CN111253855A - Resin composition - Google Patents

Abstract

The present invention provides a resin composition which can obtain a cured product having a low linear thermal expansion coefficient in the Z direction (thickness direction when a layered cured product is obtained) and excellent flexibility. The present invention is a resin composition comprising (A) an epoxy resin, (B) a curing agent, and (C) a polyimide resin, wherein the component (B) comprises (B-1) a trifunctional or higher maleimide compound.

Description

Resin composition

Technical Field

The present invention relates to a resin composition comprising an epoxy resin and a curing agent; a cured product of the resin composition; a resin sheet comprising the above resin composition; a multilayer flexible substrate including an insulating layer formed of the resin composition; and a semiconductor device including the multilayer flexible substrate.

Background

In recent years, there has been an increasing demand for thinner and lighter semiconductor components with high mounting density. In order to meet such a demand, attention has been paid to a flexible substrate used as a base substrate for a semiconductor device. The flexible substrate can be thin and lightweight compared to a rigid substrate. In addition, since the flexible substrate is flexible and deformable, it can be mounted by bending it.

Flexible substrates are typically manufactured by performing the following steps: preparing a three-layer film formed by a polyimide film, a copper foil and an adhesive, or a two-layer film formed by a polyimide film and a conductor layer; and forming a circuit by etching the conductor layer by a subtractive method. Conventionally, three-layer films have been used because they can be produced at relatively low cost. However, in a circuit board having high-density wiring, two layers of films are sometimes used in order to solve the problems of heat resistance and electrical insulation of the adhesive. However, there are problems in cost and productivity with respect to the two-layer film. In order to solve this problem, patent documents 1 to 3 disclose insulating materials for multilayer flexible substrates. Further, patent documents 4 and 5 describe polyimide resins.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2006-37083

Patent document 2: japanese patent laid-open publication No. 2016-41797

Patent document 3: japanese patent No. 6387181

Patent document 4: japanese patent No. 6240798

Patent document 5: japanese patent No. 6240799.

Disclosure of Invention

Problems to be solved by the invention

In general, when a polyimide resin is contained in a resin composition, although excellent flexibility can be achieved, the linear thermal expansion coefficient in the Z direction (thickness direction of a layered cured product) of a cured product obtained by forming the resin composition in a layer shape becomes large. For this reason, in order to further multilayering a flexible substrate using a resin composition containing a polyimide resin, it is required to reduce deformation due to thermal expansion in the Z direction at the time of multilayering.

The subject of the invention is to provide: a resin composition which can give a cured product having a low linear thermal expansion coefficient in the Z direction and excellent flexibility; a cured product of the resin composition; a resin sheet comprising the above resin composition; a multilayer flexible substrate including an insulating layer formed of the resin composition; and a semiconductor device including the multilayer flexible substrate.

Means for solving the problems

As a result of intensive studies to achieve the object of the present invention, the present inventors have found that a cured product having a low linear thermal expansion coefficient in the Z direction and excellent flexibility can be obtained by using a resin composition containing (a) an epoxy resin, (B) a curing agent, and (C) a polyimide resin, and further containing (B-1) a trifunctional or higher maleimide compound as the (B) curing agent, and have completed the present invention.

Namely, the present invention includes the following;

[1] a resin composition comprising (A) an epoxy resin, (B) a curing agent, and (C) a polyimide resin, wherein the component (B) comprises (B-1) a trifunctional or higher maleimide compound;

[2] the resin composition according to the above [1], wherein the component (B-1) is a compound represented by the formula (B1),

[ chemical formula 1]

[ wherein X independently represents a single bond or a divalent linking group having 1 to 100 skeleton atoms selected from a carbon atom, an oxygen atom, a sulfur atom and a nitrogen atom, s represents an integer of 1 or more, and a benzene ring B¹、B²And B³Each independently optionally further substituted with 1 to 3 substituents selected from halogen atoms, alkyl groups, alkenyl groups, alkoxy groups and aryl groups.]

[3] The resin composition according to the above [1] or [2], wherein the content of the component (B) is 1 to 40% by mass, based on 100% by mass of nonvolatile components in the resin composition;

[4] the resin composition according to any one of the above [1] to [3], wherein the mass ratio of the component (B-1) to the component (B) is 10% by mass or more, assuming that the component (B) in the resin composition is 100% by mass;

[5] the resin composition according to any one of the above [1] to [4], further comprising (D) an inorganic filler, or not comprising (D) an inorganic filler, wherein the content of the component (D) is 70% by mass or less, assuming that the nonvolatile content in the resin composition is 100% by mass;

[6] the resin composition according to any one of the above [1] to [5], further comprising (D) an inorganic filler;

[7] the resin composition according to any one of the above [1] to [6], wherein a linear thermal expansion coefficient in a Z direction at 25 ℃ to 150 ℃ is 100ppm or less;

[8] the resin composition according to any one of the above [1] to [7], which is used for forming an insulating layer of a multilayer flexible substrate;

[9] a cured product of the resin composition according to any one of the above [1] to [8 ];

[10] a resin sheet comprising a support and, provided on the support, a resin composition layer formed of the resin composition according to any one of the above [1] to [8 ];

[11] a multilayer flexible substrate comprising an insulating layer formed by curing the resin composition according to any one of the above [1] to [8 ];

[12] a semiconductor device comprising the multilayer flexible substrate according to [11 ].

ADVANTAGEOUS EFFECTS OF INVENTION

The present invention provides a resin composition which can give a cured product having a low linear thermal expansion coefficient in the Z direction (thickness direction when a layered cured product is obtained) and excellent flexibility; a cured product of the resin composition; a resin sheet comprising the above resin composition; a multilayer flexible substrate including an insulating layer formed of the resin composition; and a semiconductor device including the multilayer flexible substrate.

Detailed Description

The present invention will be described in detail below with reference to preferred embodiments thereof. However, the present invention is not limited to the following embodiments and examples, and can be implemented by arbitrarily changing the embodiments without departing from the scope of the claims and the equivalent scope thereof.

< resin composition >

The resin composition of the present invention comprises (A) an epoxy resin, (B) a curing agent, and (C) a polyimide resin. (B) Component (B) contains a trifunctional or higher maleimide compound (B-1).

By using such a resin composition, a cured product having a low linear thermal expansion coefficient in the Z direction and excellent flexibility can be obtained.

The resin composition of the present invention may further contain an arbitrary component in addition to the epoxy resin (a), the curing agent (B), and the polyimide resin (C). Examples of the optional components include (D) an inorganic filler, (E) a curing accelerator, (F) an organic solvent, and (G) other additives. Hereinafter, each component contained in the resin composition will be described in detail.

(A) epoxy resin

The resin composition of the present invention contains (a) an epoxy resin.

Examples of the epoxy resin (A) include a biphenol-type epoxy resin, a bisphenol A-type epoxy resin, a bisphenol F-type epoxy resin, a bisphenol S-type epoxy resin, a bisphenol AF-type epoxy resin, a dicyclopentadiene-type epoxy resin, a trisphenol-type epoxy resin, a naphthol novolac-type epoxy resin, a phenol novolac-type epoxy resin, a tert-butyl-catechol-type epoxy resin, a naphthalene-type epoxy resin, a naphthol-type epoxy resin, an anthracene-type epoxy resin, a glycidyl amine-type epoxy resin, a glycidyl ester-type epoxy resin, a cresol novolac-type epoxy resin, a biphenyl-type epoxy resin, a linear aliphatic epoxy resin, an epoxy resin having a butadiene structure, an alicyclic epoxy resin, a heterocyclic-type epoxy resin, an epoxy resin containing a spiro ring, a cyclohexane-type epoxy resin, a cyclohexane dimethanol-type epoxy resin, a naphthylene ether-type epoxy resin, Trimethylol type epoxy resins, tetraphenylethane type epoxy resins, and the like. The epoxy resin may be used alone in 1 kind, or in combination of 2 or more kinds.

The resin composition preferably contains, as the epoxy resin (a), an epoxy resin having 2 or more epoxy groups in 1 molecule. From the viewpoint of remarkably obtaining the desired effect of the present invention, the proportion of the epoxy resin having 2 or more epoxy groups in 1 molecule is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more, relative to 100% by mass of the nonvolatile component of the epoxy resin (a).

The epoxy resin includes an epoxy resin which is liquid at a temperature of 20 ℃ (hereinafter sometimes referred to as "liquid epoxy resin") and an epoxy resin which is solid at a temperature of 20 ℃ (hereinafter sometimes referred to as "solid epoxy resin"). In one embodiment, the resin composition of the present invention comprises a liquid epoxy resin as the epoxy resin. In one embodiment, the resin composition of the present invention comprises a solid epoxy resin as the epoxy resin. For the resin composition of the present invention, as the epoxy resin, only a liquid epoxy resin may be contained, or only a solid epoxy resin may be contained, but preferably a liquid epoxy resin and a solid epoxy resin are contained in combination.

As the liquid epoxy resin, a liquid epoxy resin having 2 or more epoxy groups in 1 molecule is preferable.

As the liquid epoxy resin, bisphenol a type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, phenol novolac type epoxy resin, alicyclic epoxy resin having an ester skeleton, cyclohexane type epoxy resin, cyclohexane dimethanol type epoxy resin, glycidyl amine type epoxy resin, and epoxy resin having a butadiene structure are preferable.

Specific examples of the liquid epoxy resin include "HP 4032", "HP 4032D" and "HP 4032 SS" (naphthalene type epoxy resin) manufactured by DIC corporation; "828 US", "828 EL", "jER 828 EL", "825", "EPIKOTE 828 EL" (bisphenol A type epoxy resin) manufactured by Mitsubishi chemical company; "jER 807" and "1750" (bisphenol F type epoxy resin) manufactured by Mitsubishi chemical corporation; "jER 152" (phenol novolac type epoxy resin) manufactured by mitsubishi chemical corporation; "630" and "630 LSD" (glycidyl amine type epoxy resins) manufactured by mitsubishi chemical corporation; "ZX 1059" (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) manufactured by Nissian Ciki Kaisha; "EX-721" (glycidyl ester type epoxy resin) manufactured by Nagase ChemteX; "Celloxide 2021P" (alicyclic epoxy resin having an ester skeleton) manufactured by Dailuo corporation; "PB-3600" manufactured by Daxylonite, JP-100 "and JP-200" manufactured by Nippon Caoda (a butadiene-structured epoxy resin); "ZX 1658" and "ZX 1658 GS" (liquid 1, 4-glycidylcyclohexane-type epoxy resins) manufactured by Nippon iron and Japan chemical Co., Ltd. These can be used alone in 1 kind, also can be combined with more than 2 kinds.

The solid epoxy resin is preferably a solid epoxy resin having 3 or more epoxy groups in 1 molecule, and more preferably an aromatic solid epoxy resin having 3 or more epoxy groups in 1 molecule.

As the solid epoxy resin, a biphenol-type epoxy resin, a naphthalene-type tetrafunctional epoxy resin, a cresol novolak-type epoxy resin, a dicyclopentadiene-type epoxy resin, a trisphenol-type epoxy resin, a naphthol-type epoxy resin, a biphenyl-type epoxy resin, a naphthylene ether-type epoxy resin, an anthracene-type epoxy resin, a bisphenol a-type epoxy resin, a bisphenol AF-type epoxy resin, and a tetraphenylethane-type epoxy resin are preferable.

Specific examples of the solid epoxy resin include "HP 4032H" (naphthalene type epoxy resin) manufactured by DIC; "HP-4700" and "HP-4710" (naphthalene type tetrafunctional epoxy resins) manufactured by DIC; "N-690" (cresol novolac type epoxy resin) manufactured by DIC; "N-695" (cresol novolac type epoxy resin) manufactured by DIC; "HP-7200" (dicyclopentadiene type epoxy resin) manufactured by DIC; "HP-7200 HH", "HP-7200H", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S" and "HP 6000" (naphthylene ether type epoxy resins) manufactured by DIC; EPPN-502H (trisphenol type epoxy resin) manufactured by Nippon chemical Co., Ltd.; "NC 7000L" (naphthol novolac type epoxy resin) manufactured by japan chemicals); "NC 3000H", "NC 3000L" and "NC 3100" (biphenyl type epoxy resin) manufactured by japan chemical company; ESN475V (naphthol type epoxy resin) manufactured by Nippon iron and gold Chemicals; ESN485 (naphthol novolac type epoxy resin) manufactured by Nippon iron and gold Chemicals, Ltd; "YX 4000H", "YX 4000", "YL 6121" (biphenyl type epoxy resin) manufactured by Mitsubishi chemical company; "YX 4000 HK" (bisphenol type epoxy resin) manufactured by Mitsubishi chemical corporation; YX8800 (anthracene-based epoxy resin) available from Mitsubishi chemical corporation; "YX 7700" (novolac-type epoxy resin containing a xylene structure) manufactured by mitsubishi chemical corporation; PG-100 and CG-500 manufactured by Osaka gas chemical company; "YL 7760" (bisphenol AF type epoxy resin) manufactured by Mitsubishi chemical corporation; "YL 7800" (fluorene-based epoxy resin) manufactured by Mitsubishi chemical corporation; "jER 1010" (solid bisphenol a type epoxy resin) manufactured by mitsubishi chemical corporation; "jER 1031S" (tetraphenylethane-type epoxy resin) manufactured by Mitsubishi chemical corporation, and the like. These can be used alone in 1 kind, also can be combined with more than 2 kinds.

When a liquid epoxy resin and a solid epoxy resin are used in combination as the epoxy resin (a), the amount ratio thereof (liquid epoxy resin: solid epoxy resin) is preferably 1:1 to 1:50, more preferably 1:3 to 1:30, and particularly preferably 1:5 to 1:20 in terms of mass ratio. By setting the amount ratio of the liquid epoxy resin to the solid epoxy resin within the above range, the desired effects of the present invention can be remarkably obtained.

(A) The epoxy equivalent of the epoxy resin is preferably 50g/eq to 5000g/eq, more preferably 50g/eq to 3000g/eq, even more preferably 80g/eq to 2000g/eq, and even more preferably 110g/eq to 1000g/eq. When the amount is within this range, the crosslinking density of the cured product of the resin sheet becomes sufficient, and an insulating layer having a small surface roughness can be formed. The epoxy equivalent is the mass of the resin containing 1 equivalent of epoxy group. The epoxy equivalent can be measured according to JIS K7236.

The weight average molecular weight (Mw) of the epoxy resin (a) is preferably 100 to 5000, more preferably 250 to 3000, and even more preferably 400 to 1500, from the viewpoint of remarkably obtaining the desired effect of the present invention. The weight average molecular weight of the resin can be measured as a value in terms of polystyrene by Gel Permeation Chromatography (GPC).

(A) The content of the epoxy resin is not particularly limited, and is preferably 5% by mass or more, more preferably 10% by mass or more, further preferably 15% by mass or more, and particularly preferably 20% by mass or more, when the nonvolatile content in the resin composition is 100% by mass, from the viewpoint of remarkably obtaining the desired effect of the present invention. From the viewpoint of remarkably obtaining the desired effect of the present invention, the upper limit thereof is preferably 50% by mass or less, more preferably 40% by mass or less, further preferably 30% by mass or less, and particularly preferably 25% by mass or less.

(B) curing agent

The resin composition of the present invention contains (B) a curing agent. (B) The curing agent has a function of curing the epoxy resin (A).

(B) The content of the curing agent is not particularly limited, and from the viewpoint of remarkably obtaining the desired effect of the present invention, the nonvolatile content in the resin composition is preferably 1 mass% or more, more preferably 5 mass% or more, further preferably 8 mass% or more, and particularly preferably 10 mass% or more, when taken as 100 mass%. From the viewpoint of remarkably obtaining the desired effect of the present invention, the upper limit thereof is preferably 40% by mass or less, more preferably 30% by mass or less, further preferably 20% by mass or less, and particularly preferably 15% by mass or less.

(B) The curing agent contains (B-1) a trifunctional or higher maleimide compound.

< (B-1) trifunctional or higher maleimide compound

The trifunctional or higher maleimide compound (B-1) is a compound having 3 or more 2, 5-dihydro-2, 5-dioxo-1H-pyrrol-1-yl groups (so-called maleimide groups). (B-1) the trifunctional or higher maleimide compound is not particularly limited, and is preferably, for example, a compound represented by the formula (B1);

[ chemical formula 2]

[ wherein X's each independently represents a single bond or a divalent linking group having 1 to 100 (preferably 1 to 50, more preferably 1 to 20) skeleton atoms selected from a carbon atom, an oxygen atom, a sulfur atom and a nitrogen atom, s represents an integer of 1 or more, and a benzene ring B¹、B²And B³Each independently optionally further substituted with 1 to 3 substituents selected from the group consisting of a halogen atom, an alkyl group, an alkenyl group, an alkoxy group and an aryl group]。

In the present specification, examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom and the like.

In the present specification, the term "alkyl" refers to a straight, branched or cyclic monovalent aliphatic saturated hydrocarbon group. The "alkyl group" is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Examples of the "alkyl group" include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, cyclopentyl, and cyclohexyl. The substituent of the alkyl group in the "substituted or unsubstituted alkyl group" is not particularly limited, and examples thereof include a halogen atom, a cyano group, an alkoxy group, an amino group, a nitro group, a hydroxyl group, a carboxyl group, and a sulfo group. The number of substituents is preferably 1 to 3, more preferably 1.

In the present specification, the "alkoxy group" refers to a monovalent group (alkyl-O-) formed by bonding an alkyl group to an oxygen atom. The "alkoxy group" is preferably an alkoxy group having 1 to 6 carbon atoms, and more preferably an alkoxy group having 1 to 3 carbon atoms. Examples of the "alkoxy group" include methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, and pentyloxy.

In the present specification, the term "alkenyl group" refers to a straight, branched or cyclic monovalent unsaturated hydrocarbon group having at least 1 carbon-carbon double bond. The "alkenyl group" is preferably an alkenyl group having 2 to 6 carbon atoms, and more preferably an alkenyl group having 2 or 3 carbon atoms. Examples of the "alkenyl group" include vinyl, 1-propenyl, 2-methyl-1-propenyl, 1-butenyl, 2-butenyl, 3-methyl-2-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-methyl-3-pentenyl, 1-hexenyl, 3-hexenyl, 5-hexenyl, 2-cyclohexenyl and the like. The substituent of the alkenyl group in the "substituted or unsubstituted alkenyl group" is not particularly limited, and examples thereof include a halogen atom, a cyano group, an alkoxy group, an aryl group, a heteroaryl group, an amino group, a nitro group, a hydroxyl group, a carboxyl group, a sulfo group and the like. The number of substituents is preferably 1 to 3, more preferably 1.

In the present specification, the term "aryl" refers to a monovalent aromatic hydrocarbon group. The "aryl group" is preferably an aryl group having 6 to 14 carbon atoms, and more preferably an aryl group having 6 to 10 carbon atoms. Examples of the "aryl group" include phenyl, 1-naphthyl and 2-naphthyl groups, and a phenyl group is preferable. The substituent for the aryl group in the "substituted or unsubstituted aryl group" is not particularly limited, and examples thereof include a halogen atom, a cyano group, an alkyl group, an alkoxy group, an aryl group, a heteroaryl group, an amino group, a nitro group, a hydroxyl group, a carboxyl group, and a sulfo group. The number of substituents is preferably 1 to 3, more preferably 1.

In the present specification, the term "heteroaryl" refers to an aromatic heterocyclic group having 1 to 4 hetero atoms selected from an oxygen atom, a nitrogen atom and a sulfur atom. The "heteroaryl group" is preferably a monocyclic, bicyclic or tricyclic (preferably monocyclic) aromatic heterocyclic group of five-to twelve-membered (preferably five-or six-membered). Examples of the "heteroaryl group" include furyl, thienyl, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, 1,2, 3-oxadiazolyl, 1,2, 4-oxadiazolyl, 1,3, 4-oxadiazolyl, furazanyl, 1,2, 3-thiadiazolyl, 1,2, 4-thiadiazolyl, 1,3, 4-thiadiazolyl, 1,2, 3-triazolyl, 1,2, 4-triazolyl, tetrazolyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl and the like. The substituent of the heteroaryl group in the "substituted or unsubstituted heteroaryl group" is not particularly limited, and examples thereof include a halogen atom, a cyano group, an alkyl group, an alkoxy group, an aryl group, a heteroaryl group, an amino group, a nitro group, a hydroxyl group, a carboxyl group, and a sulfo group. The number of substituents is preferably 1 to 3, more preferably 1.

In the formula (B1), the benzene ring B¹、B²And B³Preferably without further substitution.

In the formula (B1), each X is independently preferably a divalent linking group having 1 to 100 (preferably 1 to 50, more preferably 1 to 20) skeleton atoms selected from a carbon atom, an oxygen atom, a sulfur atom and a nitrogen atom, and more preferably a divalent hydrocarbon group having 1 to 20 carbon atoms.

The "divalent linking group" in X has 1 to 100 (preferably 1 to 50, more preferably 1 to 20) skeleton atoms selected from a carbon atom, an oxygen atom, a sulfur atom and a nitrogen atom. The "divalent linking group" is preferably- [ A' -Ph ]]_a’-A’-[Ph-A’]_b’- [ wherein A' each independently represents a single bond, - (substituted or unsubstituted alkylene) -, -O-, -S-, -CO-, -SO₂-, -CONH-, -NHCO-, -COO-, or-OCO- (preferably a single bond or- (alkylene) -), a 'and b' each independently represent an integer of 0 to 2. The (c) represents a divalent group. In the present specification, "Ph" represents a 1, 4-phenylene group, a 1, 3-phenylene group or a 1, 2-phenylene group.

In the present specification, the term "alkylene group" refers to a linear, branched or cyclic divalent aliphatic saturated hydrocarbon group. Preferably an alkylene group having 1 to 6 carbon atoms, more preferably an alkylene group having 1 to 3 carbon atoms. Examples thereof include-CH₂-、-CH₂-CH₂-、-CH(CH₃)-、-CH₂-CH₂-CH₂-、-CH₂-CH(CH₃)-、-CH(CH₃)-CH₂-、-C(CH₃)₂-、-CH₂-CH₂-CH₂-CH₂-、-CH₂-CH₂-CH(CH₃)-、-CH₂-CH(CH₃)-CH₂-、-CH(CH₃)-CH₂-CH₂-、-CH₂-C(CH₃)₂-、-C(CH₃)₂-CH₂-and the like. The substituent of the alkylene group in the "substituted or unsubstituted alkylene group" is not particularly limited, and examples thereof include a halogen atom, a cyano group, an alkoxy group, an aryl group, a heteroaryl group, an amino group, a nitro group, a hydroxyl group, a carboxyl group, a sulfo group and the like. The number of substituents is preferably 1 to 3, more preferably 1.

As the "divalent linking group" in X, specifically, there may be mentioned-CH₂-、-CH₂CH₂-、-CH₂CH₂CH₂-、-CH₂CH₂CH₂CH₂-、-CH₂CH₂CH₂CH₂CH₂-、-CH(CH₃)-、-C(CH₃)₂-、-Ph-、-Ph-Ph-、-CH₂-Ph-CH₂-、-CH₂-Ph-Ph-CH₂-、-O-、-CO-、-SO₂-、-NHCO-、-CONH-、-OCO-、-COO-、-O-Ph-O-、-O-Ph-Ph-O-、-O-Ph-SO₂-Ph-O-、-O-Ph-C(CH₃)₂-Ph-O-, etc.

Examples of the "divalent hydrocarbon group having 1 to 20 carbon atoms" in X include an alkylene group having 1 to 6 (preferably 1 to 3) carbon atoms, an arylene group having 6 to 14 (preferably 6 to 10) carbon atoms, or a divalent hydrocarbon group having 1 to 20 carbon atoms which is a combination of 2 or more of these groups. In the present specification, the term "arylene" refers to a divalent aromatic hydrocarbon group. Examples of the "arylene group" include 1, 4-phenylene, 1, 3-phenylene, 1, 2-phenylene, 1, 4-naphthylene, 1, 5-naphthylene, 1, 8-naphthylene, and 4, 4' -biphenylene.

Specific examples of the "divalent hydrocarbon group having 1 to 20 carbon atoms" in X include-CH₂-、-CH₂CH₂-、-CH₂CH₂CH₂-、-CH₂CH₂CH₂CH₂-、-CH₂CH₂CH₂CH₂CH₂-、-CH(CH₃)-、-C(CH₃)₂-、-Ph-、-Ph-Ph-、-CH₂-Ph-CH₂-、-CH₂-Ph-Ph-CH₂-and the like.

In the formula (B1), s is preferably an integer of 1 to 5, more preferably an integer of 1 to 3, and still more preferably 1 or 2.

Specific examples of the trifunctional or higher maleimide compound (B-1) include "MIR-3000" (main component: a compound of the following formula (B2)) manufactured by Nippon chemical Co., Ltd., and "BMI-2300" (main component: a compound of the following formula (B3)) manufactured by Dazai chemical Co., Ltd. (B-1) the trifunctional or higher maleimide compounds may be used alone in 1 kind or in combination with 2 or more kinds;

[ chemical formula 3]

(in the formula, s¹Represents 1 or 2. )

[ chemical formula 4]

(in the formula, s²Represents 1 or 2. ).

The content of the (B-1) trifunctional or higher maleimide compound is not particularly limited, and is preferably 0.1 mass% or more, more preferably 1 mass% or more, further preferably 2 mass% or more, and particularly preferably 3 mass% or more, based on 100 mass% of nonvolatile components in the resin composition, from the viewpoint of remarkably obtaining the desired effect of the present invention. From the viewpoint of remarkably obtaining the desired effect of the present invention, the upper limit thereof is preferably 40% by mass or less, more preferably 30% by mass or less, further preferably 20% by mass or less, and particularly preferably 10% by mass or less.

The mass ratio of the trifunctional or higher maleimide compound (B-1) to the curing agent (B) is not particularly limited, and from the viewpoint of remarkably obtaining the desired effect of the present invention, the curing agent (B) in the resin composition is preferably 10 mass% or more, more preferably 20 mass% or more, further preferably 30 mass% or more, and particularly preferably 40 mass% or more, based on 100 mass%. The upper limit thereof may be, for example, 100 mass% or less, 90 mass% or less, 80 mass% or less, 70 mass% or less, or the like.

(ii) curing agent other than the component (B-1)

The curing agent (B) may contain other curing agents in addition to the trifunctional or higher maleimide compound (B-1). The curing agent other than the component (B-1) is not particularly limited as long as it has a function of curing an epoxy resin, and examples thereof include bifunctional maleimide compounds, phenol-based curing agents, naphthol-based curing agents, acid anhydride-based curing agents, active ester-based curing agents, benzoxazine-based curing agents, cyanate-based curing agents and carbodiimide-based curing agents. Such curing agents may be used alone in 1 kind, or in combination of 2 or more kinds.

The bifunctional maleimide compound is a compound having 2 so-called maleimide groups. Specific examples of the bifunctional maleimide compound include "BMI-1000" and "BMI-7000" manufactured by Daihu chemical Co., Ltd.

As the phenol curing agent and the naphthol curing agent, a phenol curing agent having a novolac structure or a naphthol curing agent having a novolac structure is preferable from the viewpoint of heat resistance and water resistance. From the viewpoint of adhesion to an adherend, a nitrogen-containing phenol curing agent or a nitrogen-containing naphthol curing agent is preferable, and a triazine skeleton-containing phenol curing agent or a triazine skeleton-containing naphthol curing agent is more preferable. Among them, a phenol novolac resin containing a triazine skeleton is preferable from the viewpoint of satisfying heat resistance, water resistance, and adhesion at a high level. Specific examples of the phenol-based curing agent and the naphthol-based curing agent include "MEH-7700", "MEH-7810", "MEH-7851" manufactured by Minghu chemical Co., Ltd, "NHN", "CBN", "GPH" manufactured by Nippon chemical Co., Ltd, "SN-170", "SN-180", "SN-190", "SN-475", "SN-485", "SN-495", "SN-375", "SN-395", and "LA-7052", "LA-7054", "LA-3018-50P", "LA-1356", "TD 2090" and "TD-2090-60M" manufactured by DIC.

Examples of the acid anhydride-based curing agent include a curing agent having 1 or more acid anhydride groups in 1 molecule. Specific examples of the acid anhydride curing agent include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenylsuccinic anhydride, 5- (2, 5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1, 2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, biphenyl tetracarboxylic dianhydride, naphthalene tetracarboxylic dianhydride, oxydiphthalic dianhydride, 3,3 ', 4, 4' -diphenylsulfone tetracarboxylic dianhydride, 1,3,3a,4,5,9 b-hexahydro-5- (tetrahydro-2, 5-dioxo-3-furyl) -naphtho [1,2-C ] furan-1, 3-dione, ethylene glycol bis (trimellitic anhydride ester), styrene-maleic acid resin obtained by copolymerizing styrene with maleic acid, and other polymer-type acid anhydrides. As commercially available products of the acid anhydride-based curing agent, "HNA-100" and "MH-700" manufactured by Nissan chemical and chemical Co., Ltd.

The active ester-based curing agent is not particularly limited, and in general, a compound having 2 or more ester groups having high reactivity in 1 molecule, such as phenol esters, thiophenol esters, N-hydroxylamine esters, and esters of heterocyclic hydroxyl compounds, is preferably used, and the active ester-based curing agent is preferably obtained by a condensation reaction of a carboxylic acid compound and/or a thiocarboxylic acid compound with a hydroxyl compound and/or a thiol compound, and particularly, from the viewpoint of improving heat resistance, an active ester-based curing agent obtained from a carboxylic acid compound and a hydroxyl compound is preferable, and an active ester-based curing agent obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound is more preferable, and the carboxylic acid compound includes, for example, benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid, and the like, and the phenol compound or the naphthol compound includes, for example, hydroquinone, resorcinol, bisphenol a, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol a, methylated bisphenol a bisphenol F, methylated bisphenol F, phenol, o-cresol, m-cresol, p-cresol, catechol, α -naphthol, β, 1-dihydroxynaphthalene, 1-bis-phenol, a-bis-phenol, a-bis-.

Specifically, an active ester compound containing a dicyclopentadiene type diphenol structure, an active ester compound containing a naphthalene structure, an active ester compound containing an acetyl compound of phenol novolac, and an active ester compound containing a benzoyl compound of phenol novolac are preferable, and among them, an active ester compound containing a naphthalene structure and an active ester compound containing a dicyclopentadiene type diphenol structure are more preferable. The "dicyclopentadiene type diphenol structure" refers to a divalent structural unit formed from phenylene-dicyclopentylene-phenylene.

As the commercially available product of the active ester-based curing agent, there may be mentioned "EXB 9451", "EXB 9460S", "HPC-8000H", "HPC-8000-65T", "HPC-8000H-65 TM", "EXB-8000L-65 TM" (manufactured by DIC Co., Ltd.) as an active ester compound having a dicyclopentadiene type diphenol structure; "EXB 9416-70 BK" and "EXB 8150-65T" (manufactured by DIC) as active ester compounds having a naphthalene structure; "DC 808" (manufactured by mitsubishi chemical corporation) which is an active ester compound containing an acetylate of phenol novolac; "YLH 1026" (manufactured by mitsubishi chemical corporation) which is an active ester compound including a benzoyl compound of phenol novolac; "DC 808" (manufactured by mitsubishi chemical corporation) as an active ester-based curing agent which is an acetylated product of phenol novolac; "YLH 1026" (manufactured by mitsubishi chemical corporation), "YLH 1030" (manufactured by mitsubishi chemical corporation), and "YLH 1048" (manufactured by mitsubishi chemical corporation), which are active ester-based curing agents for benzoylates of phenol novolak; and the like.

Specific examples of the benzoxazine-based curing agent include "JBZ-OP 100D" and "ODA-BOZ" manufactured by JFE chemical company; HFB2006M manufactured by Showa Polymer Co., Ltd, "P-d", "F-a" manufactured by four national chemical industries, Ltd.

Examples of the cyanate ester curing agent include bifunctional cyanate ester resins such as bisphenol a dicyanate, polyphenol cyanate ester (oligo (3-methylene-1, 5-phenylene cyanate)), 4 '-methylenebis (2, 6-dimethylphenylcyanate), 4' -ethylenediphenyldicyanate, hexafluorobisphenol a dicyanate, 2-bis (4-cyanate ester) phenylpropane, 1-bis (4-cyanate ester phenylmethane), bis (4-cyanate ester-3, 5-dimethylphenyl) methane, 1, 3-bis (4-cyanate ester-1- (methylethylidene)) benzene, bis (4-cyanate ester phenyl) sulfide, and bis (4-cyanate ester phenyl) ether, and the like, Polyfunctional cyanate ester resins derived from phenol novolak, cresol novolak, and the like, prepolymers obtained by partially triazinating these cyanate ester resins, and the like. Specific examples of the cyanate ester-based curing agent include "PT 30" and "PT 60" (both of which are phenol novolac type polyfunctional cyanate ester resins), "BA 230" and "BA 230S 75" (prepolymers obtained by triazinating a part or all of bisphenol a dicyanate ester to form a trimer) manufactured by Lonza Japan.

Specific examples of the carbodiimide-based curing agent include "V-03" and "V-07" manufactured by Nisshinbo chemical Co.

When the resin composition contains a curing agent other than the component (B-1), the content thereof is not particularly limited, and from the viewpoint of remarkably obtaining the desired effect of the present invention, the nonvolatile content in the resin composition is preferably 30% by mass or less, more preferably 20% by mass or less, further preferably 10% by mass or less, and particularly preferably 7% by mass or less, assuming that 100% by mass of the nonvolatile content is contained. The lower limit is not particularly limited, but is preferably 0.1% by mass or more, more preferably 1% by mass or more, further preferably 3% by mass or more, and particularly preferably 5% by mass or more.

The amount ratio of the (A) epoxy resin to the (B) curing agent is preferably in the range of 1:0.2 to 1:2, more preferably 1:0.3 to 1:1.5, and further preferably 1:0.4 to 1:1.2 in terms of the ratio of [ total number of epoxy groups of epoxy resin ]: to [ total number of reactive groups of curing agent ]. The reactive group of the curing agent means an active hydroxyl group, an active ester group, and the like, and varies depending on the type of the curing agent. The total number of epoxy groups in the epoxy resin means a value obtained by calculating the sum of values obtained by dividing the nonvolatile matter mass of each epoxy resin by the epoxy equivalent weight for all the epoxy resins; the total number of reactive groups of the curing agent is a value obtained by calculating the sum of the nonvolatile matter mass of each curing agent divided by the reactive group equivalent for all the curing agents. When the amount ratio of the epoxy resin to the curing agent is within the above range, the heat resistance of the obtained cured product is further improved.

(C) polyimide resin

The resin composition of the present invention contains (C) a polyimide resin. (C) The polyimide resin is not particularly limited as long as it is a resin having an imide bond in a repeating unit. (C) The polyimide resin may generally include a resin obtained by imidization of a diamine compound with an acid anhydride. (C) The polyimide resin may also include a modified polyimide resin such as a siloxane-modified polyimide resin.

The diamine compound used for producing the polyimide resin (C) is not particularly limited, and examples thereof include aliphatic diamine compounds and aromatic diamine compounds.

Examples of the aliphatic diamine compound include linear aliphatic diamine compounds such as 1, 2-ethylenediamine, 1, 2-diaminopropane, 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 6-hexamethylenediamine, 1, 5-diaminopentane, and 1, 10-diaminodecane; branched aliphatic diamine compounds such as 1, 2-diamino-2-methylpropane, 2, 3-diamino-2, 3-butane and 2-methyl-1, 5-diaminopentane; alicyclic diamine compounds such as 1, 3-bis (aminomethyl) cyclohexane, 1, 4-diaminocyclohexane, and 4, 4' -methylenebis (cyclohexylamine); dimer acid-based diamines (hereinafter also referred to as "dimer diamines") and the like, and among them, dimer acid-based diamines are preferable.

The dimer acid type diamine refers to a dimer acid in which the two terminal carboxylic acid groups (-COOH) are replaced with aminomethyl groups (-CH)₂-NH₂) Or amino (-NH)₂) And a diamine compound obtained thereby. Dimer acid is a known compound obtained by dimerizing unsaturated fatty acid (preferably, unsaturated fatty acid having 11 to 22 carbon atoms, particularly preferably, unsaturated fatty acid having 18 carbon atoms), and its industrial production process has been generally standardized in the industry. Dimer acid containing 36 carbon atoms as a main component, which is obtained by dimerizing a c 18 unsaturated fatty acid such as oleic acid or linoleic acid, which is particularly inexpensive and easily available, can be easily obtained. The dimer acid may contain any amount depending on the production method, the degree of purification, and the likeAmounts of monomeric acids, trimeric acids, other polymerized fatty acids, and the like. In addition, after the polymerization reaction of the unsaturated fatty acid, a double bond remains, and in this specification, the dimer acid further contains a hydride which undergoes a hydrogenation reaction to lower the degree of unsaturation. Commercially available dimer-type diamines are available, and examples thereof include PRIAMINE1073, PRIAMINE1074, and PRIAMINE1075 manufactured by Croda Japan, VERSAMINE 551, and VERSAMINE 552 manufactured by Cognis Japan.

Examples of the aromatic diamine compound include a phenylenediamine compound, a naphthalenediamine compound, and a diphenylamine compound.

The phenylenediamine compound is a compound formed of a benzene ring having 2 amino groups, and the benzene ring may optionally have 1 to 3 substituents. The substituent herein is not particularly limited. Specific examples of the phenylenediamine compound include 1, 4-phenylenediamine, 1, 2-phenylenediamine, 1, 3-phenylenediamine, 2, 4-diaminotoluene, 2, 6-diaminotoluene, 3, 5-diaminobiphenyl, 2,4,5, 6-tetrafluoro-1, 3-phenylenediamine and the like.

The naphthalene diamine compound is a compound formed of a naphthalene ring having 2 amino groups, and the naphthalene ring may optionally have 1 to 3 substituents. The substituent herein is not particularly limited. Specific examples of the naphthalenediamine compound include 1, 5-diaminonaphthalene, 1, 8-diaminonaphthalene, 2, 6-diaminonaphthalene, and 2, 3-diaminonaphthalene.

The diphenylamine compound is a compound having 2 aniline structures in a molecule, and 2 benzene rings in each of the 2 aniline structures may optionally have 1 to 3 substituents. The substituent herein is not particularly limited. The 2 aniline structures in the diphenylamine compound may be bonded directly and/or via 1 or 2 divalent linking groups having 1 to 100 (preferably 1 to 50, more preferably 1 to 20) backbone atoms selected from carbon atoms, oxygen atoms, sulfur atoms, and nitrogen atoms. The diphenylamine compound comprises a compound having 2 aniline structures bonded at 2.

Specific examples of the "divalent linking group" in the diphenylamine compound include-NHCO-, -CONH-, -OCO-, -COO-、-CH₂-、-CH₂CH₂-、-CH₂CH₂CH₂-、-CH₂CH₂CH₂CH₂-、-CH₂CH₂CH₂CH₂CH₂-、-CH(CH₃)-、-C(CH₃)₂-、-C(CF₃)₂-、-CH=CH-、-O-、-S-、-CO-、-SO₂-、-NH-、-Ph-、-Ph-Ph-、-C(CH₃)₂-Ph-C(CH₃)₂-、-O-Ph-O-、-O-Ph-Ph-O-、-O-Ph-SO₂-Ph-O-、-O-Ph-C(CH₃)₂-Ph-O-、-C(CH₃)₂-Ph-C(CH₃)₂-、

[ chemical formula 5]

Etc. of

(in the formula, a represents a binding site).

In one embodiment, specific examples of the diphenylamine compound include 4,4 '-diamino-2, 2' -bis (trifluoromethyl) -1,1 '-biphenyl, 3, 4' -diaminodiphenyl ether, 4 '-diaminodiphenyl ether, 3' -diaminodiphenyl sulfone, 4 '-diaminodiphenyl sulfide, 4-aminophenyl-4-aminobenzoate, 1, 3-bis (3-aminophenoxy) benzene, 1, 3-bis (4-aminophenoxy) benzene, 1, 4-bis (4-aminophenoxy) benzene, 2-bis (4-aminophenyl) propane, 4' - (hexafluoroisopropylidene) diphenylamine, 2-bis [4- (4-aminophenoxy) phenyl ] propane, 2-bis [4- (4-aminophenoxy) phenyl ] hexafluoropropane, α -bis [4- (4-aminophenoxy) phenyl ] -1, 3-diisopropylbenzene, α -bis [4- (4-aminophenoxy) phenyl ] -1, 4-diisopropylbenzene, 1, 3-bis [4- (4-aminophenoxy) phenyl ] -1, 4-trimethylindane, α -bis [4- (4-aminophenoxy) phenyl ] -1, 4-trimethylindane, 2, 3-bis [4- (4-aminophenyl ] -1, 3-trimethylphenylidene ] -1, 3-bis [4- (4-aminophenyl ] -1, 3-trimethylindane, 3-trimethylphenylidene, 3-bis [ 4-trimethylindane, 3-4-trimethylphenylidene ] -2, 9-bis [ 4-trimethylphenylidene ] -1, 3-trimethylphenylidene, 3-trimethylindane, 9-trimethylphenylidene ] fluorene, 9-bis [ 4-trimethylindane, 3-trimethylbiphenyl, 9-bis [ 4-trimethylamino-4-trimethylphenylfluorene, 9-trimethylamino-4-trimethyl.

In another embodiment, examples of the diphenylamine compound include diamine compounds represented by the formula (1);

[ chemical formula 6]

[ in the formula, R¹～R⁸Each independently represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, -X⁹-R⁹or-X¹⁰-R¹⁰，R¹～R⁸At least 1 of which is-X¹⁰-R¹⁰，X⁹Each independently represents a single bond, -NR^9’-、-O-、-S-、-CO-、-SO₂-、-NR^9’CO-、-CONR^9’-, -OCO-, or-COO-, R⁹Each independently represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted alkenyl group, R^9’Each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted alkenyl group, X¹⁰Each independently represents a single bond, - (substituted or unsubstituted alkylene) -, -NH-, -O-, -S-, -CO-, -SO₂-, -NHCO-, -CONH-, -OCO-, or-COO-, R¹⁰Each independently represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group]。

In the formula (1), R¹～R⁸Each independently represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, -X⁹-R⁹or-X¹⁰-R¹⁰。R¹～R⁸Preferably each independently a hydrogen atom, or-X¹⁰-R¹⁰。R¹～R⁸At least 1 of which is-X¹⁰-R¹⁰. Preferably R¹～R⁸1 or 2 of these are-X¹⁰-R¹⁰More preferably R⁵～R⁸1 or 2 of these are-X¹⁰-R¹⁰Further, R is preferable⁵And R⁷1 or 2 of these are-X¹⁰-R¹⁰。

In one embodiment, R is preferred¹～R⁸1 or 2 of these are-X¹⁰-R¹⁰And R is¹～R⁸The others of (a) are hydrogen atoms; more preferably R⁵～R⁸1 or 2 of these are-X¹⁰-R¹⁰And R is¹～R⁸The others of (a) are hydrogen atoms; further preferred is R⁵And R⁷1 or 2 of these are-X¹⁰-R¹⁰And R is¹～R⁸The others of (a) are hydrogen atoms.

In the formula (1), X⁹Each independently represents a single bond, -NR^9’-、-O-、-S-、-CO-、-SO₂-、-NR^9’CO-、-CONR^9’-, -OCO-, or-COO-. X⁹Preferably a single bond. R⁹Each independently represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted alkenyl group. R⁹Substituted or unsubstituted alkyl groups are preferred. R^9’Each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted alkenyl group. R^9’Preferably a hydrogen atom.

In the formula (1), X¹⁰Each independently represents a single bond, - (substituted or unsubstituted alkylene) -, -NH-, -O-, -S-, -CO-, -SO₂-, -NHCO-, -CONH-, -OCO-, or-COO-. X¹⁰Preferably a single bond. R¹⁰Each independently represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group. R¹⁰Substituted or unsubstituted aryl groups are preferred.

In one embodiment, the diamine compound represented by the formula (1) is preferably a compound represented by the formula (1'),

[ chemical formula 7]

[ in the formula, R¹～R⁶And R⁸Each independently represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, -X⁹-R⁹The other symbols are the same as those in the formula (1)]。

More preferably a compound represented by the formula (1 ') (5-amino-1, 1' -biphenyl-2-yl 4-aminobenzoate);

[ chemical formula 8]

。

As the diamine compound, commercially available diamine compounds can be used, and diamine compounds synthesized by a known method can also be used. For example, the diamine compound represented by the formula (1) can be synthesized by the synthesis method described in japanese patent No. 6240798 or a method based on the synthesis method. The diamine compound may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The acid anhydride used for preparing the polyimide resin (C) is not particularly limited, and in a preferred embodiment, is aromatic tetracarboxylic dianhydride. Examples of the aromatic tetracarboxylic acid dianhydride include pyromellitic acid dianhydride, naphthalene tetracarboxylic acid dianhydride, anthracene tetracarboxylic acid dianhydride, and diphthalic acid dianhydride is preferable.

The pyromellitic dianhydride is a dianhydride of benzene having 4 carboxyl groups, and the benzene ring herein may optionally have 1 to 3 substituents. Here, the substituent is preferably selected from the group consisting of a halogen atom, a cyano group, and-X¹³-R¹³(the same as defined in the following formula (2)). Specific examples of the pyromellitic dianhydride include pyromellitic dianhydride and 1,2,3, 4-pyromellitic dianhydride.

The naphthalene tetracarboxylic dianhydride is a dianhydride of naphthalene having 4 carboxyl groups, and the naphthalene ring herein may optionally have 1 to 3 substituents. Here, the substituent is preferably selected from the group consisting of a halogen atom, a cyano group, and-X¹³-R¹³(the same as defined in the following formula (2)). Specific examples of the naphthalene tetracarboxylic dianhydride include 1,4,5, 8-naphthalene tetracarboxylic dianhydride, and 2,3,6, 7-naphthalene tetracarboxylic dianhydride.

The anthracenetetracarboxylic dianhydride is an anthracene dianhydride having 4 carboxyl groups, and the anthracene ring herein may optionally have 1 to 3 substituents. Herein, asThe substituent is preferably selected from the group consisting of a halogen atom, a cyano group, and-X¹³-R¹³(the same as defined in the following formula (2)). Specific examples of the anthracenetetracarboxylic dianhydride include 2,3,6, 7-anthracenetetracarboxylic dianhydride and the like.

The diphthalic dianhydride is a compound containing 2 phthalic anhydrides in the molecule, and 2 benzene rings of the 2 phthalic anhydrides may optionally have 1 to 3 substituents. Here, the substituent is preferably selected from the group consisting of a halogen atom, a cyano group, and-X¹³-R¹³(the same as defined in the following formula (2)). The 2 phthalic anhydrides in the diphthalic dianhydride may be bonded directly or via a divalent linking group having 1 to 100 (preferably 1 to 50, more preferably 1 to 20) backbone atoms selected from carbon atoms, oxygen atoms, sulfur atoms, and nitrogen atoms.

Examples of the diphthalic dianhydride include compounds represented by the formula (2);

[ chemical formula 9]

[ in the formula, R¹¹And R¹²Each independently represents a halogen atom, a cyano group, a nitro group, or-X¹³-R¹³，X¹³Each independently represents a single bond, -NR^13’-、-O-、-S-、-CO-、-SO₂-、-NR^13’CO-、-CONR^13’-, -OCO-, or-COO-, R¹³Each independently represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted alkenyl group, R^13’Each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted alkenyl group, Y represents a single bond, or a divalent linking group having 1 to 100 (preferably 1 to 50, more preferably 1 to 20) skeleton atoms selected from a carbon atom, an oxygen atom, a sulfur atom, and a nitrogen atom, and n and m each independently represent an integer of 0 to 3]。

In the formula (2), Y is preferably a divalent linking group having 1 to 100 (preferably 1 to 50, more preferably 1 to 20) skeleton atoms selected from a carbon atom, an oxygen atom, a sulfur atom and a nitrogen atom. n and m are preferably 0.

The "divalent linking group" in Y has 1 to 100 (preferably 1 to 50, more preferably 1 to 20) skeleton atoms selected from a carbon atom, an oxygen atom, a sulfur atom and a nitrogen atom. The "divalent linking group" is preferably- [ A-Ph ]]_a-A-[Ph-A]_b- [ wherein A each independently represents a single bond, - (substituted or unsubstituted alkylene) -, -O-, -S-, -CO-, -SO₂-, -CONH-, -NHCO-, -COO-, or-OCO-, a and b each independently represent an integer of 0 to 2 (preferably 0 or 1). The (c) represents a divalent group.

As the "divalent linking group" in Y, specifically, there may be mentioned-CH₂-、-CH₂CH₂-、-CH₂CH₂CH₂-、-CH₂CH₂CH₂CH₂-、-CH₂CH₂CH₂CH₂CH₂-、-CH(CH₃)-、-C(CH₃)₂-、-O-、-CO-、-SO₂-、-Ph-、-O-Ph-O-、-O-Ph-SO₂-Ph-O-、-O-Ph-C(CH₃)₂-Ph-O-, etc.

Specific examples of the diphthalic dianhydride include 3,3 ', 4, 4' -benzophenone tetracarboxylic dianhydride, 3,3 ', 4, 4' -diphenylether tetracarboxylic dianhydride, 3,3 ', 4, 4' -diphenylsulfone tetracarboxylic dianhydride, 3,3 ', 4, 4' -biphenyl tetracarboxylic dianhydride, 2 ', 3, 3' -biphenyl tetracarboxylic dianhydride, 2,3,3 ', 4' -benzophenone tetracarboxylic dianhydride, 2,3,3 ', 4' -diphenylether tetracarboxylic dianhydride, 2,3,3 ', 4' -diphenylsulfone tetracarboxylic dianhydride, 2 '-bis (3, 4-dicarboxyphenoxyphenyl) sulfone dianhydride, methylene-4, 4' -diphthalic dianhydride, and the like, 1, 1-ethylene-4, 4 '-diphthalic dianhydride, 2-propylene-4, 4' -diphthalic dianhydride, 1, 2-ethylene-4, 4 '-diphthalic dianhydride, 1, 3-trimethylene-4, 4' -diphthalic dianhydride, 1, 4-tetramethylene-4, 4 '-diphthalic dianhydride, 1, 5-pentamethylene-4, 4' -diphthalic dianhydride, 1, 3-bis (3, 4-dicarboxyphenyl) benzene dianhydride, 1, 4-bis (3, 4-dicarboxyphenyl) benzene dianhydride, 1, 3-bis (3, 4-dicarboxyphenoxy) benzene dianhydride, 1, 4-bis (3, 4-dicarboxyphenoxy) benzene dianhydride, 2, 2-bis (2, 3-dicarboxyphenyl) propane dianhydride, 2-bis (3, 4-dicarboxyphenyl) propane dianhydride, 4 '- (4, 4' -isopropylidenediphenoxy) diphthalic dianhydride, and the like.

As the aromatic tetracarboxylic acid dianhydride, commercially available aromatic tetracarboxylic acid dianhydrides can be used, and aromatic tetracarboxylic acid dianhydrides synthesized by a known method or a method based on the known method can also be used. The aromatic tetracarboxylic acid dianhydride may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

In one embodiment, as the acid anhydride used for forming the (C) polyimide resin, other acid anhydrides may be contained in addition to the aromatic tetracarboxylic dianhydride.

Specific examples of the other acid anhydride include 1,2,3, 4-cyclobutanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexane-1, 2,3, 4-tetracarboxylic dianhydride, cyclohexane-1, 2,4, 5-tetracarboxylic dianhydride, 3 ', 4,4 ' -dicyclohexyltetracarboxylic dianhydride, carbonyl-4, 4 ' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, methylene-4, 4 ' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, 1, 2-ethylene-4, 4 ' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, oxy-4, 4 ' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, thio-4, 4 ' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride, and aliphatic tetracarboxylic acid dianhydrides such as sulfonyl-4, 4' -bis (cyclohexane-1, 2-dicarboxylic acid) dianhydride.

The content of the structure derived from the aromatic tetracarboxylic dianhydride in the entire structure of the acid anhydride constituting the polyimide resin (C) is preferably 10 mol% or more, more preferably 30 mol% or more, further preferably 50 mol% or more, further preferably 70 mol% or more, further more preferably 90 mol% or more, and particularly preferably 100 mol%.

In one embodiment, the polyimide resin (C) preferably has a weight average molecular weight of 1,000 to 100,000.

(C) The polyimide resin can be prepared by a known method. Examples of the known method include a method in which a mixture of a diamine compound, an acid anhydride, and a solvent is heated and reacted. The amount of the diamine compound to be mixed is usually 0.5 to 1.5 molar equivalents, preferably 0.9 to 1.1 molar equivalents, relative to the acid anhydride, for example.

Examples of the solvent usable for the preparation of component (C) include amide solvents such as N, N-dimethylacetamide, N-diethylacetamide, N-dimethylformamide, and N-methyl-2-pyrrolidone; ketone solvents such as acetone, Methyl Ethyl Ketone (MEK), and cyclohexanone; ester solvents such as γ -butyrolactone; hydrocarbon solvents such as cyclohexane and methylcyclohexane. In the preparation of component (C), an imidization catalyst, an azeotropic dehydration solvent, an acid catalyst, and the like may be used as necessary. Examples of the imidization catalyst include tertiary amines such as triethylamine, triisopropylamine, triethylenediamine, N-methylpyrrolidine, N-ethylpyrrolidine, N-dimethyl-4-aminopyridine, and pyridine. Examples of the azeotropic dehydration solvent include toluene, xylene, and ethylcyclohexane. Examples of the acid catalyst include acetic anhydride. The amount of the imidization catalyst, azeotropic dehydration solvent, acid catalyst and the like to be used can be appropriately set by those skilled in the art. The reaction temperature for preparing the component (C) is usually 100 to 250 ℃.

(C) The content of the polyimide resin is not particularly limited, and is preferably 1% by mass or more, more preferably 5% by mass or more, further preferably 10% by mass or more, and particularly preferably 15% by mass or more, when the nonvolatile content in the resin composition is 100% by mass, from the viewpoint of remarkably obtaining the desired effect of the present invention. From the viewpoint of remarkably obtaining the desired effect of the present invention, the upper limit thereof is preferably 50% by mass or less, more preferably 40% by mass or less, further preferably 30% by mass or less, and particularly preferably 20% by mass or less.

(D) inorganic filler

The resin composition of the present invention may contain (D) an inorganic filler as an optional component.

(D) The material of the inorganic filler is not particularly limited, and examples thereof include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium phosphate tungstate, and the like, and silica is particularly preferable. Examples of the silica include amorphous silica, fused silica, crystalline silica, synthetic silica, hollow silica and the like. In addition, as the silica, spherical silica is preferable. (D) The inorganic filler may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

Examples of commercially available products of the inorganic filler (D) include "UFP-30" manufactured by electrochemical chemical industries, Inc.; "SP 60-05" and "SP 507-05" manufactured by Nissi iron-alloy materials Corp; "YC 100C", "YA 050C", "YA 050C-MJE", "YA 010C" manufactured by Yadama corporation; "UFP-30" manufactured by the electric chemical industry Co., Ltd.; "Silfil NSS-3N", "Silfil NSS-4N", "Silfil NSS-5N" manufactured by Deshan (Tokuyama); "SC 2500 SQ", "SO-C4", "SO-C2" and "SO-C1" manufactured by Yadama corporation; and so on.

(D) The average particle size of the inorganic filler is not particularly limited, but is preferably 20 μm or less, more preferably 10 μm or less, still more preferably 8 μm or less, yet more preferably 6 μm or less, and particularly preferably 5 μm or less, from the viewpoint of obtaining the desired effect of the present invention. From the viewpoint of obtaining the desired effect of the present invention, the lower limit of the average particle size of the inorganic filler is preferably 0.1 μm or more, more preferably 1 μm or more, further preferably 2 μm or more, further more preferably 3 μm or more, and particularly preferably 4 μm or more. The average particle diameter of the inorganic filler can be measured by a laser diffraction-scattering method based on Mie scattering theory. Specifically, the measurement can be performed by: the particle size distribution of the inorganic filler was prepared on a volume basis by using a laser diffraction scattering particle size distribution measuring apparatus, and the median particle size was defined as an average particle size. For the assay sample, the following can be used: 100mg of the inorganic filler and 10g of methyl ethyl ketone were weighed into a vial, and dispersed for 10 minutes by ultrasonic waves. The volume-based particle size distribution of the inorganic filler was measured in a flow cell system using a laser diffraction particle size distribution measuring apparatus with the use light source wavelengths being blue and red, and the average particle size was calculated as the median particle size from the obtained particle size distribution. Examples of the laser diffraction type particle size distribution measuring apparatus include "LA-960" manufactured by horiba, Inc.

The inorganic filler (D) is preferably treated with 1 or more surface-treating agents such as an aminosilane-based coupling agent, an epoxysilane-based coupling agent, a mercaptosilane-based coupling agent, an alkoxysilane compound, an organosilazane compound, and a titanate-based coupling agent, from the viewpoint of improving moisture resistance and dispersibility. Examples of commercially available surface-treating agents include "KBM 403" (3-glycidoxypropyltrimethoxysilane) available from shin-Etsu chemical Co., Ltd., "KBM 803" (3-mercaptopropyltrimethoxysilane) available from shin-Etsu chemical Co., Ltd., "KBE 903" (3-aminopropyltriethoxysilane) available from shin-Etsu chemical Co., Ltd., "KBM 573" (N-phenyl-3-aminopropyltrimethoxysilane) available from shin-Etsu chemical Co., Ltd., "SZ-31" (hexamethyldisilazane) manufactured by shin-Etsu chemical industries, "KBM 103" (phenyltrimethoxysilane) manufactured by shin-Etsu chemical industries, "KBM-4803" (long-chain epoxy silane coupling agent) manufactured by shin-Etsu chemical industries, and "KBM-7103" (3,3, 3-trifluoropropyltrimethoxysilane) manufactured by shin-Etsu chemical industries.

The degree of the surface treatment with the surface treatment agent is preferably limited to a predetermined range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, the inorganic filler is preferably surface-treated with 0.2 to 5 mass%, preferably 0.2 to 3 mass%, and preferably 0.3 to 2 mass% of a surface-treating agent, per 100 mass% of the inorganic filler.

The degree of surface treatment with the surface treatment agent can be advanced by the amount of carbon per unit surface area of the inorganic fillerAnd (6) evaluating. The amount of carbon per unit surface area of the inorganic filler is preferably 0.02mg/m from the viewpoint of improving the dispersibility of the inorganic filler²Above, more preferably 0.1mg/m²Above, more preferably 0.2mg/m²The above. On the other hand, from the viewpoint of preventing the increase in melt viscosity of the resin varnish or in the form of a sheet, it is preferably 1mg/m²The concentration is more preferably 0.8mg/m or less²The concentration is more preferably 0.5mg/m or less²The following.

(D) The amount of carbon per unit surface area of the inorganic filler can be measured after the inorganic filler after the surface treatment is subjected to a washing treatment with a solvent (for example, Methyl Ethyl Ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent may be added to the inorganic filler surface-treated with the surface treatment agent, and ultrasonic washing may be performed at 25 ℃ for 5 minutes. The supernatant liquid was removed, the solid component was dried, and then the amount of carbon per unit surface area of the inorganic filler material was measured using a carbon analyzer. As the carbon analyzer, "EMIA-320V" manufactured by horiba, Ltd., and the like can be used.

From the viewpoint of further improving the effect of the present invention, the specific surface area of the (D) inorganic filler is preferably 1m²A value of at least g, more preferably 2m²A total of 3m or more, particularly 3m²More than g. The upper limit is not particularly limited, but is preferably 50m²A ratio of 20m or less per gram²10m below/g²Less than or equal to 5 m/g²The ratio of the carbon atoms to the carbon atoms is less than g. The specific surface area of the inorganic filler material can be obtained by: according to the BET method, the specific surface area was calculated by a BET multipoint method by adsorbing nitrogen gas on the surface of the sample using a specific surface area measuring apparatus (Macsorb HM-1210, Mountech).

The content of the inorganic filler (D) is preferably 70% by mass or less, more preferably 60% by mass or less, further preferably 55% by mass or less, and particularly preferably 50% by mass or less, from the viewpoint of remarkably obtaining the desired effect of the present invention, assuming that the nonvolatile content in the resin composition is 100% by mass. When the resin composition contains the inorganic filler (D), the lower limit of the content is not particularly limited, and may be, for example, 10 mass% or more, 20 mass% or more, 30 mass% or more, 40 mass% or more, or the like.

(E) curing Accelerator

The resin composition of the present invention may contain (E) a curing accelerator as an optional component.

Examples of the curing accelerator (E) include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, and metal-based curing accelerators. Among them, preferred are phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators and metal-based curing accelerators, and more preferred are amine-based curing accelerators, imidazole-based curing accelerators and metal-based curing accelerators. The curing accelerator may be used alone in 1 kind, or in combination of 2 or more kinds.

Examples of the phosphorus-based curing accelerator include triphenylphosphine, a phosphonium borate compound, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl) triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate and the like.

Examples of the amine-based curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-Dimethylaminopyridine (DMAP), benzyldimethylamine, 2,4, 6-tris (dimethylaminomethyl) phenol, and 1, 8-diazabicyclo (5,4,0) -undecene, with 4-dimethylaminopyridine being preferred.

Examples of the imidazole-based curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1, 2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-heptadecylimidazole, 1, 2-dimethylimidazole, 2-ethylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-cyanoethyl-2, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2, 4-diamino-6- [2 ' -methylimidazolyl- (1 ') ] -ethyl-s-triazine, 2, 4-diamino-6- [2 ' -undecylimidazolyl- (1 ') ] -ethyl-s-triazine, 2, 4-diamino-6- [2 ' -ethyl-4 ' -methylimidazolyl- (1 ') ] -ethyl-s-triazine, 2, 4-diamino-6- [2 ' -methylimidazolyl- (1 ') ] -ethyl-s-triazine isocyanuric acid adduct, and mixtures thereof, Imidazole compounds such as 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4, 5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2, 3-dihydro-1H-pyrrolo [1,2-a ] benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline and 2-phenylimidazoline, and adducts of imidazole compounds with epoxy resins.

As the imidazole-based curing accelerator, commercially available products can be used, and examples thereof include "P200-H50" manufactured by Mitsubishi chemical corporation.

Examples of the guanidine-based curing accelerator include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1- (o-tolyl) guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5, 7-triazabicyclo [4.4.0] dec-5-ene, 7-methyl-1, 5, 7-triazabicyclo [4.4.0] dec-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1-dimethylbiguanide, 1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, 1- (o-tolyl) biguanide and the like.

Examples of the metal-based curing accelerator include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of the organic metal complex include organic cobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organic copper complexes such as copper (II) acetylacetonate, organic zinc complexes such as zinc (II) acetylacetonate, organic iron complexes such as iron (III) acetylacetonate, organic nickel complexes such as nickel (II) acetylacetonate, and organic manganese complexes such as manganese (II) acetylacetonate. Examples of the organic metal salt include zinc octylate, tin octylate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

When the resin composition contains the curing accelerator (E), the content thereof is not particularly limited, and when the nonvolatile content in the resin composition is 100 mass%, from the viewpoint of remarkably obtaining the desired effect of the present invention, the content is preferably 0.001 mass% or more, more preferably 0.01 mass% or more, further preferably 0.05 mass% or more, and particularly preferably 0.1 mass% or more. From the viewpoint of remarkably obtaining the desired effect of the present invention, the upper limit thereof is preferably 2% by mass or less, more preferably 1% by mass or less, further preferably 0.5% by mass or less, and particularly preferably 0.3% by mass or less.

(F) organic solvent

The resin composition of the present invention may further contain (G) an organic solvent as an optional volatile component.

Examples of the organic solvent include ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone; ester-based solvents such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, carbitol acetate, ethyl diglycol acetate (diethylene glycol monoethyl ether acetate), and γ -butyrolactone; cellosolve and carbitol solvents such as butyl carbitol; aromatic solvents such as benzene, toluene, xylene, ethylbenzene, and trimethylbenzene; amide solvents such as dimethylformamide, dimethylacetamide (DMAc), and N-methylpyrrolidone; alcohol solvents such as methanol, ethanol, and 2-methoxypropanol; and aliphatic hydrocarbon solvents such as cyclohexane and methylcyclohexane. The organic solvent may be used alone in 1 kind, or may be used in combination in 2 or more kinds at an arbitrary ratio.

< (G) other additives

The resin composition may contain other additives as optional components in addition to the above components. Examples of such additives include organic fillers, thickeners, defoaming agents, leveling agents, adhesion imparting agents, polymerization initiators, flame retardants, and the like. These additives may be used alone in 1 kind, or in combination of 2 or more kinds. The respective contents may be appropriately set by those skilled in the art.

< method for producing resin composition >

In one embodiment, the resin composition of the present invention can be produced, for example, by a method comprising the steps of: a step of adding and mixing (a) an epoxy resin, (B) a curing agent, (C) a polyimide resin (a product obtained by imidization in advance), if necessary, (D) an inorganic filler, (E) a curing accelerator, if necessary, (F) an organic solvent, if necessary, (G) other additives, if necessary, in a reaction vessel in an arbitrary order and/or partially or entirely at the same time to obtain a resin composition (hereinafter, referred to as step (1)).

In the step (1), the temperature in the process of adding each component may be appropriately set, and heating and/or cooling may be performed temporarily or throughout the process of adding each component. The specific temperature of the process of adding each component is not particularly limited, and may be, for example, 0 to 150 ℃. Stirring or shaking may be performed during the addition of the ingredients.

In the step (1), particularly when the epoxy resin (a) contains a solid epoxy resin, the following two stages are preferable: a step of adding (a) an epoxy resin, (C) a polyimide resin (a product obtained by imidization in advance), if necessary, (F) an organic solvent, and if necessary, (H) other additives to a reaction vessel in an arbitrary order and/or partially or entirely at the same time, mixing, and heating to obtain a mixture; and a step of cooling the obtained mixture, and adding and mixing (B) a curing agent, (D) an inorganic filler, if necessary, (E) a curing accelerator, if necessary, (F) an organic solvent, if necessary, (G) other additives, if necessary, in an arbitrary order and/or partially or completely simultaneously to obtain a resin composition.

After the step (1), it is preferable to further include a step of uniformly dispersing the resin composition by stirring the resin composition using a stirring device such as a rotary mixer (hereinafter referred to as step (2)). After the step (1), preferably after the step (2), a step of filtering the resin composition by using, for example, a cartridge filter is preferably further included.

< Property of resin composition >

The resin composition of the present invention comprises (a) an epoxy resin, (B) a curing agent, and (C) a polyimide resin, and the component (B) comprises (B-1) a trifunctional or higher maleimide compound, and therefore, a cured product having a low linear thermal expansion coefficient in the Z direction (thickness direction when a layered cured product is obtained) and excellent flexibility can be obtained.

Regarding the low linear thermal expansion coefficient in the Z direction, which is one of the characteristics of the resin composition of the present invention, in one embodiment, for example, when thermo-mechanical analysis is performed on a layered cured product obtained by curing the resin composition having a thickness of 50 μm by a compressive load method, the linear thermal expansion coefficient in the Z direction at 25 ℃ to 150 ℃ is preferably 100ppm or less, more preferably 80ppm or less, further preferably 70ppm or less, further more preferably 65ppm or less, and particularly preferably 60ppm or less. The lower limit is not particularly limited, and may be 1ppm or more, 2ppm or more, 3ppm or more, or the like.

Regarding the excellent flexibility which is one of the characteristics of the resin composition of the present invention, in one embodiment, for example, the number of folding endurance tests performed on a layered cured product obtained by curing the resin composition having a thickness of 40 μm is preferably 5,000 or more, more preferably 8,000 or more, further preferably 10,000 or more, and particularly preferably 11,000 or more, under the conditions of a load of 2.5N, a folding angle of 90 degrees, a folding speed of 175 times/minute, and a folding radius of 1.0mm in accordance with JIS C-5016.

< resin sheet >

The resin sheet of the present invention comprises a support and a resin composition layer formed of the resin composition of the present invention provided on the support.

The thickness of the resin composition layer is preferably 15 μm or less, more preferably 13 μm or less, and still more preferably 10 μm or less, or 8 μm or less, from the viewpoint of providing a cured product having excellent insulation properties even when the printed wiring board is made thin or when the printed wiring board is a thin film. The lower limit of the thickness of the resin composition layer is not particularly limited, and may be usually 1 μm or more, 1.5 μm or more, 2 μm or more, or the like.

Examples of the support include a film made of a plastic material, a metal foil, and a release paper, and preferably a film made of a plastic material and a metal foil.

When a film made of a plastic material is used as the support, examples of the plastic material include polyesters such as polyethylene terephthalate (hereinafter, sometimes abbreviated as "PET") and polyethylene naphthalate (hereinafter, sometimes abbreviated as "PEN"), acrylic polymers such as polycarbonate (hereinafter, sometimes abbreviated as "PC") and polymethyl methacrylate (PMMA), cyclic polyolefins, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, and polyimide. Among them, polyethylene terephthalate and polyethylene naphthalate are preferable, and particularly, inexpensive polyethylene terephthalate is preferable.

When a metal foil is used as the support, examples of the metal foil include a copper foil and an aluminum foil, and a copper foil is preferable. As the copper foil, a foil formed of a single metal of copper may be used, and a foil formed of an alloy of copper and another metal (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, or the like) may also be used.

The surface of the support to be bonded to the resin composition layer may be subjected to matte treatment, corona treatment, or antistatic treatment.

In addition, as the support, a support with a release layer having a release layer on the surface bonded to the resin composition layer can be used. Examples of the release agent used for the release layer of the support with a release layer include 1 or more release agents selected from alkyd resins, polyolefin resins, polyurethane resins, and silicone resins. As the support having a release layer, commercially available products can be used, and examples thereof include a PET film having a release layer containing an alkyd resin-based release agent as a main component, "SK-1", "AL-5" and "AL-7" manufactured by Lindedaceae, "Lumiror T60" manufactured by Toray, a "Purex" manufactured by Ditika, and a "Unipel" manufactured by Unitika.

The thickness of the support is not particularly limited, but is preferably in the range of 5 to 75 μm, and more preferably in the range of 10 to 60 μm. When a support with a release layer is used, the thickness of the entire support with a release layer is preferably in the above range.

In one embodiment, the resin sheet may further include other layers as needed. Examples of the other layer include a protective film provided on a surface of the resin composition layer not bonded to the support (i.e., a surface opposite to the support) and selected for the support. The thickness of the protective film is not particularly limited, and is, for example, 1 μm to 40 μm. By laminating the protective film, it is possible to suppress adhesion of dust or the like to the surface of the resin composition layer and generation of damage on the surface of the resin composition layer.

The resin sheet can be produced, for example, by: a resin varnish obtained by dissolving a resin composition in an organic solvent is prepared, and the resin varnish is applied to a support using a die coater or the like, and then dried to form a resin composition layer.

Examples of the organic solvent include ketones such as acetone, Methyl Ethyl Ketone (MEK), and cyclohexanone; acetates such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate; carbitols such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide (DMAc) and N-methylpyrrolidone. The organic solvent may be used alone in 1 kind, or may be used in combination of 2 or more kinds.

The drying may be carried out by a known method such as heating or blowing hot air. The drying conditions are not particularly limited, and drying is performed so that the content of the organic solvent in the resin composition layer is 10 mass% or less, preferably 5 mass% or less. For example, when a resin varnish containing 30 to 60 mass% of an organic solvent is used, the resin varnish may be dried at 50 to 150 ℃ for 3 to 10 minutes to form a resin composition layer.

The resin sheet may be wound into a roll and stored. When the resin sheet has a protective film, the protective film can be peeled off and used.

< laminated sheet >

The laminated sheet is a sheet produced by laminating and curing a plurality of resin sheets. Therefore, the laminated sheet includes a plurality of insulating layers as a cured product of the resin sheet. In general, the number of resin sheets laminated for manufacturing the laminated sheet corresponds to the number of insulating layers included in the laminated sheet. The specific number of insulating layers per 1-layer laminated sheet is usually 2 or more, preferably 3 or more, particularly preferably 5 or more, preferably 20 or less, more preferably 15 or less, particularly preferably 10 or less.

The laminated sheet is a sheet used by being bent so that one surface thereof faces each other. The minimum bend radius of the laminated sheet in bending is not particularly limited, but is preferably 0.1mm or more, more preferably 0.2mm or more, further preferably 0.3mm or more, preferably 5mm or less, more preferably 4mm or less, and particularly preferably 3mm or less.

A hole may be formed in each of the insulating layers included in the laminated sheet. The holes may function as through holes or through holes in the multilayer flexible substrate.

The laminated sheet may contain any element in addition to the insulating layer. For example, the laminated sheet may include a conductor layer as an arbitrary element. The conductor layer may be formed partially on the surface of the insulating layer or between the insulating layers. The conductor layer generally functions as a wiring in a multilayer flexible substrate.

The conductor material used in the conductor layer is not particularly limited. In a preferred embodiment, the conductor layer contains 1 or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin, and indium. The conductor material may be a single metal or an alloy. Examples of the alloy include alloys of 2 or more metals selected from the above-described group (for example, nickel-chromium alloys, copper-nickel alloys, and copper-titanium alloys). Among them, chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper as a single metal is preferable from the viewpoints of versatility of forming a conductor layer, cost, ease of patterning, and the like; and alloys such as nickel-chromium alloy, copper-nickel alloy, and copper-titanium alloy. Among them, a single metal of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper is more preferable; and nickel-chromium alloys, more preferably copper.

The conductor layer may have a single-layer structure, or may have a multilayer structure including 2 or more single metal layers or alloy layers made of different metals or alloys. When the conductor layer has a multilayer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc, or titanium, or an alloy layer of a nickel-chromium alloy.

The conductor layer may be patterned to function as a wiring.

The thickness of the conductor layer depends on the design of the multilayer flexible substrate, and is preferably 3 μm to 35 μm, more preferably 5 μm to 30 μm, further preferably 10 to 20 μm, and particularly preferably 15 to 20 μm.

The thickness of the laminated sheet is preferably 100 μm or more, more preferably 150 μm or more, particularly preferably 200 μm or more, preferably 600 μm or less, more preferably 500 μm or less, and particularly preferably 400 μm or less.

< method for producing laminated sheet >

The laminated sheet can be produced by a production method including the steps of: (a) a step of preparing a resin sheet, and (b) a step of laminating and curing a plurality of resin sheets. The order of laminating and curing the resin sheets is arbitrary as long as a desired laminated sheet can be obtained. For example, after the multilayer resin sheets are all stacked, the stacked multilayer resin sheets may be collectively cured. For example, the resin sheets to be laminated may be cured each time another resin sheet is laminated on a certain resin sheet.

Hereinafter, a preferred embodiment of the step (b) will be described. In the embodiments described below, for the sake of distinction, the resin sheets are indicated by the reference numerals as "first resin sheet" and "second resin sheet", and the insulating layers obtained by curing these resin sheets are also indicated by the reference numerals as "first insulating layer" and "second insulating layer", similarly to the resin sheets.

In a preferred embodiment, the step (b) includes the steps of:

(II) a step of curing the first resin sheet to form a first insulating layer,

(VI) a step of laminating a second resin sheet on the first insulating layer,

(VII) a step of forming a second insulating layer by curing the second resin sheet. The step (b) may include any of the following steps as necessary:

(I) a step of laminating a first resin sheet on a sheet-like support base material,

(III) a step of forming a hole in the first insulating layer,

(IV) a step of roughening the first insulating layer,

(V) forming a conductor layer on the first insulating layer.

Hereinafter, each step will be explained.

The step (I) is a step of laminating a first resin sheet on a sheet-like support base material before the step (II) as necessary. The sheet-like support substrate is a peelable member, and for example, a plate-like, sheet-like or film-like member can be used.

The lamination of the sheet-like support substrate and the first resin sheet may be performed by a vacuum lamination method. In the vacuum lamination method, the heating and pressure bonding temperature is preferably 60 to 160 ℃, more preferably 80 to 140 ℃, the heating and pressure bonding pressure is preferably 0.098 to 1.77MPa, more preferably 0.29 to 1.47MPa, and the heating and pressure bonding time is preferably 20 to 400 seconds, more preferably 30 to 300 seconds. The lamination is preferably performed under a reduced pressure of 26.7hPa or less.

The lamination can be carried out by means of a commercially available vacuum laminator. Examples of commercially available vacuum laminators include a vacuum pressure laminator manufactured by Nikko-Materials, vacuum applicators manufactured by Nikko-Materials, and batch vacuum pressure laminators.

In the case of using the sheet-like laminating material, the lamination of the sheet-like support base material and the first resin sheet can be performed, for example, by pressing the sheet-like laminating material from the support side and heat-pressure bonding the first resin sheet of the sheet-like laminating material to the sheet-like support base material. Examples of the member for heat-pressure bonding the sheet-like laminating material to the sheet-like support base material (hereinafter, also referred to as "heat-pressure bonding member" as appropriate) include a heated metal plate (SUS end plate or the like) and a metal roll (SUS roll). It is preferable that the thermocompression bonding member is not directly pressed against the sheet-like laminating material, but is pressed via an elastic material such as a heat-resistant rubber so that the first resin sheet sufficiently conforms to the surface irregularities of the sheet-like support base material.

After the lamination, the first resin sheet may be subjected to a smoothing treatment by pressing it at normal pressure (atmospheric pressure), for example, with a heat-pressure bonding member. For example, in the case of using a sheet-like laminating material, the first resin sheet of the sheet-like laminating material can be smoothed by pressing the sheet-like laminating material from the support-side heat-pressure bonding member. The pressing conditions for the smoothing treatment may be set to the same conditions as the above-described conditions for the heat and pressure bonding of the laminate. The smoothing treatment can be performed using a commercially available laminator. The lamination and smoothing processes can be performed continuously using a commercially available vacuum laminator as described above.

The step (II) is a step of curing the first resin sheet to form a first insulating layer. The conditions for heat curing of the first resin sheet are not particularly limited, and the conditions employed in forming the insulating layer of the printed wiring board can be arbitrarily applied.

In general, specific heat curing conditions vary depending on the kind of the resin composition. For example, the curing temperature is preferably 120 to 240 ℃, more preferably 150 to 220 ℃, and still more preferably 170 to 210 ℃. The curing time is preferably 5 to 120 minutes, more preferably 10 to 110 minutes, and still more preferably 20 to 100 minutes.

The first resin sheet may be preheated at a temperature lower than the curing temperature before the first resin sheet is thermally cured. For example, before the first resin sheet is thermally cured, the first resin sheet may be preheated at a temperature of 50 ℃ or higher and lower than 120 ℃ (preferably 60 ℃ or higher and 115 ℃ or lower, more preferably 70 ℃ or higher and 110 ℃ or lower) for 5 minutes or longer (preferably 5 minutes to 150 minutes, more preferably 5 minutes to 120 minutes, and further preferably 5 minutes to 100 minutes).

The step (III) is a step of opening a hole in the first insulating layer as necessary. In the step (III), a via hole, a through hole, or the like can be formed in the first insulating layer. The opening may be performed using, for example, a drill, a laser, plasma, etc., depending on the composition of the resin composition. The size and shape of the hole may be appropriately set according to the design of the multilayer flexible substrate.

The step (IV) is a step of performing roughening treatment on the first insulating layer as necessary. In general, in this step (IV), the removal of the scum is also performed. Therefore, the roughening treatment may be referred to as desmear treatment. As the roughening treatment, any of dry and wet roughening treatments may be performed. Examples of the dry roughening treatment include plasma treatment. In addition, as an example of the wet roughening treatment, there is a method of sequentially performing a swelling treatment by a swelling liquid, a roughening treatment by an oxidizing agent, and a neutralizing treatment by a neutralizing liquid.

The arithmetic average roughness (Ra) of the surface of the first insulating layer after the roughening treatment is preferably 240nm or less, more preferably 220nm or less, and further preferably 200nm or less. The lower limit is not particularly limited, and may be 30nm or more, 40nm or more, or 50nm or more.

The step (V) is a step of forming a conductor layer on the first insulating layer as necessary. Examples of the method for forming the conductor layer include plating, sputtering, and vapor deposition, and among them, plating is preferred. A preferable example is a method of forming a conductor layer having a desired wiring pattern by plating on the surface of the first insulating layer by an appropriate method such as a semi-additive method or a full-additive method. Among them, the semi-addition method is preferable from the viewpoint of ease of production.

An example of forming a conductor layer by a semi-additive method is shown below. First, a plating seed layer is formed on the surface of the first insulating layer by electroless plating. Next, a mask pattern is formed on the plating seed layer so as to expose a part of the plating seed layer corresponding to a desired wiring pattern. On the exposed plating seed layer, a metal layer is formed by electrolytic plating, and then the mask pattern is removed. Then, the unnecessary plating seed layer is removed by etching or the like, and a conductor layer having a desired wiring pattern can be formed.

The first insulating layer is obtained in step (II), and steps (III) to (V) are performed as necessary, followed by step (VI). Step (VI) is a step of laminating a second resin sheet on the first insulating layer. The lamination of the first insulating layer and the second resin sheet can be performed by the same method as the lamination of the sheet-like support base material and the first resin sheet in the step (I).

However, when the first insulating layer is formed using the sheet-like laminating material, the support of the sheet-like laminate is removed before the step (VI). The removal of the support may be performed between the steps (I) and (II), between the steps (II) and (III), between the steps (III) and (IV), or between the steps (IV) and (V).

After the step (VI), the step (VII) is performed. Step (VII) is a step of curing the second resin sheet to form a second insulating layer. The curing of the second resin sheet can be performed by the same method as the curing of the first resin sheet in the step (II). In this way, a laminated sheet including a plurality of insulating layers such as the first insulating layer and the second insulating layer can be obtained.

In the method according to the above embodiment, (VIII) the step of forming a hole in the second insulating layer, (IX) the step of roughening the second insulating layer, and (X) the step of forming a conductor layer on the second insulating layer may be performed as necessary. The opening of the second insulating layer in the step (VIII) can be performed by the same method as the opening of the first insulating layer in the step (III). In addition, the roughening treatment of the second insulating layer in the step (IX) can be performed by the same method as the roughening treatment of the first insulating layer in the step (IV). The formation of the conductor layer on the second insulating layer in step (X) can be performed by the same method as the formation of the conductor layer on the first insulating layer in step (V).

In the above-described embodiment, the embodiment in which the laminated sheet is produced by laminating and curing 2 resin sheets such as the first resin sheet and the second resin sheet has been described, but the laminated sheet may be produced by laminating and curing 3 or more resin sheets. For example, in the method according to the above-described embodiment, the laminated sheet can be produced by repeating the steps (VI) to (VII) of laminating and curing the resin sheet, and if necessary, the steps (VIII) to (X) of drilling the insulating layer, roughening the insulating layer, and forming the conductor layer on the insulating layer. Thus, a laminated sheet including 3 or more insulating layers can be obtained.

The method according to the above embodiment may include any process other than the above process. For example, when the step (I) is performed, a step of removing the sheet-like support base material may be performed.

< multilayer Flexible substrate >

The multilayer flexible substrate includes a laminated sheet. Accordingly, the multilayer flexible substrate includes an insulating layer formed by curing the resin composition of the present invention. The multilayer flexible substrate may include only the laminated sheet, or may include any member other than the laminated sheet. Examples of the optional member include an electronic component and a cover film (protective film).

The multilayer flexible substrate can be manufactured by a manufacturing method including a method of manufacturing the laminated sheet described above. Therefore, the multilayer flexible substrate can be manufactured by a manufacturing method including (a) a step of preparing a resin sheet and (b) a step of laminating and curing a plurality of resin sheets.

The method for manufacturing a multilayer flexible substrate may include any process other than the above-described process. For example, the method for manufacturing a multilayer flexible substrate including an electronic component may include a step of bonding the electronic component to the laminated sheet. As for the bonding condition between the laminated sheet and the electronic component, any condition can be adopted in which the terminal electrode of the electronic component and the conductor layer provided on the laminated sheet as a wiring can be conductively connected. For example, the method for manufacturing a multilayer flexible substrate provided with a cover film may include a step of laminating a laminated sheet and the cover film.

The multilayer flexible substrate described above can be generally used by being bent so that one surface of a laminated sheet included in the multilayer flexible substrate faces each other. For example, a multilayer flexible substrate is folded to be stored in a case of a semiconductor device in a reduced size. In addition, for example, a multilayer flexible substrate is provided in a semiconductor device having a flexible movable portion in the movable portion.

< semiconductor device >

The semiconductor device includes the multilayer flexible substrate. The semiconductor device includes, for example, a multilayer flexible substrate and a semiconductor chip mounted on the multilayer flexible substrate. In many semiconductor devices, the multilayer flexible substrate may be folded so that one surface of a laminated sheet included in the multilayer flexible substrate faces each other, and stored in a case of the semiconductor device.

Examples of the semiconductor device include various semiconductor devices which can be used in, for example, electric products (for example, computers, mobile phones, digital cameras, televisions, and the like) and vehicles (for example, motorcycles, automobiles, electric trains, ships, airplanes, and the like).

The semiconductor device can be manufactured by a manufacturing method including, for example, a step of preparing a multilayer flexible substrate, a step of bending the multilayer flexible substrate so that one surface of the laminated sheet faces each other, and a step of housing the bent multilayer flexible substrate in a case.

Examples

The present invention will be described in detail with reference to examples. The present invention is not limited by these examples. In the following description, "part" and "%" representing amounts represent "part by mass" and "% by mass", respectively, unless otherwise explicitly stated.

< Synthesis example 1: synthesis of polyimide resin 1

Into a 500ml separable flask equipped with a nitrogen inlet tube and a stirrer were charged 9.13g (30 mmol) of 5-amino-1, 1 '-biphenyl-2-yl 4-aminobenzoate (compound of formula (1')), 15.61g (30 mmol) of 4,4 '- (4, 4' -isopropylidenediphenoxy) diphthalic dianhydride, 94.64g of N-methyl-2-pyrrolidone, 0.47g (6 mmol) of pyridine, and 10g of toluene, and imidization was performed for 4 hours at 180 ℃ while toluene was discharged out of the system, thereby obtaining a polyimide solution containing polyimide resin 1 (nonvolatile content: 20 mass%). In the polyimide solution, no precipitation of the synthesized polyimide resin 1 was observed.

< Synthesis example 2: synthesis of polyimide resin 2

A reaction vessel equipped with a stirrer, a water separator, a thermometer, and a nitrogen gas inlet was charged with 65.0g of aromatic tetracarboxylic dianhydride (BisDA-1000 manufactured by SABIC Japan; 4,4 '- (4, 4' -isopropylidenediphenoxy) diphthalic dianhydride), 266.5g of cyclohexanone, and 44.4g of methylcyclohexane, and the solution was heated to 60 ℃. Then, 43.7g of dimer diamine ("PRIAMINE 1075" manufactured by Croda Japan) and 5.4g of 1, 3-bis (aminomethyl) cyclohexane were added dropwise thereto, and imidization was carried out at 140 ℃ for 1 hour. Thus, a polyimide solution (nonvolatile content: 30% by mass) containing the polyimide resin 2 was obtained. In addition, the weight average molecular weight of the polyimide resin 2 was 25,000.

< Synthesis example 3: synthesis of polyimide resin 3

A500 mL separable flask equipped with a quantitative water content receiver connected to a reflux condenser, a nitrogen gas inlet tube, and a stirrer was prepared. To the flask were added 20.3g of 4, 4' -oxydiphthalic anhydride (ODPA), 200g of gamma-butyrolactone, 20g of toluene, and 29.6g of 5- (4-aminophenoxy) -3- [4- (4-aminophenoxy) phenyl ] -1,1, 3-trimethylindane, and the mixture was stirred at 45 ℃ for 2 hours under a nitrogen stream to effect a reaction. Then, the reaction solution was heated to about 160 ℃ and, while maintaining the temperature, the condensation water was azeotropically removed together with toluene under a nitrogen stream. The "a predetermined amount of water was accumulated in the quantitative water receiver" and "no outflow of water was observed" were checked. After confirmation, the reaction solution was further heated and stirred at 200 ℃ for 1 hour. Then, the mixture was cooled to obtain a polyimide solution (nonvolatile content: 20 mass%) containing a polyimide resin 3 having a 1,1, 3-trimethylindan skeleton. The obtained polyimide resin 3 has a repeating unit represented by the following formula (X1) and a repeating unit represented by the following formula (X2). In addition, the weight average molecular weight of the foregoing polyimide resin 3 was 12,000.

[ chemical formula 10]

[ chemical formula 11]

。

< example 1: preparation of resin composition 1

While stirring, 5 parts of a bicresol-type epoxy resin ("YX 4000 HK" manufactured by mitsubishi chemical corporation, having an epoxy equivalent of about 185), 5 parts of a naphthalene-type epoxy resin ("ESN 475V" manufactured by nyi chemical corporation, having an epoxy equivalent of about 332), 10 parts of a bisphenol AF-type epoxy resin ("YL 7760" manufactured by mitsubishi chemical corporation, having an epoxy equivalent of about 238), and 2 parts of a cyclohexane-type epoxy resin ("ZX 1658 GS" manufactured by mitsubishi chemical corporation, having an epoxy equivalent of about 135) were heated and dissolved in a mixed solvent of 100 parts of the polyimide solution (20 mass% nonvolatile content) obtained in synthesis example 1 and 10 parts of cyclohexanone. After cooling to room temperature, 7.1 parts of a maleimide resin having a biphenyl skeleton (MIR-3000 manufactured by Nippon Chemicals, 70 mass% of toluene as a nonvolatile component: 1 solution of MEK), 4 parts of a cresol novolak-based curing agent having a triazine skeleton (50% of 2-methoxypropanol solution, LA3018-50P, hydroxyl equivalent: 151, active group equivalent: EXB-8000L-65M manufactured by DIC, active group equivalent: 220, 65 mass% of MEK solution as a nonvolatile component), 6 parts of a spherical silica (SC 2500SQ manufactured by Yadu Mar, average particle size: 0.5 μ M, specific surface area: 11.2M) were mixed²(g) silica 100 parts surface-treated with 1 part of N-phenyl-3-aminopropyltrimethoxysilane (KBM 573, product of shin-Etsu chemical Co., Ltd.))50 parts of an amine-based curing accelerator (4-Dimethylaminopyridine (DMAP)) and 0.2 part of a curing accelerator were uniformly dispersed in a high-speed rotary mixer, and then the mixture was filtered through a drum filter ("SHP 020" manufactured by ROKITECHNO) to prepare a resin composition 1.

< example 2: preparation of resin composition 2

A resin composition 2 was prepared in the same manner as in example 1 except that 12.5 parts of a polyphenylmethane maleimide resin ("BMI-2300" manufactured by Daihu chemical industry Co., Ltd., MEK solution having a nonvolatile content of 40% by mass) was used instead of 7.1 parts of a maleimide resin having a biphenyl skeleton ("MIR-3000" manufactured by Nippon chemical industry Co., Ltd., toluene having a nonvolatile content of 70% by mass: 1 solution of MEK) was used.

< example 3: preparation of resin composition 3

A resin composition 3 was prepared in the same manner as in example 1 except that the amount of the maleimide-based resin having a biphenyl skeleton (MIR-3000 manufactured by Nippon chemical Co., Ltd.; toluene having a nonvolatile content of 70% by mass: 1 solution of MEK) used was changed from 7.1 parts to 14.2 parts, and 66.7 parts of the polyimide solution (nonvolatile content of 30% by mass) obtained in Synthesis example 2 was used instead of 100 parts of the polyimide solution (nonvolatile content of 20% by mass) obtained in Synthesis example 1.

< example 4: preparation of resin composition 4

A resin composition 4 was prepared in the same manner as in example 1 except that 100 parts of the polyimide solution (nonvolatile content 20 mass%) obtained in synthesis example 3 was used instead of 100 parts of the polyimide solution (nonvolatile content 20 mass%) obtained in synthesis example 1.

< comparative example 1: preparation of resin composition 5

A resin composition 5 was prepared in the same manner as in example 1 except that 7.1 parts of a maleimide resin having a biphenyl skeleton (MIR-3000 manufactured by Nippon Chemicals, Ltd.; a 1:1 solution of MEK in toluene having a nonvolatile content of 70% by mass) was not used.

Comparative example 2: preparation of resin composition 6

A resin composition 6 was prepared in the same manner as in example 1 except that 12.5 parts of diphenylmethane bismaleimide resin ("BMI 1000" manufactured by Daihe chemical industry Co., Ltd., non-volatile content 40% by mass MEK solution) was used instead of 7.1 parts of maleimide resin having a biphenyl skeleton ("MIR-3000" manufactured by Nippon chemical industry Co., Ltd., non-volatile content 70% by mass toluene: 1 solution of MEK) was used.

< comparative example 3: preparation of resin composition 7

A resin composition 7 was prepared in the same manner as in example 1 except that 66.7 parts of a phenoxy resin ("YX 7553BH 30" manufactured by mitsubishi chemical corporation, solid content 30 mass%) was used instead of the polyimide solution (nonvolatile content 20 mass%) obtained in synthesis example 1.

< measurement of average particle diameter of inorganic Filler >

100mg of the inorganic filler and 10g of methyl ethyl ketone were weighed into a vial, and dispersed for 10 minutes by ultrasonic waves. The particle size distribution of the inorganic filler was measured on a volume basis by a flow cell system using a laser diffraction type particle size distribution measuring apparatus ("LA-960" manufactured by horiba ltd.) with the wavelengths of the light source used being blue and red. From the obtained particle size distribution, the average particle size of the inorganic filler was calculated as a median particle size.

< determination of specific surface area of inorganic Filler >

The specific surface area of the inorganic filler was measured by adsorbing nitrogen gas on the surface of the sample using a BET full-automatic specific surface area measuring apparatus (Macsorb HM-1210, manufactured by Mountech corporation) and calculating the specific surface area by a BET multipoint method.

< test example 1: measurement and evaluation of coefficient of linear thermal expansion in Z direction

The resin compositions of examples and comparative examples were uniformly applied to the release-treated surface of a PET film (thickness: 38 μm) treated with an alkyd resin-based release agent using a die coater so that the thickness of the dried resin composition layer became 50 μm, and dried at 80 to 120 ℃ (average 100 ℃) for 6 minutes to obtain a resin sheet 1.

2 pieces of the obtained resin sheet 1 were prepared and bonded to each other using a batch vacuum press laminator ("MVLP-500" manufactured by Kabushiki Kaisha Co., Ltd.). The lamination was carried out by: after the pressure was reduced to 13hPa or less for 30 seconds, the pressure was bonded for 30 seconds at 120 ℃ and 0.74 MPa. Then, one side of the PET film was peeled off, the resin composition was cured under curing conditions of 190 ℃ for 90 minutes, and then the PET film was peeled off again to obtain a cured product sample having a thickness of 100. mu.m. Further, with respect to the obtained cured product sample, the resin sheets 1 were laminated from both sides, one PET film was peeled off, and cured under the same curing conditions, and then PET was peeled off, thereby obtaining a cured product sample having a thickness of 200 μm. The same operation was repeated until the thickness of the resin became 500. mu.m, to obtain a cured product sample for measuring the linear thermal expansion coefficient.

The obtained cured product sample was cut into 5mm square test pieces, and thermomechanical analysis was performed by a compression load method using a thermomechanical analyzer ("Thermo Plus TMA 8310" manufactured by Rigaku corporation), the samples were loaded on the above-mentioned apparatus, and then measured 2 times continuously under measurement conditions of a load of 1g and a temperature rise rate of 5 ℃/min, and the linear thermal expansion coefficient (ppm) in the Z direction (thickness direction of the cured product sample) which was an average of 25 ℃ to 150 ℃ in the 2 measurements was calculated, and the case where the average of the linear thermal expansion coefficients in the Z direction was less than 60ppm was evaluated as "○", and the case where the average of the linear thermal expansion coefficients in the Z direction was 60ppm or more was evaluated as "x".

< test example 2: evaluation of flexibility (MIT folding endurance)

The resin compositions of examples and comparative examples were uniformly applied to the release-treated surface of a PET film (thickness: 38 μm) treated with an alkyd resin-based release agent using a die coater so that the thickness of the dried resin composition layer became 40 μm, and dried at 80 to 120 ℃ (average 100 ℃) for 6 minutes to obtain a resin sheet 2.

The obtained resin sheet 2 was laminated on a polyimide film (UPILEX S, manufactured by Utsu corporation) using a batch vacuum pressure laminator (MVLP-500, manufactured by Kabushiki Kaisha Co., Ltd.). The lamination was carried out by: after the pressure was reduced to 13hPa or less for 30 seconds, the pressure was bonded for 30 seconds at 120 ℃ and 0.74 MPa. Then, the PET film was peeled off, and the resin composition was cured under curing conditions of 190 ℃ for 90 minutes to peel off the polyimide film, thereby obtaining a cured product sample.

The obtained cured film was cut into test pieces having a width of 15mm and a length of 110mm, and the number of times of folding until breaking of the cured body was measured under the measurement conditions of a load of 2.5N, a bending angle of 90 degrees, a bending radius of 1.0mm, and a bending speed of 175 times/minute in accordance with JIS C-5016 using an MIT tester ("MIT-DA", manufactured by Toyo Seiki Seisaku-Sho Ltd.).

The nonvolatile components and the amounts of the nonvolatile components of the resin compositions of examples and comparative examples, and the measurement results and evaluations of the test examples are shown in table 1 below.

[ Table 1]

。

As is clear from the above results, when a resin composition containing (a) an epoxy resin, (B) a curing agent, and (C) a polyimide resin and (B) a component containing (B-1) a trifunctional or higher maleimide compound is used, a cured product having a low linear thermal expansion coefficient in the Z direction (thickness direction of a cured product sample) and excellent flexibility can be obtained.

Claims (12)

1. A resin composition comprising (A) an epoxy resin, (B) a curing agent and (C) a polyimide resin, wherein the component (B) comprises (B-1) a trifunctional or higher maleimide compound.

2. The resin composition according to claim 1, wherein the component (B-1) is a compound represented by the formula (B1),

wherein X independently represents a single bond or a divalent linking group having 1 to 100 skeleton atoms selected from a carbon atom, an oxygen atom, a sulfur atom and a nitrogen atom, s represents an integer of 1 or more, and a benzene ring B¹、B²And B³Each independently optionally further substituted with 1 to 3 substituents selected from halogen atoms, alkyl groups, alkenyl groups, alkoxy groups and aryl groups.

3. The resin composition according to claim 1, wherein the content of the component (B) is 1 to 40% by mass, based on 100% by mass of nonvolatile components in the resin composition.

4. The resin composition according to claim 1, wherein the mass ratio of the component (B-1) to the component (B) is 10% by mass or more, assuming that the component (B) in the resin composition is 100% by mass.

5. The resin composition according to claim 1, further comprising (D) an inorganic filler or not, wherein the content of the component (D) is 70% by mass or less, assuming that the nonvolatile content in the resin composition is 100% by mass.

6. The resin composition according to claim 1, further comprising (D) an inorganic filler.

7. The resin composition according to claim 1, wherein the linear thermal expansion coefficient in the Z direction at 25 ℃ to 150 ℃ is 100ppm or less.

8. The resin composition according to claim 1, which is used for forming an insulating layer of a multilayer flexible substrate.

9. A cured product of the resin composition according to any one of claims 1 to 8.

10. A resin sheet, comprising:

a support, and

a resin composition layer formed of the resin composition according to any one of claims 1 to 8, provided on the support.

11. A multilayer flexible substrate comprising an insulating layer formed by curing the resin composition according to any one of claims 1 to 8.

12. A semiconductor device comprising the multilayer flexible substrate according to claim 11.