JP2002060620A - Polyimide solution excellent in storage stability, polyimide-based adhesive solution and film-like laminated member obtained using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyimide solution excellent in storage stability useful in the fields such as flexible printed circuit boards, tapes for TAB(tape automated bonding), composite lead frames, laminated materials and the like, where heat resistance and adhesion properties are required, a polyimide-based adhesive solution excellent in heat resistance and adhesion properties, and a film-like laminated member obtained using the same. SOLUTION: The polyimide solution having storage stability excellent enough to be stored for at least one month at room temperature is obtained by controlling imidization ratio to at least 90% in the soluble thermoplastic polyimide resin solution. Likewise, in the polyimide-based adhesive solution obtained by compounding a thermosetting resin and a curing agent, a high adhesive force can be maintained after a long-term storage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyimide solution,
The present invention relates to a polyimide-based adhesive solution and a film-like laminated member obtained using the same. More specifically, a flexible printed circuit board, TAB (Tape Automate)
d bonding) tape, composite lead frame,
A polyimide solution with good storage stability, a polyimide adhesive having excellent heat resistance and adhesiveness, and a film-like laminated member obtained by using the same, which is useful in fields requiring heat resistance and adhesiveness of laminated materials and the like. .

[0002]

2. Description of the Related Art In recent years, electronic devices have become more sophisticated and more sophisticated.
With miniaturization progressing, there has been a demand for miniaturization and weight reduction of electronic components used accordingly. For this reason, a semiconductor element packaging method and a wiring material or a wiring component for mounting the same are required to have higher density, higher function and higher performance. In particular, semiconductor packages, COL and LOC packages, MCM (M
There is a need for a material exhibiting good adhesiveness that can be suitably used as a high-density packaging material such as multi chip module, a printed wiring board material such as a multilayer FPC, and an aerospace material.

[0003] In this field, polyimide adhesives have been gradually used as adhesives having flexibility not found in phenolic and epoxy adhesives and heat resistance not found in acrylic adhesives.

Polyimide is excellent in heat resistance among various organic polymers, and is therefore widely used in the fields of space and aviation, and is also used as an adhesive material. But,
Polyimide adhesive with high heat resistance requires 30
A high temperature of about 0 ° C. and a high pressure are required, and the adhesive strength is not so high. Therefore, a thermosetting resin such as an epoxy resin is blended with a thermoplastic polyimide soluble in an organic solvent,
Adhesives with improved adhesion are emerging. However, when producing a thermoplastic polyimide, if imidization is not enough, the presence of polyamic acid, which is a precursor of the polyimide, causes a decrease in the molecular weight of the polyimide over time, depending on the storage state, or an adhesive. After blending, a reaction with the thermosetting resin to be blended may occur, which may cause deterioration in properties such as a decrease in adhesive strength and embrittlement of the adhesive.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present inventors
Solution to the above problems, polyimide solution with good storage stability,
The present inventors have conducted intensive studies with the aim of providing a polyimide-based adhesive solution using the same and a film-like laminated member obtained using the adhesive solution, and as a result, the present invention has been completed.

[0006]

SUMMARY OF THE INVENTION The present invention provides a novel polyimide solution having the following constitution, a polyimide-based adhesive solution using the same, and an adhesive solution thereof, thereby achieving the above object. Is done. 1) The imidation ratio is 90% or more, and the solubility at 20 # C in at least one solvent selected from tetrahydrofuran, 1,4-dioxane, dioxolan, N, N-dimethylformamide, and N, N-dimethylacetamide. A thermoplastic polyimide solution in which 10% or more of a thermoplastic polyimide is dissolved in an organic solvent,
A thermoplastic polyimide solution characterized in that the decrease in molecular weight after leaving it for one month in a 0 # C, 60% RH environment is 30% or less. 2) The thermoplastic polyimide is a polyimide made from an acid dianhydride, and 50 mol% or more of the total acid dianhydride is represented by the general formula (1)

[0007]

Embedded image

Wherein X represents-(CH ₂ ) k-or a divalent group containing an aromatic ring, and k is an integer of 1 or more and 10 or less. The thermoplastic polyimide solution according to 1), wherein: 3) A thermoplastic polyimide is obtained by combining an ester dianhydride represented by the general formula (1) with the following general formula (2)

[0009]

Embedded image

Wherein Y is the same or different and
(= O) -, - SO 2 -, - O -, - S -, - (CH 2)
_{m -, - NHCO -, -} C (CH 3) 2 -, - C (CF 3)
_A bond is shown to at least one selected from _2- , -C (= O) O- and a single bond. m and n are integers of 1 or more and 5 or less. The thermoplastic polyimide solution according to 1) or 2), which is a polyimide obtained using the diamine compound represented by (1) as a raw material. 4) The thermoplastic polyimide is represented by the following formula (3)

[0011]

Embedded image

The polyimide solution according to 3), which is a polyimide obtained by using the ester dianhydride represented by the formula and a diamine compound represented by the formula (2) as raw materials. 5) A polyimide adhesive solution obtained by mixing a thermosetting resin and a curing agent with the polyimide solution according to 1) to 4). 6) The polyimide adhesive solution according to 5), wherein the thermosetting resin is an epoxy resin. 7) The polyimide-based adhesive solution according to 5) or 6), wherein the decrease in molecular weight after leaving at room temperature for one month is 30% or less. 8) A film obtained by casting or coating the polyimide adhesive solution according to any one of 5) to 7) on a support, and peeling the dried adhesive coating film from the support. Laminated members. 9) The polyimide adhesive solution according to 5) to 7),
A film-shaped laminated member having on its surface a polyimide-based adhesive layer obtained by casting or coating on at least one surface of a polyimide film and then drying. 10) The film-shaped laminated member according to 9), wherein the polyimide-based adhesive layer has a thickness of 5 to 30 μm.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The thermoplastic polyimide solution of the present invention is a thermoplastic polyimide solution in which a thermoplastic polyimide having an imidization ratio of at least 90% and a solubility in an organic solvent of at least% is dissolved in the organic solvent. It is essential that the thermoplastic polyimide solution has a decrease in molecular weight of 30% or less after standing at room temperature for one month. Since this thermoplastic polyimide solution has little residual polyamic acid and does not cause a decrease in molecular weight or a reaction with other compounds even after long-term storage, for example, a thermosetting resin such as an epoxy resin is added to this solution. When a polyimide-based adhesive or a laminated member obtained by the above method is used, it has excellent stability without deteriorating adhesive properties such as a decrease in adhesive strength.

As the solvent used in the thermoplastic polyimide solution of the present invention and the polyimide adhesive solution obtained therefrom, from the viewpoint of processability when used as an adhesive, tetrahydrofuran (THF), 1,4-dioxane, A cyclic ether solvent such as dioxolane can be preferably used. When a mixed organic solvent obtained by mixing a plurality of solvents is used, it is preferable to combine the solvent with a polar organic solvent. However, it is desirable that the solvent contains 30% by weight or more, preferably 50% by weight or more of a cyclic ether solvent. The organic polar solvent used in combination with the cyclic ether-based solvent includes sulfoxide-based solvents such as dimethyl sulfoxide and diethyl sulfoxide, N, N-dimethylformamide, N, N-
Formamide solvents such as diethylformamide, N, N
-Acetamide solvents such as -dimethylacetamide and N, N-diethylacetamide.

From the viewpoint of good solubility in these solvents, the thermoplastic polyimide of the present invention is a thermoplastic polyimide obtained from an acid dianhydride as a raw material. (1)

[0016]

Embedded image

(Wherein, X represents-(CH ₂ ) k-or a divalent group containing an aromatic ring, and k is an integer of 1 or more and 10 or less). It is preferred that

Preferred examples of the acid dianhydride represented by the general formula (1) include 2,2-bis (4-hydroxyphenyl) propanedibenzoate-3,3 ', 4,4'-tetracarboxylic acid Dianhydride, p-phenylene bis (trimellitic acid monoester anhydride), 4,4′-biphenylene bis (trimellitic acid monoester anhydride), 1,4
-Naphthalene bis (trimellitic acid monoester anhydride), 1,2-ethylene bis (trimellitic acid monoester anhydride), 1,3-trimethylene bis (trimellitic acid monoester anhydride), 1,4- Examples include tetramethylene bis (trimellitic acid monoester anhydride), 1,5-pentamethylene bis (trimellitic acid monoester anhydride), 1,6-hexamethylene bis (trimellitic acid monoester anhydride), and the like. However, from the viewpoint that the obtained polyimide has good solubility and good balance with heat resistance, the formula (3) is used.

[0019]

Embedded image

2,2-bis (4-hydroxyphenyl) propanedibenzoate-3,3 ', 4
4'-tetracarboxylic dianhydride is particularly preferred.

The diamine component to be reacted with the above acid dianhydride is represented by the following general formula (2):

[0022]

Embedded image

(Wherein Y is the same or different and
(= O) -, - SO 2 -, - O -, - S -, - (CH 2)
_{m -, - NHCO -, -} C (CH 3) 2 -, - C (CF 3)
_It represents at least one kind of bond selected from _2- , -C (= O) O- or a single bond. m and n are integers of 1 or more and 5 or less. ), Particularly, bis (aminophenoxyphenyl) sulfone and 1,3-bis (3-aminophenoxy) benzene. In the general formula (2), a plurality of Ys may be the same or different between each repeating unit, and hydrogen of each benzene ring may be appropriately substituted with various substituents within a range conceivable by those skilled in the art. Can be replaced. For example, a hydrocarbon group such as a methyl group and an ethyl group and a halogen group such as Br and Cl can be exemplified, but the substituent is not limited thereto. Furthermore, among the diamine compounds represented by the general formula (2), a diamine compound having an amino group at the meta position has excellent processability due to good solubility of a thermoplastic polyimide in an organic solvent using the diamine compound. It is preferable to obtain an agent solution. The general formula (2)
May be used in combination of two or more.

The thermoplastic polyimide dissolved in the polyimide adhesive solution of the present invention can be obtained by dehydrating and ring-closing a polyamic acid polymer as a precursor thereof. This polyamic acid solution is obtained by using the above-mentioned acid dianhydride and the above-mentioned diamine compound in substantially equimolar amounts and polymerizing in an organic polar solvent.

This polyamic acid is obtained by first dissolving or diffusing a diamine compound and an acid dianhydride in an organic polar solvent in an inert atmosphere such as argon or nitrogen.

The order of addition of each component is not particularly limited. An acid dianhydride is first added to an organic polar solvent, and a diamine compound is added to form a solution of a polyamic acid polymer. A suitable amount may be added first to an organic polar solvent, then an acid dianhydride is added, and finally, the remaining diamine compound is added to form a solution of a polyamic acid polymer. There are various other polymerization methods known to those skilled in the art.

Examples of the organic polar solvent used in the reaction for producing the polyamic acid solution include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide.
Formamide solvents such as N, N-dimethylformamide and N, N-diethylformamide; acetamido solvents such as N, N-dimethylacetamide and N, N-diethylacetamide; and pyrrolidone solvents such as N-methyl-2-pyrrolidone Phenol, o-, m- or p-cresol, xinol, halogenated phenols, phenols such as catechol, or hexamethylphosphoramide, γ-butyrolactone.
Further, if necessary, these organic polar solvents can be used in combination with an aromatic hydrocarbon such as xylene or toluene.

The polyamic acid polymer obtained above is dehydrated and ring-closed by a thermal or chemical method to obtain a thermoplastic polyimide. As a method for imidation, any of a thermal method of heat-treating a polyamic acid solution and dehydration using a dehydrating agent is used, and an imidization ratio of 90% or more is essential. It is. Examples of the dehydrating agent by a chemical method include aliphatic acid anhydrides such as acetic anhydride, and aromatic acid anhydrides. Examples of the catalyst include aliphatic tertiary amines such as triethylamine, aromatic tertiary amines such as dimethylaniline, and heterocyclic tertiary amines such as pyridine and isoquinoline. The thermoplastic polyimide obtained as described above can be used as it is as a solution for preparing the polyimide adhesive solution of the present invention. Alternatively, the solvent used for the polymerization of the polyamic acid is dissolved well, but the polyimide solution is poured into a poor solvent in which the polyimide is difficult to dissolve, the polyimide resin is precipitated, the unreacted monomer is removed, purified, dried and solidified. Can be used in the adhesive solution of the present invention as appropriate. As poor solvents used, acetone, methanol, ethanol,
Isopropanol, benzene, methyl cellosolve, methyl ethyl ketone and the like.

As a thermal method, for example, there is a method in which a polyamic acid is polymerized, then put into a vacuum oven, heated under reduced pressure, imidized, and taken out as a solid polyimide resin.

The epoxy resin which can be blended in the thermoplastic polyimide solution of the present invention is not particularly limited as long as it can be dissolved in the polyimide solution. Bisphenol A type resin such as Epicoat 828 (manufactured by Yuka Shell Co., Ltd.), YX4000H
Bisphenol type resin 180S6 such as (manufactured by Yuka Shell)
Orthocresol novolak resin such as No. 5 (manufactured by Yuka Shell), bisphenol A novolak resin such as 157S70 (manufactured by Yuka Shell), trishydroxyphenylmethane novolak resin such as 1032H60 (manufactured by Yuka Shell), ESN375 and the like. Naphthalene aralkyl novolak resin, naphthalene aralkyl novolak resin such as ESN-375 (manufactured by Nippon Steel Chemical), tetraphenylolethane 1031S (manufactured by Yuka Shell), YGD414S (Toto Kasei), trishydroxyphenylmethane EPPN50
2H (Nippon Kayaku), special bisphenol VG3101L
Glycidylamine type resins such as (Mitsui Chemicals), specialty naphthol NC7000 (Nippon Kayaku), TETRAD-X, TETRAD-C (manufactured by Mitsubishi Gas Chemical Co., Ltd.) and the like are mentioned as typical examples.

The mixing ratio of the epoxy resin is preferably 1 to 50 parts by weight, more preferably 5 to 30 parts by weight, based on 100 parts by weight of the solid content of the thermoplastic polyimide resin. If the amount is too small, the adhesive strength tends to be low. If the amount is too large, flexibility and heat resistance tend to be poor.

The curing agent that can be blended with the thermoplastic polyimide solution of the present invention may be any one that is soluble in the polyimide solution, and any one that is generally used as a curing agent for epoxy resins. . The curing agent is
Water absorption, heat resistance, added to the adhesive solution for the purpose of improving the adhesiveness, etc., typically a general curing agent for epoxy such as acid dianhydride type, amine type, imidazole type, accelerator, accelerator, Alternatively, various coupling agents can be used.

The composition of the polyimide-based adhesive solution of the present invention has been described above. The concentration of the adhesive solution is represented by the solid content (thermoplastic polyimide + epoxy resin + curing agent) whose denominator is the solution weight. 5 to 50% by weight, preferably 1
It is from 0 to 40% by weight, particularly preferably from 15 to 30% by weight. The dissolution procedure and the like may be appropriately determined in consideration of workability and the like.

As a method of obtaining the film-like laminated member of the present invention, the above-mentioned polyimide adhesive solution is cast or applied on a polymer film or a metal support, and the dried adhesive coating is dried on the support. A method of obtaining a polyimide-based adhesive film by peeling or applying a polyimide-based adhesive solution to at least one surface of a polyimide film, followed by drying to obtain a polyimide-film-based film-like laminated member having a polyimide-based adhesive layer on the surface. Is mentioned. The film-like laminated member obtained in the former case is a single-layer film of a polyimide-based adhesive, which can be laminated with a polyimide film to form a film-like laminated member having the same configuration as the latter, but in any case. The thickness of the polyimide-based adhesive layer on the surface of the polyimide-film-based laminated member is suitably 5 to 30 μm. If the thickness is too small, the adhesiveness may be reduced. If the thickness is too large, it is difficult to remove and dry the organic solvent or foaming may occur.

The film-like laminated member according to the present invention obtained as described above has characteristics that can be suitably used for TAB tapes, composite lead frames, laminated materials and the like. Specifically, it shows a low water absorption, has excellent solder heat resistance, and is excellent in both heat resistance and adhesiveness, and can be bonded at a temperature of about 250 ° C. or less when used as an adhesive.

The film-shaped laminated member of the present invention can be obtained by bonding a metal foil, another film, a printed circuit board or the like to the above-mentioned film-shaped laminated member by heating and pressing. Examples of the metal foil include a copper foil, an aluminum foil, and a 42 alloy. The type of the film is not particularly limited, and examples thereof include a polyimide film and a polyester film. Conventional polyimide adhesives have insufficient adhesion to metals such as copper foil and resin films such as polyimide, and mixing with epoxy resin has been difficult due to its poor solubility. Such a film-like laminated member has excellent workability in use, such as good adhesion to a metal foil such as a copper foil or a polyimide film, and adhesion at a low temperature.
An example of the bonding condition in this case is as follows.
℃ ~ 250 ℃, pressure 0.1 ~ 10MPa, heating time 5 ~
The condition is about 20 minutes.

[0037]

(Example 1) In a glass flask having a capacity of 1000 ml, 263 g of dimethylformamide (hereinafter referred to as DMF) and 3,3'-bis (aminophenoxyphenyl) sulfone (hereinafter referred to as BAPS-M) 0.1 were added.
12 mol, and stirring under a nitrogen atmosphere.
0.112 mol of 2-bis (4-hydroxyphenyl) propanedibenzoate-3,3 ′, 4,4′-tetracarboxylic dianhydride (hereinafter referred to as ESDA) was gradually added. Stir for 30 minutes in an ice bath, viscosity 1500p
When the oil reached oise, the stirring was stopped to obtain a polyamic acid solution. 113 g of DMF and β
After adding 26 g of picoline and 45 g of acetic anhydride and stirring for 30 minutes, the mixture was further stirred at 100 ° C. for 1 hour to imidize. The solution was then dripped little by little into methanol stirred at high speed. The filamentous polyimide precipitated in methanol was pulverized with a mixer, washed with Soxhlet with methanol, and dried at 110 ° C. for 2 hours to obtain a polyimide powder. The imidation ratio of this polyimide powder is 94%
Met. In addition, it was confirmed that the solubility of the obtained polyimide in dioxolane at 20 ° C. was 10% or more.

20 g of the polyimide powder obtained above, 5 g of Epicoat 1032H60 (manufactured by Yuka Shell Co., Ltd.),
4'-diaminodiphenylsulfone (curing agent) 1.5
g was added to 102 g of THF, and dissolved by stirring. A polyimide-based adhesive solution was obtained (solid content concentration: SC
= 20%). (Example 2) A polyimide powder was obtained in the same manner as in Example 1 except that 1,3-bis (3-aminophenoxy) benzene was used as the diamine. The imidation ratio of this polyimide powder was 93%. Further, the solubility of the obtained polyimide in dioxolane at 20 ° C. is 10%.
It was confirmed that it was above. A polyimide-based adhesive solution was obtained in the same manner as in Example 1 using the obtained polyimide powder. (Example 3) A polyamic acid solution was obtained in the same manner as in Example 1. 300 g of this polyamic acid solution is placed in a vat coated with Teflon (registered trademark) and placed in a vacuum oven for 1 hour.
50 ° C for 1 hour, 180 ° C for 1 hour, 200 ° C for 3 hours, 5
It was heated under reduced pressure at a pressure of mmHg. The imidation ratio of the obtained polyimide resin was 97%. A polyimide-based adhesive solution was obtained in the same manner as in Example 1 using the obtained polyimide powder. (Example 4) 1,4 instead of THF as an organic solvent
A polyimide-based adhesive solution was obtained in the same procedure as in Example 1 except that dioxane was used (solid concentration: SC = 20)
%). Example 5 A polyimide-based adhesive solution was obtained in the same procedure as in Example 1 except that dioxolan was used instead of THF as the organic solvent (solid concentration: SC = 20%). (Example 6) The polyimide powder obtained in Example 1 was used for 20 times.
g, naphthalene aralkyl novolak resin ESN-375
5 g of Nippon Steel Chemical Co., Ltd. and 1.5 g of 4,4′-diaminodiphenylsulfone (curing agent) in 102 g of THF
To obtain a polyimide adhesive solution (solid content concentration: SC = 20%). (Example 7) The polyimide powder obtained in Example 1 was used for 20 times.
g, biphenol type epoxy resin YX4000H
5 g (manufactured by Yuka Shell Co.) and 1.5 g of 4,4′-diaminodiphenylsulfone (curing agent) in 102 g of THF
To obtain a polyimide adhesive solution (solid content concentration: SC = 20%). (Comparative Example 1) Polyamic acid solution 30 obtained in Example 1
0 g is placed on a Teflon-coated vat and placed in a vacuum oven at 150 ° C. for 1 hour, 180 ° C. for 1 hour, 5 mmH
Heated under reduced pressure at a pressure of g. The imidation ratio of the obtained polyimide resin was 75%. A polyimide-based adhesive solution was obtained in the same manner as in Example 1 using the obtained polyimide powder. (Comparative Example 2) Polyamic acid solution 30 obtained in Example 1
0 g was placed on a Teflon-coated vat and placed in a vacuum oven at 150 ° C. for 1 hour, 180 ° C. for 1 hour, and 200 ° C.
The mixture was heated under reduced pressure for 5 hours at a pressure of 5 mmHg. The imidation ratio of the obtained polyimide resin was 82%. A polyimide-based adhesive solution was obtained in the same manner as in Example 1 using the obtained polyimide powder. (Comparative Example 3) Example 1 except that the acid dianhydride component was changed to benzophenonetetracarboxylic dianhydride (BTDA).
In the same manner as above, a polyimide powder was obtained. The imidation ratio of this polyimide powder was 92%. This polyimide powder is T
It did not dissolve in HF, 1,4-dioxane, 1,3-dioxolane. (Comparative Example 4) A polyimide powder was obtained in the same manner as in Example 1, except that pyromellitic dianhydride (PMDA) was used as the acid dianhydride component and diaminodiphenyl ether (ODA) was used as the diamine component. The imidation ratio of this polyimide powder is 9
4%. This polyimide powder is THF, 1,4-
Dioxane did not dissolve in 1,3-dioxolane.

(Preparation of Film Laminated Member) The polyimide adhesive solution obtained in each example was cast on a 25 μm-thick polyimide film (Apical 25AH, manufactured by Kaneka Corporation) and dried at 100 ° C. for 10 minutes. Thereafter, the film was dried at 180 ° C. for 10 minutes to obtain a film-shaped laminated member having a thickness of 30 μm.

Comparative Examples 2 and 3 which did not dissolve
Was not prepared. (Evaluation of imidation rate of polyimide) The imidation rate is calculated from equation 1 using an infrared absorption spectroscopy. (A / B) × 100 / (C / D) Formula 1 In Formula 1, A, B, C, and D represent the following. A: absorption peak height of the object 1780 cm ^-1 B: absorption peak height of 1500 cm ^-1 of the object C: absorption peak height D of the chemical imidization of polyimide of 1780 cm ^-1: chemical imidization of polyimide 1500 cm ^- Absorption peak height of ¹ * Chemically imidized polyimide; target thermoplastic polyimide by chemical curing method at 120 ° C, 150 ° C, 200 ° C,
A polyimide subjected to an imidization reaction at 300 ° C. and 350 ° C. for 3 minutes each (this state is defined as an imidation ratio of 100%). (Evaluation of storage stability of polyimide solution) After dissolving a polyimide resin in THF at a solid content concentration of 20%, 20 # C, 6
The change in molecular weight when left for 1 month in a 0% RH environment was evaluated. ● Molecular weight evaluation GPC conditions: Column: SHOdex KF-G Mobile phase: THF Column temperature: 40 ° C. Flow rate: 1.0 ml / min. Detector: RI (Evaluation of storage stability of polyimide-based adhesive solution) After preparing a polyimide-based adhesive and leaving it for one month, a copper-clad flexible laminate was prepared using this. The peel strength of the obtained copper-clad flexible laminate was measured according to JIS C64.
81, and the change in adhesive strength before and after standing was evaluated by Autograph S-110-C (manufactured by Shimadzu Corporation). However, the conductor width was measured at 3 mm.

(Evaluation of Characteristics of Film Laminated Member) Peel Strength Measurement The peel strength when the laminated member and the copper foil were adhered was measured in the following procedure.

The film-like laminated member and the 18 μm electrolytic copper foil were heated and pressed at a temperature of 200 ° C. and a pressure of 3 MPa for 20 minutes to obtain a copper-clad flexible laminate. The peel strength of the obtained copper-clad flexible laminate was measured according to JIS C648.
Measured according to 1. However, the conductor width was measured at 3 mm.

Table 1 shows the results of evaluating the characteristics of the film-like laminated members of the examples and comparative examples.

[0044]

[Table 1]

[0045]

The polyimide solution of the present invention has excellent storage stability and does not cause a decrease in molecular weight even at room temperature.
In addition, a polyimide-based adhesive solution using this polyimide solution also exhibits excellent adhesive strength even after long-term storage.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/00 C08K 5/00 C09J 163/00 C09J 163/00 179/08 179/08 Z // B29K 79 : 00 B29K 79:00 B29L 7:00 B29L 7:00 F term (reference) 4F100 AK49B AK53B AL05B AT00A BA02 CA02B CA02H CB03B GB41 JB16B JJ03 JK13B JL11 JL12B 4F205 AA39 AA40K AG01 GA07 GB02 GE24 EL01 GF24 EG24 EG24 GF24 HA03 4J040 EC002 EH031 KA16 KA23 LA01 LA06 LA08 NA19 4J043 PA02 PA04 PA19 QB15 QB26 RA35 SA06 SB01 SB02 TA22 TA32 TB01 TB02 UA132 UA141 UA151 UA152 UA262 UB01 VA UB012 UB02A 101 UB121 UB211 XA19 YA06 YA08

Claims (10)

[Claims] 1. The method according to claim 1, wherein the imidation ratio is 90% or more, and tetrahydrofuran, 1,4-dioxane, dioxolan,
For at least one solvent selected from N, N-dimethylformamide and N, N-dimethylacetamide,
A thermoplastic polyimide solution in which a thermoplastic polyimide having a solubility at 20 # C of 10% or more is dissolved in an organic solvent, and a decrease in molecular weight after leaving for 1 month in an environment of 20 # C and 60% RH is 30% or less. A thermoplastic polyimide solution, characterized in that: 2. The thermoplastic polyimide is a polyimide made from an acid dianhydride, wherein 50 mol% or more of the total acid dianhydride is represented by the general formula (1): ## STR1 ## (Wherein, X represents — (CH ₂ ) k — or a divalent group containing an aromatic ring, and k is an integer of 1 or more and 10 or less). The thermoplastic polyimide solution according to claim 1, wherein: 3. A thermoplastic polyimide comprising an ester dianhydride represented by the above general formula (1) and the following general formula (2): (Wherein Y is the same or different, and -C (= O)-,-
SO ₂ —, —O—, —S—, — (CH ₂ ) _m —, —NHC
_{O -, - C (CH 3} ) 2 -, - C (CF 3) 2 -, - C (=
O) A bond is shown to at least one selected from O- or a single bond. m and n are integers of 1 or more and 5 or less. The thermoplastic polyimide solution according to claim 1 or 2, which is a polyimide obtained using a diamine compound represented by the formula (1) as a raw material. 4. The thermoplastic polyimide is represented by the following formula (3): 4. The polyimide solution according to claim 3, wherein the polyimide solution is obtained by using an ester dianhydride represented by the following formula and a diamine compound represented by the general formula (2) as raw materials. 5. 5. A polyimide adhesive solution obtained by mixing a thermosetting resin and a curing agent with the polyimide solution according to claim 1. 6. The polyimide adhesive solution according to claim 5, wherein the thermosetting resin is an epoxy resin. 7. The polyimide-based adhesive solution according to claim 5, wherein the decrease in molecular weight after leaving at room temperature for one month is 30% or less. 8. The polyimide-based adhesive solution according to any one of claims 5 to 7, which is cast or coated on a support,
A film-like laminated member obtained by peeling a dried adhesive coating film from a support. 9. A film-like laminate having on its surface a polyimide-based adhesive layer obtained by casting or applying the polyimide-based adhesive solution according to claim 5 on at least one surface of a polyimide film and then drying. Element. 10. The polyimide adhesive layer has a thickness of 5 to 30 μm.
The film-shaped laminated member according to claim 9, which is: