Resin composition, resin film, prepreg and metal-clad laminate

Abstract

To provide a resin composition which comprises a polyphenylene ether having excellent solvent solubility and has excellent electrical properties, copper foil peeling strength and solvent resistance.SOLUTION: There is provided a resin composition which comprises (A) a polyphenylene ether A containing a repeating unit derived from the following phenol and having a molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) of 2.0 to 6.0 and a number of OH groups per molecule of 0.8 to 3.0 pieces / molecule, (B) a polyphenylene ether B containing a repeating unit derived from the following phenol and at least one partial structure of the following structures in the molecular skeleton (excluding those corresponding to the polyphenylene ether A), (C) a triallyl isocyanurate and / or a triallyl cyanurate and a crosslinking agent other than (C') a triallyl isocyanurate and a triallyl cyanurate as optional components and (D) an organic peroxide.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resin composition, a resin film, a prepreg, and a metal-clad laminate.

Background Art

[0002] Polyphenylene ether (hereinafter also referred to as "PPE") has excellent high-frequency characteristics, flame retardancy, and heat resistance, and thus is widely used as a material for products and parts in the fields of electric and electronic, automotive, food and packaging, and other various industrial material fields. In particular, in recent years, taking advantage of its low dielectric characteristics and heat resistance, its application as a modifier in various applications including electrical and electronic applications such as substrate materials has been promoted.

[0003] However, generally, high-molecular-weight polyphenylene ether having repeating units derived from monohydric phenols typified by 2,6-dimethylphenol dissolves in a very highly toxic solvent such as chloroform, but is hardly soluble in aromatic solvents such as toluene known as good solvents even at high concentrations at room temperature, and is insoluble in ketone solvents such as methyl ethyl ketone. Therefore, for example, when used as a wiring board material, it is difficult to handle with a resin varnish solution such as toluene or methyl ethyl ketone.

[0004] Patent Document 1 discloses a resin composition in which a varnish is prepared by heating and melting polyphenylene ether in an aromatic solvent in order to improve the solubility and dispersibility of polyphenylene ether. However, in this method, there is a concern about the volatilization of the organic solvent, and temperature adjustment is also required during varnish coating. Further, Patent Document 2 discloses a resin composition obtained by redistributing a high-molecular polyphenylene ether and a monofunctional or polyfunctional phenol, and terminally modifying a low-molecular polyphenylene ether component, and containing a high-molecular polyphenylene ether, a crosslinking agent, and an organic peroxide. Patent Document 3 discloses a resin composition containing two types of terminally modified low-molecular polyphenylene ethers having different skeletons and a crosslinking type curing agent.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, even when using a resin composition as described in Patent Document 1, a resin composition containing polyphenylene ether that is soluble in toluene at room temperature (has solvent solubility) cannot be obtained, and the copper foil peel strength and toluene resistance of the cured resin composition also have further problems. In addition, polyphenylene ether obtained by a redistribution reaction as disclosed in Patent Document 2 generally contains an organic peroxide used in the redistribution reaction, and the organic peroxide remaining in the product may adversely affect the dielectric properties of the substrate. Even in the resin composition as disclosed in Patent Document 3, compared with a resin composition using each terminal-modified low-molecular-weight polyphenylene ether alone, it is merely a trade-off relationship, and no improvement in dielectric properties, copper foil peel strength, etc. has been observed by using two types of terminal-modified low-molecular-weight polyphenylene ethers in combination.

[0007] The present invention has been made in view of the above problems, and an object thereof is to provide a resin composition excellent in electrical properties, copper foil peel strength, and solvent resistance even when using polyphenylene ether excellent in solvent solubility. Another object of the present invention is to provide a resin film, prepreg, and metal-clad laminate formed using the resin composition.

Means for Solving the Problems

[0008] That is, the present invention is as follows. [1] (A) It contains a repeating unit derived from the phenol of the following formula (1) and a repeating unit derived from the phenol of the following formula (2), The molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is 2.0 to 6.0, The polyphenylene ether A having 0.8 to 3.0 OH groups per molecule. (B) A polyphenylene ether B containing a repeating unit derived from the phenol of the following formula (1) and having at least one partial structure selected from the group consisting of the following formulas (4), (5), (6), and (7) in the molecular skeleton (however, excluding those corresponding to the above polyphenylene ether A), (C) Triallyl isocyanurate and / or triallyl cyanurate, (C’) A crosslinking agent other than triallyl isocyanurate and triallyl cyanurate as an optional component, and (D) A resin composition characterized by containing an organic peroxide. [Chemical formula] (In formula (1), R 11 is each independently an optionally substituted saturated hydrocarbon group having 1 to 6 carbon atoms, an optionally substituted aryl group having 6 to 12 carbon atoms, or a halogen atom, and R 12 is each independently a hydrogen atom, an optionally substituted hydrocarbon group having 1 to 6 carbon atoms, an optionally substituted aryl group having 6 to 12 carbon atoms, or a halogen atom.) [Chemical formula] (In formula (2), R 22 is each independently a hydrogen atom, an optionally substituted saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, an optionally substituted aryl group having 6 to 12 carbon atoms, or a halogen atom, and two R 22 are not both hydrogen atoms, and R21 is a partial structure represented by the following formula (3).

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Advantages of the Invention

[0009] According to the present invention, a polyphenylene ether resin composition excellent in electrical properties, copper foil peel strength, and solvent resistance can be provided. Further, according to the present invention, an electronic circuit board material, a resin film, a prepreg, and a metal-clad laminate formed using the polyphenylene ether resin composition can be provided.

Mode for Carrying Out the Invention

[0010] Hereinafter, a mode for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described in detail. The following present embodiment is an exemplification for explaining the present invention, and the present invention is not limited only to this present embodiment, and the present invention can be appropriately modified and implemented within the scope of its gist.

[0011] In the present embodiment, when a polyphenylene ether in which some or all of the hydroxyl groups contained in the polyphenylene ether are modified is simply expressed as "polyphenylene ether", it may include both unmodified polyphenylene ether and modified polyphenylene ether as long as there is no particular contradiction.

[0012] In this specification, A (numerical value) to B (numerical value) means A or more and B or less. In this specification, the substituent refers to, for example, a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a halogen atom, and the like.

[0013] <Resin Composition> The resin composition of the present embodiment is a resin composition containing (A) polyphenylene ether A, (B) polyphenylene ether B, (C) triallyl isocyanurate and / or triallyl cyanurate, (C') a crosslinking agent other than triallyl isocyanurate and triallyl cyanurate as an optional component, and (D) an organic peroxide.

[0014] (Polyphenylene Ether A) The polyphenylene ether A contains at least a repeating unit derived from the phenol of the following formula (1) and a repeating unit derived from the phenol of the following formula (2), and may consist only of the repeating unit derived from the phenol of the following formula (1) and the repeating unit derived from the phenol of the following formula (2). Further, the number of OH groups per molecule is 0.8 to 2.5 per molecule.

Chemical formula

Chemical formula

Chemical formula

[0015] In the above formula (1), R 11 is preferably, independently of one another, a saturated hydrocarbon group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms, more preferably a methyl group or a phenyl group, and even more preferably a methyl group. In formula (1), it is preferable that the two R 11 have the same structure.

[0016] In the above formula (1), R 12 is preferably, independently of one another, a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, more preferably a hydrogen atom or a methyl group. In formula (1), it is preferable that the two R 12 are different, and it is more preferable that one is a hydrogen atom and the other is a hydrocarbon group having 1 to 6 carbon atoms (preferably a methyl group).

[0017] In the above formula (2), R 22 is preferably, independently of one another, a hydrogen atom, a saturated or unsaturated hydrocarbon group having 1 to 15 carbon atoms, or an aryl group having 6 to 12 carbon atoms which may be substituted by an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms which may be substituted by an alkyl group having 1 to 6 carbon atoms, and even more preferably a hydrogen atom or a methyl group. In formula (2), it is preferable that the two R 22 are different, and it is more preferable that one is a hydrogen atom and the other is a hydrocarbon group having 1 to 6 carbon atoms (preferably a methyl group).

[0018] The partial structure represented by the above formula (3) is preferably a group containing a secondary and / or tertiary carbon, and examples thereof include an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a tert-amyl group, a 2,2-dimethylpropyl group, a cyclohexyl group, and a structure having a phenyl group at the end thereof, etc. More preferably, it is a tert-butyl group or a cyclohexyl group, and even more preferably a tert-butyl group.

[0019] Since the phenol of formula (1) has no unsubstituted ortho position (i.e., since hydrogen atoms are not bonded to the two carbon atoms in the ortho positions of the carbon atom to which the hydroxyl group is bonded), it can react with another phenolic monomer only at the phenolic hydroxyl group and the para - position carbon atom. Therefore, the repeating unit derived from formula (1) includes a repeating unit having the structure of the following formula (9). [Chemical formula] (In formula (9), R 11 and R 12 are the same as in formula (1).)

[0020] The phenol of formula (2) can react with another phenolic monomer at either the ortho - position or the para - position of the phenol in addition to the phenolic hydroxyl group. Therefore, the repeating unit derived from the phenol of formula (2) has the structure of the following formula (10), the structure of the following formula (11) or a combination thereof. [Chemical formula] (R 21 , R 22 in formula (10) and formula (11) are the same as in formula (2).)

[0021] By including the repeating unit derived from the phenol of the above formula (1) and the repeating unit derived from the phenol of the above formula (2), the polyphenylene ether A has excellent solvent solubility, and in addition, the electrical properties, copper foil peel strength and toluene resistance of the resin composition and its cured product are improved.

[0022] Also, the polyphenylene ether A has a molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) of 2.0 to 6.0, preferably 2.5 to 5.5 or less, and more preferably 3.0 to 5.0. When the molecular weight distribution (Mw / Mn) determined by gel permeation chromatography (GPC) is 2.0 or more, the fluidity of the polyphenylene ether is improved, and the reactivity during thermosetting is enhanced. When the molecular weight distribution (Mw / Mn) is 6.0 or less, the toughness of the polyphenylene ether is improved, and excellent copper foil peel strength and solvent resistance of the cured product can be obtained.

[0023] As means for making the molecular weight distribution of the polyphenylene ether A fall within the above range, adjustment of the polymerization temperature, adjustment of the catalyst equivalent, adjustment of the monomer concentration in the reaction system, etc. can be mentioned from the viewpoint of controlling the polymerization reactivity. Among these, as a method for adjusting the monomer concentration in the reaction system, a method of gradually adding the monomer to the reaction system is preferable. When the monomer concentration in the reaction system is high from the beginning, it is difficult to control the molecular weight of the polymer produced because the reaction rate between the monomers is high. On the other hand, by the method of adding the monomer to the reaction system at an appropriate flow rate, the monomer concentration in the reaction system can be controlled, and the reaction rate can be easily controlled. As a result, a polymer having a molecular weight distribution in a preferable range can be obtained.

[0024] The polyphenylene ether A has 0.8 to 3.0 OH groups per molecule, preferably 1.0 to 2.8 OH groups per molecule, and more preferably 1.0 to 2.5 OH groups per molecule. When the number of OH groups per molecule is 0.8 or more per molecule, the copper foil peel strength is improved, and when it is 3.0 or less per molecule, the heat resistance and dielectric properties of the substrate are improved, and the production stability of the polyphenylene ether can be ensured.

[0025] The polyphenylene ether A preferably contains a repeating unit derived from the phenol of the above formula (1) in an amount of 55 mol% or more and less than 90 mol%, and a repeating unit derived from the phenol of the above formula (2) in an amount of more than 10 mol% and 45 mol% or less, and more preferably contains a repeating unit derived from the phenol of the above formula (1) in an amount of 60 mol% or more and less than 85 mol%, and a repeating unit derived from the phenol of the above formula (2) in an amount of more than 15 mol% and 40 mol% or less. By including the repeating unit derived from the phenol of the above formula (1) and the repeating unit derived from the phenol of the above formula (2) in the above ratio, in addition to the polyphenylene ether having excellent solvent solubility, the electrical properties, heat resistance, and solvent resistance of the resin composition and its cured product tend to be improved.

[0026] The polyphenylene ether A preferably has a reduced viscosity (ηsp / c) measured in a chloroform solution with a concentration of 0.5 g / dL at 30°C in the range of 0.13 to 0.30 dL / g, more preferably in the range of 0.15 to 0.28 dL / g, and even more preferably in the range of 0.17 to 0.25 dL / g. When the reduced viscosity (ηsp / c) measured in a chloroform solution with a concentration of 0.5 g / dL at 30°C is 0.13 dL / g or more, there is a tendency to obtain high heat resistance and excellent dielectric properties derived from the polyphenylene ether structure. When it is 0.30 dL / g or less, there is a tendency to ensure solubility in solvents such as toluene and methyl ethyl ketone. The reduced viscosity can be measured by the method described in the examples below.

[0027] (Polyphenylene ether B) The polyphenylene ether B contains a repeating unit derived from the phenol of the above formula (1) and has at least one partial structure selected from the group consisting of the following formulas (4), (5), (6), and (7) in its molecular skeleton. [Chemical formula] (In the above formula (6), R 6 is a hydrogen atom or a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms, and the saturated or unsaturated hydrocarbon may have substituents to the extent that it satisfies the condition of having 1 to 10 carbon atoms. In the above formula (7), R 7 is a saturated or unsaturated divalent hydrocarbon group having 1 to 10 carbon atoms, the saturated or unsaturated divalent hydrocarbon may have substituents to the extent that it satisfies the condition of having 1 to 10 carbon atoms, and R8 is a hydrogen atom or a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms, and the saturated or unsaturated hydrocarbon may have a substituent to the extent that it satisfies the condition of having 1 to 10 carbon atoms.) In addition, the partial structure represented by at least one selected from the group consisting of the above formula (5), formula (6), formula (7), and formula (8) may be directly bonded to the oxygen of the hydroxyl group contained in the polyphenylene ether B.)

[0028] Further, the polyphenylene ether B may further contain a structural unit derived from the phenol of the following formula (8). [Chemical formula] (In the above formula (8), X is an a-valent arbitrary linking group, a is an integer of 2 to 6, R 9 is either a linear alkyl group having 1 to 8 carbon atoms or the partial structure represented by the above formula (3), and with the carbon atom of the benzene ring to which -O- is bonded being the 1-position, it is bonded to at least one of the carbon atoms at the 2-position or 6-position, and k is each independently an integer of 1 to 4.)

[0029] In the above formula (8), R 9 is each independently either a linear alkyl group having 1 to 8 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, or the partial structure represented by the above formula (3), and it is preferably a methyl group or the structure of the above formula (3). The a partial structures may be the same structure or different structures. Among them, from the viewpoint of achieving a polyphenylene ether with even better solubility in a solvent and an even higher glass transition temperature after curing, it is preferable that the a partial structures have the same structure.)

[0030] In the above formula (8), k is an integer of 1 to 4, preferably an integer of 2 to 4.)

[0031] Also, in the above formula (8), R 9 is bonded to at least one of the carbon atoms at the 2-position and 6-position with the carbon atom of the benzene ring to which -O- is bonded being the 1-position, and R 9When it is a linear alkyl group having 1 to 8 carbon atoms, it is preferably bonded to both the 2-position and the 6-position, and R bonded to the 2-position and / or 6-position 9 When it is a partial structure represented by the formula (3), it is preferably bonded to only one of the 2-position or the 6-position.

[0032] R in the above formula (2) 21 and R in the above formula (8) 9 When both are partial structures (functional groups) represented by the formula (3) (when the partial structure (functional group) represented by the formula (3) is substituted in both the phenol compound represented by the above formula (2) and the phenol compound represented by the above formula (8)), the structures of the partial structures (functional groups) represented by the respective formulas (3) may be the same or different.

[0033] In the above formula (8), X is an a-valent arbitrary linking group and is not particularly limited. For example, hydrocarbon groups such as chain hydrocarbons and cyclic hydrocarbons; hydrocarbon groups containing one or more atoms selected from nitrogen, phosphorus, silicon, and oxygen; atoms such as nitrogen, phosphorus, and silicon; or groups combining these, etc. may be mentioned. X may be a linking group excluding a single bond. X may be a linking group that links a partial structures to each other.

[0034] Incidentally, as the X, an a-valent alkyl skeleton bonded to the benzene ring to which R 9 is bonded, a single bond, an a-valent aryl skeleton bonded to the benzene ring to which R 9 is bonded, through an ester bond or the like, and an a-valent heterocyclic skeleton bonded to the benzene ring to which R 9 is bonded, through a single bond or an ester bond or the like, may be mentioned. Here, the alkyl skeleton is not particularly limited. For example, a branched terminal of a chain hydrocarbon having at least a carbon number of 2 to 6 and branched at least a times (for example, a chain saturated hydrocarbon), etc., in which the branched terminal is directly bonded to the benzene ring of the partial structure (it is sufficient that the benzene ring is bonded to a branched terminals, and there may be a branched terminal to which the benzene ring is not bonded). Further, the aryl skeleton is not particularly limited. For example, a benzene ring, a mesitylene group, or a 2-hydroxy-5-methyl-1,3-phenylene group is bonded to the benzene ring to which R 9 is bonded through a single bond or an alkyl chain, etc. Further, the heterocyclic skeleton is not particularly limited. For example, a triazine ring is bonded to the benzene ring to which R 9 is bonded through a single bond or an alkyl chain, etc.

[0035] In the above formula (8), a is an integer of 2 to 6, preferably an integer of 2 to 4.

[0036] Also, when the phenol of the above formula (8) does not have an unsubstituted ortho position, the structural unit derived from the phenol of the formula (8) has the structure of the following formula (12). When the phenol of the formula (8) has an unsubstituted ortho position, the structural unit derived from the phenol of the formula (8) has the structure of the following formula (12), the structure of the following formula (13), or a combination thereof.

Chemical formula

[0037] Furthermore, the polyphenylene ether B may further contain a repeating unit derived from the phenol of the above formula (2). However, the polyphenylene ether B excludes those corresponding to the polyphenylene ether A.

[0038] Further, the polyphenylene ether B preferably has a number average molecular weight of 1,000 or more and 30,000 or less, more preferably 1,500 or more and 25,000 or less, and still more preferably 1,500 or more and 20,000 or less. When the number average molecular weight of the polyphenylene ether B is 1,000 or more, toughness can be imparted to the resin composition and its cured product, and the copper foil peeling strength can be improved. Further, when the number average molecular weight of the polyphenylene ether B is 30,000 or less, the viscosity of the varnish can be reduced in the step of mixing the resin composition with a solvent, improving the handleability, and further reducing the melt viscosity of the resin composition in the thermosetting step to improve the crosslinking reaction rate. The number average molecular weight of the polyphenylene ether B is preferably a value measured by a general molecular weight measurement method. Specifically, examples include values measured using GPC.

[0039] In this embodiment, the structure of the polyphenylene ether can be identified by analyzing it using techniques such as NMR and mass spectrometry. As a specific method for identifying the structure of the polyphenylene ether, it is known that field desorption mass spectrometry (FD-MS), which is less likely to cause fragmentation, is performed, and the repeating unit can be estimated based on the interval between the detected ions. Further, a method for estimating the structure of the polyphenylene ether by combining peak analysis of fragment ions by electron ionization method (EI) and structure analysis by NMR can be mentioned.

[0040] (Method for producing polyphenylene ether) The polyphenylene ethers A and B can be obtained, for example, by a method including at least a step of subjecting a monohydric phenol compound represented by the above formula (1) or (2), or a monohydric or polyhydric phenol compound represented by the above formula (1) or (8) to oxidative polymerization. In the step of performing the oxidative polymerization, it is preferable to subject a raw material containing at least the phenol of the above formula (1) and the phenol of the above formula (2), or the phenol of the above formula (1) and the phenol of the above formula (8) to oxidative polymerization.

[0041] Examples of the monohydric phenol compound represented by the above formula (1) include 2,6-dimethylphenol, 2-methyl-6-ethylphenol, 2,6-diethylphenol, 2-ethyl-6-n-propylphenol, 2-methyl-6-chlorophenol, 2-methyl-6-bromophenol, 2-methyl-6-n-propylphenol, 2-ethyl-6-bromophenol, 2-methyl-6-n-butylphenol, 2,6-di-n-propylphenol, 2-ethyl-6-chlorophenol, 2-methyl-6-phenylphenol, 2,6-diphenylphenol, 2-methyl-6-tolylphenol, 2,6-ditolylphenol, 2,3,6-trimethylphenol, 2,3-diethyl-6-n-propylphenol, 2,3,6-tributylphenol, 2,6-di-n-butyl-3-methylphenol, 2,6-dimethyl-3-n-butylphenol, 2,6-dimethyl-3-t-butylphenol, and the like. Among them, 2,6-dimethylphenol, 2,3,6-trimethylphenol, and 2,6-diphenylphenol are particularly preferred because they are inexpensive and easily available. The monohydric phenol compound represented by the above formula (1) may be used alone or in combination of two or more.

[0042] Examples of the monohydric phenol compound represented by the above formula (2) include 2-isopropyl-5-methylphenol, 2-cyclohexyl-5-methylphenol, 2-tert-butyl-5-methylphenol, 2-isobutyl-5-methylphenol, and the like. 2-t-butyl-5-methylphenol and 2-cyclohexyl-5-methylphenol, which are bulky substituents, are more preferred from the viewpoints of suppressing disproportionation and gelation. The monohydric phenol compound represented by the above formula (2) may be used alone or in combination of two or more.

[0043] Among the polyvalent phenol compounds represented by the above formula (8), examples of the phenol compound having two phenol units in the molecule include 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 4,4'-methylenebis(2,6-dimethylphenol), bis(4-hydroxy-3-methylphenyl)sulfide, bis(4-hydroxy-3,5-dimethylphenyl)sulfone, α,α'-bis(4-hydroxy-3,5-dimethylphenyl)-1,4-diisopropylbenzene, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane, 1,1-bis(2-methyl-4-hydroxy-5-t-butylphenyl)butane, and the like. Among them, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane and 1,1-bis(2-methyl-4-hydroxy-5-t-butylphenyl)butane are preferred because they are particularly inexpensive and easily available.

[0044] Furthermore, among the polyvalent phenol compounds represented by the above formula (8), examples of the phenol compounds having three or more phenol units in the molecule include 4,4'-[(3-hydroxyphenyl)methylene]bis(2,6-dimethylphenol), 4,4'-[(3-hydroxyphenyl)methylene]bis(2,3,6-trimethylphenol), 4,4'-[(4-hydroxyphenyl)methylene]bis(2,6-dimethylphenol), 4,4'-[(4-hydroxyphenyl)methylene]bis(2,3,6-trimethylphenol), 4,4'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(2,6-dimethylphenol), 4,4'-[(4-hydroxy-3-ethoxyphenyl)methylene]bis(2,3,6-trimethylethylphenol), 4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2,6-dimethylphenol), 4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2,3,6-trimethylphenol), 2,2'-[(4-hydroxyphenyl)methylene]bis(3,5,6-trimethylphenol), 4,4'-[4-(4-hydroxyphenyl)cyclohexylidene]bis(2,6-dimethylphenol), 4,4'-[(2-hydroxyphenyl)methylene]-bis(2,3,6-trimethylphenol), 4,4'-[1-[4-[1-(4-hydroxy-3,5-dimethylphenyl)-1-methylethyl]phenyl]ethylidene]bis(2,6-dimethylphenol), 4,4'-[1-[4-[1-(4-hydroxy-3-fluorophenyl)-1-methylethyl]phenyl]ethylidene]bis(2,6-dimethylphenol), 2,6-bis[(4-hydroxy-3,5-dimethylphenyl)ethyl]-4-methylphenol, 2,6-bis[(4-hydroxy-2,3,6-trimethylphenyl)methyl]-4-methylphenol, 2,6-bis[(4-hydroxy-3,5,6-trimethylphenyl)methyl]-4-ethylphenol, 2,4-bis[(4-hydroxy-3-methylphenyl)methyl]-6-methylphenol, 2,6-bis[(4-hydroxy-3-methylphenyl)methyl]-4-methylphenol, 2,4-bis[(4-hydroxy-3-cyclohexylphenyl)methyl]-6-methylphenol, 2,4-Bis[(4-hydroxy-3-methylphenyl)methyl]-6-cyclohexylphenol, 2,4-bis[(2-hydroxy-5-methylphenyl)methyl]-6-cyclohexylphenol, 2,4-bis[(4-hydroxy-2,3,6-trimethylphenyl)methyl]-6-cyclohexylphenol, 3,6-bis[(4-hydroxy-3,5-dimethylphenyl)methyl]-1,2-benzenediol, 4,6-bis[(4-hydroxy-3,5-dimethylphenyl)methyl]-1,3-benzenediol, 2,4,6-tris[(4-hydroxy-3,5-dimethylphenyl)methyl]-1,3-benzenediol, 2,4,6-tris[(2-hydroxy-3,5-dimethylphenyl)methyl]-1,3-benzenediol, 2,2'-methylenebis[6-[(4 / 2-hydroxy-2,5 / 3,6-dimethylphenyl)methyl]-4-methylphenol], 2,2'-methylenebis[6-[(4-hydroxy-3,5-dimethylphenyl)methyl]-4-methylphenol], 2,2'-methylenebis[6-[(4 / 2-hydroxy-2,3,5 / 3,4,6-trimethylphenyl)methyl]-4-methylphenol], 2,2'-methylenebis[6-[(4-hydroxy-2,3,5-trimethylphenyl)methyl]-4-methylphenol], 4,4'-methylenebis[2-[(2,4-dihydroxyphenyl)methyl]-6-methylphenol], 4,4'-methylenebis[2-[(2,4-dihydroxyphenyl)methyl]-3,6-dimethylphenol], 4,4'-methylenebis[2-[(2,4-dihydroxy-3-methylphenyl)methyl]-3,6-dimethylphenol], 4,4'-methylenebis[2-[(2,3,4-trihydroxyphenyl)methyl]-3,6-dimethylphenol], 6,6'-methylenebis[4-[(4-hydroxy-3,5-dimethylphenyl)methyl]-1,2,3-benzenetriol], 4,4'-cyclohexylidenebis[2-cyclohexyl-6-[(2-hydroxy-5-methylphenyl)methyl]phenol], 4,4'-cyclohexylidenebis[2-cyclohexyl-6-[(4-hydroxy-3,5-dimethylphenyl)methyl]phenol], 4,4'-Cyclohexylidenebis[2-cyclohexyl-6-[(4-hydroxy-2-methyl-5-cyclohexylphenyl)methyl]phenol], 4,4'-cyclohexylidenebis[2-cyclohexyl-6-[(2,3,4-trihydroxyphenyl)methyl]phenol], 4,4',4'',4'''-(1,2-ethanediylidene)tetrakis(2,6-dimethylphenol), 4,4',4'',4'''-(1,4-phenylenedimethylidene)tetrakis(2,6-dimethylphenol), 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, and the like can be mentioned. Among them, 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane is preferable because it is particularly inexpensive and easily available., The polyvalent phenol compound represented by the above formula (8) may be used alone or in combination of two or more kinds.,

[0045] The number of phenolic hydroxyl groups in the polyvalent phenol compound represented by the above formula (8) is not particularly limited as long as it is 2 to 6, but from the viewpoint of making it easier to control the thermosetting rate, it is preferably 2 to 4.,

[0046] Usually, oxidative polymerization of phenols having a hydrogen atom at the ortho position (for example, 2-methylphenol, 2,5-dimethylphenol, 2-phenylphenol) can form an ether bond even at the ortho position, so it is difficult to control the bonding position of the phenol compound during oxidative polymerization, and a high molecular weight polymer polymerized in a branched shape with an average number of hydroxyl groups of 3.5 or more per molecule is obtained, and finally a gel component insoluble in the solvent is generated.,

[0047] On the other hand, when a bulky substituent is present at the ortho position on one side of the phenol represented by the above formula (2), although a hydrogen atom is present at the ortho position on the opposite side, it becomes possible to control the bonding position of the phenol compound during oxidative polymerization, and polyphenylene ether with an average number of hydroxyl groups of less than 3.0 per molecule can be obtained.,

[0048] Furthermore, when a bulky substituent is present at the ortho-position on one side of the phenol represented by the above formula (2), even when a monohydric phenol having a non-bulky substituent (e.g., a hydrogen atom, an allyl group, a methyl group, an ethyl group, a methoxy group, etc.) at the ortho-position of the oxygen atom of the phenol is used as the third component, gelation does not occur, and a polyphenylene ether having an average number of hydroxyl groups of less than 3.0 per molecule can be obtained.

[0049] The molecular weight of the polyphenylene ether can be adjusted, for example, by the molar ratio of the structure of the above formula (2) to the total of the structures of the above formula (1) and the above formula (2), or by the molar ratio of the structure of the above formula (8) to the total of the structures of the above formula (1) and the above formula (8). That is, when the molar ratio of the structure of the above formula (2) or the above formula (8) is high, the achievable molecular weight (reduced viscosity) can be lowered, and when the molar ratio of the structure of the above formula (2) or the above formula (8) is low, the molecular weight (reduced viscosity) can be adjusted to be high.

[0050] Here, in the method for producing a polyphenylene ether according to the present embodiment, in the oxidative polymerization step, an aromatic solvent, which is a good solvent for the polyphenylene ether, can be used as the polymerization solvent. The good solvent for the polyphenylene ether is a solvent capable of dissolving the polyphenylene ether. Examples of such solvents include aromatic hydrocarbons such as benzene, toluene, xylene (including o-, m-, and p-isomers), ethylbenzene, and halogenated hydrocarbons such as chlorobenzene and dichlorobenzene; nitro compounds such as nitrobenzene; and the like.

[0051] In addition, as the polymerization catalyst used in the method for producing polyphenylene ether in this embodiment, a known catalyst system that can generally be used for producing polyphenylene ether can be used. As a generally known catalyst system, one composed of a transition metal ion having redox ability and an amine compound capable of forming a complex with the transition metal ion is known. For example, a catalyst system composed of a copper compound and an amine compound, a catalyst system composed of a manganese compound and an amine compound, a catalyst system composed of a cobalt compound and an amine compound, etc. Since the polymerization reaction proceeds efficiently under slightly alkaline conditions, a slight amount of alkali or a further amine compound may be added here.

[0052] Further, the polymerization catalyst preferably used is a catalyst composed of a copper compound, a halogen compound, and an amine compound as constituent components of the catalyst. More preferably, it is a catalyst containing a diamine compound represented by the following formula (14) as the amine compound.

Chemical formula

[0053] List examples of the copper compounds of the catalyst components described herein. As suitable copper compounds, cuprous compounds, cupric compounds, or mixtures thereof can be used. Examples of cupric compounds include cupric chloride, cupric bromide, cupric sulfate, cupric nitrate, etc. Examples of cuprous compounds include cuprous chloride, cuprous bromide, cuprous sulfate, cuprous nitrate, etc. Particularly preferred metal compounds among these are cuprous chloride, cupric chloride, cuprous bromide, and cupric bromide. Also, these copper salts may be synthesized at the time of use from corresponding halogens or acids with oxides (e.g., cuprous oxide), carbonates, hydroxides, etc. A frequently used method is to mix cuprous oxide exemplified above with hydrogen halide (or a solution of hydrogen halide) to prepare it.

[0054] Examples of the halogen compounds include hydrogen chloride, hydrogen bromide, hydrogen iodide, sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, potassium iodide, tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium iodide, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, etc. Also, these can be used as aqueous solutions or solutions using appropriate solvents. These halogen compounds can be used alone as components or in combination of two or more. Preferred halogen compounds are aqueous solutions of hydrogen chloride and aqueous solutions of hydrogen bromide.

[0055] The usage amounts of these compounds are not particularly limited, but it is preferably 2 times or more and 20 times or less as halogen atoms relative to the molar amount of copper atoms, and the preferred usage amount of copper atoms is in the range of 0.02 mol to 0.6 mol relative to 100 mol of the phenol compound added to the polymerization reaction.

[0056] Next, examples of diamine compounds as catalyst components are listed. For example, N,N,N’,N’-tetramethylethylenediamine, N,N,N’-trimethylethylenediamine, N,N’-dimethylethylenediamine, N,N-dimethylethylenediamine, N-methylethylenediamine, N,N,N’,N’-tetraethylethylenediamine, N,N,N’-triethylethylenediamine, N,N’-diethylethylenediamine, N,N-diethylethylenediamine, N-ethylethylenediamine, N,N-dimethyl-N’-ethylethylenediamine, N,N’-dimethyl-N-ethylethylenediamine, N-n-propylethylenediamine, N,N’-n-propylethylenediamine, N-i-propylethylenediamine, N,N’-i-propylethylenediamine, N-n-butylethylenediamine, N,N’-n-butylethylenediamine, N-i-butylethylenediamine, N,N’-i-butylethylenediamine, N-t-butylethylenediamine, N,N’-t-butylethylenediamine, N,N,N’,N’-tetramethyl-1,3-diaminopropane, N,N,N’-trimethyl-1,3-diaminopropane, N,N’-dimethyl-1,3-diaminopropane, N-methyl-1,3-diaminopropane, N,N,N’,N’-tetramethyl-1,3-diamino-1-methylpropane, N,N,N’,N’-tetramethyl-1,3-diamino-2-methylpropane, N,N,N’,N’-tetramethyl-1,4-diaminobutane, N,N,N’,N’-tetramethyl-1,5-diaminopentane, etc. are mentioned. The diamine compound preferred for this embodiment is one in which the number of carbon atoms in the alkylene group connecting two nitrogen atoms is 2 or 3. The usage amount of these diamine compounds is not particularly limited, but a range of 0.01 mol to 10 mol is preferred with respect to 100 mol of the phenol compound added to the polymerization reaction.

[0057] In addition, as a constituent component of the polymerization catalyst, a primary amine and a secondary monoamine can be included. Examples of the secondary monoamine include, but are not limited to, dimethylamine, diethylamine, di-n-propylamine, di-i-propylamine, di-n-butylamine, di-i-butylamine, di-t-butylamine, dipentylamines, dihexylamines, dioctylamines, didecylamines, dibenzylamines, methylethylamine, methylpropylamine, methylbutylamine, cyclohexylamine, N-phenylmethanolamine, N-phenylethanolamine, N-phenylpropanolamine, N-(m-methylphenyl)ethanolamine, N-(p-methylphenyl)ethanolamine, N-(2’,6’-dimethylphenyl)ethanolamine, N-(p-chlorophenyl)ethanolamine, N-ethylaniline, N-butylaniline, N-methyl-2-methylaniline, N-methyl-2,6-dimethylaniline, diphenylamine, and the like.

[0058] Furthermore, as a constituent component of the polymerization catalyst, a tertiary monoamine compound can also be included. The tertiary monoamine compound is an aliphatic tertiary amine including an alicyclic tertiary amine. For example, trimethylamine, triethylamine, tripropylamine, tributylamine, triisobutylamine, dimethylethylamine, dimethylpropylamine, allyldiethylamine, dimethyl-n-butylamine, diethylisopropylamine, N-methylcyclohexylamine, and the like can be mentioned. These tertiary monoamines can be used alone or in combination of two or more. The amount used is not particularly limited, but a range of 15 mol or less with respect to 100 mol of the phenol compound added to the polymerization reaction is preferable.

[0059] In this embodiment, there is no limitation whatsoever on adding a surfactant known to have an effect of improving polymerization activity conventionally. Examples of such a surfactant include trioctylmethylammonium chloride known under the trade names of Aliquat336 and Capriquat.

[0060] As the oxygen-containing gas in the polymerization, in addition to pure oxygen, those obtained by mixing oxygen and an inert gas such as nitrogen at an arbitrary ratio, air, and further those obtained by mixing air and an inert gas such as nitrogen at an arbitrary ratio can be used. The pressure inside the system during the polymerization reaction is sufficient at normal pressure, but it can also be used under reduced pressure or increased pressure as necessary.

[0061] The temperature of the polymerization is not particularly limited, but if it is too low, the reaction hardly proceeds, and if it is too high, there is a risk of a decrease in reaction selectivity and generation of gel. Therefore, it is in the range of 0 to 60°C, preferably 10 to 40°C.

[0062] Also, in the method for producing polyphenylene ether, polymerization can also be carried out in a poor solvent such as alcohol.

[0063] In the present embodiment, there is no particular limitation on the post-treatment method after the completion of the polymerization reaction. Usually, an acid such as hydrochloric acid or acetic acid, or ethylenediaminetetraacetic acid (EDTA) and its salts, nitrilotriacetic acid and its salts, etc. are added to the reaction solution to deactivate the catalyst. Also, a method for removing by-products of divalent phenol formed by the polymerization of polyphenylene ether can also be carried out using a conventionally known method. If the metal ions as the catalyst are substantially deactivated as described above, the mixture can be decolorized by simply heating it. Also, a method of adding a necessary amount of a known reducing agent is also possible. Examples of known reducing agents include hydroquinone and sodium dithionite.

[0064] In the method for producing polyphenylene ether, water may be added to extract the compound that deactivates the copper catalyst, and after performing liquid-liquid separation into an organic phase and an aqueous phase, the copper catalyst may be removed from the organic phase by removing the aqueous phase. This liquid-liquid separation step is not particularly limited, and examples of methods include separation by standing and separation using a centrifuge. In order to promote the above liquid-liquid separation, a known surfactant or the like may be used.

[0065] Subsequently, in the method for producing the polyphenylene ether, the organic phase containing the polyphenylene ether after liquid-liquid separation may be concentrated and dried by volatilizing the solvent.

[0066] The method for volatilizing the solvent contained in the organic phase is not particularly limited. Examples thereof include a method of transferring the organic phase to a high-temperature concentration tank to distill off the solvent for concentration, and a method of using equipment such as a rotary evaporator to distill off toluene for concentration.

[0067] The drying temperature in the drying process is preferably at least 60°C or higher, more preferably 80°C or higher, still more preferably 120°C or higher, and most preferably 140°C or higher. When drying the polyphenylene ether at a temperature of 60°C or higher, the content of high-boiling volatile components in the polyphenylene ether powder can be efficiently reduced.

[0068] In order to obtain the polyphenylene ether with high efficiency, methods such as increasing the drying temperature, increasing the degree of vacuum in the drying atmosphere, and performing stirring during drying are effective. In particular, the method of increasing the drying temperature is preferable from the viewpoint of production efficiency. The drying process preferably uses a dryer equipped with a mixing function. Examples of the mixing function include stirrer-type and tumbling-type dryers. Thereby, the throughput can be increased and the productivity can be maintained at a high level.

[0069] Further, the resin composition according to the present embodiment contains the above-described polyphenylene ether A, polyphenylene ether B, triallyl isocyanurate and / or triallyl cyanurate, and an organic peroxide, and may further contain, if desired, a crosslinking agent other than triallyl isocyanurate and / or triallyl cyanurate, a thermoplastic resin, a flame retardant, other additives, a solvent, etc. The components of the resin composition according to the present embodiment will be described below.

[0070] (Mass ratio of polyphenylene ether A and polyphenylene ether B) In this embodiment, the mass ratio of the polyphenylene ether A to the polyphenylene ether B (polyphenylene ether A: polyphenylene ether B) is preferably 80:20 to 20:80, more preferably 80:20 to 30:70, and most preferably 70:30 to 30:70. When the mass ratio is the preferred one, the cured product tends to be particularly excellent in low dielectric characteristics, copper foil peel strength, and toluene resistance as compared with the resin compositions using each polyphenylene ether alone.

[0071] (Triallyl isocyanurate and / or triallyl cyanurate) The resin composition of this embodiment contains triallyl isocyanurate and / or triallyl cyanurate as a crosslinking agent, which has the ability to cause or promote a crosslinking reaction. The mass ratio of the polyphenylene ether A and the polyphenylene ether B to triallyl isocyanurate and / or triallyl cyanurate (total mass of polyphenylene ether A + polyphenylene ether B: total mass of triallyl isocyanurate and / or triallyl cyanurate) is preferably 90:10 to 60:40, more preferably 80:20 to 70:30, from the viewpoint of being more excellent in the compatibility between triallyl isocyanurate and / or triallyl cyanurate and polyphenylene ether A and polyphenylene ether B, the coatability of the resin composition, and the characteristics of the mounted electronic circuit board.

[0072] (Crosslinking agent other than triallyl isocyanurate and / or triallyl cyanurate) In the resin composition of this embodiment, a crosslinking agent other than triallyl isocyanurate and triallyl cyanurate, which has the ability to cause or promote a crosslinking reaction, can be contained. The crosslinking agent preferably has a number average molecular weight of 4,000 or less. When the number average molecular weight of the crosslinking agent is 4,000 or less, an increase in the viscosity of the resin composition can be suppressed, and good resin fluidity during heat molding can be obtained. The number average molecular weight may be a value measured by a general molecular weight measurement method, and specifically, values measured using GPC and the like can be mentioned.

[0073] Also, from the viewpoint of the crosslinking reaction, the crosslinking agent preferably has an average of 2 or more carbon-carbon unsaturated double bonds per molecule. The crosslinking agent may be composed of one type of compound or may be composed of two or more types of compounds. The "carbon-carbon unsaturated double bond" referred to in this specification means a double bond located at the terminal branched from the main chain when the crosslinking agent is a polymer or oligomer. Examples of the carbon-carbon unsaturated double bond include the 1,2-vinyl bond in polybutadiene.

[0074] When the number average molecular weight of the crosslinking agent is less than 600, the number (average value) of carbon-carbon unsaturated double bonds per molecule of the crosslinking agent is preferably 2 to 4. When the number average molecular weight of the crosslinking agent is 600 or more and less than 1,500, the number (average value) of carbon-carbon unsaturated double bonds per molecule of the crosslinking agent is preferably 4 to 26. When the number average molecular weight of the crosslinking agent is 1,500 or more and less than 4,000, the number (average value) of carbon-carbon unsaturated double bonds per molecule of the crosslinking agent is preferably 26 to 60. When the number average molecular weight of the crosslinking agent is within the above range, when the number of carbon-carbon unsaturated double bonds is equal to or more than the above specific value, the reactivity of the crosslinking agent in the resin composition of this embodiment is further enhanced, the crosslinking density of the cured product of the resin composition is further improved, and as a result, better heat resistance can be imparted. On the other hand, when the number average molecular weight of the crosslinking agent is within the above range, when the number of carbon-carbon unsaturated double bonds is equal to or less than the above specific value, better resin fluidity during heat molding can be imparted.

[0075] Examples of the crosslinking agent include polyfunctional methacrylate compounds having two or more methacryl groups in the molecule, polyfunctional acrylate compounds having two or more acrylyl groups in the molecule, polyfunctional vinyl compounds having two or more vinyl groups in the molecule such as polybutadiene, vinylbenzyl compounds such as divinylbenzene having a vinylbenzyl group in the molecule, polyfunctional maleimide compounds having two or more maleimide groups in the molecule such as 4,4'-bismaleimidodiphenylmethane, polyfunctional acrylates having two or more acrylyl groups in the molecule such as tricyclodecane dimethanol diacrylate, and polyfunctional methacrylates having two or more acrylyl or methacryl groups in the molecule such as tricyclodecane dimethanol dimethacrylate. These crosslinking agents may be used alone or in combination of two or more. Among these crosslinking agents, it is necessary to contain at least one compound selected from triallyl isocyanurate and triallyl cyanurate. By including at least one compound selected from triallyl isocyanurate and triallyl cyanurate in the crosslinking agent, the compatibility and coatability between the crosslinking agent and the polyphenylene ether can be further improved, and when mounted on an electronic circuit board, the board characteristics tend to be further excellent.

[0076] When a crosslinking agent other than triallyl isocyanurate and / or triallyl cyanurate is included, the mass ratio of the polyphenylene ether A, polyphenylene ether B, and the crosslinking agent (total mass of polyphenylene ether A + polyphenylene ether B: total mass of the crosslinking agent including triallyl isocyanurate and triallyl cyanurate) is preferably 90:10 to 60:40, more preferably 80:20 to 70:30, from the viewpoint of further excellent compatibility between the crosslinking agent and the polyphenylene ether, coatability of the resin composition, and characteristics of the mounted electronic circuit board.

[0077] (Organic peroxide) The resin composition of this embodiment can use any organic peroxide having the ability to promote the polymerization reaction, in addition to the polyphenylene ether A, polyphenylene ether B, triallyl isocyanurate and / or triallyl cyanurate, and optionally a crosslinking agent other than triallyl isocyanurate and / or triallyl cyanurate. Examples of the organic peroxide include peroxides such as benzoyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, di-t-butyl peroxide, t-butyl cumyl peroxide, di(2-t-butylperoxyisopropyl)benzene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, dicumyl peroxide, di-t-butyl peroxyisophthalate, t-butyl peroxybenzoate, 2,2-bis(t-butylperoxy)butane, 2,2-bis(t-butylperoxy)octane, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, di(trimethylsilyl)peroxide, trimethylsilyl triphenylsilyl peroxide. Radical generators such as 2,3-dimethyl-2,3-diphenylbutane can also be used as a reaction initiator for the resin composition. Among them, from the viewpoint of providing a cured product having excellent heat resistance and mechanical properties and further having a lower dielectric tangent (more preferably, a lower dielectric constant), 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, di(2-t-butylperoxyisopropyl)benzene, and 2,5-dimethyl-2,5-di(t-butylperoxy)hexane are preferred.

[0078] The one-minute half-life temperature of the organic peroxide is preferably 155 to 195 °C, more preferably 160 to 195 °C, and even more preferably 165 to 195 °C. In this specification, the one-minute half-life temperature means the temperature at which the organic peroxide decomposes and the time for the amount of its active oxygen to become half is one minute. The one-minute half-life temperature is a value confirmed by a method in which the organic peroxide is dissolved in a solvent inert to radicals, such as benzene, etc., to a concentration of 0.05 to 0.1 mol / L, and the organic peroxide solution is thermally decomposed in a nitrogen atmosphere.

[0079] When the one-minute half-life temperature of the organic peroxide is 155 °C or higher, when the polyphenylene ether-containing resin composition is subjected to heat and pressure molding, the polyphenylene ether is sufficiently melted and then the reaction with the crosslinking agent starts, so it tends to have excellent moldability. On the other hand, when the one-minute half-life temperature of the organic peroxide is 195 °C or lower, since the decomposition rate of the organic peroxide under normal heat and pressure molding conditions (for example, the maximum temperature reached is 200 °C) is sufficient, the crosslinking reaction with the crosslinking agent can proceed efficiently and gently, so a cured product having good electrical properties (especially dielectric tangent) can be formed.

[0080] Examples of the organic peroxide having a half-life temperature of 155 to 195°C for 1 minute include, for example, t-hexylperoxy isopropyl monocarbonate (155.0°C), t-butylperoxy-3,5,5-trimethylhexanoate (166.0°C), t-butylperoxylaurate (159.4°C), t-butylperoxy isopropyl monocarbonate (158.8°C), t-butylperoxy 2-ethylhexyl monocarbonate (161.4°C), t-hexylperoxybenzoate (160.3°C), 2,5-dimethyl-2,5-di(benzoylperoxy)hexane (158.2°C), t-butylperoxyacetate (159.9°C), 2,2-di-(t-butylperoxy)butane (159.9°C), t-butylperoxybenzoate (166.8°C), n-butyl 4,4-di-(t-butylperoxy)valerate (172.5°C), di(2-t-butylperoxyisopropyl)benzene (175.4°C), dicumyl peroxide (175.2°C), di-t-hexyl peroxide (176.7°C), 2,5-dimethyl-2,5-di(t-butylperoxy)hexane (179.8°C), 2,5-dimethyl-2,5-bis(t-butylperoxy)hexyne-3 (194.3°C), t-butylcumyl peroxide (173.3°C), and the like.

[0081] From the viewpoint of increasing the reaction rate, the content of the organic peroxide is preferably 0.05 part by mass or more, more preferably 0.25 part by mass or more, and still more preferably 0.5 part by mass or more with respect to a total of 100 parts by mass of the polyphenylene ether A, the polyphenylene ether B, and the crosslinking agent (total mass of the crosslinking agent including the triallyl isocyanurate and the triallyl cyanurate). Further, from the viewpoint of keeping the dielectric constant and the dielectric loss tangent of the obtained cured product low, the content of the organic peroxide is preferably 10 parts by mass or less, more preferably 5.0 parts by mass or less, and still more preferably 2.0 parts by mass or less with respect to a total of 100 parts by mass of the polyphenylene ether A, the polyphenylene ether B, and the crosslinking agent.

[0082] Also, the content of the organic peroxide is 0.1 part by mass or more and 50 parts by mass or less, preferably 1 part by mass or more and 20 parts by mass or less, and more preferably 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the crosslinking agent.

[0083] (Thermoplastic resin) The resin composition of this embodiment may further contain a thermoplastic resin. The thermoplastic resin is preferably at least one selected from the group consisting of a block copolymer of a vinyl aromatic compound and an olefinic alkene compound and its hydrogenated product (a hydrogenated block copolymer obtained by hydrogenating a block copolymer of a vinyl aromatic compound and an olefinic alkene compound), and a homopolymer of a vinyl aromatic compound. The content of the unit derived from the vinyl aromatic compound in the above block copolymer or its hydrogenated product is preferably 20% by mass or more, more preferably 22% by mass or more, and can be 99% by mass or less. When the content of the unit derived from the vinyl aromatic compound in the above block copolymer or its hydrogenated product is 20% by mass or more, the compatibility with polyphenylene ether is further improved, and the adhesion strength with the metal foil tends to be further improved.

[0084] As the vinyl aromatic compound, it only needs to have an aromatic ring and a vinyl group in the molecule, and examples thereof include styrene. As the olefinic alkene compound, it only needs to be an alkene having a linear or branched structure in the molecule, and examples thereof include ethylene, propylene, butylene, isobutylene, butadiene, and isoprene. Among these, as the thermoplastic resin, from the viewpoint of further excellent compatibility with polyphenylene ether, styrene-butadiene block copolymer, styrene-ethylene-butadiene block copolymer, styrene-ethylene-butylene block copolymer, styrene-butadiene-butylene block copolymer, styrene-isoprene block copolymer, styrene-ethylene-propylene block copolymer, styrene-isobutylene block copolymer, hydrogenated product of styrene-butadiene block copolymer, hydrogenated product of styrene-ethylene-butadiene block copolymer, hydrogenated product of styrene-butadiene-butylene block copolymer, hydrogenated product of styrene-isoprene block copolymer, and at least one selected from the group consisting of homopolymers of styrene (polystyrene) is preferable, and one or more selected from the group consisting of styrene-butadiene block copolymer, hydrogenated product of styrene-butadiene block copolymer, and polystyrene is more preferable.

[0085] The hydrogenation rate in the hydrogenated product is not particularly limited, and a carbon-carbon unsaturated double bond derived from the olefinic alkene compound may partially remain.

[0086] The weight average molecular weight of the thermoplastic resin is preferably 10,000 to 300,000, more preferably 20,000 to 290,000, and still more preferably 30,000 to 280,000. When the weight average molecular weight is 10,000 or more, the resin composition of this embodiment tends to be more excellent in heat resistance when cured. When the weight average molecular weight is 300,000 or less, the resin composition of this embodiment tends to have better resin fluidity during heat molding. The weight average molecular weight is determined by the method described in the examples below.

[0087] The content of the thermoplastic resin is preferably 2 to 20 parts by mass, more preferably 3 to 19 parts by mass, still more preferably 4 to 18 parts by mass, and particularly preferably 5 to 17 parts by mass based on 100 parts by mass in total of the polyphenylene ether and the crosslinking agent. When the content is 2 parts by mass or more, the resin composition of the present embodiment tends to be more excellent in low dielectric constant property, low dielectric loss tangent property, and adhesion to the metal foil when cured. When the content is 20 parts by mass or less, the resin composition of the present embodiment tends to have more excellent resin fluidity during heat molding. Further, from the same viewpoint, the content of the thermoplastic resin is preferably 2 to 20 parts by mass, more preferably 3 to 19 parts by mass based on 100 parts by mass in total of the polyphenylene ether and the crosslinking agent.

[0088] In addition, the resin composition of the present embodiment may contain a thermoplastic resin other than the thermoplastic resin having the types and weight average molecular weights described above.

[0089] (Flame retardant) The resin composition of the present embodiment preferably further contains a flame retardant. The flame retardant is not particularly limited as long as it is incompatible with other components in the resin composition after curing of the resin composition from the viewpoint of improving heat resistance. Preferably, the flame retardant is incompatible with the polyphenylene ether and / or the crosslinking agent in the resin composition after curing of the resin composition. Examples of the flame retardant include inorganic flame retardants such as antimony trioxide, aluminum hydroxide, magnesium hydroxide, zinc borate; aromatic bromine compounds such as hexabromobenzene, decabromodiphenylethane, 4,4-dibromobiphenyl, ethylene bis-tetrabromophthalimide; phosphorus-based flame retardants such as resorcinol bis-diphenyl phosphate, resorcinol bis-dixylenyl phosphate, etc. These flame retardants may be used alone or in combination of two or more. Among these, the flame retardant is preferably decabromodiphenylethane from the viewpoint of being more excellent in the compatibility between the flame retardant and the polyphenylene ether, the coating property of the resin composition, and the characteristics of the mounted electronic circuit board.

[0090] The content of the flame retardant is not particularly limited. However, from the perspective of maintaining the flame retardancy of the V-0 level of UL standard 94, it is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and still more preferably 15 parts by mass or more with respect to a total of 100 parts by mass of the polyphenylene ether resin and the crosslinking agent. Further, from the perspective of maintaining a low dielectric tangent of the obtained cured product (preferably from the perspective of further maintaining a low dielectric constant), the content of the flame retardant is preferably 50 parts by mass or less, more preferably 45 parts by mass or less, and still more preferably 40 parts by mass or less.

[0091] (Silica filler) The resin composition of the present embodiment may further contain a silica filler. Examples of the silica filler include natural silica, fused silica, synthetic silica, amorphous silica, aerosil, and hollow silica. The content of the silica filler can be 10 to 300 parts by mass with respect to a total of 100 parts by mass of the polyphenylene ether and the crosslinking agent. Further, the silica filler may be surface-treated using a silane coupling agent or the like on its surface.

[0092] In addition to the flame retardant and the silica filler, the resin composition of the present embodiment may further contain additives such as a heat stabilizer, an antioxidant, a UV absorber, a surfactant, a lubricant, and a solvent. When the resin composition of the present embodiment contains a solvent, it can be in the form of a varnish in which the solid content in the resin composition is dissolved or dispersed in the solvent, and a resin film can be formed from the resin composition of the present embodiment.

[0093] (Solvent) The resin composition of the present embodiment may further contain a solvent. From the perspective of solubility, aromatic compounds such as toluene and xylene, methyl ethyl ketone (MEK), cyclopentanone, cyclohexanone, and chloroform are preferable as the solvent. These solvents may be used alone or in combination of two or more.

[0094] <Resin Film> The resin film of this embodiment contains the resin composition of this embodiment. The method for manufacturing the film is not particularly limited. For example, it can be obtained by molding the resin composition of this embodiment into a film or sheet form.

[0095] <Prepreg> The prepreg of this embodiment is a composite of a base material and the resin composition of this embodiment, and the resin composition of this embodiment may be impregnated or coated on the base material. The method for manufacturing the prepreg is not particularly limited. For example, it can be obtained by impregnating a base material into a resin composition (varnish) containing a solvent and then drying and removing the solvent component with a hot air dryer or the like.

[0096] Examples of the base material include various glass cloths such as roving cloth, cloth, chopped mat, and surfacing mat; asbestos cloth, metal fiber cloth, and other synthetic or natural inorganic fiber cloths; woven or non-woven fabrics obtained from liquid crystal fibers such as wholly aromatic polyamide fibers, wholly aromatic polyester fibers, and polybenzoxazole fibers; natural fiber cloths such as cotton cloth, linen cloth, and felt; natural cellulose-based base materials such as carbon fiber cloth, kraft paper, cotton paper, and cloth obtained from paper-glass mixed fibers; polytetrafluoroethylene porous film; and the like. Among them, glass cloth is preferred. These base materials may be used alone or in combination of two or more.

[0097] The proportion of the solid content of the resin composition of this embodiment (components other than the solvent of the resin composition) in the prepreg is preferably 30 to 80% by mass, and more preferably 40 to 70% by mass. When the above proportion is 30% by mass or more, the prepreg tends to be more excellent in insulation reliability when used for electronic substrates or the like. When the above proportion is 80% by mass or less, the prepreg tends to be more excellent in mechanical properties such as flexural modulus in applications such as electronic substrates.

[0098] <Metal-clad laminate> The metal-clad laminate of the present embodiment is obtained by laminating and curing the resin composition, resin film, or prepreg of the present embodiment and a metal foil. The metal-clad laminate preferably has a form in which a cured product of the prepreg (hereinafter, also referred to as a "cured product composite") and the metal foil are laminated and adhered, and is suitably used as a material for an electronic substrate. Examples of the metal foil include an aluminum foil and a copper foil. Among these, a copper foil is preferable because of its low electrical resistance. The cured product composite combined with the metal foil may be one sheet or a plurality of sheets, and a metal foil is laminated on one or both sides of the composite according to the application to process it into a laminate.

[0099] As a method for manufacturing a metal-clad laminate, for example, a composite (for example, the above-mentioned prepreg) composed of a resin composition and a base material is formed, and after laminating this with a metal foil, the resin composition is cured to obtain a laminate in which a cured product laminate and a metal foil are laminated. One particularly preferred application of the above metal-clad laminate is a printed wiring board. In the printed wiring board, it is preferable that at least a part of the metal foil is removed from the metal-clad laminate.

[0100] <Printed Wiring Board> In the printed wiring board of the present embodiment, a part of the metal foil is removed from the metal-clad laminate. The printed wiring board of the present embodiment can typically be formed by a method of pressure heating and molding using the prepreg of the present invention described above. Examples of the base material are the same as those described above for the prepreg. The printed wiring board of the present embodiment has excellent dielectric properties, high heat resistance, and excellent solvent resistance by including the resin composition of the present embodiment.

Examples

[0101] Hereinafter, the present embodiment will be described in more detail based on examples, but the present embodiment is not limited to the following examples.

[0102] <Polyphenylene Ether> [Production Example] · Production Example 1: Polyphenylene Ether 1 (PPE1) A 40-liter jacketed polymerization tank equipped with a sparger, a stirring turbine blade, and a baffle for introducing an oxygen-containing gas at the bottom of the overlapping tank, and a reflux condenser in the vent gas line at the upper part of the polymerization tank. While blowing nitrogen gas at a flow rate of 46.3 L / min, 3.6 g of cupric oxide, 27.1 g of a 47% by mass aqueous hydrogen bromide solution, 8.7 g of di-tert-butylethylenediamine, 42.0 g of di-n-butylamine, 128.0 g of butyldimethylamine, 14.6 kg of toluene, 2.0 g of trioctylmethylammonium chloride (R = C 8 -C 10 ) were added to make a homogeneous solution. Next, using a pump, a dropping solution of 647.8 g of 2-tert-butyl-5-methylphenol, 2352.3 g of 2,6-dimethylphenol, and 2.35 kg of toluene was started to be dropped into the polymerization tank over 35 minutes. At the same time, dry air was introduced from the bottom of the polymerization tank into the polymerization solution through the sparger at a rate of 31.5 L / min, and polymerization was started. Dry air was bubbled for 240 minutes to obtain a polymerization mixture. During the polymerization, the internal temperature was controlled to be 40 °C. The polymerization mixture (polymerization solution) at the end of polymerization was in a homogeneous solution state. Thereafter, the bubbling of dry air was stopped, and 38.73 g of sodium ethylenediaminetetraacetate (reagent manufactured by Dojindo Laboratories) was added to the polymerization mixture as a 2 kg aqueous solution. The polymerization mixture was stirred at 70 °C for 240 minutes, then allowed to stand for 20 minutes, and the organic phase and the aqueous phase were separated by liquid-liquid separation. The organic phase was concentrated by a rotary evaporator until the polymer concentration reached 30% by mass. Methanol with a weight ratio of methanol to the polymer solution of 4 was mixed with the concentrated solution to precipitate the polymer. Wet polyphenylene ether was obtained by vacuum filtration using a glass filter. Further, the wet polyphenylene ether was washed with methanol in an amount such that the weight ratio of methanol to the wet polyphenylene ether was 4. The above washing operation was performed three times. Thereafter, the wet polyphenylene ether was held at 140 °C and 1 mmHg for 120 minutes to obtain dry polyphenylene ether 1 (PPE1).

[0103] · Production Example 2: Polyphenylene ether 2 (PPE2) After starting the polymerization, the operation was carried out in the same manner as in Production Example 1 except that dry air was passed for 200 minutes to obtain polyphenylene ether (PPE2).

[0104] · Production Example 3: Polyphenylene ether 3 (PPE3) The operation was carried out in the same manner as in Production Example 1 except that a dropping solution of 1096.6 g of 2-tert-butyl-5-methylphenol, 1903.4 g of 2,6-dimethylphenol and 1.90 kg of toluene was used to obtain polyphenylene ether (PPE3).

[0105] · Production Example 4: Polyphenylene ether 4 (PPE4) The operation was carried out in the same manner as in Production Example 1 except that a dropping solution of 1417.9 g of 2-tert-butyl-5-methylphenol, 1582.1 g of 2,6-dimethylphenol and 1.58 kg of toluene was used to obtain polyphenylene ether 2 (PPE4).

[0106] · Production Example 5: Polyphenylene ether 5 (PPE5) "XYRON S203A" manufactured by Asahi Kasei Corporation was used.

[0107] · Production Example 6: Polyphenylene ether 6 (PPE6) A 40-liter jacketed polymerization tank equipped with a sparger, a stirring turbine blade, and a baffle for introducing an oxygen-containing gas at the bottom of the overlapping tank, and a reflux condenser in the vent gas line at the upper part of the polymerization tank was charged with 2.4 g of cupric oxide, 18.1 g of a 47% by mass aqueous hydrogen bromide solution, 5.8 g of di-t-butylethylenediamine, 28.1 g of di-n-butylamine, 85.6 g of butyldimethylamine, 17.9 kg of toluene, 1903.4 g of 2,6-dimethylphenol, and 1096.6 g of 2-tert-butyl-5-methylphenol while blowing nitrogen gas at a flow rate of 17.1 L / min to form a homogeneous solution. Next, dry air was introduced from the sparger into the polymerization tank at a rate of 10.5 L / min to initiate polymerization. The dry air was bubbled for 120 minutes to obtain a polymerization mixture. During the polymerization, the internal temperature was controlled to be 20°C. The polymerization mixture (polymerization solution) at the end of polymerization was in a homogeneous solution state. The bubbling of dry air was stopped, and 25.9 g of sodium ethylenediaminetetraacetate (reagent manufactured by Dojindo Laboratories) was added to the polymerization mixture as a 2 kg aqueous solution. The polymerization mixture was stirred at 70°C for 150 minutes, then allowed to stand for 20 minutes, and the organic phase and the aqueous phase were separated by liquid-liquid separation. The organic phase was concentrated by a rotary evaporator until the polymer concentration reached 25% by mass. Methanol was mixed with the above solution such that the ratio of methanol to the polymer solution was 6 to precipitate the polymer. Wet polyphenylene ether was obtained by vacuum filtration using a glass filter. Further, the wet polyphenylene ether was washed with methanol in an amount such that the ratio of methanol to the wet polyphenylene ether was 3. The above washing operation was performed three times. Then, the wet polyphenylene ether was held at 140°C and 1 mmHg for 120 minutes to obtain dry polyphenylene ether 7 (PPE6).

[0108] · Production Example 7: Polyphenylene ether 7 (PPE7) Using a dropping solution of 1720.3 g of 2-tert-butyl-5-methylphenol, 1279.7 g of 2,6-dimethylphenol and 2.68 kg of toluene, the operation was carried out in the same manner as in Production Example 1 to obtain polyphenylene ether 3 (PPE7).

[0109] · Production Example 7’: Modified polyphenylene ether 7 (modified PPE7) Into a 500 mL three-necked flask equipped with a temperature controller, a stirrer, a cooling facility and a dropping funnel, 50 g of polyphenylene ether 7 (PPE7) prepared by the above production method, 50 g of toluene, 10.2 g of chloromethylstyrene (ratio of p-chloromethylstyrene to m-chloromethylstyrene is 50 / 50, manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.43 g of tetra-n-butylammonium bromide were charged. Then, the mixture was stirred and dissolved, and the liquid temperature was set to 85 °C. An aqueous sodium hydroxide solution (7.12 g of sodium hydroxide / 7.12 g of water) was added dropwise to the mixture over 1 hour, and stirring was continued at 85 °C for 5 hours. Next, the obtained aqueous layer was removed using a separating funnel to obtain a toluene layer (polymer solution) containing the polymer. The polymer solution was mixed with methanol such that the ratio of methanol to the polymer solution was 10 to precipitate the polymer. A wet polyphenylene ether was obtained by vacuum filtration using a glass filter. Further, the wet polyphenylene ether was washed with a washing solvent (methanol: water = 80:20) in an amount such that the ratio of the washing solvent (methanol: water = 80:20) to the wet polyphenylene ether was 2.5. After performing the washing operation with the above methanol-water mixed solvent three times, the wet polyphenylene ether was washed with methanol in an amount such that the ratio of methanol to the wet polyphenylene ether was 2.5. After performing the washing operation with methanol twice, the wet polyphenylene ether was held at 100 °C and 1 mmHg for 8 hours to obtain a dry modified polyphenylene ether 7 (modified PPE7). Note that 1 From the results of 1H NMR measurement to confirm the proton peak derived from the olefin of the styryl group, it was determined that the hydroxyl group was modified to a styryl group.

[0110] ·Production Example 8: Polyphenylene Ether 8 (PPE8) A 1.5-liter jacketed reactor equipped with a sparger for introducing an oxygen-containing gas, a stirring turbine blade, and a baffle at the bottom of the reactor, and a reflux condenser in the vent gas line at the upper part of the reactor was charged with a previously adjusted mixture of 0.10 g of cuprous oxide and 0.77 g of 47% hydrogen bromide, 0.25 g of N,N'-di-t-butylethylenediamine, 3.62 g of dimethyl-n-butylamine, 1.19 g of di-n-butylamine, 894 g of toluene, 79.45 g of 2,6-dimethylphenol, and 20.55 g of 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane. Then, while vigorously stirring, air was introduced into the reactor from the sparger at a rate of 1.05 L / min, and at the same time, the polymerization temperature was adjusted by passing a heat medium through the jacket so as to maintain 20°C. 150 minutes after the start of air introduction, the air flow was stopped, and after replacing the nitrogen gas in the reactor, 1.10 g of ethylenediaminetetraacetic acid tetrasodium salt tetrahydrate (reagent manufactured by Dojindo Laboratories) was added to this polymerization mixture as a 100 g aqueous solution. Then, it was heated to 70°C, and copper extraction was carried out at 70°C for 2 hours. Thereafter, it was separated into an unmodified polyphenylene ether solution (organic phase) and an aqueous phase transferred with the catalytic metal by static separation. The above organic phase was concentrated by a rotary evaporator until the polymer concentration reached 25% by mass. Methanol was mixed with the above solution so that the ratio of methanol to the polymer solution was 6, and precipitation of the polymer was carried out. Wet polyphenylene ether was obtained by vacuum filtration using a glass filter. Further, the wet polyphenylene ether was washed with methanol in an amount such that the ratio of methanol to the wet polyphenylene ether was 3. The above washing operation was carried out three times. Then, the wet polyphenylene ether was held at 140°C and 1 mmHg for 120 minutes to obtain polyphenylene ether 8 (PPE8) in a dry state.

[0111] ·Production Example 8': Modified Polyphenylene Ether 8 (Modified PPE8) A 500 mL three-necked flask equipped with a line for introducing nitrogen gas at the upper part of the reactor and a reflux condenser in the vent gas line at the upper part of the reactor was purged with nitrogen inside the reactor. After that, 20 g of polyphenylene ether 8 (PPE8) and 0.25 g of 4-dimethylaminopyridine prepared by the above production method were charged. While stirring, 5.7 mL of triethylamine was added using a syringe. Then, 2.0 mL of methacryloyl chloride was collected in a syringe and dropped into the system at room temperature. After the dropping was completed, the flask was heated in an oil bath for 1 hour and stirring was continued at 90 °C. Then, it was further heated in an oil bath and the reaction was continued under reflux. Heating was stopped at the stage when 4 hours had elapsed since the start of reflux. After returning to room temperature, 0.66 g of methanol was added to stop the reaction. Next, the reaction solution was filtered using a glass filter to obtain a solution from which the by-produced triethylammonium salt was removed. The above solution was mixed with methanol such that the ratio of methanol to the polymer solution was 10 to precipitate the polymer. Wet polyphenylene ether was obtained by vacuum filtration using a glass filter. Further, the wet polyphenylene ether was washed with methanol in an amount such that the ratio of methanol to the wet polyphenylene ether was 2.5. The above washing operation was performed three times. Then, the wet polyphenylene ether was held at 100 °C and 1 mmHg for 8 hours to obtain dry modified polyphenylene ether 8 (modified PPE8). Note that 1 From the fact that 1H NMR measurement was performed and the proton peak derived from the olefin of the methacryl group was confirmed, it was determined that the hydroxyl group was modified to the methacryl group.

[0112] · Production Example 9: Polyphenylene ether 9 (PPE9) The operation was carried out in the same manner as in Production Example 6 except that 71.92 g of 2,6-dimethylphenol and 28.08 g of 4,4'-dihydroxy-2,2',3,3',5,5'-hexamethylbiphenyl were used to obtain polyphenylene ether 9 (PPE9).

[0113] · Production Example 9’: Modified polyphenylene ether 9 (modified PPE9) Except for using polyphenylene ether 9 (PPE9) prepared by the above manufacturing method as a raw material, the operation was carried out in the same manner as in Production Example 7' to obtain modified polyphenylene ether 9 (modified PPE9).

[0114] (Analysis of Polyphenylene Ether) For PPE1 - 9 and modified PPE7 - 9 obtained in the above production examples, the following analysis was performed. The analysis results are shown in Table 1. (1) Reduced Viscosity (ηsp / c) of Polyphenylene Ether A 0.5 g / dL chloroform solution of polyphenylene ether was prepared, and the reduced viscosity (ηsp / c) (dL / g) at 30 °C was determined using an Ubbelohde viscometer tube.

[0115] (2) Number - average Molecular Weight (Mn) and Molecular Weight Distribution (Mw / Mn) of Polyphenylene Ether As a measuring device, gel permeation chromatography (manufactured by Shimadzu Corporation, LC - 2030C Plus) was used. A calibration curve was created with standard polystyrene and ethylbenzene, and using this calibration curve, the number - average molecular weight (Mn) of the obtained polyphenylene ether was measured. As the standard polystyrene, those with molecular weights of 3,650,000, 2,170,000, 1,090,000, 681,000, 204,000, 52,000, 30,200, 13,800, 3,360, 1,300, and 550 were used. In addition, two columns of K - 805L manufactured by Showa Denko K.K. connected in series were used. Chloroform was used as the solvent, the flow rate of the solvent was 1.0 mL / min, and the measurement was carried out with the column temperature at 40 °C. As the measurement sample, a 1 g / L chloroform solution of polyphenylene ether was prepared and used. The UV wavelength of the detector was 254 nm for standard polystyrene and 283 nm for polyphenylene ether. Based on the above measurement data, the number - average molecular weight (Mn) (g / mol), weight - average molecular weight (Mw), and molecular weight distribution (Mw / Mn) were calculated from the ratio of the peak areas based on the curve showing the molecular weight distribution obtained by GPC.

[0116] (3) OH number of polyphenylene ether 5.0 mg of polyphenylene ether was weighed. Then, the weighed polyphenylene ether was dissolved in 25 mL of methylene chloride. To 2.0 mL of the prepared solution, 150 μL of an ethanol solution of 2 mass% tetraethylammonium hydroxide (TEAH) was added, and then, using a UV spectrophotometer (Hitachi, Ltd.: Model U-3210), the absorbance (Abs) at 318 nm was measured (using a cell for absorbance measurement with a cell length of 1 cm). Then, based on the measurement result, the OH number obtained from the absorbance was determined by the following formula (1). OH number (μmol / g) = [(25 × Abs) / (ε × 5)] × 10 6 ··· Formula (1) (Here, ε represents the extinction coefficient and is 4700 L / mol·cm.)

[0117] (4) OH number per molecule of polyphenylene ether Using the number average molecular weight determined by gel permeation chromatography (details are described in the above (2)), the OH number per molecule of polyphenylene ether was determined by the following formula (2). Average number of hydroxyl groups per molecule (number / molecule) = (number average molecular weight determined using gel permeation chromatography) × (OH number obtained from absorbance) / 10 6 ··· Formula (2)

[0118] (5) Long-term solubility in toluene (TL solubility) 5.0 g of polyphenylene ether and 5.0 g of toluene were weighed into a transparent screw tube made of glass. They were mixed at 20 °C using a stir bar and a magnetic stirrer. After allowing one day to pass for the mixed solution, the solution was checked and judged according to the following criteria. 〇: The solution maintains transparency. △: There is some undissolved residue. ×: It is clearly not dissolved or there is a large amount of insoluble matter.

[0119]

Table 1

[0120] <Components other than polyphenylene ether> (Triallyl isocyanurate, triallyl cyanurate) ·Triallyl isocyanurate (Product name: TAIC, manufactured by Tokyo Chemical Industry Co., Ltd., number average molecular weight: 249.3, number of unsaturated double bonds in the molecule: 3)

[0121] (Organic peroxide) ·Bis(1-tert-butylperoxy-1-methylethyl)benzene (Product name: Perbutyl P, manufactured by NOF Corporation, half-life temperature for 1 minute: 175.4 °C)

[0122] (Thermoplastic resin) ·Hydrogenated styrene-based thermoplastic resin (SEBS) (Product name: Taftec H1041, manufactured by Asahi Kasei Corporation, weight average molecular weight: about 90,000, styrene unit content: 32% by mass)

[0123] (Flame retardant) ·Decabromodiphenylethane (Product name: Saytex 8010, manufactured by Albemarle Corporation)

[0124] (Filler) ·Spherical silica (Product name: SO-C6, manufactured by Admatechs Co., Ltd.)

[0125] [Examples] As shown below, cured products of the resin compositions of each example and comparative example were prepared.

[0126] (Example 1) According to the composition and solvent shown in Table 2, a thermoplastic resin was added to 101 parts by mass of toluene, stirred and dissolved. Then, a flame retardant, spherical silica, and PPE1 and modified PPE8 synthesized by the above method were added respectively, and stirring was continued until PPE1 and modified PPE8 were dissolved. Then, triallyl isocyanurate and / or triallyl cyanurate, and an organic peroxide were added to the solution, and stirred well to obtain a varnish. After impregnating the obtained varnish into an L glass cloth, excess varnish was scraped off by passing it through a slit of a predetermined width, and it was dried in a drying oven at 130 °C for a predetermined time to remove toluene, thereby obtaining a prepreg. The obtained prepreg was cut into a predetermined size, stacked in a predetermined number, and further, while copper foils (manufactured by Furukawa Electric Co., Ltd., thickness 18 μm, F1N-WS foil) were stacked on both sides of the stacked prepregs, a vacuum press was performed to obtain a copper-clad laminate. In the process of the vacuum press, first, while applying a pressure of 40 kg / cm2, the temperature was raised from 30 °C to 200 °C at a rate of temperature increase of 2 °C / min. After the temperature reached 200 °C, the pressure 40 kg / cm 2 was maintained at 200 °C for 60 minutes while being applied. Then, the obtained copper-clad laminate was subjected to etching to remove the copper foil, thereby obtaining a laminate as a sample.

[0127] (Examples 2 to 10, Comparative Examples 1 to 15) Resin compositions, varnishes, prepregs, and copper-clad laminates were obtained according to the same conditions as in Example 1, except that the resin composition was changed as shown in Tables 2 and 3. Regarding Comparative Examples 5 and 6 using PPE5, since PPE was not completely dissolved in toluene, prepregs and copper-clad laminates could not be produced.

[0128] <Evaluation> The following evaluations were performed on each sample obtained in the above Examples and Comparative Examples. The evaluation results are shown in Tables 2 and 3.

[0129] (1) Dielectric properties of the cured product of the resin composition The dielectric constant and dielectric tangent at 10 GHz of the cured products of the resin compositions produced in the Examples and Comparative Examples were measured by the split cylinder method. As the measuring apparatus, a network analyzer (N5227B, manufactured by KEYSIGHT TECHNOLOGIES) and a split cylinder resonator (CR-710, manufactured by EM Lab Co., Ltd.) were used.

[0130] The cured product of the resin composition with a thickness of about 0.5 mm prepared by the above method was cut into a plate shape with a length of 50 mm and a width of 50 mm. Next, it was placed in an oven at 105°C ± 3°C and dried for 1 hour, and then left standing for 24 ± 2 hours in an environment of 23°C and a relative humidity of 50 ± 2%. Thereafter, the permittivity and dielectric tangent were measured at 23°C and a relative humidity of 50 ± 2% using the above measuring device. Note that the dielectric tangent of the cured product of the measured resin composition is preferably less than 0.00320, more preferably less than 0.00318, still more preferably less than 0.00316, and particularly preferably less than 0.00312 from the viewpoint of reducing transmission loss.

[0131] (2) Copper foil peeling strength (peel strength N / mm) of the cured product of the resin composition The stress when peeling the copper foil of the copper-clad laminate at a constant speed was measured. The copper-clad laminates using an 18-μm-thick copper foil (manufactured by Furukawa Electric Co., Ltd., F1N-WS foil) obtained in the above-described examples and comparative examples were cut into a size of 10 mm in width × 120 mm in length, and using an autograph (AG-I20kN manufactured by Shimadzu Corporation), the average value of the load when peeling at a speed of 50 mm / min at an angle of 90° with respect to the copper foil removal surface was measured, and the average value of three measurements was determined. Note that the calculated copper foil peeling strength of the cured product of the resin composition is preferably 0.39 N / mm or more, more preferably 0.52 N / mm or more, still more preferably 0.55 N / mm or more, and particularly preferably 0.60 N / mm or more from the viewpoint of preventing peeling of the wiring.

[0132] (3) Solvent resistance (toluene immersion test) of the cured product of the resin composition The cured products of the resin composition with a thickness of about 0.5 mm obtained in the above-described examples and comparative examples were cut into a length of 50 mm and a width of 5 mm, immersed in a sufficient amount of toluene at 20°C for 24 h, and then the mass loss was evaluated according to the following criteria. 〇: When the mass loss before and after immersion is less than 0.5 mass% △: When the mass loss before and after immersion is 0.5 mass% or more and less than 1 mass% ×: When the mass loss before and after immersion is 1 mass% or more

[0133]

Table 2

[0134]

Table 3

[0135] As shown in Table 2 and Table 3, by using PPE1 to 4 and modified PPE7 to 9 in combination, a resin composition and a cured product thereof having excellent dielectric properties, copper foil peel strength, and toluene resistance were obtained.

Industrial Applicability

[0136] The resin composition containing the polyphenylene ether of the present invention and the cured product thereof are excellent in dielectric properties, heat resistance, and solvent resistance, and thus have industrial utility value as electronic material applications and modifier applications.

Claims

1. (A) Polyphenylene ether A, which contains a repeating unit derived from phenol represented by the following formula (1) and a repeating unit derived from phenol represented by the following formula (2), and has a molecular weight distribution (Mw / Mn) of 2.0 to 6.0 as determined by gel permeation chromatography (GPC) and a number of OH groups per molecule of 0.8 to 3.0 per molecule; (B) polyphenylene ether B, which contains a repeating unit derived from a phenol represented by the following formula (1) and has, in its molecular skeleton, at least one partial structure selected from the group consisting of the following formulas (4), (5), (6), and (7) (excluding those corresponding to the polyphenylene ether A); (C) triallyl isocyanurate and / or triallyl cyanurate, (C') a crosslinking agent other than triallyl isocyanurate and triallyl cyanurate as an optional component, A resin composition comprising (D) an organic peroxide. 【Chemistry 1】 (In formula (1), R 11 each independently represents an optionally substituted saturated hydrocarbon group having 1 to 6 carbon atoms, an optionally substituted aryl group having 6 to 12 carbon atoms, or a halogen atom; R 12 are each independently a hydrogen atom, an optionally substituted hydrocarbon group having from 1 to 6 carbon atoms, an optionally substituted aryl group having from 6 to 12 carbon atoms, or a halogen atom. 【Chemistry 2】 (In formula (2), R 22 are each independently a hydrogen atom, an optionally substituted saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, an optionally substituted aryl group having 6 to 12 carbon atoms, or a halogen atom; 22 are not both hydrogen atoms, and R 21 is a partial structure represented by the following formula (3). 【Chemistry 3】 (In formula (3), R 31 each independently represents a linear alkyl group having 1 to 8 carbon atoms which may be substituted, or two R 31 is a cyclic alkyl structure having 1 to 8 carbon atoms bonded to R 32 each independently represents an optionally substituted alkylene group having 1 to 8 carbon atoms; each b independently represents 0 or 1; R 33 is a hydrogen atom, an optionally substituted alkyl group having 1 to 8 carbon atoms, or an optionally substituted phenyl group. 【Chemistry 4】 【Chemistry 5】 【Chemistry 6】 (In formula (6), R ６ is a hydrogen atom or a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms, and the saturated or unsaturated hydrocarbon may have a substituent within the range satisfying the condition of having 1 to 10 carbon atoms. 【Chemistry 7】 (In formula (7), R ７ is a saturated or unsaturated divalent hydrocarbon group having 1 to 10 carbon atoms, and the saturated or unsaturated divalent hydrocarbon may have a substituent within the range satisfying the condition of having 1 to 10 carbon atoms; R ８ is a hydrogen atom or a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms, and the saturated or unsaturated hydrocarbon may have a substituent within the range satisfying the condition of having 1 to 10 carbon atoms.

2. The resin composition according to claim 1, wherein the partial structure represented by the formula (3) is a t-butyl group.

3. 2. The resin composition according to claim 1, wherein the polyphenylene ether (B) further contains a structural unit derived from a phenol represented by the following formula (8): 【Chemistry 8】 (In formula (8), X is an arbitrary linking group having a valence of a, a is an integer from 2 to 6, and R ９ is either a linear alkyl group having 1 to 8 carbon atoms or a partial structure represented by the above formula (3), and is bonded to at least one of the carbon atoms at the 2nd or 6th position, with the carbon atom of the benzene ring to which -O- is bonded being the 1st position, and each k is independently an integer of 1 to 4. R in the above formula (8) ９ Among them, the partial structure represented by the above formula (3) and R ２１ The partial structures represented by the above formula (3) may be the same or different.

4. 2. The resin composition according to claim 1, wherein the polyphenylene ether (B) further contains a repeating unit derived from a phenol of the above formula (2).

5. 2. The resin composition according to claim 1, wherein in the polyphenylene ether A (A), a content of the repeating unit derived from phenol of the formula (1) is 55 mol% or more and less than 90 mol%, and a content of the repeating unit derived from phenol of the formula (2) is more than 10 mol% and 45 mol% or less, relative to a total of 100 mol% of the repeating units of the formulas (1) and (2).

6. The resin composition according to claim 1, characterized in that the polyphenylene ether A (A) has a reduced viscosity (ηsp / c) of 0.13 to 0.30 dL / g measured in a chloroform solution having a concentration of 0.5 g / dL at 30°C.

7. The resin composition according to claim 1, characterized in that the mass ratio (A:B) of the polyphenylene ether A (A) to the polyphenylene ether B (B) is 80:20 to 20:

80.

8. The resin composition according to claim 1, characterized in that the mass ratio ((A+B):(C+C') of the total mass of the polyphenylene ether A (A) and the polyphenylene ether B (B) to the total mass of the triallyl isocyanurate and / or triallyl cyanurate (C) and the crosslinking agent other than triallyl isocyanurate and triallyl cyanurate (C') is 90:10 to 60:

40.

9. The resin composition according to claim 1, characterized in that the resin composition contains 0.05 parts by mass or more and 10 parts by mass or less of the organic peroxide (D) relative to a total of 100 parts by mass of the polyphenylene ether (A), the polyphenylene ether (B), the triallyl isocyanurate and / or triallyl cyanurate (C), and the crosslinking agent other than triallyl isocyanurate and triallyl cyanurate (C').

10. The resin composition according to claim 1, wherein the organic peroxide (D) has a one-minute half-life temperature of 155°C to 195°C.

11. The resin composition according to claim 1 , further comprising a silica filler as a filler.

12. The resin composition according to claim 1, further comprising a flame retardant, the flame retardant being incompatible with other components contained in the resin composition after the resin composition is cured.

13. A resin film comprising the resin composition according to any one of claims 1 to 12.

14. A prepreg, which is a composite of a substrate and the resin composition according to any one of claims 1 to 12.

15. The prepreg according to claim 14, wherein the base material is a glass cloth.

16. A metal-clad laminate comprising a laminate of the cured resin film according to claim 13 and a metal foil.

17. A metal-clad laminate comprising a cured product of the prepreg according to claim 14 and a metal foil.

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