[0065] The content of the crosslinking agent (C) in the resin composition of the present embodiment is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, based on 100 parts by mass of the copolymer (A). When the content of the crosslinking agent (C) is at least the above lower limit value, the low thermal expansibility of the resin composition can be further improved. Also, when the content of the crosslinking agent (C) is at most the above upper limit value, the crosslinkability of the resin composition can be improved, and as a result, the heat resistance can be improved. The content of the crosslinking agent (C) in the resin composition of the present embodiment is more preferably 2 to 25 parts by mass, and even more preferably 3 to 10 parts by mass, based on 100 parts by mass of the copolymer (A).

[0066] In the resin composition of the present embodiment, the total content of the thermosetting cyclic olefin copolymer (A), the radical polymerization initiator (B), and the crosslinking agent (C) having a benzocyclobutene structure is calculated based on the total amount of the solid content of the resin composition (the total amount of the components remaining as solids when cured) being 100% by mass. From the perspective of further improving the performance balance of low dielectric properties and low thermal expansion, and from the perspective of achieving a good balance between mechanical strength and processability, it is preferably 50% by mass or more, more preferably 55% by mass or more, still more preferably 60% by mass or more, still more preferably 70% by mass or more, still more preferably 80% by mass or more, still more preferably 90% by mass or more, and preferably 100% by mass or less.

[0067] <Other components> The resin composition of the present embodiment may contain other components as long as it does not prevent the effects of the invention of the present embodiment. Examples of other components include at least one additive selected from the group consisting of antioxidants, heat stabilizers, weather stabilizers, radiation-resistant agents, plasticizers, lubricants, mold release agents, nucleating agents, friction and wear improvers, flame retardants, foaming agents, antistatic agents, colorants, antifogging agents, antiblocking agents, impact-resistant agents, surface wettability improvers, organic fillers, inorganic fillers, hydrochloric acid absorbers, and metal deactivators, as well as resins other than the thermosetting cyclic olefin copolymer (A) such as epoxy resins, polystyrene resins, and polyphenylene ether (PPE) resins, and crosslinking agents other than the crosslinking agent (C) having a benzocyclobutene structure.

[0068] <Method for preparing the resin composition> The resin composition of the present embodiment can be prepared by mixing the thermosetting cyclic olefin copolymer (A), the radical polymerization initiator (B), and the crosslinking agent (C) having a benzocyclobutene structure, and optionally other components. As the mixing method, a method of melt blending using an extruder or the like, or a solution blending method in which the components are dissolved and dispersed in a suitable solvent such as saturated hydrocarbons like heptane, hexane, decane, cyclohexane; aromatic hydrocarbons like toluene, benzene, xylene, etc. can be employed.

[0069] Hereinafter, the physical properties of the cured product of the resin composition of the present embodiment will be described.

[0070] In the cured product of the resin composition of the present embodiment, the dielectric tangent Df, from the viewpoint of further improving the performance balance of low dielectric characteristics and low thermal expansion, at a frequency of 10 GHz, is preferably 0.00100 or less, more preferably 0.00080 or less, still more preferably 0.00065 or less, and even more preferably 0.00060 or less. There is no limitation on the lower limit of the dielectric tangent Df, but for example, it may be 0.00010 or more, may be 0.00030 or more, may be 0.00050 or more. The dielectric tangent Df in the cured product of the resin composition of the present embodiment is the dielectric tangent Df at 10 GHz measured by the method described in the examples below.

[0071] The linear expansion coefficient of the cured product of the resin composition of the present embodiment in the range of 25 to 90 °C (1 st run) is preferably less than 80 ppm / K, more preferably 79 ppm / K or less, still more preferably 78 ppm / K or less, from the viewpoint of further reducing the thermal expansibility. The linear expansion coefficient of the cured product of the resin composition of the present embodiment in the range of 25 to 90 °C (1 st There is no limitation on the lower limit of the linear expansion coefficient in the range of run), but for example, it may be 1 ppm / K or more, may be 5 ppm / K or more, may be 10 ppm / K or more, may be 15 ppm / K or more.

[0072] The linear expansion coefficient of the cured product of the resin composition of the present embodiment in the range of 160 to 280 °C (2 nd run) is preferably less than 140 ppm / K, more preferably 135 ppm / K or less, from the viewpoint of further reducing the thermal expansibility. The linear expansion coefficient of the cured product of the resin composition of the present embodiment in the range of 160 to 280 °C (2 ndThere is no limitation on the lower limit of the linear expansion coefficient in the range of run), but it may be, for example, 1 ppm / K or more, 5 ppm / K or more, 10 ppm / K or more, or 15 ppm / K or more. The linear expansion coefficient is measured by the method described in the examples below.

[0073] The cured product of the resin composition of the present embodiment used for measuring the above various physical properties is produced by the method described in the examples below.

[0074] [Varnish] The resin composition of the present embodiment can be made into a varnish by mixing with a solvent. The solvent for preparing the varnish is not limited as long as it does not impair the solubility or affinity for the thermosetting cyclic olefin copolymer (A), the radical polymerization initiator (B), and the crosslinking agent (C) having a benzocyclobutene structure. Preferably, the solvent is a saturated hydrocarbon such as heptane, hexane, octane, decane; an alicyclic hydrocarbon such as cyclohexane, methylcyclohexane, decahydronaphthalene; an aromatic hydrocarbon such as toluene, benzene, xylene, mesitylene, pseudocumene; an alcohol such as methanol, ethanol, isopropyl alcohol, butanol, pentanol, hexanol, propanediol, phenol; a ketone solvent such as acetone, methyl isobutyl ketone, methyl ethyl ketone, pentanone, hexanone, cyclohexanone, isophorone, acetophenone; a cellosolve such as methyl cellosolve, ethyl cellosolve; an ester such as methyl acetate, ethyl acetate, butyl acetate, methyl propionate, butyl formate; a halogenated hydrocarbon such as trichloroethylene, dichloroethylene, chlorobenzene, etc. From the viewpoint of further improving the solubility and availability of the resin composition, heptane, decane, cyclohexane, methylcyclohexane, decahydronaphthalene, toluene, benzene, xylene, mesitylene, pseudocumene are more preferably used. These solvents can be used alone or in combination of two or more in any ratio. As the amount of the solvent added to the resin composition, from the viewpoint of further improving the handleability and coatability of the varnish, when the total amount of the resin composition is 100 parts by mass, it is preferably 100 parts by mass or more, more preferably 120 parts by mass or more, and preferably 500 parts by mass or less, more preferably 450 parts by mass or less, still more preferably 400 parts by mass or less. In addition, the total content of the thermosetting cyclic olefin copolymer (A), the radical polymerization initiator (B), and the crosslinking agent (C) having a benzocyclobutene structure in the varnish is preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, and preferably less than 100% by mass.

[0075] In this embodiment, as a method for producing the varnish, it may be carried out by any method. For example, it includes a step of mixing the resin composition and the solvent. There is no limitation on the order of mixing of each component, and it can be carried out by any method such as batchwise or divided. There is also no limitation on the apparatus for preparing the varnish, and it may be carried out by any batch-type or continuous-type apparatus capable of stirring and mixing. The temperature at the time of preparing the varnish can be arbitrarily selected within the range from room temperature to the boiling point of the solvent. Note that the varnish may be prepared by directly using the reaction solution obtained when the thermosetting cyclic olefin copolymer (A) is obtained as the solvent.

[0076] [Cured product] The cured product can be obtained by crosslinking the thermosetting cyclic olefin copolymer (A) in the resin composition of this embodiment. The crosslinking can be carried out, for example, by a crosslinking step of crosslinking the resin composition under a vacuum of 20 kPa or less at a temperature of 150°C or higher with a press pressure of 0.2 MPa or higher. In the crosslinking process, the crosslinking temperature is preferably 150 °C or higher, more preferably 160 °C or higher, still more preferably 170 °C or higher, from the viewpoint of further improving the heat resistance of the resulting cured product, and preferably 280 °C or lower, more preferably 260 °C or lower, still more preferably 250 °C or lower, still more preferably 240 °C or lower, from the viewpoint of suppressing thermal decomposition of the thermosetting cyclic olefin copolymer (A) and the cured product. The press pressure in the crosslinking process is 0.2 MPa or higher, preferably 1 MPa or higher, more preferably 2 MPa or higher, still more preferably 3 MPa or higher, from the viewpoint of ensuring the uniformity of the resulting cured product. The degree of vacuum in the crosslinking process is carried out under a vacuum of 20 kPa or lower, preferably under a vacuum of 10 kPa or lower, more preferably under a vacuum of 5 kPa or lower, still more preferably under a vacuum of 2 kPa or lower, from the viewpoint of maintaining the dielectric properties of the resulting cured product.

[0077] The crosslinking process can be carried out in a molten state of the resin composition of the present embodiment, or in a solution state in which the resin composition is dissolved or dispersed in a solvent. Further, the crosslinking process can also be carried out by volatilizing the solvent from a solution state in which the resin composition is dissolved in a solvent, forming it into an arbitrary form such as a film or a coating, and then further proceeding with the crosslinking reaction. When the reaction is carried out in a molten state, a kneading device such as a mixing roll, a Banbury mixer, an extruder, a kneader, or a continuous mixer is used to melt-knead the mixture of raw materials and cause a reaction. Further, the crosslinking reaction can also be further advanced after molding by an arbitrary method. As the solvent used when the reaction is carried out in a solution state, the same solvent as that used in the above solution blending method can be used.

[0078] Further, the cured product of the present embodiment is a cured product of a resin composition containing a thermosetting cyclic olefin copolymer (A) having a functional group (α) that can be used in a crosslinking reaction, a radical polymerization initiator (B), and a crosslinking agent (C) having a benzocyclobutene structure, and may be a cured product in which the amount of residues derived from a peroxide-based polymerization initiator is less than 0.3% by mass. The amount of residues derived from the peroxide-based polymerization initiator in the cured product of the present embodiment is preferably less than 0.3% by mass, more preferably less than 0.1% by mass.

[0079] [Prepreg] The prepreg of the present embodiment is obtained by impregnating a fiber base material with the resin composition or the varnish of the present embodiment, and is preferably formed by laminating the resin composition of the present embodiment and a sheet-like fiber base material. The method for producing the prepreg is not particularly limited, and various known methods can be applied. For example, a method including a step of impregnating the above-described varnish into a sheet-like fiber base material to obtain an impregnated body, and a step of heating the obtained impregnated body to dry the solvent contained in the varnish can be mentioned. The impregnation of the varnish into the sheet-like fiber base material can be performed, for example, by applying a predetermined amount of the varnish to the sheet-like fiber base material by a known method such as a spray coating method, a dip coating method, a roll coating method, a curtain coating method, a die coating method, or a slit coating method, overlaying a protective film thereon if necessary, and pressing it with a roller or the like from above. Further, the step of heating the impregnated body to dry the solvent contained in the varnish is not particularly limited, and examples thereof include drying in air or nitrogen by a batch-type air dryer, or drying by passing through a heating furnace in a continuous process. After impregnating the varnish into the sheet-like fiber base material, the obtained impregnated body is heated to a predetermined temperature, whereby the solvent contained in the varnish evaporates and a prepreg is obtained.

[0080] As the fibers constituting the sheet-like fiber base material, inorganic or organic fibers can be used, and there is no particular limitation. For example, organic fibers such as PET (polyethylene terephthalate) fibers, polystyrene fibers, aramid fibers, ultra-high molecular weight polyethylene fibers, polyamide (nylon) fibers, and liquid crystal polyester fibers; inorganic fibers such as glass fibers, carbon fibers, alumina fibers, tungsten fibers, molybdenum fibers, titanium fibers, steel fibers, boron fibers, silicon carbide fibers, and silica fibers; etc. can be mentioned. Among these, it is preferably at least one selected from the group consisting of organic fibers and glass fibers, and more preferably at least one selected from the group consisting of aramid fibers, liquid crystal polyester fibers, and glass fibers. Examples of glass fibers include E glass, NE glass, S glass, D glass, H glass, T glass, etc. The impregnation of the varnish into the sheet-like fiber base material is carried out, for example, by dipping and coating. The impregnation may be repeated a plurality of times as necessary. These sheet-like fiber base materials can be used individually or in combination of two or more, and the amount used is appropriately selected as desired. However, in the prepreg or laminate, for example, it is 10% by mass or more, preferably 20% by mass or more, more preferably 30% by mass or more, and also, for example, 90% by mass or less, preferably 80% by mass or less, more preferably 70% by mass or less. Within this range, the dielectric properties and mechanical strength of the obtained laminate are highly balanced, which is suitable.

[0081] The thickness of the prepreg is appropriately selected according to the purpose of use. For example, it is 0.001 mm or more, preferably 0.005 mm or more, more preferably 0.01 mm or more, and also, for example, 10 mm or less, preferably 1 mm or less, more preferably 0.5 mm or less. Within this range, the shaping property during lamination and the properties such as the mechanical strength and toughness of the cured laminate are fully exhibited, which is suitable.

[0082] [Film] The film of this embodiment contains the cured product of the resin composition of this embodiment. The cured product obtained by curing the resin composition of the present embodiment can be formed into a film and used for various applications. As a method of curing the resin composition of the present embodiment to obtain a cured product and forming it into a film, various known methods are applicable. For example, a method of forming a film made of the resin composition of the present embodiment can be mentioned, in which the varnish described above is applied on a support substrate such as a thermoplastic resin film, dried, and then heat-treated or the like to crosslink the resin composition to obtain a cured product. As the thermoplastic resin film, a PET film, a polyimide resin film, or the like can be used. The method of applying the varnish to the support substrate is not particularly limited, and examples thereof include application using a spin coater, application using a spray coater, and application using a bar coater. In addition, a method of forming a film made of the resin composition of the present embodiment can also be mentioned, in which after melting and molding the resin composition of the present embodiment to obtain a film, the resin composition is crosslinked by heat treatment or the like to obtain a cured product.

[0083] [Laminate] The laminate of the present embodiment includes the film of the present embodiment or the prepreg of the present embodiment. The film or prepreg of the present embodiment can be laminated on a substrate and used for various applications as a laminate. For example, it can also be used as an organic insulating film that requires low dielectric properties or a curable adhesive sheet for a device having an adhesive layer. Various known methods are applicable as the method of forming the laminate of the present embodiment. For example, a laminate can be produced by laminating the film produced by the above-described method on a substrate and heat-curing it by pressing or the like as necessary. In addition, a laminate can also be produced by laminating an electrical insulating layer containing the cured product described above on a conductor layer.

[0084] [Multi-layer molded body or multi-layer laminated film] The cured product obtained by curing the resin composition of the present embodiment may be formed on the surface layer of various multi-layer molded bodies or multi-layer laminated films. Examples of various multilayer molded articles or multilayer laminated films include, for example, a multilayer molded article for an optical lens in which the film of the present embodiment is formed on the surface of a resin optical lens, and a multilayer gas barrier film in which the film of the present embodiment is formed on the surface of a resin film such as a PET film or a PE film for imparting gas barrier properties.

[0085] [Metal-clad laminate] The metal-clad laminate of the present embodiment includes a metal foil on at least one side of the laminate of the present embodiment. The laminate of the present embodiment may be a metal-clad laminate by laminating a metal foil on at least one surface of the laminate of the present embodiment and heat-curing it by a lamination press or the like. Further, the metal foil may be bonded to both surfaces of the laminate. Examples of the metal foil include copper foil, aluminum foil, nickel foil, gold foil, silver foil, stainless steel foil, etc. From the viewpoints of economy, processability, thermal conductivity, and conductivity, electrolytic copper foil is preferably used. Various known methods can be applied to the method for producing the metal-clad laminate of the present embodiment. For example, a metal-clad laminate can be produced by laminating a metal foil on the laminate of the present embodiment and heat-curing it by pressing or the like as necessary.

[0086] Since the metal-clad laminate of the present embodiment uses a cured product obtained by curing the resin composition of the present embodiment, it has an excellent performance balance of low dielectric characteristics, low thermal expansion, and thermal conductivity, which is suitable for a printed wiring board. Therefore, the metal-clad laminate of the present embodiment can be suitably used as a material for the insulating layer of a printed wiring board.

[0087] [Printed wiring board] The printed wiring board of the present embodiment is manufactured using the prepreg of the present embodiment or the metal-clad laminate of the present embodiment. Since the cured product obtained by curing the resin composition of the present embodiment has an excellent performance balance of low dielectric characteristics, low thermal expansion, and thermal conductivity, it can be suitably used for a printed wiring board. As a method for manufacturing a printed wiring board, a generally known method can be adopted and is not particularly limited. For example, the film or laminate manufactured by the aforementioned method is heat-cured by lamination pressing or the like to form an electrical insulation layer. Next, a conductor layer is laminated on the obtained electrical insulation layer by a known method to produce a laminate. Thereafter, a printed wiring board can be obtained by circuit processing or the like of the conductor layer in the laminate.

[0088] As the metal for the conductor layer, for example, copper, aluminum, nickel, gold, silver, stainless steel, etc. can be used. As a method for forming the conductor layer, for example, a method of heat-fusing the above metals in the form of foil or the like onto the electrical insulation layer, a method of bonding the above metals in the form of foil or the like onto the electrical insulation layer using an adhesive, or a method of forming a conductor layer made of the above metals on the electrical insulation layer by sputtering, vapor deposition, plating, or the like can be mentioned. As an aspect of the printed wiring board, either a single-sided board or a double-sided board may be used.

[0089] Such a printed wiring board can be used as an electronic device, for example, by mounting electronic components such as semiconductor elements. In addition, the electronic device of the present embodiment includes the film or printed wiring board of the present embodiment. The electronic device of the present embodiment can be manufactured based on known information. Examples of such electronic devices include ICT infrastructure devices such as servers, routers, supercomputers, mainframes, and workstations; antennas such as GPS antennas, wireless base station antennas, millimeter wave antennas, and RFID antennas; communication devices such as mobile phones, smartphones, PHS, PDAs, and tablet terminals; digital devices such as personal computers, televisions, digital cameras, digital video cameras, POS terminals, wearable terminals, and digital media players; in-vehicle electronic devices such as electronic control system devices, in-vehicle communication devices, car navigation devices, millimeter wave radars, and in-vehicle camera modules; semiconductor test devices, high-frequency measurement devices, etc.; high-speed communication compatible modules; and the like.

[0090] [High-speed communication compatible module] The electronic device of this embodiment includes a high-speed communication compatible module. The high-speed communication compatible module of this embodiment is a high-speed communication compatible module manufactured using the film or printed wiring board of this embodiment. The high-speed communication compatible module of this embodiment is, for example, a communication module formed by mounting a semiconductor chip or the like on the printed wiring board of this embodiment, and particularly uses signals in the high-frequency range such as wireless communication devices and network infrastructure devices, and is suitable for applications with large information communication volume and high speed.

[0091] [Applications of the cured product] Since the cured product obtained by curing the resin composition of this embodiment has a good performance balance of low dielectric characteristics, low thermal expansion, and thermal conductivity, for example, optical fibers, optical waveguides, optical disk substrates, optical filters, lenses, optical adhesives, optical filters for PDPs, coating materials for organic ELs, base film substrates for solar cells in the aerospace field, coating materials for solar cells and thermal control systems, electronic elements such as semiconductor elements, light-emitting diodes, various memories, hybrid ICs, MCMs, printed wiring boards, prepregs and laminates used to form the insulating layer of printed wiring boards, overcoat materials or interlayer insulating materials for display components, substrates for liquid crystal displays and solar cells, medical instruments, automotive members, resin modifiers, transparent substrates for displays, gas barrier coating materials, wire covering materials, automotive members, aerospace members, process materials for semiconductors, wire coating materials, members for lithium ion batteries, members for fuel cells, capacitor films, flexible display members, anchor coating materials, transparent adhesives, and hard coating materials. In particular, the cured product obtained by curing the resin composition of this embodiment has an improved performance balance of low dielectric characteristics, low thermal expansion, and thermal conductivity, and also has a good performance balance of insulation and mechanical properties, etc., so it can be suitably used for circuit boards, and can be more suitably used for high-frequency applications such as high-frequency circuit boards.

[0092] As described above, the embodiments of the present invention have been described, but these are examples of the present invention, and various configurations other than the above can also be adopted. In addition, the present invention is not limited to the above-described embodiments, and modifications, improvements, etc. within the scope that do not impair the effects of the present invention are included in the present invention.

Example

[0093] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereby.

[0094] The following raw materials were used in the experiment.

[0095] (Raw materials) · Thermosetting cyclic olefin copolymer (A): The synthesis method will be described later. · Radical polymerization initiator (B) 1: 2,3 - dimethyl - 2,3 - diphenylbutane (manufactured by Thermo Fisher Scientific) · Radical polymerization initiator 2: Dicumyl peroxide (manufactured by NOF Corporation) · Stabilizer: Phenolic antioxidant (pentaerythritol - tetrakis [3 - (3',5' - di - tert - butyl - 4' - hydroxyphenyl) propionate]) (manufactured by BASF) · Cross - linking agent (C) 1 having a benzocyclobutene structure: 4 - vinylbenzocyclobutene (manufactured by Merck) · Cross - linking agent having no benzocyclobutene structure: Bismuthiol (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0096] The following raw materials were used for the synthesis of the thermosetting cyclic olefin copolymer. Transition metal compound (1): Synthesized by the method described in Synthesis Example 1 of JP - A - 2004 - 331965.

[0097]

Chemical formula

[0098] The following raw materials were used for the synthesis. · Modified methylaluminoxane (MMAO, manufactured by Tosoh Finechem Corporation) · Toluene (manufactured by Wako Pure Chemical Industries, Ltd.: Wako Special Grade) · Tetracyclo[4.4.0.1 2,5 .1 7,10 -3-dodecene (hereinafter also referred to as TD) (manufactured by Mitsui Chemicals, Inc.) · 5-Vinyl-2-norbornene (hereinafter also referred to as VNB) (manufactured by Tokyo Chemical Industry Co., Ltd.) · Acetone (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.: Wako Special Grade) · Methanol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.: Wako Special Grade)

[0099] [Method for Measuring Content of Each Repeating Unit Constituting Cyclic Olefin Copolymer] The contents of repeating unit (a), repeating unit (b), and repeating unit (c) were measured under the following conditions using a nuclear magnetic resonance apparatus "EXcalibur270" manufactured by JEOL Ltd. Number of integrations: 16 to 64 times Measurement temperature: room temperature From the 1 1H-NMR spectrum obtained by the above measurement, the contents of repeating unit (a), repeating unit (b), and repeating unit (c) were calculated respectively based on the intensities of the peaks derived from the hydrogen directly bonded to the double bond carbon and the peaks of the other hydrogens.

[0100] [Method for Measuring Residual Amount of Peroxide-Based Polymerization Initiator] The residual amount of the peroxide-based polymerization initiator in the thermosetting film prepared with a thickness of about 70 μm was measured under the following conditions using a GC-MS apparatus "HP7890B-HP5977B" manufactured by Agilent Technologies and a thermal desorption apparatus "MPS / TDU / CIS4" manufactured by GERSTEL. Heating extraction temperature: 230 °C × 20 minutes Heating extraction flow rate: 100 ml / min Trap temperature: -150 °C Desorption temperature: 300 °C × 2 minutes Column: "HP-5MS" Column flow rate: 2.0 mL / min Temperature rising condition: 40 °C (3 min) - 20 °C / min - 320 °C (23 min) Injection range: m / z 15 - 700 Among the peaks obtained in the above measurement, the components detected after a retention time of 10 minutes were quantified in terms of toluene conversion, and all the quantified values were integrated to obtain the residue amount derived from the peroxide initiator.

[0101] [Number average molecular weight (Mn)] Using gel permeation chromatography (GPC), the number average molecular weight (Mn) of the polymer dissolved in o-dichlorobenzene-d4 was measured under the following conditions by calibrating the molecular weight with a monodisperse polystyrene standard (manufactured by Tosoh Corporation). Measuring device: Gel permeation chromatograph HLC-8321 GPC / HT type manufactured by Tosoh Corporation Data processing software: Empower3 manufactured by Waters Detector: Brice type double-pass, dual-flow type RI detector (built-in type) manufactured by Tosoh Corporation Column: TSKgel GMH6-HT, TSKgel GMH6-HTL manufactured by Tosoh Corporation Column temperature: 140 °C Sample concentration: 0.1% (w / v) Injection volume: 400 μL Sampling interval: 0.5 seconds Flow rate: 1.0 ml / min

[0102] Thermosetting cyclic olefin copolymer: [Synthesis Example 1: Thermosetting cyclic olefin copolymer (A)] Into a 1 L SUS autoclave with sufficient nitrogen substitution, 455 ml of toluene, 29 ml of VNB, 16 ml of TD, a hexane solution of MMAO with 0.8 mmol in terms of aluminum atom, and 446 ml of hydrogen were charged. Then, ethylene was introduced into the system until the total pressure reached 0.6 MPa. A toluene solution of 0.028 mmol of the transition metal compound (1) was added, and polymerization was carried out at 35 °C for 50 minutes. Thereafter, the polymerization was stopped by injecting 1 ml of methanol. After the completion of the coincidence, ion-exchanged water was added to the obtained polymer solution, and the mixture was stirred for 1 hour. Then, the organic layer was filtered through filter paper. This organic layer was poured into a mixed solvent of acetone and methanol to precipitate the polymer, and after stirring, it was filtered through filter paper. The obtained polymer was dried under reduced pressure at 80 °C for 10 hours to obtain an ethylene / TD / VNB copolymer, which is a thermosetting cyclic olefin-based copolymer (A). 1 The content of the repeating unit (c) derived from TD in the copolymer (A) determined by 1H-NMR was 11 mol%, the content of the repeating unit (b) derived from VNB was 26 mol%, and the number average molecular weight (Mn) determined by GPC measurement was 25,000.

[0103] [Example 1] (Preparation of varnish) The thermosetting cyclic olefin-based copolymer (A) obtained in Synthesis Example 1 was weighed according to the composition shown in Table 1 using toluene as a solvent. The weighed sample was stirred until it was completely dissolved to obtain a varnish containing the target cyclic olefin-based copolymer composition. The unit of the blending ratio of each raw material in Table 1 is parts by mass.

[0104] (Preparation of cured film) The obtained varnish was coated on a release-treated PET film at a speed of 10 mm / second, and then dried in a hot air dryer at 150 °C for 4 minutes under a nitrogen stream. Two obtained films were stacked and vacuum pressing was performed. Specifically, the following steps were performed under a vacuum controlled to 20 kPa or less. In the case of radical polymerization initiator 1, the temperature was raised from room temperature (25 °C) at a constant rate, the press pressure was applied to 3.5 MPa, and then it was held at 180 °C for 60 minutes. After cooling to room temperature, it was peeled off from the PET film, sandwiched again with a polyimide film, the press pressure was applied to 3.5 MPa between the polyimide films, and then held at 220 °C for 120 minutes to obtain a thermoset film. In the case of radical polymerization initiator 2, the temperature was raised from room temperature (25 °C) at a constant rate, the press pressure was applied to 3.5 MPa, and then it was held at 180 °C for 120 minutes to obtain a thermoset film. The obtained thermosetting film was evaluated for dielectric measurement and thermal expansion measurement based on the following procedure. The obtained results are shown in Table 1. The film thickness was adjusted to 20 - 70 μm in each case.

[0105] (Evaluation of the cured film) · Dielectric tangent evaluation: For the thermosetting films obtained in the examples and comparative examples, the dielectric tangent Df was evaluated according to the following procedure. In this evaluation, a dielectric tangent of 0.00100 or less was defined as a physical property value indicating suitable low dielectric characteristics. (Evaluation procedure) The thermosetting film of each example was cut into test pieces with a length of 50 mm, a width of 50 mm, and a thickness of 50 μm. Then, for the obtained test pieces, the dielectric tangent Df at 23 ± 2 °C, 50 ± 5% RH, and 10 GHz was measured by the cylindrical cavity resonator method using a cylindrical cavity resonator (manufactured by YHP, Synthesized Sweeper 8340B and Network Analyzer 8510B manufactured by YHP).

[0106] · Linear expansion measurement: For the thermosetting films obtained in the examples and comparative examples, the linear expansion coefficient (CTE) in the ranges of 25 - 90 °C (1 st run) and 160 - 280 °C (2 nd run) was evaluated according to the following procedure. In this evaluation, a CTE of less than 80 ppm / K for the former and a CTE of less than 140 ppm / K for the latter were defined as characteristic values indicating suitable thermal expansion characteristics. Also, the dimensional change reduction rate with respect to the actual dimensional change in the temperature range from - 30 °C to 300 °C was defined as the "thermal expansion reduction rate", calculated based on Comparative Example 2, and a reduction rate of 5% or more was evaluated as excellent low thermal expansibility. Thermal expansion reduction rate = {(Actual dimensional change of Comparative Example 2) - (Actual dimensional change of each evaluation sample)} / (Actual dimensional change of Comparative Example 2) × 100 (Evaluation procedure) The thermosetting film was cut into test pieces with a length of 20 mm, a width of 4 mm, and a thickness of about 50 μm. Next, for the obtained test pieces, using a thermomechanical analyzer (TMA7100C manufactured by Hitachi High-Tech Corporation), the measurement temperature range was -30 to 300 °C, the heating rate was 5 °C / min, the test load was 5 kgf, and the measurement was carried out under a nitrogen atmosphere under the condition of film elongation mode. From this measurement result, the coefficient of thermal expansion CTE in each of the temperature ranges of 25 to 90 °C and 160 to 280 °C was calculated.

[0107] [Examples 2 and Comparative Examples 1 to 4] Varnish and thermosetting film were respectively produced and evaluated in the same manner as in Example 1 except that the composition according to the formulation shown in Table 1 was used. The obtained results are shown in Table 1.

[0108]

Table 1

Claims

1. A thermosetting cyclic olefin copolymer (A) having a functional group (α) that can be used in a crosslinking reaction, Radical polymerization initiator (B), A crosslinking agent (C) having a benzocyclobutene structure, A resin composition containing, A resin composition in which the content of a peroxide-based polymerization initiator is less than 50 parts by mass per 100 parts by mass of the radical polymerization initiator (B).

2. The copolymer (A) is One or more repeating units (a) derived from olefins represented by the following formula (I), A repeating unit (b) derived from one or more cyclic non-conjugated dienes represented by the following formula (III), A repeating unit (c) derived from one or more cyclic olefins represented by the following formula (V), The resin composition according to claim 1, comprising: 【Chemistry 1】 (In the above formula (I), R ３００ (This indicates a hydrogen atom or a linear or branched hydrocarbon group having 1 to 29 carbon atoms.) 【Chemistry 2】 (In the above formula (III), u is 0 or 1, v is 0 or a positive integer, w is 0 or 1, R ６１ ~R ７６ And R ａ１ and R ｂ１ These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, R １０４ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, t is a positive integer from 0 to 10, and R ７５ and R ７６ (These may be bonded to each other to form a monocycle or polycycle.) 【Transformation 3】 (In the above formula (V), u is 0 or 1, v is 0 or a positive integer, w is 0 or 1, and R ６１ ~R ７８ as well as R ａ１ and R ｂ１ may be the same as or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, and R ７５ ~R ７８ may be bonded to each other to form a monocyclic or polycyclic ring)

3. The resin composition according to claim 1, wherein when a cured product of the resin composition with a thickness of 50 μm is prepared, the dielectric loss tangent Df of the cured product at a frequency of 10 GHz is 0.00100 or less.

4. A varnish comprising the resin composition according to claim 1 and a solvent.

5. A prepreg obtained by impregnating a fibrous substrate with the resin composition described in claim 1 or the varnish described in claim 4.

6. A thermosetting cyclic olefin copolymer (A) having a functional group (α) that can be used in a crosslinking reaction, Radical polymerization initiator (B), A crosslinking agent (C) having a benzocyclobutene structure, A cured product of a resin composition containing, A cured product having a residue amount of less than 0.3% by mass derived from peroxide-based polymerization initiators.

7. A film comprising a cured product of the resin composition according to claim 1 or a cured product according to claim 6.

8. A laminate comprising the prepreg described in claim 5.

9. A laminate comprising the film described in Claim 7.

10. A metal-clad laminate comprising a metal foil on at least one side of the laminate according to claim 8.

11. A printed circuit board manufactured using the metal-clad laminate described in claim 10.

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