JPH11300887A - Production of metal foil laminated film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continuously produce a metal foil laminated film good in physical properties with good productivity. SOLUTION: A metal foil laminated film is produced by bonding a multilayered polyimide film having heat fusible polyimide layers and a metal foil to both surfaces of a heat-resistant polyimide layer continuously under heating by at least a pair of pressure members of which the Vickers hardness of 100-1,300.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a metal foil laminated film, and more particularly to a method for producing a multilayer polyimide film having a heat-fusible polyimide layer on both sides of a heat-resistant polyimide layer and a metal foil. The present invention relates to a method for producing a metal foil laminated film, which comprises continuously performing thermocompression bonding with at least a pair of pressing members having a specific hardness in a specific range. According to the present invention, a metal foil laminated film having good physical properties can be continuously obtained with good productivity.

[0002]

2. Description of the Related Art Aromatic polyimide films are widely used for electronic devices such as cameras, personal computers, and liquid crystal displays. In order to use an aromatic polyimide film as a substrate material for a flexible printed board (FPC) or a tape-automated bonding (TAB), a copper foil is laminated using an adhesive such as an epoxy resin. The method has been adopted.

It has been pointed out that aromatic polyimide films are excellent in heat resistance, mechanical strength, electrical properties and the like, but are inferior in properties of polyimide due to poor heat resistance of adhesives. To solve such a problem,
An all-polyimide substrate has been developed in which copper is electroplated on a polyimide film without using an adhesive, a polyamic acid solution is applied to a copper foil, dried and imidized, or a thermoplastic polyimide is thermocompressed. ing.

Further, a polyimide laminate in which a polyimide adhesive is sandwiched between a polyimide film and a metal foil and a method for producing the same are known (US Pat. No. 4,543,295). However, there is a problem that it is difficult to perform this polyimide laminate and its manufacturing method continuously, and that a certain polyimide film has a low peel strength and cannot be used.

Further, a metal foil laminated polyimide film and a method for producing the same are known (Japanese Patent Laid-Open No. 4-33847).
No. JP-A-4-33848). However, in these methods, the take-up speed of the metal foil laminated film when laminating the metal foil and the multilayer polyimide film is 1 m / min or less, which is low in productivity, and wrinkles are generated in the obtained metal foil laminated film. There is a problem that there is a case where

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to use a polyimide and a metal foil of a heat-resistant polyimide as a base layer and a heat-fusible polyimide as a thin layer, and to continuously improve physical properties with good productivity. And to provide a method for producing a metal foil laminated film having a good quality.

[0007]

That is, the present invention provides:
A multi-layer polyimide film having a heat-fusible polyimide layer on both sides of a heat-resistant polyimide layer and a metal foil are continuously thermocompression-bonded with at least one pair of pressurizing members whose surface Vickers hardness is 100-1300. And a method for producing a metal foil laminated film. In addition, the present invention provides a multi-layer polyimide film having a heat-fusible polyimide layer on both sides of a heat-resistant polyimide film and a metal foil, and the metal foil is continuously formed by at least one pair of pressing members having a surface Vickers hardness of 100 to 1300. Metal foil laminated film obtained by subjecting a metal foil laminated film obtained by heat and pressure compression to rolling, etching, and, if necessary, curling, and then cutting to a predetermined size. Related to the production method.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be listed below. 1) The thickness of the heat-resistant polyimide layer is 5 to 150 μm, is 30% or more of the thickness of the multilayer polyimide film, and the thickness (one side) of the heat-fusible polyimide layer is 0.4-1.
A method for producing the above metal foil laminated film having a thickness of 0 μm. 2) The multilayer polyimide film is a co-extruded polyimide film obtained by a co-extrusion-cast film forming method from a heat-resistant polyimide precursor solution as a base layer and a heat-fusible polyimide precursor solution as a thin layer. Production method of metal foil laminated film. 3) The overall coefficient of linear expansion (50-200 ° C.) of the multilayer polyimide film is 10 × 10 ⁻⁶ −25 × 10 ⁻⁶ cm.
/ Cm / ° C. 4) The above-mentioned method for producing a metal foil laminated film in which a multilayer polyimide film and a metal foil are supplied to a pressing member in a rolled state, respectively, and the metal foil laminated film is obtained in a rolled state. 5) The surface Vickers hardness of the pressing member is 200-1000.
The method for producing a metal foil laminated film described above. 6) The method of producing a metal foil laminated film described above, wherein the pressing member is a pair of pressure-bonded metal rolls or a double belt press.

In the present invention, a multilayer polyimide film having a heat-fusible polyimide layer on both sides of a heat-resistant polyimide layer is used. This multilayer polyimide film is
Preferably, a method of obtaining a multilayer polyimide film by laminating a heat-resistant polyimide precursor solution and a heat-fusible polyimide precursor solution by co-extrusion-casting film forming method, drying and imidizing, or the heat resistance described above. A polyimide precursor solution is applied by casting onto a support, and a heat-fusible polyimide precursor solution is applied to both sides of a dried gel film, and dried and imidized to obtain a multilayer polyimide film. . In any of the above methods, it is preferable that the precursor layer of the heat-fusible polyimide is dried and imidized at the maximum heating temperature of 250 to 400 ° C. In particular, a self-supporting film obtained by co-extrusion-casting is preferably dried and imidized at a maximum heating temperature of 250 to 400 ° C.

The heat-resistant polyimide as the base layer of the multilayer polyimide film is preferably 3,3 ', 4,
4'-biphenyltetracarboxylic dianhydride (hereinafter sometimes abbreviated simply as s-BPDA) and paraphenylenediamine (hereinafter sometimes abbreviated simply as PPD).
And optionally 4,4'-diaminodiphenyle-
And TELL (hereinafter may be simply abbreviated as DADE). In this case, the PPD / DADE (molar ratio) is preferably from 100/0 to 85/15. Also,
The heat-resistant polyimide as the base layer is produced from pyromellitic dianhydride, paraphenylenediamine and 4,4'-diaminodiphenyl ether. In this case D
The ADE / PPD (molar ratio) is preferably 90/10/10/90. Further, the heat-resistant polyimide as the base layer includes 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride (BTDA) and pyromellitic dianhydride (PMDA) and paraphenylenediamine (P
PD) and 4,4'-diaminodiphenyl ether (DADE). In this case, BTDA in the acid dianhydride is 20-90 mol%, and PMDA is 10-80 mol%.
Mol%, 30-90 mol% of PPD in diamine, DAD
It is preferred that E is 10-70 mol%.

As the above-mentioned heat-resistant polyimide as the substrate layer, those having a glass transition temperature of 350 ° C. or more and −450 ° C. which cannot be confirmed in the case of a single polyimide film are preferable. 50-200
° C) (MD, TD and any of their averages) is 5
× is intended preferably ^{10 -6 -20 × 10 -6 cm /} cm / ℃. In the synthesis of the base layer polyimide, random polymerization, block polymerization, or synthesis of two kinds of polyamic acids in advance if the proportion of each component is within the above range, and mixing of both polyamic acid solutions, followed by reaction conditions And mixing by any of the methods described above.

Using each of the above components, a substantially equimolar amount of a diamine component and a tetracarboxylic dianhydride are reacted in an organic solvent to obtain a polyamic acid solution (partly if a uniform solution state is maintained). May be imidized).
Other aromatic tetracarboxylic dianhydride or aromatic diamine of the kind and amount that does not impair the physical properties of the substrate layer polyimide,
For example, 4,4'-diaminodiphenylmethane or the like may be used.

In the present invention, the heat-fusible polyimide as a thin layer is preferably 1,3-bis (4-aminophenoxybenzene) (hereinafter sometimes abbreviated as TPER), 2,3,3. 3 ', 4'-biphenyltetracarboxylic dianhydride (hereinafter sometimes abbreviated as a-BPDA). As the heat-fusible polyimide as the thin layer, 1,3-bis (4-aminophenoxy) -2,2-dimethylpropane (DAN)
PG) and 4,4'-oxydiphthalic dianhydride (ODP)
A) and a-BPDA. Or,
It is produced from 4,4'-oxydiphthalic dianhydride (ODPA) and pyromellitic dianhydride and 1,3-bis (4-aminophenoxybenzene).

The above heat-fusible polyimide is obtained by mixing the above-mentioned components and, if necessary, other tetracarboxylic dianhydrides and other diamines in an organic solvent at a temperature of about 100 ° C. or less.
In particular, the solution is reacted at a temperature of 20 to 60 ° C. to form a solution of polyamic acid, and the solution of polyamic acid is used as a dope solution, a thin film of the dope solution is formed, and the solvent is removed from the thin film by evaporating the solvent. And imide cyclization of the polyamic acid.

Further, the solution of the polyamic acid prepared as described above is heated to 150 to 250 ° C. or 150 ° C. or less, particularly 15 to 50 ° C. by adding an imidizing agent.
And then evaporate the solvent after imide cyclization or precipitate in a poor solvent to form a powder, and then dissolve the powder in an organic solution to obtain a heat-fusible polyimide organic solvent solution. be able to.

In the present invention, other tetracarboxylic dianhydrides, for example, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,2- Bis (3,4-dicarboxyphenyl)
Propane dianhydride or 2,3,6,7-naphthalenetetracarboxylic dianhydride such as 3,3 ′,
It may be replaced by 4,4'-biphenyltetracarboxylic dianhydride. In addition, other diamines such as 4,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, 4,4′-diaminodiphenylmethane, and 2,2 may be used as long as the physical properties of the heat-fusible polyimide are not impaired.
-Bis (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, 2,2-bis Flexible aromatic diamines having a plurality of benzene rings such as [4- (4-aminophenoxy) phenyl] hexafluoropropane;
-Diaminobutane, 1,6-diaminohexane, 1,8
-Diaminooctane, 1,10-diaminodecane, 1,
It may be replaced by an aliphatic diamine such as 12-diaminododecane, or a diaminodisiloxane such as bis (3-aminopropyl) tetramethyldisiloxane. The proportion of the other aromatic diamine used is preferably 20 mol% or less, particularly preferably 10 mol% or less based on the total diamine. The proportion of the aliphatic diamine and diaminodisiloxane used is preferably 20 mol% or less based on the total diamine. Exceeding this ratio lowers the heat resistance of the heat-fusible polyimide. Dicarboxylic anhydrides, such as phthalic anhydride and its substitution, hexahydrophthalic anhydride and its substitution, succinic anhydride and its substitution, and the like, in order to block the amine terminal of the heat-fusible polyimide. Phthalic anhydride may be used.

In order to obtain the heat-fusible polyimide according to the present invention, the amount of the diamine (as the number of moles of amino group) used in the above-mentioned organic solvent is the total number of moles of the acid anhydride (to the amount of tetraacid dianhydride). (Total moles of dicarboxylic anhydride as anhydride groups), preferably 0.92
To 1.1, particularly 0.98 to 1.1, especially 0.99 to 1.1, and the amount of the dicarboxylic anhydride used is based on the molar amount of the acid anhydride group of the tetracarboxylic dianhydride. The ratio is preferably 0.05 or less, particularly 0.000.
It is preferable to react each component at a ratio of 1 to 0.02.

When the use ratio of the diamine and dicarboxylic anhydride is out of the above range, the molecular weight of the obtained polyamic acid, that is, the heat-fusible polyimide is small,
This results in a decrease in the peel strength of the metal foil laminated film. Further, for the purpose of restricting the gelling of the polyamic acid, a phosphorus-based stabilizer such as triphenyl phosphite, triphenyl phosphate or the like is used in an amount of 0.01 to 0.01% based on the solid content (polymer) concentration at the time of polyamic acid polymerization. It can be added in the range of 1%. Further, a basic organic compound can be added to the dope solution for the purpose of accelerating imidization. For example,
Imidazole, 2-imidazole, 1,2-dimethylimidazole, 2-phenylimidazole, etc. in an amount of 0.05 to 10% by weight, especially 0.1 to 2% by weight of the polyamic acid;
It can be used in proportions by weight. Since these form a polyimide film at a relatively low temperature, they are used to avoid insufficient imidization. In addition, for the purpose of stabilizing the thermocompression bonding strength, a heat-fusible polyimide raw material dope was used.
An organic aluminum compound, an inorganic aluminum compound or an organic tin compound may be added to the mold. For example, aluminum hydroxide, aluminum triacetylacetonate or the like is used as an aluminum metal for polyamic acid.
It can be added at a ratio of at least ppm, especially 1-1000 ppm.

The organic solvent used for the production of the polyamic acid is N-methyl-2-pyrrolidone, N,
N-dimethylformamide, N, N-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 multilayer polyimide film of the present invention, for example, the above-mentioned polyamic acid solution of the heat-resistant polyimide for the base layer and the solution of the heat-fusible polyimide or its precursor for the thin layer are co-extruded and Cast on a support surface such as a stainless steel mirror surface, belt surface, etc.
It is preferable to set the semi-cured state at 0 to 200 ° C. or the dried state before that. Treating a cast film at a high temperature exceeding 200 ° C. tends to cause defects such as a decrease in adhesiveness in the production of a multilayer polyimide film.
The semi-cured state or a state before that means that it is in a self-supporting state by heating and / or chemical imidization.

The co-extrusion of the polyamic acid solution for providing the base layer polyimide with the polyamic acid solution or the polyimide solution for providing the heat-fusible polyimide is described in, for example, Japanese Patent Application Laid-Open No. 3-180343 (Japanese Patent Publication No.
No. 102661), it can be supplied to a three-layer extrusion molding die by a coextrusion method and cast on a support. On both sides of the extruded material layer for providing the base layer polyimide, a polyamic acid solution or a polyimide solution for providing a heat-fusible polyimide is laminated to form a multilayer film-like material, and then dried. Heating to a temperature below the transition temperature (Tg) and below the temperature at which degradation occurs, preferably 250-400 ° C. (surface temperature measured by a surface thermometer) (preferably heating at this temperature for 1 to 60 minutes) Dried) and imidized,
A multilayer extruded polyimide film having a heat-fusible polyimide on both sides of the substrate layer polyimide can be produced.

The heat-fusible polyimide according to the present invention comprises:
By using the acid component and the diamine component, the glass transition temperature is 200 to 250 ° C., and the gelation of the heat-fusible polyimide is substantially performed by drying / imidizing under the above conditions. It does not melt at a temperature in the range of not less than the glass transition temperature and about 300 ° C. or less, which is achieved by not causing the elastic modulus (the elastic modulus at 275 ° C. is usually 0.001 of the elastic modulus at room temperature. (Approximately 0.5 times).

In the present invention, the thickness of the polyimide film (layer) of the base layer is preferably 5 to 150 μm. If the thickness is less than 5 μm, problems arise in mechanical strength and dimensional stability of the formed multilayer polyimide film. Also 150
When the thickness is more than μm, it is not preferable because there are difficulties in removing the solvent and imidizing. In the present invention, the thickness of the heat-fusible polyimide (Y) layer is preferably 0.4 to 10 μm, particularly preferably 1 to 10 μm. If it is less than 0.4 μm, the adhesive performance is reduced, and if it exceeds 10 μm, it can be used, but there is no particular effect, but rather the heat resistance and productivity of the metal foil laminated film are undesirably reduced. The thickness of the polyimide film (layer) of the substrate layer is 3 times that of the entire multilayer film.
It is preferably 0% or more. If the ratio is smaller than this, the coefficient of linear thermal expansion of the formed multilayer film becomes large, and problems such as mechanical strength and dimensional stability occur.

By the above-mentioned co-extrusion-casting film forming method, the polyimide of the base layer and the heat-fusible polyimide on both sides thereof can be cured at a relatively low temperature. The imidization and drying of the multilayer polyimide film can be completed without coming. The multilayer polyimide film in the present invention preferably has a coefficient of linear thermal expansion (50-200 ° C.) (all of MD, TD and average) of 10 × 10 ⁻⁶ −25 × 10 ⁻⁶ cm / cm / ° C.

Examples of the metal foil used in the present invention include various metal foils such as copper, aluminum, gold and alloy foils, and preferably rolled copper and electrolytic copper. As the metal foil, a metal foil having a small surface roughness, preferably having an Rz of 7 μm or less, particularly preferably an Rz of 5 μm or less is preferable. Such a metal foil, for example, a copper foil, is known as VLP, LP (or HTE). The thickness of the metal foil is not particularly limited, but is preferably 5 to 60 μm, particularly preferably 10 to 20 μm.

In the present invention, a multi-layer polyimide film having a heat-fusible polyimide layer on both sides of the above-mentioned heat-resistant polyimide layer and a metal foil are provided with a surface Vickers hardness of 100-1300, preferably 200-1000. The metal foil laminated film is pressed by heating at a temperature of at least 30 ° C. and at most 400 ° C. below the glass transition temperature of the heat-fusible polyimide continuously with at least one pair of pressing members. To manufacture. Examples of such a pressing member include a pair of pressure-bonded metal rolls or a double belt press (the pressure-bonded portion may be made of metal or ceramic sprayed metal). The Vickers hardness is indicated as HV100 or HV1300 in the case of metal or ceramic sprayed metal. In the present invention, by using a pressing member having the above surface hardness, preferably a metal roll or a double belt press, and combining the above-mentioned multilayer polyimide film and a metal foil, the material is continuously heated. By pressing, a metal foil laminated film having good physical properties can be manufactured at a take-up speed of 2 m / min or more, particularly 3 m / min or more.

The method of the present invention is particularly useful when the multi-layer polyimide film and the metal foil are supplied to the pressing member in a roll-wound state, and the metal foil laminated film is obtained in a roll-wound state. It is suitable.

In the method of the present invention, for example, after the metal foil laminated film obtained as described above is subjected to roll winding, etching, and, if necessary, curl return treatment, it is reduced to a predetermined size. Disconnect and apply.

[0029]

The present invention will be described below in more detail with reference to examples and comparative examples. In each of the following examples, parts mean parts by weight. In each of the following examples, the evaluation of physical properties and the peel strength of the copper foil laminated film were measured according to the following methods. Vickers hardness: Coefficient of linear thermal expansion: Measured at 20-200 ° C, 5 ° C / min (T
D, MD, average value), cm / cm / ° C. Peel strength of copper foil laminated film: 90 ° peel strength was measured. Solder heat resistance: Observing and evaluating the appearance after immersion at 280 ° C. for 1 minute Appearance: Observing and evaluating the appearance of the copper foil surface of the copper foil laminated film, including the presence or absence of wrinkles, ○: good, Δ: slightly poor, ×: Bad

Synthesis Example 1 of Dope for Producing Substrate Layer Polyimide A reaction vessel equipped with a stirrer and a nitrogen inlet tube was charged with N-methyl-
2-Pyrrolidone was added, and paraphenylenediamine (PPD) and 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA) were further added at 1000: 9.
At a molar ratio of 98, the monomer concentration was 18% (% by weight, the same applies hereinafter). After completion of the addition, the reaction was continued for 3 hours while maintaining the temperature at 50 ° C. The obtained polyamic acid solution is a brown viscous liquid, and the solution viscosity at 25 ° C. is about 15
It was 00 poise. This solution was used as a dope.

Synthesis of Dope for Polyimide Production for Thin Layer-1 N-Methyl-2-pyrrolidone was added to a reaction vessel equipped with a stirrer and a nitrogen inlet tube, and 1,3-bis (4-
Aminophenoxy) benzene (TPE-R) and 2,3
3 ', 4'-biphenyltetracarboxylic dianhydride (a
-BPDA) in a molar ratio of 1000: 1000 to give a monomer concentration of 22%, and triphenyl phosphate was added in an amount of 0.1% by weight of the monomer. After completion of the addition, the reaction was continued for 1 hour while maintaining the temperature at 25 ° C. To this polyamic acid solution was added 10% of toluene with respect to N-methyl-2-pyrrolidone, and the reaction temperature was increased to 190 ° C.
And the formed water is distilled off together with toluene.
Reaction was carried out for a time to obtain a yellow-red viscous polyimide solution. 25 ° C
Was about 2000 poise. This solution (dope) is referred to as Y-1.

Synthesis of Dope for Producing Thin Layer Polyimide-2 N, N-dimethylacetamide (DMAC) was added to a reaction vessel equipped with a stirrer and a nitrogen inlet tube.
3-bis (4-aminophenoxy) -2,2-dimethylpropane was added, and finally 4,4'-oxydiphthalic dianhydride was added at a molar ratio of 1000: 1000 to give a monomer concentration of 22%. Triphenyl phosphate and 2-imidazole were each added in an amount of 0.1 to the weight of the monomer.
1% was added. After completion of the addition, the reaction was continued at 25 ° C. for 5 hours,
A light yellow-brown viscous polyamic acid solution was obtained. The solution viscosity at 25 ° C. was about 2000 poise. This solution (dope) is referred to as Y-2.

Comparative Example 1-2 A three-layer extrusion molding die (multi-manifold die) was prepared by synthesizing the base layer dope of Synthesis Example 1 and the thin layer polyimide dope (Dop Y-1). ) Was used to cast the polyamic acid solution from a three-layer extrusion die onto a metal support, and was 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 a long three-layer extruded polyimide film is wound up and wound on a roll. I took it. The obtained 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., and TD:
19 ppm / ° C, average: 21 ppm / ° C, the glass transition temperature of the base layer polyimide was not confirmed at a temperature of 450 ° C or less, and the glass transition temperature of the thin layer polyimide was 250 ° C.
And no substantial gelation occurred. This three-layer extruded polyimide film and two rolled electrolytic copper foils (CF-T9, V
LP, Rz of about 4 μm, thickness of 18 μm) using a roll of a roll material shown in Table 1 under continuous heating under the conditions shown in Table 1 to form a copper foil laminated film. It was wound up on a take-up roll. All operations are performed in air.
Cooling was performed by natural cooling. Table 2 shows the evaluation results of the obtained copper foil laminated films.

Example 1-3 The same procedure as in Comparative Example 1 was carried out except that the kind of the pressure roll and the pressure conditions were changed as shown in Table 1. Table 2 shows the evaluation results of the obtained copper foil laminated films.

Example 4 A three-layer extrusion molding die (multi-manifold type die) of the substrate layer dope of Synthesis Example 1 and the polyimide thinning dope (Dop Y-2) was prepared. Using the film forming apparatus provided, the polyamic acid solution was cast from a three-layer extrusion die onto a metal support and dried continuously 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 180 ° C. to 350 ° C. in a heating furnace to remove the solvent and imidize, and a long three-layer extruded polyimide film is wound up and wound on a roll. I took it. The obtained 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: 14 ppm / ° C., and TD:
13 ppm / ° C., average: 14 ppm / ° C., the glass transition temperature of the polyimide layer of the base layer was not confirmed below 450 ° C., and the thin-layer polyimide had a glass transition temperature of 219 ° C., and gelation substantially occurred. Did not. The same procedure as in Example 2 was carried out except that this three-layer extruded polyimide film was used, and the metal foil laminated film was taken up on a take-up roll. Table 2 shows the evaluation results of the obtained copper foil laminated films.

Example 5 The molding die (multi-manifold type die) was changed.
A long three-layer extruded polyimide film having a thickness of 58 μm was wound on a take-up roll in the same manner as in Comparative Example 1 except that the maximum heating temperature and the heating time were changed to 320 ° C. and 3 minutes. The obtained three-layer extruded polyimide film has a thickness of each layer of 8 μm / 42 μm / 8 μm, a coefficient of linear expansion (50-200 ° C.) of MD: 25 ppm / ° C., T
D: 21 ppm / ° C., average: 23 ppm / ° C., no glass transition temperature of the base layer polyimide was confirmed, and the glass transition temperature of the thin layer polyimide was 250 ° C. The same procedure as in Example 2 was carried out except that this three-layer extruded polyimide film was used, and a copper foil laminated film was taken up on a take-up roll. Table 2 shows the evaluation results of the obtained copper foil laminated films.

[0037]

[Table 1]

[0038]

[Table 2]

Example 6 Two sets of heating rolls (material: metal,
HV about 600) Using a double belt press consisting of two sets and an endless metal belt rotating around them, continuously press-bond at a roll part temperature of 350 ° C and a winding speed of 5 m / min to wind a copper foil laminated film. Take up on a take-up roll. The obtained copper foil laminated film is equivalent to the copper foil laminated film obtained in Example 1.

Example 7 After the copper foil laminated film obtained in Example 1-5 was subjected to an etching treatment by a conventional method, it was cut into a predetermined size by using a mold, and was uniformly cut into a size of 500 mm × 500 mm. A thick copper foil circuit board was obtained. Each of these copper foil circuit boards had good soldering heat resistance (280 ° C., 1 minute) and did not warp.

[0041]

According to the present invention, the following effects can be obtained because of the above configuration.

According to the present invention, continuously with good productivity,
A metal foil laminated film having good physical properties can be obtained.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B32B 31/30 B32B 31/30 // H05K 1/03 610 H05K 1/03 610N 630 630D B29K 77:00 B29L 7:00 9: 00

Claims (8)

[Claims] 1. A multi-layer polyimide film having a heat-fusible polyimide layer on both sides of a heat-resistant polyimide layer and a metal foil are continuously formed with at least one pair of pressing members having a surface Vickers hardness of 100-1300. A method for producing a metal foil laminated film, characterized in that the film is pressure-bonded under heating. 2. The heat-resistant polyimide layer has a thickness of 5-15.
0 μm and 30% of the thickness of the multilayer polyimide film
The method for producing a metal foil laminated film according to claim 1, wherein the thickness (one side) of the heat-fusible polyimide layer is 0.4 to 10 µm. 3. A multi-layer polyimide film is co-extruded from a heat-resistant polyimide precursor solution as a base layer and a heat-fusible polyimide or a precursor solution thereof as a thin layer by co-extrusion obtained by a casting film forming method. The method for producing a metal foil laminated film according to claim 1, which is a polyimide film. 4. The multilayer polyimide film as a whole has a coefficient of linear expansion (50-200 ° C.) of 10 × 10 ^-6 -25 ×
The method for producing a metal foil laminated film according to claim 1, wherein the temperature is 10 ^-6 cm / cm / ° C. 5. A multi-layer polyimide film and a metal foil are supplied to a pressing member in a roll-wound state, respectively.
The method for producing a metal foil laminated film according to claim 1, wherein the metal foil laminated film is obtained in a roll-wound state. 6. The pressing member has a surface Vickers hardness of 200.
The method for producing a metal foil laminated film according to claim 1, which is -1000. 7. The method for producing a metal foil laminated film according to claim 1, wherein the pressing member is a pair of press-bonded metal rolls or a double belt press. 8. A multi-layer polyimide film having a heat-fusible polyimide layer on both sides of a heat-resistant polyimide film and a metal foil, and having a surface Vickers hardness of 100-1300.
After the metal foil laminated film obtained by continuous pressure bonding under heating with at least one pair of pressing members is subjected to roll winding, etching, and, if necessary, curl return processing, A method for producing a metal foil laminated film that is cut into pieces.