JP2006142545A - Laminated film and printed wiring board using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated film optimum to a flexible printed wiring board, and the printed wiring board using it. <P>SOLUTION: The laminated film is constituted by laminating a layer (B-layer), which comprises copolymerized polyphenylene sulfide containing at least one kind of a copolymer unit other than a p-phenylene sulfide unit and satisfying the formulae 50≤PPSF(B)≤95 and 3≤COPF(B)<50, and a polymer resin layer (C-layer) not substantially having a melting point at least on one side of a biaxially oriented film (A-layer) comprising a resin composition based on poly-p-phenylene sulfide in this order. PPSF(B) is content represented by mol% with respect to the total repeating unit of the p-phenylene sulfide unit in the B-layer and CCPF(B) is content represented by mol% with respect to the total repeating unit of the copolymer unit much contained next to the p-phenylene sulfide unit in the B-layer. Further, the printed wiring board is constituted by forming an electric circuit at least on one side of the surface of the C-layer of the laminated film. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a laminated film using a biaxially oriented poly-p-phenylene sulfide film (hereinafter sometimes abbreviated as “PPS film”). More specifically, it is a laminated film of a PPS film, a copolymerized PPS layer, and a polymer resin layer having substantially no melting point, and particularly based on the laminated film most suitable for an insulating material of a printed wiring board and the laminated film. The present invention relates to a printed wiring board.

  With the development of IT equipment, digital equipment, automotive electronic equipment, etc., demands for heat resistance, high density, thin film, etc. are increasing day by day, and high frequency is expected for communication equipment that is expected to expand in the future. Properties such as properties and low hygroscopicity are also desired. Of these, printed circuit boards (FPC: flexible printed circuit boards) are widely used in various devices, and the above demands for high frequency characteristics and low moisture absorption are strong. In the heat resistance, densification, thinning, etc., polyimide films (hereinafter sometimes abbreviated as PI films) retain their required characteristics and are frequently used. However, in fields that require high-frequency characteristics for communication, the use is restricted because the dielectric characteristics change greatly with respect to high-frequency and the moisture absorption rate is high. Therefore, in fields where high frequency characteristics for communication, low moisture absorption, etc. are desired, liquid layer polymer sheets (hereinafter sometimes abbreviated as LCP sheets) that relatively satisfy the above characteristics are attracting attention. Actually, it has not been adopted in earnest due to problems in thickness unevenness and adhesion, difficulty in circuit processability, and high price.

  On the other hand, high-frequency characteristics and low hygroscopicity (hygroscopic dimensional stability) of biaxially oriented polyphenylene sulfide films have attracted attention and are being studied for FPC and multilayer circuit board materials. A flexible lint wiring board based on the film has already been proposed (see, for example, Patent Document 1). Also, a metal base circuit in which a biaxially oriented PPS film is mainly used for a high frequency circuit board, and an insulating layer is composed only of PPS (a laminate of a PPS film and a metal layer is heat-sealed and laminated via a copolymerized PPS layer). A substrate has also been proposed (see, for example, Patent Document 2). Further, the following is also known in which the film is laminated with another resin layer other than PPS for use as a circuit board material.

  (1) A warp caused by improvement of solder heat resistance or lamination with a conductor layer by providing a resin layer other than PPS such as PI on the surface of the PPS film and controlling the tensile elastic modulus at 150 ° C. within a specific range. Has been proposed (see, for example, Patent Document 3).

  (2) It has been proposed to improve solder heat resistance by laminating a metal compound (metal oxide or the like) layer on the surface of a PPS film (see, for example, Patent Document 4).

(3) It has been proposed that a laminated film obtained by heat-treating the laminated film of (2) above and making it insoluble in 230 ° C. diphenyl ether has improved solder heat resistance and thermal dimensional stability and can be applied to a printed wiring board ( For example, see Patent Document 5).
JP 55-36945 A Japanese Patent Laid-Open No. 06-91812 JP-A 63-237947 Japanese Patent Laid-Open No. 01-2225016 JP-A-01-222951

  However, a conventional printed wiring board using a biaxially oriented PPS film and a laminated film as a base thereof have the following problems, such as heat resistance, high frequency characteristics, low moisture absorption characteristics, flame retardancy, and workability. However, development to circuit boards that are required to have a well-balanced balance has been limited.

  That is, the use of a printed wiring board based on a single PPS film is extremely limited in applications where solder is used because of significant thermal deformation and thermal dimensional change due to soldering at 260 ° C. or higher. In addition, the PPS film, the circuit layer, and the metal layer are laminated with the copolymer PPS, and the metal base circuit board can be laminated without using any resin other than PPS. And low moisture absorption. However, solder heat resistance and thermal dimensional stability cannot be improved. On the other hand, the laminated film of the PPS film (1) for the purpose of improving solder heat resistance is excellent in solder heat resistance and thermal dimensional stability because it is coated with a heat resistant resin such as PI resin. Since the main body is PPS, high frequency characteristics, low hygroscopicity, etc. are maintained. However, since the adhesion between the PPS film layer and the surface resin layer is weak, the adhesion with the circuit layer is poor. This causes serious problems that the circuit width becomes narrow and the circuit and the base film peel off in a high-density circuit. In addition, the laminated film (2) cannot be improved in solder heat resistance and thermal dimensional stability unless it is heat-treated at a temperature of about 200 ° C. for a long time after being processed into a circuit board. Since the compound layer is soft and easily scraped off, the adhesion of the layer is weak. This makes it difficult to perform processing such as circuit formation. The laminated film (3) is excellent in soldering heat resistance and thermal dimensional stability, but the heat treatment conditions (high temperature temperature in the presence of oxygen, long time) of the metal compound layer laminated on the film surface are severe and practical. The problem was that it was not suitable, and the range of use was considerably limited.

  Therefore, in view of the above problems, the present invention retains the excellent properties of the PPS film such as high frequency stability of dielectric properties, low moisture absorption, flame retardancy, mechanical properties, solder heat resistance, thermal dimensional stability, It is an object of the present invention to provide a laminated film that is particularly suitable for a flexible printed wiring board for high frequency use, and a printed wiring board based on the laminated film, provided with adhesion and circuit board workability.

The present invention employs the following means in order to solve such problems. That is,
(1) On at least one surface of a biaxially oriented film (A layer) made of a resin composition containing poly-p-phenylene sulfide as a main component, at least one copolymer unit other than p-phenylene sulfide units. And a layer (B layer) made of copolymerized polyphenylene sulfide containing and satisfying the following formulas 1 and 2 and a polymer resin layer (C layer) having substantially no melting point are laminated in this order. There is a laminated film.
50 ≦ PPSF (B) ≦ 95 Formula 1
3 ≦ COPF (B) <50 Formula 2
PPSF (B): the content of the p-phenylene sulfide unit in the B layer expressed in mol% with respect to all the repeating units COPF (B): the amount of copolymer units contained next to the p-phenylene sulfide unit in the B layer Content represented by mol% with respect to all repeating units (2) The laminated film according to (1), wherein the C layer is a layer made of an aromatic polymer having substantially no melting point. .
(3) A printed wiring board in which an electric circuit is formed on at least one surface of the surface of the C layer of the laminated film described in (1) or (2).

  Since the present invention is configured as described above, the heat resistance and thermal dimensional stability at the time of solder processing, which have been the conventional problems, are maintained while maintaining the excellent high-frequency characteristics, low moisture absorption, flame retardancy, and mechanical characteristics of the PPS film. Thus, a laminated film having adhesion and circuit processability was obtained. Needless to say, the laminated film can be applied to various circuit boards typified by flexible printed wiring boards, and is particularly suitable for high-frequency compatible circuit boards.

  The laminated film of the present invention comprises at least one surface of a biaxially oriented film (A layer) made of a resin composition containing poly-p-phenylene sulfide (hereinafter sometimes abbreviated as “p-PPS”) as a main component. And a layer (B layer) comprising a copolymerized polyphenylene sulfide (hereinafter sometimes abbreviated as “copolymerized PPS”) containing at least one copolymer unit other than the p-phenylene sulfide unit. The basic structure is that polymer resin layers (C layer) not having a layer are laminated in this order.

  In the present invention, p-PPS refers to a polymer composed of structural units represented by the following formula containing 90 mol% or more, more preferably 95 mol% or more of p-phenylene sulfide units.

  When the PPS component is 90 mol% or more, the crystallinity and thermal transition temperature of the polymer, the melting point, etc. are high, and the heat resistance, dimensional stability, mechanical properties, which are the characteristics of the resin composition containing PPS as the main component, This is because the chemical resistance and flame retardancy can be fully exhibited. The polymer may contain other copolymerizable units containing sulfide bonds. In this case, the structural unit may be either a random type or a block type copolymerization method.

In the present invention, the resin composition containing p-PPS as a main component refers to a composition containing 60% by mass or more of p-PPS. When the content of p-PPS is 60% by mass or more, the mechanical properties, heat resistance, chemical resistance, hydrolysis resistance, flame resistance, etc. of the layer made of the composition of the laminated film of the present invention are sufficient. Can be demonstrated. Further, the remaining less than 40% by mass in the composition may contain additives such as polymers other than PPS, inorganic or organic fillers, lubricants, and colorants. Furthermore, the melt viscosity of the composition is preferably 100 to 50,000 poises, more preferably 500 to 20000 poises at a temperature of 300 ° C. and a shear rate of 200 sec ⁻¹ . This range is selected because it is easy to form and form a film and has good laminating workability.

  The biaxially oriented film made of a p-PPS resin composition is a film (hereinafter abbreviated as PPS film) obtained by melt-extruding, biaxially stretching, and heat-treating the resin composition containing p-PPS as a main component. In view of stackability, the thickness is preferably in the range of 4 to 300 μm.

The copolymerized PPS of the present invention refers to a polymer constituted by copolymerizing at least one other copolymer unit with a p-phenylene sulfide unit as a main repeating unit, and p-phenylene sulfide units. Next, the content of the copolymer unit that is contained in the second most is a polymer that satisfies the following formula.
50 ≦ PPSF (B) ≦ 95 Formula 1
3 ≦ COPP (B) ≦ 50 Formula 2
Here, PPSF (B) means content (mol%) with respect to all the repeating units of the p-phenylene sulfide unit in B layer of the laminated | multilayer film of this invention. COPP (B) refers to the content (mol%) of copolymerized units contained in the B layer of the laminated film of the present invention after the p-phenylene sulfide with respect to all repeating units.

The content of the p-phenylene sulfide unit in the copolymerized PPS of the B layer is preferably 50 mol% or more and 95 mol% or less from the viewpoint of heat resistance, thermal dimensional stability, adhesion and the like of the laminated film. More preferably, it is 70 mol% or more and 92 mol% or less. That is, if the content is less than the above lower limit value, the heat resistance (including solder heat resistance) and thermal dimensional stability of the laminated film tend to be lowered, and the workability of the circuit board may be adversely affected. . On the other hand, when the content exceeds the upper limit, the adhesive strength with the C layer is reduced. Examples of the copolymer unit include the following m-phenylene sulfide units (wherein X represents an alkylene, CO, or SO ₃ unit, and R represents an alkyl, nitro, phenylene, or alkoxy group). A plurality of these units may exist.

  Among these, particularly preferred copolymer units are m-phenylene sulfide units, which are excellent in heat resistance, thermal dimensional stability and adhesion, and workability of the laminated film is also good. The amount of copolymerization of these units is 3 mol% or more and less than 50 mol% (more preferably 5 mol) with respect to the total number of repeating units after the p-phenylene sulfide unit which is the main repeating unit of the copolymerized PPS. % Or more and less than 30 mol%) is preferable for improving heat resistance, thermal dimensional safety, adhesion, workability of laminated film, and the like. The remaining part of the repeating unit other than the copolymerized PPS may be composed of other copolymerizable units, but the trifunctional phenylene sulfide unit represented by the following formula is 1 mol% or less of the entire copolymer. Is preferable from the viewpoint of not deteriorating heat resistance, dimensional stability, adhesion, and workability. Further, the form of copolymer may be random or block, but is preferably random.

The melting point of the copolymerized PPS resin layer of the present invention is preferably in the range of 200 ° C to 285 ° C. The melt viscosity is 300 ° C., a shear rate of 200 sec ⁻¹ , 50 to 20000 poise (more preferably 100 to 10000 poise), and further substantially non-oriented improves the adhesion to the C layer. preferable. Moreover, the layer which consists of copolymer PPS of this invention means the resin layer which this copolymer PPS composition contains 60 mass% or more. This is for imparting heat resistance and adhesion. If the remaining amount is less than 40% by mass, another polymer, lubricant, antistatic agent, colorant and the like may be contained.

  Next, the polymer resin layer having substantially no melting point of the C layer in the laminated film of the present invention has a decomposition point of the polymer as the main component lower than its theoretical melting point (or glass transition point). After confirming the melting point (or glass transition point) peak by heating using a differential calorimetric method (DSC method) on the polymer (1st run), immediately cooled immediately and heated again (2nd run) It refers to a polymer resin in which the melting point (or glass transition point) peak appearing in the 1st run cannot be confirmed. In this case, the peak appearing in the 1st run is taken as the decomposition point of the polymer. In the present invention, those having a decomposition point of 300 ° C. or higher are preferable in terms of improving solder heat resistance and thermal dimensional stability of the laminated film. A particularly preferred polymer is an aromatic polymer. Examples of the polymer include polyimide, polyamideimide, aromatic polyamide, aromatic polyesterimide, aromatic polyamideimidazole, and aromatic polyamide hydraside. Further, the C layer preferably has heat resistance.

  In the laminated film of the present invention, the biaxially oriented PPS film layer (A layer) and the copolymer PPS layer (B layer) and the polymer resin layer (C layer) having substantially no melting point are provided on at least one side of the A layer. What is laminated in this order is the basic configuration. A preferable configuration that can achieve the most efficient provision of solder heat resistance and thermal dimensional stability, which is the object of the present invention, is a double-sided laminated film in which a B layer and a C layer are laminated in this order on both sides of the A layer. . In addition, it is preferable not to use a resin other than the resin constituting each layer referred to in the present invention between the respective layers because the excellent dielectric characteristics and moisture absorption characteristics of PPS can be maintained, but it is used as long as the above effects of the present invention are not impaired. May be. Further, the thickness of the entire laminated film is preferably in the range of 5 to 350 μm (more preferably 6 to 300 μm), and the object of the present invention can be easily achieved efficiently, and is also preferable from the viewpoint of the workability of the laminated film and circuit board.

The ratio of the thickness of the B layer to the A layer (total B thickness / total A thickness) is preferably in the range of 0.02 to 0.5 in terms of heat resistance, thermal dimensional stability, and adhesion. Further, the content of the copolymerized phenylene sulfide unit in the p-PPS composition of the A layer expressed in mol% with respect to all repeating units: COPP (A) and the copolymerized phenylene sulfide unit in the copolymerized PPS composition of the B layer The relationship of the content expressed by mol% with respect to all repeating units: COPP (B) is preferably in the range of Formula 3 because it is advantageous for heat resistance and workability.
COPP (B)> COPP (A) Equation 3
The relationship between the thickness of the C layer, the thickness of the A layer, and the thickness of the B layer (total C thickness / total A thickness + total B thickness) is in the range of 0.02 to 0.5 in terms of solder heat resistance. It is preferable in terms of thermal dimensional stability and prevention of cracking of the C layer during bending. In the laminated film of the present invention, a structure in which the B layer and the C layer are laminated on both sides of the A layer is particularly preferable from the viewpoints of solder heat resistance, thermal dimensional stability, curling of the laminated film, workability of the circuit board, and the like. In this case, the difference in thickness between the B layer and the C layer on both sides with the A layer as the center layer is preferably within ± 10% from the viewpoint of curling during heating, workability of the circuit board, and the like. Further, another film, sheet, fiber, paper, metal or the like may be laminated on the surface of the laminated film of the present invention, or printing or vapor deposition may be performed.

  Further, the printed wiring board of the present invention is one in which an electric circuit is formed on at least one surface of the above laminated film via a C layer. In view of improvement of solder heat resistance and circuit processability, which are the objects of the present invention, a configuration in which an electric circuit is laminated on at least one side of a double-sided laminated film of C layer / B layer / A layer / B layer / C layer is preferable. Here, the electric circuit refers to an electric path formed by a conductor such as metal or conductive paint. The thickness of the conductor layer is not particularly limited, but is generally about 0.1 to 40 μm.

  In addition, the thickness of the laminated film used in the present invention is preferably in the range of 6 to 300 μm from the viewpoint of development application and workability. The electric circuit may or may not be provided with various adhesives. Two or more printed wiring boards may be laminated, or may be bonded to a rigid circuit board. The shape and size are not limited.

Next, the manufacturing method of the laminated film of this invention is described.
First, a laminated film (A / B or B / A / B, hereinafter referred to as an intermediate laminated film) of a PPS film layer composed mainly of an A-layer p-PPS layer and a B-copolymerized PPS layer, which is an intermediate of the laminated film of the present invention. The manufacturing method of (sometimes abbreviated as “film”) will be described. The copolymerized PPS layer of the present invention needs to satisfy the following formulas 1 and 2, but the relationship between the A layer and the B layer of the intermediate laminated film is that the following formulas 1 to 4 should be satisfied. This is preferable because the solder heat resistance, thermal dimensional stability and adhesion can be improved efficiently.
50 ≦ PPSF (B) ≦ 95 Formula 1
3 ≦ COPP (B) ≦ 50 Formula 2
COPP (B)> COPP (A) Equation 3
PPSF (A) ≧ 90 Equation 4
PPSF (A): Content (mol%) of p-phenylene sulfide units in the PPS-BO of the A layer with respect to all repeating units.
COPP (A): Content (mol%) of copolymerized units contained in the layer A after the p-phenylene sulfide units in the amount of all repeating units.
PPSF (B): Content (mol%) of the p-phenylene sulfide unit in the copolymer PPS layer of the B layer with respect to all repeating units.
COPP (B): Content (mol%) of copolymerized units contained in the B layer after the p-phenylene sulfide units in the second layer with respect to all repeating units.

There are various polymerization methods for copolymerizing PPS of the B layer of the present invention. Alkali sulfide, p-dihalobenzene (main component monomer) and subcomponent monomer are blended so as to satisfy the above formulas 1 and 2, and a polar solvent is used. Among them, a method of polymerizing at a high temperature and high pressure in the presence of a polymerization aid is preferable because the degree of polymerization of the resulting polymer is likely to increase. In particular, it is most preferable to use sodium sulfide as the alkali sulfide, p-dichlorobenzene as the main component monomer, and N-methylpyridone as the solvent. A secondary component monomer is allowed to coexist with p-dichlorobenzene (main component monomer). Examples of the subcomponent monomer include those having the following chemical formula (where X represents an alkylene, CO, or SO3 unit, and R represents an alkyl, nitro, phenyl, or alkoxy group). There may be a monomer. A preferred accessory component monomer is (Chemical Formula 12).

The p-PPS of the A layer of the present invention is polymerized in the same manner as the copolymerized PPS described above, but does not contain a subcomponent monomer or reduces the amount so as to satisfy the above formulas 3 and 4.
Of course, you may mix | blend the trifunctional monomer represented by the following Formula in the case of superposition | polymerization in order to adjust the melt viscosity of copolymerization PPS and p-PPS.

  Additives such as inorganic or organic fillers are added to the copolymerized PPS and p-PPS thus obtained as necessary to obtain resin compositions. The resin composition is blended and mixed with a PPS polymer obtained in powder using a mixer or the like, or further supplied to a melt extruder represented by an extruder, melt kneaded, melt extruded into a gut shape, and cooled. In addition, a method of obtaining pellets by cutting to an appropriate length is preferable.

  Coating, laminating, co-extrusion methods, etc. are used as the method for obtaining the intermediate laminated film, but it is co-extruded and biaxially stretched, or p-PPS is melt-extruded, cooled (cast) or uniaxially stretched into another melt. A method in which the copolymerized PPS is extruded and laminated from an extruder and then stretched and heat-treated is preferable because control of the thickness of each layer, adhesion between layers, orientation control of the B layer and the like are easy. Particularly preferred are coextrusion and biaxial stretching. In the co-extrusion method, two or more melt-extrusion apparatuses are prepared and merged and laminated in the polymer flow path between the melt-extrusion apparatus and the die, but preferably merged and laminated upstream (for example, a manifold) from the die. That is, p-PPS and copolymerized PPS that are supplied to separate melt-extrusion apparatuses and heated and melted above the melting point of each composition are two layers in a molten state in a merging apparatus provided between the extrusion apparatus and the die. Or it is laminated | stacked on 3 layers and extruded from a slit-shaped base lip. The molten laminated sheet is continuously cooled on a rotating cooling drum to a temperature not higher than the glass transition point of the copolymerized PPS resin composition to obtain a substantially amorphous laminated sheet. Although a well-known apparatus can be applied to the melt extrusion apparatus, an extruder is simple and preferable. The merging device has a function capable of being laminated in a molten state in two layers (A / B) or three layers (B / A / B) depending on the configuration of the laminated film.

  Next, this amorphous laminated sheet is subjected to biaxial stretching and heat treatment. As the biaxial stretching method, known methods such as sequential biaxial stretching method, simultaneous biaxial stretching method, and tubular method are used. In particular, a sequential biaxial stretching method by roll stretching and oven stretching called a tenter or a simultaneous biaxial stretching method by a tenter method is preferable because it is easy to control the balance of mechanical properties, thermal dimensional stability, and the like. The stretching conditions are preferably in the range of a stretching ratio of 2.0 to 5.0 times at a temperature of 80 to 120 ° C. in both the longitudinal direction and the width direction of the film. Furthermore, heat treatment is performed in a heat treatment zone provided in the same tenter for several seconds to several minutes in the range of 200 ° C. to p-PPS melting point, but the temperature is higher than the melting point of the copolymerized PPS layer used and lower than the melting point of p-PPS. In view of thermal dimensional stability, it is preferable to set the temperature as high as possible. Furthermore, limiting shrinkage (relaxation) in the range of 0 to 20% is preferable because thermal dimensional stability is improved. Furthermore, for the purpose of improving thermal dimensional stability, free relaxation may be performed at an appropriate temperature above the glass transition point.

  Next, the method of laminating the C layer of the polymer resin layer having substantially no melting point on the surface of the B layer of the intermediate laminated film obtained above includes methods such as coating and laminating, but the thickness of the C layer The coating (coating) method is preferred because it is easy to control and is simple. The method comprises applying the resin composition solution of the C layer on the B layer of the intermediate laminated film obtained above by various methods such as gravure method, reverse coater method, die coating method, comma coating method, dipping method, A method may be used in which the solvent is removed by drying, or the C layer resin is applied to another substrate having releasability by the same method and then laminated on the B layer surface of the intermediate laminated film by transfer. Furthermore, in the film forming process for producing the intermediate laminated film, a method of applying before or during the stretching process and drying in the heat treatment process in the tenter is also used. Here, the B-layer resin composition is preferable because the aromatic polymer is highly effective in improving the solder heat resistance and thermal dimensional stability, which are the objects of the present invention. Each of the polymers can be produced using a known method. For example, the polyimide that easily achieves the object of the present invention includes tetracarboxylic acid such as pyromellitic acid, 1,2,3,4-benzenetetracarboxylic acid and / or acid anhydride thereof, benzidine, diaminodiphenolmethane, and the like. Obtained by dehydrating condensation with one or more compounds selected from the group consisting of aliphatic primary diamines and / or aromatic primary diamines, specifically, obtaining polyamic acid, and then heating and / or Or the method of carrying out dehydration ring closure using a chemical ring-closing agent can be illustrated. The conditions necessary for ring closure in this case differ depending on the type of polymer, the type and amount of the catalyst, but the temperature range of 150 to 230 ° C. and the range of 0.2 to 20 minutes are the stability and continuous processability of the C layer and the film. It is preferable from the viewpoint of preventing thermal deterioration and the like. In the ring-closing reaction, a so-called polyimide resin reacted in advance may be used as it is, or the film surface may be subjected to a ring-closing reaction by heating after coating processing. The aromatic polyamide can be obtained by, for example, condensing isophthalic acid chloride and metaphenylenediamine in a polar solvent to obtain polymetaphenylene isophthalamide. Moreover, the coating agent marketed can also be used from simplicity.

  Next, the printed wiring board is manufactured from the laminated film of the present invention obtained above, after the metal foil is laminated on the C layer side of the laminated film of the present invention via an adhesive, Etch the circuit pattern with ferric chloride aqueous solution, etc., or provide a conductive layer such as metal layer on the C layer surface of the laminated film by metal deposition or sputtering method, and form the desired circuit pattern by the above chemical etching method There is a way to do it. The thickness of the conductive layer in this case varies depending on the use of the printed wiring board, but generally a range of 0.1 to 40 μm is used. The conductor used is a simple substance of metal such as copper, aluminum, iron, SUS, or two or more kinds of compounds and alloys. Moreover, as for the adhesive when laminating metal foil via an adhesive, a heat-resistant adhesive such as epoxy, acrylic, silicon, or urethane is generally used, and the thickness is 10 to 30 μm after drying. This range is optimal for the balance between adhesion and solder heat resistance. As a method for applying the adhesive, known methods such as a gravure roll coater method, a reverse roll coater method, and a die coater method are used. The lamination with the metal layer is generally a hot press roll method or a hot plate press method. Further, the adhesive may be cured by heat or other energy. The hot press lamination is usually performed at a temperature of 80 to 150 ° C. and a press pressure of 1 to 5 kg / cm. The curing is generally performed at 50 to 150 ° C. for 1 to 60 hours. Moreover, the pattern of an electric circuit can also be formed by methods, such as silk printing, on the C layer surface of the laminated | multilayer film of this invention for the paint which has electroconductivity like carbon and a silver paste. The electric circuit of the present invention may be double-sided or single-sided, or the same or different types of circuit boards may be laminated in two or more layers. Also, it may be combined with other rigid boards, or other materials such as metal plates, fiber sheets, paper, cloth, other types of plastic sheets and films may be laminated on one or both sides of the printed wiring board of the present invention. Good.

The following examples illustrate the present invention in more detail.
<Physical properties and evaluation methods, evaluation criteria>
(1) Lamination structure, lamination thickness ratio The cross section of the lamination film was obtained by taking an electron micrograph under the following conditions, measuring the thicknesses of the A layer, the B layer and the C layer with a metal rule and calculating the lamination ratio.
Measuring device: S-4300 type field emission scanning electron microscope manufactured by Hitachi, Ltd. Measurement conditions: Accelerating voltage 3 kV
Magnification: 500 to 1000 times depending on the thickness of the laminated film.

(2) Melting point, glass transition point, decomposition point of laminated film C layer The C layer (surface layer) of the laminated film is scraped and heated up under the following conditions by differential calorimetry (DSC method), and the melting point or glass transition point. A peak was confirmed (1st run). Thereafter, it was rapidly cooled, and the temperature was raised again under the same conditions, and a melting point or a glass transition point peak was confirmed (2nd run). Here, when the same peak that appeared in the 1st run also appeared in the 2nd run, the melting point or glass transition point of the resin was taken. On the other hand, when the peak that appeared in the 1st run did not appear in the 2nd run, the peak that appeared in the 1st run was taken as the decomposition point.
Here, those having a melting point or glass transition point were indicated as having a melting point, and those having a decomposition point were indicated as having no melting point.
Measuring device: DSC7 manufactured by PERKIN ELMER
Assumed conditions: Temperature rising rate 20 ° C./min Sample amount 10 mg.

(3) Solder heat resistance A
Visually observe the state of thermal deformation of the sample when a 2 cm square sample is floated for 10 seconds with the solder in the solder bath set at 260 ° C. (± 5 ° C.) so that the C layer surface is in contact with the solder surface. Judged. That is, the solder heat resistance A is an evaluation for determining thermal deformation due to softening during solder processing and thermal deformation due to thermal dimensional change, and is an evaluation of the solder heat resistance of the entire laminated film.
○: Almost no thermal deformation.
Δ: Slight deformation such as curling but no problem in practical use.
×: Level of heat wrinkles and curls that cannot be used practically.

(4) Solder heat resistance B
An electrolytic copper foil having a thickness of 36 μm (Fukuda Metal Foil Powder Co., Ltd .: UH type) was laminated on the C layer surface of the laminated film of the present invention via the following epoxy adhesive. The thickness of the adhesive was 18 μm (after drying), and a reverse roll coater was used for coating. The lamination was performed by a heated roll press system at a temperature of 100 ° C., a pressure of 3 kg / cm, and the thermosetting conditions were 80 ° C. for 48 hours and then 100 ° C. for 5 hours. When a part of the laminated film thus obtained is peeled off between the copper foil and the film, the peeling interface is held with two tweezers and peeled while being immersed in the solder bath of the above condition (2) The heat resistance of the following B layer was determined from peelability. That is, the solder heat resistance B evaluates the degree of softening due to heat at the time of soldering the B layer.
(Epoxy adhesive used)
60% by mass of a polyamide resin (Henkel's Versalon 1105), 30% by mass of a bisphenol A epoxy resin (Epicoat 834 manufactured by Shell), 8% by mass of a dimer acid glycidyl ester modified product (Epicoat 872 manufactured by Shell), imidazole 2 Mass% was mixed and dissolved in dimethylformamide to obtain an adhesive solution of 40 mass% and 2 poise.
(Judgment)
○: The B layer portion is not easily peeled off (the C layer and the adhesive layer are peeled off).
Δ: Peeled at the B layer portion, but requires some peeling force.
X: The B layer portion was softened and easily peeled off.

(5) Adhesiveness 100 pieces of 1 mm ² crosscuts (cutting only the C layer) are put in the C layer of the laminated film, cellophane adhesive tape (manufactured by Nichiban: CT18) is pasted on this part, and a weight of 19 is applied using a rubber roller. The sheet was reciprocated 3 times at 6 N and then pressed, peeled in the direction of 90 degrees, and the number of cross-cut portions where the resin remained was evaluated and judged according to the following criteria.
○: 80% or more Δ: 50% or more and less than 80% ×: less than 50%

(6) Sled Adhesive is applied to one side of the laminated film by the method of (4) above, and 36 μm electrolytic copper foil (made by Fukuda Metal Foil Powder Industry: UH type) at 100 ° C. and 3 kg / cm (tension-free) ), And the adhesive layer was thermally cured at a temperature of 80 ° C. for 24 hours and then at 100 ° C. for 5 hours under a pressure of 0.6 kg / m ² . This sample was cut into a 5 cm square, one end was fixed to a glass plate, and the height of the most warped was taken as the warp height and evaluated according to the following criteria. The warp height was measured with a metal scale.
○: Less than 15 mm Δ: 15 mm or more and less than 30 mm x: 30 mm or more.

(7) Frequency characteristics of dielectric loss Measure dielectric loss at a frequency of 1KHz (normal frequency) and 1MHz (high frequency) in accordance with JIS C2151 (1990) and calculate the frequency change rate (1MHz / 1KHz). Judged by. The measuring instrument was PRECISION LCR METER (4284A (20 Hz to 1 MHz) manufactured by Hewlett-Packard Co.), and the dielectric measurement electrode was HP 16451B manufactured by Yokogawa Hewlett-Packard.
○: Less than 5 Δ: 5 or more and less than 10 ×: 10 or more.

(8) Mechanical properties (breaking strength, breaking elongation)
Using a Tensilon-type tensile tester (TENSION VTM-III manufactured by Toyo Baldwin), the strength at break when a sample with a film width of 10 mm and a test length of 50 mm was measured at a pulling speed of 200 mm / min was determined as the breaking strength (kg / mm ² ). The elongation at break was expressed as the elongation at break (%), and the longitudinal direction of the film was measured.

(9) Flame retardancy The laminated film was cut into a 50 mm × 200 mm strip and rolled into a cylinder with a diameter of 12.7 mm and a length of 200 mm. One end of the cylindrical sample in the longitudinal direction was fixed, and a flame of about 20 mm was exposed to the other end in the vertical direction for 3 seconds, followed by flame removal. At this time, the burning time of the sample after flame separation was measured with a stopwatch. This test was performed twice on the same sample, and the flame retardancy was evaluated by the total burning time.

(10) Moisture absorption rate After the sample is vacuum dried (100 ° C., 5 mmHg or less, 24 hours), the mass (W1) of the sample is measured with a direct balance. Thereafter, the sample was aged in a constant temperature and humidity chamber of 40- ° C. and 75% RH for 24 hours, and the mass (W2) of the sample was measured with a direct balance, and the value of W2−W1 / W1 × 100 (%) was defined as the moisture absorption rate. .

(11) Solder heat resistance of printed wiring board (4) Copper width 1 mm, etching interval 5 mm on the copper foil layer of the copper-coated product obtained by the same method as the copper-laminated laminated film prepared in the evaluation of (4) solder heat resistance B A printed wiring board was prepared by etching a copper foil with a 12% aqueous solution of ferric chloride in a grid pattern. The substrate was cut into a size of 2 mm × 3 cm, the printed wiring surface was floated on the solder surface at 260 ° C. for 10 seconds, and the solder heat resistance of the printed wiring substrate was determined by the change in the appearance of the film in and after the soldering.
○: Almost no thermal deformation.
Δ: Slightly curled and deformed to the extent that there is no problem in practical use, although there is a deformation of the inter-circuit portion.
X: Deformation that cannot be used practically due to severe shrinkage between heat wrinkles, curls, and circuits.

(12) Adhesiveness of the printed wiring board The copper foil part of the printed wiring board prepared in the above (11) is peeled off in a 90 degree direction with Tensilon (VTM-III manufactured by Toyo Baldwin) (peeling speed: 50 mm / min) The force was determined and the adhesion was determined according to the following criteria.
○: 800 g / cm or more (a level where there is no problem even in a high-density circuit)
(Triangle | delta): Less than 800 g / cm 500 g / cm or more (a level which does not have a problem with a normal circuit)
X: Less than 500 g / cm (a level that causes a practical problem).

Example 1
(1) Production of copolymer PPS resin composition An autoclave was charged with 100 moles of sodium sulfide nonahydrate, 45 moles of sodium acetate and 25 liters of N-methyl-2-pyrrolidone (hereinafter sometimes referred to as NMP). While expanding, the temperature was gradually raised to 220 ° C. and the contained water was removed by distillation.
89 mol of p-dichlorobenzene as a main component monomer, 10 mol% of m-dichlorobenzene as a secondary component monomer, and 0.2 mol% of 1,2,4-trichlorobenzene were added to the system after dehydration. The mixture was added together with 5 liters of NMP, and nitrogen was pressurized to 3 kg / cm ² at 170 ° C., followed by heating and polymerization at 260 ° C. for 4 hours. After completion of the polymerization, the mixture was cooled, the polymer was precipitated in distilled water, and a small block polymer was collected with a wire mesh having a 150 mesh opening.
The polymer was washed 5 times with distilled water at 90 ° C. and then dried at 120 ° C. under reduced pressure to obtain a white granular copolymer PPS having a melt viscosity of 1000 poise and a melting point of 263 ° C. Further, 0.5% by mass of spherical silica having an average particle diameter of 0.5 μm was blended with this polymer and uniformly mixed with a blender, and then extruded in a gut shape at a temperature of 320 ° C. with a 30 mm pore diameter twin screw extruder, 5 mm It was cut to a long length and pelletized.
(2) Production of p-PPS resin composition Production of copolymerized PPS resin composition of (1) above, except that 101 mol% of p-dichlorobenzene is used as the main component monomer and no accessory component monomer is used. In the same manner as above, a p-PPS resin composition was obtained. The p-PPS resin composition had a melt viscosity of 3000 poise and a melting point of 285 ° C.
(3) Production of intermediate laminated film The copolymerized PPS resin composition and p-PPS resin composition obtained in (1) and (2) above were each dried under reduced pressure (vacuum degree 5 mmHg) at a temperature of 180 ° C. for 4 hours. . This resin composition is supplied to separate extruders, melted (both polymers are extruded at 320 ° C.), laminated in two layers with a double tube type laminating device at the top of the die, and discharged from a T-die die. Then, it was quenched with a cooling drum for cooling to obtain a two-layer sheet (thickness: 620 μm) of a substantially amorphous copolymerized PPS resin composition / p-PPS resin composition.
Subsequently, it was made into the biaxially stretched film with the sequential biaxial stretching apparatus. That is, the unstretched two-layer laminated sheet obtained above was supplied to a longitudinal stretching apparatus consisting of a roll group and stretched in the longitudinal direction, and then stretched in the width direction using a tenter. The stretching conditions were a temperature of 100 ° C. for both axes and a stretching ratio of 3.5 times. Further, heat treatment was performed at a temperature of 270 ° C. for 10 seconds in a heat treatment zone in the tenter. Furthermore, 5% relaxation was performed in the width direction for the purpose of improving the thermal dimensional stability. Furthermore, the film was passed through a heating oven provided with a group of rolls and relaxed freely at a temperature of 200 ° C. The total thickness of the two-layered intermediate laminated film thus obtained was 25 μm, and the thickness of the copolymerized PPS resin composition layer was 1.5 μm. The surface of the copolymerized PPS resin composition layer of the two-layer intermediate laminated film was subjected to corona discharge treatment at a treatment strength of 6000 J / m ² .
(4) Manufacture of laminated film Colloidal silica after diluting “Torenice” # 3000 manufactured by Toray Industries, Inc. as a polyimide (hereinafter sometimes abbreviated as PI) solution with NMP to a solid content concentration of 10% by mass. NMP dispersion (“OSCAL” 5116, manufactured by Catalyst Kasei Kogyo Co., Ltd., solid content concentration 10% by mass, primary particle size 80 nm) was prepared and adjusted so that polyimide / silica = 60/40.
Using this solution, a gravure roll coater method was applied to the surface of the copolymer PPS resin composition layer of the previously obtained two-layer intermediate laminated film, dried at 130 ° C., and then heat-treated at 200 ° C. The thickness of the polyimide layer (C layer) of the obtained laminated film was adjusted to 2.0 μm. The obtained laminated film is designated as laminated film-1.

Example 2
(1) Production of PPS resin composition In the same manner as in Example 1, 50.8 mol% of p-dichlorobenzene as the main component monomer, 49 mol% of m-dichlorobenzene as the subcomponent monomer, and 0 A copolymerized PPS resin composition prepared with 2 mol% of 1,2,4-trichlorobenzene was prepared.
The polymer used in Example 1 was used for the p-PPS resin composition.
(2) Production of intermediate laminated film Using the melt laminating apparatus capable of laminating three layers by the method of Example 1, a substantially amorphous copolymerized PPS resin composition layer / p-PPS resin composition layer / copolymer A three-layer laminated sheet of polymerized PPS resin composition layers was obtained. The laminated sheet was sequentially biaxially stretched, heat-treated and relaxed by the method of Example 1. The thickness of the obtained three-layer intermediate laminated film was 25 μm, and the copolymer PPS resin layer was 1.5 μm on one side. Further, a corona discharge treatment was performed on both surfaces of the three-layer intermediate laminated film with a treatment strength of 6000 J / m ² .
(3) Manufacture of laminated film By the method of Example 1, PI resin layers were provided on both surfaces of the three-layer intermediate laminated film. The coating thickness was adjusted to 2 μm after drying and heat treatment on both sides. The laminated film thus obtained is designated as laminated film-2.

Example 3
(1) Production of Intermediate Laminated Film The copolymerized PPS resin composition was prepared by the method of Example 1, with 69.8 mol% of p-dichlorobenzene as the main component monomer and 30 mol% of m-dichloro as the accessory component monomer. Polymerization was carried out under the conditions of Examples using benzene and 0.2 mol% of 1,2,4-trichlorobenzene. Other conditions are the same as in the first embodiment. Further, the p-PPS resin layer used in Example 1 was used. Using this copolymerized PPS resin composition and p-PPS resin composition, the method of Example 2 was used, and a three-layer intermediate having the same configuration and a thickness of 25 μm (the thickness of the copolymerized PPS resin layer was 1.5 μm per side) A laminated film was obtained. Corona discharge treatment was performed on both sides of the obtained intermediate laminated film at a treatment strength of 6000 J / m ² .
(2) Manufacture of laminated film By the method of Example 1, PI resin layers were provided on both surfaces of the three-layer intermediate laminated film. The coating thickness was adjusted to 2 μm after drying and heat treatment on both sides. The laminated film thus obtained is designated as laminated film-3.

Example 4
Using the copolymerized PPS resin composition and the p-PPS resin composition of Example 1, the copolymer PPS resin composition layer / p-PPS resin composition layer / copolymerized PPS resin composition layer by the method of Example 2 A three-layer intermediate laminated film having a thickness of 25 μm (copolymerized PPS resin layer thickness of 1.5 μm per side) was obtained. Corona discharge treatment was performed on both surfaces of this intermediate laminated film at a treatment strength of 6000 J / m ² , and a laminated film-4 having a PI layer of 2 μm provided on both sides in the same manner as in Example 1 was obtained.

Example 5
The copolymerized PPS resin composition was prepared according to the method of Example 1, with 96.8 mol% p-dichlorobenzene as the main component monomer, 3.0 mol% m-dichlorobenzene as the accessory component monomer, and 0.2. It was obtained by polymerization under the conditions of Example 1 using 1 mol% 1,2,4-trichlorobenzene. The p-PPS resin composition produced in Example 1 was used.
The method of Example 2 was used to produce a three-layer intermediate laminated film and a laminated film. The obtained laminated film was designated as laminated film-5.

Example 6
(1) Production of PPS Laminated Film The three-layer intermediate laminated film obtained in Example 4 was used (6000 J / m ² of corona discharge treatment was applied to both sides).
(2) Production of laminated film Polyamideimide solution ("H1-400" manufactured by Hitachi Chemical Co., Ltd., solid content concentration: 30% by mass, viscosity: 60 poise) was used for the C layer resin. The solution was diluted with a solvent having a mass ratio of NMP / dimethylformamide / toluene / methylene chloride = 40/20/30/10 to be 10% by mass, and an NMP dispersion of colloidal silica (manufactured by Catalyst Chemical Industries, Ltd.) “OSCAL” 5116, solid content concentration 10% by mass, primary particle size 80 nm) were prepared and adjusted so that polyamideimide / silica = 60/40. This solution was applied to both sides of the three-layer intermediate laminated film of Example 4 by the method of Example 1. The coating material was dried under the conditions of 110 ° C, 130 ° C, 200 ° C and 110 ° C. The time was 20 seconds for each zone. The coating thickness was adjusted to 2 μm per side after drying. Let the obtained laminated film be laminated film-6.

Comparative Example 1
The single p-PPS resin composition obtained in Example 1 was melt-extruded, sequentially biaxially stretched and heat-treated under the methods and conditions of Example 1 to obtain a biaxially stretched film of p-PPS resin composition having a thickness of 25 μm. It was. Let it be PPS film-1.

Comparative Example 2
For comparison, a three-layer intermediate laminated film of Example 4 (hereinafter referred to as intermediate laminated film-1) was prepared.

Comparative Example 3
Both surfaces of the PPS film-1 obtained in Comparative Example 1 were subjected to plasma treatment in argon gas (applied voltage 0.6 kV, speed 0.25 m / min), and the PI solution used in Example 1 was used as in Example 1. The method was applied. The coating thickness was adjusted to 2 μm after drying and heat treatment. Let the obtained laminated | multilayer film be laminated | multilayer film-7.

Comparative Example 4
(1) Production of PPS Laminated Film A three-layer intermediate laminated film having a total thickness of 50 μm (copolymerized PPS layer thickness of 3 μm per side) was produced in the same manner as in Example 4.
(2) Manufacture of laminated film AURUM450: Mitsui Chemicals pellets were prepared as a thermoplastic PI resin. The resin was melt-extruded at a temperature of 320 ° C. with a 30 mm pore size melt extruder, and was stretched about 2.5 times when it was press-cast to a cooling drum. The resulting film was 4-5 μm thick. This film was thermocompression-bonded on both surfaces of the three-layer intermediate laminated film obtained in (1) above by a hot roll press method to obtain a laminated film-8. The lamination thickness was about twice that of the laminated films of Examples 1 to 6 and Comparative Example 3, but the lamination ratio was adjusted to be about the same. The heating press temperature was 250 ° C. and the press pressure was 5 kg / cm. When PI of the surface layer C layer of this laminated film-8 was subjected to DSC analysis, an endothermic peak considered to be a glass transition temperature was observed at 253 ° C. The decomposition point was a little over 400 ° C.

Comparative Example 5
For comparison, a polyimide film (PI-1) of 25 μm (Toray-DuPont Kapton 100H) was prepared.

Example 7 to Example 12
The laminated films-1 to 6 of Example 1 to Example 6 were processed by the following method to prepare six types of printed wiring boards shown in Table 1. The obtained printed wiring boards were designated as wiring boards -1 to 6, respectively.

(1) Preparation of Adhesive As an adhesive, 60% by mass of a polyamide resin (Henkel's Versalon 1105), 30% by mass of a bisphenol A-based epoxy resin (Epicoat 834 manufactured by Shell), a dimer acid-based glycidyl ester modified product (shell) Epicoat 872) 8% by mass and 2% by mass of imidazole were mixed and dissolved in dimethylformamide, and an adhesive solution having a solid content concentration of 40% by mass and 2 poise was used.

(2) Manufacture of copper-clad laminated film The adhesive of (1) above was applied to the C surface of laminated films 1 to 6 using a reverse coater. The coating thickness was adjusted to 18 μm after the solvent was dried. The drying temperature was performed in two zones of 100 ° C. and 120 ° C. The coating speed was 10 m / min. A 36 μm-thick electrolytic copper foil (manufactured by Fukuda Metal Foil Powder Co., Ltd .: UH type) was thermocompression-bonded to this adhesive-coated surface with a hot press roll. The surface temperature of the heating roll was 100 ° C., the pressing speed was 5 m / min, and the pressing pressure was 3 kg / cm. The obtained copper-clad laminated film was thermally cured at 80 ° C. for 2 days and at 100 ° C. for 5 hours.

(3) Printed wiring board After the copper foil surface of the copper-clad laminate film obtained above is washed with ethanol, it is masked with a polyester adhesive tape (57-H-UL, manufactured by Nichiban Co., Ltd., 50 μm thickness), and the copper width is 1 mm. The printed wiring board was obtained by etching with a 12% aqueous solution of ferric chloride in a grid pattern with an etching interval of 5 mm.

Comparative Example 6
One side of the PPS film-1 of Comparative Example 1 was subjected to a corona discharge treatment of 6000 J / m ² , and a copper foil was laminated on the corona treated surface in the same manner as in Example 7 to produce a printed wiring board (wiring board— 7).

Comparative Example 7
One side of the intermediate laminated film-1 prepared in Comparative Example 2 was subjected to a corona discharge treatment of 6000 J / m ² , and a copper foil was laminated on the corona treated surface in the same manner as in Example 7 to prepare a printed wiring board ( Wiring board-8).

Comparative Example 8
A printed wiring circuit was prepared on one side of the laminated film-7 obtained in Comparative Example 3 in the same manner as in Example 7 (referred to as wiring board-9).

Comparative Example 9
A printed wiring circuit was formed on one side of the laminated film-8 prepared in Comparative Example 4 in the same manner as in Example 7. Let the obtained printed wiring board be wiring board-10.

  The results of evaluation of each example and comparative example are shown in comparison with Tables 2 and 3.

(Summary)
Tables 2 and 3 show the evaluation results of the laminated film of the present invention. The laminated film of the present invention has maintained the excellent characteristics of PPS and has improved the solder heat resistance, adhesion and thermal dimensional stability (warping), which have been the conventional problems, and has become an optimal material for printed wiring boards. That is, each characteristic of mechanical characteristics, flame retardancy, and moisture absorption is compared with the PPS film-1 of Comparative Example 1 in which the laminated film-1 of Example 1 to the laminated film-6 of Example 6 of the present invention is a single PPS or a comparison. When compared with the intermediate laminated film-1 of Example 2, it was almost at the same level as the characteristics of the single PPS (Table 2). Further, it can be seen from the evaluation results in Table 3 that the frequency dependence of dielectric characteristics, which is another advantageous characteristic, is small and stable. In addition, it can be seen that conventional problems such as solder heat resistance, adhesion, and warpage (thermal dimensional stability) have been solved. Further, it can be seen that the conventional polyimide film (Comparative Example 5) is excellent in solder heat resistance and thermal dimensional stability, but has a large change in dielectric characteristics in the high frequency region, and is difficult to apply to high frequency.

  Further, the configuration proposed in Patent Document 1 (laminated film-7 of Comparative Example 3) improves the warpage indicating the degree of solder heat resistance and thermal dimensional stability, but it is well understood that the adhesion is weak. . This is because the cohesive PPS layer was laminated on the surface of the p-PPS layer because the adhesiveness was improved by the constitution of the laminated film of the present invention. Comparing the characteristics of the intermediate laminated film of Comparative Example 2 with the laminated film of the present invention, it can be seen that the C layer is necessary from the viewpoint of improvement in solder heat resistance and warpage. Further, the C layer is obtained by comparing the laminated film-8 of Comparative Example 4 with the laminated film of the present invention shown in the Examples, unless the heat resistant resin layer having substantially no melting point as used in the present invention is used. You can also see that the sled cannot be improved.

  The laminated film of the present invention is characterized in that a copolymerized PPS layer is laminated on at least one surface of a biaxially oriented p-PPS film, but all repeating p-phenylene sulfide units contained in the copolymerized PPS resin. Content represented by mol% with respect to the unit is PPSF (B), and content represented by mol% with respect to all repeating units of copolymerized units contained in the B layer of the laminated film of the present invention after the p-phenylene sulfide. It can also be seen from the results of Examples 2 to 6 that, when the amount is COPF (B), satisfying Expressions 1 and 2 is necessary in terms of adhesion, solder heat resistance, and warpage. That is, when the content of the copolymerized PPS increases, the solder heat resistance and thermal dimensional stability (warp) tend to decrease, and conversely, when the content of the copolymerized PPS decreases, the adhesion tends to decrease.

  The laminated film of the present invention has a B layer and a C layer on both sides of the biaxially oriented p-PPS film as can be seen by comparing the laminated film 1 of Example 1 and the laminated film 4 of Example 4. It is easier to achieve the object of the present invention by laminating in order.

  Next, the results of evaluation are shown in Table 4 for the printed wiring board of the present invention. It can be seen that the printed wiring boards based on the laminated films of Examples 7 to 12 of the present invention have both improved solder heat resistance and adhesion. A film based on a single PPS film or a C-layer heat-resistant resin having a melting point or glass transition point has a problem in solder heat resistance. Further, it can be seen that the wiring board-9 based on the laminated film proposed in Patent Document 1 has difficulty in adhesion and has a result according to the evaluation result of the laminated film.

The present invention relates to a laminated film using a PPS film. More specifically, it is a laminated film of a PPS film, a copolymerized PPS layer, and a polymer resin layer having substantially no melting point, and particularly based on the laminated film most suitable for an insulating material of a printed wiring board and the laminated film. The present invention relates to a printed wiring board.

Claims (3)

Containing at least one copolymer unit other than the p-phenylene sulfide unit on at least one surface of the biaxially oriented film (A layer) comprising a resin composition containing poly-p-phenylene sulfide as a main component; A layer characterized in that a layer (B layer) composed of copolymerized polyphenylene sulfide satisfying the following formulas 1 and 2 and a polymer resin layer (C layer) having substantially no melting point are laminated in this order. the film.
50 ≦ PPSF (B) ≦ 95 Formula 1
3 ≦ COPF (B) <50 Formula 2
PPSF (B): Content (mol%) of p-phenylene sulfide unit in B layer with respect to all repeating units
COPF (B): Content (mol%) of copolymerized units contained in the B layer after the p-phenylene sulfide units in the second layer with respect to all repeating units 2. The laminated film according to claim 1, wherein the C layer is a layer made of an aromatic polymer. A printed wiring board, wherein an electric circuit is formed on at least one surface of the surface of the C layer of the laminated film according to claim 1.