JP2022132145A - Adhesive composition, cured product, adhesive sheet, copper foil with resin, copper-clad laminate, and printed wiring board - Google Patents

Abstract

To provide an adhesive composition which gives an adhesive composition layer achieving both a low dielectric constant and a low dielectric loss tangent.SOLUTION: The present invention relates to: an adhesive composition which contains a polyimide (A) being a reaction product of a monomer group including an aromatic tetracarboxylic acid anhydride (a1) and a diamine (a2) containing a dimer diamine, a liquid crystal polymer filler (B), and also a crosslinking agent (C); a cured product of the composition; and an adhesive sheet, a copper foil with resin, a copper-clad laminate, and a printed wiring board including the cured product.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to an adhesive composition, a cured product, an adhesive sheet, a resin-coated copper foil, a copper-clad laminate, and a printed wiring board.

Flexible printed wiring boards (FPWB: Flexible Printed Wiring Board), printed circuit boards (PCB: Printed Circuit Board), and multilayer wiring boards using them are used in mobile communication devices such as mobile phones and smart phones, base station devices thereof, and servers.・It is widely used in products such as network-related electronic devices such as routers and large computers.

In recent years, these products use high-frequency electrical signals to transmit and process large amounts of information at high speed. It is necessary to devise ways to reduce losses as much as possible.

As a means for suppressing transmission loss in a multilayer wiring board, for example, when laminating a printed wiring board or a printed circuit board, an adhesive having a property that both the dielectric constant and the dielectric loss tangent are small (hereinafter also referred to as low dielectric property) Compositions are contemplated that include polyimide resins.

As such an adhesive composition, a thermosetting resin, a flame retardant, and an organic solvent are blended with a polyimide resin obtained by reacting diamines containing 30 mol % or more of aromatic tetracarboxylic acids and dimer diamine. It is publicly known (Patent Document 1). However, the adhesive composition may have a high dielectric loss tangent.

In addition, as a technique for lowering the dielectric loss tangent, for example, a resin composition for adhesives in which an inorganic filler such as fused silica is added to a polyimide resin is also known (Patent Document 2). In this case, the dielectric constant was increased, and the compatibility between low dielectric properties was insufficient.

JP 2013-199645 A JP 2016-041797 A

An object of the present invention is to provide an adhesive composition that provides an adhesive composition layer (hereinafter also referred to as "adhesive layer") that achieves both a low dielectric constant and a low dielectric loss tangent.

Means for Solving the Problems As a result of intensive studies in order to solve the above problems, the present inventors have found that an adhesive composition containing a specific filler can solve the above problems, and have completed the present invention. That is, the present invention provides the following.

1. An adhesive composition comprising a polyimide (A) which is a reactant of a monomer group containing an aromatic tetracarboxylic anhydride (a1) and a diamine (a2) containing a dimer diamine, and a liquid crystal polymer filler (B).

2. 2. The adhesive composition according to item 1, wherein the component (a2) further contains an alicyclic diamine and/or an aromatic diamine.

3. 3. The adhesive composition according to item 1 or 2 above, wherein the content of component (B) is 20 to 300 parts by weight in terms of non-volatile content per 100 parts by weight of component (A).

4. 4. The adhesive composition according to any one of the preceding items 1 to 3, further comprising a cross-linking agent (C).

5. 5. The adhesive composition according to any one of items 1 to 4, wherein the content of component (C) is 1 to 20 parts by weight in terms of non-volatile content per 100 parts by weight of component (A).

6. A cured product of the adhesive composition according to any one of 1 to 5 above.

7. 7. An adhesive sheet having the cured product as described in 6 above on at least one side of a support film.

8. A resin-coated copper foil comprising the cured product according to 6 above and a copper foil.

9. 9. A copper-clad laminate comprising the resin-coated copper foil according to 8 above, and the copper foil or the insulating sheet.

10. 10. A printed wiring board having a circuit pattern on the copper foil surface of the copper-clad laminate according to 9 above.

The adhesive composition of the present invention achieves both a low dielectric constant and a low dielectric loss tangent.

The adhesive composition of the present invention contains an aromatic tetracarboxylic anhydride (a1) (hereinafter referred to as component (a1)) and a diamine (a2) containing dimer diamine (hereinafter referred to as component (a2)). It contains polyimide (A) (hereinafter referred to as component (A)), which is a reactant of the monomer group, and liquid crystal polymer filler (B) (hereinafter referred to as component (B)).

Component (A) is polyimide and is used for the adhesive layer to exhibit a low dielectric constant and a low dielectric loss tangent.

Component (a1) is not particularly limited, and examples include 2,2′,3,3′-biphenyltetracarboxylic dianhydride, 2,3′,3,4′-biphenyltetracarboxylic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, pyromellitic dianhydride, 1,2,3,4-benzenetetracarboxylic anhydride, 3,3′,4,4′- Diphenylsulfonetetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 4,4'-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride, 2,2 ',3,3'-benzophenonetetracarboxylic dianhydride, 2,3,3',4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride , 2,3′,3,4′-diphenyl ether tetracarboxylic dianhydride, bis(2,3-dicarboxyphenyl)ether dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, bis (3,4-dicarboxyphenyl)methane dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, bis(2,3-dicarboxyphenoxyphenyl) ) sulfone dianhydride, bis(3,4-dicarboxyphenoxyphenyl) sulfone dianhydride, 1,4,5,8-naphthalenetetracarboxylic anhydride, 2,3,6,7-naphthalenetetracarboxylic anhydride 2,3,6,7-anthracenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic acid dianhydride Anhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 2,2-bis(3,3′,4,4′-tetracarboxyphenyl)tetrafluoropropane dianhydride etc. These may be used alone or in combination of two or more.

（式（１）中、Ｘは単結合、－ＳＯ_２－、－ＣＯ－、－Ｏ－、－Ｏ－Ｃ_６Ｈ_４－Ｃ（ＣＨ_３）_２－Ｃ_６Ｈ_４－Ｏ－、－Ｃ（ＣＨ_３）_２－、－Ｏ－Ｃ_６Ｈ_４－ＳＯ_２－Ｃ_６Ｈ_４－Ｏ－、－Ｃ（ＣＨＦ₂）_２－、－Ｃ（ＣＦ_３）_２－、－ＣＯＯ－（ＣＨ_２）_ｐ－ＯＣＯ－、又は－ＣＯＯ－Ｈ_２Ｃ－ＨＣ（－Ｏ－Ｃ（＝Ｏ）－ＣＨ_３）－ＣＨ_２－ＯＣＯ－を表し、ｐは１～２０の整数を表す。） Among them, the component (a1) is preferably represented by the following general formula (1) from the viewpoint of flexibility of the adhesive layer and resistance to soldering heat.

(In formula (1), X is a single bond, —SO ₂ —, —CO—, —O—, —OC ₆ H ₄ —C(CH ₃ ) ₂ —C ₆ H ₄ —O—, —C (CH ₃ ) ₂ —, —O—C ₆ H ₄ —SO ₂ —C ₆ H ₄ —O—, —C(CHF ₂ ) ₂ —, —C(CF ₃ ) ₂ —, —COO—(CH ₂ ) _p -OCO- or -COO-H ₂ C-HC(-OC(=O)-CH ₃ )-CH ₂ -OCO-, p represents an integer of 1 to 20.)

Examples of those represented by the general formula (1) include 2,2′,3,3′-biphenyltetracarboxylic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, 3,3′,4,4′-diphenyl ether tetracarboxylic acid acid dianhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 2,2-bis(3,3',4,4'-tetracarboxyphenyl)tetrafluoropropane anhydride, 4,4′-[propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2'-bis(3,4-dicarboxyphenoxyphenyl)sulfone dianhydride and the like. These may be used alone or in combination of two or more. Among them, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 4,4'-[propane-2,2 -diylbis(1,4-phenyleneoxy)]diphthalic dianhydride is preferred.

The amount of component (a1) used in 100 mol % of the monomer group constituting component (A) is not particularly limited, and is usually 10 to 90 mol %, preferably 25 to 75 mol %.

In addition, the amount of the tetracarboxylic anhydride represented by the general formula (1) in 100 mol% of the monomer group constituting the component (A) is not particularly limited, and is usually 10 to 90 mol%, preferably , from 25 to 75 mol %.

The amount of the tetracarboxylic acid anhydride represented by the general formula (1) used in 100 mol % of component (a1) is not particularly limited, and is usually 10 to 100 mol %, preferably 50 to 100 mol %. be.

The (a2) component is a diamine including dimer diamine.

A dimer diamine is a dimer acid in which all the carboxyl groups are substituted with primary amino groups or primary aminomethyl groups (see, for example, JP-A-9-12712). Here, the dimer acid mainly contains a dibasic acid having 36 carbon atoms obtained by dimerizing unsaturated fatty acids such as oleic acid, linoleic acid and linolenic acid. It contains 18 monomer acids, 54 carbon trimer acids, and 20-90 carbon polymerized fatty acids. Although the dimer acid contains a double bond, the degree of unsaturation may be reduced by, for example, a hydrogenation reaction.

The dimer diamine is not particularly limited, and examples thereof include those represented by the following general formula (2). In general formula (2), m+n=6 to 17 is preferable, p+q=8 to 19 is preferable, and the dashed line means a carbon-carbon single bond or a carbon-carbon double bond.

Commercially available dimer diamines include "Versamin 551", "Versamin 552" (manufactured by Cognix Japan Co., Ltd.), "PRIAMINE 1073", "PRIAMINE 1074", and "PRIAMINE 1075" (manufactured by Croda Japan Co., Ltd.). made) and the like.

The dimer diamine may contain amines derived from the monomer acid, trimer acid and/or polymerized fatty acid, and the content thereof is 10% by weight or less, preferably 5% by weight or less in the dimer diamine. It is more preferably 3% by weight or less, still more preferably 2% by weight or less.

Further, the dimer diamine may be used as a commercially available product as it is, or may be used after being purified by distillation or the like.

The amount of dimer diamine to be used in 100 mol % of the monomer group constituting component (A) is not particularly limited, and is usually 5 mol % or more, preferably 25 to 75 mol %.

The amount of dimer diamine used in 100 mol % of component (a2) is not particularly limited, and is usually 10 mol % or more, preferably 30 to 100 mol %.

The component (a2) may also contain a diamine (a2-1) (hereinafter referred to as component (a2-1)) other than dimer diamine. Component (a2-1) may include, for example, aliphatic diamines, alicyclic diamines, aromatic diamines, diaminoethers, and diaminopolysiloxanes. These amines exclude dimer diamines.

Examples of aliphatic diamines include ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diamino octane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane and the like.

Alicyclic diamines include, for example, diaminocyclohexane, diaminodicyclohexylmethane, dimethyldiaminodicyclohexylmethane, diaminodicyclohexylpropane, tetramethyldiaminodicyclohexylmethane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl ) cyclohexane, diaminobicyclo[2.2.1]heptane, bis(aminomethyl)-bicyclo[2.2.1]heptane, 3(4),8(9)-bis(aminomethyl)tricyclo[5.2 .1.0(2,6)]decane, isophoronediamine and the like.

Examples of aromatic diamines include
2,2'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diethyl-4,4' -diaminobiphenyls such as diaminobiphenyl, 2,2'-di-n-propyl-4,4'-diaminobiphenyl;
bisaminophenoxyphenylpropanes such as 2,2-bis[4-(3-aminophenoxy)phenyl]propane and 2,2-bis[4-(4-aminophenoxy)phenyl]propane;
diaminodiphenyl ethers such as 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether and 4,4'-diaminodiphenyl ether;
Phenylenediamines such as p-phenylenediamine and m-phenylenediamine;
Diaminodiphenyl sulfides such as 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide;
Diaminodiphenyl sulfones such as 3,3′-diaminodiphenyl sulfone, 3,4′-diaminodiphenyl sulfone, 4,4′-diaminodiphenyl sulfone;
Diaminobenzophenones such as 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 4,4′-diaminobenzophenone;
Diaminodiphenylmethanes such as 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, bis[4-(3-aminophenoxy)phenyl]methane;
Diaminophenylpropanes such as 2,2-di(3-aminophenyl)propane, 2,2-di(4-aminophenyl)propane, 2-(3-aminophenyl)-2-(4-aminophenyl)propane;
2,2-di(3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-di(4-aminophenyl)-1,1,1,3,3, diaminophenyl hexafluoropropanes such as 3-hexafluoropropane, 2-(3-aminophenyl)-2-(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane;
1,1-di(3-aminophenyl)-1-phenylethane, 1,1-di(4-aminophenyl)-1-phenylethane, 1-(3-aminophenyl)-1-(4-aminophenyl )-diaminophenylphenylethane such as 1-phenylethane;
1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy) bisaminophenoxybenzenes such as benzene;
1,3-bis(3-aminobenzoyl)benzene, 1,3-bis(4-aminobenzoyl)benzene, 1,4-bis(3-aminobenzoyl)benzene, 1,4-bis(4-aminobenzoyl) bisaminobenzoylbenzenes such as benzene;
1,3-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,3-bis(4-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(3-amino-α, bisaminodimethylbenzylbenzenes such as α-dimethylbenzyl)benzene, 1,4-bis(4-amino-α,α-dimethylbenzyl)benzene;
1,3-bis(3-amino-α,α-ditrifluoromethylbenzyl)benzene, 1,3-bis(4-amino-α,α-ditrifluoromethylbenzyl)benzene, 1,4-bis(3- bisaminoditrifluoromethylbenzylbenzenes such as amino-α,α-ditrifluoromethylbenzyl)benzene, 1,4-bis(4-amino-α,α-ditrifluoromethylbenzyl)benzene;
aminophenoxybiphenyls such as 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, bis[1-(3-aminophenoxy)]biphenyl;
aminophenoxyphenyl ketones such as bis[4-(3-aminophenoxy)phenyl]ketone and bis[4-(4-aminophenoxy)phenyl]ketone;
aminophenoxyphenyl sulfides such as bis[4-(3-aminophenoxy)phenyl]sulfide and bis[4-(4-aminophenoxy)phenyl]sulfide;
aminophenoxyphenyl sulfones such as bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(4-aminophenoxy)phenyl]sulfone;
aminophenoxyphenyl ethers such as bis[4-(3-aminophenoxy)phenyl]ether and bis[4-(4-aminophenoxy)phenyl]ether;
2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane , 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane;
1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-aminophenoxy) bis(aminophenoxybenzoyl)benzenes such as benzoyl]benzene, 1,4-bis[4-(4-aminophenoxy)benzoyl]benzene;
1,3-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1, 4-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, bis(amino phenoxy-α,α-dimethylbenzyl)benzene;
bis[(aminoaryloxy)benzoyl]diphenyl ether such as 4,4′-bis[4-(4-aminophenoxy)benzoyl]diphenyl ether;
Bis(amino-α,α-dimethylbenzylphenoxy)benzophenones such as 4,4′-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]benzophenone:
bis[amino-α,α-dimethylbenzylphenoxy]diphenylsulfone such as 4,4′-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenylsulfone;
bis[aminophenoxyphenoxy]diphenylsulfone such as 4,4′-bis[4-(4-aminophenoxy)phenoxy]diphenylsulfone;
diaminodiaryloxybenzophenones such as 3,3′-diamino-4,4′-diphenoxybenzophenone and 3,3′-diamino-4,4′-dibiphenoxybenzophenone;
Diaminoaryloxybenzophenones such as 3,3′-diamino-4-phenoxybenzophenone and 3,3′-diamino-4-biphenoxybenzophenone;
1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-indene-5-amine and the like.

Diamino ethers include, for example, bis(aminomethyl)ether, bis(2-aminoethyl)ether, bis(3-aminopropyl)ether, bis(2-aminomethoxy)ethyl]ether, bis[2-( 2-aminoethoxy)ethyl]ether, bis[2-(3-aminoprotoxy)ethyl]ether, 1,2-bis(aminomethoxy)ethane, 1,2-bis(2-aminoethoxy)ethane, 1, 2-bis[2-(aminomethoxy)ethoxy]ethane, 1,2-bis[2-(2-aminoethoxy)ethoxy]ethane, ethylene glycol bis(3-aminopropyl) ether, diethylene glycol bis(3- aminopropyl) ether, triethylene glycol bis(3-aminopropyl) ether and the like.

Examples of diaminopolysiloxane include α,ω-bis(2-aminoethyl)polydimethylsiloxane, α,ω-bis(3-aminopropyl)polydimethylsiloxane, α,ω-bis(4-aminobutyl)poly Dimethylsiloxane, α,ω-bis(5-aminopentyl)polydimethylsiloxane, α,ω-bis[3-(2-aminophenyl)propyl]polydimethylsiloxane, α,ω-bis[3-(4-amino phenyl)propyl]polydimethylsiloxane and the like.

These (a2-1) components may be used alone or in combination of two or more. Among them, alicyclic diamines and aromatic diamines are preferred, and aromatic diamines are more preferred, since the adhesive layer exhibits excellent solder heat resistance.

The amount of component (a2-1) used in 100 mol % of the monomer group constituting component (A) is not particularly limited, and is usually 90 mol % or less, preferably 50 mol % or less.

The amount of component (a2-1) used in 100 mol % of component (a2) is not particularly limited, and is usually 90 mol % or less, preferably 70 mol % or less.

The (A) component of the present invention can be obtained by various known production methods. As the production method thereof, for example, a monomer group containing components (a1) and (a2) is heated at a temperature of preferably about 30 to 120° C., more preferably about 40 to 100° C., for a time of preferably 0.1 to 100° C. A step of conducting a polyaddition reaction for about 2 hours, more preferably about 0.1 to 0.5 hours to obtain a polyadduct. A method including a step of imidization reaction, ie dehydration ring closure reaction, at a temperature of about 170° C. for preferably about 0.5 to 50 hours, more preferably about 1 to 20 hours. The method and order of mixing the components (a1) and (a2) are not particularly limited.

In addition, in the imidization reaction step, various known reaction catalysts, dehydrating agents, and organic solvents may be used, and these may 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. The dehydrating agent includes aliphatic carboxylic acid anhydrides such as acetic anhydride and aromatic carboxylic acid anhydrides such as benzoic anhydride.

Examples of organic solvents include N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, diazabicycloundecene, and the like. Nitrogen-based organic solvents; ketones such as methyl ethyl ketone, diethyl ketone, cyclopentanone, cyclohexanone, and methylcyclohexanone; ethers such as 1,2-dimethoxyethane, 1,2-diethoxyethane, tetrahydrofuran, and dioxane; methanol, ethanol, n- alcohols such as propyl alcohol, isopropyl alcohol, 1-methoxy-2-propyl alcohol and t-butyl alcohol; aliphatic hydrocarbons such as hexane and heptane; alicyclic hydrocarbons such as cyclohexane, methylcyclohexane and ethylcyclohexane; aromatic hydrocarbons such as toluene and xylene; ethyl acetate, dimethylsulfoxide and the like; These may be used alone or in combination of two or more. When an organic solvent is used, the amount used is adjusted so that the reaction concentration is 5 to 60% by weight, preferably 20 to 50% by weight.

Although the imide ring closure rate of component (A) is not particularly limited, it is preferably 90 to 100%, more preferably about 95 to 100%, in terms of obtaining component (A) having both high softening point and flexibility. Here, the "imido ring closure rate" means the content of cyclic imide bonds in the polyimide of the component (A), and can be determined by various spectroscopic means such as NMR and IR analysis.

The physical properties of component (A) are not particularly limited. The weight average molecular weight of component (A) is preferably 20,000 to 100,000. Component (A) preferably has a number average molecular weight of 5,000 to 50,000. A weight average molecular weight and a number average molecular weight are calculated|required as a polystyrene conversion value measured by a gel permeation chromatography (GPC), for example.

The softening point of component (A) of the present invention is preferably about 50 to 250°C, more preferably about 80 to 200°C. The softening point is the temperature at which the storage modulus begins to decrease in the storage modulus profile measured using a commercially available measuring instrument (product name “ARES-2KSTD-FCO-STD”, manufactured by Rheometric Scientific). Point.

Component (B) is a liquid crystal polymer filler. By containing the component (B), the adhesive layer exhibits excellent solder heat resistance and also has low dielectric properties.

"Liquid crystal polymer" is a melt processability that has the property of forming an optically anisotropic melt phase (when the molten liquid crystal polymer is sheared, the molecular chains are oriented in that direction and anisotropy occurs). and has a rigid molecular skeleton, so it is excellent in mechanical strength and heat resistance.
Further, "liquid crystal polymer filler" means a filler (filler) made of a liquid crystal polymer, and its shape includes powder, spherical (including nearly spherical), spindle-shaped, amorphous particulate, fibrous, etc., and mixtures thereof.

The type of component (B) is not particularly limited, and examples thereof include aromatic polyesters and/or aromatic polyesteramides. The component (B) also includes polyesters partially containing aromatic polyesters and/or aromatic polyesteramides in the same molecular chain.

Aromatic hydroxycarboxylic acids, aromatic diols, aromatic dicarboxylic acids and the like are mainly used as constituent monomers of component (B).

Examples of aromatic hydroxycarboxylic acids include hydroxybenzoic acids such as p-hydroxybenzoic acid, m-hydroxybenzoic acid and o-hydroxybenzoic acid; 3-hydroxy-2-naphthoic acid and 5-hydroxy-2-naphthoic acid. , hydroxynaphthoic acids such as 6-hydroxy-2-naphthoic acid; phenylbenzoic acids; 4-hydroxy-4'-biphenylcarboxylic acid and the like. Acid anhydrides, acylates, esters and acid halides of these carboxylic acids may also be used. These may be used alone or in combination of two or more.

Examples of aromatic diols include resorcinol, hydroquinone, methylhydroquinone, 4,4'-isopropylidenediphenol, 1,4-dihydroxynaphthalene, 3,3'-dihydroxybiphenyl, 3,4'-dihydroxybiphenyl, 4, 4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl ether, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene and the like. Also, acylated products, esters and acid halides thereof may be used. These may be used alone or in combination of two or more.

Examples of aromatic dicarboxylic acids include terephthalic acid, methyl terephthalic acid, isophthalic acid, methylisophthalic acid, 4,4'-biphenyldicarboxylic acid, 2,2'-diphenylpropane-4,4'-dicarboxylic acid, diphenyl ether- 4,4'-dicarboxylic acid, diphenylketone-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid and the like. Acid anhydrides, acylates, esters and acid halides of these carboxylic acids may also be used. These may be used alone or in combination of two or more.

Further, other constituent monomers include o-aminobenzoic acid, m-aminobenzoic acid, p-aminobenzoic acid, 2-amino-6-naphthoic acid, 2-amino-3-naphthoic acid, 1-amino- Aminocarboxylic acids such as 4-naphthoic acid;
Aminophenols such as 2-aminophenol, 3-aminophenol, 4-aminophenol, 4-(N-methylamino)phenol, 3-methyl-4-aminophenol, acetoxyaminophenol;
Aromatic diamines such as 1,3-phenylenediamine, 1,4-phenylenediamine and 4,4'-diaminodiphenyl ether may also be used. These may be used alone or in combination of two or more.

The repeating unit of the constituent monomer in the component (B) and the method for producing the component (B) are not particularly limited, and are disclosed in, for example, JP-A-2011-006629, Japanese Patent No. 6295013, and International Publication No. 2020/166651. things, etc.

As for the physical properties of component (B), for example, the melting point is preferably about 260 to 340°C, more preferably about 290 to 340°C. The melting point here refers to a value measured according to JIS K-7121.
The volume average particle size of component (B) is preferably about 20 μm or less, more preferably about 0.1 to 7 μm. The volume-average particle size herein refers to a volume-based arithmetic average particle size measured by a laser diffraction/scattering particle size distribution measurement method.

Commercially available products of component (B) include, for example, "LF-31P" (manufactured by ENEOS Corporation).

The content of component (B) in the adhesive composition of the present invention is not particularly limited, but since the adhesive layer exhibits a low dielectric loss tangent, in terms of non-volatile content, relative to 100 parts by weight of component (A), About 20 to 300 parts by weight is preferable, about 50 to 250 parts by weight is more preferable, and about 80 to 200 parts by weight is even more preferable.

The adhesive composition of the present invention may contain a cross-linking agent (C) (hereinafter referred to as component (C)). By containing the component (C), the soldering heat resistance of the adhesive layer is likely to be increased.

As component (C), various known components can be used without particular limitation as long as they function as a cross-linking agent for polyimide, and may be used alone or in combination of two or more. Component (C) includes, for example, epoxides, benzoxazines, bismaleimides, cyanate esters, and butadiene-based polymers.

Epoxides include phenol novolac type epoxide, cresol novolac type epoxide, bisphenol A type epoxide, bisphenol F type epoxide, bisphenol S type epoxide, hydrogenated bisphenol A type epoxide, hydrogenated bisphenol F type epoxide, stilbene type epoxide, and triazine skeleton-containing epoxide. , fluorene skeleton-containing epoxide, linear aliphatic epoxide, alicyclic epoxide, glycidylamine-type epoxide, triphenolmethane-type epoxide, alkyl-modified triphenolmethane-type epoxide, biphenyl-type epoxide, dicyclopentadiene skeleton-containing epoxide, naphthalene skeleton-containing Examples include epoxides, arylalkylene type epoxides, tetraglycidylxylylenediamine, dimer acid-modified epoxides which are dimer acid-modified epoxides, dimer acid diglycidyl esters, and the like. In addition, commercially available epoxides include "jER604", "jER630", "jER828", "jER834", and "jER807" manufactured by Mitsubishi Chemical Corporation, and "ST-3000" manufactured by Nippon Steel Chemical & Materials Co., Ltd. ”, “Celoxide 2021P” manufactured by Daicel Corporation, “YD-172-X75” manufactured by Nippon Steel Chemical & Materials Co., Ltd., “TETRAD-X” manufactured by Mitsubishi Gas Chemical Co., Ltd., and the like. Among these, at least one selected from the group consisting of bisphenol A type epoxide, bisphenol F type epoxide, hydrogenated bisphenol A type epoxide and alicyclic epoxide is preferable from the viewpoint of balance between solder heat resistance and low dielectric properties.

In particular, the tetraglycidyldiamine of general formula (3) has good compatibility with the polyimide. In addition, the use of this facilitates the reduction of the loss elastic modulus of the adhesive layer, and also improves the solder heat resistance and low dielectric properties.

（式中、Ｚはフェニレン基又はシクロヘキシレン基を表す。）

(In the formula, Z represents a phenylene group or a cyclohexylene group.)

When an epoxide is used as component (C), various known epoxide curing agents and active ester curing agents can be used in combination. The curing agents may be used alone or in combination of two or more.

Epoxide curing agents include, for example, succinic anhydride, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, 4-methylhexahydro Phthalic anhydride, or a mixture of 4-methylhexahydrophthalic anhydride and hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl-tetrahydrophthalic anhydride, nadic anhydride, methylnadic anhydride, norbornane-2,3-dicarboxylic acid Acid anhydride-based curing agents such as acid anhydride, methylnorbornane-2,3-dicarboxylic anhydride, methylcyclohexenedicarboxylic anhydride, 3-dodecenylsuccinic anhydride, and octenylsuccinic anhydride;
Dicyandiamide (DICY), aromatic diamine (trade name: "Lonzacure M-DEA", "Lonzacure M-DETDA", etc., both manufactured by Lonza Japan Co., Ltd.), amine-based curing agents such as aliphatic amines;
Phenolic curing agents such as phenol novolak resin, cresol novolak resin, bisphenol A type novolak resin, triazine-modified phenol novolac resin, phenolic hydroxyl group-containing phosphazene (manufactured by Otsuka Chemical Co., Ltd., trade name: "SPH-100", etc.);
Rosin-based curing agents such as maleic acid-modified rosin and hydrides thereof;
A cyclic phosphazene-based compound and the like can be mentioned.

Examples of active ester-based curing agents include those containing a dicyclopentadienyldiphenol structure, those containing a naphthalene structure, acetylated phenol novolacs, benzoylated phenol novolacs, and the like described in JP-A-2019-183071. mentioned.
Examples of commercially available active ester curing agents include:
Those containing a dicyclopentadienyl diphenol structure, "EXB9451", "EXB9460", "EXB9460S", "HPC-8000", "HPC-8000H", "HPC-8000-65T", "HPC-8150- 62T", "HPC-8000H-65MT", "HPC-8000L-65MT", "EXB-8000L", "EXB-8000L-65MT", "EXB-8150-65T" (manufactured by DIC Corporation);
containing a naphthalene structure, "EXB9416-70BK" (manufactured by DIC Corporation);
An acetylated product of phenol novolak, "DC808" (manufactured by Mitsubishi Chemical Corporation);
Benzoylated phenol novolaks, such as "YLH1026", "YLH1030", and "YLH1048" (manufactured by Mitsubishi Chemical Corporation).

As the active ester curing agent, those produced by various known methods can also be used, and examples thereof include those obtained by reacting a polyfunctional phenol compound and an aromatic carboxylic acid described in Japanese Patent No. 5,152,445. be done.

Among the curing agents, active ester curing agents, phenolic curing agents, and particularly active ester curing agents are preferred. The amount of the curing agent used is not particularly limited, but is preferably about 0.1 to 40% by weight, more preferably about 1 to 10% by weight, based on 100% by weight of the nonvolatile matter of the adhesive composition.

Moreover, when combining an epoxide and an epoxide curing agent as the component (C), a reaction catalyst can be used in combination. The reaction catalyst may be used alone or in combination of two or more. The reaction catalyst is a tertiary amine such as 1,8-diaza-bicyclo[5.4.0]undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol; imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole and 2-heptadecylimidazole; organic compounds such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine and phenylphosphine; Phosphine; Tetraphenylboron salts such as tetraphenylphosphonium/tetraphenylborate, 2-ethyl-4-methylimidazole/tetraphenylborate, N-methylmorpholine/tetraphenylborate, and the like. The amount of the reaction catalyst used is not particularly limited, but is preferably about 0.01 to 5% by weight based on 100% by weight of the non-volatile matter of the adhesive composition.

Benzoxazines are 6,6-(1-methylethylidene)bis(3,4-dihydro-3-phenyl-2H-1,3-benzoxazine), 6,6-(1-methylethylidene)bis(3, 4-dihydro-3-methyl-2H-1,3-benzoxazine) and the like. A phenyl group, a methyl group, a cyclohexyl group, or the like may be bonded to the nitrogen of the oxazine ring. In addition, commercial products of benzoxazine include "Benzoxazine Fa type" and "Benzoxazine Pd type" manufactured by Shikoku Kasei Co., Ltd., and "RLV-100" manufactured by Air Water. mentioned.

Bismaleimides include 4,4′-diphenylmethanebismaleimide, m-phenylenebismaleimide, bisphenol A diphenylether bismaleimide, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethanebismaleimide, 4- methyl-1,3-phenylenebismaleimide, 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, 4,4'-diphenyletherbismaleimide, 4,4'-diphenylsulfonebismaleimide and the like. be done. Commercially available products of bismaleimide include “BAF-BMI” manufactured by JFE Chemical Co., Ltd., “BMI-1000H” manufactured by Daiwa Kasei Kogyo Co., Ltd., and the like.

Cyanate esters include 2-allylphenol cyanate ester, 4-methoxyphenol cyanate ester, 2,2-bis(4-isocyanatophenyl)-1,1,1,3,3,3-hexafluoropropane, bisphenol A cyanate ester, diallyl bisphenol A cyanate ester, 4-phenylphenol cyanate ester, 1,1,1-tris(4-cyanatophenyl) ethane, 4-cumylphenol cyanate ester, 1,1-bis(4-cyanatophenyl ) ethane, 4,4′-bisphenolcyanate ester, and 2,2-bis(4-cyanatophenyl)propane. Commercially available cyanate esters include "PRIMASET BTP-6020S" manufactured by Lonza Japan Co., Ltd., and the like.

Examples of butadiene-based polymers include polybutadiene, 1,2-butadiene homopolymer, butadiene-isoprene polymer, butadiene-acrylonitrile polymer, ethoxylated polybutadiene, epoxidized polybutadiene, butadiene-styrene polymer, styrene-butadiene-styrene polymer, and the like. In addition, commercially available butadiene-based polymers include “Ricon 100” and “Ricon 184” manufactured by Cray Valley, “NISSO-PB B-1000” and “NISSO-PB JP-200” manufactured by Nippon Soda Co., Ltd. mentioned.

The content of component (C) in the adhesive composition of the present invention is not particularly limited. The content of component (C) is about 1 to 20 parts by weight per 100 parts by weight of component (A) in terms of non-volatile content in order to achieve both excellent soldering heat resistance and low dielectric properties of the adhesive layer. is preferred, about 1.5 to 15 parts by weight is more preferred, and 3 to 10 parts by weight is even more preferred.

The adhesive composition of the present invention may further contain the aforementioned organic solvent. The content thereof is preferably about 30 to 60% by weight with respect to 100% by weight of the adhesive composition.

The adhesive composition of the present invention may contain a flame retardant. A flame retardant may be used alone or in combination of two or more. Examples of flame retardants include phosphorus-based flame retardants and inorganic fillers.

Phosphorus-based flame retardants include polyphosphoric acid, phosphate esters, phosphazene derivatives having no phenolic hydroxyl group, and the like. Among the phosphazene derivatives, cyclic phosphazene derivatives are preferred in terms of flame retardancy, heat resistance, bleed-out resistance and the like. Commercially available cyclic phosphazene derivatives include “SPB-100” manufactured by Otsuka Chemical Co., Ltd., “Ravitoll FP-300B” manufactured by Fushimi Pharmaceutical Co., Ltd., and the like.

Examples of inorganic fillers include silica fillers, phosphorus-based fillers, fluorine-based fillers, inorganic ion exchanger fillers, and the like. As for the silica filler, the surface thereof may be modified with a treating agent such as a silane coupling agent. In addition, commercially available inorganic fillers include “FB-3SDC” and “SFP-20M” manufactured by Denka Co., Ltd., “SC-2500-SPJ” and “SC-2500-SXJ” manufactured by Admatechs Co., Ltd. , “SC-2500-SVJ”, “Exolit OP935” manufactured by Clariant Chemicals Co., Ltd., “KTL-500F” manufactured by Kitamura Co., Ltd., “IXE” manufactured by Toagosei Co., Ltd., and the like.

The content of the flame retardant in the adhesive composition of the present invention is not particularly limited. The content of the flame retardant is preferably 1 to 150 parts by weight in terms of non-volatile content per 100 parts by weight of component (A).

The adhesive composition of the present invention has the general formula: W—Si(R ¹ ) _a (OR ² ) _3-a (wherein W represents a group containing a functional group that reacts with an acid anhydride group, R ¹ represents hydrogen or a hydrocarbon group having 1 to 8 carbon atoms, R ² represents a hydrocarbon group having 1 to 8 carbon atoms, and a represents 0, 1 or 2.) But it's okay. The reactive alkoxysilyl compound allows the melt viscosity of the adhesive layer of the adhesive composition of the present invention to be adjusted while maintaining low dielectric properties. As a result, the bleeding of the hardened layer from the edge of the support can be suppressed while increasing the interfacial adhesive strength (so-called anchor effect) between the adhesive layer and the support.

Examples of the reactive functional group included in W in the general formula include an amino group, an epoxy group and a thiol group.

Compounds in which W contains an amino group include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and 3-aminopropyltrimethoxysilane. , 3-aminopropyltriethoxysilane and 3-ureidopropyltrialkoxysilane. Examples of compounds in which W contains an epoxy group include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, Examples include sidoxypropylmethyldiethoxysilane and 3-glycidoxypropyltriethoxysilane. Examples of compounds in which W contains a thiol group include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropylmethyldiethoxysilane. Among these, a compound in which W contains an amino group is preferable because of good reactivity and flow control effect.

The content of the reactive alkoxysilyl compound in the adhesive composition of the present invention is not particularly limited. The content of the reactive alkoxysilyl compound is preferably 0.01 to 5 parts by weight in terms of non-volatile content per 100 parts by weight of component (A).

The adhesive composition of the present invention may contain additives other than components (A), (B), (C), organic solvents, flame retardants and reactive alkoxysilyl compounds.

Additives include ring-opening esterification reaction catalysts, dehydrating agents, plasticizers, weathering agents, antioxidants, heat stabilizers, lubricants, antistatic agents, brighteners, coloring agents, conductive agents, release agents, and surface treatment. agents, viscosity modifiers, silica fillers and fluorine fillers.

The content of the additive is not particularly limited, but is less than 1 part by weight, less than 0.1 part by weight, less than 0.01 part by weight, 0 part by weight, etc. with respect to 100 parts by weight of the non-volatile matter of the adhesive composition. is mentioned.

The content of the additive is not particularly limited. and the like.

The adhesive composition of the present invention is obtained by mixing components (A) and (B), optionally component (C), an organic solvent, a flame retardant, a reactive alkoxysilyl compound and additives.

[Cured product]
The cured product of the present invention contains the adhesive composition. The method for producing a cured product includes, for example, a step of applying the adhesive composition to a suitable support, a step of curing by heating to volatilize the organic solvent, a step of peeling off the support, and the like. methods and the like. Although the thickness of the cured product is not particularly limited, it is preferably about 3 to 40 μm. Examples of the support include release paper, release film, support film described later, and the like. Moreover, when producing a cured product, the adhesive composition and various known adhesive compositions other than the adhesive may be used in combination.

[Adhesive sheet]
The adhesive sheet of the present invention contains the cured product of the present invention on at least one surface of the support film.

The adhesive sheet can be obtained, for example, by coating the adhesive composition of the present invention on a support film and curing it by heating, or by laminating the cured product of the present invention on a support film.

The support film includes polyimide, polyester, polyimide-silica hybrid, polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, polymethyl methacrylate resin, polystyrene resin, polycarbonate resin, acrylonitrile-butadiene-styrene resin, ethylene terephthalate, phenol, phthalate. Aromatic polyester resin obtained from acid, hydroxynaphthoic acid, etc. and parahydroxybenzoic acid (so-called liquid crystal polymer; Kuraray Co., Ltd., "Vecstar" etc.), cycloolefin polymer, fluorine resin (polytetrafluoroethylene ( PTFE), perfluoroalkoxyalkane (PFA), polyvinylidene fluoride (PVDF), etc.).

When the adhesive composition of the present invention is applied to the support film, the method of application is not particularly limited, and examples thereof include using a coater such as a comma, die, knife, and lip coater. The thickness of the coating layer is also not particularly limited, but the thickness after drying is preferably about 1 to 100 μm, more preferably about 3 to 50 μm. Moreover, the adhesive layer of the adhesive sheet may be protected with various protective films.

[Resin coated copper foil]
The resin-coated copper foil of the present invention includes the cured product of the present invention and copper foil. Specifically, the adhesive composition of the present invention is applied to a copper foil and cured by heating, or the cured product of the present invention is attached to a copper foil. Examples of the copper foil include rolled copper foil and electrolytic copper foil, and those subjected to various surface treatments (roughening, rust prevention, etc.) can also be used. Examples of the anti-rust treatment include plating using a plating solution containing Ni, Zn, Sn, etc., and so-called mirror surface treatment such as chromate treatment.

The thickness of the copper foil is also not particularly limited, preferably about 1 to 100 μm, more preferably about 2 to 38 μm. Moreover, an above-described method is mentioned as a coating means.

Further, the adhesive layer of the resin-coated copper foil may be uncured, or partially cured or completely cured under heating. The partially cured adhesive layer is in a so-called B-stage state. Also, the thickness of the adhesive layer is not particularly limited, and is preferably about 0.5 to 30 μm. Further, resin can be further bonded to the copper foil of the resin-coated copper foil to form a resin-coated copper foil on both sides.

[Copper clad laminate]
The copper-clad laminate of the present invention includes the resin-coated copper foil, copper foil, or insulating sheet of the present invention. A copper clad laminate is also called CCL (Copper Clad Laminate). Specifically, the copper-clad laminate is obtained by press-bonding the resin-coated copper foil to at least one side or both sides of various known copper foils or insulating sheets under heating. In the case of lamination on one side, a material different from the resin-coated copper foil may be pressure-bonded to the other side. Further, the number of resin-coated copper foils, copper foils and insulating sheets in the copper-clad laminate is not particularly limited.

In one embodiment, the insulating sheet is preferably a prepreg or the support film described above. A prepreg is a sheet-like material obtained by impregnating a reinforcing material such as a glass cloth with a resin and curing it to the B stage (JIS C 5603). Insulating resins such as the component (A) of the present invention, phenolic resins, epoxy resins, polyester resins, liquid crystal polymers and aramid resins are used as the resin. The thickness of the insulating sheet is not particularly limited, and is preferably about 20 to 500 μm. The heating/pressing conditions are not particularly limited, and are preferably about 150 to 280° C. (more preferably about 170 to 240° C.) and preferably about 0.5 to 20 MPa (more preferably about 1 to 8 MPa).

[Printed wiring board]
The printed wiring board of the present invention has a circuit pattern on the copper foil surface of the copper-clad laminate of the present invention. Patterning means for forming a circuit pattern on the copper foil surface of a copper-clad laminate include a subtractive method and a semi-additive method. The semi-additive method includes a method of patterning the copper foil surface of the copper-clad laminate with a resist film, performing electrolytic copper plating, removing the resist, and etching with an alkaline solution. Moreover, the thickness of the circuit pattern layer in the printed wiring board is not particularly limited. A multilayer board can also be obtained by using the printed wiring board as a core and laminating the same printed wiring board or other known printed wiring board or printed circuit board thereon. At the time of lamination, the above-mentioned adhesive composition and other known adhesive compositions other than the above-mentioned adhesive composition can be used together. Also, the number of laminations in the multilayer substrate is not particularly limited. Also, each time lamination is performed, a via hole may be inserted and the inside thereof may be plated. Although the line/space ratio of the circuit pattern is not particularly limited, it is preferably about 1 μm/1 μm to 100 μm/100 μm. Also, the height of the circuit pattern is not particularly limited, but is preferably about 1 to 50 μm.

The present invention will be specifically described below with reference to examples, but the present invention is not particularly limited to these. In addition, all "%" are based on weight unless otherwise specified.

Production example 1
4,4'-[Propane-2,2-diylbis(1,4-phenyleneoxy)]diphthalic dianhydride (product Name: "BisDA-1000", manufactured by SABIC Innovative Plastics Japan LLC. Hereinafter abbreviated as BisDA.), 371.38 g of 1,2-dimethoxyethane and 866.56 g of toluene were charged and heated to 70°C. heated. Next, after gradually adding 276.92 g of dimer diamine (trade name: "PRIAMINE 1075", manufactured by Croda Japan Co., Ltd., hereinafter referred to as PRIAMINE 1075), the mixture was heated to 110°C and imidization reaction was carried out over 12 hours. Thus, a solution of polyimide (A-1) (30% non-volatile content) was obtained.

Production example 2
280.00 g of BisDA-1000, 346.99 g of 1,2-dimethoxyethane and 809.65 g of toluene were placed in the same reactor as in Production Example 1 and heated to 70°C. Then, 20.54 g of 4,4'-diaminophenyl ether (trade name: "ODA", manufactured by Wakayama Seika Kogyo Co., Ltd., hereinafter abbreviated as ODA) and 242.08 g of dimer diamine (PRIAMINE 1075) were gradually added. After that, the mixture was heated to 110° C. and an imidization reaction was carried out over 12 hours to obtain a solution of polyimide (A-2) (30% non-volatile content).

Production example 3
Into the same reaction vessel as in Production Example 1, 260 g of 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (manufactured by Daikin Co., Ltd., hereinafter abbreviated as 6FDA), 1,2 - 372.63 g of dimethoxyethane and 869.47 g of toluene were charged and heated to 70°C. Then, after gradually adding 301.00 g of dimer diamine (PRIAMINE 1075), the solution of polyimide (A-3) (30% non-volatile content) was obtained by heating to 110° C. and carrying out an imidation reaction over 14 hours. got

Example 1
As polyimide, (A-1) 100.0 g (non-volatile content 30.0 g) and (A-2) 233.3 g (non-volatile content 70.0 g) (weight ratio in non-volatile content: (A-1) / (A -2) = 30/70), liquid crystal polymer filler (trade name: “LF-31P”, volume average particle diameter: 5 μm, melting point: 320 ° C., manufactured by ENEOS Corporation) 108.7 g (nonvolatile content 108.7 g) , As a cross-linking agent, polyfunctional epoxy resin (trade name: "TETRAD-X", manufactured by Mitsubishi Gas Chemical Co., Ltd.) 2.7 g (non-volatile content 2.7 g) and active ester resin (trade name: "EPICLON HPC-8000 -65T", manufactured by DIC Corporation) 9.2 g (non-volatile content 6.0 g), as a reaction catalyst, an imidazole-based epoxy resin (trade name: "Curesol 2E4MZ-A", manufactured by Shikoku Kasei Kogyo Co., Ltd.) 0. 029 g (0.029 g of non-volatile content), 53.3 g of 1,2-dimethoxyethane as an organic solvent and 217.4 g of methyl ethyl ketone were mixed and thoroughly stirred to obtain an adhesive composition having a non-volatile content of 30%.

Examples 2-8, Comparative Examples 1-2
Using the compositions shown in Table 1, adhesive compositions were obtained in the same manner as in Example 1.

<Preparation of adhesive layer>
Each adhesive composition was applied to a release paper (manufactured by San A Kaken Co., Ltd.) with a gap coater so that the thickness after drying was 25 μm, and then dried at 150 ° C. for 5 minutes to form an adhesive sheet (release paper /adhesive layer) was obtained. Next, the release paper is peeled off from the adhesive sheet (release paper/adhesive layer), the adhesive layer is placed on a press support, and the adhesive layer is pressed through the same press support. By curing with a hot press at 5 MPa and 180° C. for 90 minutes, an adhesive sheet (support/adhesive layer/support) after thermal curing was produced. The support for pressing was removed from the adhesive sheet to obtain an adhesive layer.

<Measurement of dielectric constant and dielectric loss tangent>
Using a network analyzer (manufactured by Keysight Technologies, device name: "P5003A") and a split post dielectric resonator (manufactured by QWED) with a measurement frequency of 10.124 GHz, the resonance frequency of a single resonator with nothing inserted and The Q value of the peak was measured.
Next, after cutting the adhesive layer to a size of 4 cm x 5 cm to prepare a test piece, a plurality of test pieces are superimposed so that the total thickness is 100 μm or more, and inserted into the resonator. The resonance frequency and Q value were measured when the piece was inserted.
The dielectric constant (Dk) is calculated from the difference in resonance frequency between the resonator alone and the test piece inserted. It was calculated from the difference in resonance frequency. Table 1 shows the results.

＊１：各成分の重量部については、不揮発分での重量を表す。

*1: Parts by weight of each component represent the weight of non-volatile matter.

The symbols shown in Table 1 represent the following compounds.
<Polyimide>
・A-1-Polyimide of Production Example 1 ・A-2-Polyimide of Production Example 2 ・A-3-Polyimide of Production Example 3 <Filler>
・B-1-liquid crystal polymer filler, trade name: “LF-31P”, volume average particle size: 5 μm, melting point: 320° C., manufactured by ENEOS ・D-1-unmodified silica, trade name: “SC2500- SPJ”, volume average particle size: 0.5 μm, manufactured by Admatechs Co., Ltd. <crosslinking agent>
· C-1-polyfunctional epoxy resin, trade name: "TETRAD-X", manufactured by Mitsubishi Gas Chemical Co., Ltd. · C-2-active ester resin, trade name: "EPICLON HPC-8000-65T", DIC Corporation ), C-3-active ester resin, trade name: "EPICLON HPC-8150-62T", manufactured by DIC Corporation

The following tests evaluated adhesive compositions containing a crosslinker.

Evaluation Examples 1 to 7, Comparative Evaluation Examples 1 and 2
<Preparation of adhesive sheet>
The adhesive compositions of Examples 1 to 7 and Comparative Examples 1 and 2 were applied to release paper (manufactured by San A Kaken Co., Ltd.) with a gap coater so that the thickness after drying was 25 μm, and then heated at 150 ° C. and dried for 5 minutes to obtain an adhesive sheet (release paper/adhesive layer).

<Preparation of copper-clad laminate>
Peel off the release paper from the adhesive sheet (release paper/adhesive layer), and put it on the mirror surface side of commercially available electrolytic copper foil (product name “F2-WS”, manufactured by Furukawa Electric Co., Ltd.) (thickness 18 μm). , The other surface is overlaid on a commercially available polyimide film (trade name: “Kapton 100EN”, manufactured by Toray Dupont Co., Ltd.; film thickness 25 μm; thermal expansion coefficient; 15 ppm / ° C.), and a laminate (polyimide film / adhesive sheet/copper foil).
Next, the laminate is placed on a support for pressing so that the copper foil surface is in contact, and is cured by a heat press at a pressure of 10 MPa and a temperature of 180° C. for 90 minutes through a support made of the same material from above. A copper-clad laminate (polyimide film/adhesive layer/electrolytic copper foil) was produced.

<Adhesion test>
The peel strength (N/mm) of the copper-clad laminate was measured according to JIS C 6481 (testing method for copper-clad laminate for flexible printed wiring boards). Table 2 shows the results.

<Solder heat resistance test>
After leaving the copper-clad laminate in a temperature-controlled room at a temperature of 23° C. and a humidity of 50% for 24 hours, it is floated in a solder bath at 288° C. with the copper foil side down, and the presence or absence of foaming is confirmed. evaluated with Table 2 shows the results.
(Evaluation criteria)
○: No change in appearance ×: Foaming and blistering

Example 9, Comparative Example 3
After each adhesive composition was obtained with the composition shown in Table 3, the dielectric constant and dielectric loss tangent were measured in the same manner as described above. Table 3 shows the results.

＊２：各成分の重量部については、不揮発分での重量を表す。

*2: Parts by weight of each component represent the weight of non-volatile matter.

The symbols shown in Table 3 represent the following compounds.
<Polyimide>
・ A-3-polyimide <filler> of Production Example 3
・B-1-liquid crystal polymer filler, trade name: “LF-31P”, volume average particle size: 5 μm, melting point: 320° C., manufactured by ENEOS ・D-1-unmodified silica, trade name: “SC2500- SPJ”, volume average particle size: 0.5 μm, manufactured by Admatechs Co., Ltd. <crosslinking agent>
· C-1-polyfunctional epoxy resin, trade name: "TETRAD-X", manufactured by Mitsubishi Gas Chemical Co., Ltd. · C-2-active ester resin, trade name: "EPICLON HPC-8000-65T", DIC Corporation ) made

Evaluation Example 8, Comparative Evaluation Example 3
The adhesive compositions of Example 9 and Comparative Example 3 were coated on release paper (manufactured by San A Kaken Co., Ltd.) with a gap coater so that the thickness after drying was 25 μm, and then dried at 150 ° C. for 5 minutes. to obtain an adhesive sheet (release paper/adhesive layer).
A double-sided copper-clad laminate (trade name: “Pyralux TK125012R” manufactured by Dupont; film thickness 75 μm) in which copper foil/fluororesin is laminated on both sides of a polyimide film is etched with a 40% iron (III) chloride aqueous solution to obtain copper. Removed the foil. Next, each adhesive sheet is overlaid on one side of the exposed fluororesin, and a commercially available electrolytic copper foil (trade name: "F2-WS", manufactured by Furukawa Circuit Foil Co., Ltd., 18 μm thick) is overlaid and laminated. A body (fluororesin layer/polyimide film/fluororesin layer/adhesive layer/electrolytic copper foil) was produced.
Next, the laminate is placed on a support for pressing so that the copper foil surface is in contact, and is cured by a heat press at a pressure of 10 MPa and a temperature of 180° C. for 90 minutes through a support made of the same material from above. A copper-clad laminate was produced by allowing the The obtained copper-clad laminate was measured for peel strength (N/mm) in the same manner as described above. Table 4 shows the results.

Examples 10, 11, Comparative Example 4
After obtaining each adhesive composition with the composition shown in Table 5, the dielectric constant and dielectric loss tangent were measured in the same manner as described above. Table 5 shows the results.

＊３：各成分の重量部については、不揮発分での重量を表す。

*3: Parts by weight of each component represent the weight of non-volatile matter.

The symbols shown in Table 5 represent the following compounds.
<Polyimide>
・ A-1-polyimide <filler> of Production Example 1
・B-1-liquid crystal polymer filler, trade name: “LF-31P”, volume average particle size: 5 μm, melting point: 320° C., manufactured by ENEOS ・D-1-unmodified silica, trade name: “SC2500- SPJ”, volume average particle size: 0.5 μm, manufactured by Admatechs Co., Ltd. <crosslinking agent>
・C-4-polyfunctional epoxy resin, trade name: “jER604”, manufactured by Mitsubishi Chemical Corporation ・C-5-active ester resin, trade name: “EPICLON HPC-8000-65MT”, manufactured by DIC Corporation ・C-6-4,4'-diphenylmethane bismaleimide, trade name: "BMI-1000H", C-7-butadiene-styrene polymer manufactured by Daiwa Kasei Kogyo Co., Ltd., trade name: "Ricon-100", Cray Valley manufactured by the company

Evaluation Examples 9 and 10, Comparative Evaluation Example 4
The adhesive compositions of Examples 10 and 11 and Comparative Example 4 were coated on release paper (manufactured by San A Kaken Co., Ltd.) with a gap coater so that the thickness after drying was 25 μm, and then coated at 150° C. for 5 hours. After drying for a minute, an adhesive sheet (release paper/adhesive layer) was obtained.
Each adhesive sheet is placed on the liquid crystal polymer side of a single-sided copper-clad laminate (trade name: “LDS-1250”, manufactured by Azotech; film thickness: 50 μm) in which an electrolytic copper foil is laminated on one side of the liquid crystal polymer, and further A laminate (electrolytic copper foil/liquid crystal polymer/adhesive layer/electrolytic copper foil/liquid crystal polymer) was prepared by stacking similar single-sided copper clad laminates (LDS-1250) from the copper foil side.
Next, the laminate is placed on a support for pressing, and cured by a heat press at a pressure of 2.5 MPa and a temperature of 180° C. for 90 minutes through a support made of the same material from above to obtain a copper clad. A laminate was produced. The obtained copper-clad laminate was measured for peel strength (N/mm) and solder heat resistance in the same manner as described above. Table 6 shows the results.

Claims (10)

An adhesive composition comprising a polyimide (A) which is a reactant of a monomer group containing an aromatic tetracarboxylic anhydride (a1) and a diamine (a2) containing a dimer diamine, and a liquid crystal polymer filler (B). 2. The adhesive composition according to claim 1, wherein the component (a2) further contains an alicyclic diamine and/or an aromatic diamine. 3. The adhesive composition according to claim 1, wherein the content of component (B) is 20 to 300 parts by weight in terms of non-volatile content per 100 parts by weight of component (A). The adhesive composition according to any one of claims 1 to 3, further comprising a cross-linking agent (C). The adhesive composition according to any one of claims 1 to 4, wherein the content of component (C) is 1 to 20 parts by weight in terms of non-volatile content per 100 parts by weight of component (A). A cured product of the adhesive composition according to any one of claims 1 to 5. An adhesive sheet having the cured product according to claim 6 on at least one side of a support film. A resin-coated copper foil comprising the cured product according to claim 6 and a copper foil. A copper-clad laminate comprising the resin-coated copper foil according to claim 8 and a copper foil or an insulating sheet. A printed wiring board having a circuit pattern on the copper foil surface of the copper-clad laminate according to claim 9 .