JP2005081792A - Polyphenylene sulfide resin film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin film, particularly using a polyphenylene sulfide (PPS) resin as a constituent, which has a low thermal/humidity expansion coefficient, can be stuck by heating and is excellent in soldering resistance and heat resistance. <P>SOLUTION: This heat resistant polyphenylene sulfide resin film comprises a complex prepared by laminating a polyphenylene sulfide resin layer and a thermoplastic resin nonwoven fabric. A ratio of the thickness (D[μm]) of polyphenylene sulfide resin layer to the basis weight (W[g/m<SP>2</SP>]) of thermoplastic resin nonwoven fabric, that is, a thickness/basis weight ratio (D/W[μm×m<SP>2</SP>/g]) is ≥0.1 but ≤1.7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a new and industrially useful resin film having heat-resistant properties.

  More specifically, the present invention relates to a polyphenylene sulfide (PPS) resin film comprising a polyphenylene sulfide (PPS) resin as a constituent material.

  More specifically, for example, the PPS resin film of the present invention relates to a PPS resin film that can be suitably used as a multilayer laminated board constituting a circuit board by laminating the PPS resin film and a copper foil.

  Conventionally, as a heat-resistant resin film, a polyimide resin film, a liquid crystal resin film, or a film containing glass fiber or an inorganic substance therein is well known.

  These resin films are resin films excellent in high heat resistance, low linear expansion coefficient, high insulation, low moisture absorption, high gas barrier properties, high strength, and the like, and have been put into practical use in circuit board applications and the like. In addition, a printed wiring board for IC using the resin film has been developed and put into practical use.

  A polyphenylene sulfide (PPS) resin film that has been heat-aged to improve heat resistance has also been studied.

  In addition, a film in which a liquid crystal resin film is impregnated with a thermosetting resin has been studied.

  However, among the above, the polyimide resin film has good thermal dimensional stability but poor hygroscopic dimensional stability, and the dimensional change under high humidity is severe. The dimensional change like the IC printed wiring board However, there is a drawback that the use is limited, and there is also a serious disadvantage that a multilayer substrate cannot be formed by bonding with a copper foil by a heat bonding method.

  For this reason, liquid crystal resin films having excellent thermal dimensional stability and hygroscopic dimensional stability and having thermal adhesiveness have been used.

  However, for liquid crystal resin films, whatever type of liquid crystal resin is used, and even if a single-layer film or a laminated film with another resin is intended, extrusion and moldability are extremely high. bad. In addition, the adhesiveness to the metal foil is poor, and even if a thermoplastic resin porous body is introduced between the metal foil and the liquid crystal resin film, it is very difficult to obtain a product in which the metal foil and the liquid crystal resin film are firmly bonded. There was a big problem in practical use.

  In addition, a polyphenylene sulfide (PPS) resin film that has been heat-aged for a long time does not have a coefficient of thermal expansion of 20 ppm or less, and when thermally bonded to a metal foil, it cannot be used by curling and is also expensive to manufacture. The actual situation is that it cannot be used in practice.

  In addition, a film in which a liquid crystal resin nonwoven fabric is impregnated with a thermosetting resin has a drawback that a multilayer substrate cannot be formed by laminating copper foil by a heat bonding method.

As a conventional technique as described above, for example, in molding a liquid crystal resin film alone, the extrudability and stretchability are inferior. ) Laminate improved extrusion stretchability (Patent Document 1), and liquid crystal resin added with a small amount (20-40%) of PPS resin (Patent Document 2). In addition, a small amount (0.1 to 40% by weight) of a liquid crystal resin having a low viscosity of 0.1 to 50 Pa · sec is added to the PPS resin to improve quality such as thickness unevenness (Patent Document 3). It has been. Further, as a method for improving the adhesive strength between the liquid crystal resin film and the metal foil, a method of introducing a thermoplastic resin porous body between the liquid crystal resin film and the metal foil (Patent Document 4) is known. As a film in which a liquid crystal resin nonwoven fabric is impregnated with a thermosetting resin, a film (Patent Document 5) in which a liquid crystal resin nonwoven fabric is impregnated with a water-soluble epoxy resin is known.
Japanese Patent Laid-Open No. 14-29002 Japanese Patent Laid-Open No. 14-179934 JP-A-10-130389 JP-A-9-76417 JP 2000-192809 A

  As described above, the object of the present invention has been to provide a heat-resistant resin film having a low temperature / humidity expansion coefficient, heat bonding, excellent adhesion strength to metal foil, and excellent solder resistance. In view of the absence, it is an object to provide a new and industrially useful heat-resistant resin film having such characteristics.

  Another object of the present invention is to provide a metal foil laminated heat resistant resin film in which, for example, a metal foil such as copper is typically laminated on the heat resistant resin film. An object of the present invention is to provide a multilayer laminate in which a plurality of metal foil laminated heat-resistant resin films are used and further laminated and thermally bonded by heating.

The polyphenylene sulfide (PPS) resin film of the present invention has the following structures (1) to (6).
(1) As a result of earnest studies to obtain a heat-resistant resin film, it is a polyphenylene sulfide resin film comprising a composite in which a polyphenylene sulfide resin layer and a thermoplastic resin nonwoven fabric are laminated, and the thickness of the polyphenylene sulfide resin layer (D [μm]) The thickness basis weight ratio (D / W [μm · m ² / g]), which is the ratio to the thermoplastic resin nonwoven fabric basis weight (W [g / m ² ]), is 0.1 or more and 1.7 or less. Polyphenylene sulfide resin film.
(2) The polyphenylene sulfide resin film according to claim 1, wherein the thickness basis weight ratio (D / W [μm · m ² / g]) is 0.2 or more and 1.5 or less.
(3) The polyphenylene sulfide resin film according to (1) or (2), wherein the polyphenylene sulfide resin has a melt viscosity of 100 poise or more and 4000 poise or less.
(4) The polyphenylene sulfide resin film according to any one of (1) to (3), wherein the thermoplastic resin nonwoven fabric has a thermal expansion coefficient α of 10 ppm / ° C. or less.
(5) The polyphenylene sulfide resin film according to any one of (1) to (4), wherein the thermoplastic resin nonwoven fabric is a liquid crystalline resin nonwoven fabric.
(6) The polyphenylene sulfide resin film according to any one of (1) to (5), which has a thermal expansion coefficient α of 20 ppm / ° C. or less.
(7) The polyphenylene sulfide resin film according to any one of (1) to (6), which has a solder heat resistance temperature of 260 ° C. or more for 60 seconds or more.
Moreover, the metal foil laminated polyphenylene sulfide (PPS) resin film of the present invention has the following structures (8) to (9).
(8) A metal foil laminated polyphenylene sulfide resin film obtained by laminating a metal foil on the polyphenylene sulfide resin film according to any one of the above (1) to (7).
(9) The metal foil laminated polyphenylene sulfide resin film as described in 8, wherein the metal foil is a copper foil.

Moreover, the multilayer laminated board of this invention has a structure as the following (10).
(10) A multilayer laminate comprising a metal foil laminated polyphenylene sulfide (PPS) resin film in which a plurality of metal foil laminated polyphenylene sulfide resin films according to (8) or (9) are laminated.

It consists of a composite in which a polyphenylene sulfide (PPS) resin layer and a thermoplastic resin nonwoven fabric are laminated, and (the thickness of the polyphenylene sulfide (PPS) resin layer (μm)) (the basis weight of the thermoplastic resin nonwoven fabric (g / m ² )) By setting the ratio to 0.1 to 1.7, it is possible to provide a PPS film excellent in thermal adhesiveness and dimensional stability at high temperatures. In particular, for example, a PPS film having a dramatically improved thermal expansion coefficient α of 20 ppm or less and good solder heat resistance can be realized.

  The PPS film concerning this invention can be preferably used as industrial materials, such as a multilayer circuit board use by which the thermal adhesiveness and dimensional stability at high temperature are requested | required. Furthermore, the film thus obtained has good heat resistance and can be used well for various uses other than circuit boards.

  The PPS resin film according to the present invention that is preferably configured can be heat-bonded at a high temperature of, for example, 250 ° C. to 350 ° C., and has an average coefficient of thermal expansion up to about 200 ° C. as a typical characteristic example. It is possible to realize excellent properties of 20ppm / ° C or less, solder heat resistance at 260 ° C for 60 seconds or more, and when it is thermally bonded to copper foil, it does not curl and peel strength is 600g / cm or more. The present invention relates to an industrially very useful PPS resin film.

  Hereinafter, preferred embodiments of the present invention will be described.

  The polyphenylene sulfide (PPS) resin referred to in the present invention is a poly-para (poly (para) (as represented by Japanese Patent No. 2924202, Japanese Patent No. 2814505, Japanese Patent Publication No. 63-35406, Japanese Patent No. 2722577, etc.). A resin containing P) -phenylene sulfide as a main component, preferably a resin containing 70 mol% or more of para (P) -phenylene sulfide repeating units. The resin containing 70 mol% or more is preferable because the properties less than that are inferior to those intended by the present invention, such as heat resistance, dimensional stability, and mechanical properties. .

  Of course, any form of poly-meta (m) -phenylene sulfide polymer and other monomers having an aryl group, biphenyl group, terphenyl group, vinylene group, carbonate group, etc. in a small amount, for example, in the range of less than 30 mol%. It may be included by (copolymerization, mixing, etc.). The molecule of the PPS resin is preferably a linear / linear polymer having a molecular weight of 50,000 or more, but is not necessarily limited to this, and even a polymer having a branched chain has a partially crosslinked structure. It may be what you did.

  The low molecular weight oligomer contained in the PPS resin can be removed by washing with a solvent such as diphenyl ether, and the amount of oligomer is preferably 1.5% by weight or less by extraction with boiling xylene for 36 hours. For the production method of these PPS resins, US Pat. No. 3,354,129 is helpful.

  Of course, polyester, polyamide, polyolefin, polyimide, polyamideimide, polyetherimide, polyarylate, polyetherimide, modified polyphenylene sulfide, polyetheretherketone, polyethersulfone, polysulfone, etc. are used as polymer alloys for the PPS resin. However, the present invention is not necessarily limited thereto. The mixing ratio with the resin is preferably within 0.1 to 30% by weight.

The melt viscosity of the PPS resin is preferably 6000 poise or less and 100 poise or more. More preferably, it is 4000 poise or less and 500 poise or more. The adhesiveness with metal foil tends to increase by being in the above range. The melt viscosity referred to in the present invention refers to a melt viscosity at 300 ° C. and a shear rate of 1000 cm ⁻¹ .

  The thermoplastic resin constituting the thermoplastic resin nonwoven fabric used in the present invention is polyester, polyamide, polyolefin, thermoplastic polyimide, polyamideimide, polyetherimide, polyarylate, polyetherimide, modified polyphenylene sulfide, polyetheretherketone, poly Ether sulfone, polysulfone, liquid crystal resin, and the like can be used, but are not necessarily limited thereto. From the viewpoint of temperature dimensional stability, polyester, thermoplastic polyimide, polyphenylene sulfide, and liquid crystalline resin are preferable, and liquid crystalline resin is particularly preferable.

  The liquid crystalline resin used in the present invention typically has a regular structure like a crystal even in a molten state such as a thermotropic liquid crystal resin, such as a resin described in JP-A-2002-294039. It refers to a resin, and conventionally known resins can be used as the liquid crystalline resin.

  Specifically, for example, in the case of a liquid crystalline polyester resin, it contains 40 to 90% by weight of a parahydroxybenzoic acid (HBA) component as a main mesogen, and 4,4′-dihydroxybiphenyl ( A liquid crystalline polyester containing DHB) is preferred. The mesogen-containing form may be any form such as random copolymerization, block copolymerization, branch copolymerization, or combination composite copolymerization thereof.

  For example, a liquid crystalline resin composed of polyethylene terephthalate (PET) or polyethylene naphthalate (PEN) / HBA / DHB / isophthalic acid (IPA), a copolymer mainly composed of HBA / 6-hydroxy-2-naphthoic acid, There are copolymers of HBA / 4,4′-dihydroxybiphenyl and terephthalic acid and isophthalic acid, and copolymers of HBA / hydroquinone (HQ) / sebacic acid (SA). An I-type liquid crystal having high heat resistance such as a group liquid crystal resin is preferable.

  In the case of the present invention, the melt viscosity of the liquid crystal resin is 60 Pa · sec or less, preferably 30 Pa · sec or more, more preferably 10 to 20 Pa · sec. Is preferable.

  Since the liquid crystalline polyester resin composed of such components is oriented in the direction in which molecules easily flow by flow during melting, a nonwoven fabric excellent in temperature dimensional stability can be obtained. Further, instead of using the liquid crystalline resin alone, a polymer alloy containing the liquid crystalline resin may be used. As an alloy polymer to be mixed or chemically bonded, it is possible to use a thermoplastic resin such as polyamide, polyimide, polyamideimide, polyetherimide, polyarylate, polyphenylene sulfide, polyetheretherketone, polyethersulfone or polysulfone. Although it can, it is not limited to these. By using a polymer alloy containing a liquid crystalline resin, excellent properties such as fluidity, moldability and toughness due to the liquid crystalline resin may be exhibited.

  The thermoplastic resin nonwoven fabric of the present invention preferably has a thermal expansion coefficient α of 10 ppm / ° C. or less from the viewpoint of curling properties when thermally bonded to a metal foil. More preferably, it is 5 ppm / ° C. or less. On the other hand, the lower limit is preferably −30 ppm / ° C., more preferably −20 ppm / ° C., and further preferably −15 ppm / ° C. or more. As a method for obtaining a nonwoven fabric having a thermal expansion coefficient α of 10 ppm / ° C. or less, it can be produced by a known method, but a melt blow method represented by JP-A-2002-61064 is preferred. The melt blow method referred to in the present invention is a method in which a thermoplastic resin is melt-spun from a nozzle, and at the same time, the resin melted by a high-pressure and high-temperature gas is blown off into a fine fiber shape and collected on a suction collecting surface represented by a wire mesh. It is a method of collecting and manufacturing.

  The average fiber diameter of the fibers constituting the thermoplastic resin nonwoven fabric of the present invention is preferably 1 to 13 μm, more preferably 3 to 7 μm. The fiber diameter here refers to an average value obtained by taking an enlarged photograph using a microscope and measuring fiber diameters at 100 points. If the value falls below the lower limit of the numerical range, the strength of the nonwoven fabric tends to be small, and not only the strength of the product itself is lowered but also handling in the subsequent process becomes difficult. Moreover, when it exceeds an upper limit, it will become the tendency for the uniformity of thickness to deteriorate, and neither is preferable.

  The thermoplastic resin nonwoven fabric of the present invention may be impregnated with a resin. The resin used for impregnation may be a thermoplastic resin with good thermal adhesiveness, or may be a thermosetting resin with a small thermal expansion coefficient. Preferred examples of the resin include an epoxy resin and a polyimide resin.

  The film concerning this invention is a polyphenylene sulfide (PPS) resin film which consists of a composite body by which this polyphenylene sulfide (PPS) resin layer and the nonwoven fabric which consists of this thermoplastic resin were laminated | stacked.

  The laminated structure is not particularly limited, but a polyphenylene sulfide (PPS) resin layer may be laminated on one or both sides of the polyphenylene sulfide (PPS) resin layer, and the polyphenylene sulfide (PPS) resin layer on both sides of the thermoplastic resin nonwoven fabric May be laminated. Moreover, in order to give bending resistance and handleability, a polyphenylene sulfide (PPS) resin layer and a thermoplastic resin nonwoven fabric layer may be alternately laminated in four or more layers. A configuration in which a polyphenylene sulfide (PPS) resin layer is laminated on one surface or both surfaces of a thermoplastic resin nonwoven fabric is preferable. In addition, when a PPS resin layer (or nonwoven fabric) is a multilayer, parameters, such as the thickness (weight per unit area), shall be the sum of each layer of a PPS resin layer (or nonwoven fabric).

  The laminated interface of the composite of the present invention may have a region where polyphenylene sulfide (PPS) resin and thermoplastic resin nonwoven fabric are mixed, but the mixed region is the thickness of the nonwoven fabric, preferably 70 (more The thickness is preferably 50, more preferably 25)% or less. This is because the linear thermal expansion coefficient tends to increase when the above is exceeded.

  The composite according to the present invention may contain other components as long as the effects of the present invention can be achieved.

In any case, according to various findings of the present inventors, the composite has a basis weight (W [g / m] of a thermoplastic resin nonwoven fabric having a thickness (D [μm]) of a polyphenylene sulfide (PPS) resin layer. ² ]) is important that the thickness basis weight ratio (D / W [μm · m ² / g]) is not less than 0.1 and not more than 1.7 (hereinafter, the parameter is simply referred to as thickness basis weight ratio). Preferably it is 0.2 or more and 1.5 or less, More preferably, it is 0.3 or more and 1.2 or less The effect of this invention can be acquired by being in the said range.

  Of course, at least one side of the PPS film of the present invention, preferably both sides, is coated with another layer such as a thermoplastic polyimide layer to give more preferable characteristics such as surface smoothness and improved adhesion. In fact, it is often preferable to actually make such a further applied structure. Since the polyphenylene sulfide resin film of the present invention is more preferable for circuit board applications, the thickness of the composite film of the present invention is generally 20 to 350 microns, particularly 20 to 100 μm for multilayer laminates. A thin film is preferable, and 30 to 80 μm is more preferable. When used as a single film, it is preferably as thick as 100 to 350 μm.

  According to various studies conducted by the present inventors, the thermal expansion coefficients of PPS resin films that have been commercially available even today are 70 to 200 ppm / ° C. for unstretched films and 30 to 120 ppm for biaxially stretched PPS films. The PPS film generally has a large value of about / ° C., and a PPS film having such a large thermal expansion coefficient is overlapped with a copper foil having a small thermal expansion coefficient of about 17 ppm. When it is heated and bonded at a temperature of about 290 to 320 ° C. above the melting point and cooled to room temperature, the laminate curls with the PPS film inside, and cannot be put to practical use. This is considered to be because the thermal expansion coefficient of the PPS film at a high temperature is larger than that of the metal foil, and the shrinkage amount of the PPS film from the thermal bonding temperature to room temperature is larger than the shrinkage amount of the metal foil. .

  Therefore, the PPS film has been required to be as small as the metal expansion coefficient. However, even if the PPS film was subjected to heat treatment, oxidative crosslinking treatment, or even changing the stretching conditions, the coefficient of thermal expansion was not as small as that of the metal foil. Thus, as in the present invention, a PPS film having a small thermal expansion coefficient comparable to that of a metal was obtained only by forming a PPS film combined with a thermoplastic resin nonwoven fabric. The film of the present invention has a thermal expansion coefficient α. Has achieved an excellent characteristic of 20 ppm or less, preferably 15 ppm or less, more preferably 10 ppm or less. In addition, according to the knowledge of the present inventors, the lower limit of the thermal expansion coefficient α of the film of the present invention is around 5 ppm.

The PPS film of the present invention has a hygroscopic expansion coefficient β of preferably 10 (× 10 ⁻⁶ /% RH) or less, more preferably 5 (× 10 ⁻⁶ /% RH) or less. This has a very good effect in preventing malfunction due to deformation of the IC substrate film due to a change in humidity under the usage environment when used as a substrate film. According to the knowledge of the present inventors, the lower limit of the hygroscopic expansion coefficient β of the film of the present invention is around 3 (× 10 ⁻⁶ /% RH).

  In addition, the thermal deformation start temperature of a commercially available PPS film is about 90 ° C. near its glass transition temperature Tg, but it is usually desired that it is 240 ° C. or higher, preferably 260 ° C. or higher for circuit board applications. ing. This is because the solder (solder) bath temperature is as high as 240 to 260 ° C., and in some cases 300 ° C. or higher when soldering for applications such as an IC substrate, and therefore the conventional PPS is used in this high temperature solder bath. Substrate films that use film are instantly shrunk, deformed, curled, partially melted, etc., and cannot be used for various applications such as the IC substrate. For this reason, it is important for the solder heat resistance of the substrate film to have sufficient heat resistance characteristics even at 240 ° C. or higher, more preferably 260 ° C. or higher. On the other hand, the PPS film according to the present invention has such a temperature. The thermal dimensional deformation rate at 240 to 260 ° C. is preferably 0.1% or less, more preferably 0.02% or less, and it is extremely important to have such characteristics. The PPS film of the present invention having such characteristics preferably has a solder heat resistance temperature described later of 260 ° C. for 60 seconds or more.

  As a method for producing the PPS film according to the present invention combined with such a liquid crystalline resin, a polyphenylene sulfide (PPS) resin can be used in a configuration in which a polyphenylene sulfide (PPS) resin and the thermoplastic resin nonwoven fabric are combined. For example, specifically, it can be achieved by forming a composite as a laminate of a polyphenylene sulfide (PPS) resin film layer and a non-woven fabric made of a liquid crystalline resin. is there.

  Of course, at least one side, preferably both sides, of these PPS films are coated with another layer such as a thermoplastic polyimide layer that is not a composite with a liquid crystal resin, which is preferable for improving surface smoothness and adhesion. As described above, there are many cases.

  When the PPS film is produced according to the present invention, the PPS resin itself can be produced by a known method. That is, for example, sodium sulfide and p-dichlorobenzene are reacted at high temperature and high pressure in an amide polar solvent such as N-methyl-2-pyrrolidone (NMP). If necessary, a copolymer component such as trihalobenzene can be included. As a polymerization degree adjusting agent, caustic potash, an alkali metal carboxylate or the like is added and a polymerization reaction is performed at 230 to 280 ° C. After the polymerization, the polymer is cooled, and the polymer is filtered as a water slurry through a filter to obtain a granular polymer. This is stirred in an aqueous solution such as acetate at 30 to 100 ° C. for 10 to 60 minutes, washed and dried several times at 30 to 80 ° C. with ion-exchanged water to obtain a PPS powder. The powder polymer is washed with NMP at an oxygen partial pressure of 10 torr or less, preferably 5 torr or less, then washed several times with ion exchange water at 30 to 80 ° C., and dried under a reduced pressure of 5 torr or less.

  Since the melt crystallization temperature Tmc of the polymer thus obtained is in the range of 160 to 190 ° C., stable stretch film formation becomes possible. As required, other high molecular compounds, silicon oxide, magnesium oxide, calcium carbonate, titanium oxide, aluminum oxide, crosslinked polyester, crosslinked polystyrene, mica, talc, kaolin, and other inorganic and organic compounds, thermal decomposition inhibitors, heat Stabilizers and antioxidants may be added.

  In order to remove foreign substances in the raw material after supplying the PPS raw material thus obtained to a conventionally known single-screw extruder or twin-screw extruder and melting it under reduced pressure with little oxygen, Is extruded while appropriately filtering through a filter, for example, a sintered metal, a porous ceramic, sand, a wire mesh, or the like. Then, after cooling with a gear pump, the cooling medium such as a drum is discharged on the cooled drum by electrostatic application method, air chamber method, air knife method, press roll method, etc., which are known adhesion means. It is possible to obtain an unoriented amorphous film by tightly cooling and solidifying it and rapidly cooling it to room temperature.

  The film used for the PPS resin layer may be an unoriented amorphous film thus obtained, or a biaxially stretched film.

  As the biaxial stretching method, sequential biaxial stretching can be used. In the case of sequential biaxial stretching, the obtained non-oriented amorphous film is contact-heated on a roll group heated to 90 to 130 ° C., stretched 1 to 4 times in the longitudinal direction, and cooled once. After that, the end of the film is bitten by a tenter clip and stretched 2 to 6 times at 100 to 160 ° C. in the width direction to obtain a uniaxially or biaxially oriented PPS film.

  Of course, the above is an example, and the stretching method is not particularly limited, and a method such as a simultaneous biaxial stretching method, a width direction uniaxial stretching method, etc. can be used even if it is not a sequential two-time stretching method, As a driving method of the film gripping clip at this time, a chain driving method, a screw method, a pantograph method, a linear motor driving method (Japanese Examined Patent Publication No. Sho 63-12772) or the like can also be adopted.

  Subsequently, heat treatment may be performed at 200 to 280 ° C. for about 10 to 100 seconds.

  As a method for setting the peel strength with the metal foil to 600 g / cm or more, the crystallinity of the obtained unoriented amorphous film and / or biaxially oriented film is preferably 0% or more and 30% or less, more preferably It is preferably 10% or more and 20% or less. As a method for obtaining a biaxially stretched film having a crystallinity of 0% or more and 30% or less, a heat treatment temperature of 150 ° C. or less, more preferably 80 ° C. or less is preferably used.

  The PPS resin layer preferably contains substantially no non-woven fabric in the inside thereof except in the vicinity of the boundary with the non-woven fabric. The thickness of the PPS resin layer is preferably 2 to 40 (more preferably 2 to 35, still more preferably 2 to 15) μm. When the value falls below the lower limit of the numerical range, the adhesiveness of the etched portion when the multilayer laminated circuit board is constructed tends to be deteriorated. On the other hand, when the value exceeds the upper limit, the thermal expansion coefficient tends to increase, which is not preferable. The thickness of the PPS resin layer can be measured by the following method. That is, a cut surface is created so that the PPS resin film is not deformed, the thickness of the 10-point PPS resin layer is measured from a cross-sectional photograph taken using an optical reflection microscope, and the average value is taken as the thickness of the PPS resin layer.

In the film of the present invention, the parameter having an effect substantially similar to the thickness of the PPS resin is a unit corresponding to a basis weight expressed by a nonwoven fabric, that is, a weight [g] per 1 m ² , which is preferably 3 to 3 60 (more preferably 3 to 40, still more preferably 3 to 30) g / m ² . The basis weight ratio (W ′ / W), which is the ratio of the weight per 1 m ^{2 of the} polyphenylene sulfide resin (W ′ [g / m ² ]) to the basis weight (W [g / m ² ]) of the thermoplastic resin nonwoven fabric, is , Preferably 0.1 to 0.7 (more preferably 0.2 to 0.6, still more preferably 0.2 to 0.5).

  Examples of liquid crystalline resins include polyester resins and polyester amide resins. Specifically, “Siberus” (Toray Industries, Inc.), “Vectra” (Polyplastics Corporation), “Rod Run” (Unitika Ltd.) )), "Sumika Super" (Sumitomo Chemical Co., Ltd.), "Zider" (Nisseki Chemical), "Ueno Liquid Crystal Resin" (Ueno Pharmaceutical Co., Ltd.), etc. In the case of the present invention, it is preferable to use a wholly aromatic type I liquid crystal resin such as “Sumikasuper” having high viscosity and high heat resistance. And further, if necessary for those resins, inorganic, organic compounds and hydrolysis inhibitors such as silicon oxide, magnesium oxide, calcium carbonate, titanium oxide, aluminum oxide, crosslinked polyester, crosslinked polystyrene, mica, talc, kaolin, You may add a heat stabilizer, antioxidant, etc.

  A method for producing a nonwoven fabric from the resin thus obtained is not limited, but a melt blow method, a spun lace method, a spun bond method and the like can be used. Particularly in the case of the present invention, the thermal expansion coefficient α is 10 ppm / ° C. The melt-blowing method is the most preferable in consideration of the thickness and basis weight of the nonwoven fabric layer, the thickness of the nonwoven fabric fibers, the nonuse of the adhesive, the production cost, and the like.

  The thickness of the nonwoven fabric layer is preferably a thin film, preferably 40 μm or less, more preferably 25 μm or less. This is because the flatness tends to deteriorate during lamination. On the other hand, the thickness of the nonwoven fabric layer is preferably 5 μm or more, more preferably 10 μm or more. This is because wrinkles tend to occur easily in the nonwoven fabric manufacturing process.

Basis weight of the nonwoven fabric layer is (more preferably 15 to 60, more preferably 20 to 50) preferably 5~80 g / m ^2. If the value falls below the lower limit of the numerical range, the physical properties of the nonwoven fabric tend to be non-uniform. On the other hand, if the value exceeds the upper limit, the multilayer laminated circuit board becomes thick, which is not preferable.

  For bonding the PPS film and the nonwoven fabric layer, in order to minimize the air layer of the nonwoven fabric layer, a high temperature and high pressure which is a temperature higher than (the melting point of either the PPS resin film or the thermoplastic resin nonwoven fabric −50 ° C.) or higher. It is better to heat laminate. Preferably it is 250 to 350 degreeC. At this time, a metal foil laminated polyphenylene sulfide (PPS) resin film can be obtained by heat laminating simultaneously with the metal foil.

  In the case of the two-layer PPS film composite thus obtained, the surface to be thermally laminated with the metal foil is laminated so that the PPS resin layer side is in contact with the metal foil, adhesive force, etching for patterning, etc. This is convenient and good. The thickness of the metal foil is preferably 5 to 18 (more preferably 6 to 12) μm, particularly for IC circuit board applications.

  In addition to the above example, a copper foil laminated polyphenylene sulfide may be prepared by the following method. That is, the above-described PPS resin, liquid crystalline nonwoven fabric and copper foil are used and the extrusion lamination method is used. The laminated structure may be liquid crystal non-woven fabric / PPS film / copper foil, or PPS film / liquid crystal non-woven fabric / PPS film / copper foil, but is not limited thereto.

In the PPS resin film of the present invention, in order to make the thermal expansion coefficient α be 20 ppm or less, and particularly in order to make the solder heat-resistant temperature 60 seconds or more at 260 ° C., usually According to the knowledge of the present inventors, the thickness basis weight ratio (D / D) is the ratio of the polyphenylene sulfide (PPS) resin layer thickness (D [μm]) to the thermoplastic resin nonwoven fabric basis weight (W [g / m ² ]). W [μm · m ² / g]) is 0.1 or more and 1.7 or less.

Further, in order to make the above-described hygroscopic expansion coefficient β to be 10 (× 10 ⁻⁶ /% RH) or less, by orienting the PPS resin, it is further reduced to 5 (× 10 ⁻⁶ /% RH) or less. In order to make it exist, it can be achieved by setting the crystallinity to 10% or more.

  The PPS resin film of the present invention thus obtained has good heat resistance characteristics. For example, specifically, the thermal expansion coefficient α is 20 ppm or less, and the heat distortion temperature is 260 ° C. and 60 ° C. A PPS composite film having a small humidity expansion coefficient β can be obtained in a second or more, and has excellent thermal adhesion and flatness with a metal foil such as copper foil, and also has excellent solder resistance. For this reason, it can be used extremely effectively in applications requiring thermal adhesiveness and heat resistance, such as a base film for multilayer lamination for IC circuit boards.

  That is, a preferred application mode of the PPS resin film of the present invention is a metal foil laminated PPS resin film in which a metal foil is thermally bonded to the film by heating, and more specifically, the metal foil is a copper foil. It is a laminated film. Further, as an application mode thereof, a PPS resin film formed by using a plurality of metal foil laminated PPS resin films according to the present invention, further laminating them, and thermally bonding them by heating to form a laminated plate It is a multilayer laminated board which consists of. In the case of such a multilayer laminate, the metal foil layers are often electrically connected with a conductive material passing through the layers as necessary.

Although the PPS resin film concerning this invention changes with uses and is not specifically limited, Generally the thing of the range of 20-350 micrometers is used as the most suitable thing. In particular, in the field of multilayer circuit boards, the thickness is preferably in the range of 20 to 100 [mu] m, more preferably in the range of 30 to 80 [mu] m, in order to overlap many sheets. The PPS resin film of the present invention, which has such a thickness and can achieve heat resistance as described above, is very new and useful as a thin film circuit board that can be realized even when used for a multilayer laminated board. And industrial value is great.
[Measurement method of physical properties]
Next, the measurement method used in the present invention will be described below.

In the following measurements, the numerical data is averaged by taking n as 10.
1. Thermal expansion coefficient α (× 10 ⁻⁶ / ° C.):
A sample is cut out to a width of 5 mm, and the distance between chucks is set to 150 mm with a constant load elongation tester (Nippon Automatic Control Co., Ltd. constant load elongation tester) set in a constant temperature and humidity chamber (PKL-50D manufactured by Daiei Chemical Co., Ltd.). When the sample is sandwiched in, heated to 30-230 ° C. at a rate of 2 ° C./min in 65 RH%, and lowered to 230-30 ° C. at a rate of 2 ° C./min. It was determined from the average slope of the deformation amount ΔL up to (ΔT = 170 ° C.). According to ASTM D696. α = (ΔL / L) / ΔT ° C., and the unit is 10 ⁻⁶ / ° C. ppm.
2. Humidity expansion coefficient β (× 10 ⁻⁶ /% RH):
A sample is cut out to a width of 10 mm, and the distance L between chucks becomes 150 mm with a constant load elongation tester (Japan Automatic Control Co., Ltd. constant load elongation tester) set in a constant temperature and humidity chamber (PKL-50D manufactured by Daiei Chemical Co., Ltd.). Thus, the sample was sandwiched in the manner described above, and the amount of deformation ΔL when humidified from 5 RH% to 85 RH% at 25 ° C. (ΔRH = 80 RH%) was obtained by the following equation.

β = (ΔL / L) / ΔRH, and the unit is 10 ⁻⁶ /% RH.
3. Adhesion (peel strength):
A sample in which a PPS film and a 12 μm copper foil were superposed and thermally bonded with a heating roll at 280 ° C. and a linear pressure of 40 kgf / cm was measured according to JIS C6471-1990 6.5A method.
4). Solder resistance:
A sample in which a PPS film and a 12 μm copper foil were superposed and thermally bonded with a heating roll at 280 ° C. and a linear pressure of 40 kgf / cm was determined according to JIS C5012-1993. Specifically, after the sample is floated in a solder bath at 260 ° C. for 60 seconds, abnormalities such as discoloration and swelling are visually confirmed.
5). Curl property:
A sample in which a PPS film and a 12 μm copper foil are superposed and thermally bonded with a heating roll at 280 ° C. and a linear pressure of 40 kgf / cm is calculated according to the warp rate of JIS C6471-1990, and 5% or less is ○ And the others were marked with x.

  Using PPS resin (type 1881) manufactured by Toray Industries, Inc., 0.12% by weight of “Syloid” 300 and 0.05% by weight of calcium stearate were added as additives. “Sumika Super” (E6000) was used as the liquid crystal resin.

  After the PPS resin was melted at 310 ° C. under high shear, the PPS resin was passed through a filtration box that cuts foreign matters of 10 μm or more, and extruded from a T-die die having a lip width of 450 mm and a lip gap of 0.6 mm.

  An electrostatic charge was applied to the melted film thus extruded, and it was closely cooled and solidified on a casting drum (diameter 800 mm) having a surface temperature of 25 ° C. A PPS monolayer film was obtained. The crystallinity of the film was 1% or less.

A melt blown nonwoven fabric made of liquid crystal resin having an apparent thickness of 40 μm, a fiber diameter of 10 μm, and a basis weight of 25 g / m ² was prepared by melt blowing the liquid crystal resin. This non-woven fabric made of liquid crystal resin and the PPS single layer film / liquid crystal resin non-woven fabric (thickness weight ratio: 1.2) on which the PPS single layer film was laminated were adhered by a thermocompression bonding method at 250 ° C. to obtain a PPS resin film. The thickness of the PPS layer of the obtained PPS resin film was 25 μm. Further, a copper foil having a thickness of 12 μm was adhered to the PPS film surface by thermocompression bonding to obtain a composite having a laminated structure of copper foil / PPS film / non-woven fabric made of liquid crystal resin.

  The metal stay laminated film thus obtained has good curling properties and excellent peel strength. The characteristics of the film are as follows.

Polyphenylene sulfide (PPS) resin film Thermal expansion coefficient α: 20 ppm / ° C.
Humidity expansion coefficient β: 3 ppm /% RH
Copper foil laminated polyphenylene sulfide (PPS) resin film Adhesiveness (peel strength): 800 g / cm
Solder resistance: ○ (Good)
Curl property: ○ (Good)

  After the PPS resin used in Example 1 was melted at 310 ° C. under high shear, the PPS resin was passed through a filtration box that cuts foreign matters of 10 μm or more, and a film was formed from a T die die having a lip width of 450 mm and a lip gap of 0.6 mm. Extruded.

  An electrostatic charge was applied to the melted film thus extruded, and it was closely cooled and solidified on a casting drum (diameter 800 mm) having a surface temperature of 25 ° C. The film was supplied to a longitudinal stretching machine consisting of a heated roll group, stretched 3.5 times at a film temperature of 100 ° C., and then stretched 4 times at 100 ° C. in the width direction using a tenter. A PPS film was obtained. The crystallinity of the film was 5%.

  A polyphenylene sulfide (PPS) resin film and a copper foil laminated polyphenylene sulfide (PPS) resin having the same structure as the PPS film / non-woven fabric made of liquid crystal resin (thickness weight ratio: 1.2) using the liquid crystalline nonwoven fabric used in Example 1 A film was obtained. The thickness of the PPS resin layer of the obtained PPS resin film was 25 μm. Furthermore, in the copper foil laminated PPS resin film, two circuits shown in FIG. 1.1F with JIS C5012-1993 were prepared and adhered by a thermocompression bonding method at 280 ° C. to prepare a multilayer laminated substrate.

  The metal stay laminated film thus obtained has good curling properties and excellent peel strength. Further, it was not possible to peel off between the layers in the multilayer laminated substrate. The characteristics of the film are as follows.

Polyphenylene sulfide (PPS) resin film Thermal expansion coefficient α: 18 ppm / ° C.
Humidity expansion coefficient β: 1 ppm /% RH
Copper foil laminated polyphenylene sulfide (PPS) resin film Adhesiveness (peel strength): 600 g / cm
Solder resistance: ○ (Good)
Curl property: ○ (Good)
Multilayer laminate Adhesiveness: 2000 g / cm or more Solder resistance: ○ (Good)
Curl property: ○ (Good)

  A PPS film having a thickness of 15 μm was obtained in the same manner as in Example 2. The crystallinity of the film was 4%.

  Using the liquid crystalline nonwoven fabric used in Example 1, a polyphenylene sulfide (PPS) resin film and a copper foil laminated polyphenylene sulfide (PPS film / nonwoven fabric made of liquid crystal resin / PPS film (thickness ratio is 1.2)) A PPS resin film was obtained.

  The metal stay laminated film thus obtained has good curling properties and excellent peel strength. The characteristics of the film are as follows.

Polyphenylene sulfide (PPS) resin film Thermal expansion coefficient α: 14 ppm / ° C.
Humidity expansion coefficient β: 1 ppm /% RH
Copper foil laminated polyphenylene sulfide (PPS) resin film Adhesiveness (peel strength): 700 g / cm
Solder resistance: ○ (Good)
Curl property: ○ (Good)

  A PPS film having a thickness of 8 μm was obtained in the same manner as in Example 2. The crystallinity of the film was 4%.

  A polyphenylene sulfide (PPS) resin film and a copper foil laminated polyphenylene sulfide (PPS film / non-woven fabric made of liquid crystal resin / PPS film (thickness areal ratio is 0.6)) and a copper foil laminated polyphenylene sulfide (using the liquid crystalline nonwoven fabric used in Example 1) A PPS resin film was obtained.

  The metal stay laminated film thus obtained has good curling properties and excellent peel strength. The characteristics of the film are as follows.

Polyphenylene sulfide (PPS) resin film Thermal expansion coefficient α: 10 ppm / ° C.
Humidity expansion coefficient β: 1 ppm /% RH
Copper foil laminated polyphenylene sulfide (PPS) resin film Adhesiveness (peel strength): 750 g / cm
Solder resistance: ○ (Good)
Curl property: ○ (Good)

  Copper foil laminated polyphenylene sulfide (PPS resin, liquid crystalline nonwoven fabric and copper foil used in Example 1 laminated with liquid crystal resin nonwoven fabric / PPS film / copper foil (thickness weight ratio is 1.2) by extrusion lamination method) A PPS resin film was obtained. The copper foil was removed by etching to obtain a polyphenylene sulfide (PPS) resin film.

  The metal stay laminated film thus obtained has good curling properties and excellent peel strength. The characteristics of the film are as follows.

Polyphenylene sulfide (PPS) resin film Thermal expansion coefficient α: 20 ppm / ° C.
Humidity expansion coefficient β: 3 ppm /% RH
Copper foil laminated polyphenylene sulfide (PPS) resin film Adhesiveness (peel strength): 900 g / cm
Solder resistance: ○ (Good)
Curl property: ○ (Good)
[Comparative Example 1]
The film characteristics were evaluated using only the PPS monolayer film used in Example 1. Similarly, the result of obtaining a metal foil laminated PPS film by thermally bonding with a copper foil is as follows and could not satisfy the object of the present invention.

Polyphenylene sulfide (PPS) resin film Thermal expansion coefficient α: 100 ppm / ° C.
Humidity expansion coefficient β: 3 ppm /% RH
Copper foil laminated polyphenylene sulfide (PPS) resin film Adhesiveness (peel strength): 800 g / cm
Solder resistance: ○ (Good)
Curl property: × (defect)
[Comparative Example 2]
A film was prepared in the same manner as in Example 1 except that the thickness of the PPS layer of the PPS resin film was 45 μm (thickness ratio is 1.8).

Polyphenylene sulfide (PPS) resin film Thermal expansion coefficient α: 50 ppm / ° C.
Humidity expansion coefficient β: 3 ppm /% RH
Copper foil laminated polyphenylene sulfide (PPS) resin film Adhesiveness (peel strength): 800 g / cm
Solder resistance: ○ (Good)
Curl property: × (defect)

The PPS resin film of the present invention can be used for a PPS resin film that can be suitably used as a multilayer laminated plate constituting a circuit board by laminating the PPS resin film and a copper foil.

Claims (10)

A polyphenylene sulfide resin film comprising a composite of a polyphenylene sulfide resin layer and a thermoplastic resin nonwoven fabric laminated, and the thermoplastic resin nonwoven fabric weight (W [g / m ² ]) having a polyphenylene sulfide resin layer thickness (D [μm]) A polyphenylene sulfide resin film having a thickness basis weight ratio (D / W [μm · m ² / g]) of 0.1 to 1.7. ^2. The polyphenylene sulfide resin film according to claim 1, wherein a thickness basis weight ratio (D / W [μm · m ² / g]) is 0.2 or more and 1.5 or less. The polyphenylene sulfide resin film according to claim 1 or 2, wherein the polyphenylene sulfide resin has a melt viscosity of 100 poise or more and 4000 poise or less. The polyphenylene sulfide resin film according to claim 1, wherein the thermoplastic resin nonwoven fabric has a thermal expansion coefficient α of 10 ppm / ° C. or less. The polyphenylene sulfide resin film according to any one of claims 1 to 4, wherein the thermoplastic resin nonwoven fabric is a liquid crystalline resin nonwoven fabric. The polyphenylene sulfide resin film according to claim 1, which has a thermal expansion coefficient α of 20 ppm / ° C. or less. The polyphenylene sulfide resin film according to claim 1, which has a solder heat resistance temperature of 260 ° C. or more for 60 seconds or more. A metal foil laminated polyphenylene sulfide resin film obtained by laminating a metal foil on the polyphenylene sulfide resin film according to claim 1. The metal foil laminated polyphenylene sulfide resin film according to claim 8, wherein the metal foil is a copper foil. A multilayer laminate comprising a metal foil-laminated polyphenylene sulfide (PPS) resin film in which a plurality of metal foil-laminated polyphenylene sulfide resin films according to claim 8 or 9 are laminated.