JPH1081747A - Production of polyimides, composition and its product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyimide usable without purification, excellent in physical properties, by imidating a polyamic acid in the presence of a specific imidating agent. SOLUTION: This polyimide is efficiently obtained by imidating (B) a polyamic acid in the presence of (A) a lactone and a basic organic compound as an imidating agent. The reaction temperature is preferably 120 deg.C to 200 deg.C and the reaction time is preferably 30 minutes to five hours. In the component A, the lactone is a γ-lactone or a precursor (preferably γ-oxy valeric acid) capable of forming a γ-lactone under a reaction condition. Pyridine or triethylamine may be cited as the basic organic compound. Consequently, since the polyimide contains no substance having fear of exerting a bad influence on various physical properties, it can be used without purification.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for economically producing polyimides having excellent heat resistance by efficiently imidizing a polyamic acid.

[0002]

2. Description of the Related Art Polyimide has high heat resistance, mechanical properties, chemical resistance, electrical insulation and the like, and is widely used in industrial fields such as electric, mechanical, aviation, and electronic.

As a general method for producing a polyimide, particularly an aromatic polyimide, (1) tetracarboxylic dianhydride and an aromatic diamine are added in equimolar amounts, and N-methyl-2-
After reacting in an organic polar solvent such as pyrrolidone or N, N-dimethylacetamide at room temperature to 50 ° C. to obtain a high molecular weight polyamic acid, a poor solvent such as an alcohol is added to precipitate the polyamic acid, and the resultant is filtered off. After washing and drying, the obtained polyamic acid is heated at a high temperature of 250 ° C. or more in an oxygen-free atmosphere to cause a ring-closing dehydration reaction (imidization) to produce a polyimide powder used for powder molding and the like. . In order to obtain a high-molecular-weight polyimide powder by this production method, it is necessary to go through a high-molecular-weight polyamic acid. The use of a raw material partially converted into a carboxylic acid by decomposition or the like has a drawback that a high molecular weight polyamic acid cannot be obtained. In addition, there is a problem in that the workability is troublesome and the cost is high, for example, after the polyamic acid fine powder is separated by filtration and dried in this manner, it is subjected to a high-temperature heat treatment in an oxygen-free atmosphere.

(2) While removing water by azeotropic distillation in a phenol-based or naphthol-based solvent, the reaction between tetracarboxylic dianhydride and diamine is carried out by an imidation reaction of a high molecular weight polyamic acid or a one-step method. A method of producing a polyimide solution by performing a polycondensation reaction to precipitate and recover a polyimide powder and then dissolving it in a similar solvent again has been proposed (JP-B-47-23191, JP-A-60-19775).
No. 9, etc.) and phenolic and naphthol solvents are not suitable for general use for coating agents, adhesives, etc. because they have a bad smell and strong irritating properties on the skin.

(3) It has been proposed to chemically imidize polyamic acid in an organic polar solvent in the presence of a fatty acid such as acetic anhydride and a basic compound such as pyridine to deposit polyimide. No. 37-97).
In these polyimide production methods, a large excess of acetic anhydride of 20% or more of the amount of the organic polar solvent used is required. , Precipitated as polyimide powder,
Acetic acid, pyridine and the like have been removed and recovered (JP-A-61-95029, JP-A-1-96220).
issue).

For the polyimide soluble in an organic solvent, p
-Heating in an organic solvent in the presence of an organic acid such as toluenesulfonic acid, benzenesulfonic acid, crotonic acid, etc., and removing the by-produced water out of the system by azeotropic distillation to obtain an imidized polyamide acid It has been proposed to use a polyimide solution as a wire coating agent or an adhesive (JP-A-1-96220, JP-A-7-15750). Since an organic acid is present in the polyimide solution obtained in this manner, the molecular weight of the polyimide is reduced, and in particular, when used as an adhesive, a problem occurs in moisture resistance. It is necessary to remove the acid. For the first time after such purification, the obtained polyimide powder can be used for molding purposes or
It can be redissolved in -methyl-2-pyrrolidone or other organic polar solvents and formed into a film or used as a wire coating agent or adhesive.

(4) Casting or coating a polyamic acid in a polar organic solvent on a support, removing the organic solvent by heating, and then heating at a high temperature of 250 ° C. or higher to perform imidization most widely. This is a method for producing a polyimide film or a polyimide bonded product that has been adopted. Although it is possible to obtain a polyimide having a desired molecular weight by this production method, imidization requires high-temperature treatment in an oxygen-free atmosphere, which is disadvantageous in terms of work and cost. Further, in a polyimide bonded product, a volume shrinkage strain is generated by a dehydration reaction at the time of an imidization reaction.

[0008]

SUMMARY OF THE INVENTION The present invention provides a process for producing polyimides having excellent heat resistance which can be used without substantial purification, compositions and products thereof.

[0009]

As a result of intensive studies by the present inventors, the above object has been industrially advantageously achieved by the present invention described below. That is, this is a method for producing polyimides, which comprises imidizing a polyamic acid using a γ-lactone and a basic organic compound as an imidizing agent. The most important feature of the present invention is that the imidizing agent
-It has been found that a method for producing a polyimide having excellent physical properties without purification by imidizing a polyamic acid by using a lactone and a basic organic compound. According to the study of the present inventors, δ-lactones are also useful as imidating agents,
It has been found that γ-lactones have a higher ring closure rate and are more economically advantageous, and have reached the present invention. Further, in the present invention, the polyamic acid reacts the polyamic acid with at least one kind of tetracarboxylic dianhydrides and / or at least one kind of diamine having two or more carbon atoms,
It contains the obtained block copolymeric polyamic acid.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The present invention solves various problems that occur when imidizing a polyamic acid, and as a result of intensive studies to establish an efficient production method, as a result of the presence of lactones and basic organic compounds as imidating agents. In this method, the polyamide acid is subjected to an imidation reaction while water is removed from the system by azeotropic distillation. In the polyimide production method of the present invention, the reaction temperature used is 80 ° C. in the presence of a small amount of an imidizing agent.
To a temperature below the boiling point of the non-solvent used or the boiling point of the organic polar solvent used, preferably in the range of 120 ° C. to 200 ° C., and the reaction time is 30 minutes to 10 hours, preferably 30 minutes to 5 hours. Time is enough. In this way, when used, they do not contain substances that may adversely affect various properties such as mechanical properties such as adhesion and strength, and electrical properties such as withstand voltage. Is obtained.

Hitherto, primary fatty acid anhydrides have been effective as imidizing agents, and acetic anhydride has been particularly preferred. However, the acetic anhydride used as described above has remarkable irritation and corrosiveness. Further, it is necessary to use a large amount of the organic solvent, that is, 20% or more of the amount of the polar organic solvent. The imidizing agent of the present invention has γ
A lactone or a precursor capable of producing γ-lactone under the reaction conditions, wherein the lactone is γ-valerolactone, γ-hexanolactone, γ-heptanolactone, γ
A lactone precursor which is at least one of octanolactone, γ-nonalactone and γ-decalactone, or which forms the lactone under the reaction conditions, is a γ-oxycarboxylic acid such as γ-oxyvaleric acid or a salt thereof; It is preferable to use at least one of these. The amount used may be 0.5% by weight or more of the polyamic acid used for the polymerization. Since these lactones do not prevent the dissolution of the polyimides of the present invention, they may be used in excess. The inventors have found that polyimides having an imidation ratio of 95% or more can be easily obtained in this manner, and have reached the present invention.
Particularly desirable imidizing agents are γ-valerolactone and γ
-Hexanolactone, for example, γ-valerolactone contributes to dehydration of polyamic acid in the presence of the following basic organic compound, performs imidization and changes itself to γ-oxyvaleric acid, When water is removed from the system by azeotropic distillation, γ-oxyvaleric acid returns to γ-valerolactone again.
There is an advantage that a purification step is not required because a free acid derived from the imidizing agent and impairing the stability of the polyimide is not present in the polyimide solution as in the conventional method. Further, together with the imidizing agent, pyridine, triethylamine,
It is desirable to use a basic organic compound such as triethylenediamine, tetramethylethylenediamine, picoline, N-methylmorpholine or quinoline in an amount of about 0.2 to 2 equivalents, preferably an equivalent amount, of the imidizing agent. These may be used alone or as a mixture.

The tetracarboxylic dianhydride used in the present invention is not particularly limited, but pyromellitic dianhydride (PMDA) 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride (BTDA) 3 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (BPDA) 2,2-bis (3,4-carboxyphenyl) propane dianhydride 4,4'-(hexafluoroisopropylidene) diphthalic acid Dianhydride 3,3 ', 4,4'-biphenylethertetracarboxylic dianhydride 3,3', 4,4'-biphenylsulfonetetracarboxylic dianhydride 1,2,3,4-butenetetra Carboxylic acid dianhydride bicyclo [2,2,2] oct-7-ene-2,3,
Examples thereof include tetracarboxylic dianhydrides such as 5,6-tetracarboxylic dianhydride (BCD), which may be used alone or as a mixture.

The diamine used in the present invention is not particularly limited, but 3,3'-diaminodiphenyl ether 4,4'diaminodiphenyl ether 3,3'diaminodiphenylmethane 4,4'diaminodiphenylmethane 3,3'diamino Diphenylpropane 4,4'diaminodiphenylpropane 3,3'diaminodiphenylsulfone 4,4'diaminodiphenylsulfone 3,3'diaminodiphenylsulfide 4,4'diaminodiphenylsulfide 3,3'diamino Benzophenone 4,4'diaminobenzophenone 1-sulfo 2,4 diaminobenzene 2,4 diaminophenol 1-methoxy-2,4 diaminobenzene 3,3'-dimethyl-4,4'diaminodiphenyl ether 3,3'dimethoxy -4,4'-diaminodiphenylmethane 4,4'-diamino-3,3'5,5'-tetramethylbiphenyl paraphenylenediamine metaphenylenediamine 2,4-diaminotoluene 2,4 diaminobenzoic acid 2,6-diaminobenzoate 3,5-Diaminobenzoic acid 1,3-bis (3-aminophenoxy) benzene 1,3-bis (4-aminophenoxy) benzene 2,2-bis [4- (4-aminophenoxy) phenyl] propane bis [ 4- (3-aminophenoxy) phenyl] sulfone bis [4- (4-aminophenoxy) phenyl] sulfone 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane 9,9-bis (4 , 3-Aminophenyl) fluorene 2,6-diamino-4-trifluoromethylpyridi 1,3-bis (3-aminopropyl) -1,1,3,3
-Tetramethyldisiloxane 1,3-bis (3-aminophenoxymethyl) -1,
1,3,3-tetramethyldisiloxane 1,3-bis (aminophenyl) -1,1,3,3-tetramethyldisiloxane Diamines such as α, ω-bis (3-aminopropyl) polydimethylsiloxane And these may be used alone or as a mixture.

As a preferred organic polar solvent, N-
Methyl-2-pyrrolidone (NMP), N, N-dimethylformamide, N, N-dimethylacetamide (DMA
c), N, N-diethylacetamide, N, N, -dimethylmethoxyacetamide, imidazole, γ-butyrolactone, dimethylsulfoxide, dimethylsulfone, or the like is used alone or in combination. Depending on the use, phenols or naphthols may be used alone or in combination. In order to carry out the imidization reaction while removing by-product water out of the system by azeotropic distillation, benzene, nitrobenzene, toluene, xylene, cyclohexane, dioxane, tetralin or the like may be added to these organic polar solvents.

The polyimide produced by the method of the present invention has an imide unit comprising a group consisting of a diamine and a tetracarboxylic acid, and has a two-component homopolymer structure consisting of one kind of a diamine and a tetracarboxylic acid. Not only that, but by further adding other components, a multi-component polyimide suitable for a desired use can be obtained with a structure such as a random copolymer or a block copolymer. The polyimide of the present invention is produced as follows. The diamine and the tetracarboxylic dianhydride are combined in a polar organic solvent at 0 to 80 ° C, preferably 5 to 5 ° C.
The polyamic acid is made by reacting at a temperature of 0 ° C. It is also possible to obtain polyimide by a one-step method without going through polyamic acid, but in the one-step method, the molecular weight distribution of the obtained polyimide tends to be wide, and it is difficult to control the molecular weight, and the disadvantage that viscosity rise tends to occur was there. According to the method of the present invention via a polyamic acid whose molecular weight can be easily controlled, such a disadvantage can be solved. Further, a method of using a terminal terminator at the time of reaction for the purpose of adjusting the molecular weight of the polyamic acid and sealing the polymer molecular ends with dicarboxylic anhydride is used. It is desirable to perform end capping and imidation after obtaining a polyamic acid having a desired molecular weight. However, when obtaining a block copolymer, a low molecular weight polyamic acid or a low molecular weight polyimide is added to diamine and / or tetracarboxylic acid. It is effective to add a calculated amount of dicarboxylic anhydride together with dianhydride to adjust the molecular weight of the resulting block copolymer. Phthalic anhydride,
Dicarboxylic anhydrides such as benzophenone dicarboxylic anhydrides, maleic anhydride, methyl maleic anhydride, nadic anhydride, bicyclo [2,2,1] hept-5-ene-2,3-dicarboxylic anhydride; At least one selected from the compounds is preferred.

When producing a polyimide powder for molding,
To a polyamic acid solution polycondensed in a polar organic solvent such as dimethylacetamide, γ-valerolactone as an imidizing agent and non-solvents such as pyridine and toluene as basic compounds are added, and a temperature of 120 ° C. to 200 ° C. When the imidation reaction is performed while removing water outside the system by azeotropic distillation, a fine powdered polyimide is precipitated.By filtering and drying the polyimide, the molecular weight can be easily reduced to several tens of thousands to 300,000. A powdery polyimide resin having an imidization ratio of 95% or more can be obtained.

In the case of producing a high-strength polyimide film, the imidization reaction is carried out by adding the above-mentioned imidizing agent, basic compound and non-solvent to polyamic acid reacted in a polar organic solvent. Polymer concentration is 5
A 30% by weight polyimide solution is cast on a support,
By removing the solvent by evaporation, a polyimide film can be obtained.

The production of a film from a polyamic acid solution is as follows:
Generally, it is performed as follows. First, a polyamic acid solution is cast on a stainless steel belt or the like, and the polyamide acid film having self-supporting property is removed by heating and removing the solvent from the stainless steel belt. And dehydration ring closure to obtain a polyimide film. At the time of this solvent removal, and in the initial stage of the heat ring closure, the film breaks due to a decrease in the molecular weight of the polyamic acid and volume shrinkage, and because a high temperature is required for ring closure, deterioration due to oxidation of the film and sagging due to thermal expansion. Undesirable problems such as adhesion and breakage have occurred.

On the other hand, when a film is produced using the polyimide of the present invention, such problems hardly occur, the production of the film is easy, and no high-temperature ring closure is required. Since the equipment is inexpensive and the yield is high, there is an advantage that the production cost of the film can be significantly reduced.

In order to improve the dimensional stability, impact resistance, workability, etc. and to provide adhesiveness while satisfying the excellent heat resistance and electrical performance of the polyimide as much as possible, in addition to the two-component polyimide, A multi-component polyimide is also used.

Since the random copolymer has a tendency to converge on low properties among the components rather than having the excellent properties of each component, the block copolymer is more desirable than the random copolymer. It is preferable depending on the application from the viewpoint of designing characteristics. The block copolymerized polyimide of the present invention is produced as follows. Further, at least one kind of tetracarboxylic dianhydride and / or at least one kind of diamine are added to an organic polar solvent such as NMP in which a low molecular weight polyamic acid oligomer having a molecular weight of 2000 or less is dissolved. By reacting, block copolymer polyamic acids are produced. As an imidating agent, for example, γ
When valerolactone is added to, for example, pyridine as a basic organic compound, and heated in the presence of toluene or the like, and an imidization reaction is performed while removing water out of the system by azeotropic distillation,
Block copolymerized polyimides dissolved in NMP are obtained. Further, the molecular weight is 5,000 or less, preferably 2
An imidizing agent and a basic organic compound are added to a low-molecular-weight polyamic acid oligomer having a molecular weight of 000 or less, and imidization is performed to obtain a low-molecular-weight polyimide oligomer having a carboxylic acid terminal or an amino group terminal. Block copolymerized polyimides are obtained by adding at least one dianhydride and / or at least one diamine and performing an imidization reaction while removing water by-produced by azeotropic distillation out of the system. I can do it.
When such a method is used, partial block copolymerization polyimides are obtained because partial random copolymerization is prevented by an exchange reaction during the reaction.

With respect to polyimides for applications requiring adhesiveness, a diaminosiloxane compound, a diaminofluoro compound, a diamino-containing sulfide compound, etc. are copolymerized as a diamine component in order to impart adhesiveness and processability. It is preferable to use a terminator to block the polymer end, adjust the molecular weight to about 50,000 to 100,000, and partially crosslink by a heat treatment during or after bonding to increase the molecular weight.

For the purpose of imparting crosslinking property to the polyimide of the present invention, bicyclo [2,2,2] oct-7-ene-2,3,5,
Copolymerization of 6-tetracarboxylic dianhydride, use of maleic anhydride, nadic anhydride or 3-ethynylaniline as a terminal stopper, diamines and maleic anhydride or nadic anhydride May be blended with a bisimide obtained by reacting

These polyimides are used after being dissolved in a polar solvent such as N-methylpyrrolidone and dimethylacetamide. If necessary, a solvent used in general adhesives such as mixed xylene may be added for the purpose of lowering the viscosity.

In order to impart electrodeposition properties to the polyimides of the present invention, a block copolymerized polyimide composition solution containing 10 to 20 mol% of an aromatic diamine having a carboxyl group as a diamine component is added with a base such as triethylamine. After adding a neutral compound and heating at about 40 ° C. for 1 hour to neutralize the carboxylic acid, water can be added to prepare an electrodeposition paint. The electrodeposition paint can be subjected to anion electrodeposition, and the resulting coating film has excellent adhesion and heat resistance.

As the aromatic diamine having a carboxyl group, a compound having two amino groups and one or two carboxyl groups on an aromatic ring such as benzene, naphthalene, diphenyl and diphenyl ether is used.
Examples thereof include 2,4-diaminobenzoic acid, 2,6-diaminobenzoic acid, and 3,5-diaminobenzoic acid, but are not particularly limited to these compounds.

Metal foils and sheets such as copper foils, stainless steel sheets and 42 nickel sheets, and base films represented by polyethylene terephthalate, polyethylene-2,6-naphthalate, polyphenylene sulfide, polyethersulfone films and sheets, etc. In order to improve the chemical resistance, oxidation resistance, abrasion resistance and mechanical properties of
By coating and disposing the polyimide of the present invention on one or both surfaces of the base film, a film laminate having improved properties can be obtained. The film laminate obtained in this way is
Since the properties of the base film are improved, it can be used beyond the conventional usage limits. Examples of such uses include a plate material for a screen printing plate for screen-printing a fine solder paste on a printed board, a flexible printed board, and the like.

The polyimide coating layer of the present invention provided on the surface layer of the film laminate can be used as an adhesive layer when laminating with the same or another base film material. Examples of the application include a heat-adhesive film, a cover film to be bonded to a flexible printed circuit board and a lead frame, and the like.

A particularly useful one among these uses is a film laminate obtained by applying the polyimide of the present invention to the surface of a commercially available polyimide film. When a polyimide film is used for a printed wiring board, it is necessary to provide fine through holes at predetermined positions of the polyimide film at a predetermined pitch by a method such as chemical etching. In such a case, photosensitive dry film is used as a resist material, but generally, dry film has poor adhesion to a polyimide film, and therefore, during chemical etching, etching is performed between the polyimide film and the dry film resist. There is a problem that the liquid penetrates and it is difficult to obtain a through hole having a predetermined shape. The film laminate obtained by applying the polyimide of the present invention to a commercially available polyimide film is well-adapted to dry film and exhibits good adhesiveness, so that problems during chemical etching can be solved.

Further, examples of applications of the polyimides of the present invention include insulating layers of printed wiring circuit boards and metal-based semiconductor packages, semiconductor encapsulants combining the polyimide of the present invention with fillers such as silica particles, and the like. There is a conductive adhesive and the like in which the polyimide of the present invention is blended with conductive carbon and metal fine particles such as silver, copper and nickel, and conductive fine particles such as plastic fine particles plated with a metal such as silver and nickel.

In order to impart adhesiveness, it is preferable to use block copolymer polyimides containing 3 to 50 mol% of a siloxane compound having a diamine at both terminals as a diamine component.

A metal-based semiconductor package is suitable for high-density mounting because it can be mounted with good heat dissipation by applying an electromagnetic wave shield. However, as a dielectric layer required for a metal-based substrate, The polyimides of the present invention are preferable from the viewpoint of heat resistance and adhesive performance. The structure of the semiconductor package includes a mounted semiconductor chip,
It is composed of a conductor circuit, a plurality of external connection terminals, and a metal substrate whose necessary parts are covered with an insulation layer. The insulation layer made of polyimides is composed of one or more layers, and the conductor circuit is formed on each insulation layer. A structure that is formed and penetrates each insulating layer and is electrically connected between a plurality of conductor circuits is particularly preferable for high-density mounting.

As for the insulating layer of the metal-based printed circuit board, the polyimides of the present invention have good heat resistance and good adhesive properties. Can be obtained.

In particular, for a printed wiring circuit board for high-density mounting, a printed circuit board having a fine wiring pattern formed on a conductive substrate by an electrolytic plating method is provided on a polyimide insulating layer formed on a metal sheet. For example, heat transfer or forming a wiring pattern by photo-etching on a copper foil for a substrate with copper foil attached to an insulating layer formed on a metal sheet, By forming a thin film and then forming a wiring pattern by a photoplating method, a metal-based printed wiring circuit board having a single-layer or multilayer polyimide insulating layer can be produced.

The polyimide adhesives, coating agents, electrodeposition paints, heat-adhesive films and the like comprising the block copolymerized polyimide having a molecular weight of about 50,000 to about 100,000 according to the present invention are products of polyamic acid solutions which are currently widely used. Compared with the above, it is not gelled even when stored for a long period of time, has excellent storage stability, and does not require high-temperature heat treatment in an oxygen-free atmosphere, so that handling is very convenient. In particular, since it is possible to give a regular arrangement to the components involved in the adhesiveness, the degree of freedom in polymer design can be expanded.

[0036]

The present invention will be described below in detail with reference to examples. Note that the present invention is not limited to the following embodiments.

Example 1 5 equipped with a thermometer, a stirrer, a reflux condenser equipped with a water content receiver and a nitrogen gas inlet.
In a 00 ml four-neck separable flask, 195 g of N, N-dimethylacetamide and α, ω-bis (3-aminopropyl) polydimethylsiloxane (average molecular weight 802)
8.57 g, 21.07 g of bis [4- (4-aminophenoxy) phenyl] sulfone, 3,3 ′, 4,4′-
17.65 g of biphenyltetracarboxylic dianhydride and 0.71 g of phthalic anhydride were added, and the mixture was stirred at 10 ° C. for 1 hour and then at room temperature for 3 hours to obtain a viscous solution of polyamic acid.
Subsequently, 1.03 g of pyridine was added to the polyamic acid solution,
50 g of toluene and 1.3 g of γ-valerolactone were added,
After stirring at room temperature for 20 minutes, the temperature was raised to 160 ° C. for 1 hour,
After heating and stirring at 180 ° C. for 1 hour while removing water under reflux, the mixture was further reacted for 2 hours while removing toluene out of the system to obtain a polyimide solution.

18 μm thick copper foil (Mitsui Metals 3EC)
-HTE), cast the polyimide solution onto 240
It dried at 1 degreeC for 1 hour, and obtained the 25-micrometer-thick flexible printed circuit board of a polyimide layer. The 180 degree peel peel strength (measurement method JIS C 6471) was 1.4 kg / cm, and the peel peel strength after treatment in hot water at 85 ° C. for 30 minutes was 1.05 kg / cm.

Example 2 5 equipped with a thermometer, a stirrer, a reflux condenser equipped with a water content determination receiver, and a nitrogen gas inlet.
In a 00 ml 4-neck separable flask, 180 g of N, N-dimethylacetamide, 16.11 g of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 1,1,
0.51 g of 3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisiloxane is added, and
Stir for an hour and then at room temperature for 30 minutes. In this solution,
To the mixture were added 19.5 g of 2-bis [4- (4-aminophenoxy) phenyl] propane and 0.71 g of phthalic anhydride.
The mixture was stirred at 0 ° C. for 1 hour and then at room temperature for 3 hours to obtain a viscous solution of polyamic acid. To this polyamic acid solution, 1.48 g of γ-hexanolactone, 1.03 g of pyridine and 50 g of toluene were added and reacted in the same manner as in Example 1 to obtain a polyimide solution.

18 μm thick copper foil (Mitsui Metals 3EC)
-HTE), cast the polyimide solution onto 240
After drying at 1 ° C. for 1 hour, a flexible printed board having a polyimide layer thickness of 25 μm was obtained. The 180 degree peel strength (measurement method JIS C 6471) was 1.5 kg / cm, and the peel strength after treatment in hot water at 85 ° C for 30 minutes was 1.18 kg / cm.

Further, the polyimide surface of the flexible printed circuit board and the 42 nickel sheet having a thickness of 200 μm were overlapped, and the pressure was reduced to 20 kg / c under reduced pressure of a vacuum pump.
Pressing was performed at 270 ° C. for 1 hour at a temperature of 270 ° C. to obtain a copper / 42 nickel bonding material (for metal-based printed circuit boards). The adhesion at the copper / polyimide interface and the 42 nickel / polyimide interface was sufficient, and there was no peeling even after treatment in hot water at 85 ° C. for 30 minutes.

Comparative Example 1 A polyimide solution was obtained according to the conditions of Example 1 except that P-toluenesulfonic acid was used instead of the imidizing agent γ-valerolactone used in Example 1. In the same manner as in Example 1, a polyimide solution was cast on a copper foil having a thickness of 18 μm (3EC-HTE made by Mitsui Kinzoku) to obtain a flexible printed board having a polyimide layer having a thickness of 25 μm. The 180-degree peel strength (measurement method JIS C 6471) is 0.7 kg / cm, and the peel strength after hot water treatment at 85 ° C. for 30 minutes is 0.2 kg / cm, which cannot be put to practical use. It was standard.

Comparative Example 2 A polyimide solution was obtained under the same conditions as in Example 2 except that an equimolar amount of crotonic acid was used instead of the imidizing agent γ-hexanolactone used in Example 2. 18μm thick copper foil (Mitsui Metals 3
A polyimide solution was cast on EC-HTE) to obtain a flexible printed board having a polyimide layer thickness of 25 μm. 180 degree peel peel strength (Measurement method JIS C
6471) is 0.9 kg / cm.
The peel strength after the treatment for 0 minutes was 0.3 kg / cm, which was a level that could not be put to practical use.

Example 3 2.3 g of polystyrene particles having a particle diameter of 3 to 8 μm plated with nickel and gold were dispersed in 20 g of the polyimide solution obtained in Example 1 for 30 minutes using a sand grind mill. 80 g of the above polyimide solution was added to the dispersion, which was subsequently dispersed by a sand grind mill for 30 minutes to obtain an anisotropic conductive paint. This anisotropic conductive paint is coated on a conductive terminal portion of a flexible circuit board having a pitch of 100 μm so that a film thickness of 20 μm can be obtained.
Dried for minutes. The conductive terminal portion of the obtained flexible circuit board is overlapped with an ITO circuit glass plate having the same pitch,
260 through the cushioning polyimide film
Pressure bonding was performed at 20 ° C. and a pressure of 20 kg / cm 2 for 20 seconds. The conduction resistance between the obtained thermocompression-bonded circuits is 0.5Ω or less, and the adhesive strength after a high-temperature and high-humidity test at 60 ° C. and 90% RH for 1000 hours also shows 0.5 kg / cm or more, showing good performance. Was.

Example 4 A polyimide film obtained in Example 2 was biaxially stretched with a thickness of 50 μm and a polyphenylene sulfide film (trade name: Torelina, manufactured by Toray Industries Ltd.) was used as a base film so that a film thickness of 20 μm could be obtained on the film surface. After coating, it was dried at 110 ° C. for 20 minutes using a vacuum dryer. The obtained film laminate and a metal layer of stainless steel SUS301 having a thickness of 30 μm are adhered to each other using a hot press machine, and the obtained metal laminate is fixed to a frame of a processing stage of a YAG laser beam machine. Is moved in accordance with a plurality of patterns to be drilled, and the second harmonic (wavelength: 532 nm) of the YAG laser is incident on the fourth harmonic generation unit (comprising a nonlinear optical crystal element) as laser light from the metal layer side. This is a product processed using the fourth harmonic (wavelength 266 nm) obtained as described above. An electrode was attached to the metal layer made of stainless steel, and electrolytic polishing was performed while applying a jet at 50 ° C. to an electrolytic aqueous solution consisting of phosphoric acid and sulfuric acid to smooth the unevenness of the inner wall of the through hole of the metal layer.
The outer periphery of the metal laminate with the substrate film is supported by an adhesive on a printing frame of an aluminum square pipe, and the metal layer, which is a main component of the printing plate, is disposed on the surface of the substrate film in the metal laminate. The structure having a plurality of opening through-holes can be used as a printing plate for screen printing. Since this plate uses a polyimide resin with high heat resistance as an adhesive for the base film, it has good adhesion to the printing substrate and does not show any foaming of the adhesive during laser processing.
No bleeding of the printing ink was observed on the substrate even after continuous printing 300 times.

[0046]

The present invention has found a method for directly producing polyimides having excellent physical properties from tetracarboxylic acid and diamine using γ-lactones and basic organic compounds as imidizing agents. It is in. The resulting polyimide composition does not gel even after long-term storage, has excellent storage stability, and does not require high-temperature heat treatment in an oxygen-free atmosphere. Used in a wide range of applications such as adhesive films for flexible films, flexible printed circuit boards and cover films to be bonded to lead frames, insulating layers for printed circuit boards and semiconductor packages, semiconductor sealants, conductive adhesives, and electrodeposition paints. I can do it.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location C09J 9/02 C09J 9/02 179/08 179/08 Z H01L 23/29 H05K 1/03 610N 23 / 31 3/46 T H05K 1/03 610 N 3/46 H01L 23/30 R

Claims (15)

[Claims] 1. A method for producing polyimides, wherein a polyamic acid is imidized using a γ-lactone and a basic organic compound as an imidizing agent. 2. A block copolymer obtained by reacting the polyamic acid with at least one of tetracarboxylic dianhydride and / or at least one of diamines having two or more carbon atoms. The method for producing a polyimide according to claim 1, wherein the method is a polyamic acid. 3. The γ-lactone according to claim 1, wherein the γ-lactone is at least one lactone having the following structure.
Production method of polyimides. Embedded image 4. The method according to claim 1, wherein the basic organic compound is at least one selected from pyridine, triethylamine, tetramethylethylenediamine, triethylenediamine, picoline, N-methylmorpholine and quinoline.
A method for producing a polyimide according to any one of claims 3 to 4. 5. The method for producing polyimides according to claim 1, wherein said polyamic acid contains a diaminosiloxane compound as one component. 6. The method for producing a polyimide according to claim 1, wherein the polyamic acid contains an aromatic diaminocarboxylic acid as one component. 7. An anionic electrodeposition coating composition comprising the polyimides, organic polar solvent, amines and water of claim 6 as main components. 8. A polyimide film comprising a composition containing the polyimides according to claim 1 as a main component. 9. A film laminate comprising the substrate film on which the polyimides according to claim 1 is disposed. 10. An adhesive composition comprising the polyimides according to claim 1 and an organic polar solvent as main components. 11. A printed circuit board comprising the polyimide of any one of claims 1 to 7 as an insulating layer. 12. A printed wiring circuit board comprising a conductor circuit, a plurality of external connection terminals, and a metal substrate having a necessary portion covered with an insulating layer, wherein the polyimide insulating layer according to claim 1 is used. A printed wiring circuit board comprising one or two or more layers, wherein a conductive circuit is formed on each insulating layer, and a plurality of electrical connections are made between the conductive circuits through each insulating layer. 13. A mounted semiconductor chip, a conductor circuit,
8. A semiconductor package comprising a plurality of external connection terminals and a metal substrate having a required portion covered with an insulating layer, wherein the polyimide insulating layer according to any one of claims 1 to 7 comprises one or more layers. A semiconductor package, wherein a conductor circuit is formed on an insulating layer, and a plurality of electrical connections are made between the conductor circuits through each insulating layer. 14. A semiconductor encapsulant comprising the polyimides according to claim 1 and a filler as essential components. 15. A conductive adhesive comprising the polyimide according to claim 1 and conductive fine particles.