TWI865689B - Adhesive composition, film-like adhesive, adhesive layer, adhesive sheet, copper foil with resin, copper-clad laminate, printed circuit board, and multi-layer circuit board and manufacturing method thereof - Google Patents

Abstract

[Technical Problem] Provide an adhesive composition, a film-like adhesive, an adhesive layer, an adhesive sheet, a copper foil with a resin, a copper-clad laminate, a printed circuit board, and a multi-layer circuit board and a method for manufacturing the same. [Technical means] An adhesive composition, a film-like adhesive, an adhesive layer, an adhesive sheet, a copper foil with a resin, a copper-clad laminate, a printed circuit board, and a multilayer circuit board and a method for manufacturing the same are provided. The adhesive composition comprises: a reaction product (A) of a monomer group containing an acid dianhydride (a1) and a diamine (a2), wherein the acid dianhydride (a1) has an aromatic ring structure and/or an alicyclic structure, and the diamine (a2) contains a dimer diamine; a crosslinking agent (B); and a diene polymer (C); as a monomer constituting the diene polymer (C), a diene monomer having a 1,2-vinyl structure is contained.

Description

Adhesive composition, film-like adhesive, adhesive layer, adhesive sheet, copper foil with resin, copper-clad laminate, printed circuit board, and multi-layer circuit board and manufacturing method thereof

The present invention relates to an adhesive composition, a film-like adhesive, an adhesive layer, an adhesive sheet, a copper foil with resin, a copper-clad laminate, a printed circuit board, and a multi-layer circuit board and a manufacturing method thereof.

In mobile communication devices such as mobile phones and smartphones and their base station devices, network-related electronic equipment such as servers/routers, and large computers, it is necessary to transmit and process large amounts of information with low loss and high speed, and the electrical signals processed by the printed circuit boards of these products are also gradually becoming higher in frequency. However, since high-frequency electrical signals are easily attenuated, it is necessary to further reduce the transmission loss in printed circuit boards. Therefore, the adhesive composition commonly used in printed circuit boards is required to have a low dielectric constant and a low dielectric loss tangent (hereinafter also referred to as low dielectric properties).

In addition, for printed wiring boards, as lead-free strategies for solder materials used when mounting components are progressing, solder heat resistance at a reflow temperature of approximately 260°C is required. In addition, before the reflow step, in order to suppress foaming and expansion caused by moisture absorption, the printed circuit board is mostly pre-dried at a temperature of 100°C to 120°C. Recently, however, in order to improve production efficiency, the reflow step is increasingly performed without performing pre-drying treatment. Therefore, the adhesive used in printed circuit boards is not only required to have adhesiveness, but also to have solder heat resistance.

As an adhesive composition having excellent adhesion and solder heat resistance and low dielectric properties, for example, Patent Document 1 describes a film-like polyimide adhesive having a specified glass transition temperature, tensile fracture strength, and tensile elastic modulus. [Prior Art Document] (Patent Document)

Patent document 1: Japanese Patent Application Publication No. 7-197007

[Technical problem solved by the invention] However, the adhesive shown in Patent Document 1 is insufficient in low dielectric properties in the GHz band, and is an invention that still has room for improvement.

The present disclosure provides an adhesive composition having good adhesion and solder heat resistance and low dielectric properties, a film-like adhesive, an adhesive layer, an adhesive sheet, a copper foil with a resin, a copper-clad laminate, a printed wiring board, and a multi-layer wiring board and a method for manufacturing the same. [Technical means for solving technical problems]

As a result of in-depth research, the inventors found that the above-mentioned problem can be solved by a specific adhesive composition.

According to the present disclosure, the following items are provided. (Item 1) An adhesive composition, comprising: a reaction product (A) of a monomer group containing an acid dianhydride (a1) and a diamine (a2), wherein the acid dianhydride (a1) has an aromatic ring structure and/or an alicyclic structure, and the diamine (a2) contains a dimer diamine; a crosslinking agent (B); and a diene polymer (C); As a monomer constituting the diene polymer (C), a diene monomer having a 1,2-vinyl structure is contained. (Item 2) The adhesive composition as described in Item 1, further comprising a curing agent (D). (Item 3) The adhesive composition as described in Item 1 or 2, further comprising a flame retardant (E). (Item 4) The adhesive composition as described in any one of items 1 to 3, wherein the adhesive composition further comprises a thermal free radical polymerization initiator (F). (Item 5) A film-like adhesive, wherein the film-like adhesive comprises a heat-cured product of the adhesive composition as described in any one of items 1 to 4. (Item 6) An adhesive layer, wherein the adhesive layer comprises the adhesive composition as described in any one of items 1 to 4 or the film-like adhesive as described in item 5. (Item 7) An adhesive sheet, wherein the adhesive sheet comprises the adhesive layer as described in item 6 and a supporting film. (Item 8) A resin-coated copper foil, wherein the resin-coated copper foil comprises the adhesive layer as described in item 6 and a copper foil. (Item 9) A copper-clad laminate, comprising: the adhesive sheet described in Item 7 and/or the copper foil with resin described in Item 8; and one or more selected from the group consisting of copper foil, insulating sheet and supporting film. (Item 10) A printed circuit board, comprising a circuit pattern on the copper foil surface of the copper-clad laminate described in Item 9. (Item 11) A multi-layer circuit board, comprising, in order: a printed circuit board or a printed circuit board (1); the adhesive layer described in Item 6; and a printed circuit board or a printed circuit board (2). (Item 12) A method for manufacturing a multi-layer circuit board, the method comprising the following steps 1 and 2: Step 1: a step of manufacturing a substrate with an adhesive layer by bringing the adhesive composition described in any one of items 1 to 4 or the film-like adhesive described in item 5 into contact with at least one side of a printed circuit board or a printed circuit board (1); Step 2: a step of laminating a printed circuit board or a printed circuit board (2) on the substrate with the adhesive layer, and performing compression bonding under heating and pressure. [Beneficial Effects]

By using the adhesive composition disclosed in the present invention, it is possible to provide an adhesive composition having good adhesiveness and solder heat resistance and low dielectric properties, a film-like adhesive, an adhesive layer, an adhesive sheet, a copper foil with resin, a copper-clad laminate, a printed wiring board, and a multi-layer wiring board and a method for manufacturing the same.

In the entire scope of this disclosure, the range of each physical property value, content, etc. can be appropriately set (for example, selected from the upper and lower limit values recorded in the following items). Specifically, with respect to the numerical value α, when A1, A2, A3, etc. are exemplified as the lower limit of the numerical value α, and B1, B2, B3, etc. are exemplified as the upper limit of the numerical value α, the range of the numerical value α is exemplified as above A1, above A2, above A3, below B1, below B2, below B3, A1~B1, A1~B2, A1~B3, A2~B1, A2~B2, A2~B3, A3~B1, A3~B2, A3~B3, etc. In addition, in this disclosure, "~" is used in the following meaning: including the numerical values recorded before and after it as the lower limit value and the upper limit value.

<Component (A)> The reaction product (A) (hereinafter also referred to as "component (A)") of a monomer group containing an acid dianhydride (a1) (hereinafter also referred to as "component (a1)") having an aromatic ring structure and/or an aliphatic ring structure and a dimeric diamine (a2) (hereinafter also referred to as "component (a2)") disclosed herein refers to polyimide.

<Component (a1)> As component (a1), various known components can be used without particular limitation. The substances listed as components (a1) and substances known as components (a1) can be used alone or in combination of two or more.

As the acid dianhydride having an aromatic ring structure, acid dianhydrides represented by the following general formula are exemplified. (In the formula, X represents a single bond, _-SO2- , -CO-, _-O- , -OC6H4-C( _CH3 ) _{2 - C6H4 -} O-, -COO- _X1 -OCO- or _X2 . _X1 represents -( _CH2 ) _1- (l=1 to 20) or _-H2C -HC(-OC(=O) _-CH3 ) _-CH2- . _X2 represents the following formula. )

Examples of the acid dianhydride having an aromatic ring structure include 3,3',4,4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-diphenylethertetracarboxylic dianhydride, 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride, 2,2-bis(3,3',4,4'-tetracarboxyphenyl)tetrafluoropropane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2'-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2',3,3'-biphenyltetracarboxylic acid dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, pyromellitic acid dianhydride, 1,2,3,4-benzenetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 9,9'-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluorene dianhydride, 9,9'-bis(3,4-dicarboxyphenoxy)fluorene dianhydride, 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride, and the like.

Examples of the acid dianhydride having an alicyclic structure include bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1 , 2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, tetrahydrofuran-2,3,4,5-tetracarboxylic dianhydride, 5-(2,5-dioxotetrahydrofuranyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 5-(2,5-dioxotetrahydrofuranyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, etc.

Examples of the acid dianhydride having an aromatic ring structure and an aliphatic ring structure include the product name "BzDA" (manufactured by JXTG Nippon Energy Co., Ltd.) and the like.

The upper limit of the content of the component (a1) in 100% by mass of the monomer group constituting the component (A) (in terms of solid content) is 80% by mass, 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 10% by mass, 5% by mass, 3% by mass, etc., and the lower limit is 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 10% by mass, 5% by mass, 3% by mass, 1% by mass, etc. In one embodiment, the content of the component (a1) in 100% by mass of the monomer group constituting the component (A) (in terms of solid content) is preferably about 1% by mass to 80% by mass.

<Component (a2)> Component (a2) is a diamine containing a dimer diamine. The dimer diamine is exemplified by a substance obtained by replacing all carboxyl groups of a cyclic or non-cyclic dimer acid obtained as a dimer of an unsaturated fatty acid with primary amine groups. As component (a2), various known components can be used without particular limitation. The substances exemplified as component (a2) and substances known as component (a2) can be used alone, or two or more substances can be used in combination.

As the dimer diamine, the following structures are exemplified. In each formula, m+n is preferably 6 or more and 17 or less, p+q is preferably 8 or more and 19 or less, and the dotted line portion indicates a carbon-carbon single bond or a carbon-carbon double bond.

The dimer diamine may be a commercial product. Examples of such products include "VERSAMINE 551", "VERSAMINE 552 (hydrogenated product of VERSAMINE 551)" (manufactured by Cogniks Japan Co., Ltd.); and "PRIAMINE 1075", "PRIAMINE 1074" (manufactured by CRODA Japan Co., Ltd.).

<Other diamines> In addition to the above-mentioned dimer diamine, the following diamines may be contained in the monomer group of component (A). Examples of diamines other than the above-mentioned dimer diamine include diamines having a alkyl group with a chain structure, diamines having an alicyclic structure, and diamines having an aromatic ring structure.

Examples of the diamine having a chain-structured alkyl group include 1,3-diaminopropane, 1,2-diaminopropane, 1,2-diamino-2-methylpropane, 2,2-dimethyl-1,3-propylenediamine, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, and 1,10-diaminodecane.

Examples of the diamine having an alicyclic structure include 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, and bis(aminomethyl)norbornane.

Examples of the diamine having an aromatic ring structure include 3-aminobenzylamine, 4-aminobenzylamine, 4-(aminomethyl)benzylamine, 2,5-dimethyl-1,4-phenylenediamine, 4,4'-diamino-2,2'-dimethylbibenzyl, 3,3'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, and 1,5-diaminonaphthalene.

In one embodiment, the upper limit of the content of the dimer diamine in 100% by mass of the component (a2) (calculated as solid content) is 100% by mass, 90% by mass, 80% by mass, 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 10% by mass, 5% by mass, etc., and the lower limit is 90% by mass, 80% by mass, 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 10% by mass, 5% by mass, 1% by mass, etc. In one embodiment, the content of the dimer diamine in 100% by mass of the component (a2) (calculated as solid content) is, for example, about 1% by mass to 100% by mass.

In one embodiment, the upper limit of the content of the other diamine in 100% by mass of the component (a2) (calculated as solid content) is 99% by mass, 90% by mass, 80% by mass, 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 10% by mass, 5% by mass, 1% by mass, 0.1% by mass, etc., and the lower limit is 90% by mass, 80% by mass, 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 10% by mass, 5% by mass, 1% by mass, 0.1% by mass, etc. In one embodiment, the content of the other diamine in 100% by mass of the component (a2) (calculated as solid content) is, for example, about 0% by mass to 99% by mass.

Examples of the upper limit of the content (solid content) of the component (a2) in 100% by mass of the monomer group constituting the component (A) are 90% by mass, 85% by mass, 80% by mass, 75% by mass, 70% by mass, 65% by mass, 60% by mass, 55% by mass, 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, and 20% by mass, and examples of the lower limit are 75% by mass, 70% by mass, 65% by mass, 60% by mass, 55% by mass, 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, 20% by mass, and 15% by mass. In one embodiment, the content of the component (a2) in 100% by mass of the monomer group constituting the component (A) (calculated as solid content) is preferably about 15% by mass to 90% by mass.

The upper limit of the weight average molecular weight of the component (A) is 60000, 50000, 40000, 30000, 20000, 10000, 7500, 5500, etc., and the lower limit is 50000, 40000, 30000, 20000, 10000, 7500, 5000, etc. In one embodiment, the weight average molecular weight of the component (A) is preferably about 5000 to 60000 from the viewpoint of dielectric properties, solvent solubility, and softness. In the present disclosure, the weight average molecular weight can be obtained by the polystyrene conversion value measured by gel permeation chromatography (GPC).

In the adhesive composition of the present disclosure, 100% by mass, the upper limit of the content of the component (A) (calculated as solid content) is 99% by mass, 95% by mass, 90% by mass, 80% by mass, 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, etc., and the lower limit is 95% by mass, 90% by mass, 80% by mass, 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, etc. In one embodiment, in the adhesive composition of the present disclosure, 100% by mass, the content of the component (A) (calculated as solid content) is preferably about 20% by mass to 99% by mass.

For the sake of excellent solder heat resistance, the lower limit of the softening point (°C) of the component (A) is 230, 210, 190, 170, 150, 130, 110, 100, 90, 80, 70, etc., and for the sake of excellent workability, the upper limit is 250, 230, 210, 190, 170, 150, 130, 110, 100, 90, 80, etc. In one embodiment, the softening point (°C) of the component (A) is preferably about 70 to 250. In this disclosure, the softening point refers to the intersection of the curve of the storage modulus (G') and the curve of the loss modulus (G") measured using a commercially available measuring instrument (product name "ARES-2KSTD-FCO-STD", manufactured by Rheometric Scientific), that is, the temperature at which tanδ is 1.

The upper limit of the molar ratio of the acid dianhydride to the diamine (acid dianhydride/diamine) is 1.5, 1.4, 1.3, 1.2, 1.1, 1.0, etc., and the lower limit is 1.4, 1.3, 1.2, 1.1, 1.0, 0.9, etc. In one embodiment, the molar ratio of the acid dianhydride to the diamine (acid dianhydride/diamine) is preferably about 0.9 to 1.5 from the viewpoint of solvent solubility and solution stability.

The component (A) can be produced by various known methods. As a method for producing the component (A), there is exemplified a method comprising the following steps: preferably at a temperature of 50°C to 120°C, more preferably at 80°C to 100°C, subjecting a monomer group containing an acid dianhydride having an aromatic ring structure and/or an aliphatic ring structure and a dimer diamine, and further containing other appropriate diamines and other acid anhydrides to an addition polymerization reaction for preferably 5 hours. The step of obtaining an addition polymer is preferably performed at a temperature of 80° C. to 250° C., more preferably 100° C. to 200° C., for preferably 0.5 hour to 50 hours, more preferably 1 hour to 20 hours.

In the imidization reaction, various known reaction catalysts, dehydrating agents, and organic solvents described below can be used. Various known reaction catalysts, dehydrating agents, and organic solvents described below can be used alone or in combination of two or more. Examples of reaction catalysts include aliphatic tertiary amines such as triethylamine; aromatic tertiary amines such as dimethylaniline; heterocyclic tertiary amines such as pyridine, picoline, and isoquinoline. In addition, examples of dehydrating agents include aliphatic anhydrides such as acetic anhydride and aromatic anhydrides such as benzoic anhydride.

The imide ring closure rate of the polyimide is not particularly limited. Here, the "imide ring closure rate" refers to the content of cyclic imide bonds in the polyimide, and can be determined by various spectroscopic methods such as NMR (nuclear magnetic resonance) and IR (infrared) analysis. From the viewpoint of good adhesion and solder heat resistance, the imide ring closure rate of the polyimide is preferably about 70% or more, and more preferably about 85% or more and about 100% or less.

<Crosslinking agent (B)> The crosslinking agent (B) (hereinafter, also referred to as "component (B)") is a substance other than component (C), and any of various known substances can be used without particular limitation as long as it functions as a crosslinking agent for an adhesive. The crosslinking agent may be a substance listed as an example of a crosslinking agent and a substance known as a crosslinking agent alone, or two or more of them may be used in combination. The crosslinking agent is preferably at least one selected from the group consisting of epoxides, benzoxazine, dimaleimide and cyanate.

As the epoxide, various known epoxides can be used without particular limitation. Examples of the epoxide include phenol novolac-type epoxides, cresol novolac-type epoxides, bisphenol A-type epoxides, bisphenol F-type epoxides, bisphenol S-type epoxides, hydrogenated bisphenol A-type epoxides, hydrogenated bisphenol F-type epoxides, stilbene-type epoxides, epoxides containing a triazine skeleton, epoxides containing a fluorene skeleton, linear aliphatic epoxides, alicyclic epoxides, Glycidylamine type epoxides, trisphenolmethane type epoxides, alkyl-modified trisphenolmethane type epoxides, biphenyl type epoxides, epoxides containing a dicyclopentadiene epoxide skeleton, epoxides containing a naphthalene skeleton, arylalkylene type epoxides, tetraglycidylphenylenediamine, dimer acid-modified epoxides which are dimer acid-modified products of the above epoxides, dimer acid diglycidyl esters, etc. The epoxides may also be commercially available products. Examples of such products include "jER828", "jER834", and "jER807" manufactured by Mitsubishi Chemical Corporation; "ST-3000" manufactured by NIPPON STEEL Chemical Co., Ltd.; "CELLOXIDE 2021P" manufactured by DAICEL Co., Ltd.; "YD-172-X75" manufactured by NIPPON STEEL Chemical Co., Ltd.; and "TETRAD-X" manufactured by Mitsubishi Gas Chemical Co., Ltd.

In particular, tetraglycidyl diamine of the following structure has good compatibility with the above-mentioned polyimide. In addition, if this substance is used, the low loss elastic modulus of the adhesive layer becomes easy to be quantified, and its heat-resistant adhesion and low dielectric properties also become good. (Wherein, Y represents a phenylene group or a cyclohexylene group.)

As benzoxazine, various known substances can be used without particular limitation. Examples of benzoxazine include 6,6-(1-methylethylidene)bis(3,4-dihydro-3-phenyl-2H-1,3-benzoxazine) and 6,6-(1-methylethylidene)bis(3,4-dihydro-3-methyl-2H-1,3-benzoxazine). In addition, a phenyl group, a methyl group, a cyclohexyl group, etc. may be bonded to the nitrogen of the oxazine ring. Benzoxazine may also be a commercially available product. Examples of such products include "Benzoxazine F-a type" and "Benzoxazine P-d type" manufactured by Shikoku Chemical Industries, Ltd.; and "RLV-100" manufactured by Air Water Co., Ltd.

As the bismaleimide, various known substances can be used without particular limitation. Examples of the bismaleimide include 4,4'-diphenylmethane bismaleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, 4,4'-diphenyl ether bismaleimide, and 4,4'-diphenylsulfone bismaleimide. Bismaleimide may also be a commercially available product. Examples of such products include "BAF-BMI" manufactured by JFE Chemical Co., Ltd. Since bismaleimide functions not only as a crosslinking agent for polyimide but also as a crosslinking agent for component (C), bismaleimide is a preferred crosslinking agent. In addition, by including bismaleimide in component (B), the crosslinking density is increased, and the adhesiveness and heat resistance of the adhesive composition disclosed in the present invention tend to be better.

As cyanate ester, various known substances can be used without particular limitation. As cyanate ester, 2-allylphenol cyanate, 4-methoxyphenol cyanate, 2,2-bis(4-cyanophenol)-1,1,1,3,3,3-hexafluoropropane, bisphenol A cyanate, diallylbisphenol A cyanate, 4-phenylphenol cyanate, 1,1,1-tris(4-cyanophenyl)ethane, 4-cumylphenol cyanate, 1,1-bis(4-cyanophenyl)ethane, 4,4'-bisphenol cyanate, 2,2-bis(4-cyanophenyl)propane, etc. are exemplified. Cyanate ester may also be a commercially available product. As such a product, "PRIMASET BTP-6020S" manufactured by Lonza Japan Co., Ltd., etc. are exemplified.

The upper limit of the content of the crosslinking agent in 100% by mass of the adhesive composition disclosed herein (calculated as solid content) is 10%, 5%, 2%, 1%, 0.8%, 0.6%, 0.1%, 0.05%, etc., and the lower limit is 5%, 2%, 1%, 0.8%, 0.6%, 0.1%, 0.05%, 0.01%, etc. In one embodiment, the content of the crosslinking agent in 100% by mass of the adhesive composition disclosed herein (calculated as solid content) is preferably about 0.01% to 10% by mass.

<Diene polymer (C)> The diene polymer (C) (hereinafter, also referred to as "component (C)") is a polymer obtained by polymerizing a monomer containing a diene monomer, wherein the diene monomer is a monomer having two carbon-carbon double bonds as polymerizable unsaturated bonds. Component (C) only needs to contain a diene monomer having a 1,2-vinyl structure as a monomer constituting component (C). When only a diene monomer not having a 1,2-vinyl structure is used as a monomer constituting component (C) instead of component (C), the curability of the adhesive composition is poor, and therefore it is not good.

As the component (C), various known components can be used without particular limitation. As the component (C), styrene-butadiene copolymer, polyisoprene, polybutadiene, butadiene-isoprene copolymer, isobutylene-isoprene copolymer, butadiene-acrylonitrile copolymer, styrene-isoprene copolymer, etc. are exemplified. The component (C) may also be a commercially available product. As such a product, liquid butadiene-styrene-random copolymer (product names "RICON100", "RICON181", "RICON184" (manufactured by Cray Valley)); liquid polybutadiene (product names "RICON150", "RICON154", "RICON156" (manufactured by Cray Valley)) and the like are exemplified. The substances exemplified as the component (C) and known substances as the component (C) may be used alone or in combination of two or more.

Component (C) can be produced by various known methods. Examples of the production method of component (C) include: (1) a method of polymerizing a diene monomer (α) having a 1,2-vinyl structure; and (2) a method of copolymerizing a diene monomer (α) having a 1,2-vinyl structure and a monomer (β) that can polymerize with a diene monomer having a 1,2-vinyl structure. In the production of component (C), various polymerization initiators and randomizers may be used as needed. In addition, when component (C) is produced by anionic polymerization using a lithium polymerization initiator, the active end of the polymer chain may be modified with various modifiers. If an olefin oxide such as ethylene oxide is used as a modifier, a diene polymer having a hydroxyl group at both ends or one end may be obtained.

Examples of the diene monomer (α) having a 1,2-vinyl structure include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,4-pentadiene, 2,4-dimethylpenta-1,3-diene, 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, acrylonitrile, divinylbenzene, 1,3-diisopropenylbenzene, and 1,4-diisopropenylbenzene.

Examples of the monomer (β) polymerizable with the diene monomer having a 1,2-vinyl structure include a monomer (β-1) having two or more polymerizable unsaturated bonds and having no 1,2-vinyl structure, and a monomer (β-2) having one polymerizable unsaturated bond.

Examples of the monomer (β-1) having two or more polymerizable unsaturated bonds and not having a 1,2-vinyl structure include 2,3-pentadiene, 2,4-hexadiene, and 2,5-dimethyl-2,4-hexadiene.

Examples of the monomer (β-2) having one polymerizable unsaturated bond include a monomer (β-2-1) having a chain structure and one polymerizable unsaturated bond, and a monomer (β-2-2) having a ring structure and one polymerizable unsaturated bond.

Examples of the monomer (β-2-1) having a chain structure and one polymerizable unsaturated bond include ethylene, propylene, butene, 2-methylpropylene, 3-methyl-1-butene, and 1,3-butadiene monocyclic oxide.

Examples of the monomer (β-2-2) having a cyclic structure and one polymerizable unsaturated bond include a monomer (β-2-2-1) having an aromatic ring structure and one polymerizable unsaturated bond, and a monomer (β-2-2-2) having another cyclic structure and one polymerizable unsaturated bond. Considering that the component (C) tends to have better adhesion, it is preferred to contain a monomer (β-2-2) having a cyclic structure and one polymerizable unsaturated bond, and more preferably, a monomer (β-2-2-1) having an aromatic ring structure and one polymerizable unsaturated bond.

Examples of the monomer (β-2-2-1) having an aromatic ring structure and one polymerizable unsaturated bond include styrene, 3-methylstyrene, 4-methylstyrene, 4-tert-butyl-styrene, and 2-phenyl-1-propene.

Examples of the monomer (β-2-2-2) having another cyclic structure and one polymerizable unsaturated bond include 1,2-epoxy-4-vinylcyclohexane, 1-vinylimidazole, 2-methyl-1-vinylimidazole, vinylcyclopentane, vinylcyclohexane, and 2-vinylpyridine.

The upper limit of the number average molecular weight (Mn) of the component (C) is 20000, 17500, 15000, 12500, 10000, 9000, 8000, 7000, 6000, 5000, 4000, 3000, 2000, etc., and the lower limit is 17500, 15000, 12500, 10000, 9000, 8000, 7000, 6000, 5000, 4000, 3000, 2000, 1000, etc. In one embodiment, the number average molecular weight (Mn) of the component (C) is preferably about 1000 to 20000. When the number average molecular weight (Mn) of the component (C) is less than the upper limit, the adhesion tends to be more excellent. In the present disclosure, the number average molecular weight can be determined from a polystyrene-equivalent value measured by gel permeation chromatography (GPC).

When the monomer (β) polymerizable with the diene monomer having a 1,2-vinyl structure is styrene, the upper limit of the styrene content (styrene mole %) of the component (C) is 60 mol%, 50 mol%, 40 mol%, 30 mol%, 20 mol%, 10 mol%, etc., and the lower limit is 50 mol%, 40 mol%, 30 mol%, 20 mol%, 10 mol%, 5 mol%, etc. In one embodiment, the styrene content (styrene mole %) is preferably about 5 mol% to 60 mol%.

The upper limit of the content of the diene monomer having a 1,2-vinyl structure (1,2vinyl mole %) of the component (C) is 100 mole, 95 mole, 90 mole, 85 mole, 80 mole, 75 mole, 70 mole, 60 mole, 50 mole, 40 mole, 30 mole, 20 mole, etc., and the lower limit is 95 mole, 90 mole, 85 mole, 80 mole, 75 mole, 70 mole, 60 mole, 50 mole, 40 mole, 30 mole, 20 mole, 10 mole, etc. In one embodiment, the 1,2vinyl mole % of the component (C) is preferably about 10 mole % to 100 mole %. The greater the 1,2vinyl mole % of the component (C) in the adhesive composition disclosed herein, the better the adhesion and/or low dielectric properties.

The upper limit of the content of the component (C) in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is 30% by mass, 20% by mass, 10% by mass, 5% by mass, 2% by mass, 1% by mass, etc., and the lower limit is 20% by mass, 10% by mass, 5% by mass, 2% by mass, 1% by mass, 0.5% by mass, etc. In one embodiment, the content of the component (C) in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is preferably about 0.5% by mass to 30% by mass.

<Curing agent (D)> In one embodiment, when component (B) contains an epoxide, various known curing agents (D) (hereinafter also referred to as "component (D)") may be used simultaneously in the adhesive composition of the present disclosure. In the present disclosure, "curing agent" refers to a curing agent that reacts with an epoxide.

As the component (D), various known substances can be used without particular limitation. As the component (D), phenol curing agents, active ester curing agents, amine curing agents, acid anhydride curing agents, imidazole curing agents, etc. are exemplified. The substances exemplified as the component (D) and substances known as the component (D) can be used alone or in combination of two or more.

As the phenolic curing agent, various known substances can be used without particular limitation. Examples of the phenolic curing agent include phenol novolac resin, cresol novolac resin, bisphenol A novolac resin, triazine-modified phenol novolac resin, phosphazene containing phenolic hydroxyl group, etc. The phenolic curing agent may also be a commercially available product. Examples of such products include phosphazenes containing a phenolic hydroxyl group (product name "SPH-100" manufactured by Otsuka Chemical Co., Ltd., etc.), novolac-type phenols ("TD-2091" manufactured by DIC Corporation, "H-4" manufactured by Meiwa Chemicals Co., Ltd.), biphenyl novolac-type phenols ("MEH-7851" manufactured by Meiwa Chemicals Co., Ltd.), aralkyl-type phenol compounds ("MEH-7800" manufactured by Meiwa Chemicals Co., Ltd.), and phenols having an aminotriazine skeleton ("LA1356" and "LA3018-50P" manufactured by DIC Corporation).

As active ester curing agents, various known substances can be used without particular limitation. As active ester curing agents, active ester compounds containing dicyclopentadiene-type diphenol structures, active ester compounds containing naphthalene structures, acetylated active ester curing agents of phenol novolacs, and benzoylated active ester curing agents of phenol novolacs described in Japanese Patent Application Laid-Open No. 2019-183071 are considered. Active ester curing agents can also be commercially available products. As such products, product names such as "EPICLON HPC-8000-65T" and "EXB-8150-65T" (manufactured by DIC Co., Ltd.) are exemplified. Active ester curing agents can be manufactured by various known methods. The active ester curing agent can be obtained by reacting a polyfunctional phenol compound with an aromatic carboxylic acid as described in Japanese Patent No. 5152445.

As the amine curing agent, various known substances can be used without particular limitation. Examples of the amine curing agent include dicyandiamide and aliphatic amines.

As the acid anhydride curing agent, various known substances can be used without particular limitation. Examples of the acid anhydride curing agent include succinic anhydride, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methyl-hexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride, or a mixture of 4-methyl-hexahydrophthalic anhydride and hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl-tetrahydrophthalic anhydride, nadic acid anhydride, methylnadic acid anhydride, norbornane-2,3-dicarboxylic anhydride, methylnorbornane-2,3-dicarboxylic anhydride, methylcyclohexene dicarboxylic anhydride, 3-dodecenyl succinic anhydride, octenyl succinic anhydride, and the like.

As the imidazole curing agent, various known substances can be used without particular limitation. Examples of the imidazole curing agent include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, epoxy-imidazole adducts, and the like.

The upper limit of the content of the component (D) in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is 10%, 5%, 3%, 1%, 0.1%, 0.05%, 0.01%, 0.005%, 0.001%, 0.0005% by mass, etc., and the lower limit is 5%, 3%, 1%, 0.1%, 0.05%, 0.01%, 0.005%, 0.001%, 0.0005%, 0.0001%, 0%, etc. In one embodiment, the content of the component (D) in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is preferably about 0% by mass to about 10% by mass.

When an epoxide and a curing agent are used simultaneously as a crosslinking agent, a reaction catalyst may be used simultaneously. As the reaction catalyst, various known substances may be used without particular limitation. As the reaction catalyst, tertiary amines, imidazoles, organic phosphines, tetraphenyl boron, etc. are exemplified. The substances exemplified as reaction catalysts and substances known as reaction catalysts may be used alone, or two or more substances may be used in combination.

As the tertiary amine, various known substances can be used without particular limitation. Examples of the tertiary amine include 1,8-diazabicyclo[5.4.0]undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol, and the like.

As the imidazoles, various known substances can be used without particular limitation. Examples of the imidazoles include 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, and 2-heptadecylimidazole.

As the organic phosphine, various known substances can be used without particular limitation. Examples of the organic phosphine include tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, and phenylphosphine.

As tetraphenylboron, various known substances can be used without particular limitation. Examples of tetraphenylboron include tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazolium tetraphenylborate, and N-methylmorpholine tetraphenylborate as salts.

The upper limit of the content of the reaction catalyst in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is 5% by mass, 3% by mass, 1% by mass, 0.1% by mass, 0.05% by mass, 0.01% by mass, etc., and the lower limit is 3% by mass, 1% by mass, 0.1% by mass, 0.05% by mass, 0.01% by mass, 0.005% by mass, 0% by mass, etc. In one embodiment, the content of the reaction catalyst in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is preferably about 0% by mass to 5% by mass.

<Flame retardant (E)> In one embodiment, the adhesive composition of the present disclosure may also contain a flame retardant (E) (hereinafter, also referred to as "component (E)"). The substances exemplified as component (E) and substances known as component (E) may be used alone, or two or more substances may be used in combination. Examples of component (E) include phosphorus-based flame retardants, inorganic fillers, and the like.

Examples of phosphorus-based flame retardants (phosphorus-containing flame retardants) include polyphosphoric acid, phosphoric acid esters, and phosphazene derivatives that do not contain a phenolic hydroxyl group. Among the phosphazene derivatives, cyclic phosphazene derivatives are excellent in flame retardancy, heat resistance, and leaching resistance. Examples of commercially available cyclic phosphazene derivatives include SPB-100 manufactured by Otsuka Chemical Co., Ltd. and Rabitle FP-300B manufactured by Fushimi Pharmaceutical Co., Ltd.

Examples of the inorganic filler include silica fillers, phosphorus fillers, fluorine fillers, and inorganic ion exchange fillers. Examples of commercially available inorganic fillers include FB-3SDC manufactured by Denka Co., Ltd., KTL-500F manufactured by Kitamura Co., Ltd., IXE manufactured by Toagosei Co., Ltd., and ADMAFINE SC-2500-SPJ manufactured by Admatechs Co., Ltd. When the inorganic filler as the component (E) is contained, it is particularly preferred because its particle size is 1 μm or less and the laser processability is excellent.

The upper limit of the content of the component (E) in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, 20% by mass, 15% by mass, 10% by mass, 5% by mass, etc., and the lower limit is 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, 20% by mass, 15% by mass, 10% by mass, 5% by mass, 0% by mass, etc. In one embodiment, the content of the component (E) in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is preferably about 0% by mass to 50% by mass.

<Thermal radical polymerization initiator (F)> As the thermal radical polymerization initiator (F) (hereinafter, also referred to as "component (F)"), various known substances can be used without particular limitation. Examples of component (F) include azo compounds and peroxides. The substances exemplified as component (F) and substances known as component (F) can be used alone or in combination of two or more.

Examples of azo compounds that can be used as thermal radical polymerization initiators include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methylbutyronitrile), 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(2-methylpropionamidine) dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, and 2,2'-azobis(2-methylpropionic acid) dimethyl ester.

Examples of peroxides that can be used as thermal radical polymerization initiators include peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxydicarbonate, and peroxyester.

Examples of the peroxyketal include 1,1-di(tertiary hexylperoxy)cyclohexane, 1,1-di(tertiary butylperoxy)cyclohexane, and 2,2-di(tertiary butylperoxy)butane.

Examples of the hydroperoxide include tertiary butyl peroxide, tertiary butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, p-menthane hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide.

Examples of the dialkyl peroxide include dicumyl peroxide, tertiary butylcumyl peroxide, di(tertiary butyl)peroxide, di(tertiary hexyl)peroxide, 2,5-dimethyl-2,5-di(tertiary butylperoxy)hexane, and 2,5-dimethyl-2,5-bis(tertiary butylperoxy)hexane-3.

As the diacyl peroxide, diisobutyl peroxide, di(3,5,5-trimethylhexanoyl) peroxide, dilauryl peroxide, disuccinic acid peroxide, dibenzoyl peroxide, etc. are exemplified. The diacyl peroxide may also be a commercially available product. As such products, product names such as "NYPER BMT-K40" and "NYPER BMT-M" (both manufactured by NOF Corporation) are exemplified.

Examples of the peroxydicarbonate include diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, and di(4-t-butylcyclohexyl)peroxydicarbonate.

Examples of the peroxyester include tertiary butyl peroxypivalate, 2,5-dimethyl-2,5-di(2-ethylhexylperoxy)hexane, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, tertiary hexyl peroxy-2-ethylhexanoate, tertiary butyl peroxy-2-ethylhexanoate, tertiary butyl peroxylaurate, tertiary butyl peroxy-3,5,5-trimethylhexanoate, and tertiary hexylperoxyisopropyl monocarbonate.

The upper limit of the content of the component (F) in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is 5% by mass, 4% by mass, 3% by mass, 2% by mass, 1% by mass, 0.5% by mass, 0.1% by mass, 0.08% by mass, 0.06% by mass, 0.04% by mass, etc., and the lower limit is 4% by mass, 3% by mass, 2% by mass, 1% by mass, 0.5% by mass, 0.1% by mass, 0.08% by mass, 0.06% by mass, 0.04% by mass, 0.01% by mass, 0.005% by mass, 0% by mass, etc. In one embodiment, the content of the component (F) in 100% by mass of the adhesive composition of the present disclosure (calculated as solid content) is preferably about 0% by mass to 5% by mass.

<Organic solvent (G)> In one embodiment, the adhesive composition of the present disclosure may be formulated with an organic solvent (G) (hereinafter, also referred to as "component (G)"). The substances exemplified as component (G) and substances known as component (G) may be used alone, or two or more thereof may be used in combination. Examples of component (G) include ketone solvents, aromatic solvents, alcohol solvents, glycol solvents, glycol ether solvents, ester solvents, halogen solvents, amide solvents, and other petroleum-based solvents.

Examples of the ketone solvent include methyl ethyl ketone, acetylacetone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone.

Examples of aromatic solvents include toluene and xylene; product names include "T-SOL 100" and "T-SOL 150" (both manufactured by JXTG Nippon Energy Co., Ltd.).

Examples of the alcohol solvent include methanol, ethanol, n-propanol, isopropanol, butanol, benzyl alcohol, and cresol.

Examples of the glycol solvent include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, polyethylene glycol, and polypropylene glycol.

Examples of the glycol ether solvent include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-isopropyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-isobutyl ether, ethylene glycol mono-tertiary butyl ether, and bis(2-methoxyethyl) ether.

Examples of the ester solvent include ethyl acetate, butyl acetate, methyl solvent acetate, ethyl solvent acetate, and propylene glycol monomethyl ether acetate.

Examples of the halogen solvent include chloroform and the like.

Examples of the amide solvent include dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, and N-methylcaprolactam.

As other petroleum-based solvents, dimethyl sulfoxide, methylcyclohexane, etc. are exemplified.

The upper limit of the content of the component (G) in 100% by mass of the adhesive composition of the present disclosure is 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 15% by mass, 10% by mass, 5% by mass, etc., and the lower limit is 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 15% by mass, 10% by mass, 5% by mass, 1% by mass, 0% by mass, etc. In one embodiment, the content of the component (G) in 100% by mass of the adhesive composition of the present disclosure is preferably about 0% by mass to 70% by mass.

<Additives> The adhesive composition disclosed herein may contain a substance other than any of the above-mentioned polyimide, crosslinking agent, diene polymer, curing agent, flame retardant, thermal free radical polymerization initiator, and organic solvent as an additive.

Examples of additives include ring-opening esterification reaction catalysts, dehydrating agents, plasticizers, weathering agents, antioxidants, heat stabilizers, lubricants, antistatic agents, whitening agents, coloring agents, conductive agents, mold release agents, surface treatment agents, viscosity regulators, fillers, and the like.

In one embodiment, the content of the additive (calculated as solid content) relative to 100 parts by mass of the adhesive composition is, for example, less than 1 part by mass, less than 0.1 part by mass, less than 0.01 part by mass, or 0 part by mass.

In another embodiment, the content of the additive is, for example, less than 1 part by mass, less than 0.1 part by mass, less than 0.01 part by mass, or 0 part by mass relative to 100 parts by mass (in terms of solid content) of the polyimide.

The adhesive composition disclosed in the present invention can be obtained by dissolving the above-mentioned polyimide, crosslinking agent and diene polymer and, as required, curing agent, flame retardant, thermal free radical polymerization initiator and additive in an organic solvent.

<Film-like adhesive> In the present disclosure, a film-like adhesive is provided, which contains a heat-cured product of the above-mentioned adhesive composition. The method for producing the film-like adhesive is exemplified by a method including the following steps: a step of applying the above-mentioned adhesive composition on a suitable release paper, a step of curing the adhesive composition by volatilizing an organic solvent by heating, and a step of peeling the adhesive composition from the release paper. The thickness of the film-like adhesive is preferably about 3 μm or more and about 40 μm or less. Examples of the release paper include conventionally known release paper, etc.

<Adhesive layer> In the present disclosure, an adhesive layer is provided, the adhesive layer comprising the above-mentioned adhesive composition or the above-mentioned film-like adhesive. When manufacturing the above-mentioned adhesive layer, the above-mentioned adhesive composition and various known adhesives other than the above-mentioned adhesive composition can be used simultaneously. Similarly, the above-mentioned film-like adhesive and various known film-like adhesives other than the above-mentioned film-like adhesive can also be used simultaneously. Furthermore, when manufacturing the above-mentioned adhesive layer, the above-mentioned adhesive composition and various known adhesives (as needed) or the above-mentioned film-like adhesive and various known film-like adhesives (as needed) can be heated and cured to obtain the adhesive layer.

<Adhesive sheet> In the present disclosure, an adhesive sheet is provided, which comprises the above-mentioned adhesive layer and a supporting film.

Examples of the supporting film include plastic films and the like.

Examples of plastics include polyester, polyimide, polyimide-silica mixture, polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polymethyl methacrylate resin, polystyrene resin, polycarbonate resin, acrylonitrile-butadiene-styrene resin, aromatic polyester resin obtained from polyethylene terephthalate, phenol, phthalic acid, hydroxynaphthoic acid, etc., and p-hydroxybenzoic acid (liquid crystal polymer; product name "Vecstar", manufactured by Kuraray Co., Ltd.); cycloolefin polymer; syndiotactic polystyrene resin (SPS); fluororesins (polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), polyvinylidene fluoride (PVDF), etc.), etc. Since the adhesive layer disclosed herein has excellent adhesion, it can also be well adhered and/or closely fitted to a support film that is difficult to adhere to or difficult to fit. The support film that is difficult to adhere to or difficult to fit can be various known materials. Examples of the support film that is difficult to adhere to and/or difficult to fit include liquid crystal polymer (LCP), cycloolefin polymer (COP), syndiotactic polystyrene resin (SPS), fluororesin (PTFE, PFA, PVDF, etc.), etc.

In addition, when the adhesive composition is applied to the support film, various known application methods can be adopted. The thickness of the applied layer after drying is preferably 1 μm or more and 100 μm or less, and more preferably 3 μm or more and 50 μm or less. In addition, the adhesive layer of the adhesive sheet can also be protected by various protective films.

<Copper foil with resin> This disclosure provides a copper foil with resin, which includes the above-mentioned adhesive layer and copper foil. Specifically, the above-mentioned copper foil with resin is formed by applying or bonding the above-mentioned adhesive composition or the above-mentioned film-like adhesive to copper foil. Examples of the copper foil include rolled copper foil and electrolytic copper foil. The thickness of the copper foil is preferably greater than 1μm and less than 100μm, and more preferably greater than 2μm and less than 38μm. In addition, the copper foil may be a copper foil subjected to various surface treatments (roughening, rust prevention, etc.). As the anti-rust treatment, a coating treatment using a coating solution containing Ni, Zn, Sn, etc., a so-called mirror treatment such as a chromate treatment is exemplified. In addition, as the coating method, the aforementioned method is exemplified. The adhesive composition disclosed in the present invention has very good adhesion, so even a material that is difficult to adhere and/or adhere to, such as a copper foil that has been subjected to a mirror treatment, can be well adhered and/or adhered.

The adhesive layer of the copper foil with resin may be uncured, or may be partially cured or fully cured under heating. The partially cured adhesive layer is in the so-called B stage. In addition, the thickness of the adhesive layer is preferably about 0.5 μm or more and 30 μm or less. In addition, the copper foil with resin on both sides may be made by coating or laminating the adhesive layer on both sides of the copper foil.

<Copper clad laminate> In the present disclosure, a copper clad laminate is provided, the copper clad laminate comprising: the above-mentioned adhesive sheet and/or the above-mentioned copper foil with resin; and one or more selected from the group consisting of copper foil, insulating sheet and supporting film. The copper clad laminate is also called CCL (Copper Clad Laminate). Specifically, the copper clad laminate is formed by pressing the above-mentioned copper foil with resin on at least one or both sides of various known copper foils or insulating sheets under heating. In the case of laminating on one side, a material different from the above-mentioned copper foil with resin can also be pressed on the other side. In addition, the number of sheets of the resin-coated copper foil, the copper foil and the insulating sheet in the copper-clad laminate is not particularly limited.

In one embodiment, the insulating sheet is preferably a prepreg or the above-mentioned supporting film. The prepreg is a sheet material (JIS C 5603) in which a resin is impregnated in a reinforcing material such as glass cloth and cured to the B stage. The resin is an insulating resin such as polyimide resin, phenolic resin, epoxy resin, polyester resin, liquid crystal polymer, aromatic polyamide resin, etc. The thickness of the insulating sheet is preferably greater than 20μm and less than 500μm. The heating/pressing conditions are preferably about 150° C. or higher and about 280° C. or lower (more preferably about 170° C. or higher and about 240° C. or lower), and preferably about 0.5 MPa or higher and about 20 MPa or lower (more preferably about 1 MPa or higher and about 8 MPa or lower).

<Printed circuit board> In the present disclosure, a printed circuit board is provided, wherein the printed circuit board has a circuit pattern on the copper foil surface of the copper-clad laminate. As a layout method for forming a circuit pattern on the copper foil surface of the copper-clad laminate, a subtractive method, a semi-additive method, etc. are exemplified. The semi-additive method exemplifies the following method: after forming a pattern on the copper foil surface of the copper-clad laminate with an anti-etching agent film, electrolytic copper plating is performed, the anti-etching agent is removed, and etching is performed with an alkaline solution. In addition, the thickness of the circuit pattern layer in the printed circuit board is not particularly limited. In addition, the printed circuit board can also be used as a core substrate, and the same printed circuit board and other known printed circuit boards or printed circuit boards can be stacked on the core substrate to obtain a multilayer substrate. During the stacking, the above-mentioned adhesive composition and other known adhesives other than the above-mentioned adhesive composition can be used simultaneously. In addition, the number of layers in the multilayer substrate is not particularly limited. In addition, through holes can be inserted and set each time the stacking is performed, and the interior can be plated. The line width/line spacing of the above-mentioned circuit pattern is preferably about 1μm/1μm to 100μm/100μm. In addition, the height of the above-mentioned circuit pattern is preferably about 1μm or more and about 50μm or less.

<Printed circuit board> This disclosure provides a printed circuit board on which various known components such as capacitors are mounted for a printed wiring board.

<Multi-layer circuit board> The present disclosure provides a multi-layer circuit board, which includes, in sequence, a printed circuit board or printed circuit board (1), the above-mentioned adhesive layer, and a printed circuit board or printed circuit board (2). The printed circuit boards of (1) and (2) may also be the above-mentioned printed circuit boards, and may also be various known printed circuit boards. Similarly, the printed circuit boards of (1) and (2) may be the above-mentioned printed circuit boards, and may also be various known printed circuit boards. In addition, the printed circuit boards of (1) and (2) may be the same or different. Similarly, the printed circuit boards of (1) and (2) may be the same or different.

<Manufacturing method of multi-layer circuit board> The present disclosure provides a manufacturing method of a multi-layer circuit board, the method comprising the following steps 1 and 2: Step 1: a step of manufacturing a substrate with an adhesive layer by bringing the above-mentioned adhesive composition or the above-mentioned film-like adhesive into contact with at least one side of a printed circuit board or a printed circuit board (1); Step 2: a step of laminating a printed circuit board or a printed circuit board (2) on the substrate with the adhesive layer and performing compression bonding under heating and pressure.

The printed circuit boards of (1) and (2) above may be the above-mentioned printed circuit boards, or various known printed circuit boards. Similarly, the printed circuit boards of (1) and (2) above may be the above-mentioned printed circuit boards, or various known printed circuit boards.

As a method for bringing the above-mentioned adhesive composition or the above-mentioned film-like adhesive into contact with at least one surface of a printed circuit board or a printed circuit board (1), various known coating methods (curtain coater, roll coater, laminating machine, pressing machine, etc.) are exemplified.

The heating temperature and pressing time after laminating the printed circuit board or printed circuit board (2) on the substrate with the adhesive layer are preferably as follows: (a) after the adhesive composition or film-like adhesive disclosed in the present invention is contacted with at least one surface of the core substrate, it is heated at about 70°C to about 200°C for about 1 minute to about 10 minutes to about 10 minutes to carry out a curing reaction; (b) then further heat-treated at about 150°C to about 250°C for about 10 minutes to about 3 hours to carry out a curing reaction of the crosslinking agent. In addition, the pressure in the entire steps (a) and (b) is preferably 0.5MPa to about 20MPa, and more preferably 1MPa to about 8MPa. [Example]

Below, enumerate manufacturing example, comparative manufacturing example, embodiment, comparative example, evaluation example and comparative evaluation example, further specifically describe the present invention, but the present invention is not limited to these embodiments.In addition, in the following description, as long as not subject to special description, then "part" and "%" are quality standards.

In this embodiment, the weight average molecular weight (Mw) is measured by gel permeation chromatography (GPC) under the following conditions. (GPC measurement conditions) Model: Product name "HLC-8320GPC" (manufactured by Tosoh Corporation) Column: Product name "TSKgel SuperHZM-M" (manufactured by Tosoh Corporation) Developing solvent: THF Flow rate: 0.35 mL/min Measurement temperature: 40°C Detector: RI Standard: Polystyrene Sample preparation: 0.4% solution

<Production Example 1: Production of polyimide (A-1)> In a reaction vessel equipped with a stirrer, a water separator, a thermometer, and a nitrogen gas conduit, 100.00 g of 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride (product name "BisDA-1000" (hereinafter, also referred to as "BisDA"), manufactured by SABIC Innovative Plastics Japan Co., Ltd.) and 371.82 g of cyclohexanone were added, and the solution was heated to 60°C. Next, 100.82 g of C36 dimer diamine (product name "PRIAMINE1075", manufactured by CRODA Japan Co., Ltd.) was slowly added, and then 74.36 g of methylcyclohexane was added, and the mixture was heated to 140°C and imidization reaction was carried out for 3 hours to obtain a solution of polyimide (A-1) (non-volatile component 30.0%). The polyimide resin had an acid component/amine component molar ratio of 1.03, a softening point of 80°C, and a weight average molecular weight of 40,000.

<Production Example 2: Production of polyimide (A-2)> In a reaction vessel equipped with a stirrer, a water separator, a thermometer, and a nitrogen gas conduit, 100.00 g of BisDA and 275.00 g of cyclohexanone were added, and the solution was heated to 60°C. Next, 67.25 g of C36 dimer diamine (product name "PRIAMINE1075", manufactured by CRODA Japan Co., Ltd.) and 8.34 g of 1,3-bis(aminomethyl)cyclohexane (product name "1,3-BAC", manufactured by Mitsubishi Gas Chemical Co., Ltd.) were slowly added, and then 45.83 g of methylcyclohexane and 82.50 g of ethylene glycol dimethyl ether (DMG) were added, and the mixture was heated to 140° C. and imidization reaction was carried out for 3 hours to obtain a solution of polyimide (A-2) (non-volatile component 30.0%). The polyimide resin had an acid component/amine component molar ratio of 1.05, a softening point of 100° C., and a weight average molecular weight of 30,000.

<Production Example 3~Production Example 4: Production of polyimide (A-3)~(A-4)> Production Example 3~Production Example 4 were carried out in the same manner as Production Example 1, except that the composition was changed to the content of Table 1, to obtain polyimide (A-3)~(A-4).

[Table 1] Manufacturing Example 1 Manufacturing Example 2 Manufacturing Example 3 Manufacturing Example 4 Acid dianhydride BisDA 100.00 100.00 100.00 - BTDA - - - 100.00 Diamine PRIAMINE1075 100.82 67.25 95.27 162.70 1,3-BAC - 8.34 - - Organic solvents Cyclohexanone 371.82 275.00 362.0 480.60 Methylcyclohexane 74.36 45.83 72.4 96.12 DMG - 82.50 - - Properties of polyimide Softening point(℃) 80 100 80 80 Acid component/amine component 1.03 1.05 1.09 1.03 Weight average molecular weight 40000 30000 26000 35000 Solid content (%) 30.0 30.0 30.0 30.0

The meanings of the terms in the above table are as follows. BisDA: 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride (manufactured by SABIC Innovative Plastics Japan Co., Ltd.) BTDA: 3,3',4,4'-benzophenonetetracarboxylic dianhydride PRIAMINE1075: C36 dimer diamine (manufactured by CRODA Japan Co., Ltd.) 1,3-BAC: 1,3-bis(aminomethyl)cyclohexane (manufactured by Mitsubishi Gas Chemical Co., Ltd.) DMG: ethylene glycol dimethyl ether

<Example 1: Preparation of adhesive composition (1)> 100.0 g of a solution of polyimide (A-1), 0.93 g of a multifunctional epoxy resin (product name "TETRAD-X", manufactured by Mitsubishi Gas Chemical Co., Ltd.) as a crosslinking agent (B), 3.40 g of a liquid butadiene-styrene-random copolymer (product name "Ricon 100", manufactured by Cray Valley Co., Ltd.) as a diene polymer (C), and 2-ethyl-4-methylimidazole (product name "CUREZOL 2E4MZ-A", manufactured by Shikoku Chemicals Co., Ltd.), 0.0032 g of spherical silica filler (product name "FB-3SDC", manufactured by Denka Co., Ltd.) as a flame retardant (E), 19.64 g of a methyl ethyl ketone dispersion (solid content 50%) of a phosphorus flame retardant (product name "Exolit OP935", manufactured by Clarion Chemicals Co., Ltd.) as a methyl ethyl ketone dispersion (solid content 40%), and 0.034 g of dicumyl peroxide (product name "PERCUMYL D", manufactured by NOF Corporation) as a thermal radical polymerization initiator (F) were mixed, and the mixture was sufficiently stirred with 27.38 g of cyclohexanone as an organic solvent (G) to obtain an adhesive composition having a non-volatile component content of 30.0%.

<Example 2 to Example 22 and Comparative Example 1 to Comparative Example 3: Preparation of adhesive compositions (2) to (22) and (C1) to (C3)> Example 2 to Example 22 and Comparative Example 1 to Comparative Example 3 were carried out in the same manner as Example 1, except that the composition of the adhesive composition was changed to the contents of Table 2 to Table 4, to obtain adhesive compositions (2) to (22) and (C1) to (C3) having a non-volatile component content of 30%.

<Evaluation Example 1-1: Preparation of copper-clad laminate (1)> The adhesive composition (1) was applied to a release film (product name "WH52-P25CM (white)", manufactured by Sun A Chemical Research Co., Ltd.) using a gap coater to a thickness of 25 μm after drying, and then dried at 150°C for 5 minutes. The film-like adhesive is peeled off from the release film, and one side of the obtained film-like adhesive is laminated on the mirror side of a commercially available electrolytic copper foil (product name "F2-WS", manufactured by Furukawa Electric Co., Ltd.) (film thickness 18μm), and the other side is laminated on a commercially available LCP film (product name "Vecstar", manufactured by Kuraray Co., Ltd.) to produce a laminate of LCP film-film-like adhesive-electrolytic copper foil. Then, the laminate is placed on a support for pressing, and heated and pressed from the electrolytic copper foil side under a pressure of 2.5MPa, 180°C, and for 90 minutes to produce a 10cm×10cm copper-clad laminate (1).

<Evaluation Example 1-2 to Evaluation Example 1-10 and Comparative Evaluation Example 1-1 to Comparative Evaluation Example 1-2: Preparation of copper-clad laminates (2) to (10) and (C1) to (C2)> Except that the adhesive composition (1) was changed to the adhesive composition (2) to (10) or (C1) to (C2), Evaluation Example 1-2 to Evaluation Example 1-10 and Comparative Evaluation Example 1-1 to Comparative Evaluation Example 1-2 were performed in the same manner as Evaluation Example 1-1 to obtain copper-clad laminates (2) to (10) and (C1) to (C2).

<Evaluation Example 2-1: Preparation of multi-layer circuit board (1)> The adhesive composition (6) was applied to a release film (product name "WH52-P25CM (white)", manufactured by Sun A Chemical Research Co., Ltd.) using a gap coater so that the thickness after drying was 25 μm, and then dried at 150°C for 5 minutes. The film-like adhesive is peeled off from the release film, and one side of the obtained film-like adhesive is laminated on the copper foil side of a commercially available flexible copper-clad laminate (product name "2NUSR2518LJ1", manufactured by Kunshan Yasen Electronic Materials Technology Co., Ltd., PI: 1 mil, Cu: 1/2 ounce), and the other side of the film-like adhesive is laminated on the polyimide side of another flexible copper-clad laminate (product name "2NUSR2518LJ1") to produce a laminate of a flexible copper-clad laminate-film-like adhesive-flexible copper-clad laminate. Next, the laminate was placed on a support for pressing and heated and pressed under conditions of a pressure of 2.5 MPa, 180°C and 90 minutes to produce a 10 cm x 10 cm multilayer circuit board (1). In addition, since there was no circuit pattern on the copper foil surface of the above-mentioned flexible copper-clad laminate, it strictly does not meet the definition of the multilayer circuit board disclosed in the present disclosure. That is, the multilayer circuit board (1) was produced as a virtual model of the multilayer circuit board.

<Evaluation Example 2-2 to Evaluation Example 2-13 and Comparative Evaluation Example 2-1 to Comparative Evaluation Example 2-2: Preparation of multi-layer circuit boards (2) to (13) and (C1) to (C2)> Except for changing the adhesive composition (6) to the adhesive composition (11) to (22) or (C2) to (C3), Evaluation Example 2-2 to Evaluation Example 2-13 and Comparative Evaluation Example 2-1 to Comparative Evaluation Example 2-2 were performed in the same manner as Evaluation Example 2-1 to obtain multi-layer circuit boards (2) to (13) and (C1) to (C2).

<Performance evaluation (1): Dielectric constant and dielectric loss tangent test> The adhesive compositions (1) to (22) and (C1) to (C3) were applied to a release film (product name "WH52-P25CM (white)", manufactured by Sun A Chemical Research Co., Ltd.) using a gap coater so that the thickness after drying was 25 μm, and then dried at 150°C for 5 minutes. The film-like adhesive was peeled off from the release film, fixed on a Teflon film, and cured at 180°C for 90 minutes. For the obtained samples, the dielectric constant and dielectric loss tangent at 10 GHz were measured by combining a commercially available dielectric constant measuring device (product name "Perturbation Method Sample Hole-Closed Cavity Resonator Method Dielectric Constant/Dielectric Loss Tangent Measurement System", manufactured by KEYCOM Co., Ltd.) and a network analyzer (product name "E8361A", manufactured by Agilent Technologies Co., Ltd.) according to the perturbation method cavity resonator method. The measurement results are shown in Tables 2 to 4.

<Performance evaluation (2): Adhesion test> For the various copper-clad laminates described in the above evaluation example 1 and the various multilayer circuit boards described in the above evaluation example 2, the peel strength (N/cm) was measured in accordance with JIS C 6481 (Test methods for copper-clad laminates for printed circuit boards). The measurement results are shown in Tables 2 to 4.

<Performance evaluation (3): Solder heat resistance test> For the various copper-clad laminates described in the above evaluation example 1 and the various multi-layer circuit boards described in the above evaluation example 2, the samples that had just been cured and left at a temperature of 25°C and a humidity of 25% for 24 hours were floated in a 288°C solder bath with the copper foil side facing downward for 30 seconds. After being removed from the solder bath, the appearance changes were evaluated according to the following criteria. The measurement results are shown in Tables 2 to 4. 0: No change on the copper-clad laminate 4cm×4cm ×: Bubbling was visible on the entire surface of the copper-clad laminate 4cm×4cm

[Table 2]

[Table 3]

[Table 4] Comparison Example 1 Comparison Example 2 Comparison Example 3 (A) Polyimide (A-1) - 100.0 - Polyimide (A-2) - - 80.0 Polyimide (A-3) - - 20.0 Polyimide (A-4) 100.0 - - (B) TETRAD-X 0.93 0.28 0.48 BMI-3000H - - - BMI-1000H - - - (C) Ricon-100 - - - Ricon-181 - - - Ricon-184 - - - Ricon-150 - - - Ricon-154 - - - (D) 2E4MZ-A 0.0032 0.0032 0.0054 HPC-8000-65T - 0.99 1.69 (E) FB-3SDC 19.64 19.64 20.05 Exolit OP935 12.27 12.27 12.53 (F) PERCUMYL D - - - PERHEXA 25B - - - PERMENTA H - - - (G) Cyclohexanone 19.36 19.01 20.65 Dielectric constant/ Dielectric loss tangent 2.4/0.0025 2.5/0.0022 2.4/0.0017 LCP peel strength 0.5 0.2 - PI peel strength - 0.8 0.5 Solder heat resistance (LCP) ０/０ ×/× - Solder heat resistance (PI) - ×/× ０/０

The meanings of the terms in the above table are as follows. TETRAD-X: Multifunctional epoxy resin (manufactured by Mitsubishi Gas Chemical Co., Ltd.) BMI-3000H: Metaphenylene bismaleimide (manufactured by Yamato Chemical Co., Ltd.) BMI-1000H: 4,4'-diphenylmethane bismaleimide (manufactured by Yamato Chemical Co., Ltd.) BMI-2300: Polyphenylmethane maleimide (manufactured by Yamato Chemical Co., Ltd.) Ricon-100: Liquid butadiene-styrene-random copolymer (number average molecular weight: 4500, 1,2vinyl mol%: 70 mol%, styrene content: 25 mol%, CRAY Ricon-181: Liquid butadiene-styrene-random copolymer (number average molecular weight: 3200, 1,2vinyl mole %: 30 mole %, styrene content: 28 mole %, manufactured by CRAY VALLEY) Ricon-184: Liquid butadiene-styrene-random copolymer (number average molecular weight: 8600, 1,2vinyl mole %: 30 mole %, styrene content: 28 mole %, manufactured by CRAY VALLEY) Ricon-150: Liquid polybutadiene (number average molecular weight: 3900, 1,2vinyl mole %: 70 mole %, manufactured by CRAY VALLEY) Ricon-154: Liquid polybutadiene (number average molecular weight: 5200, 1,2vinyl mole %: 90 mole %, CRAY =VALLEY Co., Ltd.) 2E4MZ-A: 2-ethyl-4-methylimidazole (product name: CUREZOL 2E4MZ-A, manufactured by Shikoku Chemical Industries, Ltd.) HPC-8000: Active ester resin (product name "EPICLON HPC-8000-65T", manufactured by DIC Co., Ltd., solid content 65%) FB-3SDC: Spherical silica filler with an average particle size of 3μm (manufactured by Denka Co., Ltd.) (50% dispersion) Exolit OP935: Phosphorus flame retardant (manufactured by CLARIANT Chemicals Co., Ltd.) (40% dispersion) SC-2500-SPJ: Surface-modified spherical silica with an average particle size of 0.5μm (manufactured by Admatechs Co., Ltd.) PERCUMYL D: Dicumyl peroxide (manufactured by NOF Corporation) PERHEXA 25B: 2,5-dimethyl-2,5-di(tertiary butylperoxy)hexane (manufactured by NOF Corporation) PERMENTA H: p-Menthane hydroperoxide (manufactured by NOF Corporation)

Domestic storage information (please note in the order of storage institution, date, and number) None Foreign storage information (please note in the order of storage country, institution, date, and number) None

Claims (12)

An adhesive composition, comprising: a reaction product (A) of a monomer group containing an acid dianhydride (a1) and a diamine (a2), wherein the acid dianhydride (a1) has an aromatic ring structure and/or an alicyclic structure, and the diamine (a2) contains a dimer diamine; a crosslinking agent (B); and a diene polymer (C); as a monomer constituting the diene polymer (C), a diene monomer having a 1,2-vinyl structure is contained; the diene monomer having a 1,2-vinyl structure is selected from 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, At least one of the group consisting of 1,3-pentadiene, 1,4-pentadiene, 2,4-dimethylpenta-1,3-diene, 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, acrylonitrile, divinylbenzene, 1,3-diisopropenylbenzene and 1,4-diisopropenylbenzene; the number average molecular weight (Mn) of the diene polymer is 1000-20000; the content ratio of component (A), component (B) and component (C) is (A) component: (B) component: (C) component = 20-99: 0.01-10: 0.5-30 in terms of mass ratio based on solid content conversion. The adhesive composition as described in claim 1, wherein the adhesive composition further comprises a curing agent (D). The adhesive composition as described in claim 1 or 2, wherein the adhesive composition further comprises a flame retardant (E). The adhesive composition as described in claim 1 or 2, wherein the adhesive composition further comprises a thermal free radical polymerization initiator (F). A film-like adhesive, the film-like adhesive comprising a heat-cured product of the adhesive composition described in any one of claims 1 to 4. An adhesive layer, the adhesive layer comprising the adhesive composition described in any one of claims 1 to 4 or the film-like adhesive described in claim 5. An adhesive sheet comprising the adhesive layer and a supporting film as described in claim 6. A resin-coated copper foil, the resin-coated copper foil comprising the adhesive layer and copper foil as described in claim 6. A copper-clad laminate, comprising: the adhesive sheet described in claim 7 and/or the copper foil with resin described in claim 8; and one or more selected from the group consisting of copper foil, insulating sheet and supporting film. A printed circuit board having a circuit pattern on the copper foil surface of the copper-clad laminate described in claim 9. A multi-layer circuit board, the multi-layer circuit board comprising in sequence: a printed circuit board or a printed circuit board (1); the adhesive layer described in claim 6; and a printed circuit board or a printed circuit board (2). A method for manufacturing a multi-layer circuit board, the method comprising the following steps 1 and 2: Step 1: a step of manufacturing a substrate with an adhesive layer by bringing the adhesive composition described in any one of claims 1 to 4 or the film-like adhesive described in claim 5 into contact with at least one side of a printed circuit board or a printed circuit board (1); Step 2: a step of laminating a printed circuit board or a printed circuit board (2) on the substrate with the adhesive layer, and performing compression bonding under heating and pressure.