JP3912619B2 - Adhesive sheet, metal laminate sheet and printed wiring board - Google Patents

Description

  The present invention relates to an adhesive sheet used for forming an insulating layer in a printed wiring board or the like used for an electronic device, a flexible printed wiring board or the like for reducing the size and weight of a component, and a metal foil for the adhesive sheet. The present invention relates to a laminated metal laminated sheet and a printed wiring board obtained by processing the metal laminated sheet. More specifically, the present invention relates to an adhesive sheet for a flexible printed wiring board and a metal laminate sheet used in TAB, COF, PGA and the like in semiconductor packaging and the like. More particularly, the present invention relates to a metal laminated sheet after metal lamination and a printed wiring board obtained by processing the metal laminated sheet, and a metal laminated sheet and printed wiring board with less warpage and curl.

When an adhesive sheet or an adhesive film is used to form an insulating layer in a printed wiring board or the like, a so-called prepreg in which a glass fiber cloth is impregnated with an uncured epoxy resin or the like has been used. Also, an aramid fiber fabric is used instead of the glass fiber fabric. These prepregs have a thick cloth and cannot meet the demand for lightening in recent years.
In recent years, electronic devices have been improved in functionality, performance, and size, and there is a demand for downsizing and weight reduction of electronic components used therewith. For this reason, multilayer printed wiring boards, semiconductor element packaging methods, and wiring materials or wiring components for mounting them have been required to have higher density, higher functionality, and higher performance. A material excellent in heat resistance, electrical reliability, adhesion, and insulation that can be suitably used as a high-density mounting material such as a semiconductor package, COL and LOC package, MCM, or FPC material such as a multilayer flexible printed wiring board. It has been demanded.
Various proposals have been made in order to achieve reduction in weight (lightness) as a result of forming an insulating layer on a printed wiring board or the like and forming the insulating layer.

It is known that various epoxy resins with relatively high heat resistance are used as the insulation layer, but the insulation from the meaning that the dielectric loss tangent is larger, such as non-uniformity of the insulation layer due to non-uniform flow and resin contamination. Has the problem of lack of reliability.
In order to solve the above problem, an adhesive film in which a resin from a silicone copolymer polyimide resin and an epoxy resin is provided on a temporary support with an adhesive layer thickness of 50 μm has been proposed (see Patent Document 1). Although this method is also excellent in permeability between circuits (conductors), the above-mentioned problem cannot be solved completely, and a certain thickness of the insulating layer cannot be ensured, and characteristic impedance is not obtained. There is a problem in forming an insulating layer such as a high-frequency circuit board that requires strict security.
It has also been proposed to use a thermoplastic polyimide resin (see Patent Documents 2, 3, and 4).
Furthermore, a film in which an adhesive layer composed of a thermoplastic polyimide and a thermosetting resin is provided on at least one surface of the polyimide film has also been proposed (see Patent Document 5).
Furthermore, the polyimide long film with few curls in 25 degreeC is also proposed by making the ratio of the orientation of a polyimide long film front and back into a predetermined value or less (refer patent document 6).
JP 2003-089784 A JP 2000-143981 A JP 2000-144092 A JP 2003-306649 A JP 2003-011308 A JP 2000-085007 A

  The use of a base film made of a conventionally known polyimide film or polyimide benzoxazole film is inferior in heat resistance compared to the use of a base material made of ceramic, and warping and distortion occur when electronic parts are formed due to physical properties in the film. There was a problem that it was easy. 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 of the occurrence of curling due to the existing strain 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.

  The present invention provides an adhesive sheet using a polyimide film having excellent flatness and homogeneity suitable as a base material for electronic parts, and having excellent heat resistance with little warping and curling even when subjected to high temperature treatment, It aims at providing the metal lamination sheet which laminated | stacked metal foil on the adhesive sheet, and the printed wiring board which carried out circuit processing of this metal lamination sheet.

As a result of intensive studies, the present inventors have found that a polyimide film having a curl degree of 10% or less at a specific 300 ° C. is an adhesive sheet, a metal laminate sheet, FPC (flexible printed wiring board), TAB tape, COF tape film, etc. The present invention was completed by finding that high-quality and uniform FPC (Flexible Printed Wiring Board), TAB tape, and COF tape film can be obtained when used as a substrate film.
That is, this invention consists of the following structures.
1. 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 A film obtained by drying a coating film under a condition that has a phenylenediamine residue as the above and 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 An adhesive sheet comprising a polyimide film having a curl degree of 10% or less after heat treatment at 300 ° C. as a base film, and a thermosetting adhesive layer formed on at least one side of the base film.
2. 2. The adhesive sheet according to 1 above, wherein the curl degree after heat treatment at 300 ° C. of the film is 8% or less.
3. 3. A metal laminate sheet, wherein a metal foil is laminated on the thermosetting adhesive layer side of the adhesive sheet according to any one of the above items 1 and 2.
4). A printed wiring board obtained by removing a part of the metal foil of the metal laminate sheet according to the above item 3.
5. 5. A multilayer printed wiring board comprising a plurality of the printed wiring boards according to 4 above laminated.
6). A printed wiring board comprising a semiconductor chip mounted on the printed wiring board according to any one of the above 4 or 5.
7). 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 A film obtained by drying a coating film under a condition that has a phenylenediamine residue as the above and 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 An adhesive sheet roll comprising: a polyimide film having a curl degree after heat treatment at 300 ° C. of 10% or less as a base film, and a thermosetting adhesive layer formed on at least one side of the base film.
8. The adhesive sheet roll as described in 7 above, wherein the base film is a polyimide film having a curl degree of 8% or less after heat treatment at 300 ° C.
9. 9. The adhesive sheet roll according to 7 or 8 above, which has a width of 238 to 516 mm and a length of 5 to 1020 m.
10. A metal laminate sheet roll, wherein a metal foil is laminated on the thermosetting adhesive layer side of the adhesive sheet according to any one of 7 to 9 above.
11. A roll for a printed wiring board, wherein a part of the metal foil of the metal laminate sheet described in 10 above is removed.
12 A roll for a multilayer printed wiring board, wherein a plurality of the printed wiring boards according to the above 11 are laminated.
13. 13. A printed wiring board roll, wherein a semiconductor chip is mounted on the printed wiring board according to 11 or 12 above.
14 A solution comprising at least a biphenyltetracarboxylic acid residue as an aromatic tetracarboxylic acid residue, a phenylenediamine residue as an aromatic diamine residue and a solvent is formed on a support, and then the support The coating film is dried under a condition that the atmospheric temperature on the opposite side is higher by 1 to 55 ° C. than the atmospheric temperature on the upper side of the upper coating film, followed by heat treatment to form a polyimide film, and the polyimide film as a base film, A method for producing an adhesive sheet, comprising forming a thermosetting adhesive layer on at least one surface of the base film.

The adhesive sheet, the metal laminate sheet, and the printed wiring board using the polyimide film in the present invention as a base film, for example, in a printed wiring board, form a metal foil layer on one or both sides of the polyimide film, and this metal foil layer Is removed, and a wiring pattern having a line width of 5 to 30 μm, a line spacing of 5 to 30 μm, and a thickness of about 3 to 40 μm is formed.
The heat treatment at the time of laminating this metal foil layer affects the base film, and when the various physical properties difference between the front and back surfaces of the polyimide film, especially when the curl degree after 300 ° C. heat treatment of the film is below a certain level, Polyimide film is hardly warped or distorted when subjected to high-temperature processing, and as a result, the quality of the obtained printed wiring board is improved and the yield is also improved. Flatness can be maintained even for high-temperature treatment such as these, and as a result, the yield of these products is improved.
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 adhesive sheet, the metal laminate sheet and the printed wiring board using the specific polyimide film of the present invention are used as electronic parts exposed to high temperatures, and the substrate is not easily warped or distorted at the time of production. This makes it possible to realize the manufacture of electronic components and improve the yield, and is extremely significant in industry.

  The substrate film in the present invention is a polyimide film obtained by reacting an aromatic diamine and an aromatic tetracarboxylic acid, and the polyimide is a biphenyltetracarboxylic acid residue as a residue of at least the aromatic tetracarboxylic acid. The first characteristic is that it has a phenylenediamine residue as a residue of aromatic diamines, and the curl degree of the film after 300 ° C. heat treatment 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
The curl degree after 300 ° C. heat treatment of the polyiminess film used as the base film in the present invention is more preferably 8% or less, and further preferably 5% or less.

In the present invention, a biphenyltetracarboxylic acid residue is a bond in a polyamic acid or polyimide formed by a reaction with an aromatic diamine from a functional derivative such as an acid, anhydride, or halide of biphenyltetracarboxylic acid. This is a residue derived from biphenyltetracarboxylic acid. A phenylenediamine residue refers to a residue derived from phenylenediamine in a bond in polyamic acid or polyimide formed by reaction of phenylenediamine with 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 biphenyltetracarboxylic as a residue of at least the aromatic tetracarboxylic acid. It has a phenylenediamine residue as an acid 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, phenylenediamine is a preferred diamine. Examples thereof include p-phenylenediamine, o-phenylenediamine, m-phenylenediamine, and the like, preferably p-phenylenediamine.
As a preferred embodiment, other aromatic diamines can be preferably used in addition to these phenylenediamines. Furthermore, in addition to these aromatic diamines, diamines may be appropriately selected and used.

In the present invention, among the aromatic tetracarboxylic acids, biphenyltetracarboxylic acids (biphenyltetracarboxylic acid and its dianhydride (PMDA) and their lower alcohol esters) are preferred. Among these, 3,3 ′, 4,4′-biphenyltetracarboxylic acid or its dianhydride is more preferable.
As a preferred embodiment, in addition to biphenyltetracarboxylic acid, other aromatic tetracarboxylic acids, preferably pyromellitic acids can be used. Furthermore, in addition to these aromatic tetracarboxylic acids, other aromatic tetracarboxylic acids may be appropriately selected and used.
In the present invention, the phenylene diamines are 50 to 100 mol% based on the wholly aromatic diamines, and the other aromatic diamines are 0 to 50 mol% based on the wholly aromatic diamines. It is preferable to use 0-50 mol% of diamines with respect to wholly 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, biphenyltetracarboxylic acid is 50 to 100 mol% with respect to the wholly aromatic tetracarboxylic acid, pyromellitic acid is 0 to 50 mol% with respect to the wholly aromatic tetracarboxylic acid, and other aromatic tetracarboxylic acids. Is preferably used in an amount of 0 to 50 mol% based on 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.

  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 as a base material for 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 method for producing a polyimide film having a curl degree of 10% or less after 300 ° C. heat treatment used in the present invention is not particularly limited, but as a preferred production example, one of polyimide precursor films (green films) is used. to produce a side polyimide precursor and imidization IM _B imidization ratio IM _a and another one side (B side) satisfies the following formula (a side) film (green film), followed Examples include imidizing the polyimide precursor film (green film).
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 in the width direction at any point on the film (1/3 and 2/3 of the width), and the measured value is the average value of the two 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.
Further, the winding tension is 100N or more, preferably 150N or more and 500N or less.
The diameter of the winding core is desirably 75 mm or more. If it is less than 75 mm, it becomes a factor that inhibits curl improvement. Preferably it is 75-350 mm, More preferably, it is 80-180 mm. Here, the winding core diameter is the outer diameter. When the winding core diameter exceeds this range, handling becomes difficult. On the other hand, if the winding core diameter is less than this range, the bending stress applied to the film becomes large, causing warping and lowering of flatness such as torsion. Furthermore, if the core falls below this range, wrinkles tend to occur when the film during storage expands and contracts due to changes in temperature and humidity, and tends to be inferior in flatness and quality.
In addition, when performing imidation of a green film off-line, the method of winding up so that the said green film may become inside (a support body is outside) is employable.

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.

In the adhesive sheet, metal laminate sheet, and printed wiring board of the present invention, basically, polyimide is at least a biphenyltetracarboxylic acid residue as an aromatic tetracarboxylic acid residue, and a phenylenediamine residue as an aromatic diamine residue. And a polyimide film (F) having a curl degree after heat treatment at 300 ° C. of 10% or less, preferably 8% or less is used as a substrate, and the adhesive sheet has at least one surface of the substrate film. A thermosetting adhesive layer is formed and laminated, and in a metal laminated sheet, a metal laminated sheet in which a metal foil is laminated on the thermosetting adhesive layer side. In a printed wiring board, a metal laminated sheet This is a printed wiring board with a circuit pattern formed by etching away unnecessary portions of the metal foil. Line plate is a multilayer printed wiring board in which a plurality of stacked, also one in which semiconductor chips are mounted directly to these printed circuit boards.
Furthermore, the adhesive sheet of the present invention can be used for forming an insulating layer between printed wiring boards.
Furthermore, the adhesive sheet of the present invention can be used for forming an insulating layer between printed wiring boards.
As the adhesive sheet of the present invention, one having a width of 238 to 516 mm and a length of 5 to 1020 m can be adopted. The width of the adhesive sheet is preferably 256 mm to 508 mm, more preferably 256 to 460 mm, and still more preferably 268 to 386 mm.
The preferable length of the adhesive sheet is 8 m to 770 m, more preferably 8 m to 620 m, still more preferably 24 m to 480 m, and still more preferably 48 m to 360 m.
If the width of the adhesive sheet exceeds a predetermined range, it is difficult to obtain a uniform coating film thickness. Also, coating is difficult if the width of the adhesive sheet is less than the predetermined range.
If the length of the adhesive sheet exceeds a predetermined range, the adhesive sheet roll may be deformed by its own weight. Moreover, if the length of the adhesive sheet is less than the predetermined range, continuous operability by rolling cannot be exhibited.
In the present invention, the core for winding up the film and the adhesive sheet may be a core generally called a 3 inch tube or a 6 inch tube. Considering handling in a clean room, a resin core is preferable instead of a paper core. In the present invention, it is preferable to use a plastic pipe having an inner diameter of 6 inches and a thickness of 5 mm or more, preferably 8 mm or more. If the core diameter is less than 3 inches, permanent distortion may occur in the film, and correction in a subsequent process may be difficult.

The thermosetting adhesive used in the present invention is not particularly limited as long as it is thermosetting and has excellent heat resistance and adhesiveness, but the tensile elastic modulus of the adhesive is that of the base material. It is preferably smaller than the tensile elastic modulus. The tensile modulus of the adhesive / the tensile modulus of the substrate (ratio of the tensile modulus) is preferably 0.01 to 0.5, more preferably 0.3 or less, and particularly preferably 0.1 or less.
If the tensile modulus of the thermosetting adhesive is higher than that of the base film, the stress strain of the base film and the metal foil with different linear expansion coefficients cannot be relaxed and absorbed by the adhesive layer. Since connection reliability with the metal foil layer is not expressed, it is not preferable.
As the thermosetting adhesive used in the present invention, epoxy-based, urethane-based, acrylic-based, silicone-based, polyester-based, imide-based, polyamide-imide-based, etc. can be used, and more specifically, for example, mainly a polyamide resin. Examples thereof include those containing a flexible resin such as phenol and a hard material such as phenol as main components and containing an epoxy resin and imidazoles. More specifically, dimer acid-based polyamideimide resin, room temperature solid phenol, room temperature liquid epoxy and the like can be exemplified, having moderate softness, hardness, adhesiveness, etc. The semi-cured state can be easily controlled. Further, as the polyamideimide resin, those having a weight average molecular weight of 5,000 to 100,000 are suitable. Furthermore, since the cohesive force of the amideimide resin also changes depending on the carboxylic acid and amine of the polyamideimide resin raw material, it is preferable to select the molecular weight, softening point, etc. of the phenol or epoxy resin as appropriate. Moreover, a polyamide resin, a polyester resin, an acrylonitrile butadiene resin, a polyimide resin, a butyral resin, or the like can be used instead of the polyamideimide resin. Furthermore, these silicone-modified materials and the like are more preferable because they exhibit flexibility.

In addition to phenolic resins and epoxy resins, maleimide resins, resole resins, triazine resins and the like can also be used. Nitrile butadiene rubber can also be blended and copolymerized.
The thermosetting adhesive of the present invention is controlled in a cured state to a semi-cured state, as a method for controlling the cured state, for example, heating with hot air when applying and drying the adhesive on the substrate, Heating with far / near infrared rays, electron beam irradiation and the like can be mentioned. In the control by heating, it is preferable to heat at 100 to 200 ° C. for 1 to 60 minutes, more preferably at 130 to 160 ° C. for 5 to 10 minutes. Further, in a state where the TAB tape is wound in a roll shape, the cured state can be controlled by heat treatment at a relatively low temperature of, for example, about 40 to 90 ° C. for several hours to several hundred hours. The conditions for controlling the cured state are preferably determined in consideration of the composition of the adhesive, the curing mechanism, and the curing rate. In this way, it is possible to obtain a semi-cured adhesive by controlling the cured state. The thermosetting adhesive of the present invention is used once in a semi-cured state.
Here, the semi-cured state is a solid phase state that can be softened or melted by heating and finally cured. The thermosetting adhesive of the present invention basically includes a component that imparts flexibility and a component that imparts heat resistance so that a semi-cured state can be maintained.

Note that plasma treatment, corona treatment, and alkali treatment of the polyimide film surface before applying the thermosetting adhesive is a preferable method for increasing the adhesive force, and such plasma is an inert gas plasma. Nitrogen gas, Ne, Ar, Kr, or Xe is used as the active 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.
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 base film surface may fall.

Next, a thermosetting adhesive layer is formed on the surface-treated polyimide film surface, but the method is not limited, and a thermosetting adhesive is applied to the polyimide film surface and dried to form a thermosetting adhesive. A method for forming the adhesive layer, or a thermosetting adhesive layer on the polyimide film surface by forming a thermosetting adhesive layer in advance on another release sheet or film and pasting or transferring it to the polyimide film surface. An example is a method of forming a layer.
The polyimide film with an adhesive layer thus obtained can be used as a die bonding tape or a lead-on-chip film.
In the lamination of the metal foil, the metal foil is laminated on the thermosetting adhesive layer formed on the polyimide film surface with or without the plasma treatment and laminated using pressure, heat, or the like.
The metal as the metal foil of the present invention is silver, copper, gold, platinum, rhodium, nickel, aluminum, iron, chromium, zinc, tin, brass, bronze, bronze, monel, tin lead solder, tin copper solder, Tin-silver solder or the like alone or an alloy thereof is used, but using copper is a preferred embodiment in terms of balance between performance and economy. When the metal foil layer is used for a circuit (conductive), the thickness of the metal layer is preferably 1 to 175 μm, more preferably 3 to 50 μm. When using the polyimide film which bonded the metal foil layer as a heat sink, the thickness of a metal layer becomes like this. Preferably it is 50-3000 micrometers.

Although the surface roughness of the polyimide film surface laminated through the thermosetting adhesive layer of the metal foil layer is not particularly limited, the centerline average roughness in JIS B 0601 (definition and display of surface roughness) It is preferable that the values represented by (hereinafter referred to as Ra) and ten-point average roughness (hereinafter referred to as Rz) are 0.1 μm or less for Ra and 1.0 μm or less for Rz.
In this invention, it is a preferable aspect that the metal laminated sheet which is a composite_body | complex of the polyimide film and metal foil obtained by the said method is further heat-processed at 200-350 degreeC. 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 deteriorates, which is not preferable.

The thus obtained metal laminated sheet of the present invention is coated with a photoresist on the side of a conductive metal foil layer or a later thick film metal layer formed on the conductive metal foil layer, if necessary. After drying, a wiring circuit pattern is formed by the steps of exposure, development, etching, and photoresist stripping. Further, if necessary, solder resist coating, curing and electroless tin plating are performed to form a flexible printed wiring board and multilayering them. A multilayer printed wiring board or a printed wiring board on which a semiconductor chip is directly mounted can be obtained. There are no particular limitations on the method for creating these circuits, making them multi-layered, and mounting a semiconductor chip, and the methods may be appropriately selected from known methods.
In the present invention, when manufacturing a so-called TAB tape having a flying lead, a device hole is secured by pre-punching an adhesive sheet coated with an adhesive in advance, and then laminated with a copper foil, A conductor pattern including a flying lead can be formed according to a conventional method.
On the surface of the metal (foil) layer used in the present invention or, if necessary, the thick film metal layer attached later, an inorganic coating such as a single metal or a metal oxide may be formed. Good. In addition, the surface of the metal foil layer or the post-attached thick film metal layer formed on the metal foil layer, if necessary, is treated with a coupling agent (aminosilane, epoxysilane, etc.), sand plast treatment, rolling treatment, corona treatment, You may use for a plasma process, an etching process, etc.

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 measurement of the curl degree after 300 degreeC heat processing and the measurement of imidation rate are as above-mentioned method.
1. The thickness of the polyimide film was measured using a micrometer (Finereuf, Millitron (registered trademark) 1245D).
2. Warpage of various sheets (apparent warpage)
As shown in FIG. 1 (C), test pieces of various sheets of 50 mm × 50 mm are left to be concave on the plane, and distances from the four corner planes (h1, h2, h3, h4: unit mm). Is the 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.
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 sample pieces is performed at 2 points in the width direction and length direction of each sheet (in principle, the points from 1/3 and 2/3 of the width are taken, and if not possible, the points are taken from the center as much as possible) It shall be expressed as the average value of 4 points.

Abbreviations of compounds used in Examples and the like are described below.
P-PDA: paraphenylenediamine BPDA: 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride DMF: dimethylformamide DMAC: dimethylacetamide AA: acetic anhydride IQ: isoquinoline In addition, the abbreviation GF is a polyimide precursor film (Green film), the abbreviation IF indicates a polyimide film.

(Production example: 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 P-PDA was added. Next, after DMAC is added and completely dissolved, BPDA is added, and P-PDA and BPDA as monomers are polymerized in DMAC at a molar ratio of 1/1, and 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 (Toyobo Co., Ltd.) having a thickness of 188 microns and a width of 800 mm. )) Coated on the non-lubricating surface to a width of 740 mm (squeegee / belt gap is 430 μm)
It dried by passing through the continuous drying furnace which has 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.
[Drying conditions A]
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 air volume 15 cubic m / min, lower air volume 20 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.

GF (polyamic acid film) that became self-supporting after drying was peeled from the polyester film to obtain each GF, real-1, real-2, and real-3. | IM _A -IM _{B of} each GF The values of | were 0.6, 1.0, and 3.7, respectively.
Each GF (green film) obtained was passed through a continuous heat treatment furnace purged with nitrogen while holding both ends with a pin tenter, the first stage was 180 ° C. for 5 minutes, and the heating rate was 4 ° C./second. The temperature was raised, and the second stage was heated at 400 ° C. for 5 minutes as a second stage to proceed the imidization reaction. Then, each polyimide film (IF), F real-1, F real-2, F real-3 which exhibits brown was obtained by cooling to room temperature in 5 minutes.
In addition, when heat-treating GF, 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 IF (polyimide film) obtained were 15 μm and 2.6% for F real-1, 15.1 μm and 3.9% for F real-2, and 15 μm and 7 for F real-3. 3%.

(Production Example; Real-4 to Real-6)
A container equipped with a nitrogen introduction tube, a thermometer, and a stirring rod was purged with nitrogen, and then P-PDA was added. Next, after DMAC is added and completely dissolved, BPDA is added, and P-PDA and BPDA as monomers are polymerized in DMAC at a molar ratio of 1/1, and the monomer charge concentration becomes 15% by mass. When stirred at 25 ° C. for 5 hours, a brown viscous polyamic acid solution was obtained. The obtained polyamic acid solution was coated on a stainless steel belt (the gap between the squeegee and the belt was 450 μm), and dried in the same manner as in Production Examples: Example-1 to Example-3. GF which became self-supporting after drying was peeled from the stainless steel belt to obtain GF, -4, -5, and -6.
GF (polyamic acid film) that became self-supporting after drying was peeled from the polyester film to obtain each GF, real-1, real-2, and real-3. | IM _A -IM _{B of} each GF The values of | were 1.1, 1.5, and 4.2, respectively.
The obtained GF 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. Under the conditions, two-stage heating was performed to advance the imidization reaction. Then, by cooling to room temperature in 5 minutes, each IF, F real-4, F real-5, and F real-6 of 25 micrometers in thickness which exhibit brown were obtained.
In addition, when heat-treating GF, 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 IF obtained were 15 μm and 4.3% for F real-4, 15.1 μm and 5.5% for F real-5, and 15 μm and 8.3% for F real-6. there were.

(Production example; 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 Example 1, and this is coated on a stainless steel belt (the gap between the squeegee / belt is 430 μm), and production examples; drying was carried out in 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 GF that became self-supporting after drying was peeled from the stainless steel belt to obtain each GF3 type, ratio-1, ratio-2, and ratio-3.
The values of | IM _A −IM _B | of each GF were 5.3, 7.5, and 11.2, respectively.
Each GF 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. As the second stage, two stages of heating were performed at 400 ° C. for 5 minutes to advance the imidization reaction. Then, each IF, F ratio-1, F ratio-2, and F ratio-3 which show brown were obtained by cooling to room temperature in 5 minutes.
The thickness and curl degree of each IF obtained were 15 μm and 10.5% at F ratio-1 of 15.1 μm and 14.1% at F ratio-2, and 15 μm and 18.5% at F ratio-3. there were.

(Examples 1-6, Comparative Examples 1-3)
<Manufacture of adhesive sheet>
Using each polyimide film obtained in the production example, an adhesive sheet was obtained according to the following.
N, N-dimethylacetamide as an organic polar solvent, 1,3-bis (3-aminophenoxy) benzene and 3,3′-dihydroxy-4,4′-diaminobiphenyl as a diamine compound in a molar ratio of 9: 1 A solution of a polyamic acid polymer was obtained using 3,3 ′, 4,4′-ethylene glycol benzoate tetracarboxylic dianhydride as the ester tetracarboxylic acid. This polyamic acid polymer solution was heated under reduced pressure to obtain a thermoplastic polyimide.
80 parts by mass of this thermoplastic polyimide, 100 parts by mass of Epicoat 1032H60 as a thermosetting resin (epoxy resin), 30 parts by mass of 4,4′-diaminodiphenyl ether as a curing agent, and 910 parts by mass of dioxolane as an organic solvent And dissolved by stirring. Thereby, an adhesive solution was obtained.
The obtained adhesive solution was cast on one side of a 12.5 μm-thick releasable polyethylene terephthalate film having a release layer formed on one side, and dried at 60 ° C. for 2 minutes to bond 2.5 μm in thickness. An agent layer was formed.

The obtained film was laminated with the adhesive layer and one side of the polyimide film obtained above, and each single-sided adhesive sheet from each polyimide film (KTS real-1 to KTS real-6 and KTS ratio). -1 to KTS ratio-3; the used polyimide film is displayed at the end of each film obtained in the above production example, KTS real-1 is a single-sided adhesive sheet from F real-1 polyimide film, and so on. Got. The total thickness of the polyimide film and adhesive layer of the obtained adhesive sheet was 17.5 μm.
The two obtained films were laminated with the adhesive layer and both sides of the polyimide film obtained above, and each adhesive sheet from each polyimide film (RYS Real-1 to RYS Real-6 and RYS). Ratio-1 to RYS ratio-3). The total thickness of the polyimide film and adhesive layer of the obtained adhesive sheet was 20 μm.
Judgment was made based on the average value of the degree of warpage of each obtained adhesive sheet. The sheet having an average warpage degree exceeding 10% was evaluated as “x”, the sheet having a warpage degree exceeding 7% and up to 10% was evaluated as “Δ”, and the sheet having 3-7% was evaluated as “◯”.
As a result, KTS real-1, KTS real-2, KTS real-4 are all ◎, KTS real-3, KTS real-5 is ◯, KTS real-6 is △, KTS ratio-1, KTS ratio-2, The KTS ratio-3 was all x.
RYS real-1, RYS real-2, RYS real-3, RYS real-4, RYS real-5 are all ◎, RYS real-6 is ◯, RYS ratio-1 is △, RYS ratio-2, RYS ratio- 3 was x.

<Manufacture of metal laminate sheet>
Each film obtained in the production example was used. First, each polyimide film was slit to a width of 508 mm and subjected to corona treatment. Then, RV50 manufactured by Toyobo Co., Ltd. was applied as an adhesive to the surface of each polyimide film so that the coating thickness was 18 μm, and a dry oven at 80 ° C. And dried for 15 minutes to obtain each adhesive sheet from each polyimide film. Next, the rolled copper foil manufactured by Japan Energy, the bonded surface of BHY-22-T (18 μm) and the adhesive-coated surface of the adhesive sheet were combined, and the roll temperature was 120 ° C. and the feed rate was 60 cm / min with a silicon rubber roller laminator. After laminating and winding, the adhesive is cured by treatment at 150 ° C. for 5 hours in a vacuum dryer, and each metal laminated sheet (KTM Real-1 to KTM Real-6 and KTM from each polyimide film) is cured. Ratio-1 to KTM ratio-3).
Judgment was made by the average value of the degree of warpage of each obtained metal laminated sheet. The average value of warpage in each metal laminated sheet is over 10%, crossover is over 7% and up to 10% is △, 3-7% is ○, less than 3% is ◎. .
As a result, KTM real-1, KTM real-2, KTS real-3, KTM real-4, KTM-5 are all ◎, KTM real-6 is ◯, KTM ratio-1 is △, KTM ratio-2, KTM Ratio-3 was x.

<Manufacture of printed wiring boards>
Each metal laminated sheet (copper-clad laminated film) obtained above was slit to a width of 105 mm, punched with sprocket holes for conveyance and alignment holes at both ends, and set in a continuous machine for COF processing. The following is a normal one-sided circuit processing process, after applying a photoresist on the surface of the rolled copper foil, exposing and developing a predetermined pattern, using the patterned resist as a mask and using an aqueous ferric chloride solution Etching was performed. A liquid resist type solder resist is applied and dried, mask exposure and development are performed while leaving the pad portion, and a 1.5 μm thick tin plating is applied to the pad portion, and a printed wiring board (COF film) from each polyimide film Substrate). The circuit portion with the narrowest line width of each of the obtained COF film substrates has a line width / line spacing = 60/60 μm.
A semiconductor chip is mounted on the obtained film substrate for COF, subjected to a bonding process using flip chip bonding, and then resin-sealed by a potting method to form each semiconductor package (SCJ Real-1 to SCJ Real-6, SCJ ratio-1 to SCJ ratio-3) were produced. The number of contacts between the chip / substrate of each obtained semiconductor package is 256. The package was loaded into an Etak (R) temperature cycle test apparatus (manufactured by Enomoto Kasei Co., Ltd.) and a heating / cooling test was performed. The test was performed by repeatedly heating and cooling between a low temperature of −50 ° C. and a high temperature of 150 ° C. every 30 minutes. The test time was 3000 hours. A continuity test was conducted after the test to determine the defect rate at the connection point.
The defective rate of the connection point was evaluated as ◎ when less than 10 ppm, ◯ when 10-30 ppm, and x when more than 30 ppm.
The evaluation results are as follows: SCJ Real-1, SCJ Real-2, SCJ Real-3, SCJ Real-4, SCJ Real-5 are all ◎, SCJ Real-6 ○, SCJ Ratio-1, SCJ Ratio-2, SCJ. All ratios -3 were x.

(Examples 7-12, Comparative Examples 4-6)
<Manufacture of metal laminate sheet>
Each film obtained in the production example was used. Each polyimide film was first slit to a width of 508 mm and then subjected to corona treatment. Then, RV50 manufactured by Toyobo Co., Ltd. was applied to the surface of each polyimide film as an adhesive so that the coating thickness was 18 μm, and the dry temperature was 80 ° C. It was made to dry for 15 minutes in oven, and each adhesive sheet from each polyimide film was obtained. Next, the adhesive treated surface of the electrolytic copper foil (12 μm) and the adhesive coated surface of the adhesive sheet are combined, laminated with a silicon rubber roller type laminator at a roll temperature of 120 ° C. and a feed rate of 60 cm / min, and wound up Then, the adhesive is cured by treating at 150 ° C. for 5 hours in a vacuum dryer, and each double-sided metal laminated sheet (RYM Real-1 to RYM Real-6 and RYM Ratio-1 to RYM Ratio-3 from each polyimide film) )
Judgment was made by the average value of the degree of warpage of each obtained metal laminated sheet. The average value of warpage in each metal laminated sheet is over 10%, crossover is over 7% and up to 10% is △, 3-7% is ○, less than 3% is ◎. .
As a result, RYM real-1, RYM real-2, RYS real-3, RYM real-4, RYM real-5 are all ◎, RYM real-6 is ◯, RYM ratio-1 is △, RYM ratio-2, The RYM ratio-3 was x.

<Manufacture of printed wiring boards>
A liquid crystal resist is used to form a negative resist having a film thickness of 6 μm on one side of each double-sided metal laminate sheet prepared above, the copper layer is removed by etching, and the LCD includes fine lines having a line spacing / line width of 17 μm / 13 μm. A test circuit pattern of 4.8 cm × 4.8 cm assumed to be mounted on a driver was formed. Similarly, a square pattern of 4 mm square is formed in a lattice pattern with a pattern spacing of 0.5 mm on the back surface, and each test circuit board (TPR actual-1 to TPR actual-6 and TPR ratio −1) from each polyimide film is formed. ˜TPR ratio-3) were prepared in the same manner. The area density of the pattern is 50% on both the front and back sides. Three prepared test circuit boards are prepared, and the adhesive sheets (RYS) in Examples 1 to 6 and Comparative Examples 1 to 3 are prepared between the test circuit boards. -1 to RYS -6 and RYS ratio -1 to RYS ratio -3) and the single-sided adhesive sheets in Examples 1 to 6 and Comparative Examples 1 to 3 at the top and bottom of each test circuit board ( KTS real-1 to KTS real-6 and KTS ratio-1 to KTS ratio-3) are arranged so as to be from the same polyimide film, and are laminated by hot pressing at 150 ° C. to test each of the multilayers. A multilayer substrate was prepared. The obtained multilayer substrate was immersed in a 260 ° C. tin-silver solder bath for 15 seconds, and then the presence or absence of pattern abnormality was observed and evaluated.

In each of the test multilayer substrates from F actual -1 to F actual -6 polyimide films, all patterns were not peeled off, but for each test from polyimide films having F ratio -1 to F ratio -3. In the multilayer substrate, peeling of the pattern was observed.
In addition, for cross-sectional observation, each test multilayer substrate was cut in the direction in which the cross-section in the width direction of the fine line pattern emerges, embedded in resin, polished on the end face, and then magnified with a microscope. In each of the test multilayer substrates from the F actual-1 to F actual-6 polyimide films, which were evaluated for the deformation of the adhesive sheet as shown, all of the adhesive sheets were not deformed, Deformation of the adhesive sheet was observed in each of the test multilayer substrates from the polyimide film having F ratio-1 to F ratio-3.

(Examples 8-9, Comparative Examples 5-7)
(Manufacture of long polyimide film)
A container equipped with a nitrogen introduction tube, a thermometer, and a stirring rod was purged with nitrogen, and then P-PDA was added. Next, after DMAC is added and completely dissolved, BPDA is added, and P-PDA and BPDA as monomers are polymerized in DMAC at a molar ratio of 1/1, and the monomer charge concentration becomes 15% by mass. When stirred at 25 ° C. for 5 hours, a brown viscous polyamic acid solution was obtained.
The obtained polyamic acid solution was used as a dope, defoamed, coated on an endless stainless steel belt (the gap between the squeegee / belt was 400 μm), and dried in the same manner as in Production Example: Real-1. The polyamic acid film that became self-supporting after the drying was peeled off from the stainless steel belt, the width of the thick 49.5Myuemu 700 mm, length 1500 m GF: obtain real -8, of each GF | IM _A -IM The value of _B | was 1.3. The obtained GF was passed through a continuous heat treatment furnace purged with nitrogen as in Production Example 4, and the first stage was at 180 ° C. for 4 minutes, and the heating rate was 3 The temperature was raised at 0 ° C./second, and the second stage was heated at 480 ° C. for 3 minutes under the condition of 3 minutes to proceed the imidization reaction. Then, it is cooled to room temperature in 5 minutes, and the parts used for gripping on both sides are dropped by 50 mm slits, wound around a 6-inch plastic core (outer diameter 168 mm), IF (polyimide film) with a width of 600 mm and a length of 2000 m F real-8 was obtained.
(Long adhesive sheet)
N, N-dimethylacetamide as an organic polar solvent, 1,3-bis (3-aminophenoxy) benzene and 3,3′-dihydroxy-4,4′-diaminobiphenyl as a diamine compound in a molar ratio of 9: 1 A solution of a polyamic acid polymer was obtained using 3,3 ′, 4,4′-ethylene glycol benzoate tetracarboxylic dianhydride as the ester tetracarboxylic acid. This polyamic acid polymer solution was heated under reduced pressure to obtain a thermoplastic polyimide.
80 parts by mass of this thermoplastic polyimide, 100 parts by mass of Epicoat 1032H60 as a thermosetting resin (epoxy resin), 30 parts by mass of 4,4′-diaminodiphenyl ether as a curing agent, and 910 parts by mass of dioxolane as an organic solvent And dissolved by stirring. Thereby, an adhesive solution was obtained.
The obtained adhesive solution was cast on one side of a 12.5 μm-thick releasable polyethylene terephthalate film having a release layer formed on one side, dried at 60 ° C. for 2 minutes, and wound on a 6-inch plastic core. An adhesive layer-formed polyethylene terephthalate film in which an adhesive layer having a width of 600 mm, an effective length of 2000 m, and a thickness of 2.5 μm was formed was obtained.
The polyimide film F real-8 obtained above was set in a roll-to-roll atmospheric pressure plasma apparatus equipped with an unwinding / winding device,
Distance between electrodes 2mm
Electrode width 560mm
Gas flow rate Nitrogen 15 liters / minute, Oxygen 1 liter / minute Power condition 400 watts (150 volts, 2.67 amps) 30 kHz
The surface treatment was performed under the condition of a treatment time of 15 seconds. Next, the processed polyimide film and the adhesive layer of the adhesive layer-formed polyethylene terephthalate film obtained above are laminated and laminated, slit to a predetermined width, and then cut to a predetermined length to bond each side. Sheets (KTS Real-8, KTS Real-9, KTS Ratio-5, KTS Ratio-6, KTS Ratio-7) were obtained. The total thickness of the polyimide film and the adhesive layer of the obtained adhesive sheet was 17.5 μm.
KTS actual -8 width 250mm, length 1000m plastic tube winding diameter 168mm
KTS actual -9 width 508mm, length 1000m plastic tube winding diameter 168mm
KTS ratio-5 width 508mm, length 1000m plastic tube winding diameter 60mm
KTS ratio-6 width 580mm, length 1000m plastic tube winding diameter 168mm
KTS ratio-7 width 508mm, length 1600m plastic tube winding diameter 168mm
The total thickness of the polyimide film and the adhesive layer of the obtained adhesive sheet was 17.5 μm. Table 1 shows the results of evaluating the degree of warpage of the obtained adhesive sheet every 250 m. Shown in In addition, the degree of warp was treated as one unit to be measured from a point every 250 m to a point added by 5 m.

As described above, the adhesive sheet, the metal laminate sheet and the printed wiring board using the polyimide film having specific physical properties of the present invention as a base material are excellent in flatness, and processed into a printed wiring board, for example. Even in this case, there is no warpage or distortion, and not only the flatness is excellent, but also the adhesion of the metal foil layer due to the flatness is excellent.
In addition, since uniform lamination processing is performed even when multilayered, it is suitable for display drivers, high-speed arithmetic devices, graphic controllers, high-capacity memory elements, etc. that require warping, small deformation, particularly high-density fine wiring. It is useful as a substrate to be used. In particular, they are useful as printed circuit boards such as display drivers, high-speed arithmetic devices, graphic controllers, and high-capacity memory devices that are often exposed to high temperatures.

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. However, (c) shows the state which left various sheets stationary at the time of the curvature measurement of various sheets. It is a schematic diagram of the structure of the circuit board for a test before lamination | stacking. It is a schematic diagram of the structure of the circuit board for a test after lamination | stacking.

Explanation of symbols

      1: Test piece of polyimide film, 2: Alumina ceramic plate, 3: Circuit board for test, 4: Adhesive sheet, 5: Copper foil, 6: Circuit side polymer film, 7: Insulation layer width, 8: Adhesive sheet Polymer film, 9: adhesive, 10: deformation of film, 11: void

Claims (14)

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 A film obtained by drying a coating film under a condition that has a phenylenediamine residue as the above and 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 An adhesive sheet comprising a polyimide film having a curl degree of 10% or less after heat treatment at 300 ° C. as a base film, and a thermosetting adhesive layer formed on at least one side of the base film.   The adhesive sheet according to claim 1, wherein the curl degree of the film after heat treatment at 300 ° C is 8% or less.   A metal laminate sheet, wherein a metal foil is laminated on the thermosetting adhesive layer side of the adhesive sheet according to claim 1.   A printed wiring board obtained by partially removing the metal foil of the metal laminate sheet according to claim 3.   A multilayer printed wiring board comprising a plurality of the printed wiring boards according to claim 4 laminated.   A printed wiring board comprising a semiconductor chip mounted on the printed wiring board according to claim 4. 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 A film obtained by drying a coating film under a condition that has a phenylenediamine residue as the above and 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 An adhesive sheet roll comprising: a polyimide film having a curl degree after heat treatment at 300 ° C. of 10% or less as a base film, and a thermosetting adhesive layer formed on at least one side of the base film.   The adhesive sheet roll according to claim 7, wherein a polyimide film having a curl degree after heat treatment at 300 ° C of 8% or less is used as a base film.     The adhesive sheet roll according to claim 7 or 8, wherein the adhesive sheet roll has a width of 238 to 516 mm and a length of 5 to 1020 m.   A metal laminated sheet roll comprising a metal foil laminated on the thermosetting adhesive layer side of the adhesive sheet according to claim 7.   A roll for a printed wiring board, wherein a part of the metal foil of the metal laminate sheet according to claim 10 is removed.   A roll for a multilayer printed wiring board, wherein a plurality of the printed wiring boards according to claim 11 are laminated.   A roll for a printed wiring board, comprising a semiconductor chip mounted on the printed wiring board according to claim 11.   A solution comprising at least a biphenyltetracarboxylic acid residue as an aromatic tetracarboxylic acid residue, a phenylenediamine residue as an aromatic diamine residue and a solvent is formed on a support, and then the support The coating film is dried under conditions where the atmospheric temperature on the opposite side is higher by 1 to 55 ° C. than the atmospheric temperature on the upper side of the upper coating film. A method for producing an adhesive sheet, comprising forming a thermosetting adhesive layer on at least one surface of the base film.

Images