TW202242060A - Adhesive composition, and bonding sheet, multilayer body and printed wiring board each containing same - Google Patents

Abstract

To provide: an adhesive composition which has excellent heat resistance, excellent adhesive strength, low relative dielectric constant, low dielectric loss tangent and excellent dielectric characteristics; and a bonding sheet, a multilayer body and a printed wiring board, each of which comprises this adhesive composition. An adhesive composition which contains an acid-modified resin, a compound A and a compound B. Compound A: a compound which has a terminal unsaturated hydrocarbon group, while having a 5% weight loss temperature of 260 DEG C or more Compound B: a compound which has an epoxy group and a terminal unsaturated hydrocarbon group.

Description

Adhesive composition, and adhesive sheet, laminate and printed wiring board containing the adhesive

The present invention relates to adhesive compositions. More specifically, it relates to an adhesive composition used for bonding a resin substrate and a resin substrate or a metal substrate. In particular, it relates to an adhesive composition for a flexible printed wiring board (hereinafter referred to as FPC), an adhesive sheet, a laminate, and a printed wiring board containing the adhesive.

Due to its excellent flexibility, FPC can correspond to the multi-function and miniaturization of personal computers (PCs) and smartphones, and is often used to incorporate electronic circuit boards into narrow and complicated interiors. In recent years, the miniaturization, light weight, high density, and high output of electronic equipment have progressed, and the requirements for the performance of wiring boards (electronic circuit substrates) have been increasing. In particular, in order to increase the transmission speed in FPC, high-frequency signals are used. With the use of such high-frequency signals, the low dielectric characteristics (low dielectric constant, low dielectric loss tangent) required for FPC in the high-frequency region are also increased. In order to achieve such low dielectric properties, some people have proposed a method to reduce the dielectric loss of FPC substrates or adhesives, etc., and for the substrates used in FPC, not only the known polyimide (PI), polyamide Ethylene terephthalate (PET), and substrate films such as liquid crystal polymer (LCP) with low dielectric properties and parallel polystyrene (SPS) have been proposed. As for the adhesive, development of a combination of polyolefin and epoxy (Patent Document 1) or the like, or development of an adhesive using polyphenylene ether (Patent Document 2) or the like is in progress. [Prior Art Literature] [Patent Document]

[Patent Document 1] WO2016/047289 Publication [Patent Document 2] WO2020/196718 Publication

[Problem to be Solved by the Invention]

However, since the adhesive described in Patent Document 1 contains epoxy resin and epoxy resin hardener, it has high polarity and cannot meet the requirement for a high dielectric loss tangent. In addition, the adhesive described in Patent Document 2 hardly has excellent heat resistance as an FPC adhesive, and is also insufficient in terms of dielectric properties.

The present invention is made on the background of this prior art subject. That is, the object of the present invention is to provide an adhesive composition with excellent heat resistance and adhesive strength, low relative permittivity and dielectric loss tangent, and excellent dielectric properties, and an adhesive sheet containing the adhesive , Laminates and printed wiring boards. [Means to solve the problem]

As a result of intensive research, the present inventors have found that the above-mentioned problems can be solved by the following means, and the present invention has been completed. That is, the present invention is composed of the following structures.

[1] An adhesive composition containing an acid-modified resin, compound A and compound B; Compound A: a compound with a terminal unsaturated hydrocarbon group and a 5% weight loss temperature of 260°C or higher; Compound B: a compound having an epoxy group and a terminal unsaturated hydrocarbon group. [2] The adhesive composition according to [1] above, wherein the acid-modified resin contains at least one selected from acid-modified polyolefin, acid-modified polystyrene resin, and acid-modified cycloolefin polymer resin. [3] The adhesive composition according to the aforementioned [1] or [2], wherein the aforementioned compound A is a compound having an aromatic ring structure or an alicyclic structure as a structural unit. [4] The adhesive composition according to the aforementioned [1] or [2], wherein the aforementioned compound A is a polyphenylene ether or a phenolic resin having a terminal unsaturated hydrocarbon group. [5] The adhesive composition according to the aforementioned [1] to [4], wherein the aforementioned compound B is a compound having an isocyanuric acid ring. [6] An adhesive sheet having an adhesive layer composed of the adhesive composition as described in [1] to [5] above. [7] A laminate having an adhesive layer composed of the adhesive composition as described in [1] to [5] above. [8] A printed wiring board comprising the laminate according to the aforementioned [7] as a constituent element. [Effect of Invention]

The adhesive composition of the present invention has excellent dielectric properties, adhesive strength, and solder heat resistance. Therefore, it is suitable for adhesives for printed wiring boards, adhesive sheets, laminates, and printed wiring boards in high-frequency regions.

Hereinafter, one form of implementation of the present invention will be described in detail as follows. However, the present invention is not limited thereto, and can be implemented in variously modified forms within the range described above.

＜Acid modified resin＞ The acid-modified resin used in the present invention is a resin modified using an acid component. By using an acid-modified resin, it has excellent adhesion to metal substrates such as copper foil, and can form an adhesive layer with excellent solder heat resistance by cross-linking reaction with the epoxy group of compound B described later.

The acid-modified resin used in the present invention can be obtained, for example, by modifying a base resin with an unsaturated carboxylic acid component, or by copolymerizing an unsaturated carboxylic acid component during polymerization of a base resin. The unsaturated carboxylic acid component is not particularly limited, and examples thereof include acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid, maleic anhydride, itaconic anhydride, and fumaric anhydride.

The lower limit of the acid value of the acid-modified resin used in the present invention is preferably 10 equivalents/10 ⁶ g or more, and 20 equivalents/10 ⁶ g or more in consideration of heat resistance and adhesion to resin substrates and metal substrates. More preferably, it is more preferably 30 equivalents/10 ⁶ g or more. When it is more than the said value, compatibility with compound B etc. improves, adhesive strength improves, and heat resistance can also be improved by raising a crosslinking density. The upper limit is preferably not more than 1000 equivalents/10 ⁶ g, more preferably not more than 700 equivalents/10 ⁶ g, and still more preferably not more than 500 equivalents/10 ⁶ g. When it is below the said value, adhesiveness and a low dielectric characteristic will become more favorable.

The number average molecular weight (Mn) of the acid-modified resin used in the present invention is preferably in the range of 10,000-50,000. The range of 15,000~45,000 is more preferable, the range of 20,000~40,000 is even better, and the range of 22,000~38,000 is especially preferable. By setting it as more than the said lower limit value, cohesive force can be made favorable and excellent adhesiveness can be expressed. Moreover, by setting it as below the said upper limit, fluidity|liquidity becomes excellent and handleability becomes favorable.

As far as the acid-modified resin used in the present invention is concerned, it is preferably an acid-modified resin obtained by acid-modifying a resin mainly based on hydrocarbons, for example, an acid-modified polyphenylene resin is preferably acid-modified from the viewpoint of good low dielectric properties. Vinyl resin, acid-modified cyclic olefin polymer, acid-modified polyolefin. In addition, acid-modified polystyrene resins and acid-modified cycloolefin polymers are preferable from the viewpoint of pot life characteristics. The acid-modified resins can be used alone or in combination of two or more.

The acid-modified resin of the present invention preferably has a relative dielectric constant (εc) of 2.7 or less at a frequency of 10 GHz. It is more preferably below 2.6, and even more preferably below 2.3. The lower limit is not particularly limited, and is practically 2.0. Also, the relative permittivity (εc) in the entire frequency range of 1 GHz to 60 GHz is preferably 2.7 or less, more preferably 2.6 or less, and even more preferably 2.3 or less.

The dielectric loss tangent (tanδ) of the acid-modified resin of the present invention at a frequency of 10 GHz is preferably 0.003 or less. It is more preferably not more than 0.0025, and more preferably not more than 0.002. The lower limit is not particularly limited, but is practically 0.0001 or more. Also, the dielectric loss tangent (tan δ) in the entire frequency range of 1 GHz to 60 GHz is preferably not more than 0.003, more preferably not more than 0.0025, and even more preferably not more than 0.002.

The content of the acid-modified resin in the adhesive composition of the present invention is preferably at least 10% by mass, more preferably at least 20% by mass, and even more preferably at least 40% by mass. Moreover, it is preferably at most 99% by mass, more preferably at most 95% by mass, and even more preferably at most 90% by mass. If it is in the said range, since adhesiveness and heat resistance will become favorable, it is preferable.

＜Acid-modified polyolefin＞ In the present invention, an acid-modified polyolefin can be desirably used as the acid-modified resin. The acid-modified polyolefin used in the present invention is not limited, and is preferably obtained by grafting at least one of α,β-unsaturated carboxylic acid and its anhydride on polyolefin resin. Polyolefin resin refers to homopolymers of olefin monomers exemplified by ethylene, propylene, butene, butadiene, isoprene, etc., or copolymers with other monomers, and hydrogenated products of the obtained polymers, Halides and other polymers with a hydrocarbon skeleton as the main body. The acid-modified polyolefin is preferably obtained by grafting at least one of α,β-unsaturated carboxylic acid and its anhydride to polyethylene, polypropylene and propylene-α-olefin copolymer.

Propylene-α-olefin copolymers are made by copolymerizing α-olefins with propylene as the main body. One or more kinds of α-olefins can be used, for example, ethylene, 1-butene, 1-heptene, 1-octene, 4-methyl-1-pentene, vinyl acetate and the like. Among these α-olefins, ethylene and 1-butene are preferable. The ratio of the propylene component to the α-olefin component in the propylene-α-olefin copolymer is not limited, but the propylene component is preferably at least 50 mol%, more preferably at least 70 mol%.

Examples of at least one of α,β-unsaturated carboxylic acids and their anhydrides include maleic acid, itaconic acid, citraconic acid, and their anhydrides. Among them, acid anhydride is preferable, and maleic anhydride is more preferable. That is, acid-modified polyolefins specifically include maleic anhydride-modified polypropylene, maleic anhydride-modified propylene-ethylene copolymer, maleic anhydride-modified propylene-butene copolymer, maleic anhydride-modified propylene- An ethylene-butene copolymer, etc. These acid-modified polyolefins may be used alone or in combination of two or more.

The lower limit of the acid value of the acid-modified polyolefin is preferably 89 equivalents/10 ⁶ g or more, more preferably 107 equivalents/10 ⁶ g or more, in consideration of heat resistance and adhesion to resin substrates and metal substrates. It is more preferably 125 equivalents/10 ⁶ g or more. By setting it as more than the said lower limit, compatibility with compound B can be made favorable and excellent adhesive strength can be exhibited. In addition, the crosslink density is improved and the heat resistance of the solder is improved. The upper limit is preferably not more than 713 equivalents/10 ⁶ g, more preferably not more than 534 equivalents/10 ⁶ g, and still more preferably not more than 356 equivalents/10 ⁶ g. Adhesiveness becomes favorable by setting it as below the said upper limit. In addition, the viscosity and stability of the solution can be improved, and excellent pot life characteristics can be exhibited. In addition, manufacturing efficiency is also improved.

The acid-modified polyolefin is preferably a crystalline acid-modified polyolefin. The term "crystallinity" in the present invention means that the temperature is raised from -100°C to 250°C at 20°C/min using a differential scanning calorimeter (DSC), and a clear melting peak is exhibited during the heating process.

The melting point (Tm) of the acid-modified polyolefin is preferably in the range of 50°C to 120°C. The range of 60°C~100°C is better, and the range of 70°C~90°C is the best. By setting it as more than the said lower limit value, the cohesive force originating in a crystal|crystallization can be made favorable, and excellent adhesiveness and solder heat resistance can be exhibited. Moreover, by setting it as below the said upper limit, the stability and fluidity of a solution are excellent, and the workability|operativity at the time of adhering becomes favorable.

The heat of fusion (ΔH) of the acid-modified polyolefin is preferably in the range of 5J/g~60J/g. The range of 10J/g~50J/g is more preferable, and the range of 20J/g~40J/g is the best. By setting it as more than the said lower limit value, the cohesive force originating in a crystal|crystallization can be made favorable, and excellent adhesiveness and solder heat resistance can be exhibited. Moreover, by setting it as below the said upper limit, the stability and fluidity of a solution are excellent, and the workability|operativity at the time of adhering becomes favorable.

The production method of the acid-modified polyolefin is not particularly limited, and examples thereof include free radical grafting reaction (that is, generating a free radical species on the polymer that becomes the main chain, and using the free radical species as a polymerization initiation point to make the Graft polymerization of saturated carboxylic acid and acid anhydride), etc.

＜Acid-modified polystyrene resin＞ In the present invention, an acid-modified polystyrene resin can be desirably used as the acid-modified resin. The acid-modified polystyrene resin is not limited, and is preferably a homopolymer of an aromatic vinyl compound or a copolymer mainly composed of a block and/or random structure of an aromatic vinyl compound and a conjugated diene compound and Its hydride is modified by unsaturated carboxylic acid. The aromatic vinyl compound is not particularly limited, and examples include: styrene, tertiary butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylbenzene Ethylene, N,N-diethyl-p-aminoethylstyrene, vinyltoluene, p-tertiary butylstyrene, etc. Moreover, examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, and the like. Specific examples of copolymers of these aromatic vinyl compounds and conjugated diene compounds include: styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer Copolymer (SEPS), Styrene-Ethylene-Ethylene·Propylene-Styrene Block Copolymer (SEEPS), etc.

＜Acid-modified cycloolefin polymer＞ In the present invention, an acid-modified cycloolefin polymer can also be used as the acid-modified resin. Acid-modified cyclic olefin polymers are obtained by introducing carboxyl groups into cyclic olefin polymers by acid modification. For cyclic olefin polymers, homopolymers (COP) made of only one type of cyclic olefin monomers, or Copolymers (COC) composed of one or more cycloolefin monomers and comonomers can be used.

The aforementioned cycloolefin monomers include, for example: bicyclic bodies such as norcamphene and norcamdiene; tricyclic bodies such as dicyclopentadiene and dihydroxypentadiene; tetracyclic bodies such as tetracyclododecene; cyclopentadiene and the like; Pentacyclic bodies such as diene trimers; heptcyclic bodies such as tetracyclopentadiene; or alkyl (methyl, ethyl, propyl, butyl, etc.) etc.) substituents, alkylene (ethylene, etc.) substituents, aryl (phenyl, tolyl, naphthyl, etc.) substituents, etc. Among them, the norcamphene-based monomer selected from the group consisting of norbornene, tetracyclododecene, or their alkyl-substituted products is particularly preferable.

Also, the above-mentioned comonomer may be any monomer that can be copolymerized with the above-mentioned cycloolefin monomer, and is preferably an ethylenic monomer, for example. Examples of ethylenic monomers include α-olefins such as ethylene, propylene, 1-butene, and 1-hexene, isobutylene, and the like. The ethylenic monomer may be linear or branched.

The monomer component constituting the acid-modified cycloolefin polymer is preferably at least 50% by mass of the aforementioned cycloolefin monomer, more preferably at least 60% by mass of the aforementioned cycloolefin monomer. When the cycloolefin monomer accounts for 50% by mass or more of the total monomer components, the heat resistance of the solder will be improved. There are no special restrictions on the polymerization method, polymerization conditions, etc. when the monomer components are polymerized, and they can be set appropriately according to the usual method.

<Compound A> The compound A in this invention is a compound which has a terminal unsaturated hydrocarbon group and whose 5% weight loss temperature is 260 degreeC or more. By having a terminal unsaturated hydrocarbon group, it is possible to increase the crosslink density and improve solder heat resistance by reaction with the compound B described later. Also, since no hydroxyl group that deteriorates the dielectric properties will be produced after the reaction, an adhesive with excellent dielectric properties can be produced. When there are two or more terminal unsaturated hydrocarbon groups in one molecule, it is preferable because the crosslink density can be further increased. Here, the terminal unsaturated hydrocarbon group refers to, for example, a group having a CH ₂ =C structure such as a vinyl group, a vinylidene group, or an allyl group, an acrylic group, a methacrylic group, and a styryl group.

The 5% weight loss temperature of Compound A must be 260°C or higher. It is preferably above 270°C, more preferably above 280°C, and even more preferably above 290°C. When the 5% weight reduction temperature falls above the above-mentioned value, even at a temperature exceeding the melting point of the solder, no appearance defect occurs, and soldering can be performed.

Compound A preferably has an aromatic ring structure or an alicyclic structure as a structural unit. By having an aromatic ring structure or an alicyclic structure as a structural unit, solder heat resistance can be improved and dielectric properties are also excellent. Among them, it is preferable to have an aromatic ring structure or an alicyclic structure as the skeleton of compound A, and it is preferably polyphenylene ether or phenolic resin. Specific examples of polyphenylene ethers having terminal unsaturated hydrocarbon groups include SA-9000 from SABIC and OPE-2St from Mitsubishi Gas Chemical. Moreover, the phenolic resin which has a terminal unsaturated hydrocarbon group can illustrate Resitop FTC-809AE of Qunyei Chemical Industry Co., Ltd.

The number average molecular weight of compound A is preferably 500 or more, more preferably 1000 or more. Also, it is preferably 100,000 or less, more preferably 10,000 or less. When it is in the said range, the solubility to a solvent is favorable, and a uniform adhesive coating film can be formed.

The content of compound A in the adhesive composition of the present invention is preferably at least 1 part by mass, more preferably at least 5 parts by mass, and even more preferably at least 10 parts by mass, based on 100 parts by mass of the acid-modified resin. Moreover, it is preferably at most 100 parts by mass, more preferably at most 70 parts by mass, and even more preferably at most 50 parts by mass. When it is in the said range, it can have both excellent adhesiveness and solder heat resistance.

<Compound B> The compound B in this invention is a compound which has an epoxy group and a terminal unsaturated hydrocarbon group. Since it can react with acid-modified resin and polycarbodiimide described later by having an epoxy group, and can react with compound A by having a terminal unsaturated hydrocarbon group, the crosslink density between these compounds can be further increased , can achieve excellent solder heat resistance. Here, the terminal unsaturated hydrocarbon group refers to, for example, a group having a CH ₂ =C structure such as a vinyl group, a vinylidene group, or an allyl group, an acrylic group, a methacrylic group, and a styryl group.

Compound B preferably has a ring structure. When compound B has a ring structure, heat resistance can be improved and dielectric properties are also excellent. If the ring structure of the compound B is an aromatic ring structure or an isocyanuric acid ring structure, it is preferable from the viewpoint of heat resistance. Specific examples of such compound B include diallyl monoglycidyl isocyanurate and dieglycidyl monoallyl isocyanurate. By using them, the crosslink density can be increased and the solder heat resistance can be improved.

The molecular weight of compound B is preferably 500 or less. It is better to be below 400. When the molecular weight falls below the above-mentioned value, the solubility to the solvent and the reactivity of compound A, acid-modified resin, and polycarbodiimide can be improved, and the crosslink density can be increased to improve solder heat resistance.

The content of compound B in the adhesive composition of the present invention is preferably at least 0.1 part by mass, more preferably at least 0.5 part by mass, and even more preferably at least 1 part by mass, based on 100 parts by mass of the acid-modified resin. Moreover, it is preferably at most 50 parts by mass, more preferably at most 30 parts by mass, and even more preferably at most 20 parts by mass. When it is in the said range, it can have both excellent adhesiveness and solder heat resistance. Also, the content of the compound B is preferably set to 1 equivalent or more of the terminal unsaturated hydrocarbon group relative to the terminal unsaturated hydrocarbon group of the compound A. By setting it to 1 equivalent or more, the crosslink density can be increased and excellent solder heat resistance can be exhibited.

＜Adhesive composition＞ The adhesive composition of the present invention is an adhesive composition comprising an acid-modified resin, compound A and compound B. Here, compound A and compound B are the following compounds, respectively. Compound A: A compound having a terminal unsaturated hydrocarbon group and having a 5% weight reduction temperature of 260°C or higher Compound B: Compound with epoxy group and terminal unsaturated hydrocarbon group By reacting the terminal unsaturated hydrocarbon groups of compound A and compound B, hardening can be carried out without generating hydroxyl groups that deteriorate the dielectric properties, so excellent solder heat resistance and dielectric properties can be achieved at the same time.

The relative dielectric constant (εc) of the adhesive composition of the present invention is preferably 2.7 or less at a frequency of 10 GHz. It is more preferably below 2.6, and even more preferably below 2.3. The lower limit is not particularly limited, and is practically 2.0. Also, the relative permittivity (εc) in the entire frequency range of 1 GHz to 60 GHz is preferably 2.7 or less, more preferably 2.6 or less, and even more preferably 2.3 or less.

The dielectric loss tangent (tanδ) of the adhesive composition of the present invention at a frequency of 10 GHz is preferably 0.003 or less. It is more preferably not more than 0.0025, and more preferably not more than 0.002. The lower limit is not particularly limited, but is practically 0.0001 or more. Also, the dielectric loss tangent (tan δ) in the entire frequency range of 1 GHz to 60 GHz is preferably not more than 0.003, more preferably not more than 0.0025, and even more preferably not more than 0.002.

＜Free Radical Generator＞ The adhesive composition of the present invention also preferably contains a free radical generator. The adhesive composition of the present invention can react compound A and compound B by heating, but by using free radicals generated by a free radical generator, the terminal unsaturated hydrocarbon groups of compound A and compound B can be efficiently made to interact with each other Reacting and increasing the crosslinking density can improve the heat resistance and dielectric properties of the solder. The free radical generator is not particularly limited, and an organic peroxide is preferably used. Organic peroxides are not particularly limited, and examples include: bis(tertiary butyl) peroxyphthalate, tertiary butyl hydroperoxide, dicumyl peroxide, benzoyl peroxide, and benzoic acid peroxide Tertiary butyl ester, tertiary butyl peroxy-2-ethylhexanoate, tertiary butyl peroxytrimethyl acetate, methyl ethyl ketone peroxide, di(tertiary butyl) peroxide, lauryl peroxide, Peroxides such as 2,5-dimethyl-2,5-bis(tertiary butylperoxy)hexane; azonitriles such as azobisisobutyronitrile and azobisisopropionitrile, etc.

The 1-minute half-life temperature of the free radical generating agent used in the present invention is preferably above 140°C. By setting it above 140°C, it is possible to prevent the solvent of the adhesive composition varnish from volatilizing and the free radical reaction to start when the adhesive sheet is produced, and to exhibit excellent adhesiveness.

The blending amount of the radical generator in the adhesive composition of the present invention is preferably at least 0.1 part by mass, more preferably at least 1 part by mass, based on 100 parts by mass of compound A. Moreover, it is preferably at most 50 parts by mass, more preferably at most 20 parts by mass. By setting it within the above-mentioned range, it is possible to adjust to an optimum cross-linking density and achieve both adhesiveness and solder heat resistance.

＜Polycarbodiimide＞ The adhesive composition of the present invention may contain polycarbodiimide. The polycarbodiimide is not particularly limited as long as it has two or more carbodiimide bonds in the molecule. By using polycarbodiimide, the acid-modified polystyrene elastomer, the epoxy group of Compound B and the carbodiimide bond can react and improve heat resistance and adhesiveness.

In the adhesive composition of the present invention, the content of polycarbodiimide is preferably 1 part by mass or more, more preferably 3 parts by mass or more, based on 100 parts by mass of the acid-modified resin. By setting it as more than the said lower limit, a crosslink density can be improved and solder heat resistance can be made favorable. Moreover, it is preferably at most 20 parts by mass, more preferably at most 10 parts by mass. Excellent solder heat resistance and low dielectric properties can be exhibited by setting it below the said upper limit. That is, by setting it in the said range, the adhesive composition which has excellent solder heat resistance and low dielectric property can be obtained.

＜Epoxy resin＞ The adhesive composition of the present invention may contain an epoxy resin different from compound B. The epoxy resin used in the present invention is not particularly limited as long as it has epoxy groups in its molecule, but it is preferably one with two or more epoxy groups in its molecule. It is not particularly limited, and can be selected from biphenyl type epoxy resin, naphthalene type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, alicyclic ring Oxygen resin, dicyclopentadiene type epoxy resin, tetraglycidyl diaminodiphenylmethane, triglycidyl p-aminophenol, tetraglycidyl diaminomethylcyclohexanone, N , at least one selected from the group consisting of N,N',N'-tetraglycidyl-m-xylylenediamine, and epoxy-modified polybutadiene. N,N,N',N'-tetraepoxypropyl m-xylylenediamine, biphenyl type epoxy resin, novolac type epoxy resin, dicyclopentadiene type epoxy resin or epoxy modified polybutadiene. N,N,N',N'-tetraepoxypropyl-m-xylylenediamine is more preferable, which can show excellent adhesiveness.

In the adhesive composition of the present invention, the content of the epoxy resin is preferably at least 0.1 part by mass, more preferably at least 0.5 part by mass, and even more preferably at least 1 part by mass, based on 100 parts by mass of the acid-modified resin. By setting it as more than the said lower limit, sufficient hardening effect can be acquired, and excellent adhesiveness and solder heat resistance can be exhibited. Moreover, it is preferably at most 10 parts by mass, more preferably at most 5 parts by mass. Pot life characteristics and low dielectric characteristics can be made favorable by setting it below the said upper limit. That is, by setting it within the above-mentioned range, an adhesive composition having adhesiveness, solder heat resistance, and pot life characteristics and excellent low dielectric characteristics can be obtained.

The adhesive composition of the present invention may further contain an organic solvent. The organic solvent used in the present invention is not particularly limited as long as it dissolves the acid-modified resin, compound A, and compound B. Specifically, for example: aromatic hydrocarbons such as benzene, toluene, and xylene; aliphatic hydrocarbons such as hexane, heptane, octane, and decane; cyclohexane, cyclohexene, methylcyclohexane, Alicyclic hydrocarbons such as ethylcyclohexane; Halogenated hydrocarbons such as trichlorethylene, dichloroethylene, chlorobenzene, chloroform, etc.; Methanol, ethanol, isopropanol, butanol, pentanol, hexanol, propanediol, phenol, etc. Alcohol-based solvents; ketone-based solvents such as acetone, methyl isobutyl ketone, methyl ethyl ketone, pentanone, hexanone, cyclohexanone, isophorone, acetophenone, etc.; methyl celluloid, ethyl celluloid, etc. Celluloid; methyl acetate, ethyl acetate, butyl acetate, methyl propionate, butyl formate and other ester solvents; ethylene glycol mono-n-butyl ether, ethylene glycol monoisobutyl ether, ethylene glycol mono Glycol ether solvents such as tertiary butyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol mono-isobutyl ether, triethylene glycol mono-n-butyl ether, tetraethylene glycol mono-n-butyl ether, etc., can be used These are used 1 type or in combination of 2 or more types. In particular, considering the working environment and dryness, methylcyclohexane and toluene are preferable.

The organic solvent is preferably in the range of 100 to 1000 parts by mass with respect to 100 parts by mass of the acid-modified resin. By setting it to more than the said lower limit, it will become a liquid and make pot life characteristics favorable. Moreover, it is advantageous in terms of manufacturing cost and transportation cost by setting it below the said upper limit.

In addition, the adhesive composition of the present invention may further contain other components as needed. Specific examples of such components include flame retardants, tackifiers, fillers, and silane coupling agents.

＜Flame retardant＞ In the adhesive composition of the present invention, a flame retardant may also be blended as needed. Examples of the flame retardant include bromine-based, phosphorus-based, nitrogen-based, and hydroxide metal compounds. Among them, phosphorus-based flame retardants are ideal, and well-known phosphorus flame retardants such as phosphoric acid esters (such as trimethyl phosphate, triphenyl phosphate, tricresyl phosphate, etc.), phosphates (such as aluminum hypophosphite, etc.), phosphazene, etc. can be used. Department of flame retardants. These may be used alone or in any combination of two or more. When a flame retardant is contained, it is preferable to contain the flame retardant in the range of 1 to 200 parts by mass, more preferably in the range of 5 to 150 parts by mass, with respect to the total of 100 parts by mass of the acid-modified resin, compound A, and compound B. The range of 10-100 parts by mass is the best. By setting it within the aforementioned range, flame retardancy can be exhibited while maintaining adhesiveness, solder heat resistance, and electrical characteristics.

＜Tackifier＞ In the adhesive composition of the present invention, a tackifier may also be blended as needed. Tackifiers include: polyterpene resins, rosin-based resins, aliphatic petroleum resins, alicyclic petroleum resins, copolymerized petroleum resins, styrene resins, and hydrogenated petroleum resins, etc., in order to improve the bonding strength. And use. These may be used alone or in any combination of two or more. When a tackifier is included, it is preferable to contain the tackifier in the range of 1 to 200 parts by mass, more preferably in the range of 5 to 150 parts by mass, with respect to the total of 100 parts by mass of the acid-modified resin, compound A, and compound B. The range of 10-100 parts by mass is the best. By setting it within the aforementioned range, the effect of the tackifier can be exhibited while maintaining adhesiveness, solder heat resistance, and electrical characteristics.

<Filler> In the adhesive composition of the present invention, a filler may also be blended as needed. Examples of organic fillers include powders of heat-resistant resins such as polyimide, polyamideimide, fluororesin, and liquid crystal polyester. In addition, examples of inorganic fillers include silicon dioxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), tantalum oxide (Ta ₂ O ₅ ), zirconium oxide (ZrO ₂ ), nitride Silicon (Si ₃ N ₄ ), boron nitride (BN), calcium carbonate (CaCO ₃ ), calcium sulfate (CaSO ₄ ), zinc oxide (ZnO), magnesium titanate (MgO･TiO ₂ ), barium sulfate (BaSO ₄ ), organic bentonite (bentonite), clay, mica, aluminum hydroxide, magnesium hydroxide, etc. Among them, silicon dioxide is preferable in consideration of the ease of dispersion and the effect of improving heat resistance.

Silicon dioxide is generally known as hydrophobic silicon dioxide and hydrophilic silicon dioxide. Here, in terms of imparting moisture absorption resistance, dimethyldichlorosilane, hexamethyldisilazane, octylsilane, etc. are used. Hydrophobic silica after treatment is preferred. When silicon dioxide is blended, the blending amount is preferably 0.05 to 30 parts by mass relative to 100 parts by mass of the total of the acid-modified resin, compound A, and compound B. Further heat resistance can be exhibited by setting it as more than the said lower limit. Moreover, by setting it as below the said upper limit, poor dispersion|distribution of silica and an excessively high solution viscosity can be suppressed, and workability|operativity can be made favorable.

＜Silane coupling agent＞ In the adhesive composition of the present invention, a silane coupling agent may also be blended as needed. It is ideal for the properties of adhesion to metal and heat resistance to be improved by blending a silane coupling agent. The silane coupling agent is not particularly limited, and examples thereof include those having an unsaturated group, those having an epoxy group, and those having an amine group. Among them, considering heat resistance, γ-glycidoxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, β-(3,4 A silane coupling agent having an epoxy group such as epoxycyclohexyl)ethyltriethoxysilane is more preferable. When a silane coupling agent is blended, the blending amount is preferably 0.5 to 20 parts by mass relative to 100 parts by mass of the total of the acid-modified resin, compound A, and compound B. By setting it in the said range, solder heat resistance and adhesiveness can be improved.

＜Laminated body＞ The laminated system of the present invention is one in which the adhesive composition is laminated on the base material (two-layer laminate of the base material/adhesive layer), or one in which the base material is more closely bonded (the base material/adhesive layer) layer/substrate 3-layer laminate). Here, the adhesive layer refers to a layer of the adhesive composition obtained by applying the adhesive composition of the present invention to a substrate and drying it. The laminate of the present invention can be obtained by applying the adhesive composition of the present invention to various substrates according to the usual method, drying them, and laminating other substrates.

＜Substrate＞ In the present invention, the substrate is not particularly limited as long as it can be coated with the adhesive composition of the present invention and dried to form an adhesive layer. Examples include: resin substrates such as film-like resins; metal plates, Metal substrates such as metal foil; paper, etc.

Examples of the resin substrate include polyester resin, polyamide resin, polyimide resin, polyamideimide resin, liquid crystal polymer, polyphenylene sulfide, parapolystyrene, polyolefin resin, and Fluorine resin, etc. It is preferably a film-like resin (hereinafter also referred to as a base film layer).

Any known conductive material that can be used in circuit boards can be used as the metal base material. Examples of materials include various metals such as SUS, copper, aluminum, iron, steel, zinc, and nickel, and respective alloys, plating, and metals treated with other metals such as zinc or chromium compounds. It is preferably metal foil, more preferably copper foil. The thickness of the metal foil is not particularly limited, and it is preferably at least 1 μm, more preferably at least 3 μm, and even more preferably at least 10 μm. Also, it is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. When the thickness is too thin, it may be difficult to obtain satisfactory electrical performance of the circuit. On the other hand, when the thickness is too thick, the processing efficiency at the time of circuit production may be reduced. Metal foil is usually provided in roll form. The form of the metal foil used when manufacturing the printed wiring board of this invention is not specifically limited. When using the strip-shaped metal foil, the length is not particularly limited. Also, the width is not particularly limited, and is preferably about 250 to 500 cm. The surface roughness of the substrate is not particularly limited, but it is preferably 3 μm or less, more preferably 2 μm or less, and even more preferably 1.5 μm or less. Also, practically, it is preferably at least 0.3 μm, more preferably at least 0.5 μm, and even more preferably at least 0.7 μm.

Examples of paper include high-quality paper, kraft paper, roll paper, cellophane, and the like. Moreover, as a composite material, a glass epoxy resin etc. can be illustrated.

Considering the adhesion and durability of the adhesive composition, the base material should be polyester resin, polyamide resin, polyimide resin, polyamide imide resin, liquid crystal polymer, polyphenylene sulfide , Parallel polystyrene, polyolefin-based resin, fluorine-based resin, SUS steel plate, copper foil, aluminum foil, or glass epoxy resin.

＜Adhesive sheet＞ In the present invention, the adhesive sheet refers to a laminate formed by laminating the aforementioned laminated body and the release base material with an adhesive composition. Specific structural aspects include: laminate/adhesive layer/release substrate, or release substrate/adhesive layer/laminate/adhesive layer/release substrate. By laminating the release substrate, it will function as a protective layer for the substrate. Also, by using the release base material, the release base material can be released from the adhesive sheet, and the adhesive layer can be transferred to another base material.

The adhesive sheet of the present invention can be obtained by applying the adhesive composition of the present invention to various laminates according to a conventional method and drying them. In addition, after drying, if the release substrate is attached to the adhesive layer, it can be wound up without causing off-set to the substrate, and the workability is excellent. At the same time, because the adhesive layer is protected, Therefore, it has excellent preservation and is easy to use. In addition, after coating and drying on the release base material, another release base material may be attached, or the adhesive layer itself may be transferred to another base material if necessary.

＜Release base material＞ The release base material is not particularly limited, for example: on both sides of high-quality paper, kraft paper, paper rolls, cellophane, etc., a coating layer of clay, polyethylene, polypropylene and other filling agents is provided, and then coated on each Coated with polysiloxane-based, fluorine-based, or alkyd-based mold release agents on the cloth layer. In addition, various olefin films such as polyethylene, polypropylene, ethylene-α-olefin copolymer, propylene-α-olefin copolymer, etc., and coating the above-mentioned release film on a film such as polyethylene terephthalate can also be mentioned. Formed by molding agent. Considering the release force of the release base material and the adhesive layer, polysiloxane will have adverse effects on the electrical properties, etc., it is advisable to perform polypropylene filling treatment on both sides of high-quality paper and use alkyd system on it Formed with a mold release agent, or with an alkyd-based mold release agent on polyethylene terephthalate.

In addition, the method of coating the adhesive composition of the present invention on the substrate is not particularly limited, and examples thereof include: compost coating, reverse roll coating, and the like. Alternatively, an adhesive layer can also be provided on the rolled copper foil or polyimide film as the constituent material of the printed wiring board by direct or transfer printing as needed. The thickness of the dried adhesive layer can be appropriately changed according to the needs, and is preferably in the range of 5-200 μm. Sufficient adhesive strength can be obtained by setting the adhesive film thickness to 5 μm or more. Also, by setting the thickness to 200 μm or less, the amount of residual solvent in the drying step can be easily controlled, and swelling is less likely to occur during pressing in the manufacture of printed wiring boards. The drying conditions are not particularly limited, but the residual solvent rate after drying is preferably 1% by mass or less. By setting it as 1 mass % or less, foaming of the residual solvent at the time of pressing a printed wiring board is suppressed, and swelling does not generate|occur|produce easily.

＜Printed Wiring Board＞ The printed wiring board in the present invention includes a laminate formed of a metal foil forming a conductive circuit and a resin base material as a constituent element, and includes, for example, a flexible substrate, a rigid substrate, a package substrate, and the like. A printed wiring board is manufactured by a well-known method, such as a subtractive method, using a metal-clad laminate, for example. The so-called flexible circuit board (FPC), flat cable, tape automatic bonding (TAB ) with circuit boards, etc.

The printed wiring board of the present invention can be provided in any laminated structure that the printed wiring board can adopt. For example, it can be made into a printed wiring board composed of four layers of a base film layer, a metal foil layer, an adhesive layer, and a cover film layer. Also, for example, a printed wiring board composed of five layers of a base film layer, an adhesive layer, a metal foil layer, an adhesive layer, and a cover film layer can be produced.

Moreover, it can also be made into the structure which laminated|stacked 2 or 3 or more said printed wiring boards as needed.

The adhesive composition of the present invention can be ideally used in each adhesive layer of a printed wiring board. In particular, if the adhesive composition of the present invention is used as an adhesive, it is not only compatible with conventionally known polyimide, polyester film, and copper foil that constitute printed wiring boards, but also with low-polarity resin substrates such as LCP. High adhesion, can obtain solder reflow resistance, and the adhesive layer itself has excellent low dielectric properties. Therefore, it is suitable as an adhesive composition for coverlay film, laminated board, copper foil with resin and adhesive sheet.

In the printed wiring board of this invention, arbitrary resin films conventionally used as a base material of a printed wiring board can be used for a base film. The resin of the base film can be exemplified: polyester resin, polyamide resin, polyimide resin, polyamideimide resin, liquid crystal polymer, polyphenylene sulfide, p-polystyrene, polyolefin resin , and fluorine-based resins, etc. In particular, it has excellent adhesion to low-polarity substrates such as liquid crystal polymers, polyphenylene sulfide, polystyrene, and polyolefin resins.

＜Cover film＞ As the cover film, any known insulating film for printed wiring boards can be used. For example, polyimide, polyester, polyphenylene sulfide, polyether sulfide, polyether ether ketone, polyaramid, polycarbonate, polyarylate, polyamideimide, liquid crystal, etc. Films made of various polymers such as polymers, polystyrene, and polyolefin resins. More preferably, it is a polyimide film or a liquid crystal polymer film.

The printed wiring board of the present invention can be manufactured by any known process except for the materials of the above-mentioned layers.

In an ideal embodiment, it is a semi-product manufactured by laminating the adhesive layer on the cover film layer (hereinafter referred to as "cover film side half product"). On the other hand, semi-products (hereinafter referred to as "substrate film-side 2-layer semi-products") in which a metal foil layer is laminated on a base film layer and a desired circuit pattern is formed, or an adhesive layer is laminated on a base film A semi-product formed by laminating a metal foil layer on it and forming a desired circuit pattern (hereinafter referred to as "3.5-layer product on the base film side") (hereinafter referred to as a 2-layer semi-product on the base film side and a 3.5-layer products are collectively referred to as "substrate film side-half products"). A 4-layer or 5-layer printed wiring board can be obtained by laminating the cover film-side half product and base film-side half product obtained in this way.

The half-product of the substrate film can be obtained, for example, by a manufacturing method comprising the following steps: (A) coating the aforementioned metal foil with a solution of the resin that becomes the substrate film and performing initial drying of the coating film; (B) obtaining (A) The laminate of the metal foil and the initially dried coating film is subjected to heat treatment-drying (hereinafter referred to as "heat treatment-desolventization step").

Circuits in the metal foil layer can be formed using known methods. Additive or subtractive methods can be used. It should be the subtraction method.

The obtained substrate film side half can be directly used for lamination with the cover film side half, and can also be pasted with a release film for storage before being used for lamination with the cover film side half.

The cover film side half product is manufactured by coating the adhesive on the cover film, for example. The cross-linking reaction in the coated adhesive can be carried out as needed. In an ideal embodiment, the adhesive layer is semi-hardened.

The obtained cover film side half can be directly used for lamination with the base film side half, and can also be pasted with a release film for storage before being used for lamination with the base film side half.

The half-product on the base film side and the half-product on the cover film side are respectively stored in the form of a roll, for example, and then bonded together to manufacture a printed wiring board. Arbitrary methods can be used for the bonding method, for example, bonding can be performed using a press, a roll, or the like. Moreover, both can also be bonded together, heating by methods, such as a heating press or a heating roll apparatus.

When the side half of the reinforcing material is a soft and windable reinforcing material such as polyimide film, it is ideal to manufacture it by coating the reinforcing material with an adhesive. In addition, in the case of a hard and unwindable reinforcing plate such as a metal plate such as SUS or aluminum, or a plate made by hardening glass fiber with epoxy resin, it can be bonded by applying it to the release substrate in advance. It is ideal to manufacture by transfer coating with agent. Moreover, the crosslinking reaction in the adhesive agent after coating can be implemented as needed. In an ideal embodiment, the adhesive layer is semi-hardened.

The obtained reinforcing material side half can be directly used for lamination to the back of the printed wiring board, and can also be pasted with a release film for storage before being used for lamination with the base film side half.

The base film-side half product, the cover film-side half product, and the reinforcement material-side half product are all laminates for printed wiring boards in the present invention. [Example]

Hereinafter, the present invention will be described concretely with reference to examples. In addition, in this Example and a comparative example, let it represent mass parts only by expressing in a part.

<Physical property evaluation method> (Measurement of acid value) The acid value (equivalent/10 ⁶ g) in the present invention is obtained by dissolving the acid-modified resin in toluene and titrating it with a methanol solution of sodium methoxide using phenolphthalein as an indicator.

(number average molecular weight (Mn)) The number average molecular weight in the present invention is to utilize Shimadzu Co., Ltd. to make gel permeation chromatography (hereinafter referred to as GPC, standard substance: polystyrene resin, mobile phase: tetrahydrofuran, column: Shodex KF-802+KF-804L + KF-806L, column temperature: 30°C, flow rate: 1.0ml/min, detector: RI detector).

(Measurement of melting point and heat of fusion) The melting point and heat of fusion in the present invention are determined by using a differential scanning calorimeter (hereinafter referred to as DSC, manufactured by TA Instruments Japan, Q-2000) to heat up and melt at a speed of 20°C/min, and after cooling to resin, heat up again The values measured from the peak temperature and area of the melting peak during melting.

(Determination of 5% weight loss temperature) Measurement was performed using a differential thermal-thermogravimetric simultaneous measurement device (Shimadzu Corporation, DTG-60). Let the 5mg sample that has been placed in the aluminum pan be heated up at a rate of 10°C/min in the air environment, and the temperature when it loses 5% of its weight due to thermal decomposition is the 5% weight loss temperature (unit:°C) .

(Relative permittivity (ε _c ) and dielectric loss tangent (tanδ)) The relative permittivity (ε _c ) and dielectric loss tangent (tanδ) of the acid-modified resin were obtained by using Network Analyzer (manufactured by Anritsu Corporation). Resonant cavity perturbation method (resonant cavity perturbation method), measured at a temperature of 23°C and a frequency of 10GHz.

Hereinafter, the manufacture example of the adhesive composition which is the Example of this invention, and the adhesive composition which is a comparative example is illustrated.

Synthesis example of acid-modified polyolefin (c1) Add 100 parts by mass of propylene-butene copolymer ("TAFMER (registered trademark) XM7080" manufactured by Mitsui Chemicals Co., Ltd.) and 150 parts by mass of toluene to a 1L autoclave and 19 parts by mass of maleic anhydride and 6 parts by mass of di(tertiary butyl)peroxide were heated up to 140° C., and then stirred for 3 hours. Then, after cooling the obtained reaction liquid, it poured into the container which put a large amount of methyl ethyl ketone, and resin was precipitated. Then, by centrifuging the liquid containing the resin, the acid-modified propylene-butene copolymer after graft polymerization of maleic anhydride, (poly) maleic anhydride and low molecular weight substances were separated and purified. Then, it was dried under reduced pressure at 70°C for 5 hours, thereby obtaining a maleic anhydride-modified propylene-butene copolymer (c1, acid value 338 equivalents/10 ⁶ g, number average molecular weight 25,000, Tm 80°C, ΔH35J/ g).

As the acid-modified polystyrene resin, the following ones were used. (c2): TUFTEC M1911 (manufactured by Asahi Kasei Co., Ltd.), acid value 37 equivalents/10 ⁶ g, relative permittivity 2.3, dielectric loss tangent 0.0008 (c3): TUFTEC M1913 (manufactured by Asahi Kasei Co., Ltd.), acid value 185 equivalents/10 ⁶ g, relative permittivity 2.3, dielectric loss tangent 0.0008 (c4): TUFTEC M1943 (manufactured by Asahi Kasei), acid value 185 equivalent/10 ⁶ g, relative permittivity 2.3, dielectric loss tangent 0.0008

Synthesis example of acid-modified cyclic olefin polymer (c5) In a 1L high-temperature autoclave, 100 parts by mass of cyclic olefin polymer (manufactured by Nippon Zeon "ZEONEX (registered trademark) RS420"), 150 parts by mass of toluene, and 19 parts by mass of acid anhydride and 6 parts by mass of di(tertiary butyl)peroxide were heated up to 140° C., and then stirred for 3 hours. Then, after cooling the obtained reaction liquid, it poured into the container which put a large amount of methyl ethyl ketone, and resin was precipitated. Then, by centrifuging the liquid containing the resin, the acid-modified cyclic olefin polymer, (poly) maleic anhydride and low-molecular-weight substances after maleic anhydride graft polymerization were separated and purified. Then, it was dried under reduced pressure at 70°C for 5 hours to obtain a maleic anhydride-modified cycloolefin polymer (c5, acid value 339 equivalents/10 ⁶ g, relative permittivity 2.0, dielectric loss tangent 0.0008).

Compound A used the following. (a1): SA-9000 (manufactured by SABIC, polyphenylene ether having a vinyl group, number average molecular weight 1700, 5% weight loss temperature 439°C) (a2): FTC809AE (manufactured by Qunyei Chemical Industry Co., Ltd., phenolic resin with vinyl groups, number average molecular weight 1400, 5% weight reduction temperature 332°C) (a3): PEGDA (manufactured by Sigma-Aldrich, polyethylene glycol diacrylate, weight average molecular weight 700, 5% weight loss temperature 220° C.) (a4): SA-90 (manufactured by SABIC Corporation, polyphenylene ether having a hydroxyl end (with no terminal unsaturated hydrocarbon group), number average molecular weight 1700, 5% weight loss temperature 430°C.)

Compound B used the following. (b1): DA-MGIC (manufactured by Shikoku Chemical Industry Co., Ltd., diallyl monoglycidyl isocyanurate) (b2): MA-DGIC (manufactured by Shikoku Chemical Industry Co., Ltd., monoallyldiglycidyl isocyanurate) (b3): diallyl isocyanurate (manufactured by Tokyo Chemical Industry Co., Ltd.)

Components other than the above are used as follows. TETRAD X: Epoxy resin (manufactured by Mitsubishi Gas Chemical Co., Ltd., glycidylamine type epoxy) PERBUTYL P: free radical generator (manufactured by NOF, bis(1-tertiary butylperoxy-1-methylethyl)benzene, 1-minute half-life temperature 175°C)

<Example 1> The acid-modified polyolefin (c1) obtained in the aforementioned synthesis example was dissolved in methylcyclohexane to prepare a methylcyclohexane varnish with a solid content concentration of 20% by mass. In this methylcyclohexane varnish, (a1) as compound A and (a1) as compound B were blended so as to be 20 parts, 5 parts, and 3 parts, respectively, with respect to 100 parts of acid-modified polyolefin (c1). (b1), and PERBUTYL P to obtain the adhesive composition (S1). Regarding the obtained adhesive composition (S1), respective evaluations of relative permittivity, dielectric loss tangent, peel strength, solder heat resistance, and adhesive sheet flexibility were implemented. The results are shown in Table 1.

<Examples 2~9, Comparative Examples 1~5> Except having changed the kind and compounding quantity of hardening|curing agent etc. as shown in Table 1 and Table 2, it carried out similarly to Example 1, and produced the adhesive agent composition, and implemented each evaluation. The results are described in Table 1 and Table 2.

<Example 10> The acid-modified polystyrene resin (c2) was used as the acid-modified resin, and it was blended as a compound so as to be 20 parts, 5 parts, and 3 parts, respectively, relative to 100 parts of the acid-modified polystyrene resin (c2). (a1) of A, (b1) of compound B, and PERBUTYL P were dissolved in toluene to a solid content concentration of 30% by mass to obtain an adhesive composition (S10). For the obtained adhesive composition (S10), each evaluation of relative permittivity, dielectric loss tangent, peel strength, solder heat resistance, and adhesive sheet flexibility was implemented. The results are shown in Table 1.

<Examples 11~21, Comparative Examples 6~9> Except having changed the types and compounding amounts of each component of the adhesive composition to those shown in Table 1 and Table 2, an adhesive composition was produced in the same manner as in Example 10, and each evaluation was performed. The results are described in Table 1 and Table 2.

<Evaluation of Adhesive Composition> (relative permittivity (ε _c ) and dielectric loss tangent (tanδ)) The adhesive composition was applied to iron fluoride with a thickness of 100 μm so that the thickness after drying was 25 μm. Dragon (registered trademark) sheet, and dried at 130° C. for 3 minutes. Then, after heat treatment at 180° C. for 3 hours to make it harden, the Teflon (registered trademark) sheet was peeled off to obtain an adhesive resin sheet for testing. Thereafter, the obtained test adhesive resin sheet was cut into strips of 8 cm×3 mm as samples to obtain test samples. The relative permittivity (ε _c ) and dielectric loss tangent (tanδ) were measured using a Network Analyzer (manufactured by Anritsu Corporation) under conditions of a temperature of 23° C. and a frequency of 10 GHz by the resonant cavity perturbation method. <Evaluation criteria for relative dielectric constant> ○: 2.4 or less ×: More than 2.4 <Evaluation criteria for dielectric loss tangent> ◎: Less than 0.0020 ○: More than 0.0020 and less than 0.0025 ×: More than 0.0025

(Peel strength (adhesiveness)) The adhesive composition was applied to a polyimide film (manufactured by Kaneka Co., Ltd., APICAL (registered trademark)) with a thickness of 12.5 μm so that the thickness after drying was 25 μm, and dried at 130° C. for 3 minutes. The adhesive film (B stage product) obtained in this way and the rolled copper foil (made by Nippon Steel Chemical & Materials Co., Ltd., espanex series) of 18 micrometers in thickness were bonded together. The bonding system is carried out in such a way that the glossy surface of the rolled copper foil is in contact with the adhesive layer, and is pressed at 170°C for 280 seconds under a pressure of 2 MPa to bond. Then, it heat-processed at 180 degreeC for 3 hours, it hardened|cured, and the sample for peeling strength evaluation was obtained. Peel strength is measured under the conditions of 25°C, film stretching, stretching speed 50mm/min, and 90°peeling. This test indicates the adhesive strength at room temperature. ＜Evaluation criteria＞ ○: 1.0N/mm or more ×: less than 1.0N/mm

(solder heat resistance) Prepare samples for evaluation by the same method as the above-mentioned peel strength measurement, immerse a 2.0cm×2.0cm sample piece in a solder bath melted at 288°C, and check whether there is any change in appearance such as swelling. ＜Evaluation criteria＞ ◎: No swelling for more than 60 seconds ○: There is swelling in more than 30 seconds and less than 60 seconds ×: There is swelling in less than 10 seconds

(flexibility of adhesive sheet) The adhesive composition was applied to a Teflon (registered trademark) sheet with a thickness of 100 μm so that the thickness after drying was 25 μm, and dried at 130° C. for 3 minutes. Then, the state of the coating film when this sheet|seat was bent 180 degrees was confirmed. ＜Evaluation criteria＞ ○: No crack damage ×: Cracked and damaged

[Table 1] Example number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 twenty one Adhesive composition S1 S2 S3 S4 S5 S6 S7 S8 S9 S10 S11 S12 S13 S14 S15 S16 S17 S18 S19 S20 S21 acid modified resin c1 100 100 100 100 100 100 100 100 100 c2 100 100 100 100 100 100 100 100 100 c3 100 c4 100 c5 100 Compound A a1 20 20 10 30 20 20 20 20 20 20 20 20 20 10 30 20 20 20 20 a2 20 20 a3 a4 Compound B b1 5 5 5 5 2 8 5 5 5 5 5 5 5 5 5 2 8 5 5 b2 5 5 b3 other ingredients TETRAD X PERBUTYL P 3 1 3 3 3 3 3 3 3 1 1 1 1 3 3 3 3 3 3 Evaluation results Relative permittivity ○ 2.1 ○ 2.1 ○ 2.2 ○ 2.3 ○ 2.1 ○ 2.3 ○ 2.2 ○ 2.1 ○ 2.3 ○ 2.2 ○ 2.2 ○ 2.2 ○ 2.2 ○ 2.2 ○ 2.2 ○ 2.3 ○ 2.2 ○ 2.3 ○ 2.2 ○ 2.2 ○ 2.3 Dielectric loss tangent ◎ 0.0007 ◎ 0.0009 ◎ 0.0014 ○ 0.0017 ◎ 0.0012 ○ 0.0018 ○ 0.0018 ◎ 0.0009 ○ 0.0019 ◎ 0.0009 ◎ 0.0011 ◎ 0.0009 ◎ 0.0011 ◎ 0.0016 ◎ 0.0016 ◎ 0.0019 ◎ 0.0014 ○ 0.0022 ○ 0.0022 ◎ 0.0011 ○ 0.0023 Peel strength ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Solder heat resistance ◎ ○ ○ ◎ ◎ ◎ ◎ ◎ ○ ◎ ○ ○ ○ ○ ○ ◎ ◎ ◎ ◎ ◎ ○ Adhesive sheet flexibility ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

[Table 2] Comparative example number 1 2 3 4 5 6 7 8 9 Adhesive composition S22 S23 S24 S25 S26 S27 S28 S29 S30 acid modified resin c1 100 100 100 100 c2 100 100 100 100 c3 c4 c5 Compound A a1 20 20 20 20 20 a2 a3 20 20 a4 20 20 Compound B b1 5 5 5 5 5 b2 b3 5 5 other ingredients TETRAD X 5 5 PERBUTYL P 3 3 3 3 3 3 3 3 3 Evaluation results Relative permittivity ○ 2.1 ○ 2.4 × 2.5 ※ ○ 2.4 ○ 2.2 ○ 2.4 × 2.5 ○ 2.4 Dielectric loss tangent ◎ 0.0007 × 0.0028 × 0.0035 ※ × 0.0030 ◎ 0.0010 × 0.0033 × 0.0040 × 0.0035 Peel strength ○ ○ ○ x ○ ○ ○ ○ ○ Solder heat resistance x x x x x x x x x Adhesive sheet flexibility ○ ○ ○ x ○ ○ ○ ○ ○ ※The coating film of Comparative Example 4 is fragile, and the relative dielectric constant and dielectric loss tangent cannot be measured.

From Table 1 and Table 2, it can be seen that the pot life, dielectric properties, peel strength, solder heat resistance and flexibility of the adhesive sheet of Examples 1-21 are excellent. On the other hand, in Comparative Example 1 and Comparative Example 6, since the compound B did not have an epoxy group, the curing was insufficient and the solder heat resistance was insufficient. In Comparative Example 2 and Comparative Example 7, since the compound B was not included and the epoxy resin was blended, the dielectric properties as the adhesive composition were poor. In Comparative Example 3 and Comparative Example 8, since the compound A did not have a terminal unsaturated hydrocarbon group, the hardening was insufficient and the solder heat resistance was insufficient. Also, the dielectric loss tangent is also high due to the influence of the hydroxyl terminal. In Comparative Example 4, since the acid-modified resin was not contained, the adhesive sheet was fragile, and the peel strength and solder heat resistance were insufficient. Also, since the coating film was fragile, the relative permittivity and dielectric loss tangent could not be measured. In Comparative Example 5 and Comparative Example 9, since the 5% weight loss temperature of Compound A was low, the solder heat resistance was poor. [industrial availability]

The adhesive composition of the present invention has excellent heat resistance and adhesive strength, low relative dielectric constant and dielectric loss tangent, and good flexibility of the adhesive sheet. Therefore, it is useful as an adhesive and an adhesive sheet for printed wiring boards suitable for printed boards (flexible boards, rigid boards, and package boards) in high-frequency regions.

Claims (8)

An adhesive composition comprising acid-modified resin, compound A and compound B; Compound A: a compound with a terminal unsaturated hydrocarbon group and a 5% weight loss temperature of 260°C or higher; Compound B: a compound having an epoxy group and a terminal unsaturated hydrocarbon group. The adhesive composition according to claim 1, wherein the acid-modified resin contains at least one resin selected from acid-modified polyolefins, acid-modified polystyrene resins, and acid-modified cycloolefin polymers. The adhesive composition according to claim 1 or 2, wherein the compound A is a compound having an aromatic ring structure or an alicyclic structure as a structural unit. The adhesive composition according to claim 1 or 2, wherein the compound A is polyphenylene ether or phenolic resin with terminal unsaturated hydrocarbon groups. The adhesive composition according to claim 1 or 2, wherein the compound B is a compound having an isocyanuric acid ring. An adhesive sheet having an adhesive layer made of the adhesive composition according to any one of claims 1 to 5. A laminate having an adhesive layer made of the adhesive composition according to any one of claims 1 to 5. A printed wiring board including the laminate according to claim 7 as a constituent element.