JP2023023334A - Resin composition containing curable high-molecular-weight compound - Google Patents

Abstract

To provide a composition to be a cured object which has flexibility, has high adhesiveness to low-roughness copper foil, is low in permittivity and dielectric dissipation factor, and has a high glass transition temperature.SOLUTION: A resin composition comprises: a high-molecular-weight compound represented by formula (1); an end-modified polyimide resin, which is a product from the reaction between a polyimide resin and a maleic anhydride; and a radical initiator.SELECTED DRAWING: None

Description

The present invention can be easily formed into a film by a method of casting a solution into a base material, and by using it together with a radical initiator, a heat or photo-curing reaction is possible, and the cured product has dielectric properties. , and relates to a resin composition having excellent adhesiveness and heat resistance.

A phenoxy resin is a polymer compound having a very large molecular weight obtained by polymerizing a bifunctional epoxy resin and a bifunctional phenol compound. By adding this phenoxy resin, general epoxy resin compositions and radically polymerizable compositions can be made into films, so it is used in a wide range of fields as an important component of film adhesives. In the electrical and electronic fields, it is used for interlayer insulating layers of printed wiring boards and resin-coated copper foils.

A cured product of a resin composition to which a phenoxy resin is added has excellent adhesiveness and film-forming ability, but has low heat resistance. 03), and it cannot be used for electronic devices with high signal response speed in recent years. Polymer fluorine compounds such as polytetrafluoroethane (PTFE) (Patent Document 1) and liquid crystal polymers (Patent Document 2) are generally known as resins having excellent dielectric properties, but these resins are different from other resins. compatibility is extremely low, and adhesion is also insufficient. In Patent Document 3, a random copolymer of a monomer having 70% by weight or less of one ethylenically unsaturated group and a (meth)acrylate having 30% by weight or more of one or more aliphatic hydroxyl groups A curable polymer compound obtained by esterifying a monomer having one or more ethylenically unsaturated groups and one carboxyl group to an aliphatic hydroxyl group of is described. In a follow-up test, the cured product of the curable polymer compound obtained by the structural formula of the same document had a dielectric loss tangent of around 0.005 even at 10 GHz. is not fully satisfied.

JP 2005-001274 A JP 2014-060449 A JP-A-10-017812

The present invention has been made in view of the above points, and has sufficient flexibility to be formed into a film, high adhesion to low-roughness copper foil, low dielectric constant and dielectric loss tangent, and glass. An object of the present invention is to provide a composition that becomes a cured product having a high transition temperature.

As a result of intensive studies, the present inventors have found that a resin composition containing a polymer compound with a specific structure, a terminal-modified polyimide resin with a specific structure, and a radical initiator can solve the above problems, and completed the present invention. let me
That is, the present invention
(1) Formula (1) below

(Wherein, R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group; m and n are the average number of repeating units and are each independently in the range of 1 to 2,000.) A polymer compound, a terminal-modified polyimide resin that is a reaction product of an aliphatic diamine and an aliphatic or aromatic acid dianhydride and is a reaction product of a polyimide resin having amino groups at both ends and maleic anhydride, and a resin composition containing a radical initiator,
(2) A film adhesive made of the resin composition described in (1) above, and (3) A cured product of the resin composition described in (1) or a cured film adhesive described in (2) above. ,
Regarding.

The resin composition of the present invention can be cured by applying heat or light energy, and the cured product exhibits excellent dielectric properties, adhesion, heat resistance and water resistance.

Embodiments of the present invention are described below.
The polymer compound represented by the formula (1), which is an essential component of the resin composition of the present invention, is a random copolymer of (meth)acrylate having a phenolic hydroxyl group and styrene (hereinafter simply "copolymer" It is a dehydrochlorination reaction product of an intermediate raw material and (meth)acrylic acid chloride. The synthesis method described above is merely an example, and the method for synthesizing the polymer compound represented by formula (1) is not limited to this.
First, the copolymer (intermediate raw material) will be described.

The (meth)acrylate having a phenolic hydroxyl group, which is a raw material for the copolymer, is not particularly limited as long as it is a compound having a phenolic hydroxyl group and a (meth)acryloyl group in one molecule, such as 4-hydroxyphenyl methacrylate. , 2-hydroxyphenyl methacrylate, 3-hydroxyphenyl methacrylate, 4-hydroxyphenyl acrylate, 2-hydroxyphenyl acrylate, 3-hydroxyphenyl acrylate and the like, with 4-hydroxyphenyl methacrylate being preferred.
In this specification, the term "(meth)acrylate" means both "acrylate and methacrylate".

The following formula (2) is a structural formula of a random copolymer of hydroxyphenyl (meth)acrylate and styrene, and R ₁ , m and n in formula (2) are R ₁ , m and n in formula (1). has the same meaning as n. As the polymer compound represented by formula (1) contained in the resin composition of the present invention (polymer compound having a structure represented by formula (1)), a copolymer represented by the following formula (2) A polymer compound that uses coalescence as an intermediate raw material is preferred.

A method for copolymerizing (meth)acrylate having a phenolic hydroxyl group with styrene is not particularly limited as long as it is a known copolymerization method, and examples thereof include bulk polymerization, solution polymerization, emulsion polymerization and suspension polymerization.
Solvents usable for solution polymerization include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, propylene glycol monomethyl ether acetate, N-methylpyrrolidone, N,N-dimethylformamide and γ-butyrolactone. be done. Water and a surfactant are usually used for emulsion polymerization and suspension polymerization, and the copolymerization reaction is carried out in a state in which the raw material components are emulsified or suspended in water.

The copolymerization reaction may be radical polymerization, cationic polymerization or anionic polymerization. In the case of radical polymerization, it is preferable to use a radical polymerization initiator. Specific examples of radical polymerization initiators include 2,2′-azobisisobutyronitrile, 2,2′-azobis(2-methylbutyronitrile), 2,2′-azobis(2,4-dimethylvalero nitrile), 1,1′-azobis(cyclohexane-1-carbonitrile, 2,2′-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, hydrogen peroxide, di-t-butyl Peroxide, dicumyl peroxide, benzoyl peroxide and the like.
The amount of the radical polymerization initiator to be blended is usually 0.001 to 5 parts by mass per 100 parts by mass of the raw material component of the copolymer. The polymerization temperature is usually 50 to 250°C, preferably 60 to 200°C, and the polymerization time is usually 0.5 to 30 hours, preferably 1 to 20 hours. The radical polymerization reaction is preferably carried out in a nitrogen gas atmosphere in order to prevent polymerization inhibition by oxygen in the air.

Specific examples of cationic _{polymerization} initiators include inorganic acids such as sulfuric acid and hydrochloric acid, organic acids such as _CF3COOH and _CCl3COOH , and super strong acids such as _CF3SO3H and _HClO4 . Specific examples of anionic polymerization initiators include butyllithium, Na-naphthalene complexes, alkali metals, alkyllithium compounds, sodium amides, Grignard reagents and lithium alkoxides. However, ionic initiators used in cationic polymerization and anionic polymerization may remain in the copolymer even after the polymerization reaction and adversely affect the dielectric properties and insulation properties. Synthesis of the copolymer to be is preferably carried out by radical polymerization.
The amount of the cationic polymerization initiator or the anionic polymerization initiator to be blended is usually 0.01 to 5 parts by mass with respect to 100 parts by mass of raw material components of the copolymer. The polymerization temperature is usually 40 to 150°C, preferably 50 to 120°C, and the polymerization time is usually 0.5 to 20 hours, preferably 1 to 15 hours.

The number average molecular weight of the copolymer is usually 3,000 to 300,000, preferably 5,000 to 200,000.
In order to obtain a copolymer having a number average molecular weight within the above range, it is preferable to adjust the amount of the initiator used in synthesizing the copolymer to an appropriate amount. The amount of the initiator required to obtain a copolymer having a number average molecular weight within the above range depends on the type of (meth)acrylate having a phenolic hydroxyl group and the (meth)acrylate and styrene having a hydroxyl group used in the copolymerization reaction. Although it cannot be generalized because it depends on the amount of the initiator, it is generally known that a copolymer with a large molecular weight can be obtained by reducing the amount of the initiator. It suffices to select the blending amount of the initiator that allows the polymer to be obtained.

The ratio of the (meth)acrylate having a phenolic hydroxyl group and styrene to be used when synthesizing the copolymer is not particularly limited, but the amount (mass) of styrene used is usually 4 times the mass of the (meth)acrylate having a phenolic hydroxyl group. to 99.5 times, preferably 4.5 to 99.7 times. By setting the ratio of the (meth)acrylate having a phenolic hydroxyl group and styrene used as raw materials of the copolymer to the above range, the cured product exhibits excellent dielectric properties (low dielectric constant and low dielectric loss tangent). A polymer compound is obtained.

The polymer compound used in the present invention includes a phenolic hydroxyl group possessed by the copolymer (this hydroxyl group is a hydroxyl group possessed by the raw material (meth)acrylate having a phenolic hydroxyl group), ) Obtained by dehydrochlorination reaction with the chloride group of acrylic acid chloride.

The ratio of the copolymer and (meth)acrylic acid chloride used in synthesizing the polymer compound used in the present invention is not particularly limited, but if the (meth)acrylic acid chloride is excessive relative to the hydroxyl groups possessed by the copolymer, or If it is insufficient, (meth)acrylic acid chloride remaining unreacted in the polymer compound or hydroxyl groups remaining without reacting with (meth)acrylic acid chloride may adversely affect various properties of the cured product. Therefore, it is preferable to use (meth)acrylic acid chloride in an amount equivalent to the hydroxyl groups possessed by the copolymer.

The reaction between the copolymer and (meth)acrylic acid chloride may be carried out by adding (meth)acrylic acid chloride to a solution of the copolymer in an organic solvent while stirring. The organic solvent that can be used here is not particularly limited as long as it can dissolve the copolymer and (meth)acrylic acid chloride. The copolymer solution may be used as it is. The concentration of the copolymer solution to be reacted with (meth)acrylic acid chloride is usually 10 to 90 mass %, preferably 20 to 80 mass %. The reaction temperature is generally 30 to 120°C, preferably 40 to 110°C, and the reaction time is generally 0.5 to 4 hours, preferably 1 to 3 hours.

Since the reaction between the copolymer and (meth)acrylic acid chloride is a dehydrochlorination reaction, a tertiary amine such as triethylamine or pyridine is added in advance to the reaction solution in order to trap the generated hydrochloric acid and further promote the reaction. It is preferable to add. The amount of the tertiary amine to be used is preferably equimolar to 4-fold mol, more preferably equimolar to 3-fold mol, to (meth)acrylic acid chloride. Hydrochloric acid generated during the reaction precipitates as an amine hydrochloride and can be removed by filtration after the reaction. Excess tertiary amine can be distilled out of the system under heating and reduced pressure after filtration.

In order to prevent the polymerization reaction between (meth)acryloyl groups in the polymer compound used in the present invention and to improve the storage stability of the polymer compound, a polymerization inhibitor may be added to the polymer compound solution after the completion of the synthesis reaction. It is preferable to add a small amount of Specific examples of polymerization inhibitors include hydroquinone, para-methoxyphenol, methylhydroquinone, di-t-butylhydroxytoluene, t-butylhydroquinone, 2-t-butyl-1,4-benzoquinone, 1,4-benzoquinone, 1 ,1-diphenyl-2-picrylhydrazyl free radical, 6-t-butyl-2,4-xylenol, 4-t-butylpyrocatechol, 2,6-di-t-butylphenol, 2,6-di- and t-butyl-p-cresol and phenothiazine.

The range of number average molecular weight of the polymer compound used in the present invention thus obtained is preferably 11,000 to 300,000, more preferably 15,000 to 200,000. If the molecular weight is smaller than the above range, the adhesiveness to the low-roughness copper foil will be low, and if it is larger, the viscosity will increase, making coating difficult.
In addition, the molecular weight in this specification means the value calculated by polystyrene conversion based on the measurement result of GPC.

The resin composition of the present invention contains a radical initiator.
Preferred thermal radical initiators include, for example, benzoyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di(t-butyl peroxide). oxy)hexyne-3, di-t-butyl peroxide, t-butylcumyl peroxide, α,α-bis(t-butylperoxy-m-isopropyl)benzene, 2,5-dimethyl-2,5-di (t-butylperoxy)hexane, dicumyl peroxide, di-t-butylperoxyisophthalate, t-butylperoxybenzoate, 2,2-bis(t-butylperoxy)butane, 2,2-bis Peroxides such as (t-butylperoxy)octane, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, di(trimethylsilyl)peroxide and trimethylsilyltriphenylsilylperoxide are included.

Examples of preferred photoradical initiators include benzoin and its alkyl ethers such as benzoin, benzoin methyl ether and benzoin ethyl ether; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone and 1,1-dichloroacetophenone; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone and 1-chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone and 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one and 2-benzyl-2-dimethyl amino-1-(4-morpholinophenyl)-butanone-1; acylphosphine oxides and xanthones;

The content of the radical initiator in the resin composition of the present invention is a polymer compound, a polyimide resin that is a reaction product of an aliphatic diamine and an aliphatic or aromatic dianhydride and has amino groups at both ends, and an anhydrous Usually 0.1 to 10 parts by weight, preferably 0.1 parts per 100 parts by weight of the total of 100 parts by weight of the resin component such as the terminal-modified polyimide resin which is the reaction product with maleic acid and the radical reactive monomer which is an optional component described later. to 8 parts by mass.

The terminal-modified polyimide resin, which is a reaction product of an aliphatic diamine and an aliphatic or aromatic acid dianhydride used in the present invention and is a reaction product of a polyimide resin having amino groups at both ends and maleic anhydride, It can be obtained by a known method described in Japanese Patent Publication No. 5328006 or the like. Specifically, an aliphatic diamine and an aromatic or aliphatic tetracarboxylic dianhydride are subjected to a dehydration condensation reaction in an organic solvent at a molar ratio in which the aliphatic diamine is excessive using an acid catalyst, It can be obtained by dehydration condensation of an amino group present at the end of the polymer and maleic anhydride, and removing the catalyst by washing with water.

Specific examples of aliphatic diamines include 1,10-diaminodecane; 1,12-diaminododecane; dimer diamine; 1,2-diamino-2-methylpropane; 1,2-diaminocyclohexane; 1,3-diaminopropane; 1,4-diaminobutane; 1,5-diaminopentane; 1,7-diaminoheptane; 1,8-diaminomenthane; 3′-diamino-N-methyldipropylamine; diaminomaleonitrile; 1,3-diaminopentane;

Specific examples of aromatic or aliphatic tetracarboxylic dianhydrides include pyromellitic anhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetra Carboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, bicyclo(2.2.2)oct-7-ene-2,3,5,6-tetracarboxylic dianhydride , diethylenetriaminepentaacetic dianhydride, ethylenediaminetetraacetic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride , 4,4′-oxydiphthalix anhydride, 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride, 2,2′-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 4,4'-bisphenol A diphthalic anhydride, 5-(2,5-dioxytetrahydro)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, ethylene glycol bis(trimellit acid anhydride), hydroquinone diphthalic anhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride anhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2 ,4,5-cyclohexanetetracarboxylic dianhydride, 1,1′-bicyclohexane-3,3′,4,4′-tetracarboxylic acid-3,4:3′,4′-dianhydride, 4 -(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride, 5-(2,5-dioxotetrahydrofuryl)-3- methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 2,3,4 ,5-tetrahydrofurantetracarboxylic acid dianhydride, 3,5,6-tricarboxy-2-norbornane acetic acid dianhydride, and particularly pyromellitic anhydride and 1,2,4,5-cyclohexanetetracarboxylic acid. Dianhydrides are preferred. A specific product name is BMI-3000 manufactured by Designers Molecules Inc.

A terminal-modified polyimide resin which is a reaction product of an aliphatic diamine and an aliphatic or aromatic acid dianhydride in the resin composition of the present invention and which is a reaction product of a polyimide resin having amino groups at both ends and maleic anhydride. is usually 3 to 50 parts by mass, preferably 5 to 40 parts by mass, per 100 parts by mass of the polymer compound represented by formula (1). Content of a terminal-modified polyimide resin that is a reaction product of an aliphatic diamine and an aliphatic or aromatic acid dianhydride with respect to a polymer compound and that is a reaction product of a polyimide resin having amino groups at both ends and maleic anhydride is within the above range, various excellent properties of the cured product of the resin composition of the present invention are exhibited.

An organic solvent may be used in combination with the resin composition of the present invention. Specific examples of organic solvents include aromatic solvents such as toluene and xylene; solvents, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone and cyclohexanone, lactones such as γ-butyrolactone and γ-valerolactone, N-methylpyrrolidone (NMP), N,N-dimethylformamide (DMF), Amide solvents such as N,N-dimethylacetamide and N,N-dimethylimidazolidinone, sulfones such as tetramethylenesulfone, and the like. The content of the organic solvent in the resin composition of the present invention is usually 90% by mass or less, preferably 30 to 80% by mass.

A polymerization inhibitor may be used in combination with the resin composition of the present invention in order to improve storage stability. The polymerization inhibitor that can be used in combination is not particularly limited as long as it is generally known, and examples thereof include quinones such as hydroquinone, methylhydroquinone, p-benzoquinone, chloranil and trimethylquinone, aromatic diols, and di-t-butyl. Hydroxytoluene and the like can be mentioned.

The resin composition of the present invention can be used by blending fillers and additives in an amount within a range that does not impair the original performance for the purpose of imparting desired performance according to its use. The filler may be fibrous or powdery, and includes silica, carbon black, alumina, talc, mica, glass beads, glass hollow spheres, and the like.

The resin composition of the present invention can also be used in combination with flame retardant compounds, additives, and the like. These are not particularly limited as long as they are commonly used. For example, flame-retardant compounds include bromine compounds such as 4,4-dibromobiphenyl, phosphate esters, melamine phosphate, phosphorus-containing epoxy resins, nitrogen compounds such as melamine and benzoguanamine, oxazine ring-containing compounds, and silicon compounds. are mentioned. Additives include ultraviolet absorbers, antioxidants, photopolymerization initiators, fluorescent brighteners, photosensitizers, dyes, pigments, thickeners, lubricants, antifoaming agents, dispersants, leveling agents, and brighteners. etc., it is also possible to use them in combination as desired.

The resin composition of the present invention can be used by coating or impregnating various substrates. For example, when a thermal radical initiator is used, it can be applied as an interlayer insulating layer of a multilayer printed circuit board by applying it on a PET film, as a coverlay by applying it on a polyimide film, or as a resin by applying it on a copper foil and drying it. It can be used as an attached copper foil. Further, by impregnating glass cloth, glass paper, carbon fiber, various non-woven fabrics, etc., it can be used as a printed wiring board or CFRP prepreg. Furthermore, it can be used as various resists by using a photoradical initiator.

The interlayer insulating layer, coverlay, resin-coated copper foil, prepreg, and the like of the present invention can be cured under heat and pressure using a hot press or the like.

EXAMPLES The present invention will now be described in more detail with reference to examples and comparative examples. However, the present invention is not limited to these examples.

Synthesis Example 1 (synthesis of polymer compound used in the present invention)
(Step 1) Synthesis of a copolymer represented by the following formula (5) (copolymer 1): 38.5 parts of styrene and hydroquinone are added to a flask equipped with a thermometer, a cooling tube, a nitrogen gas inlet tube, and a stirrer. 1.5 parts of monomethacrylate, 0.4 parts of benzoyl peroxide and 10 parts of propylene glycol monomethyl ether acetate (PGMEA) are added and reacted at 120 to 130° C. for 5 hours in a nitrogen atmosphere to give a reaction represented by the following formula (5). A PGMEA solution of copolymer 1 was obtained. Part of the PEGMEA solution was heated under reduced pressure to remove the solvent and unreacted styrene, and the dry mass was calculated as the solid content. 8 parts, the resulting copolymer was a copolymer of 32.7 parts of styrene and 1.5 parts of hydroquinone monomethacrylate. The number average molecular weight of the sample subjected to the dry mass measurement was 38,000, and the weight average molecular weight was 161,000. From the copolymerization ratio of styrene and hydroquinone monomethacrylate and the number average molecular weight, the value of n in formula (5) is calculated to be 361 and the value of m is 9.

(Step 2) Synthesis of a polymer compound (polymer compound 1) of the present invention represented by the following formula (6) From the PGMEA solution of copolymer 1 obtained in step 1, unreacted styrene is heated under reduced pressure. After distilling off PGMEA together with PGMEA, PGMEA was added to obtain 138 parts of a 25% by mass solution of copolymer 1. 5 parts of triethylamine was added to this solution, and a part of methacrylic acid chloride was added and reacted at 60° C. with stirring for 1 hour. The reaction solution was pressure-filtered through a filter paper having a supplemental particle size of 1 micron to remove triethylamine hydrochloride, and excess triethylamine and PGMEA were distilled off from the filtrate using a rotary evaporator. 139 parts of a solution containing 25% by mass of the polymer compound represented by formula (6) (polymer compound 1) was obtained. The obtained polymer compound 1 had a number average molecular weight of 40,000 and a weight average molecular weight of 164,000.

Example 1 (Preparation of the resin composition of the present invention)
To 10 parts of the PGMEA solution of the polymer compound 1 obtained in Synthesis Example 1, 0.05 parts of dicumyl peroxide as a radical initiator and a maleimide resin represented by the following formula (7) (manufactured by Designer Molecules Inc. The resin composition 1 of the present invention was obtained by adding 0.5 part of product name BMI-3000J) and mixing uniformly.

Comparative Example 1 (Preparation of resin composition for comparison)
Resin composition 2 for comparison was obtained by adding 0.05 part of dicumyl peroxide as a radical initiator to 10 parts of the PGMEA solution of polymer compound 1 obtained in Synthesis Example 1 and uniformly mixing them.

(Evaluation of dielectric properties of cured product of resin composition)
The resin compositions 1 and 2 obtained in Example 1 and Comparative Example 1 were applied to a mirror surface of a copper foil having a thickness of 18 μm using an applicator to a thickness of 280 μm, respectively, and heated at 90° C. for 10 minutes to dissolve the solvent. was dried. The film-like adhesive on the copper foil obtained above was cured by heating at 180° C. for 1 hour using a vacuum oven, and then the copper foil was removed by immersion in an etchant. From the film adhesive composed of the resin composition 1 of the present invention and the comparative resin composition 2, a cured product with a thickness of 70 μm that can be handled as a film was obtained. Dielectric properties were evaluated. The dielectric properties were evaluated by measuring the dielectric constant and dielectric loss tangent at 10 GHz by the cavity resonance method using a network analyzer 8719ET (manufactured by Agilent Technologies). Also, the glass transition temperature and α1 (linear expansion coefficient in the glassy region) were measured using a TMA (thermo-mechanical property apparatus). Table 1 shows the results.

(Evaluation of Adhesion Strength of Cured Product of Resin Composition)
The resin compositions 1 and 2 obtained in Example 1 and Comparative Example 1 were applied to a high-frequency low-roughness copper foil (CF-T4X-SV: manufactured by Fukuda Metal Foil & Powder Co., Ltd.) with a thickness of 12 μm using an applicator. A copper foil having a film-like adhesive made of the resin composition of the present invention was obtained by coating the matte surface with a thickness of 50 μm and drying the solvent by heating at 90° C. for 10 minutes. On the adhesive side of the copper foil obtained above, the matte side of the same copper foil as above was superimposed and cured by heating at a pressure of 3 MPa for 1 hour in a vacuum press, and then the copper foil was peeled off at 90°. Strength (adhesive strength) was measured using Autograph AGX-50 (manufactured by Shimadzu Corporation). Table 1 shows the results.

As described above, the cured product of the resin composition of the present invention formed a flexible film and exhibited high heat resistance and adhesiveness while maintaining excellent dielectric properties.

Claims (3)

Formula (1) below

(Wherein, R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group; m and n are the average number of repeating units and are each independently in the range of 1 to 2,000.) A polymer compound, a terminal-modified polyimide resin that is a reaction product of an aliphatic diamine and an aliphatic or aromatic acid dianhydride and is a reaction product of a polyimide resin having amino groups at both ends and maleic anhydride, and A resin composition containing a radical initiator. A film adhesive comprising the resin composition according to claim 1 . The cured product of the resin composition according to claim 1 or the film adhesive according to claim 2.