JPH047384A - Heat-resistant resin adhesive - Google Patents

Abstract

PURPOSE:To provide a resin adhesive having good flexibility and heat resistance by compounding a predetermined amount each of a specific aromatic polyimide, an end-modified imide oligomer, an epoxy compound and a bismaleimide-triazine resin. CONSTITUTION:A heat-resistant resin adhesive is prepared by compounding as resin components 100 parts by weight of a soluble aromatic polyimide (A) of a high molecular weight, 50-600 parts by weight of an end-modified imide oligomer (B) having a softening point of 300 deg.C or below, 10-200 parts by weight of an epoxy compound (C) having an epoxy group and 0-100 parts, by weight, of a bismaleimide-triazine resin (D). Component (A) is obtained by reaching a tetracarboxylic acid component containing 60mol% or more 2,3,3',4'- biphenyltetracarboxylic acid with an aromatic diamine component. Component (B) is obtained by reacting an aromatic tetracarboxylic acid component, a diamine component and a monoamine or a dicarboxylic acid component having an unsaturated group. By the use of the adhesive, adhesion of various types of metal foils and heat-resistant supporting materials may be carried out at a relatively low temp. with a good adhesive strength.

Description

Detailed Description of the Invention [Field of Industrial Application] This invention is directed to (a) a high molecular weight aromatic polyimide having no unsaturated group at its terminal, and Φ) a terminal-modified imide having an unsaturated group at its terminal. The present invention relates to a heat-resistant resin adhesive containing an oligomer, (c) an epoxy compound, and, if necessary, (d) a bismaleimide-triazine resin as resin components in a specific composition ratio.

The heat-resistant resin adhesive of the present invention can bond various metal foils such as copper foil with heat-resistant supporting materials (e.g., heat-resistant films, inorganic sheets, etc.) at a relatively low temperature, and The adhesive layer of a laminate bonded together with a flexible resin adhesive has sufficient adhesive strength and excellent heat resistance, so it can be used, for example, as a flexible wiring board,
TAB (Tape Auto+mated Bondi)
If used in the production of copper-clad boards for NG), each board obtained using the heat-resistant adhesive can be safely subjected to various high-temperature processing steps such as soldering, and the final It can improve product quality and reduce defective rates.

[Description of prior art]

Conventionally, flexible wiring boards have often been manufactured by laminating aromatic polyimide films and copper foil together using adhesives such as epoxy resins and urethane resins.

However, when flexible wiring boards manufactured using known adhesives are exposed to high temperatures during the subsequent soldering process, the adhesive layer may blister or peel. It was hoped that improvements would be made.

Imide resin adhesives have been proposed as heat-resistant adhesives, and for example, preliminary wire hardware made of N,N'-(4,4''-diphenylmethane) bismaleimide and 4,4''-diaminodiphenylmethane is known. However, this preliminary wire hardware itself is brittle and is therefore not suitable as an adhesive for flexible circuit boards.

As a method to improve the above-mentioned drawbacks, an adhesive film (dry film) is formed from a resin composition in which an aromatic polyimide obtained from benzophenone tetracarboxylic acid and an aromatic diamine is mixed with polybismaleimide. 1. The method of sandwiching the lume between a heat-resistant film such as a polyimide film and copper foil and bonding them under heat is 1. y has been done. (Refer to JP-A No. 62-232475 and JP-A No. 62-235382.) However, the above-mentioned adhesive film has a softening point of 180°C or higher, and the adhesion between the polyimide film and the copper foil is approximately 26
At a high temperature of about 0 to 280℃, and about 30 to 6
It is necessary to carry out under high pressure of about 0kg/Cf11,
Under such bonding conditions, it is extremely difficult to continuously laminate the polyimide film and the copper foil using an organic resin pressure roll, which poses a problem in terms of practicality.

[Problems to be solved by the present invention]

An object of the present invention is to provide a heat-resistant resin adhesive with a low softening temperature, which solves the problems with the known adhesives mentioned above, and which can suitably bond heat-resistant films and various metal foils together. is considered to be gigantic.

[Means for solving problems]

This invention provides (a) 100% by weight of a soluble, high molecular weight aromatic polyimide obtained from a tetracarboxylic acid component containing 60 mol% or more of 213.3',4''-biphenyltetracarboxylic acids and an aromatic diamine component. part, shi) A terminal-modified imide oligomer 50 to 600 having a softening point of 300°C or less obtained by reacting an aromatic tetracarboxylic acid component, a diamine component, and a monoamine or dicarboxylic acid component having an unsaturated group. parts by weight, preferably 60
~500 parts by weight, (c) 10 to 200 parts by weight, preferably 20 to 150 parts by weight of an epoxy compound having an epoxy group, and (b) 0 bismaleimide-triazine resin.
The present invention relates to a heat-resistant resin adhesive characterized in that the present invention contains ~100 parts by weight, preferably 0 to 80 parts by weight, as a resin component.

In this invention, the soluble, high molecular weight aromatic polyimide used as the resin component is, for example, 2.3.3'
, about 60 mol% of 4”-biphenyltetracarboxylic acids
or more, preferably 80 mol% or more, particularly preferably 90 mol% or more
A tetracarboxylic acid component containing ~100 mol% and an aromatic diamine are used as monomer components in approximately equimolar amounts to produce phenolic solvents, amide solvents, solvents for compounds having sulfur atoms, glycol solvents, alkyl solvents, etc. Both monomer components are mixed in an organic polar solvent such as a urea solvent at high temperature (
It is an aromatic polyimide having no unsaturated group at its terminal, obtained by a manufacturing method of polymerization and imidization (particularly preferably at a temperature of 140°C or higher), and a logarithm corresponding to the degree of polymerization of the polymer. Viscosity (measured concentration; 0.
5 g/100mf Solvent, Solvent: N-methyl-2-pyrrolidone, Measurement temperature: 3o''C) is 0.1 to 7, especially 0
．． It is a polymer with a fairly high molecular weight of about 2 to 6, more preferably about 0.3 to 5, and furthermore, at least 3% by weight, especially 5% by weight, of the above-mentioned organic polar solvent (especially amide solvent). A soluble aromatic polyimide that can be uniformly dissolved at a concentration of about 40% by weight is preferred.

Further, as a method for producing the above-mentioned high molecular weight aromatic polyimide, the above-mentioned tetracarboxylic acid component and aromatic diamine component are polymerized in an organic polar solvent at a low temperature of 0 to 80°C.
A method for producing a soluble aromatic polyimide by producing the obtained aromatic polyamic acid with a high molecular weight (logarithmic viscosity of at least 0.1), and imidizing the polyamic acid by any known method, the method comprising: Good too.

Expressed in another way, the high molecular weight aromatic polyimide has the following formula: - Formula I (wherein - In Formula I, Ar is a divalent residue of an aromatic diamine excluding two amino groups. ) has at least 60 mol %, particularly 80 mol % or more, more preferably 90 to 100 mol % of repeating units represented by It is preferable to use an aromatic polyimide having a high molecular weight (having a logarithmic viscosity of 0.3 to 5, particularly 0.35 to 4) and having no unsaturated groups at both ends.

The above-mentioned aromatic polyimide has an imidization rate of 90% or more, particularly 95% or more as measured by infrared absorption spectroscopy, or has an absorption peak related to the amide-acid bond of the polymer in infrared absorption spectroscopy. It is preferable that the imidization rate is so high that no absorption peaks are observed and only absorption peaks related to imide ring bonds are observed.

The above-mentioned 2.3.3',4'-biphenyltetracarboxylic acids (c) 2,3.3',4''-biphenyltetracarboxylic acid, its acid dianhydride, or its lower alkyl ester, halogen Among them, 2,3.3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) is particularly suitable.

In the heat-resistant resin adhesive of the present invention, when the aromatic polyimide is produced mainly from tetracarboxylic acids other than 2.3.3',4''-biphenyltetracarboxylic acids, the aromatic Group polyimides are not suitable because they are poorly soluble in organic polar solvents and have low compatibility with the terminal-modified imide oligomers.

Examples of tetracarboxylic acid compounds that can be used together with a-BPDA and the like as the tetracarboxylic acid component used in the production of the above-mentioned high molecular weight aromatic polyimide include 3,3", 4,4'-biphenyl. Theracarboxylic acid, 3.3',4.4'-benzophenonetetracarboxylic acid, 3.3',4.4'-diphenyl ethertetracarboxylic acid, bis(3,4-dicarboxyphenyl)methane, 2,2- Preferred examples include bis(3,4-dicarboxyphenyl)propane, pyromellitic acid, and acid dianhydrides and esters thereof.

Examples of the aromatic diamine component used in the production of the above-mentioned high molecular weight aromatic polyimide include (a) biphenyl diamine compounds, diphenyl ether diamine compounds, benzophenone diamine compounds, diphenyl sulfone diamine compounds, and diphenylmethane diamine compounds; ,2
, diphenylalkane-based diamino compounds such as 2-bis(phenyl)propane! , 2.2-bis(phenyl)hexafluoropropane-based diamine compounds, diphenylene sulfone-based diamine compounds, (b) di(phenoxy)benzene-based diamine compounds,
Di(phenyl)benzene diamine compound, (c)
r Aromatic rings (benzene rings, etc.) such as di(phenoxyphenyl)hexafluoropropane diamine compounds, di(phenoxyphenyl)propane diamine compounds, di(phenoxyphenyl)sulfone diamine compounds, etc.
Examples include aromatic diamines mainly containing "aromatic diamine compounds having 2 or more, especially 2 to 5," and they can be used alone or as a mixture.

Examples of the aromatic diamine component include diphenyl ether diamine compounds such as 1,4-diaminodiphenyl ether and 1,3-diaminodiphenyl ether;
, 3-di(4-aminophenoxy)benzene, R4-di(4-aminophenoxy)benzene and other di(phenoxy)benzene-based diamine compounds, 2.2-di(4-(4-aminophenoxy)benzene,
-aminophenoxy)phenyl]propane, di(phenoxyphenyl)propane-based diamine compounds such as 2,2-di(4-(3-aminophenoxy)phenyl)propane, bis(4-(4-aminophenoxy)phenyl) Sulfone, bis(4-(3aminophenoxy)phenyl)
Preferred examples include aromatic diamines mainly containing (90 mol% or more) "aromatic diamine compounds having 2 to 4 r aromatic rings, such as di(phenoxyphenyl) sulfonic diamine compounds such as sulfones." .

The terminal-modified imide oligomer used in the heat-resistant resin adhesive of the present invention includes, for example, an aromatic tetracarboxylic acid component, a diamine component, and a monoamine or dicarboxylic acid component having an unsaturated group. The total amount of acid anhydride groups (or a pair of adjacent carboxyl groups),
First, the aromatic tetracarboxylic acid component and the diamine component are mixed in an organic polar solvent at 100° C. or lower, particularly from 0 to 60″C. to produce an oligomer J having an amide-acid bond, then react the amic acid oligomer with a monoamine or dicarboxylic acid component having an unsaturated group, and then react at a temperature of 140 to 250 °C.
obtained by heating to high temperatures.

The terminal-modified imide oligomer has a softening point of 300
℃ or less, especially 40 to 250℃1, more preferably 50 to 250℃
230°C, and the same logarithmic viscosity as above is 0.5 or less, particularly 0.01 to 0.4, more preferably 0.01 to 0.4.
It is an oligomer with a low molecular weight of about 0.3,
A terminal-modified imide oligomer having an unsaturated group at the terminal and an imide bond within the molecule is preferred.

Expressed in another way, the terminal-modified imide oligomer has the following formula: Ar2 is a divalent organic residue obtained by removing two amino groups of a diamine compound, and R8 is a monovalent organic residue obtained by removing one amino group of a monoamine compound having an unsaturated group. R2 is an organic residue obtained by removing two carboxyl groups of a dicarboxylic acid having an unsaturated group, and m and n are 1 to 5.
0, especially an integer of about 1 to 30. ) is preferably a terminal-modified imide oligomer.

The terminal-modified imide oligomer has such a high imidization rate that in infrared absorption spectroscopy, virtually no absorption peak related to the amide-acid bond of the oligomer is found, and only an absorption peak related to the imide ring bond is observed. It is preferable that there be.

The r aromatic tetracarboxylic acid component J and the r diamine component J used in the production of the terminal-modified imide oligomer are various aromatic tetracarboxylic acids already exemplified in the process for producing a high molecular weight aromatic polyimide. , and a Group I diamine compound can all be used.

In the production of the terminal-modified imide oligomer, the aromatic tetracarboxylic acid component is particularly 2,3°3',4'
- Biphenyltetracarboxylic acids such as biphenyltetracarboxylic acid, 3.3', 4.4" biphenyltetracarboxylic acid, their acid dianhydrides, or esters of these acids as the main component (80 mol) %that's all,
Particularly preferred are aromatic tetracarboxylic acid components containing 90 mol% or more), and benzophenone tetracarboxylic acids, biphenyl ether tetracarboxylic acids, bis(3,4-dicarboxyphenyl)benzenes, 2゜2 - Aromatic tetracarboxylic acid components mainly containing bis(3,4-dicarboxyphenyl)propanes, pyromellitic acids, etc. can also be used, and further,
The aromatic tetracarboxylic acid component may be a combination of biphenyltetracarboxylic acids and the other aromatic tetracarboxylic acids mentioned above.

In the production of terminal-modified imide oligomers, the diamine components include diphenyl ether diamine compounds,
diphenylsulfone diamine compounds, diphenylalkane diamine compounds, biphenyl diamine compounds,
Di(phenoxyphenyl)propane diamine compound,
Diamine components mainly containing "aromatic diamine compounds having 2 to 4 benzene rings" such as di(phenoxy)benzene diamine compounds, or 1°3-
Diamino-2-hydroxypropane, diaminoethane,
Any diamine component may be used as long as it mainly contains an "r-aliphatic diamine compound such as diaminopropane, diaminobutane, diaminopentane, etc." or a diamine component in which the above-mentioned aromatic diamine compound and aliphatic diamine compound are used in combination.

Furthermore, in the production of terminal-modified imide oligomers, as monoamine compounds having an unsaturated group as G, (a) propargylamine, 3-aminobutyne, 4-aminobutyne, 4-aminopentyne, 5-aminopentyne, 6-aminohexine, 7-aminohexine, 4-aminohexine, "Aliphatic monoamine compounds having unsaturated groups" such as amino-3-methylbutyne, allylamine, or (b) m- or p-aminostyrene, m-amino-α-methylstyrene, ■-isopropenyl-3-( 2-aminoisopropyl)benzene, 3
-Aminophenylacetylene, 4-aminophenylacetylene, and other aromatic monoamine compounds j having a monounsaturated group can be mentioned.

In addition, as a dicarboxylic acid compound having an unsaturated group,
For example, (a) maleic acid, citraconic acid, their acid anhydrides,
Their acid esters, etc., (b) pear/nicic acid, their acid anhydrides, their acid esters, etc., (c) itaconic acid,
Unsaturated dicarboxylic acids having two Ir carboxy groups adjacent to each other such as (d)tetrahydrophthalic acid, its acid anhydrides, its acid esters, etc. can be preferably mentioned. .

As the organic polar solvent used in the production of the terminal-modified imide oligomer, the same solvent as the organic polar solvent used in the production of high molecular weight aromatic polyimide can be used, such as N,N-dimethylacetamide, N,
N-diethylacetamide, N,N-dimethylformamide, N,N-diethylformamide, N-methyl-2
- Amide solvents such as pyrrolidone, dimethyl sulfoxide, diethyl sulfoxide solvents, phenolic solvents such as cresol, phenol, xylenol, acetone, methanol, ethanol, ethylene glycol, dioxane, tetrahydrofuran, etc. that have an oxygen atom in their molecules Solvents may include other solvents such as pyridine, tetramethylurea, and, if necessary, aromatic hydrocarbon-based solvents such as benzene, toluene, xylene, turgent naphtha, benzonitrile, etc. It is also possible to use a combination of organic solvents.

Examples of the epoxy compound having an epoxy group used in the heat-resistant resin adhesive of the present invention include bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, glycidyl ether type epoxy resin, and glycidyl ester type epoxy resin. epoxy resin, glycidylamine type epoxy resin, etc.
epoxy compounds having one or more epoxy groups, and a plurality of the various epoxy resins described above may be used in combination. In this invention, it is particularly preferable that the epoxy compound has a melting point of 90°C or lower, particularly about 0 to 80°C, or is liquid at a temperature of 30°C or lower.

Further, in the heat-resistant resin adhesive of the present invention, a small amount of a suitable curing agent, curing accelerator, etc. for the above-mentioned epoxy resin may be added.

Examples of the curing agent and curing accelerator for the epoxy resin include imidals, tertiary amines, triphenylphosphines, dicyandiamides, hydrazines, aromatic diamines, and organic peroxides. .

The bismaleimide-triazine resin used in the heat-resistant resin adhesive of the present invention is a known thermosetting resin composition, for example, a bismaleimide component and a triazine monomer or prepolymer component having a cyanate group. A thermosetting resin having an imide group and a triazine ring obtained from Mitsubishi Gas, which may be modified by 0 to 30% by weight with acrylic esters, divinylbenzene, styrene, triaryisocyanate, etc. Preferred examples include "rBT Resin" manufactured by Kagaku Co., Ltd.

The heat-resistant resin adhesive of the present invention has a resin component in a specific composition ratio consisting of the above-mentioned high molecular weight aromatic polyimide, a terminally modified imide oligomer, an epoxy compound, and, if necessary, a bismaleimide-triazine resin. (especially preferably 90% by weight or more, more preferably about 95 to 100% by weight) as a main component. It may be a solution composition of a heat-resistant resin adhesive uniformly dissolved in a solvent, particularly at a concentration of 3 to 50% by weight, more preferably 5 to 40% by weight. The solution composition of the heat-resistant resin adhesive preferably has a solution viscosity (at 30° C.) of about 0.1 to 20,000 voids, particularly about 0.2 to 1,000 voids.

In addition, in the heat-resistant resin adhesive of the present invention, the softening point (temperature at which softening starts on a hot plate) of the composition containing only an uncured resin component is preferably 180°C or lower, particularly 50 to 170°C or lower, and more preferably is preferably about 60 to 160°C.

The heat-resistant resin adhesive of the present invention is preferably one that can be thermally cured by heating to a curing temperature of 130 to 400°C, more preferably 140 to 350°C.

Further, the heat-resistant resin adhesive of the present invention may contain a small proportion of other thermosetting resins such as phenol resin as a resin component.

The organic polar solvent used in preparing the solution composition of the heat-resistant resin adhesive can be the organic polar solvent used in the production of the terminal-modified imide oligomer, for example, dioxane. An organic polar solvent having an oxygen atom in its molecule, such as , tetrahydrofuran, etc., can be suitably used.

The heat-resistant resin adhesive of the present invention is applied onto the surface of a heat-resistant film such as the above-mentioned resin acid aromatic polyimide film, or onto the surface of a thermoplastic resin film such as polyester or polyethylene, and the coating layer is coated with a coating layer of 60 to 140℃ 1 Especially at a temperature of 80 to 130℃ for 20 seconds to 100 minutes, especially 30
A thin film of an uncured heat-resistant resin adhesive from which the solvent has been substantially removed by drying for ~60 minutes (preferably the residual solvent content is 1% by weight or less, particularly 0.5% by weight or less). A tri-film or sheet having a thickness of about 1 to 150 μm can be formed.

In order to form a laminate such as a copper-clad board by bonding a heat-resistant film and a metal foil using the heat-resistant resin adhesive of the present invention, for example, a thin film-like heat-resistant The heat-resistant film and the metal foil are laminated at a temperature of 90 to 190°C (particularly 100 to 180°C) via a thermoplastic resin adhesive, and then the laminated film is heated to a temperature of 80 to 350°C ( 7) At temperature for 30 minutes ~
By heating for 40 hours, especially 1 to 30 hours to heat and cure the heat-resistant adhesive layer, the above-described laminate can be easily and continuously produced without any problems.

The heat-resistant resin adhesive of the present invention is suitable for bonding heat-resistant films such as aromatic polyimide films, polyamide films, polyether ether ketone films, PEEK films, and polyether sulfone films to suitable metal foils such as copper foils. It can be suitably used.

[Examples] Hereinafter, the present invention will be explained in more detail by showing examples.

In the following examples, the logarithmic viscosity (η8, h) is calculated by uniformly dissolving the aromatic polyimide or imide oligomer in N-methyl-2-pyrrolidone so that the resin component concentration is 0.5 g/100 mf solvent. Prepare a resin solution by
The solution viscosity of the solution and the solution viscosity of the solvent only at 30℃
This is the value calculated using the formula below.

The adhesive strength was measured by performing a T-peel test at a peel rate of 5011 m/min using a tensile tester manufactured by Intesco.

Example 1 [Production of terminal-modified imide oligomer A] Volume 500ml
(a) 2.313゛+ 4゛-
Biphenyltetracarboxylic dianhydride (a-BPDA)
14.71 g (0.05 mol)■)l,3-di(4
-aminophenoxy)benzene (TPE-R) 29.
23 g (0.1 mol) (c) 175.76 g of dimethylacetamide (DMAc) was charged and stirred at 50°C for 1 hour in a nitrogen stream to produce an amic acid oligomer. The temperature was raised to .degree. C., and the mixture was stirred at that temperature for 3 hours to produce an imide oligomer having an amino group at the end.

After cooling the reaction solution to 30°C, maleic anhydride (
MA) 11.77 g (0.12 mol) and 35 g of xylene were added, and the reaction solution was heated to 160°C.
Stirring was carried out for 4 hours while xylene was removed together with the generated water to produce an imide oligomer having an unsaturated group at the end.Finally, the reaction solution was cooled to 20°C and poured into water to form a powdery imide oligomer. The oligomer was precipitated, and the precipitated imide oligomer powder was filtered off, washed twice with methanol at 25° C., and dried under reduced pressure to produce terminal-modified imide oligomer A.

This terminal-modified imide oligomer A has an imidization rate of 95
% or more, and its logarithmic viscosity was 0.04.

[Production of terminal-modified imide oligomer B] Capacity 500mf
(a) 2,3.3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) 1 in a glass flask.
4.71 g (0.05 mol) co) bis(4-(4
-Aminophenoxy)phenyl]sulfone (BAPS)
43.25 g (0.1 mol) (c) 175.76 g of dimethylacetamide ('DMAc) was charged and stirred at 50°C for 1 hour in a nitrogen stream to generate an amic acid oligomer, and then the reaction solution was was heated to about 165°C, stirred at that temperature for 3 hours to produce an imide oligomer having an amino group at the end, and after cooling the reaction solution to 30°C, 11.77% of maleic anhydride was added.
A terminal-modified imide oligomer B having an unsaturated group at the terminal was produced in the same manner as the production method J of the r-terminal modified imide oligomer, except that g (0.12 mol) and 35 g of xylene were added and reacted. did.

This terminal-modified imide oligomer B has an imidization rate of 95
% or more, and its logarithmic viscosity was 0.04.

[Production method of aromatic polyimide]

In a glass flask with a capacity of 1500 mffi, (a) 2
+ 3 + 3' + 4'-Biphenyltetracarboxylic dianhydride (a-BPDA) 29.42 g
(0.1 mol) (b) 2.2-bis(4-(4-aminophenoxy)phenyl)] and stirred at 50°C for 1 hour in a nitrogen stream to produce polyamic acid, and the reaction solution The mixture was heated to about 195° C. and stirred at that temperature for 5 hours to produce an aromatic polyimide.

The reaction solution is extruded into fibers at 20"C and poured into water below room temperature to form fibers. The fibers are washed twice with methanol at 25°C and then dried under reduced pressure to create an aromatic fragrance. Group polyimides were produced.

The aromatic polyimide had an imidization rate of 95% or more and a logarithmic viscosity of 0.41.

[Preparation of heat-resistant adhesive solution composition] Capacity 500mf
In a glass flask, 40 g of the above-mentioned terminal-modified imide oligomer A, 40 g of aromatic polyimide, and epoxy resin (
Manufactured by Yuka Shell Epoxy Co., Ltd., trade name: Ebiko) 828)
20 g, curing agent = 0.3 g of 2-methyl-4-methylimidazole.

A composition (viscosity at 25°C: 11 poise) was prepared.

This solution composition maintained a uniform solution state even after being left at room temperature for one week.

[Manufacture of laminate using heat-resistant resin adhesive] The solution composition of the heat-resistant resin adhesive described above was applied to a polyimide film (manufactured by Ube Industries, trade name: UPILEX S type, thickness 75
175 μm) with a doctor blade, and then the coated layer was heated to 100 μm for 10 minutes at 60°C.
'C for 10 minutes, heated to 120℃ for IO minutes,
A heat-resistant resin adhesive layer (uncured dried layer, softening point = 140"c) with a thickness of about 25 μm is placed on the polyimide film.
) was formed.

This polyimide film having a heat-resistant resin adhesive layer and a copper foil (35 μm) are overlapped and crimped by passing between lamination rolls heated to 180°C while applying pressure. ℃ for 2 hours, 200℃ for 2 hours, 220℃ for 1 hour, 240℃ for 1 hour, and 260℃ for 10 hours to harden the heat-resistant resin adhesive layer and produce a laminate. .

The adhesive strength of the obtained laminate was measured and the results are shown in Table 1.

Examples 2 to 6 Terminal-modified imide oligomer A or B1 produced in Example 1 as shown in Table 1 Epoxy resin [Epicoat 8 manufactured by Yuka Shell Epoxy Co., Ltd.
28. Bright phase chemical phenolic novolak resin (H-
3) or manufactured by Mitsubishi Gas Chemical (trade name: Tetrarad)
C) ), bismaleimide-triazine resin [manufactured by Mitsubishi Gas Chemical (
Product name: BT resin BT-3309, viscosity at 50℃:
15 poise, Tg after curing: 240-250"C)
) and used the terminal-modified imide oligomer A or B1 aromatic polyimide, epoxy compound, curing agent, and bismaleimide-triazine resin j in the amounts shown in Table 1. A solution composition of a heat-resistant resin adhesive was prepared in the same manner as in Example 1.

A laminate was produced in the same manner as in Example 1, except that the solution composition of each heat-resistant resin adhesive produced as described above was used. The performance of the laminate is shown in Table 1.

Comparative Example 1 25 g of terminal-modified imide oligomer A produced in Example 1
A resin solution composition was prepared using only 25 g of aromatic polyimide and 100 g of dioxane, and then the resin solution composition was applied onto a polyimide film in the same manner as in Example 1, except that the resin solution composition was used. Apply and dry the adhesive layer (uncured dried adhesive layer, thickness 22
5 μm, softening point: 190°C).

We attempted to laminate a polyimide film with an adhesive layer and copper foil, but it was virtually impossible.

Comparative Example 2 As the tetracarboxylic acid component, 3,4.3', 4'-
An aromatic polyimide (logarithmic viscosity: 0.5) was produced in the same manner as in the example except that benzophenone tetracarboxylic dianhydride was used. During this production, particulate polymer was observed to be precipitated in the reaction solution due to imidization.

An attempt was made to prepare a solution composition in the same manner as in Example 1, except that the aromatic polyimide produced as described above was used, but the aromatic polyimide had low solubility in the 1,4-dioxane solvent. It also showed unsatisfactory compatibility with the terminal-modified imide oligomer A, making it impossible to easily prepare a stable and uniform resin solution.

Therefore, when the solution composition described above is applied onto a polyimide film and dried, it is possible to form an adhesive layer with a uniform thickness.Furthermore, it is also possible to manufacture a laminate. could not.

[Effects of the present invention] The heat-resistant adhesive of the present invention has flexibility and a softening point of 180°C or less, and can be used to continuously laminate various metal foils and heat-resistant films. By heating and curing at a temperature of approximately 180 to 400°C, it is possible to create a laminate bonded through a flexible adhesive layer that has a high level of adhesive strength and excellent heat resistance. It can be manufactured continuously.

Furthermore, the heat-resistant adhesive of the present invention has excellent heat resistance (excellent adhesion at temperatures of 150°C or higher) even after it is coated onto a support film from a solution composition of the heat-resistant adhesive, dried, and cured by heating. Since it has excellent flexibility and flexibility, it can be particularly suitably used as an adhesive for flexible wiring boards, copper-clad boards for TAB, etc.

Patent applicant: Ube Industries Co., Ltd.

Claims (1)

[Scope of Claims] (a) A soluble, high-molecular-weight aroma obtained from a tetracarboxylic acid component containing 60 mol% or more of 2,3,3',4'-biphenyltetracarboxylic acids and an aromatic diamine component 100 parts by weight of group polyimide, (b) terminal modification having a softening point of 300°C or less, obtained by reacting an aromatic tetracarboxylic acid component, a diamine component, and a monoamine or dicarboxylic acid component having an unsaturated group. 50 to 600 parts by weight of imide oligomer, (c) 10 to 200 parts of epoxy compound having an epoxy group
and (d) 0 to 100 parts by weight of a bismaleimide-triazine resin as a resin component.