JP2007031622A - Polyimide resin and film with conductor using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new polyimide resin, and to provide a film with conductor using the same, for use in flexible printed wiring boards having high heat resistance and good adhesion between electrical insulation film and a conductor layer and enabling fine wiring formation. <P>SOLUTION: The new polyimide resin has recurring units whose structure is at least one shown by bicyclotetracarboxylic acid anhydride, diaminopyridine, diaminotriazine, diaminodipyridyl and diaminopyrimidine. The conductor-clad film is such that at least one side of electrical insulation film is provided with a conductor layer, wherein the above polyimide resin's layer is provided in between the electrical insulation film and the conductor layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a novel polyimide resin, and further relates to a film with a conductor using the polyimide resin which can be used as a flexible printed wiring board and has excellent adhesion between an insulating film and a conductor layer and adhesion in fine wiring.

  Polyimide resin has excellent heat resistance and good mechanical, electrical and chemical properties, and is used as an insulating material for flexible printed circuit boards (FPC), automatic tape bonding (TAB) substrates, etc. Yes. Conventionally, a flexible printed wiring board in which an aromatic polyimide film and a copper foil are bonded together with an adhesive using epoxy, acrylic, polyamide, phenol, or the like is well known. In addition, the adhesion between the film and the conductor layer made of copper foil is determined by the characteristics of the adhesive, and there is a problem particularly in terms of heat resistance. In addition, a flexible printed wiring board is known in which a thermoplastic polyimide precursor or a thermoplastic polyimide resin is used as an adhesive for improving heat resistance, and a metal foil such as a copper foil is thermocompression bonded at a high temperature. Since there is a problem of residual distortion after processing since the metal must be thermocompression bonded at a high temperature, there is a problem that patterning with a narrow pitch is difficult because the thickness of the metal foil used for pressure bonding is usually 10 μm or more (for example, patents) References 1, 2, 3, 4).

Also known is a flexible printed wiring board having a two-layer structure in which a metal layer is formed by electrolytic plating after sputtering or electroless plating of a metal directly on an insulating film such as a non-thermoplastic polyimide film or an aramid film. In general, there is a problem in that the adhesion is low and the deterioration of the adhesion after a heat load is particularly large. Also known is a flexible printed wiring board in which a thermoplastic polyimide layer is provided on a non-thermoplastic polyimide, copper is sputtered or electrolessly plated on the surface, and then a metal layer is formed by electrolytic plating (for example, Patent Documents). 5, 6) There is a problem that the adhesion force in the fine wiring is lowered.
JP-A-4-146690 Japanese Examined Patent Publication No. 7-102649 JP-A-10-75053 JP 2000-167980 A JP 2003-251773 A JP 2005-88465 A

  An object of the present invention is to provide a novel polyimide resin, and by using the polyimide resin, a conductor for a flexible printed wiring board that is excellent in heat resistance and adhesion between a conductor layer and an insulating film and capable of forming fine wiring. A film with a cover is provided.

  As a result of intensive studies to solve the above problems, the present inventor provided a specific polyimide resin layer on at least one surface of the insulating film, and formed a conductor layer on the polyimide resin layer by electroless plating and then electrolytic plating. As a result, it was found that a film with a conductor for a flexible printed wiring board excellent in heat resistance and adhesion and capable of forming fine wiring was obtained, and the present invention was achieved. That is, this invention is a polyimide resin characterized by having at least one of the structures represented by the following formulas (1) to (5) as a repeating unit.

（式中、ＲはＨ、ＣＨ_３、Ｃ_６Ｈ_５、ＯＨを表す）
また、本発明は、絶縁性フィルムの少なくとも片面に導体層を形成した導体付きフィルムにおいて、前記絶縁性フィルムと導体層との間に、上記ポリイミド樹脂の層を設けたことを特徴とする導体付きフィルムである。
また、本発明の導体付きフィルムは、前記絶縁性フィルムが、ポリエチレンテレフタレート、ポリナフタレンテレフタレート、ポリフェニレンスルフィド、ポリフェニレンエーテル系樹脂、ポリアミド系樹脂、芳香族ポリアミド系樹脂、ポリイミド系樹脂、フッ素系樹脂、液晶ポリマーのいずれかであって、厚さが１〜２００μｍであることが好ましい。
また、本発明の導体付きフィルムは、前記ポリイミド樹脂層の厚さが、０．１〜１０μｍであることが好ましい。
また、本発明の導体付きフィルムは、前記ポリイミド樹脂層の繰り返し単位の４０モル％以上が、前記式（１）乃至（５）で示される構造の少なくとも１種であることが好ましい。
また、本発明の導体付きフィルムは、前記導体層の厚さが１〜２０μｍであって、無電解メッキと電解メッキによって形成されたものが好ましい。

(Wherein R represents H, CH ₃ , C ₆ H ₅ , OH)
In addition, the present invention provides a film with a conductor in which a conductor layer is formed on at least one side of an insulating film, wherein the polyimide resin layer is provided between the insulating film and the conductor layer. It is a film.
Further, in the film with conductor of the present invention, the insulating film is made of polyethylene terephthalate, polynaphthalene terephthalate, polyphenylene sulfide, polyphenylene ether resin, polyamide resin, aromatic polyamide resin, polyimide resin, fluorine resin, liquid crystal It is any polymer and preferably has a thickness of 1 to 200 μm.
Moreover, it is preferable that the film with a conductor of this invention is 0.1-10 micrometers in thickness of the said polyimide resin layer.
Moreover, as for the film with a conductor of this invention, it is preferable that 40 mol% or more of the repeating unit of the said polyimide resin layer is at least 1 sort (s) of the structure shown by said Formula (1) thru | or (5).
Moreover, the film with a conductor of the present invention preferably has a thickness of the conductor layer of 1 to 20 μm and is formed by electroless plating and electrolytic plating.

  The polyimide resin of the present invention can firmly adhere the conductor layer and the insulating film and has excellent heat resistance. In addition, the film with a conductor obtained in the present invention is excellent in heat resistance and adhesion between the conductor layer and the insulating film, and excellent in adhesion of the conductor layer even after the fine wiring is formed. Since it is suitably used as a printed wiring board, the industrial utility of the film with a conductor of the present invention is extremely high.

[Polyimide resin]
The polyimide resin of the present invention has a structure represented by the above formulas (1) to (5) as a part of the repeating unit of the resin, and any structure is formed in the form of polyimide. Resins with excellent mechanical strength, heat resistance, and adhesion can be formed.

  More specifically, the resin having the structure of formula (1) is bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and diamine or diisocyanate. Formula (2) is from diaminopyridine and tetracarboxylic dianhydride, and Formula (3) is from diamino-1,3,5-triazine or a diamino-1,3,5-triazine derivative and tetracarboxylic dianhydride. Formula (4) can be obtained from diaminodipyridyl and tetracarboxylic dianhydride, and formula (5) can be obtained from diaminopyrimidine or a diaminopyrimidine derivative and tetracarboxylic dianhydride. These polyimides can be obtained by adding a tetracarboxylic dianhydride, a diamine, or a diisocyanate in a polar solvent and, if necessary, a heat reaction. At that time, other tetracarboxylic dianhydrides, diamines, or all tetracarboxylic dianhydrides that use diisocyanates, all diamines, or all diisocyanates can be mixed and used within 40 mol%. It is. Further, the molecular weight can be adjusted by shifting the ratio of tetracarboxylic dianhydride and diamine or diisocyanate within the range of 10 mol% or less, and can be used in the present invention.

  As a diamine to be reacted with bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride forming the structure of formula (1), 1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, 4,4′-diaminodiphenylmethane, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 3,3′-dimethyl-4,4′- Diaminobiphenyl, 2,2′-dimethyl-4,4′-diaminobiphenyl, 4,4′-diaminobenzophenone, 3,3′-diaminobenzophenone, 4,4′-bis (4-aminophenyl) sulfide, 4, 4'-diaminodiphenyl sulfone, 4,4'-diaminobenzanilide, 9,9-bis (4-aminophenyl) fluorene, 1,4-bi (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, 2 , 2-bis (4-aminophenoxyphenyl) propane, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 3,3 '-Dicarboxy-4,4'-diaminodiphenylmethane, 3,3', 5,5'-tetramethyl-4,4'-diaminodiphenylmethane, 3,3 ', 5,5'-tetraethyl-4,4' -Diaminodiphenylmethane, 3,3'-diethyl-5,5'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dihydroxy- , 4′-diaminobiphenyl, hexamethylenediamine, isophoronediamine, bis (4-aminocyclohexyl) methane, methylenebis (2-methyl-4-aminocyclohexyl), 1,3-bis (3-aminopropyl) -1,1 , 3,3-tetramethyldisiloxane, α, ω-bis (3-aminopropyl) polydimethylsiloxane, 2,6-diaminopyridine, 2,4-diamino-6-methyl-1,3,5-triazine, 2,4-diamino-6-phenyl-1,3,5-triazine, 2,4-diamino-6-hydroxypyrimidine, 4,4'-methylenebis (cyclohexylamine), 4,4'-diamino-3,3 '-Dimethyldiphenylmethane, 1,3-bis (3-aminophenoxy) benzene, 6,6-diaminobipyridyl, 5 (6)- - (4'-aminophenyl) -1,3,3-trimethyl indane, and the like.

  The tetracarboxylic dianhydride to be reacted with the diamine or diisocyanate forming the structure of the formulas (2) to (5) is 3,4,3 ′, 4′-biphenyltetracarboxylic dianhydride, 3,4 , 2 ′, 3′-biphenyltetracarboxylic dianhydride, 3,4,3 ′, 4′-diphenyl ether tetracarboxylic dianhydride, 3,4,3 ′, 4′-diphenylsulfonetetracarboxylic dianhydride , Benzophenonetetracarboxylic dianhydride, bis (dicarboxyphenyl) propane anhydride, pyromellitic anhydride, 4,4 ′-(2,2-isopropylidene) diphthalic dianhydride, bicyclo [2,2,2 Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and the like.

  100 mol% of the resin repeating unit in which the formula (1) and the formulas (2) to (5) are combined is one of desirable forms. Moreover, in order to increase the ease of forming the process, it is possible to contain other polyimide structures. Here, the other polyimide structure is a bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride which is an acid dianhydride constituting the formula (1). Other than tetracarboxylic dianhydrides, diaminopyridines, diamino-1,3,5-triazines, diamino-1,3,5-triazine derivatives mentioned as diamines constituting the formulas (2) to (5), It is a structure that can be formed by using a diamine other than diaminodipyridyl, diaminopyrimidine, or a diaminopyrimidine derivative or a diisocyanate derived therefrom. In this case, 40 mol% or more of the repeating unit of the polyimide resin layer is at least one of the structures represented by the above formulas (1) to (5), and is in close contact with the insulating film and conductor layer described below. Is preferable because of its heat resistance and heat resistance.

  Depending on the combination of the aforementioned tetracarboxylic dianhydride and diamine or diisocyanate, the polyimide may be insoluble in the solvent. In such a case, it is coated and dried on a substrate such as an insulating film in the state of polyamic acid which is a polyimide precursor, heated to 150 to 250 ° C. or immersed in a solution containing acetic anhydride and pyridine. The polyimide resin of the present invention can be formed by dehydrating and ring-closing and imidizing.

  To obtain the polyimide resin directly or to obtain the polyimide precursor, a dried polar solvent is used. Examples of the polar solvent include polar solvents that dissolve polyimide, such as N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, dimethylsulfoxide, sulfolane, tetramethylurea, γ-butyrolactone, and m-cresol. It is also possible to use a mixture of ester, ketone or ether solvents, such as methyl benzoate as the ester solvent, methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone as the ketone solvent. , Methyl butyl ketone, methyl isobutyl ketone, methyl-n-hexyl ketone, diethyl ketone, diisopropyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, acetylacetone, diacetone alcohol, cyclohexene-n-one, etc. Solvents include dipropyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran, tetrahydropyran, ethyl isoamyl alcohol, ethyl tert-butyl ether, ethyl benzyl Ether, diethylene glycol dimethyl ether, cresyl methyl ether, anisole, phenetole and the like can be used. At this time, when the polyimide is dissolved in the solvent, an imidization reaction can be performed in the solvent. In order to remove water generated by the imide during the reaction, it is necessary to add a solvent azeotropically with water, such as toluene and xylene, and remove it from the system. In order to accelerate the reaction, an acid catalyst such as p-toluenesulfonic acid and an amine catalyst such as pyridine are preferably used. On the other hand, when polyimide does not dissolve in the solvent, a polyamic acid as a precursor is prepared in the above-described solvent, and applied to a substrate such as an insulating film to form a polyamic acid layer. Thereafter, this layer can be imidized, for example, by heating or dipping in acetic anhydride and pyridine to form the polyimide resin of the present invention.

  Bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride constituting formulas (1) to (5), diaminopyridine, diamino-1,3,5 -Monomers used in addition to triazine, diamino-1,3,5-triazine derivatives, diaminodipyridyl, diaminopyrimidine, and diaminopyrimidine derivatives include the following tetracarboxylic dianhydrides and diamines. Examples of the tetracarboxylic dianhydride include 3,4,3 ′, 4′-biphenyltetracarboxylic dianhydride, 3,4,2 ′, 3′-biphenyltetracarboxylic dianhydride, 3,4,3. ', 4'-diphenyl ether tetracarboxylic dianhydride, 3,4,3', 4'-diphenylsulfone tetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride, bis (dicarboxyphenyl) propane anhydride, Examples include pyromellitic acid and 4,4 ′-(2,2-isopropylidene) diphthalic dianhydride. Examples of the diamine include 1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, 4,4′-diaminodiphenylmethane, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 3, 3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 4,4'-bis (4-aminophenyl) sulfide, 4,4′-diaminodiphenyl sulfone, 4,4′-diaminobenzanilide, 9,9-bis (4-aminophenyl) fluorene, 1,4-bis (4-aminophenoxy) Benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) ) Biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, 2,2-bis (4-aminophenoxyphenyl) propane, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2, − Bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 3,3′-dicarboxy-4,4′-diaminodiphenylmethane, 3,3 ′, 5,5′-tetramethyl-4,4′- Diaminodiphenylmethane, 3,3 ′, 5,5′-tetraethyl-4,4′-diaminodiphenylmethane, 3,3′-diethyl-5,5′-dimethyl-4,4′-diaminodiphenylmethane, 3,3′- Dihydroxy-4,4′-diaminobiphenyl, hexamethylenediamine, isophoronediamine, 1,3-bis (3-aminopropyl) -1, , 3,3-tetramethyldisiloxane, alpha, .omega.-bis (3-aminopropyl) polydimethylsiloxane and the like.

  The polyimide resin having the structure represented by formulas (1) to (5) as a repeating unit preferably has a weight average molecular weight of 50000 or more from the viewpoint of film properties, and preferably has a weight average molecular weight of 300000 or less from the viewpoint of paint viscosity. Moreover, the ratio of the tetracarboxylic dianhydride and diamine used for the molecular weight control does not necessarily need to be equimolar. Further, the resin terminal may be sealed with an acid anhydride such as maleic anhydride or phthalic anhydride, or a monoamine such as aniline.

[Film with conductor]
Next, the conductor-equipped film of the present invention will be described in detail.
Examples of the insulating film used for the conductor-coated film of the present invention include fragrances such as polyethylene terephthalate, polynaphthalene terephthalate, polyphenylene sulfide, polyphenylene ether resin, polyamide resin, and trade name “Aramika” (manufactured by Teijin Advanced Films Ltd.). Non-thermoplastic polyimide series of trade name "Kapton" (manufactured by Toray DuPont Co., Ltd., manufactured by DuPont Co., Ltd.) Non-thermoplastic polyimide series such as Apical (manufactured by Kaneka Corporation), fluororesin such as tetrafluoroethylene resin, fluorinated ethylene propylene copolymer resin, perfluoroalkoxy resin, trade name “BEXTER” ( Any such a liquid crystal polymer is Ltd.) and the like. The thickness of the insulating film is preferably 1 to 200 μm.

  The polyimide resin layer constituting the present invention can be easily formed by coating and drying the polyimide solution in the polyimide resin on the surface of the insulating film. As the coating method, various methods such as reverse roll, rod (bar), blade, knife, comma, die, lip, gravure, and rotary screen are possible. The drying is not particularly limited as long as it can apply a temperature sufficient to remove the solvent to be used, such as a hot air dryer or an infrared dryer. The thickness of the polyimide resin layer is preferably 0.1 to 10 μm. If the thickness is less than 0.1 μm, it is difficult to obtain sufficient adhesion to the conductor layer, while if it exceeds 10 μm, there is a problem in heat resistance and heat resistance during moisture absorption. There may be. A more preferable thickness of the polyimide resin layer is 0.5 to 5 μm.

  Examples of the metal constituting the conductor layer in the present invention include copper, stainless steel, aluminum, nickel, and steel. Among these, copper is preferably used. For the formation of the conductor layer, means such as the above metal foil and plating, sputtering, etc. can be applied to the present invention. Among these, formation by electroless plating and then electrolytic plating on the polyimide resin layer is preferable because of excellent adhesion. In the present invention, any known method can be used for electroless plating and electrolytic plating. The conductor layer may be provided only on one side of the insulating film or may be provided on both sides according to the use of the film with a conductor. When providing a conductor layer on both surfaces of an insulating film, after forming the said polyimide resin layer on both surfaces of an insulating film, what is necessary is just to form a conductor layer.

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.
Synthesis example 1
12.41 g (50 mmol) of bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and 3,4,3 ′, 4′-diphenylsulfonetetracarboxylic 17.91 g (50 mmol) of acid dianhydride, 5.46 g (50 mmol) of 2,6-diaminopyridine and 14.62 g (50 mmol) of 1,3-bis (3-aminophenoxy) benzene were mixed with m-cresol. After dissolving in 250 ml and stirring at 25 ° C. for 1 hour, 50 ml of xylene was added and water azeotroped with xylene was removed while stirring at 180 ° C. for 3 hours to obtain a polyimide solution of the present invention. A part of the solution was added to 10 times the amount of methanol, and the product was washed and dried. When the IR spectrum was measured, absorption peaks peculiar to imides were observed at 1781 and 1722 cm ⁻¹ . The obtained solution was used for coating as it was.

Synthesis example 2
29.42 g (100 mmol) of 3,4,3 ′, 4′-biphenyltetracarboxylic dianhydride and 12.52 g (100 mmol) of 2,4-diamino-6-methyl-1,3,5-triazine Was dissolved in 250 ml of m-cresol, stirred at 25 ° C. for 1 hour, 50 ml of xylene was added, and the water azeotroped with xylene was removed while stirring at 180 ° C. for 3 hours to obtain a polyimide solution of the present invention. It was. A part of the solution was added to 10 times the amount of methanol, the product was washed and dried, and the IR spectrum was measured. As a result, absorption peaks peculiar to imide were observed at 1782 and 1723 cm ⁻¹ . The obtained solution was used for coating as it was.

Synthesis example 3
3,4,3 ′, 4′-benzophenonetetracarboxylic dianhydride 32.22 g (100 mmol), 6,6′-diamino-2,2′-dipyridyl 11.17 g (60 mmol) and 2,2- 16.42 g (40 mmol) of bis [4- (4-aminophenoxy) phenyl] propane was dissolved in 250 ml of m-cresol, stirred for 1 hour at 25 ° C., added with 50 ml of xylene, and stirred for 3 hours at 180 ° C. While the water azeotroped with xylene was removed, the polyimide solution of the present invention was obtained. A part of the solution was added to 10 times the amount of methanol, and the product was washed and dried. When the IR spectrum was measured, absorption peaks peculiar to imide were observed at 1781 and 1723 cm ⁻¹ . The obtained solution was used for coating as it was.

Synthesis example 4
3,4,3 ′, 4′-diphenyl ether tetracarboxylic dianhydride 31.02 g (100 mmol), 2,4-diamino-6-hydroxypyrimidine 10.09 g (80 mmol) and 3,4′-diaminodiphenyl ether 4.00 g (20 mmol) was dissolved in 250 ml of m-cresol, stirred at 25 ° C. for 1 hour, 50 ml of xylene was added, and the water azeotroped with xylene was removed while stirring at 180 ° C. for 3 hours. A polyimide solution of the present invention was obtained. A part of the solution was added to 10 times the amount of methanol, and the product was washed and dried. When the IR spectrum was measured, absorption peaks peculiar to imide were observed at 1780 and 1721 cm ⁻¹ . The obtained solution was used for coating as it was.

Synthesis example 5
7.45 g (30 mmol) of bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and 3,4,3 ′, 4′-diphenylsulfonetetracarboxylic 18.08 g (70 mmol) of acid dianhydride and 29.23 g (100 mmol) of 1,3-bis (3-aminophenoxy) benzene were dissolved in 250 ml of m-cresol, stirred at 25 ° C. for 1 hour, While adding 50 ml of xylene and stirring at 180 ° C. for 3 hours, water azeotroped with xylene was removed to obtain a polyimide solution of the present invention. A part of the solution was added to 10 times the amount of methanol, and the product was washed and dried. When the IR spectrum was measured, absorption peaks peculiar to imide were observed at 1779 and 1721 cm ⁻¹ . The obtained solution was used for coating as it was.

Comparative Synthesis Example 1
35.83 g (100 mmol) of 3,4,3 ′, 4′-diphenylsulfonetetracarboxylic dianhydride and 29.23 g (100 mmol) of 1,3-bis (3-aminophenoxy) benzene were mixed with m-cresol. After dissolving in 250 ml and stirring at 25 ° C. for 1 hour, 50 ml of xylene was added and water azeotroped with xylene was removed while stirring at 180 ° C. for 3 hours to obtain a polyimide solution. A part of the solution was added to 10 times the amount of methanol, and the product was washed and dried. When the IR spectrum was measured, absorption peaks peculiar to imides were observed at 1781 and 1722 cm ⁻¹ . The obtained solution was used for coating as it was.

[Examples 1 to 5 and Comparative Examples 1 and 2]
The polyimide solutions obtained in Synthesis Examples 1 to 5 and Comparative Synthesis Example 1 were prepared as shown in Table 1 to prepare films with conductors of Examples and Comparative Examples. Specifically, a product name: Kapton 150EN (manufactured by Toray DuPont) was applied as an insulating film with a bar coater, and dried at 200 ° C. for 3 hours to form a 3 μm polyimide resin layer. Next, (1) Circposite Conditioner / Neutralizer 3320, (2) Caterpill 404, (3) Cataposit 44, (4) Accelerator 19E, (5) Cueposit Copper Mix 328L (from (1) to (5 ) Were processed in this order using each of the electroless plating chemicals manufactured by Shipley Far East Co.) to form an electroless plating of copper. Further, copper electroplating was formed on the electroless plating to form a conductor layer having a thickness of 9 μm to obtain a film with a conductor for the present invention and a flexible printed wiring board for comparison. The electrolytic plating conditions were a plating bath containing 100 g / liter of CuSO ₄ .5H ₂ O and 150 g / liter of H ₂ SO ₄ , a plating temperature of 25 ° C., and a plating time of 30 minutes.

  Insulating film not provided with a polyimide resin layer, trade name: Kapton 150EN (manufactured by Toray DuPont Co., Ltd.) is subjected to the above-mentioned electroless plating and electrolytic plating steps, and with a conductor for the flexible printed wiring board of Comparative Example 2 A film was obtained.

  The films with conductors of Examples 1 to 5 and Comparative Examples 1 and 2 obtained above were evaluated for adhesion of the conductor layer and moisture-absorbing solder heat resistance, and the results are shown in Table 1. As a result, there is a difference in the normal adhesion strength between the polyimide resin layers of Examples 1 to 5 and Comparative Example 1 (90 degree peel strength of conductor layer using TENENTON universal testing machine manufactured by ORIENTEC, line width of 1 mm, and so on). However, the adhesion strength of the conductor layer after treatment at 150 ° C. for 168 hours or after treatment at 85 ° C. and 85% RH for 168 hours was confirmed to be excellent in the film with conductor of each example. Furthermore, after treating for 168 hours at 85 ° C. and 85% RH, and applying it to a solder bath at 280 ° C. for 60 seconds to confirm the heat resistance of the hygroscopic solder, the appearance was good in Examples 1 to 5 of the present invention. In Example 1, blistering occurred, and in Comparative Example 2, minute foaming occurred, which was confirmed as a practical problem.

Claims (7)

A polyimide resin comprising at least one of structures represented by the following formulas (1) to (5) as a repeating unit.

(Wherein R represents H, CH ₃ , C ₆ H ₅ , OH) In a film with a conductor in which a conductor layer is formed on at least one surface of an insulating film, between the insulating film and the conductor layer, at least one of structures represented by the following formulas (1) to (5) is used as a repeating unit. A conductive film having a polyimide resin layer.

(Wherein R represents H, CH ₃ , C ₆ H ₅ , OH)   The insulating film is one of polyethylene terephthalate, polynaphthalene terephthalate, polyphenylene sulfide, polyphenylene ether resin, polyamide resin, aromatic polyamide resin, polyimide resin, fluorine resin, and liquid crystal polymer, and has a thickness. The film with a conductor according to claim 2, wherein is 1 to 200 μm.   The film with a conductor according to claim 2, wherein the polyimide resin layer has a thickness of 0.1 to 10 μm.   The film with conductor according to claim 2, wherein 40 mol% or more of the repeating unit of the polyimide resin layer is at least one of the structures represented by the formulas (1) to (5).   The film with a conductor according to claim 2, wherein the conductor layer has a thickness of 1 to 20 μm and is formed by electroless plating and electrolytic plating. In a film with a conductor for a flexible printed wiring board in which a conductor layer is formed on at least one surface of an insulating film, at least one of the structures represented by the following formulas (1) to (5) is provided between the insulating film and the conductor layer. A film with a conductor for a flexible printed wiring board, comprising a polyimide resin layer having a seed as a repeating unit.

(Wherein R represents H, CH ₃ , C ₆ H ₅ , OH)