CN100562427C

CN100562427C - Bonding film and application thereof

Info

Publication number: CN100562427C
Application number: CNB2005800254238A
Authority: CN
Inventors: 柳田正美; 金城永泰
Original assignee: Kaneka Corp
Current assignee: Kaneka Corp; Kanegafuchi Chemical Industry Co Ltd
Priority date: 2004-07-27
Filing date: 2005-07-20
Publication date: 2009-11-25
Anticipated expiration: 2025-07-20
Also published as: CN1989008A

Abstract

The purpose of this invention is to provide a kind of bonding film, the flexible metal-clad laminate both that can be inhibited by its generation that can obtain change in size when adopting cast coating to make.Bonding film of the present invention possesses the refractory layer that contains the high-fire resistance polyimides and is formed at least one lip-deep adhesive linkage that contains TPI of this refractory layer, and the percent thermal shrinkage on the TD direction is more than+0.01%, and the percent thermal shrinkage on the MD direction is below-0.02%.Thus, metal level and bonding film are carried out when laminated, handle, also can fully suppress the generation of change in size even this lamilated body is applied the processing that has heating by cast coating.

Description

Bonding film and application thereof

Technical field

The present invention relates to have the bonding film and the representative applications thereof of the layer that contains polyimides, particularly relate at least one surface by the layer that constitutes at the high-fire resistance polyimides, the adhesive linkage that formation contains TPI obtains, is suitable for making the bonding film of FPC, the manufacture method of this bonding film and use the lamilated body of this bonding film and FPC etc.

Background technology

In recent years, along with lightweight, miniaturization, the densification of electronic products, to the demand of various printed base plates in continuous expansion.In these printed base plates, especially remarkable to the expansion of FPC demand.FPC is also referred to as flexible print circuit board (FPC) etc.FPC has the structure that forms the circuit that is made of metal level on dielectric film.

Above-mentioned FPC is a substrate with the dielectric film with flexibility that various insulating materials form usually, by by various adhesives, the metal forming heat pressure adhesive is made at the applying method of this substrate surface.As above-mentioned dielectric film, preferably use polyimide film etc., as above-mentioned adhesives, use heat-curable adhesives such as epoxies, acrylic compounds usually.Because the FPC that uses this heat-curable adhesive to form has the three-decker of substrate/adhesives/metal forming, below convenience in order to illustrate, be referred to as " three layers of FPC ".

The heat-curable adhesive that uses among above-mentioned three layers of FPC has can bonding at a lower temperature advantage.But the requirement for the various characteristics of the hear resistance of FPC, bendability, electric reliability and so on after can inferring can become harsh, and as three layers of FPC that use heat-curable adhesive, is commonly considered as being difficult to satisfying this requirement.

To this, proposed on dielectric film, directly to be provided with the FPC of metal level, and the scheme of on adhesive linkage, using the FPC of TPI.Because these FPCs have the state that directly forms metal level on insulated substrate, therefore, for convenience of explanation, hereinafter referred to as " two layers of FPC ".These two layers of FPC have the characteristic than three layers of FPC excellence, can fully satisfy the requirement to above-mentioned various characteristics, and therefore later demand is expected to the meeting sustainable growth.

Above-mentioned two layers of FPC are to use flexible metal-clad laminate both with structure of laminated metal forming on substrate to make.As the manufacture method of this flexible metal-clad laminate both, can enumerate casting method, metalikon, laminating etc.Casting method be with as the polyamic acid of polyimide precursor after curtain coating, coating on the metal forming, carry out the method for imidizate.Metalikon is the method that metal level directly is set on polyimide film by sputter, plating.Laminating is will the method that bonding film that thermoplastic polyimide layer forms and metal forming are fitted be set at least one surface of high-fire resistance polyimide layer.

Wherein, there is following advantage in laminating, that is, the thickness range of metal forming applicatory is more extensive than casting method, and equipment cost is lower than metalikon.As the equipment of implementing laminating, Yi Bian can use hot-roll lamination equipment or the double belt press that weblike material is launched to carry out continuous laminating on one side.In these equipment,, especially preferably use cast coating from aspects such as productivity ratio height, original equipment small investments.

During with in the past three layers of FPC of laminating manufacturing,, can be set to carry out lamination treatment (patent documentation 1) by laminating temperature less than 200 ℃ owing to use thermosetting resin in the adhesive linkage.Relative therewith, because two layers of FPC use TPI as adhesive linkage, therefore, must apply more than 200 ℃ in order to realize hot melt knot property, apply high temperature according to circumstances near 400 ℃.

Here, as cast coating, owing to being that one side presses together metal forming and bonding film by a pair of beaming roller,, on bonding film, apply the stress that makes vertically (following is " MD direction ") to stretch, make laterally (following is " TD direction ") to compress Yi Bian carry.This stress can cause residual deformation, when forming circuit by etching, and change in size can occur when carrying out remelting scolding tin for assembling parts.Specifically, when carrying out hot-roll lamination, tensile force works on the MD direction, and compression stress works on the TD direction.As a result, etching metal paper tinsel from FPC and carry out remelting scolding tin and when heating this strain be released, the MD direction shrinks, and the TD direction expands.

In recent years, for the miniaturization, the lightweight that reach electronic equipment, the circuit that is arranged on the substrate is tending towards miniaturization, also will carry the parts of miniaturization, densification as assembling parts.Therefore,, then can be offset from the component mounting position of design phase if the change in size that forms behind the fine circuit is big, thus the problem that causes parts and substrate well not to be connected.

Therefore, as the technology that suppresses above-mentioned change in size, proposed (1) and the process conditions of lamination treatment has been set at the technology of optimum condition and (2) percent thermal shrinkage of polyimide film is defined in technology in the preferred range.

As the technology of setting above-mentioned process conditions, for example can enumerate, the technology of the pressure as patent documentation 3 described settings when hot-forming, or as the technology of the tension force of the bonding film of patent documentation 2 described settings etc.In addition, technology as the afore mentioned rules percent thermal shrinkage, can enumerate, as described in patent documentation 4, the banded film that regulation is made of aromatic polyimide in the technology of the higher limit of the percent thermal shrinkage under the predetermined condition, regulation hot pressing polyimide film in the technology of the higher limit of the lower limit of the technology of the higher limit of the percent thermal shrinkage 300 ℃ under, regulation Young's modulus and the percent thermal shrinkage under 300 ℃ times and 450 ℃ etc.

[patent documentation 1]

The flat 9-199830 communique of Japanese Patent Application Publication (putting down into 9 years (1997) July 31 openly)

[patent documentation 2]

Japanese Patent Application Publication 2002-326280 communique (putting down into 14 years (2002) November 12 openly)

[patent documentation 3]

Japanese Patent Application Publication 2002-326308 communique (putting down into 14 years (2002) November 12 openly)

[patent documentation 4]

The flat 10-77353 communique of Japanese Patent Application Publication (putting down into 10 years (1998) March 24 openly)

[patent documentation 5]

Japanese Patent Application Publication 2001-270034 communique (putting down into 13 years (2001) October 2 openly)

[patent documentation 6]

Japanese Patent Application Publication 2003-335874 communique (putting down into 15 years (2003) November 28 openly)

But, all there is following problem in above-mentioned conventional art, that is, and and for handle the FPC that forms by hot-roll lamination, therefore the situation that does not shrink when considering etching or on when heating MD direction, expands on the TD direction also exists weak point in practicality.

Specifically, for example, patent documentation 2 and patent documentation 3 disclosed technique treats purposes can substantially improve the change in size of bonding film.But,, can not fully satisfy the fast compactization and the densification of needed electronic device in recent years sometimes owing to do not consider the contraction on the MD direction, the expansion on the TD direction.

On the other hand, patent documentation 4 disclosed technology are being prerequisite by bonding aromatic polyimide film of bonding agent and Copper Foil, patent documentation 5 disclosed technology also are with at least one face of high-fire resistance aromatic polyimide layer, and forming hot pressing aromatic polyimide layer on preferred two faces is prerequisite.That is to say that these technology are the technology that are applicable to three layers of FPC, be not suitable for two layers of FPC.In addition, it is preferred that patent documentation 6 disclosed technology are not specifically addressed any for two layers of FPC or three layers of FPC, the problem when also not being specifically related to hot-roll lamination.

Therefore, the same with disclosed technology in the above-mentioned patent documentation 1～2, disclosed technology is not considered the contraction on the above-mentioned MD direction, the expansion on the TD direction yet in these patent documentations 4～6, thereby has sometimes and can not fully satisfy the fast compactization and the densification of needed electronic device in recent years.

Summary of the invention

The present invention makes in view of above problem, provide and to be suitable for making FPC, and can suppress undertaken variously adding the bonding film that change in size takes place man-hour, an and example that utilizes it by the flexible metal-clad laminate both of hot-roll lamination manufactured.

The inventor furthers investigate the problems referred to above, found that, by controlling the percent thermal shrinkage of bonding film, the bonding film of the flexible metal-clad laminate both that change in size is inhibited in the time of can obtaining to provide by the hot-roll lamination manufactured, thus finished the present invention.Found that particularly the contraction on the bonding film MD direction, the expansion on the TD direction are considered, by two kinds of percent thermal shrinkages on TD direction and the MD direction are defined in the preferred range, can suppress the generation of change in size preferably, thereby finish the present invention.

That is to say, in order to address the above problem, above-mentioned bonding film of the present invention is characterised in that at least one the lip-deep adhesive linkage that contains TPI that possesses the refractory layer that contains the high-fire resistance polyimides and be positioned at this refractory layer, and the percent thermal shrinkage on the TD direction is more than+0.01%, and the percent thermal shrinkage on the MD direction is below-0.02%.

Above-mentioned bonding film forms at least one surface of above-mentioned refractory layer by coextrusion-curtain coating rubbing method preferably that above-mentioned adhesive linkage obtains.In addition, above-mentioned bonding film also can be to form above-mentioned adhesive linkage by the gel coating method at least one surface of above-mentioned refractory layer to obtain.

As above-mentioned bonding film, more preferably the percent thermal shrinkage on the TD direction is more than+0.03%, and the percent thermal shrinkage on the MD direction is below-0.05%.In addition, preferred above-mentioned adhesive linkage is formed on two faces of above-mentioned refractory layer.And, contain the above non-thermal plasticity polyimide resin of 90 weight % in the preferred above-mentioned refractory layer as the high-fire resistance polyimides.In addition, the tensile modulus of elasticity of preferred TD direction and MD direction is in the scope of 5.0～11GPa.

The present invention comprises the lamilated body that uses above-mentioned bonding film to make, and specifically, comprises the lamilated body that forms by in bonding film surface laminated metal forming, for example, can enumerate flexible metal-clad laminate both.In addition, the present invention also comprises the FPC that uses above-mentioned bonding film or above-mentioned lamilated body to form.

And the present invention also comprises the manufacture method of above-mentioned bonding film.Specifically, can enumerate following method, this method comprises: will contain as the organic solvent solution of the polyamic acid of high-fire resistance polyimide precursor and, contain the organic solvent solution of TPI or contain organic solvent solution as the polyamic acid of TPI precursor and be provided to simultaneously and have in the two-layer above extrusion shaping machine of extrusion molding with mouthful mould, the operation that makes above-mentioned two kinds of organic solvent solutions form double-layer films shape material at least and extrude from the outlet of above-mentioned mouthful of mould, extrusion molding more than two-layer is expressed on the level and smooth support continuously with above-mentioned two kinds of organic solvent solutions of extruding mouthful mould, make at least a portion volatilization of the organic solvent of the membranaceous material of two layers of thin at least on the above-mentioned support then, obtain having self-supporting laminate film operation and the TD direction two ends of the laminate film that obtained are fixed, on one side stretch along the TD direction with the extension ratio that surpasses 1.0 times and to carry out the operation of imidizate on one side.

In addition, the manufacture method of above-mentioned bonding film also can be following method, comprising: form operation thereby make the organic solvent solution that contains as the polyamic acid of high-fire resistance polyimide precursor form the membranaceous gel mould of making gel mould, coating contains the organic solvent solution of TPI or contains as the organic solvent solution of the polyamic acid of TPI precursor and the laminated operation that heats at least one surface of the gel mould that is obtained, fix with the TD direction two ends of the laminate film that will be obtained, with the extension ratio that surpass 1.0 times along TD direction stretch and on one side carry out the stretching imidizate operation of imidizate on one side.

In addition, the present invention also comprises the manufacture method of the FPC that uses above-mentioned bonding film or the formation of above-mentioned lamilated body.Specifically, can enumerate by cast coating metal foil layer is pressed in manufacture method on the bonding film.

The specific embodiment

If an embodiment of the invention are described, be following content then, but the present invention is not limited thereto, also comprise the situation that the form that can impose all distortion in above-mentioned scope is implemented.

(I) bonding film

As bonding film of the present invention, even exist various treatment process with heating, also can prevent change in size preferably, it has the laminated structure that contains the adhesive linkage of TPI and form on the surface of the refractory layer that contains the high-fire resistance polyimides.As a whole the time, the percent thermal shrinkage on the transverse direction (TD direction) is more than+0.01% with bonding film, and the percent thermal shrinkage on the longitudinal direction (MD direction) is below-0.02%.

(I-1) refractory layer and use therein high-fire resistance polyimides

＜refractory layer 〉

The refractory layer that bonding film of the present invention possessed contains polyimides, so long as in the operation of using this bonding film to process or with the form of end article under the common residing temperature, the layer that is not easy to take place thermal deformation gets final product, there is no particular limitation for the concrete kind of employed polyimides, but preferably contain the high-fire resistance polyimides.Also have, high-fire resistance is meant, this polyimides is shaped under the membranaceous situation, when being heated in the temperature range about 450～500 ℃, fusion taking place and remain membranaceous.

Bonding film of the present invention is applicable to the manufacturing of two layers of FPC, but in this case, owing to contain TPI in the adhesive linkage, therefore in order to realize hot melt knot property, must apply the high temperature more than 200 ℃.Therefore, even thereby above-mentioned refractory layer preferably contains also can avoid thermal deformation to bring into play the high-fire resistance polyimides of enough shape stabilities under this hot conditions.

As above-mentioned high-fire resistance polyimides, there is no particular limitation, but can enumerate the non-thermal plasticity polyimide resin.More particularly, can enumerate various aromatic polyimides.Also have, there is no particular limitation for the molecular structures of the high-fire resistance polyimides that uses among the present invention etc., but, be described in detail by the manufacture method of enumerating acid dianhydride composition, two amine components and polyimides below as raw material monomer for preferred example.

Preferably contain the above non-thermal plasticity polyimides of 90 weight % in the above-mentioned refractory layer, more preferably contain more than the 95 weight %.In other words, also can contain high-fire resistance polyimides composition in addition in the above-mentioned refractory layer.

As other above-mentioned composition, can enumerate can with the blend of high-fire resistance polyimides, and can not damage the various resins of the rerum natura of refractory layer, and the various additives etc. that are used to improve the various characteristics of refractory layer.Wherein, preferably add filler in the present invention.By adding filler, can improve sliding, heat conductivity, electric conductivity, corona resistance, the circulation rigidity various characteristicses such as (loop stiffness) of the bonding film that is obtained.

There is no particular limitation for the filler that uses among the present invention, can enumerate the inorganic filler that comprises various inorganic compounds.More particularly, can enumerate oxides such as silica, mica, titanium oxide, aluminium oxide; Inorganic nitride such as silicon nitride, boron nitride; Phosphate cpd such as calcium monohydrogen phosphate, calcium phosphate etc.

The particle diameter of filler depends on the membrane property of the modification of wanting and the kind of the filler that added etc., therefore there is no particular limitation, but average grain diameter gets final product in the scope of 0.05～100 μ m usually, preferably in the scope of 0.1～75 μ m, more preferably in the scope of 0.1～50 μ m, further preferred in the scope of 0.1～25 μ m.If particle diameter less than this scope, then is difficult to reach modified effect,, then may damages superficiality significantly, or mechanical property is reduced significantly if surpass this scope.

The addition of filler also depends on the membrane property of the modification of wanting and the particle diameter of filler etc., therefore there is no particular limitation, but get final product in the scope of 0.01～100 weight portion with respect to 100 weight portion polyimides usually, preferably in the scope of 0.01～90 weight portion, more preferably in the scope of 0.02～80 weight portion.If the filler addition less than this scope, then is difficult to reach modified effect,, mechanical property is reduced significantly if surpass this scope.

There is no particular limitation for the thickness of above-mentioned refractory layer, as mentioned below, as long as its setting can make the tensile modulus of elasticity of vertical (the MD direction) and horizontal (TD direction) of the bonding film that is obtained be in the preset range.

In addition, there is no particular limitation for the thermal coefficient of expansion of refractory layer, but preferably be in the time of 50～200 ℃ in 4～30ppm/ ℃ the scope, more preferably is in 6～25ppm/ ℃ the scope, further preferably is in 8～22ppm/ ℃ the scope.

The thermal coefficient of expansion of refractory layer is in above-mentioned scope when above, adhesive linkage is set and thermal coefficient of expansion when forming bonding film much larger than metal forming, thereby the thermal behavior difference of bonding film and metal forming becomes big when laminated, makes the change in size of flexible metal-clad laminate both big sometimes.On the other hand, the thermal coefficient of expansion of refractory layer is during less than above-mentioned scope, and the thermal coefficient of expansion of bonding film is on the contrary much smaller than metal forming, thereby the thermal behavior when laminated still differs greatly, and makes the change in size of flexible metal-clad laminate both big sometimes.

＜high-fire resistance polyimides 〉

Be used as the non-thermal plasticity polyimides of the high-fire resistance polyimides of refractory layer, can be prepared as precursor, be prepared by making its imidizate with polyamic acid.

As the manufacture method of polyamic acid, can use a known blanking method, there is no particular limitation.Acid dianhydride composition and two amine components are dissolved in the organic solvent with reaching the first-class mole of essence separately, under controlled temperature conditions, stir until above-mentioned acid dianhydride composition and two amine component polymerizations and finish, thereby be prepared.The polyamic acid that obtains by this preparation method is organic solvent solution (below, for simplicity, be called " polyamic acid solution "), and the concentration of polyamic acid is generally 5～35 weight %, is preferably 10～30 weight %.If reach the concentration in this scope, then can form and be suitable for molecular weight of the present invention and solution viscosity.

As the polymerization of polyamic acid, can use a known blanking method and their combination.The polymerization of polyamic acid is characterised in that the interpolation order of monomer component.Therefore, can control the various rerum naturas of gained polyimides in proper order by the interpolation of control monomer component.Thereby in the present invention, the interpolation of monomer order can carry out suitably determining according to the final needed various characteristics of non-thermal plasticity polyimides that will obtain, so in the polymerization of polyamic acid, can add monomer component in proper order by any interpolation.

Though there is no particular limitation for the polymerization of this polyamic acid,, can enumerate following the whole bag of tricks as representational polymerization.Also have, these methods can be used separately, also can partially combinedly use.

1) make two amine components be dissolved in the organic polar solvent after, add and the equimolar acid dianhydride composition of two amine component essence, stir and make it reaction, carry out polymerization.

2) the acid dianhydride composition is had still less with comparing with it that two amine components of mole are dissolved in the organic polar solvent, stir and make it reaction, obtain containing the organic solvent solution that two ends have the prepolymer of anhydride group.Then, in pre-polymer solution, add two amine components and make acid dianhydride and two amine components in whole operations reach substantial equimolar amounts, stir, polymerization.

3) the acid dianhydride composition was had two amine components that win mole and was dissolved in the organic polar solvent with comparing with it, and stirred and make it reaction, obtained containing the organic solvent solution that two ends have amino prepolymer.Then, in pre-polymer solution, add the acid dianhydride composition and make acid dianhydride and two amine components in whole operations reach substantial equimolar amounts, stir, polymerization.

4) make the acid dianhydride composition be dissolved in the organic polar solvent after, add two amine components and it reached and mole such as acid dianhydride composition essence, stir and make it reaction.

5) equimolar in fact acid dianhydride composition and diamines mixture of ingredients are dissolved in the organic polar solvent, stir and make it reaction, carry out polymerization.

Also have, in above-mentioned polymerization, each monomer component (acid dianhydride composition and/or two amine components) can only be a kind of compound, also can contain two or more compounds.In addition, even add in the organic solvent, owing to the solubility for same solvent, these compounds do not dissolve sometimes, if but be scattered in equably in whole solvents, also can be counted as identical with the state of dissolving in fact.Therefore, the term of so-called " dissolving " can be replaced with " dispersion " in the method explanation above-mentioned 1)～5).

As the organic polar solvent that is used to make the polyamic acid polymerization, there is no particular limitation, so long as the solvent of solubilized polyamic acid gets final product, can use any solvent, but wherein preferably use amide solvent, that is, N, dinethylformamide, N, N-dimethylacetylamide, N-N-methyl-2-2-pyrrolidone N-etc., especially preferably use N, dinethylformamide, N, N-dimethylacetylamide.

As the monomer component that uses among the present invention, the known compound of suitable use, in particular for obtaining highly heat-resistant polyimide, preferably no matter the acid dianhydride composition still is two amine components is the aromatic series compounds.In other words, in the present invention, under the situation of preparation as the polyamic acid solution of high-fire resistance polyimide precursor, very preferably use aromatic tetracarboxylic acid's dianhydride, use aromatic diamine as two amine components as the acid dianhydride composition.

As the aromatic tetracarboxylic acid's dianhydride that can be used as the acid dianhydride composition in the present invention, there is no particular limitation, specifically, can enumerate, pyromellitic acid anhydride for example, 2,3,6,7-naphthalene tetracarboxylic acid dianhydride, 3,3 ', 4,4 '-biphenyl tetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarbacidic acidic dianhydride, 2,2 ', 3,3 '-bibenzene tetracarboxylic dianhydride, 3,3 ', 4,4 '-benzophenone tetracarboxylic dianhydride, 4,4 '-hydroxyl O-phthalic acid dianhydride, 2,2-two (3,4-dicarboxyl phenyl) propane dianhydride, 3,4,9,10-perylene tetracarboxylic dianhydride, two (3,4-dicarboxyl phenyl) propane dianhydride, 1, two (2,3-dicarboxyl phenyl) the ethane dianhydrides of 1-, 1,1-two (3,4-dicarboxyl phenyl) ethane dianhydride, two (2,3-dicarboxyl phenyl) methane dianhydride, two (3,4-dicarboxyl phenyl) ethane dianhydride, oxygen di-O-phthalic acid dianhydride (オキシジ Off Le acid two anhydrides), two (3,4-dicarboxyl phenyl) sulfone dianhydride, TOPOT 2,2 (Pyromellitic Acid monoesters acid anhydrides), ethylenebis (Pyromellitic Acid monoesters acid anhydrides), the analog of bisphenol-A two (Pyromellitic Acid monoesters acid anhydrides) and these compounds.These compounds can use separately, also can make up and form mixture and use with arbitrary proportion.

In above-mentioned aromatic tetracarboxylic acid's dianhydride, preferred especially the use is selected from pyromellitic acid anhydride, 3,3 ', 4,4 '-benzophenone tetracarboxylic dianhydride, 4,4 '-hydroxyl phthalic dianhydride, 3,3 ', 4, at least a compound in 4 '-biphenyl tetracarboxylic dianhydride.Also have,, the cohort of these four kinds of compounds is called " preferred acid dianhydride cohort " for the convenience that illustrates.If use these preferred acid dianhydride cohort polymeric polyamide acid, then can make the bonding film (particularly refractory layer) of acquisition have excellent various rerum naturas.

Be selected under the situation of at least a compound in the above-mentioned preferred acid dianhydride cohort in use, preferably use amount is, reaches 50 moles more than the % with respect to all acid two anhydride components, more preferably reaches 55 moles more than the %, further preferably reaches 60 moles more than the %.If the use amount of compound that is selected from these preferred acid dianhydride cohorts is less than above-mentioned lower limit, then the glass transition temperature of the polyimide film of Huo Deing (or refractory layer) became low, or the storage modulus when being heated is too descended, may cause making the film difficulty.

In addition, in preferred acid dianhydride cohort, when using pyromellitic acid anhydride, its consumption is preferably 40～100 moles of %, more preferably 45～100 moles of %, more preferably 50～100 moles of %.By using pyromellitic acid anhydride, be easy to make the glass transition temperature of polyimide film of acquisition and the storage modulus when being heated to remain in the preferred range with this amount ranges.

There is no particular limitation to can be used as the aromatic diamine of two amine components in the present invention, specifically, for example can enumerate 4,4 '-diamino-diphenyl propane, 4,4 '-diaminodiphenyl-methane, benzidine, 3,3 '-dichloro-benzidine, 3,3 '-dimethylbenzidine, 2,2 '-dimethylbenzidine, 3,3 '-dimethoxy benzidine, 2,2 '-dimethoxy benzidine, 4,4 '-diaminodiphenyl sulfide, 3,3 '-diamino diphenyl sulfone, 4,4 '-diamino diphenyl sulfone, 4,4 '-oxo benzidine, 3,3 '-oxo benzidine, 3,4 '-oxo benzidine, 1, the 5-diaminonaphthalene, 4,4 '-diamino-diphenyl diethylsilane, 4,4 '-diamino-diphenyl silane, 4,4 '-diamino-diphenyl ethyl phosphine oxide, 4,4 '-diamino-diphenyl-N-methyl amine, 4,4 '-diamino-diphenyl-N-phenyl amine, 1,4-diaminobenzene (P-pHENYLENE dI AMINE), 1, the 3-diaminobenzene, 1, the 2-diaminobenzene, two { 4-(4-amino-benzene oxygen) phenyl } sulfone, two { 4-(3-amino-benzene oxygen) phenyl } sulfone, 4,4 '-two (4-amino-benzene oxygen) biphenyl, 4,4 '-two (3-amino-benzene oxygen) biphenyl, 1, two (3-amino-benzene oxygen) benzene of 3-, 1, two (4-amino-benzene oxygen) benzene of 3-, 1, two (4-amino-benzene oxygen) benzene of 3-, 1, two (3-amino-benzene oxygen) benzene of 3-, 3,3 '-diaminobenzophenone, 4, the analog of 4 '-diaminobenzophenone and these compounds.These compounds can use separately, also can make up and form mixture and use with arbitrary proportion.

In the present invention, as two amine components, preferred sometimes the diamines (convenience in order to illustrate is called " rigidity diamines ") that uses with rigid structure.Specifically, rigid structure herein can be enumerated following general formula (1)

(still, the R in the formula ¹For being selected from following general formula group (2)

The group of the divalent aromatic radical of expression, the R in the formula ²Can be identical or different, be to be selected from H-, CH ₃-,-OH ,-CF ₃,-SO ₄,-COOH ,-CONH ₂, Cl-, Br-, F-and CH ₃Any group among the O-) Biao Shi structure.

State in the use under the situation that the rigidity diamines carries out the polyamic acid polymerization, preferably select the polymerization (for example 2) or 3 of the acquisition prepolymer in the above-mentioned polyamic acid polymerization) method).By using this polymerization, be easy to obtain elastic modelling quantity height, polyimide film that the moisture expantion coefficient is little.

There is no particular limitation for the rigidity diamines when obtaining prepolymer and the mol ratio of acid dianhydride, as the rigidity diamines: the acid dianhydride composition, be preferably 100: 70～100: 99 or 70: 100～99: 100, more preferably 100: 75～100: 90 or 75: 100～90: 100.If the mol ratio of rigidity diamines and acid dianhydride less than above-mentioned scope, then is difficult to reach the effect of improving elastic modelling quantity and moisture expantion coefficient, if surpass above-mentioned scope, it is too small then may linear expansion coefficient to occur, or tensile elongation drawback such as diminish.

In addition, as two amine components, also can be also with above-mentioned rigidity diamines and the diamines with flexible structure (convenience for explanation is called " flexible diamines ").And during with rigidity diamines and flexible diamines, as rigidity diamines with molar ratio computing: flexible diamines, be preferably 80: 20～20: 80, more preferably 70: 30～30: 70, more preferably 60: 40～30: 70.If the usage ratio of rigidity diamines surpasses above-mentioned scope, then the tensile elongation of the polyimide film of Huo Deing (refractory layer) diminishes easily, if less than this scope, then glass transition temperature is low excessively, or the storage modulus when being heated is low excessively, causes making the film difficulty sometimes.

Above-mentioned flexible diamines be meant have ether, the diamines of flexible structure such as sulfo group, ketone group, thioether group, more preferably enumerate following general formula (3)

(the R in the formula ³For being selected from following general formula group (4)

The group of the divalent organic group of expression, the R in the formula ⁴Can be identical or different, be to be selected from H-, CH ₃-,-OH ,-CF ₃,-SO ₄,-COOH ,-CONH ₂, Cl-, Br-, F-and CH ₃Any group among the O-.) expression compound.

Thus, as the polyimide film of refractory layer use, can thereby having the film that is in the expection characteristic in the above-mentioned scope, formation obtain among the present invention by determining and using the suitable acid dianhydride composition and kind, the compounding ratio of two amine components.Also have,, under the manufacture method method project of (II) bonding film, describe about the imidizate of polyamic acid.

(I-2) adhesive linkage and be used for its TPI

The adhesive linkage that bonding film of the present invention possesses contains TPI, and there is no particular limitation, gets final product so long as can show the layer of cementability under rated condition.

There is no particular limitation for TPI (broad sense) contained in the bond layer, and specifically, suitable use is TPI (narrow sense), polyamide thermoplastic acid imide, thermoplastic polyether acid imide, thermoplastic polyester acid imide etc. for example.Wherein, from the viewpoint of low moisture-absorption characteristics, especially preferably use the thermoplastic polyester acid imide.Also have, described in the claim scope, contained TPI comprises above-mentioned various polyimides in the adhesive linkage, refers to have thermoplastic sensu lato material.In addition, unless otherwise indicated, the term of " TPI " that uses in this specification is meant sensu lato material.

There is no particular limitation for the rerum natura of the TPI that uses among the present invention, but in various rerum naturas, more preferably glass transition temperature (Tg) is set within the limits prescribed.Specifically, the Tg of the TPI that uses among preferred the present invention is 150～300 ℃, more preferably 180～280 ℃.Also have, Tg can be obtained by the value of the flex point of the storage modulus of measuring by Measurement of Dynamic Viscoelasticity device (DMA).

If Tg is in the above-mentioned scope, it is laminated then not only can to use existing laminater that bonding film of the present invention and metal forming are carried out, and can avoid the hear resistance of the flexible metal-clad laminate both that obtained impaired.

There is no particular limitation for the manufacture method of above-mentioned TPI, but same with the high-fire resistance polyimides described in (I-1), can be by the polymerization of precursor polyamic acid, then imidizate is prepared.There is no particular limitation for the polymerization of polyamic acid, can adopt a known blanking method.Specifically, same with the high-fire resistance polyimides described in (I-1), select raw material monomer, create conditions etc. made polyamic acid and got final product.

Also have, for the TPI that uses among the present invention, identical with the high-fire resistance polyimides, can regulate various characteristics by various combinations, still to employed raw material monomer, as a rule, if it is big that the usage rate of rigidity diamines becomes, then Tg can uprise, and/or the storage modulus when being heated becomes big, the cementability of adhesive linkage and processability descend, and are worthless therefore.So, during the TPI that in making the present invention, uses, under two amine components and situation of the polymerization that is used for precursor polyamic acid with the rigidity diamines, the usage rate (containing ratio) of the rigidity diamines in then whole two amine components is preferably 40 moles below the %, more preferably 30 moles below the %, more preferably 20 moles below the %.

In addition, the same with refractory layer, in above-mentioned adhesive linkage, also can contain polyimides resin and various additive in addition.For example, the same with refractory layer, can also add filler in case of necessity.As filler in this case, can enumerate inorganic matter or organic matter filler, but there is no particular limitation, its concrete kind and use amount etc. can suit to select according to the required rerum natura of adhesive linkage.

There is no particular limitation for the thickness of above-mentioned adhesive linkage, but the same with refractory layer, as mentioned below, as long as its setting is in the scope of regulation the tensile modulus of elasticity of vertical (the MD direction) and horizontal (TD direction) of the bonding film that is obtained.

(I-3) rerum natura of bonding film

Bonding film of the present invention has the structure that has formed above-mentioned adhesive linkage on above-mentioned refractory layer and at least one surface at this refractory layer.Therefore, as bonding film of the present invention, can enumerate the two-layer structure of refractory layer/adhesive linkage, the three-decker of adhesive linkage/refractory layer/adhesive linkage.And, also can form two-layer structure is carried out repeatedly laminated structure, or also can comprise refractory layer and adhesive linkage layer in addition in case of necessity.

＜percent thermal shrinkage 〉

In the various characteristics of bonding film of the present invention, in the setting of percent thermal shrinkage, make the TD direction at least herein, greater than the MD direction.Also have, percent thermal shrinkage of the present invention is meant the value that obtains by the following method.

That is to say, will measure sample (bonding film or its tester) and be positioned over and be adjusted to 23 ℃, 55%RH and (wherein, " RH " expression " Relative Humidity: relative humidity " in) the room after 2 days, measure the size (L1) of film.Then, same sample 250 ℃ of down heating after 30 minutes, was placed 2 days in being adjusted to 25 ℃, the room of 60%RH, then size up (L2) again.Calculate percent thermal shrinkage by following formula (1) from L1 and the L2 that obtains.Also have, L1 and L2 are the specimen lengths of measuring on TD direction and MD direction.

Percent thermal shrinkage=-(L2-L1)/L1 * 100 ... (1)

If above-mentioned percent thermal shrinkage is described more specifically, then the percent thermal shrinkage of TD direction is to get final product more than+0.01%, be preferably+more than 0.03%, more preferably+more than 0.05%.On the other hand, the percent thermal shrinkage of MD direction is to get final product below-0.02%, be preferably-below 0.05%.Therefore, if the combination by TD direction and MD direction is stipulated percent thermal shrinkage, then the TD direction be more than+0.01% and the MD direction for to get final product below-0.02%, preferred TD direction be+0.03% or more and the MD direction is below-0.05%, and more preferably the TD direction is more than+0.05% and the MD direction is below-0.05%.

Bonding film of the present invention is suitable for the situation by hot-roll lamination manufactured FPC.Cast coating herein is to use with a pair of beaming roller one side pressing metal forming and bonding film and carries on one side, thereby make the method for the lamilated body of metal forming and bonding film effectively, but owing to be the method for metal forming and bonding film being carried out pressing by a pair of beaming roller, therefore to apply the stress of stretching, extension in the MD direction, on the TD direction, apply the stress of compression.

If stress application in such a way then makes bonding film have the residual strain of contraction on the MD direction, on the TD direction, has the residual strain of expansion.And, carry out etching and when forming circuit at lamilated body, and when carrying out remelting scolding tin for assembling parts, this strain is released, and causes the change in size that the MD direction is shunk, the TD direction expands to metal forming/bonding film.Therefore, during by hot-roll lamination manufactured lamilated body, if use thermal contraction at MD direction and the essentially identical bonding film of TD direction, then aspect the change in size in etching work procedure and remelting scolding tin operation, deviation can take place in MD direction and TD direction.

Technology is in the past considered fully for the residual strain problem of this TD direction and MD direction.Therefore, though known to the technology that like that percent thermal shrinkage under the rated condition is set in shown in the patent documentation 4～6 in the particular range, the technological thought that changes the percent thermal shrinkage of TD direction and two aspects of MD direction is unknown fully.The present invention finds, based on this technological thought, in order to have suppressed the change in size deviation of MD direction and TD direction, it is effective setting the percent thermal shrinkage of TD direction higher than the percent thermal shrinkage of MD direction.Therefore, concrete scope to percent thermal shrinkage is furtherd investigate, the result shows if to the above-mentioned lower limit of the concrete setting of the percent thermal shrinkage of TD direction, to the above-mentioned higher limit of the concrete setting of the percent thermal shrinkage of MD direction, particularly under the situation of the lamilated body of the laminate structures that contains metal forming/bonding film by the hot-roll lamination manufactured, be effective then for the change in size deviation that suppresses all directions.

＜tensile modulus of elasticity 〉

There is no particular limitation for other characteristic of bonding film of the present invention, but preferably its tensile modulus of elasticity is defined in the predetermined scope.Specifically, for any direction in MD direction and the TD direction, all preferred its tensile modulus of elasticity is in the scope of 5.0～11GPa, more preferably is in the scope of 5.5～10GPa.Also have, for tensile modulus of elasticity, the オ-トグラ Off S-100-C that for example can use society of Shimadzu Seisakusho Ltd. to make measures according to AST M D882.

Above-mentioned tensile modulus of elasticity is during less than above-mentioned scope, is subject to the influence of tension force in laminated, thereby can produce different thermal stress on MD direction and TD direction, and the change in size of the lamilated body of Huo Deing (flexible metal-clad laminate both etc.) is big sometimes.On the other hand, when tensile modulus of elasticity surpassed above-mentioned scope, the bendability of the flexible metal-clad laminate both that is obtained was poor sometimes.

Here, the tensile modulus of elasticity of adhesive linkage that contains TPI is usually little than the refractory layer that contains the high-fire resistance polyimides, and therefore along with the increase of thickness of adhibited layer ratio, the tensile modulus of elasticity of bonding film trends towards reduction.Thereby, for the above-mentioned refractory layer that constitutes bonding film and the thickness separately of adhesive linkage, as long as suitably adjust satisfying above-mentioned tensile modulus of elasticity and reach under the prerequisite of the gross thickness that is fit to purposes.In following embodiment, as the 3-tier architecture of adhesive linkage/refractory layer/adhesive linkage, illustration thickness be the structure of 2 μ m/10 μ m/2 μ m, but be not limited thereto certainly.

＜thermal coefficient of expansion 〉

The thermal coefficient of expansion of bonding film of the present invention preferably is specified in the predetermined scope.As mentioned below, bonding film of the present invention is applicable to the form of bonded metal paper tinsel at least one surface, promptly, be applicable to the application of being processed into flexible metal-clad laminate both, if but consider dimensional stability when being processed into flexible metal-clad laminate both, the thermal coefficient of expansion of bonding film and the thermal coefficient of expansion of laminated metal forming are adapted.

Specifically, the value of the thermal coefficient of expansion of bonding film under 200～300 ℃ preferably is adjusted in the thermal coefficient of expansion of metal forming ± 6ppm/ ℃ the scope.If thermal coefficient of expansion exceeds beyond this scope, then the thermal coefficient of expansion of bonding film becomes big with the difference of the thermal coefficient of expansion of the metal forming of being fitted.Therefore, the expansion when bonding film and metal forming are fitted, the difference of shrinking behavior become big, residual strain in the flexible metal-clad laminate both that is obtained, and the size changing rate of removing after the metal forming has the situation that becomes big.

Also have, the thermal coefficient of expansion of bonding film can be regulated by the ratio that changes refractory layer thickness and thickness of adhibited layer.

(II) manufacture method of bonding film

(II-1) method of the bonding film of use gel coating manufactured

There is no particular limitation for the manufacture method of bonding film of the present invention, as long as can prepare the method for bonding film, also can be by " gel coating method " method at the above-mentioned adhesive linkage of formation on the face of refractory layer or on two faces with above-mentioned refractory layer and adhesive linkage.

Above-mentioned " gel coating method " is meant, at first will coat on the support as the polyamic acid solution curtain coating of the precursor of high-fire resistance polyimides, carry out drying, part imidizate then, thereby the membranaceous intermediate of formation self-supporting (below, be called " gel mould "), coating contains the solution of TPI or as the method for the polyamic acid solution of the precursor of TPI at least one surface of this gel mould.

Therefore, if the manufacture method of bonding film of the present invention is described more specifically, then it has the gel mould operation that forms above-mentioned gel mould and the laminated operation of laminated TPI or its precursor on gel mould.And, in manufacture method of the present invention, very preferably contain the laminate film that obtains for after the laminated operation, Yi Bian apply the stretching imidizate operation that imidizate is carried out in stretch processing on one side in the TD direction.

＜gel mould forms operation 〉

Gel in the manufacture method of the present invention forms operation, and there is no particular limitation, so long as the membranaceous operation of making gel mould of organic solvent solution (convenience for explanation is called " high-fire resistance polyimide precursor solution ") formation that will contain as the polyamic acid of high-fire resistance polyimide precursor gets final product.In other words, above-mentioned gel mould formation operation also can be called refractory layer formation operation.

Above-mentioned gel mould can obtain in the following manner, promptly, the high-fire resistance polyimide precursor solution is expressed into from the mouth mould on the level and smooth support continuously and smoothly, makes a part of solvent evaporates (making its drying) by heating then, make it imidizate simultaneously at least in part.As above-mentioned support, there is no particular limitation, but can enumerate endless belt or the rotary drum with the surface that is easy to peel off gel mould.There is no particular limitation for the Facing material of these endless belts or rotary drum, can enumerate metal or fluororesin etc.Also there is no particular limitation for the material of mouthful mould and structure, can wait according to the kind of the size of the thickness of the refractory layer that will form and width, the final bonding film that will obtain or structure or high-fire resistance polyimide precursor solution or rerum natura and select optimum size and structure.

As above-mentioned imidizate method, what be widely known by the people most is thermal curing method (hot-imide method) that is only undertaken by heat and these two kinds of methods of chemosetting method (chemical imidizate method) of using chemical dehydrator.Can adopt any method, but, especially preferably adopt chemosetting method (chemical imidizate method) from giving the more angle of high productivity.

There is no particular limitation for above-mentioned chemical dehydrator, so long as the dehydration ring closure agent of polyamic acid gets final product, as its principal component, specifically, preferably use for example aliphatic anhydride, aromatic anhydride, N, N '-dialkyl group carbodiimides, lower aliphatic halide, halo lower aliphatic acid anhydrides, arylsulfonyl dihalide, thionylhalides or 2 kinds mixture wherein.In these compounds, especially preferably use aliphatic anhydride and aromatic anhydride.

In addition, when carrying out above-mentioned chemosetting (chemical imidizate), can use the curing agent that contains above-mentioned chemical dehydrator and catalyst.There is no particular limitation for above-mentioned catalyst, as long as have the composition of effect of the promotion dehydration ring closure effect of chemical dehydrator for polyamic acid, specifically, for example can use aliphatic tertiary amine, aromatic nitrile base, hetero ring type tertiary amine.In these compounds, especially preferably use nitrogen-containing heterocycle compounds such as imidazoles, benzimidazole, isoquinolin, quinoline or beta-picoline.

There is no particular limitation for the use amount of above-mentioned chemical dehydrator and catalyst, get final product so long as can reach the amount of the imidizate of expected degree, as chemical dehydrator, with respect to 1 mole of the amic acid unit in the polyamic acid contained in the polyamic acid solution that has added chemical dehydrator and catalyst, be preferably 0.5～5 mole, more preferably 0.7～4 mole.In addition, as catalyst, with respect to 1 mole of the amic acid unit in the polyamic acid contained in the polyamic acid solution that has added chemical dehydrator and catalyst, be preferably 0.05～3 mole, more preferably 0.2～2 mole.If chemical dehydrator and catalyst consumption less than above-mentioned scope, by chemical imidizate deficiency, may rupture in the sintering procedure, or the situation that mechanical strength is descended.In addition, if the use amount of chemical dehydrator and catalyst surpasses above-mentioned scope, then imidizate carries out too fastly, is difficult to be cast into membranaceous sometimes.

As described in above-mentioned (I-1), above-mentioned high-fire resistance polyimide precursor solution can also contain inorganic filler.There is no particular limitation for the adding method of this filler, specifically, for example can enumerate (1) and add polymerization liquid before the polyamic acid polymerization or in the polymerization process; (2) after the polyamic acid polymerization is finished, use mixing fillers such as three roller mixing rolls; (3) in addition preparation contains the dispersion liquid of filler, and it such as is mixed at the whole bag of tricks with polyamic acid.

In these methods, preferred (3) are mixed into method in the polyamic acid solution with its dispersion liquid that contains filler.If adopt this method, particularly since can be before will forming gel mould mixed fillers, therefore can reduce bonding film to the full extent and make the possibility that the filler residual and that bring of filler on the line is sneaked into.

Preparation contains the method for dispersion liquid of above-mentioned filler, and there is no particular limitation, the filler that uses can be added to be modulated into dispersion liquid in the appropriate solvent, as solvent, preferably uses the organic polar solvent identical with the polyamic acid solvent.In addition, for filler being disperseed well and making the dispersity stabilisation, can also in the scope that does not influence the film rerum natura, use additives such as dispersant, tackifier.

＜laminated operation 〉

Laminated operation in the manufacture method of the present invention is so long as form at least one surface of the gel mould that obtains in the operation at above-mentioned gel mould, coating contains the organic solvent solution of TPI (for the convenience that illustrates, be called " TPI solution ") or contain the TPI precursor---the organic solvent solution of polyamic acid is (for the convenience that illustrates, be called " TPI precursor solution "), and the operation that heats, just there is no particular limitation.

Method at gel film surface coating thermoplastic polyimide solution or TPI precursor solution is not particularly limited, can suitably select curtain coating coating, spraying, dip coated etc. in the past known method use.In the following embodiments, adopted the curtain coating rubbing method that uses mouthful mould, but the present invention is not limited thereto certainly.

Gel mould for being coated with TPI solution or TPI precursor solution makes solvent evaporates carry out drying by heating.There is no particular limitation for the drying means of this moment, can adopt known various drying means, but the method for heating and/or air-supply is the easiest.When the temperature during above-mentioned heating was too high, solvent acutely volatilized, and therefore the vestige of this volatilization can become the important cause of formation tiny flaw in the bonding film that is obtained, thereby the boiling point of preferred employed solvent is less than+50 ℃.

Also have, form in the operation, after curtain coating coating high-fire resistance polyimide precursor solution, carry out under the dry situation at gel mould, there is no particular limitation for its heating means, identical with laminated operation, can adopt known the whole bag of tricks, preferably use the method for above-mentioned heating and/or air-supply.

＜stretching imidizate operation 〉

If the stretching imidizate operation in the manufacture method of the present invention is fixed the TD direction two ends of the laminate film that obtains in the laminated operation, make the TD direction be stretched to stretching ratio on one side above 1.0 times, carry out the operation of imidizate on one side, then there is no particular limitation in addition.

As mentioned above, bonding film of the present invention is set to the percent thermal shrinkage height of the percent thermal shrinkage of TD direction than MD direction.There is no particular limitation for the establishing method of this percent thermal shrinkage, as a kind of preferable methods, Yi Bian can enumerate the laminate film method that heating stretches on the TD direction that will obtain in the laminated operation on one side.The level of stretch of this moment is so long as surpass 1.0 times stretching and get final product, and is preferably more than 1.1 times, below 2.0 times.In addition, there is no particular limitation for the heating-up temperature during stretching, gets final product more than 100 ℃, more preferably more than 200 ℃.When being in this temperature range, can under the situation that laminate film is not caused physical hazard, stretch well.

Imidizate in the stretching imidizate operation is handled and is used the acid imide method described in the above-mentioned gel mould formation operation to get final product, if consider the productivity of bonding film, then preferred especially above-mentioned stretch processing and imidizate are handled and carried out simultaneously.Specifically, by on one side laminate film being extended, handle in preferred 250～600 ℃ scope on one side, can carry out heat treated fully.Thus, desolvate while just can extend to remove basically, and carried out imidizate simultaneously.

(II-2) use coextrusion-curtain coating rubbing method to make the method for bonding film

As the manufacture method of bonding film of the present invention, except above-mentioned " (II-1) method of the bonding film of use gel coating manufactured ", can also be to use the method for coextrusion-curtain coating rubbing method.Above-mentioned " coextrusion-curtain coating rubbing method " is meant the film manufacturing method with following operation, the solution that is about to high patience polyimide precursor solution and contains the solution of TPI or contain the TPI precursor is provided to simultaneously to have in the two-layer above extrusion shaping machine of extrusion molding with mouthful mould, makes two kinds of solution form at least double-layer films shape thing and extrudes from the outlet of above-mentioned mouthful of mould.Extrusion molding more than two-layer is expressed on the level and smooth support continuously with above-mentioned two kinds of solution of extruding mouthful mould, makes at least a portion volatilization of the solvent of the membranaceous thing of multi-layer thin on the above-mentioned support then, thus the multilayer film that obtains having self-supporting.Again this multilayer film is peeled off from above-mentioned support, used high temperature (250～600 ℃) that this multilayer film is carried out heat treated fully at last, remove basically and desolvate, carry out imidizate simultaneously, thereby obtain the bonding film of purpose.In addition, in order to improve the melt fluidity of adhesive linkage, also can reduce the imidizate rate wittingly and/or make dissolvent residual.

Bonding film of the present invention is by coextrusion-curtain coating rubbing method, on at least one face of high-fire resistance polyimide layer, formed the bonding film of thermoplastic polyimide layer, the percent thermal shrinkage of wishing the TD direction is more than+0.01% and the percent thermal shrinkage of MD direction is below-0.02%, the percent thermal shrinkage of preferred TD direction is more than+0.03% and the percent thermal shrinkage of MD direction is below-0.05%, and the percent thermal shrinkage of preferred especially TD direction is more than+0.05% and the percent thermal shrinkage of MD direction is below-0.05%.Cast coating is to utilize a pair of beaming roller one side pressing metal forming and bonding film to carry on one side, thereby make the method for the laminated film of metal forming effectively, but, owing to be the method that metal forming and bonding mould is closed by a pair of beaming roller, therefore to be applied on the MD direction stress that stretches, on the TD direction, compresses.This stress makes residual contraction strain on the MD direction, residual expansion strain on the TD direction, and, when laminated film etching forms circuit to metal forming, and can discharge this residual strain when carrying out remelting scolding tin, the change in size that causes shrinking on the MD direction, expands on the TD direction for assembling parts.Therefore, if adopt cast coating, use on the MD direction and the essentially identical bonding film manufacturing metal-clad laminate plate of the thermal contraction on the TD direction, then the change in size in etching work procedure and the remelting scolding tin operation is having very big-difference on the MD direction He on the TD direction.In order to suppress above-mentioned deviation, the percent thermal shrinkage that the percent thermal shrinkage on the TD direction is higher than on the MD direction is effective.

About making percent thermal shrinkage on the TD direction be higher than the concrete grammar of the percent thermal shrinkage on the MD direction, there is no particular limitation, but described in the project of preferred as " (II-1) use the method＜stretching imidizate operation of the bonding film of gel coating manufactured〉", by being heated to more than 100 ℃ on one side, preferably carrying out stretch processing in the TD direction on one side more than 200 ℃ and finish.If the productivity of considering, then preferred especially this stretch processing and imidizate are handled and are carried out simultaneously.

About from having extrusion molding more than two-layer with the high-fire resistance polyimide precursor solution of extruding mouthful mould with contain the solution of TPI or contain the volatilization method of the solvent in the solution of TPI precursor, there is no particular limitation, described in the project of " (II-1) use the method＜laminated operation of the bonding film of gel coating manufactured〉", the method for heating and/or air-supply is the easiest method.Temperature during about above-mentioned heating, also as stating content, if too high, then solvent acutely volatilizees, and the vestige of this volatilization can become the important cause that forms tiny flaw in the bonding film that is obtained, thereby the boiling point of preferred employed solvent is less than+50 ℃.

Above-mentioned " have two-layer above extrusion molding with a mouth mould " is not particularly limited; so long as multilayer film formation gets final product with membrana oralis; can use known in the past mouth mould with all structures, as the preferred especially kind of using, can illustration current divider mouth mould or many differences mouth of pipe mould.

About the imidizate method in " use coextrusion-curtain coating rubbing method make the method for bonding film ", also can adopt in thermal curing methods and the chemosetting method any, from giving the more angle of high productivity, especially preferably adopt the chemosetting method.About the chemosetting method, use the method described in the project of " (II-1) use method＜gel mould of the bonding film of gel coating manufactured to form operation〉" to get final product.

(III) application of the present invention

Bonding film of the present invention is suitable for containing the manufacturing of the lamilated body of polyimide layer.That is to say, in the present invention, comprise the lamilated body that uses above-mentioned bonding film to make.The concrete structure of above-mentioned lamilated body is not particularly limited, and constitutes as representativeness, can enumerate the lamilated body that has in the structure of the surperficial laminated metal level of bonding film.

There is no particular limitation for the manufacture method of above-mentioned lamilated body, but for bonding film of the present invention, can enumerate laminating, preferably by cast coating metal forming is bonded at least one lip-deep method.

As laminated metal on above-mentioned bonding film, there is no particular limitation, but using lamilated body of the present invention to form flexible metal-clad laminate both, be used under the situation of electronic equipment, electrical equipment purposes, for example can enumerate the metal forming that contains copper or copper alloy, stainless steel or its alloy, nickel or nickel alloy (comprising 42 alloys), aluminum or aluminum alloy etc.In addition, for common flexible metal-coated laminate, use the Copper Foil of rolled copper foil, electrolytic copper foil and so on mostly, these Copper Foils also are preferred the use in the present invention.In addition, can also be at the coating of the surface of these metal formings antirust coat, refractory layer or adhesive linkage.

In addition, in the present invention, comprise the FPC that uses above-mentioned bonding film or above-mentioned lamilated body to form.Specifically, can enumerate flexible print circuit board (FPC).There is no particular limitation for the manufacture method of above-mentioned flexible print circuit board, specifically, for example can enumerate metal forming and bonding rete are closed, and carries out the pattern etch processes, forms the method for desirable pattern circuit on metal forming.For the present invention, in the manufacturing of this FPC, adopt cast coating to get final product in the step that metal forming and bonding rete are closed.Thus, can suppress change in size to take place carrying out various adding man-hour by the flexible metal-clad laminate both of hot-roll lamination manufactured.

Below, based on embodiment and comparative example the present invention is described more specifically, but the present invention is not limited thereto.Those skilled in the art can carry out various changes, modifications and changes in not departing from the scope of the present invention.Also have, percent thermal shrinkage and size changing rate in following examples and the comparative example are estimated in the following manner.

(percent thermal shrinkage)

At first, according to two edge MD directions, all the other two edge TD directions are cut into the square that the length of side is about 20cm, it is measured as percent thermal shrinkage use sample with the bonding film that obtains.

This percent thermal shrinkage measured to be positioned over sample be adjusted in 23 ℃, the room of 55%RH after 2 days, measure film size (L1).Then, same percent thermal shrinkage is measured with sample 250 ℃ of heating after 30 minutes down, in being adjusted to 25 ℃, the room of 60%RH, placed 2 days again, measure same percent thermal shrinkage then and measure film size (L2) with sample, calculate percent thermal shrinkage by following formula (1), estimate.

Percent thermal shrinkage=-(L2-L1)/L1 * 100 ... (1)

(size changing rate)

Remove the size changing rate of front and back for metal forming,, measure in the following manner and calculate with reference to JIS C6481.That is, from flexible metal-clad laminate both, downcut the square sample that the length of side is about 20cm, be equivalent on this specimen surface on the foursquare four corners position that the length of side is about 15cm, forming diameter is the hole of 1mm.Also have, make the length of side be about the square sample of 20cm and foursquare two edge MD directions that the length of side is about 15cm, all the other two edge TD directions.In addition, make this two foursquare center basically identicals.Then this sample (having the flexible metal-clad laminate both in 4 holes) is carried out etching, remove metal forming, in 23 ℃, the thermostatic chamber of 55%RH, placed 24 hours then.Then with this sample 250 ℃ of down heating 30 minutes, in 23 ℃, the thermostatic chamber of 55%RH, placed 24 hours afterwards.The Determination of distance value that adjacent holes in 4 holes of the flexible metal-clad laminate both before the etching is mutual is as D1, the Determination of distance value that adjacent holes on the sample after etching and the heat treatment is mutual is as D2, press the size changing rate that following formula (2) calculates the heating front and back, estimate.Also have, above-mentioned size changing rate is that MD direction and TD direction two aspects are measured.

Size changing rate (%)=(D2-D1)/D1} * 100 ... (2)

(synthesis example 1 of polyamic acid :) as the polyamic acid of high-fire resistance polyimide precursor

At the N that is cooled to 10 ℃, dinethylformamide (below, suitably be called " DMF ") among the 239kg, 4 of dissolving 6.9kg, 4 '-oxo benzidine (below, suitably be called " ODA "), the p-phenylenediamine (PPD) of 6.2kg (below, suitably be called " p-PDA "), 9.4kg 2, two (4-(4-amino-benzene oxygen) phenyl) propane of 2-(below, suitably be called " BAPP "), add 10.4kg pyromellitic acid anhydride (below, suitably be called " PMDA ") then and stirred 1 hour, make it dissolving.For the solution that obtains, add the benzophenone tetracarboxylic dianhydride (below, suitably be called " BTDA ") of 20.3kg again and stirred 1 hour, make its dissolving, make reactant liquor.

With the DMF solution of the PMDA of preparation (PMDA: DMF=0.9kg: 7.0kg) slowly add in the above-mentioned reactant liquor, reach 1 * 10 to viscosity in addition ²Stop during Pasec adding.Then, stirred 1 hour, the rotary viscosity that obtains solid concentration and be under the 18 weight %, 23 ℃ is the organic solvent solution (being called for simplicity, " polyamic acid solution (a1) ") of the polyamic acids (a1) of 3500 pools.

(synthesis example 2 of polyamic acid :) as the polyamic acid of high-fire resistance polyimide precursor

In 239kg was cooled to 10 ℃ DMF, ODA, the p-PDA of 6.8kg of dissolving 12.6kg added the PMDA of 15.6kg then and stir and dissolved in 1 hour.For the solution that is obtained, add the BTDA of 12.2kg, stir again and made its dissolving in 1 hour.For the solution that obtains, add the TOPOT 2,2 (trimellitic acid monoesters acid anhydrides) (below, suitably be called " TMHQ ") of 5.8kg again, stir and made its dissolving in 2 hours, make reactant liquor.

With the DMF solution of the PMDA of preparation (PMDA: DMF=0.9kg: 7.0kg) slowly add in the above-mentioned reactant liquor, reach 1 * 10 to viscosity in addition ²Stop during Pasec adding.Then, stirred 1 hour, the rotary viscosity that obtains solid concentration and be under the 18 weight %, 23 ℃ is the organic solvent solution (being called for simplicity, " polyamic acid solution (a2) ") of the polyamic acids (a2) of 3500 pools.

(synthesis example 3 of polyamic acid :) as the polyamic acid of the inferior imide precursor of thermoplastic poly

Capacity be two (4-(4-amino-benzene oxygen) phenyl) sulfones of adding DMF, the 11.72kg of 78kg in 300 liters the retort (below, suitably be called " BAPS "), under blanket of nitrogen, stir on one side, slowly add 3 of 7.17kg on one side, 3 ', 4,4 '-biphenyl tetracarboxylic dianhydride (below, suitably be called " BPDA ").Then, add 3,3 ', 4 of 0.56kg, 4 '-ethylene glycol bisthioglycolate benzoic ether tetracarboxylic dianhydride (below, suitably be called " TMEG "), in ice bath, stirred 30 minutes.In addition the TMEG of 0.55kg is dissolved among the DMF of 2kg and is mixed with solution, while pay close attention to viscosity it is slowly added in the above-mentioned reaction solution, and stir.Viscosity reaches 1 * 10 ²Stop during Pasec adding, add the DMF of 146.3kg again and carry out the stirring of grace time, thereby obtain the organic solvent solution (being called for simplicity, " polyamic acid solution (b1) ") of polyamic acid (b1).

(synthesis example 4 of polyamic acid :) as the polyamic acid of TPI precursor

Capacity be add in 300 liters the retort 78kg DMF, 11.56kg 2, two (4-(4-amino-benzene oxygen) phenyl) propane (BAPP) of 2-, on one side under blanket of nitrogen, stir, slowly add 3 of 7.87kg on one side, 3 ', 4,4 '-biphenyl tetracarboxylic dianhydride (BPDA).Then, add the TMEG of 0.38kg, in ice bath, stirred 30 minutes.In addition the TMEG of 0.2kg is dissolved among the DMF of 2kg and is mixed with solution, while pay close attention to viscosity it is slowly added in the above-mentioned reaction solution, and stir.Viscosity reaches 1 * 10 ²Stop during Pasec adding, add the DMF of 146.3kg again and stir fully, thereby obtain the organic solvent solution (being called for simplicity, " polyamic acid solution (b2) ") of polyamic acid (b2).

(synthesis example 5 of polyamic acid :) as the polyamic acid of TPI precursor

At capacity is DMF, the BAPS of 117.2g that adds 780g in the glass system flask of 2000ml, under blanket of nitrogen stir on one side, slowly add the BPDA of 71.7g on one side.Then, add the TMEG of 5.6g, in ice bath, stirred 30 minutes.In addition the TMEG of 5.5g is dissolved among the DMF of 20g and is mixed with solution, while pay close attention to viscosity it is slowly added in the above-mentioned reaction solution, and stir.Viscosity reaches 1 * 10 ²Stop during Pasec adding and stirring, thereby obtain TPI precursor polyamic acid solution (being called for simplicity, " polyamic acid solution (b3) ").

(synthesis example 6 of polyamic acid :) as the polyamic acid of TPI precursor

At capacity is DMF, the BAPP of 115.6g that adds 780g in the glass system flask of 2000ml, under blanket of nitrogen stir on one side, slowly add the BPDA of 78.7g on one side.Then, add the TMEG of 3.8g, in ice bath, stirred 30 minutes.In addition the TMEG of 2.0g is dissolved among the DMF of 20g and is mixed with solution, while pay close attention to viscosity it is slowly added in the above-mentioned reaction solution, and stir.Viscosity reaches 1 * 10 ²Stop during Pasec adding and stirring, thereby obtain TPI precursor polyamic acid solution (being called for simplicity, " polyamic acid solution (b4) ").

(embodiment 1)

For the polyamic acid solution as the high-fire resistance polyimide precursor (a 1) that obtains in the synthesis example 1, add acetic anhydride, as the isoquinolin of catalyst as chemical dehydrator.As addition, with respect to 1 mole of the amic acid unit of polyamic acid (a1), acetic anhydride is 2 moles, and isoquinolin is 0.5 mole.

Then, extrude above-mentioned polyamic acid solution (a1) continuously by the mould of the difference mouth of pipe more than three layers (below be also referred to as " T mouth mould "), it is about 10 μ m after carrying out curtain coating and make its drying on the stainless steel endless belt that navigates on 20mm place below this T mouth mould thick.After the film of this polyamic acid (a1) being carried out 130 ℃ * 100 seconds heating, peel off, form self-supporting gel mould (a1) from the endless belt.

Then, use two T mouth moulds, on two faces of gel mould (a1) continuously coating carry out 150 ℃ * 30 seconds heating as the polyamic acid solution (b1) of TPI precursor and to be about 2 μ m after making its drying thick.The film that is obtained is fixed on the anchor clamps of expander, by increasing the expander spacing jig stretching ratio that makes the TD direction that stretches is 1.1 times, carries out drying, imidizate simultaneously under 300 ℃ * 30 seconds, 400 ℃ * 50 seconds, 450 ℃ * 10 seconds condition.Thus, obtained having the high-fire resistance polyimide layer of 10 μ m and the bonding film of the present invention of the 2 μ m thermoplastic polyimide layers that on its two sides, form.

Rolled copper foil (trade name: BHY-22B-T at the both sides of the bonding film that obtains Continuous Heat lamination 18 μ m; ジヤパ Application エ Na ジ-society makes); and in Copper Foil both sides use protective material (trade name: アピカ Le 125NPI; Kanegafuchi Chemical Industry Co., Ltd makes); lamination is: polyimide film tension force 0.4N/cm; 380 ℃ of laminating temperatures; lamination pressure 196N/cm (20kgf/cm); laminate speed 1.5m/ minute, be made as the flexible metal-clad laminate both of lamilated body of the present invention.

Calculate and estimate the percent thermal shrinkage of the bonding film that is obtained with above-mentioned formula (1).In addition, calculate and estimate the flexible metal-clad laminate both size changing rate that is obtained with above-mentioned formula (2).It the results are shown in the table 1.

(embodiment 2)

Except replacing the precursor polyamic acid of polyamic acid solution (a1) as the high-fire resistance polyimides, make bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 1 with polyamic acid solution (a2).

(embodiment 3)

Except replacing the precursor polyamic acid of polyamic acid solution (b1) as TPI, make bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 1 with polyamic acid solution (b2).

(embodiment 4)

Except replacing the precursor polyamic acid of polyamic acid solution (b1) as TPI, make bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 2 with polyamic acid solution (b2).

(comparative example 1)

When being fixed on the stretching of carrying out the TD direction on the expander anchor clamps except the film that will be obtained, making its stretching ratio is outside 1.0 times, makes bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 1.

(comparative example 2)

When being fixed on the stretching of carrying out the TD direction on the expander anchor clamps except the film that will be obtained, making its stretching ratio is outside 1.0 times, makes bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 2.

Table 1

As shown in table 1, it is big that the result is to use percent thermal shrinkage to be in the size changing rate of the flexible metal-clad laminate both that the bonding film beyond the prescribed limit makes, relative therewith, it is little to use percent thermal shrinkage to be in the size changing rate of the flexible metal-clad laminate both that the bonding film in the prescribed limit makes.

(embodiment 5)

Make the precursor polyamic acid solution (a1) of the high-fire resistance polyimides that obtains in the synthesis example 1 contain following chemical dehydrator and catalyst.

As chemical dehydrator, with respect to the 1 mole of acetic anhydride that adds 2 moles in the amic acid unit in the precursor polyamic acid (a1) of high-fire resistance polyimides.In addition, as catalyst, with respect to the 1 mole of isoquinolin that adds 1 mole in the amic acid unit in the precursor polyamic acid (a1) of high-fire resistance polyimides.

And, make the precursor polyamic acid solution (b3) of the TPI that obtains in the synthesis example 5 contain following chemical dehydrator and catalyst.

As chemical dehydrator, with respect to the 1 mole of acetic anhydride that adds 2 moles in the amic acid unit in the precursor polyamic acid (b3) of TPI.In addition, as catalyst, with respect to the 1 mole of isoquinolin that adds 0.5 mole in the amic acid unit in the precursor polyamic acid (b3) of TPI.

Then, by the mould of the difference mouth of pipe more than three layers (being also referred to as " T mouth mould "), according to skin is the precursor polyamic acid solution (b3) of TPI, internal layer is the order of the precursor polyamic acid solution (a1) of high-fire resistance polyimides, extrude each polyamic acid solution continuously, it is carried out curtain coating on the stainless steel endless belt that navigates on 20mm place below this T mouth mould.After this resin molding being carried out 130 ℃ * 100 seconds heating, peel off the self-supporting gel mould from the endless belt and be fixed on the expander anchor clamps, to carry out stretching ratio on the TD direction be 1.1 times stretching by increasing the expander spacing jig, carries out drying, imidizate simultaneously under 300 ℃ * 30 seconds, 400 ℃ * 50 seconds, 450 ℃ * 10 seconds condition.Thus, obtaining each thermoplastic polyimide layer is that 4 μ m, high-fire resistance polyimide layer are the bonding film of the present invention of 17 μ m.

The rolled copper foil of heat lamination 18 μ m (trade name: BHY-22B-T, ジヤパ Application エ Na ジ-society makes) and the heat lamination of using protective material to carry out in the Copper Foil both sides again continuously in the both sides of the bonding film that obtains.(trade name: アピカ Le 125NPI, Kanegafuchi Chemical Industry Co., Ltd makes), lamination is: polyimide film tension force 0.4N/cm, 380 ℃ of laminating temperatures, lamination pressure 196N/cm (20kgf/cm), laminate speed 1.5m/ branch is made as the flexible metal-clad laminate both of lamilated body of the present invention.

Calculate and estimate the percent thermal shrinkage of the bonding film that is obtained with above-mentioned formula (1).In addition, calculate and estimate the flexible metal-clad laminate both size changing rate that is obtained with above-mentioned formula (2).It the results are shown in the table 2.

(embodiment 6)

Except replacing the precursor polyamic acid of polyamic acid solution (a1) as the high-fire resistance polyimides, make bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 5 with polyamic acid solution (a2).

(embodiment 7)

Except replacing the precursor polyamic acid of polyamic acid solution (b3) as TPI, make bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 5 with polyamic acid solution (b4).

(embodiment 8)

According to the order of the precursor polyamic acid solution (b3) of the precursor polyamic acid solution (a1) of the precursor polyamic acid solution (b3) of TPI, high-fire resistance polyimides, TPI, discharge the precursor polyamic acid solution (b3) of the TPI that obtains in the precursor polyamic acid solution (a1) of the high-fire resistance polyimides that obtains in the synthesis example 1 and the synthesis example 5 continuously by the mould of the difference mouth of pipe more than three layers.The solution of discharging is carried out curtain coating on stainless steel endless belt.After this resin molding being carried out 130 ℃ * 600 seconds heating, peel off the self-supporting gel mould from the endless belt and be fixed on the expander anchor clamps, to carry out stretching ratio on the TD direction be 1.1 times stretching by increasing the expander spacing jig, carries out drying, imidizate simultaneously under 200 ℃ * 300 seconds, 300 ℃ * 300 seconds, 400 ℃ * 300 seconds, 450 ℃ * 60 seconds condition.Thus, obtaining each thermoplastic polyimide layer is that 4 μ m, high-fire resistance polyimide layer are the bonding film of 17 μ m.

By the bonding film that the method processing identical with record among the embodiment 5 is obtained, make flexible metal-clad laminate both as lamilated body of the present invention.

(embodiment 9)

When being fixed on the stretching of carrying out the TD direction on the expander anchor clamps except the film that will be obtained, making its stretching ratio is outside 1.0 times, makes bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 5.

Calculate and estimate the percent thermal shrinkage of the bonding film that is obtained with above-mentioned formula (1).In addition, calculate and estimate the size changing rate of the flexible metal-clad laminate both that is obtained with above-mentioned formula (2).It the results are shown in the table 2.

(embodiment 10)

When being fixed on the stretching of carrying out the TD direction on the expander anchor clamps except the film that will be obtained, making its stretching ratio is outside 1.0 times, makes bonding film of the present invention and flexible metal-clad laminate both by the order identical with embodiment 8.

Table 2

As shown in table 2, it is little that the result is to use percent thermal shrinkage to be in the size changing rate of the flexible metal-clad laminate both that the bonding film in the prescribed limit makes.

Also have, the present invention is not limited to the situation defined in above each composition, can in the scope shown in the claim, carry out various changes, be also included within the technical scope of the present invention by disclosed respectively technological means among different embodiments or the embodiment being carried out embodiment or embodiment that appropriate combination forms.

As mentioned above, bonding film of the present invention has been stipulated the lower limit of percent thermal shrinkage on the TD direction, has also stipulated the higher limit of percent thermal shrinkage on the MD direction simultaneously.Thus, just can control well the percent thermal shrinkage of bonding film on the whole, therefore under the situation of the lamilated body of having made by laminating (particularly cast coating) metal forming and bonding film laminated, even this lamilated body is applied with the processing processing of heating, also can fully suppress the generation of change in size.

The result just can reach following effect, and for example, the flexible metal-clad laminate both that is inhibited that can manufacturing dimension changes can form fine circuit, thereby just can obtain to adapt to FPCs such as electronics miniaturization, light-weighted FPC.

Therefore, it is the manufacturing field of the various synthetic resins of representative that the present invention not only can be applied to bonding film that contains polyimides or lamilated body, and it is used in the association area that also can expand to this bonding film of use or lamilated body manufacturing electronic device.

Claims

1, bonding film, it is characterized in that possessing the refractory layer that contains the high-fire resistance polyimides and at least one the lip-deep adhesive linkage that contains TPI that is positioned at this refractory layer, percent thermal shrinkage transversely is more than+0.01%, and the percent thermal shrinkage vertically is below-0.02%.

2, the described bonding film of claim 1 is characterized in that above-mentioned bonding film is to form above-mentioned adhesive linkage by coextrusion-curtain coating rubbing method at least one surface of above-mentioned refractory layer to obtain.

3, the described bonding film of claim 1 is characterized in that above-mentioned bonding film is to form above-mentioned adhesive linkage by the gel coating method at least one surface of above-mentioned refractory layer to obtain.

4, each described bonding film in the claim 1～3 it is characterized in that percent thermal shrinkage transversely is more than+0.03%, and the percent thermal shrinkage vertically is below-0.05%.

5, each described bonding film in the claim 1～3 is characterized in that above-mentioned adhesive linkage is formed on two faces of above-mentioned refractory layer.

6, each described bonding film in the claim 1～3 is characterized in that containing in the above-mentioned refractory layer the above non-thermal plasticity polyimide resin as the high-fire resistance polyimides of 90 weight %.

7, each described bonding film in the claim 1～3, tensile modulus of elasticity is in the scope of 5.0～11GPa to it is characterized in that laterally reaching longitudinally.

8, use the lamilated body that each described bonding film is made in the claim 1～3.

9, the described lamilated body of claim 8, it is by forming at bonding film surface laminated metal level.

10, use each described bonding film formed FPC in the claim 1～3.

11, the manufacture method of the described bonding film of claim 2 is characterized in that containing following operation:

To contain as the organic solvent solution of the polyamic acid of high-fire resistance polyimide precursor and, contain the organic solvent solution of TPI or contain organic solvent solution as the polyamic acid of TPI precursor and be provided to simultaneously and have two-layer above extrusion molding with in the extrusion shaping machine of die head, the operation that above-mentioned two kinds of organic solvent solutions are extruded as the membranaceous body of two layers of thin at least and from the outlet of above-mentioned die head

Extrusion molding more than two-layer is expressed on the level and smooth support continuously with above-mentioned two kinds of organic solvent solutions of extruding the die head, make at least a portion volatilization of the organic solvent of the membranaceous body of two layers of thin at least on the above-mentioned support then, obtain having the operation of the laminate film of self-supporting; With

The transverse ends of the laminate film that obtained is fixed, with the stretching ratio that surpass 1.0 times along cross directional stretch on one side carry out the operation of imidizate on one side.

12, the manufacture method of the described bonding film of claim 3 is characterized in that containing following operation:

Thereby make the organic solvent solution that contains as the polyamic acid of high-fire resistance polyimide precursor form the membranaceous gel mould of making gel mould and form operation;

Coating contains the organic solvent solution of TPI or contains as the organic solvent solution of the polyamic acid of TPI precursor and the laminated operation that heats at least one surface of the gel mould that is obtained; With

The transverse ends of the laminate film that obtained is fixed, with the stretching ratio that surpass 1.0 times along cross directional stretch on one side carry out the stretching imidizate operation of imidizate on one side.

13, the manufacture method of FPC, it is characterized in that, be to use the manufacture method of each described bonding film in the claim 1～7 or claim 8 or the formed FPC of 9 described lamilated bodies, wherein metal foil layer be pressed on the bonding film by cast coating.