JP5716493B2 - Method for producing polyimide film, polyimide film, and polyimide metal laminate using the same - Google Patents

Description

  The present invention relates to a method for producing a polyimide film excellent in adhesiveness, a polyimide film, and a polyimide laminate using the same.

Polyimide films are widely used in the fields of electric / electronic devices and semiconductors because they are excellent in heat resistance, chemical resistance, mechanical strength, electrical properties, dimensional stability, and the like. For example, as a flexible printed wiring board (FPC), a copper-clad laminated board formed by laminating a copper foil on one or both sides of a polyimide film is used.
Polyimide film is generally deposited on a polyimide film via an adhesive, when a metal layer is provided on the polyimide film by dry plating such as metal deposition or sputtering, or wet plating such as electroless plating on the polyimide film. Even when a metal layer is provided, a laminate having a sufficiently high peel strength may not be obtained.
Patent Document 1 discloses a polyimide containing a benzimidazole skeleton, and discloses an example in which polyimide is directly laminated on a metal foil.
Patent Document 2 describes a novel polyimide copolymer containing a benzimidazole skeleton.

US Pat. No. 5,290,909 JP 2003-277503 A

In response to the recent trend toward higher density circuit board materials, there is little change in properties due to various stresses during circuit processing, such as balance (heat resistance, mechanical strength, dimensional stability, etc.) as well as adhesive strength as polyimide film. There is a strict demand for this.
By the way, the polyimide film formed from 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and paraphenylenediamine has good solvent resistance, high balance of mechanical properties, and dimensional stability. Excellent in linearity and the coefficient of linear expansion is as small as metal. However, when applied to a metal foil laminate such as a circuit board, it does not have sufficient adhesive force.
Then, the objective of this invention is providing the method for obtaining the polyimide film which is excellent in adhesiveness, especially adhesiveness with an adhesive agent. In particular, the present invention relates to greatly improving adhesiveness without greatly changing the general characteristics of a polyimide film composed of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and paraphenylenediamine. Furthermore, it is providing the polyimide metal laminated body obtained by laminating | stacking metal foil through a laminated body of a polyimide film and an adhesive agent, and an adhesive bond layer.

  The present invention is a polyimide obtained by mixing an aromatic tetracarboxylic dianhydride containing 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and a diamine component containing a diamine compound represented by the formula (1). A step of forming a precursor solution, a step of casting and heating the polyimide precursor solution on a support to form a self-supporting film, and a step of heating and imidizing the self-supporting film. It is a manufacturing method of the polyimide film containing.

（式（１）中、Ａはアミノ基、フェニル基、アミノフェニル基およびジアミノフェニル基から選択される基を示し、アミノ基、フェニル基、アミノフェニル基およびジアミノフェニル基の水素原子は、それぞれアルキル基で置換されていても良い。ＢとＣは、独立してアミノ基および水素原子から選ばれる基を示す。）
前記態様において、前記イミド化する工程の最高加熱温度が３５０℃以上であることが好ましい。これにより、接着剤との接着強度が大きいポリイミドフィルムを得ることができる。
また、前記イミド化する工程の最高加熱温度が４５０℃以上であることが好ましい。これにより、特に、ポリイミドフィルムのＡ面側（ポリイミド前駆体溶液を支持体上に流延して自己支持性フィルムを形成する工程において、空気側の面（支持体に接していない面）に接着剤を接着した場合に接着強度が大きいポリイミドフィルムを得ることができる。
さらに、式（１）で示すジアミン化合物は、２−（４’−アミノフェニル）−５−アミノベンゾイミダゾールであることが好ましい。
また、前記ジアミン成分は、４，４’−オキシジアニリンを含まないことが好ましい。
本発明は、３，３’，４，４’−ビフェニルテトラカルボン酸二無水物を含むテトラカルボン酸二無水物成分と、前記式（１）で示すジアミン化合物を含むジアミン成分（ただし、４，４’−オキシジアニリンを除く）と得られることを特徴とするポリイミドフィルムである。これにより、接着性に優れたポリイミドフィルムを得ることができる。
また、前記ポリイミドフィルムは、前記製造方法による得たものであることが好ましい。
さらに、式（１）で示すジアミン化合物は、２−（４’−アミノフェニル）−５−アミノベンゾイミダゾールであることが好ましい。
また、ポリイミドは、ジアミン成分としてさらにフェニレンジアミンを含むことが好ましい。これにより、耐溶媒性、力学的特性、寸法安定性、線膨張係数が金属並みに小さいなど諸特定のバランスが取れたポリイミドフィルムを得ることができる。
また、ポリイミドは、引張り破断強度が４５０ＭＰａ以上であることが好ましい。式２を含むポリイミドフィルムの引張り破断強度は、含まないそれと比べて、飛躍的に大きくなる。
本発明は、上記ポリイミドフィルムに、接着層を介して金属層を積層したポリイミド金属積層体である。

(In the formula (1), A represents a group selected from an amino group, a phenyl group, an aminophenyl group and a diaminophenyl group, and the hydrogen atoms of the amino group, the phenyl group, the aminophenyl group and the diaminophenyl group are each an alkyl group. (B and C each independently represents a group selected from an amino group and a hydrogen atom.)
In the above aspect, the maximum heating temperature in the imidizing step is preferably 350 ° C. or higher. Thereby, the polyimide film with high adhesive strength with an adhesive agent can be obtained.
Moreover, it is preferable that the maximum heating temperature of the process to imidize is 450 degreeC or more. Thereby, in particular, it adheres to the A side of the polyimide film (in the step of casting the polyimide precursor solution on the support to form a self-supporting film, the surface on the air side (the surface not in contact with the support)) When the agent is bonded, a polyimide film having a high adhesive strength can be obtained.
Furthermore, the diamine compound represented by the formula (1) is preferably 2- (4′-aminophenyl) -5-aminobenzimidazole.
Moreover, it is preferable that the diamine component does not contain 4,4′-oxydianiline.
The present invention relates to a tetracarboxylic dianhydride component including 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and a diamine component including a diamine compound represented by the above formula (1) (however, 4, 4′-oxydianiline)) and a polyimide film obtained. Thereby, the polyimide film excellent in adhesiveness can be obtained.
Moreover, it is preferable that the said polyimide film is what was obtained by the said manufacturing method.
Furthermore, the diamine compound represented by the formula (1) is preferably 2- (4′-aminophenyl) -5-aminobenzimidazole.
The polyimide preferably further contains phenylenediamine as a diamine component. As a result, it is possible to obtain a polyimide film having various specific balances such as solvent resistance, mechanical properties, dimensional stability, and linear expansion coefficient as small as those of metals.
The polyimide preferably has a tensile strength at break of 450 MPa or more. The tensile rupture strength of the polyimide film containing the formula 2 is remarkably increased as compared with that not containing the polyimide film.
The present invention is a polyimide metal laminate in which a metal layer is laminated on the polyimide film via an adhesive layer.

  According to the present invention, by using an aromatic tetracarboxylic dianhydride including 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and a diamine component represented by the formula (1), adhesiveness can be obtained. In particular, a polyimide film excellent in adhesiveness with an adhesive can be obtained. In particular, it is possible to provide a polyimide film having excellent adhesion to an adhesive even after heat treatment of the polyimide film.

(Production method of polyimide film)
The polyimide film of the present invention is obtained by thermal imidization and / or chemical imidization, and when it contains a plurality of tetracarboxylic acid components and diamine components, it is block copolymerized even if it is randomly copolymerized. Or they may be used in combination.
As a method for producing the polyimide film of the present invention,
(1) A polyamic acid solution, or a polyamic acid solution composition in which an imidization catalyst, a dehydrating agent, a release aid, inorganic fine particles and the like are selected and added to a polyamic acid solution as necessary on a support in the form of a film After casting and drying by heating to obtain a self-supporting film, dehydration cyclization by heating, a method of obtaining a polyimide film by removing the solvent,
(2) A cyclization catalyst and a dehydrating agent are added to the polyamic acid solution, and the polyamic acid solution composition added by selecting inorganic fine particles and the like as necessary is cast on a support in a film form. It can be obtained by a method of obtaining a polyimide film by dehydrating and cyclizing and heat-drying as necessary to obtain a self-supporting film, and then removing the solvent and imidizing it by heating.
In the above production method, after obtaining the self-supporting film, the heating temperature is 350 ° C. or higher, more preferably 450 ° C. or higher, so that the peel strength after the heat treatment is improved.
In the said manufacturing method, when heating at the highest heating temperature, you may carry out on the support body inert to imidation reaction, and may peel off from a support body. A copper foil or the like is typically pointed out as a metal having an obstruction factor for the imidization reaction, and a stainless steel foil or an aluminum foil is preferably used. When heat treatment is carried out on a poisoned support, there are generally cases where the mechanical properties, particularly the tensile strength at break, decrease.
The polyimide film is preferably produced by casting from polyamic acid.

Specific examples of tetracarboxylic dianhydride include 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA) and pyromellitic dianhydride (PMDA). 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride (a-BPDA), oxydiphthalic dianhydride, diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride, Bis (3,4-dicarboxyphenyl) sulfide dianhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 2 , 3,3 ′, 4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, p-phenylenebis (trimellitic acid monoester acid anhydride), p-biphenylenebis (trimellitic acid monoester acid anhydride), m-terphenyl-3 , 4,3 ′, 4′-tetracarboxylic dianhydride, p-terphenyl-3,4,3 ′, 4′-tetracarboxylic dianhydride, 1,3-bis (3,4-dicarboxy) Phenoxy) benzene dianhydride, 1,4-bis (3,4-dicarboxyphenoxy) benzene dianhydride, 1,4-bis (3,4-dicarboxyphenoxy) biphenyl dianhydride, 2,2-bis [(3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 4 , 4 ′-(2,2-hexafluoroisopropylidene) diphthalic dianhydride. These may be used alone or in combination of two or more. The tetracarboxylic dianhydride to be used can be appropriately selected according to desired characteristics.
As the aromatic tetracarboxylic acid component, an acid component containing at least s-BPDA or PMDA is preferably used. For example, in 100 mol% of the acid component, s-BPDA is 50 mol% or more, more preferably 70 mol% or more. In particular, a tetracarboxylic acid component containing 75 mol% or more is preferable because the resulting polyimide film is excellent in mechanical characteristics or thermal characteristics.

  The diamine component used in the present invention includes a diamine compound represented by the formula (1).

（式（１）中、Ａはアミノ基、フェニル基、アミノフェニル基およびジアミノフェニル基から選択される基を示し、アミノ基、フェニル基、アミノフェニル基およびジアミノフェニル基の水素原子は、それぞれアルキル基で置換されていても良い。ＢとＣは、独立してアミノ基および水素原子から選ばれる基を示す。）

(In the formula (1), A represents a group selected from an amino group, a phenyl group, an aminophenyl group and a diaminophenyl group, and the hydrogen atoms of the amino group, the phenyl group, the aminophenyl group and the diaminophenyl group are each an alkyl group. (B and C each independently represents a group selected from an amino group and a hydrogen atom.)

As a specific example of the diamine compound represented by the formula (1),
Diaminobenzimidazole represented by the formula (2),
2- (aminophenyl) aminobenzimidazole represented by the formula (3),
2- (diaminophenyl) benzimidazole represented by the formula (4),
And 2-phenyl-diaminobenzimidazole represented by the formula (5). These can be used alone or in combination of two or more.

  Specific examples of the diaminobenzimidazole represented by the formula (2) include 2,4-diaminobenzimidazole and 2,5-diaminobenzimidazole.

  Specific examples of 2- (aminophenyl) aminobenzimidazole represented by the formula (3) include 2- (2′-aminophenyl) -4-aminobenzimidazole and 2- (3′-aminophenyl) -4. -Aminobenzimidazole, 2- (4'-aminophenyl) -4-aminobenzimidazole, 2- (2'-aminophenyl) -5-aminobenzimidazole, 2- (3'-aminophenyl) -5-amino Examples thereof include benzimidazole and 2- (4′-aminophenyl) -5-aminobenzimidazole.

  Specific examples of 2- (diaminophenyl) benzimidazole represented by the formula (4) include 2- (2 ′, 3′-diaminophenyl) benzimidazole and 2- (2 ′, 4′-diaminophenyl) benzo Imidazole, 2- (2 ′, 5′-diaminophenyl) benzimidazole, 2- (2 ′, 6′-diaminophenyl) benzimidazole, 2- (3 ′, 4′-diaminophenyl) benzimidazole, 2- ( 3 ', 5'-diaminophenyl) benzimidazole and the like.

As specific examples of 2-phenyl-diaminobenzimidazole represented by the formula (5),
Examples include 2-phenyl-4,5-diaminobenzimidazole, 2-phenyl-4,6-diaminobenzimidazole, 2-phenyl-4,7-diaminobenzimidazole, 2-phenyl-5,6-diaminobenzimidazole and the like. It is done.

  Among the above, 2- (aminophenyl) aminobenzimidazole is preferable, and 2- (4′-aminophenyl) -5-aminobenzimidazole represented by the formula (6) is particularly preferable. In the following, 2- (4′-aminophenyl) -5-aminobenzimidazole may be simply referred to as “DAPBI”.

As the diamine component, in addition to the diamine of formula (1), other diamine components can be used.
1) One diamine nucleus diamine such as paraphenylenediamine (1,4-diaminobenzene; PPD), 1,3-diaminobenzene, 2,4-toluenediamine, 2,5-toluenediamine, 2,6-toluenediamine, etc. ,
2) Diaminodiphenyl ethers (oxydianilines) such as 4,4′-diaminodiphenyl ether (4,4′-oxydianiline), 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4 '-Diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis (trifluoromethyl) -4,4 '-Diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane, 3,3', 5,5'-tetramethyl-4 , 4′-diaminodiphenylmethane, bis (4-aminophenyl) sulfide, 4,4′-diaminobenzanilide, 3,3′-dichlorobenzidi 3,3′-dimethylbenzidine, 2,2′-dimethylbenzidine, 3,3′-dimethoxybenzidine, 2,2′-dimethoxybenzidine, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenylether, 4 , 4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl Sulfone, 4,4′-diaminodiphenylsulfone, 3,3′-diaminobenzophenone, 3,3′-diamino-4,4′-dichlorobenzophenone, 3,3′-diamino-4,4′-dimethoxybenzophenone, 3, , 3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 4 4'-diaminodiphenylmethane, 2,2-bis (3-aminophenyl) propane, 2,2-bis (4-aminophenyl) propane, 2,2-bis (3-aminophenyl) -1,1,1, 3,3,3-hexafluoropropane, 2,2-bis (4-aminophenyl) -1,1,1,3,3,3-hexafluoropropane, 3,3′-diaminodiphenyl sulfoxide, 3,4 Two diamine diamines such as' -diaminodiphenyl sulfoxide, 4,4'-diaminodiphenyl sulfoxide,
3) 1,3-bis (3-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (3-aminophenyl) benzene, 1,4-bis (4-amino) Phenyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (3 -Aminophenoxy) -4-trifluoromethylbenzene, 3,3'-diamino-4- (4-phenyl) phenoxybenzophenone, 3,3'-diamino-4,4'-di (4-phenylphenoxy) benzophenone, 1,3-bis (3-aminophenyl sulfide) benzene, 1,3-bis (4-aminophenyl sulfide) benzene, 1,4-bis (4-aminophenyls) Fido) benzene, 1,3-bis (3-aminophenylsulfone) benzene, 1,3-bis (4-aminophenylsulfone) benzene, 1,4-bis (4-aminophenylsulfone) benzene, 1,3- Bis [2- (4-aminophenyl) isopropyl] benzene, 1,4-bis [2- (3-aminophenyl) isopropyl] benzene, 1,4-bis [2- (4-aminophenyl) isopropyl] benzene, etc. The benzene core of three diamines,
4) 3,3′-bis (3-aminophenoxy) biphenyl, 3,3′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, 4,4′-bis (4-aminophenoxy) biphenyl, bis [3- (3-aminophenoxy) phenyl] ether, bis [3- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) phenyl] ether, Bis [4- (4-aminophenoxy) phenyl] ether, bis [3- (3-aminophenoxy) phenyl] ketone, bis [3- (4-aminophenoxy) phenyl] ketone, bis [4- (3-amino Phenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] ketone, bis [3- (3-aminophenoxy) phenyl] Sulfide, bis [3- (4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [3- (3 -Aminophenoxy) phenyl] sulfone, bis [3- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, Bis [3- (3-aminophenoxy) phenyl] methane, bis [3- (4-aminophenoxy) phenyl] methane, bis [4- (3-aminophenoxy) phenyl] methane, bis [4- (4-amino Phenoxy) phenyl] methane, 2,2-bis [3- (3-aminophenoxy) phenyl] propane, , 2-bis [3- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl ] Propane, 2,2-bis [3- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [3- (4-aminophenoxy) Phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoro Four diamine diamines such as propane, 2,2-bis [4- (4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane,
And so on. These may be used alone or in combination of two or more. The diamine to be used can be appropriately selected according to desired characteristics.
As the diamine component, in addition to the diamine represented by the formula (1), a diamine component selected from PPD and diaminodiphenyl ethers, preferably any of PPD, 4,4′-diaminodiphenyl ether, or 3,4′-diaminodiphenyl ether A diamine component containing at least one kind is preferred because the resulting polyimide film is excellent in mechanical properties or thermal properties.
Moreover, a polyimide film should be produced without containing diaminodiphenyl ethers (oxydianilines) such as 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, and 3,4′-diaminodiphenyl ether as the diamine component. Can do. A polyimide film can be produced without using 4,4′-diaminodiphenyl ether (4,4′-oxydianiline) as the diamine component.
The content of the diamine represented by the formula (1) in the diamine component is more than 0 and 100 mol%, preferably 5 mol% to 100 mol%. As a diamine component, it can consist only of diamine shown by Formula (1). When only the diamine represented by the formula (1) and PPD are used as the diamine, the molar ratio of the formula (1) / PPD is preferably 100/0 to 5/95.

  As the polyimide, among them, an acid component containing s-BPDA and PMDA, a diamine represented by formula (1), or a diamine represented by formula (1), PPD, 4,4′-diaminodiphenyl ether, 3,4 Polyimides produced from diaminodiphenyl ethers such as' -diaminodiphenyl ether are preferred. In particular, for the purpose of improving dimensional stability, it is more preferable to use PPD.

  A polyamic acid (polyimide precursor) can be obtained by reacting a tetracarboxylic acid component and a diamine component by a known method using the above-mentioned components, for example, by reacting an approximately equimolar amount in an organic solvent. Thus, a polyamic acid solution (a part thereof may be imidized as long as a uniform solution state is maintained) can be obtained. Alternatively, it combines the two or more polyamic acid is excessive advance either component, after combining the respective polyamic acid solution may be mixed under reaction conditions. The polyamic acid solution thus obtained can be used for the production of a self-supporting film as it is or after removing or adding a solvent if necessary.

  As an organic solvent of the polyamic acid solution or the polyimide solution, a known solvent can be used, for example, N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide. N, N-dimethylimidazolidinone and the like. These organic solvents may be used alone or in combination of two or more.

In carrying out the polymerization reaction of the polyamic acid and the polyimide, the concentration of all monomers in the organic polar solvent may be appropriately selected according to the purpose of use and the purpose of production. The monomer concentration is preferably 10% by mass to 30% by mass, more preferably 15% by mass to 27% by mass, and particularly preferably 18% by mass to 26% by mass.
As an example of the production of polyamic acid, the polymerization reaction of the aromatic tetracarboxylic acid component and the aromatic diamine component is, for example, substantially equimolar or either component (acid component or diamine component). The reaction is carried out at a reaction temperature of 100 ° C. or lower, preferably 80 ° C. or lower for about 0.2 to 60 hours to obtain a polyamic acid solution.

If necessary, an imidization catalyst, an organic phosphorus-containing compound, inorganic fine particles, and the like may be added to the polyamic acid solution as long as it is thermal imidization.
If it is chemical imidation, you may add a cyclization catalyst, a dehydrating agent, inorganic fine particles, etc. to a polyamic acid solution as needed.
An organic phosphorus-containing compound, inorganic fine particles, and the like may be added to the polyimide solution.

  Examples of the imidization catalyst include a substituted or unsubstituted nitrogen-containing heterocyclic compound, an N-oxide compound of the nitrogen-containing heterocyclic compound, a substituted or unsubstituted amino acid compound, an aromatic hydrocarbon compound having a hydroxyl group, or an aromatic heterocyclic compound. Cyclic compounds such as 1,2-dimethylimidazole, N-methylimidazole, N-benzyl-2-methylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 5-methylbenzimidazole and the like. Benzimidazoles such as alkylimidazole and N-benzyl-2-methylimidazole, isoquinoline, 3,5-dimethylpyridine, 3,4-dimethylpyridine, 2,5-dimethylpyridine, 2,4-dimethylpyridine, 4-n- Preferred are substituted pyridines such as propylpyridine It can be used for. The amount of the imidization catalyst used is preferably about 0.01 to 2 times equivalent, particularly about 0.02 to 1 times equivalent to the amic acid unit of the polyamic acid. By using an imidization catalyst, properties of the resulting polyimide film, particularly elongation and end resistance, may be improved.

  Examples of the organic phosphorus-containing compounds include monocaproyl phosphate, monooctyl phosphate, monolauryl phosphate, monomyristyl phosphate, monocetyl phosphate, monostearyl phosphate, triethylene glycol monotridecyl Monophosphate of ether, monophosphate of tetraethylene glycol monolauryl ether, monophosphate of diethylene glycol monostearyl ether, dicaproyl phosphate, dioctyl phosphate, dicapryl phosphate, dilauryl phosphate, dimyristyl phosphate, Dicetyl phosphate, distearyl phosphate, diethylene phosphate of tetraethylene glycol mononeopentyl ether, triethyl Diphosphate of glycol mono tridecyl ether, diphosphate of tetraethyleneglycol monolauryl ether, and phosphoric acid esters such as diphosphate esters of diethylene glycol monostearyl ether, amine salts of these phosphates. As amine, ammonia, monomethylamine, monoethylamine, monopropylamine, monobutylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, monoethanolamine, diethanolamine, triethanolamine Etc.

  Cyclization catalysts include aliphatic tertiary amines such as trimethylamine and triethylenediamine, aromatic tertiary amines such as dimethylaniline, and heterocyclic tertiary amines such as isoquinoline, pyridine, α-picoline and β-picoline. Etc.

  Examples of the dehydrating agent include aliphatic carboxylic acid anhydrides such as acetic anhydride, propionic anhydride, and butyric anhydride, and aromatic carboxylic acid anhydrides such as benzoic anhydride.

Inorganic fine particles include fine particle titanium dioxide powder, silicon dioxide (silica) powder, magnesium oxide powder, aluminum oxide (alumina) powder, inorganic oxide powder such as zinc oxide powder, fine particle silicon nitride powder, and titanium nitride powder. Inorganic nitride powder such as silicon carbide powder, inorganic carbide powder such as silicon carbide powder, and inorganic salt powder such as particulate calcium carbonate powder, calcium sulfate powder, and barium sulfate powder. These inorganic fine particles may be used in combination of two or more. In order to uniformly disperse these inorganic fine particles, a means known per se can be applied.
Instead of inorganic fine particles, polyimide fine particles insoluble in organic solvents can be used.

The self-supporting film of the polyamic acid solution should be peel-coated from the support to the extent that it becomes self-supporting by applying the polyamic acid solution onto the support (meaning the stage before the normal curing process), for example. It is manufactured by heating to such an extent that it can be produced.
The solid content concentration of the polyamic acid solution used in the present invention is not particularly limited as long as the concentration is within a viscosity range suitable for production, but is usually preferably 10% by mass to 30% by mass, and 15% by mass to 27% by mass. More preferably, 18 mass%-26 mass% is further more preferable.
The heating temperature and heating time during the production of the self-supporting film can be appropriately determined. In the thermal imidization, for example, the heating may be performed at a temperature of 100 to 180 ° C. for about 1 to 60 minutes.
The self-supporting film is not particularly limited as long as the solvent is removed and / or imidized to such an extent that it can be peeled off from the support, but in thermal imidization, the loss on heating is 20 to 50 mass. %, And when the weight loss on heating is in the range of 20 to 50% by mass and the imidization ratio is in the range of 7 to 55%, the mechanical properties of the self-supporting film are sufficient. Moreover, if the heat loss and imidation rate of the self-supporting film are within the above ranges, it is preferable because foaming, cracks, crazes, cracks, cracks and the like are not observed in the polyimide film obtained after imidization.
Here, the loss on heating of the self-supporting film is a value obtained by the following equation from the mass W1 of the self-supporting film and the mass W2 of the film after curing.
Heat loss (mass%) = {(W1-W2) / W1} × 100

The self-supporting film of the polyimide solution can be peeled off from the support, for example, by casting the polyimide solution on the support to the extent that it becomes self-supporting (meaning the stage before the normal curing step). Produced by heating to the extent.
The heating temperature and heating time during the production of the self-supporting film can be appropriately determined, and may be performed under conditions that do not impair the surface characteristics of the film.
When manufacturing a polyimide film from a polyimide solution, it may be heated at the maximum heating temperature without peeling from the support without using a self-supporting film as described above.

  The support is not particularly limited as long as it can cast a polyamic acid solution or a polyimide solution and does not affect the imidization reaction, but it is preferable to use a smooth substrate, for example, a metal drum such as stainless steel, A belt or the like is used.

In the present invention, the self-supporting film can then be heat-treated to obtain a polyimide film, and the maximum heating temperature is 350 ° C. or higher, preferably 450 ° C. or higher, more preferably 470 ° C. or higher. The upper limit may be a temperature at which the properties of the polyimide film do not deteriorate, preferably 600 ° C. or less, more preferably 550 ° C. or less, further preferably 530 ° C. or less, and particularly 520 ° C. or less.
In the heat treatment, it is appropriate to first gradually perform imidization of the polymer and evaporation / removal of the solvent at a temperature of about 100 ° C. to less than 350 ° C. for about 0.05 to 5 hours, particularly 0.1 to 3 hours. is there. In particular, the heat treatment is performed stepwise at a relatively low temperature of about 100 ° C. to about 170 ° C. for about 0.5-30 minutes, and then at a temperature above 170 ° C. and below 220 ° C. It is preferable that the second heat treatment is performed for 0.5 to 30 minutes, and then the third heat treatment is performed at a high temperature exceeding 220 ° C. and less than 350 ° C. for about 0.5 to 30 minutes. It is necessary to perform the fourth high-temperature heat treatment at a high temperature of ℃ or less. Also, this heating process can be performed sequentially or continuously.
During the heat treatment, in the curing furnace, fix at least the edges of the long solidified film in the direction perpendicular to the longitudinal direction, that is, the width direction of the film, with pin tenters, clips, frames, etc. Heat treatment may be performed by expanding or contracting in the direction or the length direction.

  The polyimide film of the present invention may be further subjected to a surface treatment such as a sand blast treatment, a corona treatment, a plasma treatment or an etching treatment.

(Polyimide film)
Polyimide is composed of an aromatic tetracarboxylic dianhydride component including 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and a diamine component including a diamine compound represented by formula (1) (however, a diamine component) And 4,4′-oxydianiline are removed). The reason for the polyimide film of the present invention is superior to alkali resistance compared to general aromatic polyimides, although the reason is not clear.

（式（１）中、Ａはアミノ基、フェニル基、アミノフェニル基およびジアミノフェニル基から選択される基を示し、アミノ基、フェニル基、アミノフェニル基およびジアミノフェニル基の水素原子は、それぞれアルキル基で置換されていても良い。ＢとＣは、独立してアミノ基および水素原子から選ばれる基を示す。）

(In the formula (1), A represents a group selected from an amino group, a phenyl group, an aminophenyl group and a diaminophenyl group, and the hydrogen atoms of the amino group, the phenyl group, the aminophenyl group and the diaminophenyl group are each an alkyl group. (B and C each independently represents a group selected from an amino group and a hydrogen atom.)

The explanation of the aromatic tetracarboxylic dianhydride component including 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and the diamine compound represented by the formula (1) is as described above. .
The thickness of the polyimide film is not particularly limited, but is 3 to 120 μm, preferably 4 to 75 μm, and more preferably 5 to 60 μm.
The polyimide film has a tensile breaking strength of 450 MPa or more, preferably 500 MPa or more. According to the present invention, a polyimide film having mechanical properties such as tensile elongation at break and tensile strength at break, high heat resistance, and dimensional stability similar to metal can be produced.

The linear expansion coefficient of the polyimide film may be appropriately selected according to the purpose of use. For example, FPC, TAB, COF, insulating substrate materials such as metal wiring base materials, metal wiring, cover such as chip members such as IC chips, etc. When used for a substrate, etc., it is generally preferred that the linear expansion coefficient of the polyimide film is close to the linear expansion coefficient of a chip member such as a metal wiring or IC chip. Specifically, both MD and TD are 40 ppm. / ° C. or less is preferable, 0 to 30 ppm / ° C. is more preferable, 5 to 25 ppm / ° C. is further preferable, and 8 to 20 ppm / ° C. is particularly preferable.
In some applications, such as COF and interposer, the linear expansion coefficient of the polyimide film is preferably close to that of glass or silicon. According to the present invention, a polyimide film having a linear expansion coefficient of 0 to 10 ppm / ° C. can also be obtained.

(Polyimide metal laminate)
The polyimide metal laminated body which laminated | stacked the metal layer on the polyimide film through the contact bonding layer is demonstrated.
The surface of the polyimide film is excellent in adhesiveness with the adhesive. Therefore, an adhesive layer can be provided directly on the polyimide film, and the initial peel strength of the polyimide film and the adhesive layer is excellent, the peel strength is excellent even after high temperature treatment, and the effect of improving or reducing the peel strength is small. The polyimide laminated body which has can be obtained.

  The polyimide laminate further laminates other substrates such as ceramics such as glass substrates and silicon wafers, metal foils, resin films; woven fabrics and nonwoven fabrics such as carbon fibers, glass fibers, and resin fibers, through an adhesive layer. be able to. Another base material can be directly laminated | stacked with the adhesive bond layer of a polyimide laminated body using a pressurization member or a heating and pressurization member. Moreover, a polyimide film and another base material can be laminated | stacked through an adhesive bond layer using a pressurization member or a heating and pressurization member.

  Examples of the pressure member or heating / pressure member include a pair of pressure-bonding metal rolls (the pressure-bonding part may be made of metal or ceramic sprayed metal), a double belt press, and a hot press. Among them, those that can be cooled are preferable, and a hydraulic double belt press is particularly preferable.

The polyimide film has good adhesiveness and adhesion, and other than the above, a photosensitive material, a thermocompression bonding material, and the like can be directly laminated.
The adhesive to be used is not particularly limited as long as it is a heat-resistant adhesive such as polyimide, epoxy, acrylic, polyamide, or urethane used in the electric / electronic field. For example, polyimide adhesive, Examples thereof include heat-resistant adhesives such as epoxy-modified polyimide adhesives, phenol-modified epoxy resin adhesives, epoxy-modified acrylic resin adhesives, and epoxy-modified polyamide adhesives.
The adhesive can be provided by an arbitrary method implemented in the electronic field itself. For example, an adhesive solution may be applied to a polyimide film and dried, or a separately formed film adhesive is bonded. May be.

Examples of the metal foil include a single metal or an alloy, such as copper, aluminum, gold, silver, nickel, and stainless steel, but copper foils such as rolled copper foil and electrolytic copper foil are preferable. The thickness of the metal foil is not particularly limited, but is preferably 0.1 μm to 10 mm, particularly 7 to 60 μm.
In the case of using an extremely thin substrate having a thickness of 1 to 10 μm, a metal or resin carrier can be used in order to improve the handleability.

  The polyimide film, polyimide metal laminate and polyimide laminate of the present invention are printed wiring boards, flexible printed circuit boards, TAB tapes, COF tapes or metal wirings, and covers such as metal wirings and chip members such as IC chips. It can be used as a material for electronic parts such as base materials such as base materials, liquid crystal displays, organic electroluminescence displays, electronic paper, and solar cells, and electronic devices.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

The physical properties of the polyimide film were evaluated according to the following methods.
a) The peel strength is a peel strength at 90 ° peel, and was measured at a peel rate of 50 mm / min in an environment of a temperature of 23 ° C. and a humidity of 50%.
b) As for the surface of the polyimide film, the surface on the air side when the polyamic acid solution was cast on the support was the A surface, and the surface on the support side was the B surface.
c) In the column of the peeling strength of the polyimide laminate and polyimide metal laminate in the table, the peeling mode between the polyimide and the adherend was observed and displayed in the table with the following contents 1) to 4).
1) Interfacial peeling of polyimide / adhesive (adhesive is clouded) and cohesive failure of adhesive.
2) Cohesive failure of the adhesive.
3) Interfacial peeling of polyimide / adhesive.
4) Adhesive becomes cloudy due to polyimide / adhesive interface peeling.

Measurement of peel strength of polyimide laminate (coverlay) (preparation of polyimide laminate)
Coverlay CVA0525KA manufactured by Arisawa Manufacturing Co., Ltd. was pressed and bonded to the polyimide film surface at 180 ° C. and 3 MPa for 30 minutes to obtain a polyimide laminate.
(Measurement of peel strength)
The peel strength of the polyimide laminate was measured and used as the initial peel strength (initial A).
The polyimide laminate was treated in a hot air drier at 150 ° C. for 24 hours, and then the peel strength was measured to obtain the peel strength after heat resistance (after heat resistance A).

[Preparation of polyamic acid solution]
(Preparation of polyamic acid solution A)
A predetermined amount of N, N-dimethylacetamide (DMAc) and 2- (4′-aminophenyl) -5-aminobenzimidazole (DAPBI) were added to the polymerization tank. Thereafter, while stirring at 30 ° C., 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA) was added to DAPBI stepwise to an approximately equimolar amount to cause a reaction. A polyamic acid polymerization solution (polyimide precursor solution) having a content of 18% by mass was obtained. And the monostearyl phosphate ester triethanolamine salt was added to this polyamic acid polymerization solution in the ratio of 0.25 mass part with respect to 100 mass parts of polyamic acid, and it mixed uniformly, and the polyamic acid solution A was obtained. . The polyamic acid solution A does not contain any other diamine other than DAPBI (DAPBI 100%). The rotational viscosity of the polyamic acid solution A at 30 ° C. was 120 Pa · s.

(Preparation of polyamic acid solution B)
A predetermined amount of N, N-dimethylacetamide (DMAc), paraphenylenediamine (PPD), 2- (4′-aminophenyl) -5-aminobenzimidazole (DAPBI) was added to the polymerization tank. In all diamine components, the amount of DAPBI was 33 mol% and the amount of PPD was 67 mol%. Thereafter, while stirring at 30 ° C., 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA) was added to the total diamine component stepwise to approximately equimolar amounts, and reacted. A polymerization solution (polyimide precursor solution) of polyamic acid having a partial concentration of 18% by mass was obtained. And the monostearyl phosphate ester triethanolamine salt was added to this polyamic acid polymerization solution in the ratio of 0.25 mass part with respect to 100 mass parts of polyamic acid, and it mixed uniformly, and the polyamic acid solution B was obtained. . The rotational viscosity of the polyamic acid solution B at 30 ° C. was 250 Pa · s.

(Preparation of polyamic acid solution C)
A polyamic acid solution C was obtained in the same manner as in the preparation of the polyamic acid solution B except that the amount of DAPBI was 20 mol% and the amount of PPD was 80 mol% in all diamine components. The rotational viscosity of the polyamic acid solution C at 30 ° C. was 350 Pa · s.

(Preparation of polyamic acid solution D)
A polyamic acid solution D was obtained in the same manner as in the preparation of the polyamic acid solution B except that the amount of DAPBI was 17 mol% and the amount of PPD was 83 mol% in all diamine components. The rotational viscosity of the polyamic acid solution D at 30 ° C. was 260 Pa · s.

(Preparation of polyamic acid solution E)
A polyamic acid solution E was obtained in the same manner as in the preparation of the polyamic acid solution B except that the amount of DAPBI was 5 mol% and the amount of PPD was 95 mol% in all diamine components. The rotational viscosity of the polyamic acid solution E at 30 ° C. was 315 Pa · s.

(Preparation of polyamic acid solution F)
A predetermined amount of N, N-dimethylacetamide (DMAc) and paraphenylenediamine (PPD) were added to the polymerization tank. Thereafter, while stirring at 30 ° C., 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA) was added to PPD stepwise to approximately equimolar and reacted. The polyamic acid solution F was obtained in the same manner as the preparation of the polyamic acid solution A. The polyamic acid solution F does not contain DAPBI as a diamine component. The rotational viscosity at 30 ° C. of the polyamic acid solution F was 200 Pa · s.

[Production of polyimide film]
Example 1
The polyamic acid solution A was cast into a thin film on a glass plate, heated at 100 ° C. for 210 seconds using a hot plate, and then peeled off from the glass plate to form a self-supporting film having a loss on heating of 44.1% by mass. Obtained. The four sides of this self-supporting film were fixed with a pin tenter, and were heated and imidized stepwise at 140 ° C., 210 ° C., 370 ° C. and 490 ° C. for 75 seconds each using an oven, and the average film thickness was 32 A polyimide film of 2 μm was obtained. In this case, the maximum heating temperature for imidization is 490 ° C. Various physical properties of the polyimide film are shown in Table 1.

(Example 2)
The average film thickness was obtained in the same manner as in Example 1 except that the hot plate was changed to 135 ° C. using the polyamic acid solution B, and heated to 140 ° C. (maximum heating temperature) over a period of about 18 minutes in the oven to 490 ° C. (maximum heating temperature). Of 21.8 μm was obtained. The heat loss of the self-supporting film was 28.6% by mass. Various physical properties of the polyimide film are shown in Table 1.

(Example 3)
A polyimide film having an average film thickness of 22.2 μm was obtained in the same manner as in Example 1 except that the hot plate was set to 135 ° C. using the polyamic acid solution C. The heat loss of the self-supporting film was 29.6% by mass. Various physical properties of the polyimide film are shown in Table 1.

Example 4
A polyimide film having an average film thickness of 26.6 μm was obtained in the same manner as in Example 3 except that the polyamic acid solution D was used. The heat loss of the self-supporting film was 26.8% by mass. Various physical properties of the polyimide film are shown in Table 1.

(Example 5)
A polyimide film having an average film thickness of 25.7 μm was obtained in the same manner as in Example 3 except that the polyamic acid solution E was used. The heat loss of the self-supporting film was 31.5% by mass. Various physical properties of the polyimide film are shown in Table 1.

(Comparative Example 1)
A polyimide film having an average film thickness of 25.1 μm was obtained in the same manner as in Example 3 except that the polyamic acid solution F was used. The heat loss of the self-supporting film was 29.1% by mass. Various physical properties of the polyimide film are shown in Table 1.

[Production of polyimide film and polyimide laminate]
(Example 6)
A polyamic acid solution A was cast into a thin film on a glass plate, heated at 100 ° C. for 210 seconds using a hot plate, and then peeled off from the glass plate to form a self-supporting film having a loss on heating of 34.5% by mass. Obtained.
The self-supporting film is face-up A, and the four sides are fixed with a pin tenter. Using an oven, it is heated to 150 ° C, 210 ° C, and 370 ° C at 50 ° C for 50 seconds step by step. (PI-1) was obtained. In this case, the maximum heating temperature for imidization is 370 ° C. Using the polyimide film (PI-1), a polyimide laminate (PI-1) in which a coverlay was laminated on the A surface was obtained in the same manner as the production of the polyimide laminate. The peel strength of the polyimide laminate (PI-1) is shown in Table 2.

(Example 7)
In the same manner as in Example 6, a self-supporting film having a loss on heating of 34.5% by mass was obtained. This self-supporting film has the B side facing up, fixed on all four sides with a pin tenter, and heated in a stepwise manner at 150 ° C, 210 ° C, and 370 ° C (maximum heating temperature) for 50 seconds step by step. To obtain a polyimide film (PI-2). Using a polyimide film (PI-2), a polyimide laminate (PI-2) in which a coverlay was laminated on the B surface was obtained in the same manner as the production of the polyimide laminate. The peel strength of the polyimide laminate (PI-2) is shown in Table 2.

(Example 8)
In the same manner as in Example 6, a self-supporting film having a loss on heating of 36.7% by mass was obtained. This self-supporting film has A side up, four sides are fixed with a pin tenter, and using an oven, step by step for 50 seconds at 150 ° C, 210 ° C, 370 ° C, and 490 ° C (maximum heating temperature). To obtain a polyimide film (PI-3). Using a polyimide film (PI-3), a polyimide laminate (PI-3) in which a coverlay was laminated on the A surface was obtained in the same manner as the production of the polyimide laminate. The peel strength of the polyimide laminate (PI-3) is shown in Table 2.

Example 9
In the same manner as in Example 6, a self-supporting film having a loss on heating of 35.8% by mass was obtained. This self-supporting film is B-side up, four sides are fixed with a pin tenter, and using an oven, step by step for 50 seconds at 150 ° C, 210 ° C, 370 ° C, and 490 ° C (maximum heating temperature). To obtain a polyimide film (PI-4). Using a polyimide film (PI-4), a polyimide laminate (PI-4) in which a coverlay was laminated on the B surface was obtained in the same manner as the production of the polyimide laminate. The peel strength of the polyimide laminate (PI-4) is shown in Table 2.

(Example 10)
A polyimide film (PI-5) was obtained in the same manner as in Example 8 except that the polyamic acid solution B was used and the hot plate was set to 135 ° C. (a loss on heating of the self-supporting film of 28.9% by mass). Then, the polyimide laminated body (PI-5) which laminated | stacked the coverlay on the A surface was obtained. The peel strength of the polyimide laminate (PI-5) is shown in Table 2.

(Example 11)
A polyimide film (PI-6) was obtained in the same manner as in Example 9 except that the polyamic acid solution B was used and the hot plate was set to 135 ° C. (a loss on heating of the self-supporting film of 29.6% by mass). Then, the polyimide laminated body (PI-6) which laminated | stacked the coverlay on the B surface was obtained. The peel strength of the polyimide laminate (PI-6) is shown in Table 2.

(Example 12)
Except having used the polyamic acid solution C, it carried out similarly to Example 10, and obtained the polyimide film (PI-7) (The heating loss of a self-supporting film 28.9 mass%). Then, the polyimide laminated body (PI-7) which laminated | stacked the coverlay on the A surface was obtained. The peel strength of the polyimide laminate (PI-7) is shown in Table 2.

(Example 13)
Except having used the polyamic acid solution C, it carried out similarly to Example 11, and obtained the polyimide film (PI-8) (The heating loss of a self-supporting film 34.2 mass%). Then, the polyimide laminated body (PI-8) which laminated | stacked the coverlay on the B surface was obtained. The peel strength of the polyimide laminate (PI-8) is shown in Table 2.

(Example 14)
A polyimide film (PI-9) was obtained in the same manner as in Example 6 except that the polyamic acid solution D was used and the hot plate was set to 135 ° C. (heat loss of self-supporting film: 25.3% by mass). Then, the polyimide laminated body (PI-9) which laminated | stacked the coverlay on the A surface was obtained. The peel strength of the polyimide laminate (PI-9) is shown in Table 2.

(Example 15)
A polyimide film (PI-10) was obtained in the same manner as in Example 7 except that the polyamic acid solution D was used and the hot plate was set to 135 ° C. (a loss on heating of the self-supporting film of 26.1% by mass). Then, the polyimide laminated body (PI-10) which laminated | stacked the coverlay on the B surface was obtained. The peel strength of the polyimide laminate (PI-10) is shown in Table 2.

(Example 16)
Except having used the polyamic acid solution D, it carried out similarly to Example 12, and obtained the polyimide film (PI-11) (The heating loss of a self-supporting film was 28.1 mass%). Then, the polyimide laminated body (PI-11) which laminated | stacked the coverlay on the A surface was obtained. The peel strength of the polyimide laminate (PI-11) is shown in Table 2.

(Example 17)
Except having used the polyamic acid solution D, it carried out similarly to Example 13, and obtained the polyimide film (PI-12) (The heating loss of a self-supporting film was 28.3 mass%). Then, the polyimide laminated body (PI-12) which laminated | stacked the coverlay on the B surface was obtained. The peel strength of the polyimide laminate (PI-12) is shown in Table 2.

(Example 18)
Except having used the polyamic acid solution E, it carried out similarly to Example 14, and obtained the polyimide film (PI-13) (The heating loss of a self-supporting film 25.9 mass%). Then, the polyimide laminated body (PI-13) which laminated | stacked the coverlay on the A surface was obtained. The peel strength of the polyimide laminate (PI-13) is shown in Table 2.

(Example 19)
Except having used the polyamic acid solution E, it carried out similarly to Example 15, and obtained the polyimide film (PI-14) (The heating loss of a self-supporting film was 26.5 mass%). Then, the polyimide laminated body (PI-14) which laminated | stacked the coverlay on the B surface was obtained. The peel strength of the polyimide laminate (PI-14) is shown in Table 2.

(Example 20)
Except having used the polyamic acid solution E, it carried out similarly to Example 16, and obtained the polyimide film (PI-15) (The heat loss of a self-supporting film was 27.0 mass%). Then, the polyimide laminated body (PI-15) which laminated | stacked the coverlay on the A surface was obtained. The peel strength of the polyimide laminate (PI-15) is shown in Table 2.

(Example 21)
Except having used the polyamic acid solution E, it carried out similarly to Example 17, and obtained the polyimide film (PI-16) (The heating loss of a self-supporting film was 28.0 mass%). Then, the polyimide laminated body (PI-16) which laminated | stacked the coverlay on the B surface was obtained. The peel strength of the polyimide laminate (PI-16) is shown in Table 2.

(Comparative Example 1)
Except having used the polyamic acid solution F, it carried out similarly to Example 14, and obtained the polyimide film (PI-17) (The heating loss of a self-supporting film 25.9 mass%). Then, the polyimide laminated body (PI-17) which laminated | stacked the coverlay on the A surface was obtained. The peel strength of the polyimide laminate (PI-17) is shown in Table 2.

(Comparative Example 2)
Except having used the polyamic acid solution F, it carried out similarly to Example 15, and obtained the polyimide film (PI-18) (The heat loss of a self-supporting film was 25.7 mass%). Then, the polyimide laminated body (PI-18) which laminated | stacked the coverlay on the B surface was obtained. The peel strength of the polyimide laminate (PI-18) is shown in Table 2.

(Comparative Example 3)
Except having used the polyamic acid solution F, it carried out similarly to Example 16, and obtained the polyimide film (PI-19) (The heating loss of a self-supporting film was 28.8 mass%). Then, the polyimide laminated body (PI-19) which laminated | stacked the coverlay on the A surface was obtained. The peel strength of the polyimide laminate (PI-19) is shown in Table 2.

(Comparative Example 4)
Except having used the polyamic acid solution F, it carried out similarly to Example 17, and obtained the polyimide film (PI-20) (The heating loss of a self-supporting film was 27.6 mass%). Then, the polyimide laminated body (PI-20) which laminated | stacked the coverlay on the B surface was obtained. The peel strength of the polyimide laminate (PI-20) is shown in Table 2.

Claims (10)

A polyimide precursor solution prepared by mixing an aromatic tetracarboxylic dianhydride containing 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and a diamine component containing a diamine compound represented by formula (1) And a process of
Casting the polyimide precursor solution onto a support and heating it to form a self-supporting film;
Heating and imidizing the self-supporting film;
including
A method for producing a polyimide film having a tensile breaking strength of 450 MPa or more .

(In the formula (1), A represents a group selected from an amino group, a phenyl group, an aminophenyl group and a diaminophenyl group, and the hydrogen atoms of the amino group, the phenyl group, the aminophenyl group and the diaminophenyl group are each an alkyl group. (B and C each independently represents a group selected from an amino group and a hydrogen atom.)   The method for producing a polyimide film according to claim 1, wherein the maximum heating temperature in the imidizing step is 350 ° C. or higher.   The method for producing a polyimide film according to claim 1, wherein a maximum heating temperature in the imidizing step is 450 ° C. or higher.   The method for producing a polyimide film according to any one of claims 1 to 3, wherein the diamine compound represented by the formula (1) is 2- (4'-aminophenyl) -5-aminobenzimidazole.   The said diamine component is a manufacturing method of the polyimide film of any one of Claim 1 to 4 which does not contain 4,4'- oxydianiline. A tetracarboxylic dianhydride component including 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and a diamine component including a diamine compound represented by formula (1) (provided that 4,4′-oxydi) A polyimide film having a tensile strength at break of 450 MPa or more obtained from (except aniline).

(In the formula (1), A represents a group selected from an amino group, a phenyl group, an aminophenyl group and a diaminophenyl group, and the hydrogen atoms of the amino group, the phenyl group, the aminophenyl group and the diaminophenyl group are each an alkyl group. (B and C each independently represents a group selected from an amino group and a hydrogen atom.)   The polyimide film of Claim 6 obtained by the manufacturing method of any one of Claim 1 to 5.   The polyimide film according to claim 6 or 7, wherein the diamine compound represented by the formula (1) is 2- (4'-aminophenyl) -5-aminobenzimidazole.   The polyimide film according to any one of claims 6 to 8, wherein the polyimide further contains phenylenediamine as a diamine component. The polyimide metal laminated body which laminated | stacked the metal layer on the polyimide film of any one of Claim 6 to 9 through the contact bonding layer.