JP2006117957A - Method of manufacturing non-crystalline polyimide film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a polyimide film which is capable of providing a metal foil laminate of an all-polyimide solving the problem that peel strength (adhesion strength) is low, if a metal foil to which surface roughening treatment such as adhesion force accelerating treatment or the like is not applied is used in a conventional known metal foil laminate for a substrate. <P>SOLUTION: The method of manufacturing non-crystalline polyimide film comprises mixing and dissolving organic solvent, 2,2-bis(4-aminophenoxyphenyl)propane and 3,3',4,4'-biphenyltetracarboxylic dianhydride, or each of the derivatives in a reaction container, polymerizing it to obtain a solution of polyamic acid, adding the solution of polyamic acid or a solution of polyamic acid added with the organic solvent, and using it as a dope of polyamic acid, forming a film of dope, removing the solvent by evaporation from the film, and imidizing the polyamic acid. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a method for producing an amorphous polyimide film.
According to this invention, there is provided a metal foil laminate in which the adhesion between a polyimide film and a metal foil such as stainless steel (SUS) which has not been subjected to a special surface treatment such as a surface roughening treatment such as adhesion promotion is improved. Obtainable. In this specification, the non-crystalline polyimide refers to a material in which an X-ray diffraction spectrum is measured by a wide-angle X-ray diffraction method and no peak derived from crystalline scattering is observed.

Conventionally, aromatic polyimide films have been widely used as applications for electronic devices such as cameras, personal computers, and liquid crystal displays. In order to use an aromatic polyimide film as a substrate material such as a flexible printed board (FPC) or tape-automated bonding (TAB), a copper foil is bonded using an adhesive such as an epoxy resin. The method is adopted.

  Aromatic polyimide films are excellent in heat resistance, mechanical strength, electrical characteristics, etc., but it has been pointed out that since the heat resistance of adhesives such as epoxy resins is inferior, the characteristics of the original polyimide are impaired. In order to solve such problems, copper is electroplated on the polyimide film without using an adhesive, or a polyamic acid solution is applied to the copper foil, followed by drying, imidization, or thermocompression bonding of thermoplastic polyimide. An all-polyimide substrate has also been developed.

  Also known is a polyimide laminate in which a film-like polyimide adhesive is sandwiched between a polyimide film and a metal foil, and a method for producing the same (US Pat. No. 4,543,295). However, this polyimide laminate and its manufacturing method have a problem that the metal foil that has not been subjected to surface roughening treatment such as adhesion promotion has a small peel strength (adhesive strength) and its use is restricted.

U.S. Pat. No. 4,543,295

  The object of the present invention is that the peel strength (adhesive strength) is small when a metal foil that has not been subjected to surface roughening treatment such as adhesion promotion described above, which has been conventionally known for metal foil laminates for substrates. An object of the present invention is to provide a method for producing a polyimide film capable of providing a metal foil laminate of solved all polyimide.

That is, the present invention relates to an organic solvent, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride as an aromatic tetracarboxylic acid component or a derivative thereof, and 2, as an aromatic diamine component in a reaction vessel. Each component of 2-bis (4-aminophenoxyphenyl) propane is stirred and dissolved, and then polymerized to form a polyamic acid solution. An organic solvent is further added to the polyamic acid solution or the polyamic acid solution to form a polyamic acid solution. A method for producing an amorphous polyimide film, comprising: forming a thin film of a dope, heating and drying the thin film to evaporate and removing the solvent, and imide cyclization of polyamic acid About.

According to this invention, since it has the above-described configuration, it is possible to obtain a metal foil laminate in which a metal foil that has not been subjected to a special surface treatment and a thermocompression bonding polyimide film are laminated with high peel strength. it can. In addition, according to the method of the present invention, a metal foil laminate in which a metal foil that has not been surface-treated by a simple operation is pretreated and the metal foil and the thermocompression bonding polyimide film are laminated with high peel strength is manufactured. be able to.

The preferred embodiments of the present invention are listed below.
1) Method for producing an amorphous polyimide film in which the polyamic acid dope is 1 to 20% by weight of polyamic acid 2) The ratio of the aromatic tetracarboxylic acid component to the aromatic diamine component is A method for producing the above amorphous polyimide film having an acid excess of 6 mol% to 6 mol%.
3) The method for producing an amorphous polyimide film as described above, wherein the reaction vessel is in a nitrogen atmosphere.
4) The method for producing the above amorphous polyimide film, wherein the organic solvent is N, N-dimethylformamide or N, N-dimethylacetamide.
5) The manufacturing method of said amorphous polyimide film whose amorphous polyimide film is for metal foil laminated bodies.
6) The manufacturing method of said amorphous polyimide film | membrane whose film | membrane is 0.05-3 micrometers in thickness.

  In the said metal foil laminated body, the metal foil of the surface state more than the level which has not performed the roughening process is used. Examples of such a metal foil include a metal foil that has not been subjected to roughening treatment, but may be one that has been subjected to roughening treatment. In particular, in the present invention, SUS (manufactured by Nippon Steel Co., Ltd., SUS304HTAMW) or aluminum foil (manufactured by Nippon Foil Co., Ltd., A1085H-H18) is used as the metal foil having a surface state of a level not higher than the above roughening treatment. If a metal foil not subjected to roughening treatment such as) is used, a remarkable effect is obtained. It is preferable that the surface state metal foil of the level which is not subjected to the roughening treatment has a surface Ra of about 0.2 μm or less and a thickness of about 1 to 500 μm. What is called a metal plate with a large thickness is also included.

  An amorphous polyimide film having a glass transition temperature in the range of 200 to 300 ° C. and a thickness in the range of 0.05 to 3 μm may be formed on a metal foil having a surface state that is not subjected to the roughening treatment. is necessary. By forming a thin layer of non-crystalline polyimide that satisfies the above conditions even if it is a metal foil that has not been roughened, all polyimide that has heat resistance and high peel strength (adhesive strength) A metal foil laminate can be obtained. If a thin layer of crystalline polyimide is formed on a metal foil that has not been subjected to the roughening treatment, the peel strength (adhesive strength) is reduced. Moreover, even if it is an amorphous polyimide, when the glass transition temperature is outside the above range, the heat resistance of the metal foil laminate is insufficient or the peel strength (adhesion strength) is reduced. If the thickness of the amorphous polyimide layer is outside the above range, the peel strength (adhesive strength) of the metal foil laminate may be reduced or the metal foil laminate (especially after etching to form a circuit) may be reduced. -In either case, it is not preferable.

Examples of the amorphous polyimide having a glass transition temperature in the range of 200 to 300 ° C. include 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3 ′. , 4′-biphenyltetracarboxylic dianhydride (a-BPDA), 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether Aromatic tetracarboxylic acid components such as anhydrides and derivatives thereof (acid, acid ester, acid half ester) and 1,3-bis (4-aminophenoxy) benzene (TPE-R), 1,3-bis (3-aminophenoxy) benzene (APB), 2,2-bis (4-aminophenoxyphenyl) propane (BAPP), 4,4′-bis (4-aminophenoxyphenyl) sulfone (BAPS) Can be obtained from a bis (4-aminophenoxy) flexible coupling, such as biphenyl _{[O, C (CH 3)} 2, SO 2] polycyclic aromatic diamine component having. A part of the aromatic tetracarboxylic acid component and the polycyclic aromatic diamine component is mixed with other aromatic tetracarboxylic acid components such as pyromellitic dianhydride and other aromatic diamines such as 4,4′-diaminodiphenyl. It may be replaced with ether. Further, the end of the amorphous polyimide may be sealed with phthalic anhydride or the like.

  In particular, as the non-crystalline polyimide, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and / or its derivative and 2,2-bis (4-aminophenoxyphenyl) propane and / or 1 Polyimide obtained from 1,3-bis (3-aminophenoxy) benzene, obtained from 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride and 1,3-bis (4-aminophenoxy) benzene Polyimide obtained from 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 4,4′-bis (4-aminophenoxyphenyl) sulfone, among which 3,3 ′, 4 , 4′-biphenyltetracarboxylic dianhydride and / or its derivative and 2,2-bis (4-aminophenoxyphenyl) propane The polyimide obtained is suitable from the viewpoint of dope stability, adhesive strength, low water absorption, and hydrolysis resistance. Further, the ratio of the aromatic tetracarboxylic acid component and the aromatic diamine for obtaining the amorphous polyimide may be shifted from an equimolar amount to an excess of acid by about 5 to 6 mol%.

  The non-crystalline polyimide film is prepared by reacting each of the above components in an organic solvent at a temperature of about 100 ° C. or less, particularly 20 to 60 ° C. to obtain a polyamic acid solution. Furthermore, using an organic solvent added to adjust the polyamic acid concentration as a dope, forming a thin film of the above-mentioned dope solution on a metal foil having a surface state at a level not higher than the roughening treatment, 50 It can be formed by heating and drying at ˜400 ° C. for about 1 to 30 minutes to evaporate and remove the solvent from the thin film and cyclize the polyamic acid. The polyamic acid dope that provides the amorphous polyimide preferably has a polyamic acid concentration of about 1 to 20% by weight.

As the thermocompression-bonding polyimide film, a thermocompression-bonding single-layer polyimide film, preferably a thermocompression-bonding multilayer polyimide film having a thermocompression-bonding polyimide layer on at least one surface, preferably both surfaces of the heat-resistant polyimide layer is used. The thermocompression bonding polyimide film has thermocompression bonding and a linear expansion coefficient (50 to 200 ° C.) (MD) of 30 × 10 ⁻⁶ cm / cm / ° C. or less, particularly 15 × 10 ^{−6 to} 25 × 10 ⁻⁶ cm / cm / ° C. And those having a thickness of 10 to 150 μm are preferred, and those having a tensile modulus (MD, ASTM-D882) of 300 kg / mm ² or more are preferred.

  The thermocompression-bonding multilayer polyimide film is preferably formed by laminating a heat-resistant polyimide precursor solution and a thermocompression-bonding polyimide precursor solution by a coextrusion-casting film forming method (also simply referred to as a multilayer extrusion method). Drying and imidizing to obtain a thermocompression-bonding multilayer polyimide film, or applying the above heat-resistant polyimide precursor solution onto a support and applying the thermocompression-bonding polyimide to one or both sides of the dried gel film The precursor solution can be applied, dried and imidized to obtain a thermocompression-bonding multilayer polyimide film.

  The thermocompression bonding polyimide as the thermocompression bonding layer can be selected from various known thermoplastic polyimides, preferably 1,3-bis (4-aminophenoxybenzene) and 2,3,3 ′. , 4'-biphenyltetracarboxylic dianhydride. Moreover, as a thermocompression bonding polyimide as the thermocompression bonding layer, 1,3-bis (4-aminophenoxy) -2,2-dimethylpropane (DANPG) and 4,4′-oxydiphthalic dianhydride (ODPA) And a-BPDA. Alternatively, it is prepared from 4,4'-oxydiphthalic dianhydride (ODPA) and pyromellitic dianhydride and 1,3-bis (4-aminophenoxybenzene).

  The thermocompression bonding polyimide is obtained by reacting each of the above components with another tetracarboxylic dianhydride and another diamine in an organic solvent at a temperature of about 100 ° C. or less, particularly 20 to 60 ° C. To form a polyamic acid solution, use the polyamic acid solution as a dope solution, form a thin film of the dope solution, evaporate and remove the solvent from the thin film, and imide cyclize the polyamic acid. Can be manufactured. In addition, the polyamic acid solution produced as described above is heated to 150 to 250 ° C., or an imidizing agent is added and reacted at a temperature of 150 ° C. or less, particularly 15 to 50 ° C. to imide cyclization. Thereafter, the solvent is evaporated or precipitated in a poor solvent to form a powder, and then the powder is dissolved in an organic solution to obtain an organic solvent solution of a thermocompression bonding polyimide.

  Other tetracarboxylic dianhydrides, for example, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4), as long as the physical properties of the thermocompression bonding polyimide are not impaired. -Dicarboxyphenyl) propane dianhydride or 2,3,6,7-naphthalenetetracarboxylic dianhydride, preferably replaced with 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride May be.

  Further, other diamines such as 4,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, 4,4′-diaminodiphenylmethane, 2,2-bis, as long as the physical properties of the thermocompression bonding polyimide are not impaired. (4-aminophenyl) propane, 1,4-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenyl) diphenyl ether, 4,4′-bis (4-aminophenyl) Diphenylmethane, 4,4′-bis (4-aminophenoxy) diphenyl ether, 4,4′-bis (4-aminophenoxy) diphenylmethane, 2,2-bis [4- (aminophenoxy) phenyl] propane, 2, , Flexible aromatic dia with multiple benzene rings such as 2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane Mine, 1,4-diaminobutane, 1,6-diaminohexane, 1,8-diaminooctane, 1,10-diaminodecane, 1,12-diaminododecane and other aliphatic diamines, bis (3-aminopropyl) tetra It may be replaced by a diaminodisiloxane such as methyldisiloxane. The proportion of other aromatic diamine used is preferably 20 mol% or less, particularly preferably 10 mol% or less, based on the total diamine. Moreover, it is preferable that the usage-amount of aliphatic diamine and diaminodisiloxane is 20 mol% or less with respect to all the diamine. If this ratio is exceeded, the heat resistance of the thermocompression bonding polyimide decreases.

  Dicarboxylic anhydrides, such as phthalic anhydride and its substitutes, hexahydrophthalic anhydride and its substitutes, succinic anhydride and its substitutes, etc., for sealing the amine ends of the thermocompression bonding polyimides, Phthalic anhydride may be used.

  In order to obtain the thermocompression-bondable polyimide, the amount of diamine (as the number of moles of amino group) used in the organic solvent is the total number of moles of acid anhydride (tetraacid dianhydride and dicarboxylic acid anhydride). As a ratio to the total moles as acid anhydride groups), preferably from 0.92 to 1.1, in particular from 0.98 to 1.1, in particular from 0.99 to 1.1. Each component can be reacted in such a ratio that the amount of the product used is preferably 0.05 or less as the ratio of the tetracarboxylic dianhydride to the molar amount of the acid anhydride group.

  If the ratio of the diamine and dicarboxylic acid anhydride is outside the above range, the resulting polyamic acid, and hence the thermocompression bonding polyimide, has a low molecular weight, resulting in a decrease in the adhesive strength of the laminate with the metal foil. In addition, for the purpose of limiting the gelation of polyamic acid, a phosphorus stabilizer such as triphenyl phosphite, triphenyl phosphate is 0.01 to 1% based on the solid content (polymer) concentration during polyamic acid polymerization. Can be added in the range of. An imidizing agent can be added to the dope solution for the purpose of promoting imidization. For example, imidazole, 2-imidazole, 1,2-dimethylimidazole, 2-phenylimidazole, benzimidazole, isoquinoline, substituted pyridine and the like are 0.05 to 10 weights with respect to the polyamic acid. %, Especially 0.1 to 2% by weight. These can complete the imide at relatively low temperatures.

  For the purpose of stabilizing the adhesive strength, an organoaluminum compound, an inorganic aluminum compound, or an organotin compound may be added to the thermocompression bonding polyimide raw material dope. For example, aluminum hydroxide, aluminum triacetylacetonate or the like can be added in an amount of 1 ppm or more, particularly 1 to 1000 ppm as an aluminum metal with respect to the polyamic acid.

  The heat-resistant polyimide as the base layer of the thermocompression-bonding multilayer polyimide film is preferably 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and paraphenylenediamine (hereinafter simply abbreviated as PPD). And optionally 4,4′-diaminodiphenyl ether (hereinafter sometimes abbreviated as DADE). In this case, the PPD / DADE (molar ratio) is preferably 100/0 to 85/15. Further, the heat-resistant polyimide as the base layer is composed of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, pyromellitic dianhydride, paraphenylenediamine, and 4,4′-diaminodiphenyl ether. And manufactured from. The heat-resistant polyimide as the substrate layer is produced from pyromellitic dianhydride, paraphenylenediamine, and 4,4'-diaminodiphenyl ether. In this case, the DADE / PPD (molar ratio) is preferably 90/10 to 10/90. Further, the heat-resistant polyimide as the base layer is composed of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride (BTDA), pyromellitic dianhydride (PMDA), paraphenylenediamine (PPD) and 4 , 4'-diaminodiphenyl ether (DADE). In this case, it is preferable that BTDA in acid dianhydride is 20 to 90 mol%, PMDA is 10 to 80 mol%, PPD in diamine is 30 to 90 mol%, and DADE is 10 to 70 mol%.

In addition, as the heat-resistant polyimide as the base layer, it is preferable that the glass transition temperature is 350 ° C. or higher in the case of a single polyimide film, and in particular, the linear expansion coefficient (50 to 200 ° C.) (MD ) are those preferably ^{5x10 -6 ~30x10 -6 cm / cm /} ℃. The tensile modulus (MD, ASTM-D882) is preferably 300 kg / mm ² or more. The synthesis of the base layer polyimide is performed by random polymerization, block polymerization, or by synthesizing two types of polyamic acids in advance and mixing both polyamic acid solutions if the proportion of each component is within the above range. To achieve a homogeneous solution.

  Using each of the above-mentioned components, a substantially equimolar amount of a diamine component and a tetracarboxylic dianhydride are reacted in an organic solvent to give a polyamic acid solution (partly imidized if a uniform solution state is maintained) May be used). Other aromatic tetracarboxylic dianhydrides and aromatic diamines such as 4,4'-diaminodiphenylmethane, etc., which do not impair the physical properties of the base layer polyimide, may be used.

  The organic solvent used for the production of the polyamic acid is N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N for any of amorphous polyimide, thermocompression bonding polyimide and heat resistant polyimide. -Dimethylacetamide, N, N-diethylacetamide, dimethylsulfoxide, hexamethylphosphoramide, N-methylcaprolactam, cresols and the like. These organic solvents may be used alone or in combination of two or more.

  In the production of the thermocompression-bonding multilayer polyimide film, for example, a polyamic acid solution of the heat-resistant polyimide for the base layer and a thermocompression-bonding polyimide for the thermocompression-bonding layer or a precursor solution thereof are coextruded, and this is made of stainless steel. It is preferable to cast and apply on a support surface such as a mirror surface or a belt surface to be in a semi-cured state or a dried state before 100 to 200 ° C. When a cast film is processed at a high temperature exceeding 200 ° C., defects such as a decrease in adhesion tend to be caused in the production of a multilayer polyimide film. This semi-cured state or an earlier state means that it is in a self-supporting state by heating and / or chemical imidization.

  The coextrusion of the polyamic acid solution for providing the base layer polyimide and the polyamic acid solution for providing the thermocompression bonding polyimide is, for example, described in JP-A-3-180343 (JP-B-7-102661). It can supply to the die | dye for extrusion molding of three layers by an extrusion method, and can cast and cast on a support body. A glass transition temperature of the thermocompression bonding polyimide is formed by laminating a polyamic acid solution or a polyimide solution that gives thermocompression bonding polyimide on both sides of the extrudate layer that gives the base layer polyimide, and forming a multi-layer film-like product and drying. (Tg) is heated to a temperature not higher than the temperature at which deterioration occurs, preferably 250 to 420 ° C. (surface temperature measured with a surface thermometer) (preferably heated at this temperature for 1 to 60 minutes) ) Drying and imidization can produce a thermocompression-bonding multilayer extruded polyimide film having thermocompression-bonding polyimide on both sides of the substrate layer polyimide.

  The thermocompression bonding polyimide preferably has a glass transition temperature of 190 to 280 ° C., particularly 200 to 275 ° C. by using the acid component and the diamine component. It is achieved by drying and imidization so as not to cause gelation of thermocompression-bonding polyimide substantially, and does not melt at a temperature within the range of the glass transition temperature to 300 ° C. and elastic modulus (usually 275 ° C. It is preferable that the elastic modulus at is maintained at about 0.001 to 0.5 times the elastic modulus at 50 ° C.

  In the thermocompression-bonding multilayer polyimide film, the base layer polyimide film (layer) preferably has a thickness of 5 to 125 μm, and the thermocompression-bonding polyimide (Y) layer has a thickness of 1 to 25 μm, particularly 1 to 15 μm, among which 2 to 12 μm is particularly preferable. Moreover, it is preferable that the thickness of the thermocompression-bondable polyimide (Y) layer when laminated with the other metal foil is not less than the surface roughness (Rz) of the other metal foil to be used.

  Examples of other metal foils used in the laminate include various metal foils such as copper, aluminum, gold, and alloy foils. Preferred examples include rolled copper foils and electrolytic copper foils. A metal foil having a surface roughness Rz of 0.5 μm or more is preferable. Further, it is preferable that the surface roughness Rz of the metal foil is 10 μm or less, particularly 7 μm or less. Such metal foils, such as copper foils, are known as VLP, LP (or HTE). Although the thickness of metal foil does not have a restriction | limiting in particular, What is 5-60 micrometers, Especially 5-20 micrometers is preferable.

After forming a non-crystalline polyimide film on a metal foil having a surface state of the level not subjected to the above roughening treatment, a thermocompression bonding polyimide film, preferably a thermocompression bonding multi-layer polyimide film is overlaid and continuously pressed. The temperature of the pressurizing part is 30 ° C. or higher and 420 ° C. or lower than the glass transition temperature of the thermocompression bonding polyimide through the member. A metal foil laminate can be produced by thermocompression bonding at cm ² . In the above method, a metal foil laminate having a metal foil on both sides can be obtained by thermocompression bonding a metal foil having an amorphous polyimide thin layer and another metal foil with a thermocompression bonding polyimide film. Also, in the above method, the metal foil on which the amorphous polyimide thin layer is formed and the thermocompression-bondable polyimide film having the two-layer structure of thermocompression-bondable polyimide and heat-resistant polyimide are thermocompression-bonded, and the metal foil is disposed on the other surface. A metal foil laminate having a heat-resistant polyimide layer can be obtained.

  Examples of the continuous pressure member include a pair of pressure-bonded metal rolls (the pressure-bonding part may be made of metal or ceramic sprayed metal) or a double belt press, and particularly capable of thermocompression bonding and cooling under pressure. Thus, a hydraulic double belt press can be mentioned.

  According to the present invention, a metal foil laminate having a high adhesive strength can be produced by a simple treatment. Moreover, the metal foil laminated body obtained by this invention can be used conveniently as a member for electronic components.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. In each of the following examples, the physical property evaluation and the peel strength of the metal foil laminate were measured according to the following methods.
Glass transition temperature: measured by DSC.
Crystallinity: measured by XRD (X-ray diffraction). When no peak was observed, it was evaluated as non-crystalline.
Linear expansion coefficient: measured (MD) at a heating rate of 20 to 200 ° C. and 5 ° C./min.
Peel strength of laminate: 90 degree peel strength was measured.
Heat resistance: The metal foil laminate was immersed in a solder bath at 260 ° C. for 1 minute, and the presence or absence of swelling, peeling or discoloration was observed.

Reference example (manufacture of thermocompression-bonding three-layer extruded polyimide film)
Synthesis of dough for thermocompression bonding polyimide production-1
N, N-dimethylacetamide (DMAc) is added to a reaction vessel equipped with a stirrer and a nitrogen introduction tube, and 1,3-bis (4-aminophenoxy) benzene (TPE-R) and 2,3,3 are further added. ', 4'-biphenyltetracarboxylic dianhydride (a-BPDA) was added at a molar ratio of 1000: 1000 to a monomer concentration of 22%, and triphenyl phosphate was added to the monomer weight. 0.1% was added. After completion of the addition, the reaction was continued for 1 hour while maintaining 25 ° C. The solution viscosity at 25 ° C. was about 2000 poise. This solution was used as a dope.

Synthesis of heat-resistant polyimide manufacturing dope-1
N, N-dimethylacetamide is added to a reaction vessel equipped with an introduction tube, and further, paraphenylenediamine (PPD), 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA), and Was added at a molar ratio of 1000: 998 so that the monomer concentration was 18% (wt%, the same applies hereinafter). After completion of the addition, the reaction was continued for 3 hours while maintaining 50 ° C. The obtained polyamic acid solution was a brown viscous liquid, and the solution viscosity at 25 ° C. was about 1500 poise. This solution was used as a dope.

Manufacture of thermocompression-bonding three-layer extrusion polyimide film Manufacture of the above-mentioned thermocompression-bonding polyimide manufacturing dope and base layer polyimide manufacturing dope with a three-layer extrusion forming die (multi-manifold die) Using a membrane apparatus, the film was cast from a three-layer extrusion die onto a metal support and continuously dried with hot air at 140 ° C. to form a solidified film. After the solidified film is peeled off from the support, the temperature is gradually raised from 200 ° C. to 320 ° C. in a heating furnace to remove the solvent and imidize, and wind a long three-layer extruded polyimide film on a winding roll. I took it. The obtained thermocompression-bonding three-layer extruded polyimide film has a thickness of each layer of 4 μm / 17 μm / 4 μm, a linear expansion coefficient (50-200 ° C.) of MD: 23 ppm / ° C., TD: 19 ppm / ° C., average: It is 21 ppm / ° C., the tensile modulus is 526 kg / mm ² , and the glass transition temperature of the base layer polyimide is not confirmed at a temperature of 400 ° C. or less, and the thermocompression bonding layer polyimide has a glass transition temperature of 250 ° C. and 275 ° C. The elastic modulus at 50 ° C. was 0.002 times the elastic modulus at 50 ° C., and gelation did not substantially occur.

32.84 g (0.08 mol) of 2,2-bis (4-aminophenoxyphenyl) propane (BAPP) and 224.8 g of N, N-dimethylacetamide were stirred and dissolved in a reaction vessel under a nitrogen atmosphere at room temperature. . To this, 23.31 g (0.079 mol) of s-BPDA was gradually added and stirred at 40 ° C. for 3 hours. Thereafter, 2.12 g (0.0058 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic acid dihydrate (s-BPTA) was added and dissolved at room temperature. 10 g of the obtained polyamic acid solution was taken and diluted with 30 g of DMAc to obtain a 5% solution. This varnish (aromatic tetracarboxylic acid component / aromatic diamine is 1.06) is used as a SUS having a thickness of 20 μm (manufactured by Nippon Steel Corporation, SUS304HTAMW, Ra: 0.05 μm, hereinafter simply abbreviated as SUS). And heated to 120 ° C. × 2 minutes, 150 ° C. × 2 minutes, 180 ° C. × 2 minutes, 250 ° C. × 2 minutes to form a polyimide film having a thickness of 0.5 μm. This polyimide was amorphous and had a glass transition temperature (Tg) of 245 ° C. SUS on which the obtained amorphous polyimide was formed, thermocompression-bonding three-layer extruded polyimide film, 18 μm-thick rolled copper foil (Japan Energy BHY foil, Ra: 0.18 μm, hereinafter simply referred to as rolled copper foil) In this order, the laminate was press-bonded at 320 ° C. and 50 kgf / cm ² for 1 minute to obtain a double-sided metal laminate. The 90 ° peel strength of the SUS-polyimide interface of this double-sided metal laminate was 1.90 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

A double-sided metal laminate was obtained in the same manner as in Example 1 except that the thickness of the amorphous polyimide film was 0.20 μm. The 90 ° peel strength of the SUS-polyimide interface of this double-sided metal laminate was 1.90 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

A varnish (aromatic tetracarboxylic acid component / aromatic diamine was 1.040) was obtained in the same manner as in Example 3 except that 0.36 g (0.00098 mol) of s-BPTA was added, and this varnish was used as a dope. Except having used, it implemented similarly to Example 3 and obtained the double-sided metal laminated board which used the amorphous polyimide film. The 90 ° peel strength of the SUS-polyimide interface of this double-sided metal laminate was 1.50 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

A varnish (aromatic tetracarboxylic acid component / aromatic diamine: 0.958) was obtained in the same manner as in Example 3 except that s-BPTA was not added, and Example 3 was used except that this varnish was used as a dope. In the same manner as described above, a double-sided metal laminate using an amorphous polyimide film was obtained. The 90 ° peel strength of the SUS-polyimide interface of this double-sided metal laminate was 1.25 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

The heat treatment conditions for forming the amorphous polyimide thin layer were carried out except that a polyimide film having a thickness of 0.5 μm was formed by heating at 120 ° C. × 2 minutes, 150 ° C. × 2 minutes, 180 ° C. × 2 minutes, 350 ° C. × 2 minutes. In the same manner as in Example 1, a double-sided metal laminate was obtained. The 90 ° peel strength of the SUS-polyimide interface of this double-sided metal laminate was 1.90 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

17.54 g (0.0600 mol) of TPE-R and 124.80 g of DMAc were stirred and dissolved in a reaction vessel at room temperature under a nitrogen atmosphere. To this, 17.83 g (0.0606 mol) of a-BPDA was gradually added and stirred at 40 ° C. for 3 hours. The obtained polyamic acid solution was diluted with DMAc to obtain a 5% solution. A polyimide film was formed in the same manner as in Example 1 except that this varnish (aromatic tetracarboxylic acid component / aromatic diamine was 1.01) was used as a dope. This polyimide was amorphous and had a glass transition temperature (Tg) of 252 ° C. Except having used the obtained amorphous polyimide formation SUS, it implemented similarly to Example 1 and obtained the double-sided metal laminated board. The 90 ° peel strength of the SUS-polyimide interface of this double-sided metal laminate was 0.90 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

BAPP 7.39 g (0.018 mol), APB 0.58 g (0.002 mol), and DMAc 55.40 g were stirred and dissolved in a reaction vessel at room temperature under a nitrogen atmosphere. To this, 5.83 g (0.0198 mol) of s-BPDA was gradually added and stirred at 40 ° C. for 3 hours. The obtained polyamic acid solution was diluted with DMAc to obtain a 5% solution. An amorphous polyimide film was formed on SUS in the same manner as in Example 1 except that this varnish (aromatic tetracarboxylic acid component / aromatic diamine was 0.99) was used as a dope. This polyimide was amorphous and had a glass transition temperature (Tg) of 241 ° C. Except having used the obtained amorphous polyimide formation SUS, it implemented similarly to Example 1 and obtained the double-sided metal laminated board. The 90 degree peel strength of the SUS-polyimide interface of this double-sided metal laminate was 1.55 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

3.28 g (0.008 mol) of BAPP, 0.58 g (0.002 mol) of APB, and 27.20 g of DMAc were stirred and dissolved in a reaction vessel at room temperature in a nitrogen atmosphere. To this, 3.00 g (0.0102 mol) of s-BPDA was gradually added and stirred at 40 ° C. for 3 hours. The obtained polyamic acid solution was diluted with DMAc to obtain a 5% solution. An amorphous polyimide film was formed on SUS in the same manner as in Example 1 except that this varnish (aromatic tetracarboxylic acid component / aromatic diamine was 1.02) was used as a dope. This polyimide was amorphous and had a glass transition temperature (Tg) of 239 ° C. Except having used the obtained amorphous polyimide formation SUS, it implemented similarly to Example 1 and obtained the double-sided metal laminated board. The 90 degree peel strength of the SUS-polyimide interface of this double-sided metal laminate was 2.30 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

BAPS-M: 4.32 g (0.01 mol) of bis [4- (3-aminophenoxy) phenyl] sulfone and 29.04 g of DMAc were stirred and dissolved in a reaction vessel at room temperature under a nitrogen atmosphere. To this, 3.00 g (0.0102 mol) of s-BPDA was gradually added and stirred at 40 ° C. for 3 hours. The obtained polyamic acid solution was diluted with DMAc to obtain a 5% solution. An amorphous polyimide film was formed on SUS in the same manner as in Example 1 except that this varnish (aromatic tetracarboxylic acid component / aromatic diamine was 1.02) was used as a dope. This polyimide was amorphous and had a glass transition temperature (Tg) of 245 ° C. Except having used the obtained amorphous polyimide formation SUS, it implemented similarly to Example 1 and obtained the double-sided metal laminated board. The 90 ° peel strength of the SUS-polyimide interface of this double-sided metal laminate was 1.50 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

1.46 g (0.005 mol) of APB and 11.72 g of DMAc were stirred and dissolved in a reaction vessel under a nitrogen atmosphere at room temperature. To this, 1.50 g (0.0051 mol) of s-BPDA was gradually added and stirred at 40 ° C. for 3 hours. The obtained polyamic acid solution was diluted with DMAc to obtain a 5% solution. An amorphous polyimide film was formed on SUS in the same manner as in Example 1 except that this varnish (aromatic tetracarboxylic acid component / aromatic diamine was 1.02) was used as a dope. This polyimide was amorphous and had a glass transition temperature (Tg) of 206 ° C. Except having used the obtained amorphous polyimide formation SUS, it implemented similarly to Example 1 and obtained the double-sided metal laminated board. The 90 degree peel strength of the SUS-polyimide interface of this double-sided metal laminate was 2.05 kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

A double-sided metal laminate was obtained in the same manner as in Example 1 except that SUS was replaced with 40 μm-thick rolled aluminum foil (A1085H-H18, manufactured by Nippon Foil Co., Ltd.). The 90-degree peel strength at the Al-polyimide interface of this double-sided metal laminate was 1.25 Kgf / cm. Furthermore, even when this double-sided metal laminate was immersed in a solder bath at 260 ° C. for 1 minute, no changes such as swelling, peeling, and discoloration were observed.

Comparative Example 1
2.00 g (0.01 mol) of 4,4′-diaminodiphenyl ether and 19.76 g of DMAc were stirred and dissolved in a reaction vessel at room temperature under a nitrogen atmosphere. To this, 3.00 g (0.0102 mol) of a-BPDA was gradually added and stirred at 40 ° C. for 3 hours. The obtained polyamic acid solution was diluted with DMAc to obtain a 5% solution. A polyimide film was formed on SUS in the same manner as in Example 1 except that this varnish (aromatic tetracarboxylic acid component / aromatic diamine was 1.02) was used as a dope. This polyimide was amorphous and had a glass transition temperature (Tg) of 325 ° C. Except having used the obtained amorphous polyimide formation SUS, it implemented similarly to Example 1 and obtained the double-sided metal laminated board. The 90 degree peel strength of the SUS-polyimide interface of this double-sided metal laminate was 0.20 Kgf / cm.

Comparative Example 2
17.54 g (0.0600 mol) of TPE-R and 124.80 g of DMAc were stirred and dissolved in a reaction vessel at room temperature under a nitrogen atmosphere. To this was gradually added 18.01 g (0.0612 mol) of s-BPDA, and the mixture was stirred at room temperature for 3 hours. A part of the obtained polyamic acid solution was taken out and diluted with DMAc to obtain a 5% solution. A polyimide film was formed on SUS in the same manner as in Example 1 except that this varnish (aromatic tetracarboxylic acid component / aromatic diamine was 1.02) was used as a dope. This polyimide was crystalline and had a glass transition temperature (Tg) of 234 ° C. Except having used the obtained crystalline polyimide formation SUS, it implemented similarly to Example 1 and obtained the double-sided metal laminated board. The 90 ° peel strength of the SUS-polyimide interface of this double-sided metal laminate was 0.10 Kgf / cm.

Comparative Example 3
A double-sided metal laminate was obtained in the same manner as in Example 1 except that SUS not forming amorphous polyimide was used. The 90 degree peel strength of the SUS-polyimide interface of this double-sided metal laminate was 0.50 Kgf / cm. The 90 degree peel strength at the rolled copper foil-polyimide interface of the double-sided metal laminate was 1.5 Kgf / cm in both Examples and Comparative Examples.

Claims (7)

In a reaction vessel, an organic solvent, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride or its derivative as an aromatic tetracarboxylic acid component, and 2,2-bis (4- After stirring and dissolving each component of aminophenoxyphenyl) propane, it is polymerized to form a polyamic acid solution, and an organic solvent is further added to this polyamic acid solution or polyamic acid solution to be used as a polyamic acid dope. A method for producing an amorphous polyimide film, comprising: forming a thin film of a dope, heating and drying the thin film to evaporate the solvent, and imide-cyclizing the polyamic acid. The method for producing an amorphous polyimide film according to claim 1, wherein the polyamic acid dope has a polyamic acid concentration of 1 to 20 wt%. The method for producing an amorphous polyimide film according to claim 1, wherein the ratio of the aromatic tetracarboxylic acid component and the aromatic diamine component is an acid excess of equimolar to 6 mol%. The method for producing an amorphous polyimide film according to claim 1, wherein the reaction vessel is in a nitrogen atmosphere. The method for producing an amorphous polyimide film according to claim 1, wherein the organic solvent is N, N-dimethylformamide or N, N-dimethylacetamide. The method for producing an amorphous polyimide film according to claim 1, wherein the amorphous polyimide film is for a metal foil laminate. The method for producing an amorphous polyimide film according to claim 1, wherein the amorphous polyimide film has a thickness of 0.05 to 3 μm.