JP2000273303A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition excellent in heat resistance, low out-gas properties, and low-temperature processability and capable of giving a varnish not undergoing separation into two upper and lower layers by compounding a polyimide resin with a chain-extended epoxy resin having a specified or higher molecular weight, a silane coupling agent, and an epoxy-resin-grafted polyimide. SOLUTION: This composition essentially consists of 100 pts.wt. (A) polyimide resin, 1-100 pts.wt. (B) chain-extended epoxy resin having a molecular weight of 2,000 or above, 0.26-5.10 pts.wt. (C) silane coupling agent, and 0.3-54.0 pts.wt. (D) epoxy-resin-grafted polyimide. It is desirable that component B is synthesized from a difunctional epoxy resin and a difunctional phenolic compound, a difunctional carboxylic acid, or an amine having two active hydrogen atoms, and component D is one in which at least part of the main chain skeleton is synthesized from the same materials as used in component A, and at least part of the side chains grafted thereonto are synthesized from the same materials as used in component B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to heat resistance, adhesiveness,
The present invention relates to a resin composition which is excellent in low outgassing property and low-temperature processability and does not separate into two layers in a varnish state.

[0002]

2. Description of the Related Art Polyimide resin has high heat resistance, flame retardancy, and excellent electrical insulation. Therefore, it is used as a film for flexible printed wiring boards and substrates for heat resistant adhesive tapes, and as a resin varnish for semiconductors. Widely used for interlayer insulating films and surface protection films. In recent years, adhesives having excellent heat resistance, adhesiveness, low outgassing properties, and low-temperature processability for bonding these polyimide films have been required, and thermoplastic polyimide resins and flexible high molecular weight epoxies have been required. A resin hybrid adhesive has been devised (Japanese Patent Application No. 9-357222).

[0003]

However, in the varnishes of these resin compositions, since the compatibility between the polyimide resin and the high molecular weight epoxy resin is poor, the epoxy resin and the polyimide are separated into two layers during the storage period. It is necessary to stir and mix uniformly immediately before use. The present invention is excellent in heat resistance, adhesiveness, low outgassing properties, and low-temperature processability, and as a result of intensive research to obtain a resin in which epoxy resin and polyimide do not separate in a varnish state, polyimide resin and chain-extended epoxy resin It has been found that the above problems can be solved by adding an epoxy resin-grafted polyimide to the hybrid adhesive described above, and the present invention has been completed.

[0004]

That is, the present invention provides 100 parts by weight of a polyimide resin (A), 1 to 100 parts by weight of a chain-extended epoxy resin (B) having a molecular weight of 2,000 or more, and 0 parts by weight of a silane coupling agent (C). .26 to 5.10 parts by weight, and 0.3 to 54.0 parts by weight of the epoxy resin-grafted polyimide (D) as essential components.

In the production of the polyimide resin (A) and the epoxy resin-grafted polyimide (D) used in the present invention, diamines and tetracarboxylic anhydrides are used. Examples of the diamines include m-phenylenediamine and p-diamine. Phenylenediamine, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylmethane, benzidine, 4,4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 3,3 '
-Diaminodiphenylsulfone, 4,4'-diaminodiphenylether, 2,6-diaminopyridine, bis (4
-Aminophenyl) phosphine oxide, bis (4-aminophenyl) -N-methylamine, 1,5-diaminonaphthalene, 3,3′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dimethoxybenzidine, 2,4-bis (β-
Amino-t-butyl) toluene, bis (p-β-amino-
t-butylphenyl) ether, 1,3-bis (3-aminophenoxy) benzene, p-bis (2-methyl-4-aminobenzyl) benzene, p-bis (1,1-dimethyl-
5-aminopentyl) benzene, 2,8-diaminodiphenylene oxide, 2,4-diaminotoluene, diaminodulene, 4,4′-bis (m-aminophenoxy) diphenylsulfone, 4,4′-bis (m -Aminophenoxy) diphenyl ether, 4,4'-bis (p-aminophenoxy) diphenyl ether, 4,4'-bis (m-aminophenoxy) diphenylmethane, 4,4'-bis (p-aminophenoxy) diphenylmethane, m- Xylylenediamine, p-xylylenediamine, bis (p-aminocyclohexyl) methane, ethylenediamine, propylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, 3-methylheptamethylenediamine 4,4-dimethylhepta Ethylenediamine,
2,11-diaminodecane, 1,2-bis (3-aminopropoxy) ethane, 2,2-dimethylpropylenediamine, 3-methoxyhexamethylenediamine, 2,5-dimethylhexamethylenediamine, 2,5-dimethylnona Methylene diamine, 1,4-diaminocyclohexane,
2,12-diaminooctadecane, 2,5-diamino-
1,3,4-oxadiazole, 1,3-bis (3-aminopropyldimethyl) siloxane, 1,3-bis (3-aminophenyl) siloxane, 1,3-bis (3-aminopropyldimethylmethylsilyl) ) Benzene, 3,3'-dimethylbenzidine, 3,3'-bis (trifluoromethyl) benzidine, 4,4'-diaminoterphenyl, 4,4'-diaminoquaterphenyl and the like are used. These may be used alone or in combination of two or more.

On the other hand, tetracarboxylic anhydrides include:
Pyromellitic anhydride, 2,3,6,7-naphthalenetetracarboxylic anhydride, 3,3 ', 4,4'-biphenyltetracarboxylic anhydride, 1,2,5,6-naphthalenetetracarboxylic acid Anhydride, 2,2 ', 3,3'-biphenyltetracarboxylic anhydride, 2,2-bis (3,4-dicarboxydiphenyl) propanoic anhydride, 3,3', 4,4'-benzophenone Tetracarboxylic anhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic anhydride, 4,4-hexafluoroisopropylidenebis (phthalic anhydride), 3,4,
9,10-perylenetetracarboxylic anhydride, bis (3,
4-dicarboxydiphenyl) ether anhydride, ethylenetetracarboxylic anhydride, naphthalene-1,2,4,5
-Tetracarboxylic anhydride, naphthalene-1,4,5,8
-Tetracarboxylic anhydride, 4,8-dimethyl-1,2,
3,5,6,7-hexahydronaphthalene-1,2,5,6-
Tetracarboxylic anhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic anhydride, phenanthrene-1,2,9,10-tetracarboxylic anhydride, cyclopentane-1,2, 3,4-tetracarboxylic anhydride,
Pyrrolidine-2,3,5,6-tetracarboxylic anhydride,
Pyrazine-2,3,5,6-tetracarboxylic anhydride, 2,
2-bis (2,5-dicarboxyphenyl) propane anhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane anhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane anhydride Anhydride, bis (2,3-dicarboxyphenyl) methane anhydride, bis (3,4-dicarboxyphenylsulfone anhydride, benzene-1,2,3,4-tetracarboxylic anhydride, 1,2,3 , 4-butanetetracarboxylic anhydride, 1,2,3,4-butanetetracarboxylic anhydride, thiophene-2,3,4,5-tetracarboxylic anhydride, etc., which may be used alone or Two or more kinds may be used in combination.

The reaction between the tetracarboxylic dianhydride and the diamine is carried out by a known method in an aprotic polar solvent. Examples of aprotic polar solvents include N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAC), and N-methyl-2-pyrrolidone (NM
P), tetrahydrofuran (THF), diglyme, cyclohexanone, 1,4-dioxane (1,4-DO) and the like can be used. One type of aprotic polar solvent may be used alone, or two or more types may be mixed and used.

Further, a non-polar solvent compatible with an aprotic polar solvent may be used as a mixture. For example, aromatic hydrocarbons such as toluene, xylene, and solvent naphtha can be used. The proportion of the non-polar solvent in the mixed solvent is preferably 30% by weight or less. This is because when the nonpolar solvent is 30% by weight or more, the solvent power of the solvent is reduced, and polyamic acid may be precipitated.
The reaction between the tetracarboxylic dianhydride and the diamine is carried out by dissolving the well-dried diamine component in the above-mentioned dehydrated and purified reaction solvent and adding thereto the ring-closing rate of 98%, more preferably 99% or more. The reaction is allowed to proceed by adding the anhydride.

The polyamic acid solution thus obtained is subsequently subjected to dehydration cyclization by heating in an organic solvent to obtain imidized polyimide. Water generated by the imidization reaction interferes with the ring closure reaction, so that an organic solvent that is incompatible with water is added to the system and azeotroped, and Dean-Stark (Dea Stark) is used.
Discharge out of the system using a device such as an n-Stark tube. Dichlorobenzene is known as an organic solvent that is incompatible with water, but the above-mentioned aromatic hydrocarbons are preferably used for electronics because a chlorine component may be mixed therein.

The use of compounds such as acetic anhydride, β-picoline and pyridine as catalysts for the imidation reaction is not hindered. The higher the imidization rate is, the better the imidization rate is.If the imidation rate is low, imidization occurs due to heat during use such as thermocompression bonding,
Since the generation of water is not preferable, it is desirable that an imidization ratio of 95% or more, more preferably 98% or more is achieved. The polyimide used preferably has a polysiloxane structure in the main chain. This is because they are excellent in low water absorption and can be bonded in a short time at a low temperature.

Next, the chain-extended epoxy resin (B) used in the present invention comprises a bifunctional epoxy resin and a bifunctional phenol compound, a bifunctional carboxylic acid or active hydrogen.
The phenol compound is synthesized from an amine having two phenol compounds. As a phenol compound used as a raw material, a bifunctional phenol compound such as bisphenol A, bisphenol F, and biphenol can be used alone or in combination of two or more. Further, as the carboxylic acid, phthalic acid, tetrahydrophthalic acid, cyclohexanedicarboxylic acid, succinic acid,
Dicarboxylic acids such as fumaric acid can be used alone or in combination of two or more. As the amine, primary amines having two active hydrogens such as hexylamine and aniline, and secondary amines having two active hydrogens such as piperazine can be used alone or in combination of two or more. .

However, as materials for electronics,
It is preferable to use a phenol compound among these, since those having a low water absorption are good. In particular, bisphenol A is preferably used in order to obtain a chain-extended epoxy resin having a good balance between high heat resistance and flexibility.

On the other hand, epoxy resins such as ethylene glycol type, bisphenol A type, bisphenol F
Type, biphenol type or other bifunctional epoxy resin is used alone or in combination of two or more. In order to obtain a chain-extended epoxy resin having excellent flexibility, it is preferable to use oligoethylene glycol diglycidyl ether as a raw material. One example of the structure of the epoxy resin synthesized from bisphenol A and oligoethylene glycol diglycidyl ether is shown in Structural formula [1]. When the number of repeating n of oligoethylene glycol diglycidyl ether is 1, the chain is The flexibility of extended epoxy resins is relatively low. Further, when n is 8 or more, the flexibility becomes too high, and there is a problem that the resin flows too much during thermocompression bonding. Therefore, n is 2
It is better to be at least 8 and less than 8.

[0014]

Embedded image

The chain-extended epoxy resin (B) preferably has a molecular weight of 2,000 or more. In this case, the number m of repetitions in the structural formula [1] is preferably 3 or more. If the molecular weight is less than 2,000, the epoxy resin volatilizes or decomposes due to heating during thermocompression bonding to generate gas.

In the production of the epoxy resin-grafted polyimide (D) of the present invention, bisphenol A type, bisphenol F type, bisphenol S type, biphenol type, naphthalene type, novolak type, ziloc type, siloxane skeleton-containing type, etc. Epoxy resin is used. These commercially available products can be used alone or in combination of two or more. In addition, a commercially available polyfunctional epoxy resin is reacted with a monofunctional phenol compound, a monofunctional carboxylic acid compound, an amine compound having one active hydrogen to obtain a monofunctional epoxy resin or a commercially available bifunctional epoxy resin with diphenol. A high-molecular-weight epoxy resin obtained by previously reacting with a compound, a dicarboxylic acid compound, an amine compound having two active hydrogens, or the like, or one obtained by end-capping it at one end can also be used.

Epoxy resin grafted polyimide (D)
First, a polyamic acid is synthesized. In the synthesis of the polyamic acid, the reaction between the tetracarboxylic dianhydride and the diamine is performed by a known method in an aprotic polar solvent. As the aprotic polar solvent, N,
N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAC), N-methyl-2-pyrrolidone (NMP), tetrahydrofuran (THF), diglyme, cyclohexanone, 1,4-dioxane (1,4
-DO) can be used. The aprotic polar solvent is
One type may be used alone, or two or more types may be mixed and used.

At this time, a non-polar solvent compatible with the aprotic polar solvent may be mixed and used. For example, aromatic hydrocarbons such as toluene, xylene, and solvent naphtha are used. The proportion of the non-polar solvent in the mixed solvent is preferably 30% by weight or less. This is because if the nonpolar solvent is 30% by weight or more, the solvent's dissolving power is reduced, and polyamic acid may be precipitated. The reaction between the tetracarboxylic dianhydride and the diamine is
The well-dried diamine component is dissolved in the dehydrated and purified reaction solvent, and the ring closure ratio is 98%, more preferably 99%.
The above-mentioned well-dried tetracarboxylic dianhydride is added to proceed the reaction.

The polyamic acid is synthesized by a known method, and the resulting polyamic acid is partially polyimideated so as to have a target grafting ratio. The imidation rate is determined by the amount of dewatered matter trapped in the Dean-Stark tube.

Next, an epoxy resin is added and reacted with the carboxyl group of the partially imidized polyamic acid. The main chain of the polyimide / epoxy resin graft copolymer is synthesized using at least a part of the same raw material as the raw material of the polyimide to be made compatible with the epoxy resin. In particular, it is preferable that the same raw material and the same mixing ratio are used as the polyimide to be made compatible with the epoxy resin. Further, the epoxy resin side chain grafted on the polyimide skeleton is synthesized using at least a part of the same raw material as the raw material of the epoxy resin to be made compatible with the polyimide. In particular, it is preferable to use the same raw material and the same mixing ratio as the epoxy resin to be made compatible with the polyimide.

The mixing ratio of the chain-extended epoxy resin (B) is 1 to 100 parts by weight of the polyimide resin (A).
It is preferably in the range of 100 parts by weight, especially 20 to 50 parts by weight. If the amount is less than 1 part by weight, the effect of improving the peel strength is difficult to appear, and if it exceeds 100 parts by weight, the heat resistance of the resin is impaired, which is not preferable. The mixing ratio of the epoxy resin-grafted polyimide (D) is from 0.3 to 54.0.
Parts by weight. This is because if the amount is less than 0.3 parts by weight, the compatibility between the polyimide and the epoxy resin is not improved.
If it exceeds 54.0 parts by weight, the epoxy resin-grafted polyimide (D) also forms a continuous phase, which impairs the heat resistance of the polyimide resin (A), which is not preferred.

A silane coupling agent (C) is added as an auxiliary agent for improving the adhesion to the adherend. The mixing ratio is 0.26 with respect to 100 parts by weight of the polyimide resin (A). -5.10 parts by weight, which means that an epoxy group and a chemical equivalent of active hydrogen of amine were blended.

The resin composition obtained by adding the chain-extended epoxy resin, the epoxy resin-grafted polyimide, and the silane coupling agent to the polyimide resin of the present invention can be used in a varnished state without separating the polyimide and the epoxy resin into two upper and lower layers. No varnish stirring just before use is required, and an adhesive having stable properties can be supplied. Also, by evaporating the solvent, the polyimide resin and the epoxy resin undergo phase separation, and the polyimide forms a continuous phase and the epoxy resin forms a discontinuous phase, so the apparent glass transition temperature is the same as the glass transition temperature of the polyimide. It is about the same and maintains high heat resistance.

On the other hand, the low-temperature processability is improved over the original polyimide by adding a chain-extended epoxy resin having excellent flexibility, and no peeling is observed even when subjected to thermal shock such as IR reflow. Physical properties are improved. As described above, a resin composition having excellent heat resistance, adhesiveness, and low outgassing properties can be obtained.

[0025]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited thereto.

[Synthesis of Polyimide] In a four-necked flask equipped with a dry nitrogen gas inlet tube, a cooler, a thermometer, and a stirrer,
Add 186.63 g of dehydrated and purified NMP and stir vigorously for 10 minutes while flowing nitrogen gas. Next, 2,2-
116.23 g of bis (4- (4-aminophenoxy) phenyl) propane (BAPP), 55.54 g of 1,3-bis (3-aminophenoxy) benzene (APB), α, ω-bis (837 having an average molecular weight of 837) 218.25 g of 3-aminopropyl) polydimethylsiloxane (APPS) and 2.78 g of APPS having an average molecular weight of 249 were added, and the system was charged to 60%.
Heat to ° C and stir until uniform.

After homogeneously dissolving, the system was cooled to 5 ° C. in an ice water bath, 153.46 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA), benzophenone tetracarboxylic dianhydride (BTDA) 72.03 g,
The addition was continued over 15 minutes while keeping the powdery state, and then stirring was continued for 3 hours. During this time, the flask was kept at 5 ° C.

After that, remove the nitrogen gas inlet pipe and the cooler,
A Dean-Stark tube filled with toluene was attached to the flask, and 229.66 g of toluene was added to the system. The system was heated to 175 ° C. in place of the oil bath, and the generated water was removed from the system. After heating for 4 hours, no water was generated from the system. After cooling, the reaction solution was poured into a large amount of methanol to precipitate a polyimide resin. After the solid content was filtered, the residue was dried under reduced pressure at 80 ° C. for 12 hours to remove the solvent and obtain 569.53 g (yield 92.1%) of a solid resin. When the infrared absorption spectrum was measured by the KBr tablet method, an absorption of 5.6 μm derived from the cyclic imide bond was recognized, but an absorption of 6.06 μm derived from the amide bond was not observed. It was confirmed that the imidization was 100%.

[Synthesis of chain-extended epoxy resin] In a flask equipped with a thermometer and a stirrer, 100.00 g of diethylene glycol diglycidyl ether (Denacol EX850, manufactured by Nagase Kasei Kogyo Co., Ltd.) and bisphenol A (Wako Pure Chemical Industries, Ltd.) 100.15 g) and stirred at 80 ° C. until uniform. Thereafter, 1.00 g of triphenylphosphine (manufactured by Wako Pure Chemical Industries, Ltd.) is added to the mixed solution, and the mixture is stirred at 80 ° C. until uniform. Thereafter, stirring was continued at 80 ° C. for 2 hours, transferred to an aluminum container, and then reacted at 150 ° C. for 3 hours.

[Synthesis of Epoxy Resin Grafted Polyimide] (Example 1) Dehydrated and purified NMP10 was placed in a four-necked flask equipped with a dry nitrogen gas inlet tube, a cooler, a thermometer, and a stirrer.
Add 5.00 g and stir vigorously for 10 minutes while flowing nitrogen gas. Next, diaminophenylbenzene (AP
B) 5.00 g, 10.45 g of 2,2-bis (4- (4-aminophenoxy) phenyl) propane (BAPP), α, ω-bis (3-aminopropyl) polydimethylsiloxane having an average molecular weight of 837 ( (APPS) 19.62 g, 0.25 g of APPS having an average molecular weight of 249 was added, and
Heat to 0 ° C. and stir until uniform.

After homogeneously dissolving, the system was cooled to 5 ° C. in an ice-water bath and benzophenonetetracarboxylic dianhydride (BT)
6.48 g of DA) and 13.80 g of biphenoltetracarboxylic dianhydride (BPDA) were added in the form of powder over 15 minutes, and then stirring was continued for 3 hours. During this time, the flask was kept at 5 ° C. Next, the nitrogen gas inlet tube and the condenser were removed, a Dean-Stark tube filled with toluene was attached to the flask, and 26.25 g of toluene was added to the system. The system was heated to 175 ° C. in place of the oil bath, and the generated water was removed from the system. After heating for 2 hours, the amount of water generated from the system was 0.97 g.

The reaction solution was mixed with ethylene glycol diglycidyl ether and bisphenol A,
Bifunctional high molecular weight epoxy resin (weight average molecular weight of 4,000
268.30 g) was added and stirred to dissolve. Thereafter, 2.68 g of triphenylphosphine was added and reacted at 150 ° C. for 3 hours. After cooling, this reaction solution was poured into a large amount of acetone to precipitate an epoxy resin-grafted polyimide. The solid was filtered and washed with acetone. Wash the solid at 80 ° C
For 2 hours under reduced pressure to remove the solvent. When the infrared absorption spectrum was measured by the KBr tablet method, no absorption at 1,710 cm ^-1 derived from the carboxyl group could be recognized, and an absorption at 1,730 cm ^-1 derived from the ester bond was recognized. It was confirmed that the compound was obtained by grafting an epoxy resin to polyimide. The obtained epoxy resin-grafted polyimide was N-methylpyrrolidone (NM
P), dimethylformamide (DMF), and 1,4-dioxane (1,4-DO).

To 100 parts by weight of the polyimide obtained above and 10 parts by weight of the chain-extended epoxy resin, 0.30 parts by weight of the epoxy resin-grafted polyimide of this example and 0.26 parts by weight of a silane coupling agent were added. Then, the resultant was dissolved in NMP to prepare a varnish having a resin content of 35%. The compatibility of the varnish was visually observed, and the results are shown in Table 1.

Example 2 APB, BAPP, and A
PPS, BTDA and BPDA were reacted in the same manner as in Example 1, heated for 1 hour and 15 minutes, and when the water generated from the system reached 0.60 g,
Bisphenol A type epoxy resin (Epicoat 828,
60.37 g of Yuka Shell Epoxy Co., Ltd.)
Stir and dissolve. Thereafter, 0.60 g of triphenylphosphine was added and reacted at 150 ° C. for 3 hours. After cooling, the same treatment as in Example 1 was performed to obtain a dried epoxy resin-grafted polyimide.

In the same manner as in Example 1, a compound obtained by grafting an epoxy resin to polyimide was used.
It was confirmed that it was well dissolved in P, DMF, and 1,4-DO. Furthermore, a varnish with a resin content of 35% was prepared,
The compatibility of the varnish was visually observed. The results are shown in Table 1.

Example 3 APB, BAPP, and A
PPS, BTDA and BPDA were reacted in the same manner as in Example 1, heated for 1 hour and 15 minutes, and when the water generated from the system reached 0.60 g,
Bisphenol A type epoxy resin (Epicoat 100
4, 241.48 g of Yuka Shell Epoxy Co., Ltd.) was added and stirred to dissolve. Thereafter, 2.41 g of triphenylphosphine was added and reacted at 150 ° C. for 3 hours. After cooling, the same treatment as in Example 1 was performed to obtain a dried epoxy resin-grafted polyimide.

In the same manner as in Example 1, a compound obtained by grafting an epoxy resin to polyimide was used.
It was confirmed that it was well dissolved in P, DMF, and 1,4-DO. Furthermore, a varnish with a resin content of 35% was prepared,
The compatibility of the varnish was visually observed. The results are shown in Table 1.

(Example 4) Polyimide 1 obtained above
5 parts by weight of the epoxy resin-grafted polyimide obtained in Example 1 were added to 00 parts by weight and 10 parts by weight of the chain-extended epoxy resin.
4.0 parts by weight and 0.26 parts by weight of a silane coupling agent were added and dissolved in NMP to prepare a varnish having a resin content of 35%. The compatibility of the varnish was visually observed, and the results are shown in Table 1.

(Comparative Example 1) Polyimide 1 obtained above
The epoxy resin-grafted polyimide obtained in Example 1 was added in an amount of 0.1 part by weight to 00 parts by weight and 10 parts by weight of the chain-extended epoxy resin.
25 parts by weight and 0.26 parts by weight of a silane coupling agent were added and dissolved in NMP to prepare a varnish having a resin content of 35%. The compatibility of the varnish was visually observed, and the results are shown in Table 1.

(Comparative Example 2) Polyimide 1 obtained above
To 100 parts by weight and 10 parts by weight of the chain-extended epoxy resin, the epoxy resin-grafted polyimide obtained in Example 2 was added in an amount of 0.1%.
25 parts by weight and 0.26 parts by weight of a silane coupling agent were added and dissolved in NMP to prepare a varnish having a resin content of 35%. The compatibility of the varnish was visually observed, and the results are shown in Table 1.

Comparative Example 3 Polyimide 1 Obtained Above
To 100 parts by weight and 10 parts by weight of the chain-extended epoxy resin, the epoxy resin-grafted polyimide obtained in Example 3 was added in an amount of 0.1 part.
25 parts by weight and 0.26 parts by weight of a silane coupling agent were added and dissolved in NMP to prepare a varnish having a resin content of 35%. The compatibility of the varnish was visually observed, and the results are shown in Table 1.

(Comparative Example 4) Polyimide 1 obtained above
5 parts by weight of the epoxy resin-grafted polyimide obtained in Example 1
5.0 parts by weight and 0.26 parts by weight of a silane coupling agent were added and dissolved in NMP to prepare a varnish having a resin content of 35%. The compatibility of the varnish was visually observed, and the results are shown in Table 1.

(Comparative Example 5) Polyimide 1 obtained above
To 00 parts by weight and 10 parts by weight of the chain-extended epoxy resin, 0.26 parts by weight of a silane coupling agent was added and dissolved in NMP to prepare a varnish having a resin content of 35%. The compatibility of the varnish was visually observed, and the results are shown in Table 1.

[Preparation and Evaluation of Film] Examples 1-4
And casting the varnish prepared in Comparative Examples 1 to 5,
By drying at 0 ° C. for 10 minutes, at 150 ° C. for 10 minutes, and at 180 ° C. for 10 minutes, a film having a thickness of 30 μm was obtained. Using this film, a dynamic viscoelasticity measuring device (DMS21
0, manufactured by Seiko Denshi Kogyo Co., Ltd.). The glass transition temperature was determined from the tan δ peak of the cured resin composition, and the heat resistance was evaluated. The result is
The results are shown in Table 1.

[0045]

[Table 1]

As is apparent from the results, the compatibility between the polyimide and the epoxy resin is improved by adding 0.3 parts by weight or more of the epoxy resin-grafted polyimide having a similar structure to the polyimide and the epoxy resin to be made compatible. We were able to. However, when 55.0 parts by weight or more of the epoxy resin-grafted polyimide was added, the glass transition temperature of the resin composition was lowered. This means that the heat resistance of the resin composition has decreased.

[0047]

According to the present invention, it is possible to provide a highly reliable adhesive which is excellent in heat resistance, adhesiveness, low outgassing, low temperature processability, and does not cause phase separation in a varnish state. is there. By mixing a polyimide with a chain-extended epoxy resin, an epoxy resin-grafted polyimide, and a silane coupling agent, low-temperature processability and peel strength can be increased while maintaining the heat resistance of the polyimide. In addition, since the polyimide and the epoxy resin do not separate into the upper and lower layers in the varnish state, the stirring operation immediately before use becomes unnecessary, and a stable film adhesive can be supplied. For this reason, it is extremely useful industrially as a material for electronics requiring high reliability and heat resistance.

Continued on the front page F-term (reference) 4J002 CD20X CM04W CM04Y EX036 EX076 FB26Y GQ00 GQ05 4J036 AA01 AA04 AB10 AD01 CA08 CA19 CB04 JA07 JA08 4J043 PA11 QB31 RA06 RA35 SA06 SA31 SA42 SA61 SA81 SB02 TA22 TA31 TA74 UA 121 UA UA 129 UB022 UB052 UB121 UB122 UB281 UB301 UB351 VA011 VA021 VA022 VA051 VA062 VA102 XA16 XA19 YB29 ZA02 ZA12 ZB50

Claims (4)

[Claims] 1. A chain-extended epoxy resin (B) having 100 parts by weight of a polyimide resin (A) and a molecular weight of 2,000 or more.
00 parts by weight, silane coupling agent (C) 0.26 to 5.
A resin composition comprising 10 parts by weight and 0.3 to 54.0 parts by weight of an epoxy resin-grafted polyimide (D) as essential components. 2. The chain-extended epoxy resin (B) is synthesized from a bifunctional epoxy resin and a bifunctional phenol compound, a bifunctional carboxylic acid, or an amine having two active hydrogens. The resin composition according to claim 1, wherein 3. The resin composition according to claim 1, wherein the chain-extended epoxy resin (B) is obtained by reacting oligoethylene glycol diglycidyl ether with bisphenol A. 4. An epoxy resin-grafted polyimide (D) having at least a part of a main chain skeleton synthesized using the same raw material as the polyimide resin (A), and at least a part of a side chain grafted thereto is a chain. The resin composition according to claim 1, wherein the resin composition is synthesized using the same raw material as the extended epoxy resin (B).