JP3912611B2 - Metalized polyimide film, metalized polyimide film roll, and flexible printed wiring board - Google Patents

Description

  The present invention relates to a conductive polyimide film and a film roll used for electronic devices, flexible printed wiring boards and the like that reduce the size and weight of components. More specifically, the present invention relates to a conductive polyimide film for the flexible printed circuit board used in TAB, COF, PGA and the like in semiconductor packaging and the like. More particularly, the present invention relates to a conductive polyimide film having a specific performance polyimide film as a base film, and the conductive polyimide film after conductivity is less warped and curled.

Conventionally, a metallized polyimide film used for a so-called bonded type flexible printed wiring board in which a metal foil such as a copper foil or an aluminum foil is bonded to a polyimide film with an adhesive is known. This has the following problems considered to be caused by the adhesive used.
First, there are drawbacks in that the dimensional accuracy is lowered due to inferior thermal performance than the film, and the electrical characteristics are deteriorated due to impurity ion contamination, and there is a limit to high-density wiring. In addition, there is a disadvantage that the workability such as the thickness of the adhesive layer and the drilling of a double-sided hole is lowered. Therefore, it can be said that there are many inconvenient points for reducing the size and weight.
On the other hand, a flexible printed wiring board without a so-called thin film type adhesive layer in which a metal layer is formed on a polyimide film by a dry plating method such as vacuum deposition, sputtering, ion plating, and CVD without using an adhesive. Conductive (metallized) polyimide films have been proposed.

For example, a flexible electric circuit carrier in which a chromium-based ceramic vapor deposition layer, a copper or copper alloy vapor deposition layer, and a copper plating layer are sequentially provided on an insulating film has been proposed (see Patent Document 1). In addition, a metal-film laminate manufacturing method has been proposed in which a metal oxide by plasma is randomly arranged on a polymer film, and then a metal vapor deposition layer and a metal plating layer are provided (see Patent Document 2). Further, a chromium / chromium oxide sputtering layer having a thickness of 25 to 150 Å is provided on the electrically insulating support film, and a copper sputtering layer having a thickness of less than 1 μm is applied, and a photoresist composition is applied to the copper layer. A method of manufacturing a circuit material has been proposed (see Patent Document 3).
As can be seen from these examples, the conventional thin film type metallized polyimide film is produced by first forming some base layer on the polyimide film and then forming copper as a good conductive material thereon. . There is no chemical bonding force between the metal layer that is the conductive layer and the polyimide film that is the base material, and a micro underlayer is cast on the surface of the base material, while copper is a metal / metal. By bonding, an adhesive force is expressed through the base layer.
When a non-metal or metal oxide is used for the underlayer, it is difficult to remove the underlayer by etching, and the metal oxide left between the lines due to the reducing action in the electroless plating process, etc. May be reduced and become a conductive metal foreign matter, resulting in poor insulation between wires.
Japanese Patent Laid-Open No. 04-329690 JP 04-290742 A Japanese Patent Application Laid-Open No. Sho 62-293689

Further, chromium oxide often used as an underlayer is considered to be an unfavorable compound for environmental hygiene. When a metal other than copper is used for the underlayer, it becomes a problem whether the underlayer can be removed with a copper etching solution. If a metal having better corrosion resistance than copper is used, the removal of the underlying metal becomes insufficient, and the insulation between the lines may be lowered. In the case of a metal that is easier to etch than copper, the underlying portion is easily over-etched, and the effective adhesive strength of the conductor is likely to be reduced. Furthermore, even if the lowering of the insulation property due to the base metal itself is not a problem, the metal remaining during the electroless plating in the subsequent process shows catalytic activity, and the plated metal may be deposited between the lines to cause a short circuit. is there. Furthermore, there is a concern that the base material remaining between the wirings may deteriorate the migration resistance between the wirings.
From this point of view, in recent years, metalized polyimide films using nickel-chromium-based alloys as a base have attracted attention, and nickel-chromium-based alloy layers are used as base layers for general polyimide films, and further thickened with copper. There is an example of a metallized film (see, for example, Patent Document 4).
JP 2002-252257 A

Further, as a polyimide film, from a polyimide having 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, p-phenylenediamine, and p-diaminodiphenyl ether (4,4′-oxydianiline) in the main chain as acidic components. A polyimide long film is proposed (see Patent Document 5). Obtained by polymerization and dehydration using biphenyltetracarboxylic dianhydride and / or pyromellitic dianhydride as the aromatic tetracarboxylic acid component and p-phenylenediamine and / or diaminodiphenyl ether as the aromatic diamine component. A long polyimide film has also been proposed (see Patent Document 6).
JP 09-328544 A JP 09-188863 A

Moreover, the polyimide benzoxazole film which consists of a polyimide which has a benzoxazole ring in a principal chain is proposed as a polyimide long film with a high elasticity modulus (refer patent document 7).
Furthermore, a polyimide long film with little curling at 25 ° C. is proposed by setting the orientation ratio of the polyimide long film to the predetermined value or less (see Patent Document 8).
Japanese Patent Laid-Open No. 06-056792 JP 2000-085007 A

The use of a base film made of a conventionally known polyimide film or polyimide benzoxazole film is inferior to the use of a base material made of ceramic, and warpage and distortion are likely to occur when electronic parts are produced due to physical property differences in the film. There was a problem. In order to eliminate the warp and distortion of the film, measures have been taken to reduce the apparent warp of the film by heat treatment under stretching. However, even if the apparent warpage of the film, that is, the manifested warpage of the film, can be eliminated, it is necessary to process at a high temperature particularly when applied as an electronic component. The problem that the existing strain becomes obvious and the curling occurs has not been solved. Therefore, even if the film has a small apparent warp, a film in which curling occurs during processing leads to a decrease in production yield, and it is often difficult to obtain high-quality electronic components.
Furthermore, an important issue along with the development of curl due to high-temperature treatment is the problem of the uniformity in the longitudinal direction of the film. That is, even if there is a potential internal strain locally, the production yield of the film is reduced.
The present invention is a conductive film using a polyimide film excellent in flatness and homogeneity suitable as a base material for electronic components, and having excellent heat resistance with little warping and curling even when subjected to high temperature treatment, and An object is to provide a film roll.

As a result of intensive studies, the present inventors have used a polyimide film having a curl degree of 10% or less at a specific 300 ° C. as a base film such as an FPC (Flexible Printed Circuit Board), TAB tape, or COF tape film. At that time, it was found that high-quality and uniform FPC (flexible printed wiring board), TAB tape, and COF tape film were obtained, and the present invention was completed.
That is, this invention consists of the following structures.
1. A polyimide film obtained by reacting an aromatic diamine and an aromatic tetracarboxylic acid, wherein the polyimide is at least a residue of a pyromellitic acid residue as a residue of an aromatic tetracarboxylic acid and a residue of an aromatic diamine A film having a diaminodiphenyl ether residue and obtained by drying a coating film under a condition where the atmospheric temperature on the opposite side is 1 to 55 ° C. higher than the atmospheric temperature on the upper side of the coating film on the support in the drying step . A metallized polyimide film comprising a polyimide film having a curl degree of 10% or less after heat treatment at 300 ° C. as a base film, and a metal thin film layer formed on at least one side of the base film.
2. 2. The metallized polyimide film as described in 1 above, wherein the curl degree after heat treatment at 300 ° C. of the film is 8% or less.
3. 3. The metallized polyimide film according to 1 or 2 above, further having a biphenyltetracarboxylic acid residue as an aromatic tetracarboxylic acid residue and a p-phenylenediamine residue as an aromatic diamine residue. .
4). 4. The metallized polyimide film as described in any one of 1 to 3 above, wherein the metal thin film layer is formed by a dry plating method.
5. 5. The metallized polyimide film as described in any one of 1 to 4 above, wherein a metal thin film layer is formed on at least one surface of the base film via an underlayer.
6). 6. A metallized polyimide film, wherein a thick metal layer is further laminated on the metal thin film layer according to any one of 1 to 5 above.
7). 7. The metallized polyimide film as described in 6 above, wherein the thick metal layer is formed by a wet plating method.
8). A solution comprising at least a pyromellitic acid residue as an aromatic tetracarboxylic acid residue and a diaminodiphenyl ether residue as a residue of an aromatic diamine and a solvent is formed on the support, and then on the support. The coating film is dried under the condition that the atmospheric temperature on the opposite side is 1 to 55 ° C. higher than the atmospheric temperature on the upper side of the coating film, and then subjected to heat treatment to form a polyimide film. A method for producing a metallized polyimide film, comprising forming a metal thin film layer on at least one surface of a material film.
9. 8. A flexible printed wiring board obtained by partially removing a metal layer of the metallized polyimide film according to any one of 1 to 7 above.
10. A flexible printed wiring board, wherein a semiconductor chip is directly mounted on the flexible printed wiring board according to 9 above.
11. A polyimide film obtained by reacting an aromatic diamine with an aromatic tetracarboxylic acid, wherein the polyimide is at least a residue of an aromatic tetracarboxylic acid, a biphenyltetracarboxylic acid residue, a residue of an aromatic diamine From the polyimide film obtained by drying the coating film under a condition where the atmospheric temperature on the opposite side is 1 to 55 ° C. higher than the atmospheric temperature on the upper side of the coating film on the support in the drying step having a phenylenediamine residue as A polyimide film having a degree of curl after heat treatment at 300 ° C. of the film of 10% or less and a coefficient of variation (CV%) of the linear expansion coefficient of the film of 25% or less is used as the substrate film, A metallized polyimide film roll comprising a metal thin film layer formed on at least one surface of a film
12 12. The metallized polyimide film roll as described in 11 above, wherein the difference between the maximum value and the minimum value of the degree of warpage at each part is 5% or less.
13. 13. The metallized polyimide film roll as described in any one of 11 or 12 above, wherein the metal thin film layer is formed by a dry plating method.
14 14. The metallized polyimide film roll according to any one of the above 11 to 13, wherein a metal thin film layer is formed on at least one surface of the base film via an underlayer.
15. A metallized polyimide film roll, wherein a thick metal film layer is further laminated on the metal thin film layer according to any one of 11 to 14 above.
16. 16. The metallized polyimide film roll as described in 15 above, wherein the thick film metal layer is formed by a wet plating method.

For example, in a printed wiring board, a metallized film using the polyimide film in the present invention as a base film is formed with a metal thin film layer and a metal thick film layer on one or both sides of the polyimide film. A wiring pattern having a thickness of about 30 μm, a line spacing of 5 to 30 μm, and a thickness of about 3 to 40 μm is formed. The base film is subjected to vapor deposition, sputtering, other heat treatment, and chemical treatment when forming the metal thin film layer. In most cases, one side is first subjected to these treatments during various treatments, especially when the difference in physical properties of the front and back surfaces of the polyimide film, particularly when the curl degree after heat treatment at 300 ° C. of the film is below a certain level, On the other hand, the polyimide film hardly warps or distorts, and as a result, the quality of the obtained printed wiring board is improved. And the yield is also improved, also be obtained by maintaining planarity, which results improved these products yield for subsequent high temperature processing such as annealing and soldering receive and these printed circuit boards.
In this way, the polyimide film as a heat resistant film is often exposed to heat, and the low curl degree after 300 ° C. heat treatment of the film against the heat is extremely important when used as a base material for industrial products. Quality.
The metalized polyimide film using the specific polyimide film of the present invention is used as an electronic component exposed to high temperature, and the base material is less likely to warp or distort during production, and high-quality electronic component production and yield improvement are achieved. Can be realized and is extremely meaningful in industry.

  The base film in the metallized polyimide film of the present invention is a polyimide film obtained by reacting an aromatic diamine and an aromatic tetracarboxylic acid, and the polyimide is at least as a residue of the aromatic tetracarboxylic acid. The first characteristic is that it has a diaminodiphenyl ether residue as a merit acid residue and an aromatic diamine residue, and the curl degree after heat treatment at 300 ° C. of the film is 10% or less.

In the present invention, the degree of curl of a polyimide film at 300 ° C. means the degree of deformation in the thickness direction relative to the surface direction of the film after performing a predetermined heat treatment, and specifically, shown in FIG. As described above, after a 50 mm × 50 mm test piece was treated with hot air at 300 ° C. for 10 minutes, the test piece was left on the plane so as to be concave, and the distances from the four corner planes (h1, h2, h3, h4) : The average value of unit mm) is a curl amount (mm), and is a value expressed as a percentage (%) of the curl amount with respect to the distance (35.36 mm) from each vertex to the center of the test piece.
The sample piece had a length pitch of 1/5 with respect to the polyimide film, and 2 points in the width direction (1/3 and 2/3 points of the width length), with n = 10 in total 10 The points are sampled (when it cannot be taken, sampling is performed with a maximum of n points), and the measured value is an average value of 10 points (or n).
Specifically, it is calculated by the following formula.
Curling amount (mm) = (h1 + h2 + h3 + h4) / 4
Curling degree (%) = 100 × (curl amount) /35.36
In the present invention, the curl degree after the heat treatment at 300 ° C. is more preferably 8% or less, and further preferably 5% or less.
When it exceeds 10%, when manufacturing an electronic component based on the polyimide film according to the present invention (especially, a step of soldering an electronic member to be processed at a high temperature), the distortion inherent in the film is developed and curling occurs. This may cause problems such as misalignment and floating of the electronic member, and may cause problems in assembly with the housing and connector connection.

In the present invention, a pyromellitic acid residue is a pyromellitic acid that is formed by a reaction with an aromatic diamine from a functional derivative such as pyromellitic acid and an anhydride or halide. It refers to a residue derived from merit acid. The diaminodiphenyl ether residue refers to a residue derived from diaminodiphenyl ether in a bond in polyamic acid or polyimide formed by reaction of diaminodiphenyl ether and aromatic tetracarboxylic acids from various derivatives thereof.
Hereinafter, in the present invention, other aromatic tetracarboxylic acid residues and other aromatic diamine residues have the same meaning.

The polyimide film as the base material of the present invention comprises a polyimide obtained by reacting an aromatic diamine and an aromatic tetracarboxylic acid, and the polyimide is pyromellitic acid as a residue of at least the aromatic tetracarboxylic acid. It has a diaminodiphenyl ether residue as a residue or a residue of an aromatic diamine.
In the above-mentioned “reaction”, first, aromatic diamines and aromatic tetracarboxylic acids are subjected to a ring-opening polyaddition reaction or the like in a solvent to obtain an aromatic polyamic acid solution, and then the aromatic polyamic acid solution. After forming a green film from the above, it is performed by high-temperature heat treatment or dehydration condensation (imidization).

The aromatic polyamic acid is a substance composed of the above aromatic tetracarboxylic acids (collectively referred to as acids, anhydrides and functional derivatives, hereinafter also referred to as aromatic tetracarboxylic acids) and aromatic diamines (hereinafter also referred to as aromatic diamines). In particular, an equimolar amount is preferably produced by reacting and polymerizing in an inert organic solvent at a polymerization temperature of 90 ° C. or less for 1 minute to several days. The aromatic tetracarboxylic acid and the aromatic diamine may be added to the organic solvent as a mixture or as a solution, or an organic solvent may be added to the above components. The organic solvent may dissolve some or all of the polymerization components and preferably dissolves the copolyamic acid polymer.
Preferred solvents include N, N-dimethylformamide and N, N-dimethylacetamide. Other useful compounds of this type are N, N-diethylformamide and N, N-diethylacetamide. Other solvents that can be used are dimethyl sulfoxide, N-methyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone and the like. Solvents can be used alone or in combination with each other or with poor solvents such as benzene, benzonitrile, dioxane and the like.
The amount of solvent used is preferably in the range of 75-90% by weight of the aromatic polyamic acid solution, since this concentration range gives the optimum molecular weight. The aromatic tetracarboxylic acid and the aromatic diamine component need not be used in absolute equimolar amounts. In order to adjust the molecular weight, the molar ratio of aromatic tetracarboxylic acid: aromatic diamine is in the range of 0.90 to 1.10.
The aromatic polyamic acid solution produced as described above contains 5 to 40% by mass, preferably 10 to 25% by mass of the polyamic acid polymer.

In the present invention, among these aromatic diamines, diaminodiphenyl ether is a preferred diamine. Specific examples of diaminodiphenyl ether include 4,4′-diaminodiphenyl ether (DADE), 3,3′-diaminodiphenyl ether and 3,4′-diaminodiphenyl ether.
In a preferred embodiment, in addition to these diaminodiphenyl ethers, phenylenediamines, preferably p-phenylenediamine, can be used. Furthermore, in addition to these aromatic diamines, other aromatic diamines may be appropriately selected and used.
In the present invention, among the aromatic tetracarboxylic acids, pyromellitic acids (pyromellitic acid and its dianhydride (PMDA) and lower alcohol esters thereof) are preferable.
As a preferred embodiment, biphenyltetracarboxylic acids, preferably 3,3 ′, 4,4′-biphenyltetracarboxylic acids can be used in addition to pyromellitic acid. Furthermore, in addition to these aromatic tetracarboxylic acids, other aromatic tetracarboxylic acids may be appropriately selected and used.
In the present invention, diaminodiphenyl ethers are 50 to 100 mol% based on the total aromatic diamines, phenylenediamines are 0 to 50 mol% based on the total aromatic diamines, and other aromatic diamines other than the former two. It is preferable to use 0 to 50 mol% of all aromatic diamines. When the mole% ratio exceeds this range, the balance as a heat-resistant polyimide film such as flexibility, rigidity, strength, elastic modulus water absorption, hygroscopic expansion coefficient, and elongation is lost.

  In the present invention, pyromellitic anhydride is 50 to 100 mol% based on the total aromatic tetracarboxylic acid, and biphenyltetracarboxylic acid, preferably 3,3 ′, 4,4′-biphenyltetracarboxylic anhydride is fully aromatic. It is preferable to use 0 to 50 mol% with respect to the aromatic tetracarboxylic acids and use 0 to 50 mol% of the other aromatic tetracarboxylic acids with respect to the total aromatic tetracarboxylic acids. When the mole% ratio exceeds this range, the balance as a heat-resistant polyimide film such as flexibility, rigidity, strength, elastic modulus water absorption, hygroscopic expansion coefficient, and elongation is lost.

Although what can be used other than said aromatic diamines and aromatic tetracarboxylic acids is not specifically limited, For example, it shows as follows.
5-amino-2- (p-aminophenyl) benzoxazole, 6-amino-2- (p-aminophenyl) benzoxazole, 5-amino-2- (m-aminophenyl) benzoxazole, 6-amino-2 -(M-aminophenyl) benzoxazole, 4,4'-bis (3-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl] Sulfide, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 3,3′-diaminodiphenyl sulfide, 3,3′-diaminodiph Nyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4'-diaminodiphenyl sulfoxide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3, 3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, bis [4- (4-aminophenoxy) phenyl] methane, 1,1-bis [4- (4-aminophenoxy) phenyl] ethane, 1,2-bis [4- (4-aminophenoxy) phenyl] ethane, 1,1- Bis [4- (4-aminophenoxy) phenyl] propane, 1,2-bis [4- ( 4-aminophenoxy) phenyl] propane, 1,3-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane.
Some or all of the hydrogen atoms on the aromatic ring in the aromatic diamine are halogen atoms, alkyl groups having 1 to 3 carbon atoms or alkoxyl groups, cyano groups, or some or all of hydrogen atoms of alkyl groups or alkoxyl groups. An aromatic diamine substituted with a halogenated alkyl group having 1 to 3 carbon atoms substituted with a halogen atom or an alkoxyl group is exemplified.

  Bisphenol A bis (trimellitic acid monoester acid anhydride), 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propanoic acid anhydride, 3,3 ′, 4,4′-benzophenone tetra Carboxylic dianhydride, 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene Tetracarboxylic dianhydride, 4,4′-oxydiphthalic anhydride, 3,3 ′, 4,4′-dimethyldiphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic acid Anhydrides, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylpropanoic acid dianhydride, 4,4′-hexafluoroisopropylidenediphthalic anhydride and the like.

In the present invention, a green film is formed from an aromatic polyamic acid solution and then subjected to high-temperature heat treatment or dehydration condensation (imidization).
As preferred production example, a polyimide precursor film (green film) on one side (A side) of the imidization ratio IM _A and another one side imidization rate IM _B and the formula of the relationship (B side) The polyimide precursor film (green film) which satisfy | fills is manufactured, and then the polyimide precursor film (green film) is imidized.
Formula 1; | IM _A −IM _B | ≦ 5

In the present invention, the imidation ratio of the green film is measured as follows.
<Measurement method of imidization ratio>
The film to be measured is sampled to a size of 2 cm × 2 cm, the measurement object surface is brought into close contact with the ATR crystal, set in an IR measurement apparatus, and the following specific wavelength absorbance is measured. Get a conversion rate.
Adopting ₁₇₇₈ cm ⁻¹ (near) as the specific wavelength of imide and the absorbance of the measurement surface at that wavelength as λ ₁₇₇₈ , adopting the vicinity of specific wavelength 1478 cm ⁻¹ of the aromatic ring as the reference and the absorbance of the measurement surface at that wavelength as λ ₁₄₇₈ To do.
Equipment: FT-IR FTS60A / 896 (Digilab Japan Co., Ltd.)
Measurement conditions: 1-time reflection ATR attachment (SILVER GATE)
ATR crystal Ge
Incident angle 45 °
Detector DTGS
Resolution 4cm ^-1
Accumulation count 128 times Formula 2; IM = {Iλ / I (450)} × 100
In Formula 2, Iλ = (λ ₁₇₇₈ / λ ₁₄₇₈ ), and I (450) was measured in the same manner as a film obtained by thermal ring-closing imidization of a polyimide precursor film having the same composition at 450 ° C. for 15 minutes (λ ₁₇₇₈ / λ ₁₄₇₈ ).
The imidization rate IM of surface B imidation rate IM of surface A as IM _A may measure these values from equation 2 as IM _B. The difference between IM _A and IM _B is shown with an absolute value.
The measured value is 2 points (1/3 and 2/3 points of the width length) in the width direction at any part of the film, and the measured value is the average value of the 2 points.

The method for producing the specific green film is not particularly limited, and preferred examples include the following methods.
When the green film is dried to such an extent that self-supporting properties are obtained, the direction of volatilization of the solvent is limited to the surface in contact with air, so the imidization ratio of the surface in contact with air of the green film is in contact with the support. Although it tends to be smaller than the imidation rate of the surface, in order to obtain a polyimide long film having a difference in absorption ratio of the film front and back of 0.35 or less, the imidization rate on the front and back surfaces and the difference are within a predetermined range. It is important to obtain a certain green film. For this purpose, for example, there is a method of controlling the drying conditions when a polyamic acid solution is coated on a support and dried to obtain a self-supporting green film. By this control, it is possible to obtain a green film in which the imidization ratio of the front and back surfaces of the green film and the difference are within a predetermined range.
The difference in the imidization rate between the front and back surfaces of these green films is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less. It is better to control to the range.
When the difference in the imidization ratio between the front and back surfaces of the green film exceeds 5, potentially existing strain inside the film remains, curls occur after heat treatment at 300 ° C., and is not suitable for commercialization. It becomes.

In addition, when the green film is dried to such an extent that self-supporting properties are obtained, a green film having a predetermined range of imidization ratios on the front and back surfaces and the difference between them is controlled by controlling the amount of residual solvent with respect to the total mass after drying. Can do. Specifically, it is important that the amount of residual solvent with respect to the total mass after drying is preferably 25 to 50% by mass, more preferably 35 to 50% by mass. When the residual solvent amount is lower than 25% by mass, the imidization rate on one side of the green film becomes relatively high, and it becomes difficult to obtain a green film with a small difference in imidization rate between the front and back surfaces. In addition, the green film tends to become brittle due to a decrease in molecular weight. Moreover, when it exceeds 50 mass%, self-supporting property becomes inadequate and conveyance of a film becomes difficult in many cases.
In order to achieve such conditions, a drying apparatus such as hot air, hot nitrogen, far infrared rays, and high frequency induction heating can be used, but the following temperature control is required as the drying conditions.
When performing hot air drying, when drying the green film to the extent that self-supporting properties are obtained, the constant rate drying conditions should be lengthened in order to keep the imidization rate range and the difference between the green film front and back surfaces within a predetermined range. It is preferable to operate so that the solvent is uniformly volatilized from the entire coating film. Constant rate drying is a drying region in which the coating film surface is a free liquid surface and the volatilization of the solvent is governed by mass transfer in the outside world. Under the drying conditions where the coating surface is dried and solidified and the solvent diffusion within the coating is rate-limiting, the physical property difference between the front and back surfaces is likely to occur. The preferable dry state varies depending on the type and thickness of the support, but the temperature setting, the air flow setting, and the atmospheric temperature above the coating film (green film) on the support (green film side) are usually higher than those described above. The coating film is dried under conditions where the ambient temperature on the opposite side (opposite side of the coating film side) is 1 to 55 ° C. higher. In the description of the atmospheric temperature, the direction is defined with the direction from the coating film toward the support being the downward direction and the opposite being the upward direction. Such a description in the vertical direction is made for concisely expressing the position of the region to be noted, and is not for specifying the absolute direction of the coating film in actual production.

The “atmosphere temperature on the coating film side” is a temperature in a region (usually a space) from directly above the coating film to 30 mm on the coating film side, and a temperature at a position 5 to 30 mm away from the coating film in the upward direction. By measuring with a thermocouple or the like, the ambient temperature on the coating film surface side can be determined.
The “atmospheric temperature on the opposite side” is the temperature in the region (often including the support and the lower part of the support) from directly below the coating (support part) to the lower 30 mm of the coating. By measuring the temperature at a position 5 to 30 mm downward from the membrane with a thermocouple or the like, the atmosphere temperature on the opposite side can be obtained.

  When drying, if the atmospheric temperature on the opposite side is higher by 1 to 55 ° C. than the atmospheric temperature on the coating film side, a high-quality film can be obtained even if the drying temperature is increased and the drying speed of the coating film is increased. be able to. If the atmospheric temperature on the opposite surface side is lower than the atmospheric temperature on the coating surface side, or if the difference between the atmospheric temperature on the coating surface side and the atmospheric temperature on the opposite side is less than 1 ° C., the vicinity of the coating surface is first There is a concern that the film may be dried into a film to form a “lid”, and thereafter, the evaporation of the solvent to be evaporated from the vicinity of the support is hindered, and the internal structure of the film is distorted. It is undesirable for the apparatus and the economy to be disadvantageous in that the atmospheric temperature on the opposite side is higher than the atmospheric temperature on the coating film side and the temperature difference is greater than 55 ° C. Preferably, at the time of drying, the ambient temperature on the opposite side is higher by 10 to 50 ° C., more preferably 15 to 45 ° C. than the ambient temperature on the coating film side.

The setting of the atmospheric temperature as described above may be performed over the entire process of drying the coating film, or may be performed in a part of the process of drying the coating film. When the coating film is dried by a continuous dryer such as a tunnel furnace, the above-mentioned atmospheric temperature may be set in the drying effective length, preferably 10 to 100%, more preferably 15 to 100%. .
The drying time is 10 to 90 minutes in total, desirably 15 to 45 minutes.

The green film that has undergone the drying step is then subjected to an imidization step, but may be either inline or off-line.
When the off-line is adopted, the green film is wound up once. At this time, curling can be reduced by winding the green film on the tubular body so that the green film is on the inner side (the support is on the outer side).
In any case, it is preferable to carry or wind the film so that the radius of curvature does not become 30 mm or less.

The degree of curl after the 300 ° C. heat treatment of the present invention is low by imidizing a green film obtained by such a method with the imidation ratio of the front and back surfaces and the difference thereof controlled within a predetermined range under predetermined conditions. A polyimide long film is obtained.
As a specific imidization method, a conventionally known imidation reaction can be appropriately used. For example, using a polyamic acid solution that does not contain a ring-closing catalyst or a dehydrating agent, the imidization reaction proceeds by subjecting it to a heat treatment (so-called thermal ring-closing method), or the polyamic acid solution contains a ring-closing catalyst and a dehydrating agent. In particular, a chemical ring closing method in which an imidization reaction is performed by the action of the above ring closing catalyst and a dehydrating agent can be used. A polyimide long film having a curl degree of 10% or less after 300 ° C. heat treatment of a polyimide long film is included. In order to obtain a film, the thermal ring closure method is preferred.

100-500 degreeC is illustrated as a heating maximum temperature of a thermal ring closure method, Preferably it is 200-480 degreeC. When the maximum heating temperature is lower than this range, it is difficult to close the ring sufficiently, and when it is higher than this range, deterioration proceeds and the film tends to become brittle. A more preferable embodiment includes a two-stage heat treatment in which treatment is performed at 150 to 250 ° C. for 3 to 20 minutes and then treatment is performed at 350 to 500 ° C. for 3 to 20 minutes.
In the chemical ring closure method, after the polyamic acid solution is applied to a support, the imidization reaction is partially advanced to form a self-supporting film, and then imidization can be performed completely by heating. In this case, the condition for partially proceeding with the imidization reaction is preferably a heat treatment for 3 to 20 minutes at 100 to 200 ° C., and the condition for allowing the imidization reaction to be completely performed is preferably 200 to 400 ° C. For 3 to 20 minutes.

The above-mentioned drying treatment and imidization treatment are carried out by gripping both ends of the film with a pin tenter or clip. At that time, in order to maintain the uniformity of the film, it is desirable to make the tension in the width direction and the longitudinal direction of the film as uniform as possible.
Specifically, just before the film is subjected to a pin tenter, the both ends of the film can be pressed with a brush, and the pins can be pierced uniformly into the film. The brush is preferably a fibrous material having rigidity and heat resistance, and a high-strength, high-modulus monofilament can be adopted.
By satisfying the conditions (temperature, time, tension) of the imidization treatment described above, it is possible to suppress the occurrence of orientation strain inside the film (front and back and plane direction).

The timing for adding the ring-closing catalyst to the polyamic acid solution is not particularly limited, and may be added in advance before the polymerization reaction for obtaining the polyamic acid. Specific examples of the ring-closing catalyst include aliphatic tertiary amines such as trimethylamine and triethylamine, and heterocyclic tertiary amines such as isoquinoline, pyridine, and betapicoline. Among them, heterocyclic tertiary amines are mentioned. At least one amine selected from is preferred. Although the usage-amount of a ring-closing catalyst with respect to 1 mol of polyamic acids does not have limitation in particular, Preferably it is 0.5-8 mol.
The timing of adding the dehydrating agent to the polyamic acid solution is not particularly limited, and may be added in advance before the polymerization reaction for obtaining the polyamic acid. Specific examples of the dehydrating agent include aliphatic carboxylic acid anhydrides such as acetic anhydride, propionic anhydride, butyric anhydride, and aromatic carboxylic acid anhydrides such as benzoic anhydride. Among them, acetic anhydride, benzoic anhydride, etc. Acids or mixtures thereof are preferred. Moreover, the usage-amount of the dehydrating agent with respect to 1 mol of polyamic acids is not particularly limited, but is preferably 0.1 to 4 mol. When a dehydrating agent is used, a gelation retarder such as acetylacetone may be used in combination.

Whether it is a thermal cyclization reaction or a chemical cyclization method, the polyimide long film precursor (green sheet, film) formed on the support may be peeled off from the support before it is completely imidized. It may be peeled off after imidation.
Although the thickness of a polyimide long film is not specifically limited, When considering using it for the base substrate for printed wiring boards mentioned later, it is 1-150 micrometers normally, Preferably it is 3-50 micrometers. This thickness can be easily controlled by the amount of the polyamic acid solution applied to the support and the concentration of the polyamic acid solution.
The polyimide long film obtained by the production method of the present invention is preferably a polyimide long film having a smaller curl degree by winding the A side in the winding with the absorption ratio tending to be larger than the B side into a tubular product. Can be obtained. When winding on a tubular object with the A-side in the winding, the radius of curvature is preferably in the range of 30 mm to 600 mm. If the radius of curvature exceeds this range, the curl degree of the polyimide long film may increase.
Further, the winding tension is 100N or more, preferably 150N or more and 500N or less.
Therefore, when roll-rolling a polyimide long film, as a preferred embodiment for improving curl, the A side is in the winding, the radius of curvature is relatively large, 30 to 600 mm, preferably 80 to 300 mm, and the winding tension. Can be adopted.
Moreover, in order to reduce the physical property difference between the winding core side (roll inner layer side) and the winding outer side (roll outer layer side) of the wound film as much as possible, the winding tension increases as the curvature radius of the film increases ( It is desirable to decrease the winding tension on the winding core side and increase the winding tension on the winding outer side.
Further, when the green film is imidized offline, a method of winding the green film so that the green film is on the inside (the support is on the outside) can be employed.

In addition, the above-mentioned absorption ratio means the degree of orientation with respect to the film surface of the imide ring surface of the polyimide molecule from the film surface (or back surface, hereinafter the same) to a depth of about 3 μm. Specifically, polarization ATR measurement is performed by FT-IR (measurement apparatus: Digilab, FTS-60A / 896, etc.), single reflection ATR attachment is golden gate MkII (SPECAC), IRE is diamond, incident angle the 45 °, the resolution 4 cm ^-1, the absorption coefficient in each direction at the peak appearing near 1480 cm ^-1 in the case of the film surface was measured at 128 cumulative conditions (aromatic ring vibration) (Kx, Ky and Kz ) And is defined by the following equation. (However, Kx is the MD direction, Ky is the TD direction, and Kz is the thickness direction absorption coefficient.)
Absorption ratio = (Kx + Ky) / 2 × Kz
The measured value is 2 points (1/3 and 2/3 points of the width length) in the width direction at any part of the film, and the measured value is the average value of the 2 points.
In the present invention, the A surface is the surface having the larger absorption ratio, and the B surface is the surface having the smaller absorption ratio.

The polyimide long film is heat treated in the green film drying process or imidization process. At that time, if there are uneven spots in the width direction of the film, a difference in physical properties in the width direction of the film occurs, which causes curling.
Therefore, in the present invention, it is desirable to control the unevenness in the width direction of the ambient temperature in the dryer within a central temperature of ± 5 ° C., preferably within ± 3 ° C., and more preferably within ± 2 ° C.
Here, the atmospheric temperature refers to a temperature measured with a thermocouple, a thermo label, or the like at a position away from the surface of the support by an equal distance of 5 mm to 30 mm. In the present invention, it is preferable to provide 8 to 64 temperature detection ends in the width direction.
In particular, the interval between the detection end in the width direction is preferably about 5 cm to 10 cm. As the detection end, a known thermocouple such as alumel chromel may be used.
In the present invention, the ambient temperature on the opposite side can be set higher by 5 to 55 ° C. than the ambient temperature on the coated surface side. In this case as well, it is important that the temperature is within a range of ± 5 ° C. from the center temperature of the temperature on each side of the support. The center temperature is the arithmetic average value of the Celsius temperature measured at each detection end, and the temperature measured at each detection end in the width direction perpendicular to the direction in which the support travels is within ± 5 ° C. Is a range calculated based on the numerical value of the central value.
The polyimide long film manufactured under such conditions has excellent flatness at an extremely high temperature with a curl degree measured under the above conditions of 10% or less.

Although the thickness of the polyimide film as a base material of the present invention is not particularly limited, it is usually 1 to 150 μm, preferably 3 to 50 μm in consideration of use for a base material of an electronic substrate. This thickness can be easily controlled by the amount of the polyamic acid solution applied to the support and the concentration of the polyamic acid solution.
In the polyimide film as the substrate of the present invention, it is preferable to impart a fine unevenness to the film surface by adding a lubricant to the polyimide, thereby improving the slipping property of the film.
As the lubricant, inorganic or organic fine particles having an average particle diameter of about 0.03 to 3 μm can be used. Specific examples include titanium oxide, alumina, silica, calcium carbonate, calcium phosphate, calcium hydrogen phosphate, calcium pyrophosphate, Examples include magnesium oxide, calcium oxide, and clay minerals.
The polyimide film of the present invention is usually an unstretched film, but may be stretched uniaxially or biaxially. Here, the unstretched film refers to a film obtained without intentionally applying a mechanical external force in the surface expansion direction of the film by tenter stretching, roll stretching, inflation stretching, or the like.

As described above, it is desirable that the roll on which the polyimide film according to the present invention is wound has a winding tension of 100 N or more and a curvature radius of 30 to 600 mm. The polyimide film obtained by the above method is less warped or distorted and has excellent flatness, but in the present invention, these characteristics are homogeneous with respect to the longitudinal direction of the film. . That is, it is desirable that the variation rate (standard deviation × 100 / average value) (CV%) of the linear expansion coefficient of the film on the winding side and the core side is 25% or less. Preferably, it is 20% or less, more preferably 15% or less.
Here, the method of measuring the linear expansion coefficient is as follows.
For the polyimide film to be measured, the stretch rate in the MD direction and the TD direction is measured under the following conditions, and the stretch rate / temperature at intervals of 30 ° C. to 45 ° C., 45 ° C. to 60 ° C.,. This measurement was performed up to 300 ° C., and the average value of all measured values was calculated as the coefficient of linear expansion (CTE).
Device name: TMA4000S manufactured by MAC Science
Sample length; 20mm
Sample width: 2 mm
Temperature rise start temperature: 25 ° C
Temperature rising end temperature: 400 ° C
Temperature increase rate: 5 ° C / min
Atmosphere; Argon Sampling of sample pieces was measured at a pitch of 1/5 of the total length in the longitudinal direction with 2 points (1/3 and 2/3 of the width) in the width direction of the polyimide film roll. 10 points.
Then, the fluctuation rate for 10 points is calculated.

Usually, when a film is rolled, a so-called winding occurs in which the film warps in the winding direction at the time of unwinding, and the warpage is different between the film on the winding core side and the film on the winding side. Furthermore, the roll of the polyimide film according to the present invention has a very small difference in physical properties between the winding core side and the winding outer side, and the difference in the degree of warpage of the film in each part is 5% or less, preferably 3% or less. It will be excellent.
In the present invention, the degree of warping of the film (apparent warping degree) is specifically, as shown in FIG. 1, a test piece of 50 mm × 50 mm is taken from a polyimide film test piece released from a roll on a plane. The average value of the distances from the four corner planes (h1, h2, h3, h4: unit mm) is the amount of warpage (mm), and the distance from each vertex of the test piece to the center ( 35.36 mm) is a value expressed as a percentage (%) of the warpage amount.
Specifically, it is calculated by the following formula.
Warpage (mm) = (h1 + h2 + h3 + h4) / 4
Degree of warpage (%) = 100 × (curl amount) /35.36
Sampling of the sample piece was performed at 2 points (1/3 and 2/3 of the width) in the width direction of the polyimide film roll, and a total of 10 points at a length pitch of 1/5 of the entire length in the longitudinal direction. To do.

Next, the metallized polyimide film of the present invention will be described.
The metallization treatment described below may be performed batchwise with a piece of film obtained by cutting the above polyimide film roll, or may be wound up as a metallized polyimide film roll by continuously treating the polyimide film roll. (Roll toe roll).
In the metallized polyimide film of the present invention, the polyimide basically has at least a pyromellitic acid residue as an aromatic tetracarboxylic acid residue and a diaminodiphenyl ether residue as an aromatic diamine residue, and Using a polyimide film (IF) with a curl degree of 10% or less after heat treatment at 300 ° C. as a base material, a base metal layer (UM) that is formed by a dry plating method and a metal thin film layer that is always formed A conductive thin film layer (dM), and a thick metal layer (DM) appropriately formed on the conductive thin film layer.

  When forming a conductive metal layer (conductive thin film layer) on the surface of a polyimide film as a base material, it is preferable to first form a layer by sputtering of a nickel-chromium alloy as the base layer, and the thickness of the base layer Is 20-2000 cm, preferably 40-1000 cm, and more preferably 80-500 cm. If the layer thickness by sputtering of the nickel-chromium alloy is less than 20 mm, the adhesion to the base film is not sufficient, and if it exceeds 2000 mm, abnormal deposition of metal in the electroless plating or the like to be performed after that significantly occurs. It will be. The chromium content in the nickel-chromium alloy is desirably 1 to 10% by mass, more preferably 2 to 8%, and still more preferably 3 to 6%. If the chromium content is less than 1% by mass, the effect of improving the migration resistance is not present, and if it exceeds 10% by mass, the effect of improving the migration resistance is almost the same. There is a problem that, for example, copper residue remains at the time of pattern formation. For example, the copper layer, which is a conductive layer provided on the nickel-chromium alloy sputtered layer, preferably has a thickness of 1 to 12 μm, more preferably 1 to 9 μm, and even more preferably about 2 to 5 μm. Is appropriate.

  In the present invention, the polyimide has at least a pyromellitic acid residue as an aromatic tetracarboxylic acid residue, a diaminodiphenyl ether residue as an aromatic diamine residue, and the degree of curl after 300 ° C. heat treatment of the film. After the surface of the polyimide film of 10% or less is subjected to plasma treatment, a nickel-chromium alloy as an underlayer is deposited by sputtering so as to have a thickness of 20 to 2000 mm, and then a metal thin film layer such as copper is sputtered and It is preferable to deposit by a dry plating method such as vapor deposition or the like, and then perform thickening metal by electrolytic plating or the like to form a thick film metal layer, and further perform annealing treatment or heat treatment at 200 to 350 ° C.

  The surface of the polyimide film is preferably subjected to surface treatment by plasma treatment, and the plasma is an inert gas plasma, and nitrogen gas, Ne, Ar, Kr, and Xe are used as the inert gas. There is no particular limitation on the method for generating plasma, and an inert gas may be introduced into the plasma generator to generate plasma. There is no particular limitation on the plasma treatment method, and a plasma treatment apparatus used for forming a base metal layer or a metal thin film layer on a base film may be used. The time required for the plasma treatment is not particularly limited, and is usually 1 second to 30 minutes, preferably 10 seconds to 10 minutes. There are no particular restrictions on the frequency and output of the plasma during the plasma processing, the gas pressure for generating the plasma, and the processing temperature as long as they can be handled by the plasma processing apparatus. The frequency is usually 13.56 MHz, the output is usually 50 W to 1000 W, the gas pressure is usually 0.01 Pa to 10 Pa, and the temperature is usually 20 ° C. to 250 ° C., preferably 20 ° C. to 180 ° C. If the output is too high, the substrate film surface may crack. Moreover, when gas pressure is too high, there exists a possibility that the smoothness of the surface of a base film (electrical insulating layer) may fall.

Next, a nickel-chromium alloy as an underlayer is deposited on the surface-treated surface by sputtering to form a nickel-chromium alloy sputter layer having a thickness of 20 to 2000 mm. The sputtering conditions are arbitrary. The sputter layer of nickel-chromium alloy may be a method using a nickel-chromium alloy target, a method of performing dual simultaneous sputtering, or a method of sputtering nickel and chromium independently and diffusing both in a later step. Can do.
Next, a metal thin film layer is formed. The metal thin film layer is a conductive layer, and the conductive layer is formed by a so-called dry plating method such as a sputtering method, a vapor deposition method, an ion plating method, or a CVD method, but a sputtering method or a vapor deposition method is preferable. As the vapor deposition method, electron beam vapor deposition is preferable in that the contamination of the crucible material is small.

  There is no particular limitation on the sputtering method as a preferable method in the formation of the underlayer or the metal thin film layer (metal layer). Plasma controlled sputtering, multi-target sputtering, or the like can be used. Among these, direct current bipolar sputtering or high frequency sputtering is preferable. There are no particular restrictions on the output during sputtering processing, the gas pressure for generating plasma, and the processing temperature, so long as they can be handled by the sputtering apparatus. The output is usually 10 W to 1000 W, the gas pressure is usually 0.01 Pa to 10 Pa, and the temperature is usually 20 ° C. to 250 ° C., preferably 20 ° C. to 180 ° C. The film forming rate is 0.1 Å / second to 1000 Å / second, preferably 1 Å / second to 100 Å / second. If the film formation rate is too high, the formed metal thin film layer may be cracked. Moreover, when gas pressure is too high, there exists a possibility that adhesiveness may fall.

In the present invention, after a nickel-chromium alloy sputter layer as an underlayer, a metal thin film layer of about 0.1 to 3 μm, for example, a copper layer is first formed as a conductive layer by any one of dry plating methods such as sputtering and vapor deposition. After that, a method of further increasing the thickness of the copper layer by wet plating such as electroplating as the thick metal layer (thick film layer) can be preferably used.
The metal as the metal thin film layer or thick metal layer of the present invention is silver, copper, gold, platinum, rhodium, nickel, aluminum, iron, chromium, zinc, tin, brass, white copper, bronze, monel, tin-lead solder , Tin-copper-based solder, tin-silver-based solder or the like alone or an alloy thereof is used, but copper is a preferred embodiment in terms of the balance between performance and economy.

In the above dry plating example, the film being deposited is maintained at 100 to 400 ° C., preferably 150 to 350 ° C., so that the adhesion between the base metal layer and the metal thin film layer (for example, the copper thin film layer) is It will be more robust. In such a process, it is presumed that a part of the base alloy and the deposited metal diffuse to each other, and a region having a composition gradient is formed at the interface.
The copper thick film layer preferably used as the metal thick film layer of the present invention can be formed by electroplating or electroless plating. As the electroplating method, copper pyrophosphate plating or copper sulfate plating can be preferably used.
In particular, when a copper foil thickness of less than about 4 μm is required, a predetermined thickness can be formed by a vacuum deposition method or the like, and a metallized film can be obtained without electroplating. In such a case, it is possible to obtain a metallized film in which an inorganic substance that may contaminate the film accompanying electroplating, that is, salts and sulfate radicals are not mixed.

  In this invention, it is a preferable aspect to heat-process the metallized film which is a composite_body | complex of the polyimide film and metal obtained by the said method at 200-350 degreeC further. This heat treatment is preferably 220 to 330 ° C, more preferably 240 to 310 ° C. The heat treatment reduces the strain of the base film and the strain generated in the manufacturing process of the metalized polyimide film, and can more effectively express the effects of the present invention. And reliability can be improved. If it is less than 200 ° C., the effect of alleviating the strain becomes small. Conversely, if it exceeds 350 ° C., the polyimide film of the base material is deteriorated, which is not preferable.

The metallized polyimide film of the present invention thus obtained is coated with a photoresist on the conductive metal thin film layer and / or thick metal layer side and dried, followed by exposure, development, etching, photo Form the circuit pattern by the resist stripping process, and apply the solder resist, harden and electroless tin plating as necessary, then directly print the flexible printed circuit board, the multilayer printed circuit board that multiplies them, and the semiconductor chip directly. A printed wiring board mounted thereon is obtained.
On the surface of the metal thin film layer and / or thick metal layer (copper layer) used in the present invention, an inorganic coating such as a single metal or a metal oxide may be formed. Further, the surface of the metal thin film layer and / or the thick metal layer may be subjected to a treatment with a coupling agent (aminosilane, epoxysilane, etc.), a sand plast treatment, a hole treatment, a corona treatment, a plasma treatment, an etching treatment or the like. .

EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated more concretely, this invention is not limited by a following example. In addition, the evaluation method of the physical property in a following example is as follows, and the curl degree after 300 degreeC heat processing is as above-mentioned method.
1. The thickness of the polyimide film The thickness was measured using a micrometer (Millitron 1254D manufactured by Fine Reef).
2. Degree of warpage of conductive film (apparent degree of warpage)
As shown in FIG. 1 (C), a film test piece of 50 mm × 50 mm was left to be concave on the plane, and the average of distances from the four corner planes (h1, h2, h3, h4: unit mm) The value is a value expressed as a percentage (%) of the warpage amount with respect to the distance (35.36 mm) from each vertex to the center of the test piece, where the value is the warpage amount (mm).
Specifically, it is calculated by the following formula.
Warpage (mm) = (h1 + h2 + h3 + h4) / 4
Degree of warpage (%) = 100 × (warpage amount) /35.36
Sampling of the sample piece is performed at two points in both the width direction and the length direction of the conductive polyimide film (in principle, from the points 1/3 and 2/3 of the width length, if not possible, the point is taken from the center as much as possible. ) A total of 4 points shall be represented by the average value.

Abbreviations of compounds used in Examples and the like are described below.
PMDA: pyromellitic dianhydride TMHQ: P-phenylenebis (trimellitic acid monoester anhydride)
ODA: 4,4′-diaminodiphenyl ether P-PDA: paraphenylenediamine BPDA: 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride DMF: dimethylformamide DMAC: dimethylacetamide AA: acetic anhydride IQ: isoquinoline Abbreviation GF indicates a polyimide precursor film (green film), and abbreviation IF indicates a polyimide film.

(Production Example A; Real-1 to Real-3)
A container equipped with a nitrogen introduction tube, a thermometer, and a stirring rod was purged with nitrogen, and then ODA was added. Next, after adding DMAC and completely dissolving it, PMDA is added, and ODA and PMDA as monomers are polymerized in DMAC at a molar ratio of 1/1 so that the monomer charge concentration becomes 15% by mass. When stirred at 25 ° C. for 5 hours, a brown viscous polyamic acid solution was obtained.
15 parts by mass of AA and 3 parts by mass of IQ are mixed with 100 parts by mass of the obtained polyamic acid solution, and this is mixed with a polyester film (Cosmo Shine A4100, manufactured by Toyobo Co., Ltd.) having a thickness of 188 μm and a width of 800 mm. ) Was coated to a width of 740 mm (squeegee / belt gap was 430 μm) and passed through a continuous drying oven having four drying zones. Each zone has three rows of slit-shaped air outlets above and below the film. The hot air temperature between the air outlets can be controlled within a range of plus or minus 1.5 ° C and the air volume difference can be controlled within a range of plus or minus 3%. Has been. The width direction is controlled to be within ± 1 ° C. until a width corresponding to 1.2 times the effective film width.

The setting of the drying oven is as follows.
Leveling zone temperature 25 ° C, no air volume 1st zone upper temperature 105 ° C, lower temperature 105 ° C
Air volume 20-25 cubic m / min for both top and bottom Zone 2 Upper temperature 100 ° C, Lower temperature 100 ° C
Air volume 30 to 35 cubic m / min in both upper and lower zones Third zone Upper temperature 95 ° C, Lower temperature 100 ° C
Air volume 20-25 cubic m / min on both top and bottom Zone 4 Upper temperature 90 ° C, Lower temperature 100 ° C
Upper airflow 15-18 cubic m / min, lower airflow 20-25 cubic m / min The length of each zone is the same, and the total drying time is 18 minutes.
Further, the air volume is the total of the air volumes from the outlets of each zone, and is changed within the above range for Real-1, Real-2, and Real-3.

Under such drying conditions, it has been confirmed that the surface of the coating film does not reach a dry-to-touch state until the third zone, and is almost constant rate drying conditions.
The surface of the coating film was dry to the touch shortly after entering the fourth zone, and thereafter, the drying progressed in a decelerating manner. At this time, the lower temperature and the air volume are set higher than the upper side to promote the diffusion of the solvent in the coating film.
In addition, it is confirmed that the temperature is within ± 1.5 ° C. by monitoring at intervals of 10 cm by a thermocouple supported at a position of 10 mm on the film at the portion directly below the blowout port at the center of each zone.

The polyamic acid film that became self-supporting after drying was peeled from the polyester film to obtain green films, GF Real-1, GF Real-2, and GF Real-3.
Each green film obtained was passed through a continuous heat treatment furnace purged with nitrogen while holding both ends with a pin tenter, and the first stage was heated at 180 ° C. for 5 minutes and at a heating rate of 4 ° C./second. Then, as the second stage, two-stage heating was performed at 400 ° C. for 5 minutes to advance the imidization reaction. Then, each polyimide film which exhibits brown, IF real-1, IF real-2, IF real-3 was obtained by cooling to room temperature in 5 minutes.
In addition, when heat-treating the green film, a brush made of an aromatic polyamide monofilament strand was provided so as to be in contact with both ends of the film so that both ends of the film pierced uniformly into the pins of the pin tenter.
The thickness and curl degree of each polyimide film obtained were 25 μm and 2.8% for IF real-1, 25.1 μm and 4.1% for IF real-2, and 25 μm and 7.5 for IF real-3. %Met.
The obtained polyimide film was rolled up into a roll under the following conditions to obtain a film roll.
Winding method: Inner winding Winding tension: 145 to 155N
Roll curvature radius: 84mm
Among them, the film properties of the roll film of IF Real-1 were as follows.
Fluctuation rate of linear expansion coefficient: 11%
Maximum warpage: 2.2%
Minimum warpage: 0.7%

(Production Example B; Real-4 to Real-6)
PMDA and BPDA are used as aromatic tetracarboxylic dianhydride components, and four types of monomers, ODA and P-PDA, are used as diamine components, and PMDA / BPDA / ODA / P-PDA is 1 / 0.5 / 1/0. Polymerization was carried out in DMF at a molar ratio of 0.5 to prepare a DMF solution of polyamic acid so that the monomer charge concentration was 16% by mass. The obtained polyamic acid solution was coated on a stainless steel belt (the gap between the squeegee / belt was 400 μm) and dried in the same manner as in Production Example A ; The polyamic acid film which became self-supporting after drying was peeled from the stainless steel belt to obtain 49.5 μm-thick green films, GF Real-4 to GF Real-6.
The obtained green film was passed through a continuous heat treatment furnace purged with nitrogen, the first stage was heated at 180 ° C. for 3 minutes, and the heating rate was 4 ° C./second, and the second stage was at 460 ° C. for 2 minutes. The imidation reaction was allowed to proceed by applying two stages of heating under the conditions described above. Then, it cooled to room temperature in 5 minutes, and obtained each 25-micrometer-thick polyimide film, IF real-4, IF real-5, and IF real-6 which exhibited brown.
In addition, when heat-treating the green film, a brush made of an aromatic polyamide monofilament strand was provided so as to be in contact with both ends of the film so that both ends of the film pierced uniformly into the pins of the pin tenter.
The thickness and curl degree of each polyimide film obtained were 25 μm and 4.8% for IF -4, 25.1 μm and 7.8% for IF -5, 25 μm and 9.5 for IF -6. %Met.
The obtained polyimide film was rolled up into a roll under the following conditions to obtain a film roll.
Winding method: Inner winding Winding tension: 140-162N
Roll curvature radius: 84mm
Among them, the film characteristics of the roll film of IF Real-4 were as follows.
Variation rate of linear expansion coefficient: 10%
Maximum degree of warpage: 0.6%
Minimum warpage: 0.1%

(Production Example C; ratio-1 to ratio-3)
15 parts by mass of AA and 3 parts by mass of IQ are mixed with 100 parts by mass of the polyamic acid solution obtained in Production Example A , and this is coated on a stainless steel belt (the gap between the squeegee / belt is 430 μm), Production Example A : Drying was performed using the same drying apparatus as in Examples -1 to -3, and the drying conditions (temperature is the set temperature of the drying furnace) are as follows.
Leveling zone 25 ° C, no air flow 1st zone temperature 110 ° C
Air volume 20-25 cubic m / min on both top and bottom Zone 2 Temperature 120 ° C on both top and bottom
Air volume 20-25 cubic m / min for both top and bottom Zone 3 Temperature 120 ° C for both top and bottom
Air volume 20-25 cubic m / min on both top and bottom Zone 4 Temperature 120 ° C on both top and bottom
Airflow 20-25 cubic m / min in both the top and bottom The length of each zone is the same, and the total drying time is 9 minutes.
The air volume is the total of the air volumes from the outlets of each zone, and is changed within the above range by ratio-1, ratio-2, and ratio-3.
Under such drying conditions, it can be inferred that the surface of the coating film is dry to the touch at the center of the second zone, and thereafter drying at a reduced rate is performed.

The polyamic acid film that became self-supporting after drying was peeled from the stainless steel belt to obtain three types of green films, GF ratio-1, GF ratio-2, and GF ratio-3.
Each green film obtained was passed through a continuous heat treatment furnace purged with nitrogen while holding both ends with a pin tenter, and the first stage was heated at 180 ° C. for 5 minutes and at a heating rate of 4 ° C./second. Then, as the second stage, two-stage heating was performed at 400 ° C. for 5 minutes to advance the imidization reaction. Then, each polyimide film which exhibits brown, IF ratio-1, IF ratio-2, and IF ratio-3 was obtained by cooling to room temperature in 5 minutes.
The thickness and curl degree of each polyimide film obtained were 25 μm and 10.8% at an IF ratio of −1, 25.1 μm and 14.1% at an IF ratio of −2, and 25 μm and 22.5 at an IF ratio of −3. %Met.

(Examples 1-6, Comparative Examples 1-3)
Each film obtained in the production example was cut into a square of 25 cm × 25 cm, and 5 films were used each.
Each film was fixed by being sandwiched between stainless steel frames having openings with a diameter of 24 cm. Next, plasma treatment of the film surface was performed. The plasma treatment conditions were a xenon gas, a frequency of 13.56 MHz, an output of 100 W, a gas pressure of 0.8 Pa, a treatment temperature of 25 ° C., and a treatment time of 5 minutes. Next, using a nickel-chromium (3%) alloy target under conditions of a frequency of 13.56 MHz, an output of 400 W, a gas pressure of 0.8 Pa, and a thickness of 50 mm at a rate of 10 mm / second by RF sputtering in a xenon atmosphere. A nickel-chromium alloy underlayer was formed. Next, the temperature of the substrate was raised to 250 ° C., and copper was vapor-deposited at a rate of 100 Å / sec to form a copper thin film layer having a thickness of 0.5 μm to obtain each metal thin film layer-formed metallized film.
Each metal thin film layer-forming gold film obtained was fixed to a plastic frame and a copper sulfate plating bath was used to form a thick copper plating layer (thick film copper layer) having a thickness of 5 μm. Each of the thick metallized polyimide films was obtained by heat treatment for 10 minutes.

Each metal thin film layer-forming metallized film obtained from each film was judged by the average value of the degree of warpage of each of the five sheets. In each film, the average value of warpage exceeding 10% was evaluated as “x”, the film having a warpage exceeding 7% and up to 10% was evaluated as Δ, the film having 5-7% was evaluated as “◯”, and the film having less than 5% was evaluated as “◎”.
As a result, IF real-1, IF real-2 and IF real-4 are all ◎, IF real-5 is ◯, IF real-3, IF real-6 is △, IF ratio-1, IF ratio-2, The IF ratio-3 was all x.
Furthermore, each thick film metallized polyimide film obtained was used, photoresist: FR-200, manufactured by Shipley Co., Ltd. was applied and dried, and then closely exposed with a glass photomask, and further developed with a 1.2 mass% KOH aqueous solution. did. Next, all layers (conductor metal layer; also referred to as conductor metal) formed on the film at 40 ° C. and 2 kgf / cm ² spray pressure in an etching line of cupric chloride containing HCl and hydrogen peroxide. A portion of was etched to form a test pattern, and then electroless tin plating was performed to a thickness of 0.5 μm. Thereafter, annealing was performed at 125 ° C. for 1 hour, and a model substrate having a wiring pattern and an electrode pad for flip chip mounting was obtained from each thick film metallized film.
Further, a model chip was flip-chip mounted on the obtained model substrate.
The wiring pattern from each IF actual-1, IF actual-2, IF actual-3, IF actual-4, IF actual-5, and IF actual-6 shows no peeling of the conductor metal pattern and no warping However, in the wiring patterns from IF ratio-1, IF ratio-2, and IF ratio-3, peeling of the conductor metal pattern was seen and warped.
In addition, in the model chip mounted on the model board obtained from each IF actual-1, IF actual-2, IF actual-3, IF actual-4, IF actual-5, and IF actual-6, the total number of contacts is 512. There were no joint failures at the two locations, but at IF ratio-1, 3 out of 512 locations, IF ratio-2, 7 out of 512 locations, and IF ratio-3, 24 out of 512 locations.

(Examples 7-12, Comparative Examples 4-6)
Using each of the six films obtained in the production examples, the same plasma treatment as in Examples 1 to 6 and Comparative Examples 1 to 3 was performed on the front and back of the film. Next, the film after the plasma treatment is set in a vacuum apparatus having the same sputtering area, and a condition of frequency 13.56 MHz, output 400 W, gas pressure 0.8 Pa, a nickel-chromium (chromium 7%) target, xenon. A 150-mm nickel-chromium alloy underlayer was formed by RF sputtering in an atmosphere. Next, a 3000 angstrom copper thin film layer was formed by sputtering using a copper target. Furthermore, the film was set upside down, and the same treatment was applied to the back side to obtain a metal thin film layer-formed metallized film that was metallized on both the front and back sides.
The obtained double-sided metal thin film layer-formed metallized film was cut into a size of 200 mm × 200 mm, a through hole was formed in a predetermined place with a YAG laser, and then subjected to activation after applying a normal silver chloride / palladium chloride catalyst, Electroless copper plating film is formed on the through hole and metallized surface by wet electroless copper plating, and then panel plating is performed until the copper conductor layer thickness becomes 4.5 μm by copper sulfate plating in a state of being fixed to a plastic frame. Each thick film metallized film was obtained.

Each metal thin film layer-forming metallized film obtained from each film was judged by the average value of the degree of warpage of each of the five sheets. In each film, the average value of the warp degree exceeds 10%, x, the warp degree exceeding 7% to 10%, Δ, 5-7%, and less than 5%.
As a result, IF real-1, IF real-2 and IF real-4 are all ◎, IF real-5 is ◯, IF real-3, IF real-6 is △, IF ratio-1, IF ratio-2, The IF ratio-3 was all x.
Each thick film metallized film after panel plating was subjected to double-sided fine wire processing of line width / line spacing = 7/7 μm. Specifically, photoresist: FR-200, manufactured by Shipley Co., Ltd. was applied and dried, then contacted with a glass photomask, and further developed with a 1.2% KOH aqueous solution. Next, etching was performed with a cupric chloride etching line containing HCl and hydrogen peroxide at a spray pressure of 40 ° C. and 2 kgf / cm ² , and the resist was stripped after the etching to obtain each double-sided circuit pattern.
Each double-sided circuit pattern from IF actual-1 to IF actual-6 has a slightly finer dimension than the negative, is processed with little variation, and does not warp with no pattern peeling. However, in each of the double-sided circuit patterns having an IF ratio of −1 to an IF ratio of −3, the variation in line width was large, pattern peeling was observed, and warping was also observed.

(Examples 13-18, Comparative Examples 7-9)
Six each of the polyimide films obtained in the production examples were cut into a 25 cm × 25 cm square and fixed by being sandwiched between stainless steel frames having an opening with a diameter of 24 cm. Next, plasma treatment of the film surface was performed. The plasma treatment conditions were a xenon gas, a frequency of 13.56 MHz, an output of 100 W, a gas pressure of 0.8 Pa, a treatment temperature of 25 ° C., and a treatment time of 5 minutes. Next, a thickness of 13.56 MHz, an output of 400 W, a gas pressure of 0.8 Pa, a nickel-chromium (3 mass%) alloy target, and a thickness of 10 mm / sec by RF sputtering under a xenon atmosphere. A 50-mm nickel-chromium alloy underlayer was formed. Next, the temperature of the substrate was raised to 250 ° C., and copper was vapor-deposited at a rate of 100 Å / sec to form a copper thin film layer having a thickness of 0.5 μm, thereby obtaining each thin film layer forming metallized film.
Each thin film layer-forming metallized film obtained from each film was determined by the average value of the degree of warpage of each of the five sheets. In each film, the average value of the warp degree exceeds 10%, x, the warp degree exceeding 7% to 10%, Δ, 5-7%, and less than 5%.
As a result, IF real-1, IF real-2 and IF real-4 are all ◎, IF real-5 is ◯, IF real-3, IF real-6 is △, IF ratio-1, IF ratio-2, The IF ratio-3 was all x.
Each thin film layer-forming metallized film obtained was fixed to a plastic frame, and a thick copper plating layer having a thickness of 10 μm was formed using a copper sulfate plating bath, followed by heat treatment at 300 ° C. for 10 minutes, Each thick film metallized polyimide film was obtained.

Using each thick film metallized polyimide film from the same polyimide film obtained, a multilayer printed wiring board by a batch lamination method was produced.
On the opposite surface on which the copper plating layer was formed, an adhesive was applied to a dry film thickness of 12 μm and dried. A YAG laser is used for forming the via hole, and the via diameter is 150 μm. A copper sulfate bath was used for via fill plating, and a tin-copper-silver alloy plating was used for solder plating. Further, a UV curable etching resist ink was used to protect the copper plating layer during via fill and solder bump formation. For pattern formation, photoresist: FR-200, manufactured by Shipley Co., Ltd. was used. After the resist was applied and dried, it was closely exposed with a glass photomask, further developed with a 1.2 mass% KOH aqueous solution, and then with HCl. Etching was carried out with a cupric chloride etching line containing hydrogen oxide at a spray pressure of 40 ° C. and 2 kgf / cm ² . Six layers of the substrates after pattern formation were overlaid, and 18 μm-thick low profile electrolytic copper foil was used as the outermost layer, and pressure adhesion was performed by a vacuum press. Thereafter, patterning of the outermost layer was performed to obtain a multilayer wiring board having seven conductor layers including the outermost layer.
In the multilayer wiring board from the polyimide film of IF actual-1 to IF actual-6, all the patterns were not peeled off, but in the multilayer wiring board from the polyimide film of IF ratio-1 to IF ratio-3 The pattern was peeled off.

(Examples 19 and 20, Comparative Examples 10 to 15)
The polyimide film obtained in IF Example- 1 of Production Example A and IF Example-4 of Production Example B was rolled up into a roll under various conditions shown in Table 1 to obtain a film roll. Table 1 shows the film characteristics of the roll film. Next, the polyimide film was unwound from the film roll and first slit into a width of 250 mm. Next, the film was set in a roll-to-roll type plasma surface treatment apparatus, and the surface of the polyimide film was treated with oxygen glow discharge, and then wound into a roll. The processing conditions are O ₂ gas pressure 2 × 10 ⁻³ Torr, flow rate 50 SCCM, discharge frequency 13.56 MHz, output 250 W, processing time is film feed rate 0.1 m / min and effective plasma irradiation width is about 10 cm. One plasma irradiation time is 1 minute. Thereafter, the film is taken out from the surface treatment apparatus and set in a roll-to-roll type sputtering thin film forming apparatus, and a thickness of 10 nm is formed by DC magnetron sputtering with argon gas using a Ni target and a Cr target on one surface on the inner side of the film. A Ni layer of 5 nm and a Cr layer of 5 nm were formed. These two layers serve as the first metal layer. The degree of vacuum at the time of forming the thin film layer is 3 × 10 ⁻³ Torr. Thereafter, as a second metal layer, a copper thin film layer having a thickness of 250 nm was formed immediately by a DC magnetron sputtering method using argon gas with copper as a target, and wound into a roll. The target Cu was 4N purity.

The sputtering device is a roll-to-roll type device, and the surface treatment, Ni layer preparation, Cr layer preparation, Cu layer are sequentially performed while the film is moved from the roll to the unwinding chamber, the sputtering chamber, the preliminary chamber, and the winding chamber. Fabrication takes place, after which it is wound up on a roll.
Each chamber is roughly partitioned by a slit. In the sputtering chamber, the film is in contact with the chill roll, and is cooled by the temperature of the chill roll (−5 degrees), while being close to the unwinding side, one Ni target, one Cr target, and then the metal particles from two Cu targets. A thin film is formed. The width of each target in the film feeding direction is 12 cm. Part of the sputtered particles is mixed before reaching the film, but after Ni is deposited in the film thickness direction, it is partially mixed, but Cr is deposited, and then a Cu thin film is formed. Since the Cr target and the Cu target are separated by 50 cm or more, mixing between the Cr and Cu particles sputtered in vacuum does not occur here.
Next, the film is unwound from a film roll on which a copper thin film is formed by sputtering, and continuously electroplated with copper (film thickness) on the copper thin film using a vertical roll-to-roll type continuous plating apparatus. 8 μm), and after washing with water and drying, a metallized polyimide film roll was obtained by winding in a roll shape so that the metal surface was inside.

The obtained thick film metallized film was cut into 25 cm × 25 cm, and the average value of the warp degree for 5 sheets was determined. The results are shown in Table 1.
In each film, the average value of warpage exceeding 10% was evaluated as “x”, the film having a warpage exceeding 7% and up to 10% was evaluated as Δ, the film having 5-7% was evaluated as “◯”, and the film having less than 5% was evaluated as “◎”.
Furthermore, each thick film metallized polyimide film obtained was used, photoresist: FR-200, manufactured by Shipley Co., Ltd. was applied and dried, and then closely exposed with a glass photomask, and further developed with a 1.2 mass% KOH aqueous solution. did. Next, all layers (conductor metal layer; also referred to as conductor metal) formed on the film at 40 ° C. and 2 kgf / cm ² spray pressure in an etching line of cupric chloride containing HCl and hydrogen peroxide. A portion of was etched to form a test pattern, and then electroless tin plating was performed to a thickness of 0.5 μm. Thereafter, annealing was performed at 125 ° C. for 1 hour, and a model substrate having a wiring pattern and an electrode pad for flip chip mounting was obtained from each thick film metallized film.
Further, a model chip was flip-chip mounted on the obtained model substrate. The results are shown in Table 1.
The wiring pattern for each film (each 5 sheets) was evaluated according to the following evaluation criteria.
5 points: No peeling of the conductor metal pattern, no bonding failure, and no warping.
3 points: There were bonding failures at 2 to 15 out of 512 total contacts.
1 point: There were poor joints at 15 to 30 out of 512 total contacts.

(Examples 21 and 22)
The polyimide film obtained in IF Example- 1 of Production Example A and IF Example-4 of Production Example B was rolled up into a roll under various conditions shown in Table 1 to obtain a film roll. Table 1 shows the film characteristics of the roll film. Next, the polyimide film was unwound from the film roll and first slit into a width of 250 mm. Next, the film was set in a roll-to-roll type plasma surface treatment apparatus, and the surface of the polyimide film was treated with oxygen glow discharge, and then wound into a roll. The processing conditions are O ₂ gas pressure 2 × 10 ⁻³ Torr, flow rate 50 SCCM, discharge frequency 13.56 MHz, output 250 W, processing time is film feed rate 0.1 m / min and effective plasma irradiation width is about 10 cm. One plasma irradiation time is 1 minute. Thereafter, the film is taken out from the surface treatment apparatus, set in a roll-to-roll type sputtering thin film forming apparatus, and a Ni / Cr (80/20 element ratio) alloy target is used for DC with argon gas on one side of the film winding inside. A Ni / CrCr layer having a thickness of 25 nm was formed by magnetron sputtering, and wound into a roll. This layer is used as a sputtering metal underlayer. The degree of vacuum at the time of forming the thin film layer is 3 × 10 ⁻³ Torr.
Each film on which the sputtering base metal layer film was produced was set in a vacuum apparatus having an unwinding apparatus, a winding apparatus, a plasma processing apparatus, and electron beam evaporation. First, the surface of the sputtering underlayer was plasma treated while feeding the film. The plasma treatment conditions are oxygen gas, frequency 13.56 MHz, output 90 W, gas pressure 0.9 Pa, and the temperature during the treatment is not particularly controlled. The residence time in the plasma atmosphere was about 20 seconds. At this time, the oxide layer on the sputtering thin film was removed by the plasma treatment, and the sputtering base metal layer film was not significantly removed.
Next, a copper layer was deposited on the film after the plasma treatment by electron beam evaporation. After evacuating to an ultimate vacuum of 5 × 10 ⁻⁴ Pa, electron beam evaporation was performed to form a 2.8 μm thick copper thin film and wound into a roll.
In the vacuum tank of this apparatus, the base film unwound from the unwinding roll is supplied to the chill roll through the guide roll. Then, this base film is wound up on a winding roll through a guide roll. A hole is provided in the deposition preventing plate. The “crucible” is located at a location facing the chill roll across the hole portion of the high-frequency voltage application electrode and the deposition preventing plate. The evaporation source material filled in the “crucible” is heated to become vapor. The vapor passes through the holes and is deposited on the substrate film on the surface of the chill roll to form a desired thin film.
The same evaluation was made hereinafter. The results are shown in Table 1. Shown in

As described above, the metallized film using the polyimide film having specific physical properties of the present invention as a substrate is excellent in flatness, for example, even when processed into a printed wiring board or the like, warping or Not only does it have no distortion, it is excellent not only in plane maintenance but also in the adhesion of the metal thin film layer. In addition, since uniform lamination processing is performed even when multilayered, display drivers, high-speed computing devices, graphic controllers, high-capacity memory elements, etc. that require warping, small deformation, particularly high-density fine wiring, etc. It is useful as a substrate on which is mounted.
Furthermore, it is also useful for those that form various metal thin film layers by sputtering, ion plating, or dry plating for vapor deposition that uses a film exposed to high temperatures as a base material. It is also useful as a thin film-forming reflective film, a metal thin film multilayer-formed antireflection film, a metal thin film multilayer-formed specific wavelength transmission film, and the like.

It is the schematic diagram which showed the measuring method (and curvature degree measuring method) of the curl degree of a polyimide film. (A) is a top view, (b) is a sectional view indicated by aa in (a) before hot air treatment, and (c) is indicated by aa in (a) after hot air treatment. It is sectional drawing.

Explanation of symbols

1 Polyimide film specimen 2 Alumina ceramic plate

Claims (16)

A polyimide film obtained by reacting an aromatic diamine and an aromatic tetracarboxylic acid, wherein the polyimide is at least a residue of a pyromellitic acid residue as a residue of an aromatic tetracarboxylic acid and a residue of an aromatic diamine A film having a diaminodiphenyl ether residue and obtained by drying a coating film under a condition where the atmospheric temperature on the opposite side is 1 to 55 ° C. higher than the atmospheric temperature on the upper side of the coating film on the support in the drying step . A metallized polyimide film comprising a polyimide film having a curl degree of 10% or less after heat treatment at 300 ° C. as a base film, and a metal thin film layer formed on at least one side of the base film.   The metallized polyimide film according to claim 1, wherein the curl degree after the heat treatment at 300 ° C. of the film is 8% or less.   3. The metallized polyimide according to claim 1, further comprising a biphenyltetracarboxylic acid residue as an aromatic tetracarboxylic acid residue and a p-phenylenediamine residue as an aromatic diamine residue. the film.   4. A metallized polyimide film according to claim 1, wherein the metal thin film layer is formed by a dry plating method.   The metallized polyimide film according to any one of claims 1 to 4, wherein a metal thin film layer is formed on at least one surface of the base film via a base layer.   A metallized polyimide film comprising a metal thin film layer according to any one of claims 1 to 5 and a thick metal layer laminated thereon.   The metallized polyimide film according to claim 6, wherein the thick film metal layer is formed by a wet plating method. A solution comprising at least a pyromellitic acid residue as an aromatic tetracarboxylic acid residue and a diaminodiphenyl ether residue as a residue of an aromatic diamine and a solvent is formed on the support, and then on the support. The coating film is dried under the condition that the atmospheric temperature on the opposite side is 1 to 55 ° C. higher than the atmospheric temperature on the upper side of the coating film, and then subjected to heat treatment to form a polyimide film. A method for producing a metallized polyimide film, comprising forming a metal thin film layer on at least one surface of a material film.   A flexible printed wiring board obtained by partially removing the metal layer of the metallized polyimide film according to claim 1.   A flexible printed wiring board, wherein a semiconductor chip is directly mounted on the flexible printed wiring board according to claim 9. A polyimide film obtained by reacting an aromatic diamine with an aromatic tetracarboxylic acid, wherein the polyimide is at least a residue of an aromatic tetracarboxylic acid, a biphenyltetracarboxylic acid residue, a residue of an aromatic diamine From the polyimide film obtained by drying the coating film under a condition where the atmospheric temperature on the opposite side is 1 to 55 ° C. higher than the atmospheric temperature on the upper side of the coating film on the support in the drying step having a phenylenediamine residue as A polyimide film having a degree of curl after heat treatment at 300 ° C. of the film of 10% or less and a coefficient of variation (CV%) of the linear expansion coefficient of the film of 25% or less is used as the substrate film, A metallized polyimide film roll comprising a metal thin film layer formed on at least one surface of a film   The metallized polyimide film roll according to claim 11, wherein the difference between the maximum value and the minimum value of the degree of warpage in each part is 5% or less.   The metallized polyimide film roll according to claim 11, wherein the metal thin film layer is formed by a dry plating method.   The metallized polyimide film roll according to any one of claims 11 to 13, wherein a metal thin film layer is formed on at least one surface of the base film via an underlayer.   A metallized polyimide film roll, comprising a metal thin film layer according to any one of claims 11 to 14 and a thick film metal layer further laminated thereon.   The metallized polyimide film roll according to claim 15, wherein the thick metal layer is formed by a wet plating method.

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