WO2020213527A1 - Resin film, high-frequency circuit board, and production method for high-frequency circuit board - Google Patents

Abstract

Provided are: a resin film that can achieve improved thermal dimensional stability without a reduction in the low-dielectric properties and heat resistance characteristic of a film that is for use, for example, in a high-frequency circuit board produced from a poly(arylene ether ketone) resin; a high-frequency circuit board; and a production method for the high-frequency circuit board.　A resin film 1 that contains 100 parts by mass of a poly(arylene ether ketone) resin and 10–80 parts by mass of a non-swelling synthetic mica. The resin film 1 is molded using a molding material 4 that contains a non-swelling synthetic mica and can therefore achieve a reduced coefficient of linear expansion. As a result, the thermal dimensional stability of the resin film 1 is improved, it is possible to suppress differences in thermal dimensional properties relative to a metal layer that comprises a metal foil 2 or the like, and, when a conductive layer 3 is formed to produce a high-frequency circuit board, it is possible to prevent curling and deformation of the high-frequency circuit board.

Description

Resin film, high frequency circuit board and its manufacturing method

The present invention relates to a resin film used from the MHz band to the GHz band, a high-frequency circuit board and a method for manufacturing the same, and more particularly to a resin film used in the band from 800 MHz to 100 GHz or less, a high-frequency circuit board and a method for manufacturing the same. It is a thing.

In recent years, mobile information communication devices such as multifunctional mobile phones and tablet terminals, whose demand is rapidly expanding, and electronic devices such as next-generation televisions are required to send and receive larger amounts of data at high speed. Therefore, in response to this request, increasing the frequency of electric signals is being studied. For example, in the field of mobile information and communication, the fifth generation mobile communication system (5G) is being studied worldwide (see Patent Documents 1 and 2). The communication speed of this 5th generation mobile communication system is several tens of times higher than that of the previous generation, and in order to realize this, a high frequency band of 10 GHz or more is being studied for electric signals. Further, in the field of automobiles, the use of signals in a high frequency band of 60 GHz or more called millimeter waves is being studied as an in-vehicle radar system.

Special Table 2017-502595 Special Fair 6-27002 Gazette

However, conventional circuit boards are mainly designed and developed on the premise of communication utilizing the low frequency band, and are not designed and developed on the premise of large capacity and high speed communication utilizing the high frequency band. The value of the rate is as high as about 4.3 of the normal type, and the dielectric loss tangent is also not as low as about 0.018. On the other hand, a circuit board for large-capacity and high-speed communication is required to have a material having low dielectric properties such as relative permittivity and dielectric loss tangent, and excellent properties such as heat resistance and mechanical strength.

Explaining this point in detail, the relative permittivity is a parameter indicating the degree of polarization in the dielectric, and the higher the value, the larger the propagation delay of the electric signal. Therefore, in order to increase the propagation speed of the electric signal and enable high-speed calculation, it is preferable that the relative permittivity is low. The dielectric loss tangent (also referred to as tan δ) is a parameter indicating the amount of electrical signal propagating in the dielectric that is converted into heat and lost. The lower the value, the smaller the signal loss and the electrical signal transmissibility. Is improved. Further, since the dielectric loss tangent increases as the frequency increases in the high frequency band, it is necessary to use a material whose value can be reduced in order to suppress the loss as much as possible.

From the above, circuit boards used in high frequency bands such as the MHz band to the GHz band are manufactured from materials having a lower relative permittivity and dielectric loss tangent than before in order to realize large capacity and high speed communication. Is strongly desired. Based on this point, materials with low relative permittivity and dielectric loss tangent have been enthusiastically studied, and as a result, polyarylene ether ketone (PAEK) resin, which is also called aromatic polyetherketone, has been proposed and attracted attention.

Polyarylene ether ketone resin is a thermoplastic crystalline resin having excellent electrical insulation properties, mechanical properties, heat resistance, chemical resistance, radiation resistance, hydrolysis resistance, low water absorption, recyclability, etc. In view of this excellent property, the polyarylene ether ketone resin has been proposed and used in a wide range of fields such as automobile field, energy field, semiconductor field, medical field, aerospace component and the like.

If a resin film is produced from this polyarylene ether ketone resin, the relative permittivity of the resin film in the frequency range of 800 MHz or more and 100 GHz or less is 3.5 or less, and the dielectric loss tangent is 0.007 or less, resulting in excellent low dielectric properties. Obtainable. Further, according to this resin film, it is possible to obtain excellent heat resistance that the resin film does not deform even if it is floated in a solder bath at 288 ° C. for 10 seconds.

However, although the resin film made of polyarylene ether ketone resin can obtain excellent low dielectric properties and heat resistance, it is inferior in heating dimensional stability. Therefore, when the conductive layers are laminated, the heating dimensional characteristics with the conductive layer are obtained. Is so different that a new big problem of curling or deforming the laminated body arises.

As a method for improving the heating dimension stability of a resin film made of polyarylene ether ketone resin, (1) a method of molding a resin film with a molding material containing polyarylene ether ketone resin, hexagonal boron nitride, and talc (Patent). (See Japanese Patent No. 5896822), (2) A method of biaxially stretching a resin film containing 90% by mass or more of polyetheretherketone (see Patent No. 5847522) has been proposed.

However, in the case of the method (1), since hexagonal boron nitride is inferior in uniform dispersibility, there is a new problem that the quality of mechanical properties and dielectric properties is not stable. Further, in the case of the method (2), when the metal layer is formed on the resin film, the resin film and the metal foil are bonded with an adhesive, or the metal layer is laminated on the resin film via the seed layer. Although it is possible to do so, in the heat fusion between the resin film and the metal foil, the biaxial stretching is removed due to the melting of the resin film, and the laminated body is curled or deformed after laminating.

The present invention has been made in view of the above, and is a resin capable of improving heating dimensional stability without deteriorating the low dielectric property and heat resistance of a film for high frequency circuit boards manufactured from a polyarylene ether ketone resin. It is an object of the present invention to provide a film, a high frequency circuit board, and a method for manufacturing the same.

As a result of diligent research, the present inventors have focused on a polyarylene ether ketone resin having the highest heat resistance and excellent low dielectric property among thermoplastic resin materials, and the present invention has been made using this polyarylene ether ketone resin. Was completed.

That is, in order to solve the above problems, the present invention is characterized by a resin film containing 100 parts by mass of a polyarylene ether ketone resin and 10 parts by mass or more and 80 parts by mass or less of a non-swelling synthetic mica. ..

The relative crystallinity of the resin film is preferably 80% or more.
Further, it is preferable that the coefficient of linear expansion of the resin film is 1 ppm / ° C. or higher and 50 ppm / ° C. or lower.
Further, the non-swelling synthetic mica may be at least one of phlogopite fluorine, tetrasilicon mica potassium, and potassium teniolite.
The average particle size of synthetic mica is preferably 0.5 μm or more and 50 μm or less.
Further, it is desirable that the aspect ratio of the synthetic mica is 5 or more and 100 or less.

Further, in order to solve the above problems, the present invention is characterized in that it is a high frequency circuit board having the resin film according to any one of claims 1 to 4.
The high-frequency circuit board may include a metal layer that is heat-sealed and laminated on a resin film.

Further, in the present invention, in order to solve the above problems, the method for manufacturing a high frequency circuit board according to claim 5 or 6 is used.
A molding material containing at least 100 parts by mass of polyarylene ether ketone resin and 10 parts by mass or more and 80 parts by mass or less of non-swelling synthetic mica is melt-kneaded, and this molding material is extruded into a resin film by a die of an extrusion molding machine. By molding and bringing this resin film into contact with a cooling roll to cool it, the relative crystallinity of the resin film is set to 80% or more, and the linear expansion coefficient of this resin film is set to 1 ppm / ° C or higher and 50 ppm / ° C or lower. It is characterized by doing.

Here, the resin film in the claims includes a resin sheet in addition to the resin film. This resin film is not particularly limited to transparent, opaque, translucent, non-stretched film, uniaxially stretched film, and biaxially stretched film. Examples of the non-swellable synthetic mica include non-swellable synthetic mica heat-treated at 600 ° C. or higher. The metal layer is laminated on one side of the resin film or on both sides, if necessary.

According to the present invention, since the resin film is molded from a non-swelling synthetic mica-containing molding material, the coefficient of linear expansion of the resin film can be reduced and the heating dimension stability of the resin film can be improved. Further, since the resin film is molded from a molding material containing a polyarylene ether ketone resin, the relative permittivity of the resin film in the frequency range of 800 MHz or more and 100 GHz or less is 3.5 or less, and the dielectric loss tangent is 0.006 or less. , The values of relative permittivity and dielectric loss tangent can be made lower than before.

According to the present invention, the polyarylene ether ketone resin has an effect that the heating dimensional stability can be improved without deteriorating the low dielectric property and heat resistance of the manufactured resin film for high frequency circuit boards and the like. ..

According to the invention of claim 2, since the relative crystallinity of the resin film is 80% or more, excellent solder heat resistance can be obtained. Further, if the relative crystallinity of the resin film is 80% or more, it can be expected to secure the heating dimensional stability that can be used as a high frequency circuit board.

According to the invention of claim 3, since the coefficient of linear expansion of the resin film is 1 ppm / ° C. or higher and 50 ppm / ° C. or lower, when the resin film and the conductive layer are laminated, curl or warpage occurs when the resin film and the conductive layer are laminated. Can be prevented from being likely to occur. Further, it is possible to eliminate the possibility that the resin film and the conductive layer are peeled off.

According to the invention of claim 4, since the synthetic mica is at least one of phlogopite fluorine, tetrasilicon mica potassium, and potassium teniolite, it is possible to obtain excellent heating dimension stability and heat resistance. Become.

According to the invention of claim 5, the polyarylene ether ketone resin has an effect that the heating dimensional stability can be improved without deteriorating the low dielectric property and heat resistance of the produced resin film for a high frequency circuit substrate. There is.

According to the invention of claim 6, since it is not necessary to bond the resin film of the high frequency circuit board and the metal layer with an adhesive, it is possible to prevent the high frequency circuit board from being adversely affected by the adhesive. Further, since the metal layer can be used as a conductive layer as it is, it is possible to reduce the manufacturing cost.

According to the invention of claim 7, since the resin film of the high-frequency circuit substrate is molded by the melt extrusion molding method, the thickness accuracy, productivity, and handleability of the resin film are improved, and the manufacturing equipment is simplified. Can be done.

It is sectional drawing which shows typically the embodiment of the resin film and the high frequency circuit board which concerns on this invention. It is an overall explanatory view which shows typically the embodiment of the resin film, the high frequency circuit board and the manufacturing method thereof which concerns on this invention. It is sectional drawing which shows typically the 2nd Embodiment of the resin film and the high frequency circuit board which concerns on this invention.

Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, the high frequency circuit substrate in the present embodiment is laminated on the resin film 1 and the resin film 1. It is a circuit board for the fifth generation mobile communication system (5G) provided with a conductive layer 3 in a laminated structure, and the resin film 1 is a polyarylene ether ketone resin which is a thermoplastic resin and a mica which is excellent in electrical insulation and the like. A non-swellable synthetic mica that is produced by the molding material 4 containing and and contributes to dimensional stability is selected as the mica.

The resin film 1 is extruded into a film having a thickness of 2 μm or more and 1000 μm or less by a molding method using a molding material 4 containing a polyarylene ether ketone (PAEK) resin. The molding material 4 is prepared by adding 10 parts by mass or more and 80 parts by mass or less of non-swelling synthetic mica to 100 parts by mass of the polyarylene ether ketone resin. In addition to the above resins, the molding material 4 contains an antioxidant, a light stabilizer, an ultraviolet absorber, a plasticizer, a lubricant, a flame retardant, an antistatic agent, a heat resistance improver, and an inorganic substance as long as the characteristics of the present invention are not impaired. Compounds, organic compounds and the like are selectively added.

The polyarylene ether ketone resin of the molding material 4 is a crystalline resin composed of an arylene group, an ether group, and a carbonyl group, and is, for example, Patent No. 5709878, Japanese Patent No. 5847522, or [Asahi Research Center Co., Ltd .: Examples include the resins described in Super Engineering Plastics / PEEK (above), which grow in advanced applications, and are excellent in low dielectric properties and heat resistance.

Specific examples of the polyarylene ether ketone resin include a polyetheretherketone (PEEK) resin having a chemical structural formula represented by the chemical formula (1) and a polyetherketone having a chemical structure represented by the chemical formula (2). PEK) resin, polyetherketoneketone (PEKK) resin having the chemical structure represented by the chemical formula (3), polyetheretherketoneketone (PEEKK) resin having the chemical structure of the chemical formula (4), or the chemical formula (5). Examples thereof include polyetherketone etherketoneketone (PEKEKK) resin having a chemical structure.

Among these polyetheretherketone resins, a polyetheretherketone resin and a polyetherketoneketone resin are preferable from the viewpoints of easy availability, cost, and moldability of the resin film 1. Specific examples of polyetheretherketone resins include product names manufactured by Victrex, Victrex Powerer series, Victorex Granules series, product names manufactured by Dycel Ebonic, Vestakeep series, and product names manufactured by Solvay Specialty Polymers: Ketaspire. The PEEK series can be mentioned. Further, as a specific example of the polyetherketoneketone resin, the product name: KEPSTAN series manufactured by Arkema Co., Ltd. corresponds.

The polyarylene ether ketone resin may be used alone or in combination of two or more. Further, the polyarylene ether ketone resin may be a copolymer having two or more chemical structures represented by the chemical formulas (1) to (5). The polyarylene ether ketone resin is usually used in a form suitable for molding such as powder, granules, and pellets. The method for producing the polyarylene ether ketone resin is not particularly limited, but for example, the production method described in the literature [Asahi Research Center Co., Ltd .: Super engineering plastic PEEK (above) growing for advanced applications] is used. can give.

The mica (also called mica) of the molding material 4 is a plate-like crystal belonging to the phyllosilicate mineral mica family, and is a mineral characterized by having a complete cleavage on the bottom surface. This mica is classified into two types, natural mica (white mica, biotite, phlogopite, etc.) produced in the natural world and synthetic mica artificially produced using talc as the main raw material, and is industrially excellent in electricity. Widely used as an insulating material.

Natural mica has a different composition and structure depending on its production area, and also contains a large amount of impurities, so it is not suitable for producing a resin film 1 for a high-frequency circuit board with stable quality. Further, since natural mica has a hydroxyl group [OH group], there is a problem in heat resistance. On the other hand, synthetic mica is artificially manufactured mica, which has a constant composition and structure and few impurities. Therefore, the resin film 1 for a high-quality high-frequency circuit board that is stable in terms of heating dimensional stability and the like. Suitable for manufacturing. In addition, synthetic mica is superior in heat resistance to natural mica because all the hydroxyl groups are substituted with fluorine [F group]. Therefore, the mica used in the present invention is preferably synthetic mica rather than natural mica.

Synthetic mica is classified into non-swelling mica and swelling mica according to the difference in behavior with respect to water. Non-swelling mica is a type of synthetic mica that does not change in dimensional stability or the like even when it comes into contact with water. On the other hand, swelling mica is a synthetic mica having a property of absorbing moisture in the air, swelling, and cleaving. When swellable mica is used, since the swellable mica contains water, the resin film 1 for the high frequency circuit board may foam during molding. Therefore, the synthetic mica that can be used in the present invention is preferably non-swellable mica that is excellent in heat dimensional stability and water resistance, and more preferably synthetic mica that has been heat-treated at 600 ° C. or higher.

The non-swelling synthetic mica is not particularly limited, but the synthetic mica represented by the following general formula is preferably used.
General formula: X _{1/3 to 1.0} Y _{2 to 3} (Z ₄ O ₁₀ ) F _{1.5 to 2.0}

Here, X is a cation that forms an interlayer with a coordination number of 12, Y is a cation that forms an octahedral seat with a coordination number of 6, and Z is a cation that forms a tetrahedron with a coordination number of 4. Substituted by one or more ions [X: Na ⁺ , K ⁺ , Li ⁺ , Rb ⁺ , Ca ²⁺ , Ba ²⁺ and Sr ²⁺ , Y: Mg ²⁺ , Fe ²⁺ , Ni ²⁺ , Mn ²⁺ , Co ²⁺ , Zn ²⁺ , Ti ²⁺ , Al ³⁺ , Cr ³⁺ , Fe ³⁺ , Li ⁺ , Z: Al ³⁺ , Fe ³⁺ , Si ⁴⁺ , Ge ⁴⁺ , B ³⁺ ].

Examples of non-swelling synthetic mica include phlogopite fluorine (KMg ₃ (AlSi ₃ O ₁₀ ) F ₂ ), potassium tetrasilicon mica (KMg _2.5 (Si ₄ O ₁₀ ) F ₂ ), and potassium teniolite (KMg). ₂ Li (Si ₄ O ₁₀ ) F ₂ ) can be mentioned. Of these, non-swelling phlogopite fluorine is the most suitable. Specific examples of this synthetic mica include potassium tetrasilicon mica manufactured by Katakura Corp. Agri, which is a high-purity, fine powder with excellent heat resistance [product name: Micromica MK series], and phlogopite fluorine mica manufactured by Topy Industries, Ltd. [PDM series. ], Potassium tetrasilicon mica manufactured by Topy Industries, Ltd. [PDM series] and the like.

Examples of the method for producing synthetic mica include (1) melting method, (2) solid phase reaction method, and (3) intercalation method. In the melting method (1), raw materials such as silica, magnesium oxide, alumina, fluoride, valerite, kalan rock, and oxides and carbon salts of various metals are combined and mixed, and melted at a high temperature of 1300 ° C. or higher. The solid-state reaction method (2) uses talc as the main raw material, and oxides and carbonates of various metals including alkali fluoride, alkali silicate, and transition metals are added to the talc. In addition, the manufacturing method of mixing and reacting at around 1000 ° C., the intercalation method of (3), is a manufacturing method of manufacturing by an intercalation method using talc as a main raw material.

The average particle size of synthetic mica is 0.5 μm or more and 50 μm or less, preferably 1 μm or less and 30 μm or less, more preferably 2 μm or more and 20 μm or less, and further preferably 3 μm or more and 10 μm or less. This is because when the average particle size of the synthetic mica is 0.5 μm or less, the synthetic mica particles are likely to aggregate and the uniform dispersibility in the polyarylene ether ketone resin is lowered.

On the other hand, when the average particle size of the synthetic mica exceeds 50 μm, the toughness of the resin film 1 for the high frequency circuit substrate obtained from the mixture of the polyarylene ether ketone resin and the synthetic mica may decrease. .. Further, when the average particle size of the synthetic mica exceeds 50 μm, the synthetic mica protrudes from the surface of the resin film 1, and the surface of the resin film 1 becomes rough, which hinders the transmission characteristics.

The aspect ratio of synthetic mica should be 5 or more and 100 or less. Here, the aspect ratio means a value obtained by dividing the diameter of the particles by the thickness when the synthetic mica is a scaly powder. The specific aspect ratio of the synthetic mica is 5 or more and 100 or less, preferably 10 or more and 90 or less, more preferably 20 or more and 80 or less, and further preferably 30 or more and 50 or less.

This is because when the aspect ratio is less than 5, the effect of improving the heating dimensional stability is low, and the mechanical properties in the extrusion direction and the width direction of the resin film 1 and the anisotropy of the heating dimensional stability are large. This is because it is inappropriate. On the other hand, when the aspect ratio exceeds 100, the toughness of the resin film 1 obtained from the mixture of the polyarylene ether ketone resin and synthetic mica decreases.

Synthetic mica is added in the range of 10 parts by mass or more and 80 parts by mass or less, preferably 20 parts by mass or more and 70 parts by mass or less, and more preferably 30 parts by mass or more and 60 parts by mass or less with respect to 100 parts by mass of the polyarylene ether ketone resin. Will be done. This is because when the amount of synthetic mica added is less than 10 parts by mass, the effect of adjusting the heating dimensional stability of the resin film 1 for the high-frequency circuit board becomes insufficient.

On the other hand, if the amount of synthetic mica added exceeds 80 parts by mass, the polyarylene ether ketone resin may be thermally decomposed due to significant heat generation during the preparation of the molding material 4 composed of the polyarylene ether ketone resin and the synthetic mica. Because there is. Further, the toughness of the resin film 1 obtained from the molding material 4 is lost and the resin film 1 becomes extremely brittle, and the resin film 1 may be damaged during molding. Furthermore, it is based on the reason that the relative permittivity and the dielectric loss tangent increase significantly more than necessary because the amount of synthetic mica added is large.

Synthetic mica is a silane coupling agent [vinyltrimethoxysilane, vinyltriethoxysilane, 2- (3,4-epylcyclohexyl) ethyltrimethoxy, as long as the characteristics of the resin film 1 for a high-frequency circuit substrate are not impaired. Silane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyl Triethoxysilane, p-stiltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3 -Achroxypropyltrimethoxysilane, N-2 (aminoethyl) -3-aminopropylmethyldimethoxylane, N-2 (aminoethyl) -3-aminopropyltrimethoxylan, 3-aminopropyltrimethoxysilane, 3 -Aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl Hydrochloride of -3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-isocyanuppropyltriethoxysilane, tris- (trimethoxysilylpropyl) isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercapto Propyltrimethoxysilane, etc.], Silane agent [Methyltrimethoxysilane, dimethyldimethoxysilane, phenylsilane, dimethoxydiphenylsilane, n-propyltrimethoxysilane, hexyltrimethoxysilane, decyltrimethoxysilane, 1,6-bis (tri) Methoxysilylsilane) hexane, trifluoropropylmethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyltriethoxysilane, phenyltriethoxysilane, n-propyltriethoxysilane, hexyltriethoxysilane, octyltriethoxysilane, hexamethyl Disilazan, imidazole silane, etc.], titanate-based coupling agent [isopropyltriisostearoyl titanate, isopropyltris (dioctyl pie) Lophosphate) titanate, isopropyltri (N-aminoethyl-aminoethyl) titanate, tetraoctylbis (ditridecylphosphite) titanate, tetra (2,2-dialyloxy-1-butyl) bis (ditrydecyl) phosphite titanate , Bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) oxyacetate titanate, isopropyltrioctanoyl titanate, isopropyldimethacrylisostearoyl titanate, isopropyltridodecylbenzenesulfonyl titanate, isopropylisostearoyldiacrylic titanate, isopropyltri (Dioctylphosphate) titanate, isopropyltricylphenyl titanate, tetraisopropylbis (dioctylphosphate) titanate, etc.], aluminate-based coupling agent [acetoalkoxyaluminum diisopropirate, etc.], etc. be able to.

The polyarylene ether ketone resin and synthetic mica are melt-kneaded for a predetermined time to form a molding material 4 for the resin film 1. As a method for preparing the molding material 4, (1) polyarylene ether ketone resin and fine A method in which synthetic mica is added to molten polyarylene ether ketone without stirring and mixing with powdered synthetic mica, and these are melt-kneaded to prepare a molding material 4. (2) Polyarylene ether ketone resin and fine Examples thereof include a method of preparing the molding material 4 by stirring and mixing the powdered synthetic mica with the synthetic mica at room temperature (temperature of about 0 ° C. or higher and 50 ° C. or lower) and then melt-kneading. Any of these methods (1) and (2) may be used, but the method (1) is preferable from the viewpoint of dispersibility and workability.

To specifically explain the method (1), in order to prepare the molding material 4, first, a polyarylene ether ketone resin is mixed with a mixing roll, a pressure kneader, a Banbury mixer single-screw extruder, and a multi-screw extruder (biaxial). The molding material 4 is prepared by melting with a melt-kneader such as an extruder, a triaxial extruder, a 4-screw extruder, etc., and adding synthetic mica to a polyarylene ether ketone resin to melt-knead and disperse the resin.

The temperature at the time of preparation of the melt-kneader is not particularly limited as long as it can be melt-kneaded and dispersed and the polyarylene ether ketone resin does not decompose, but is in the range of the melting point of the polyarylene ether ketone resin and lower than the thermal decomposition temperature. .. Specifically, the range is preferably 320 ° C. or higher and 450 ° C. or lower, preferably 360 ° C. or higher and 420 ° C. or lower, and more preferably 380 ° C. or higher and 400 ° C. or lower.

This is because if the temperature is lower than the melting point of the polyarylene ether ketone resin, the polyarylene ether ketone resin does not melt, so that the molding material 4 containing the polyarylene ether ketone resin cannot be melt-extruded, and conversely, thermal decomposition occurs. This is based on the reason that the polyarylene ether ketone resin may be violently decomposed when the temperature is exceeded. The prepared molding material 4 is usually extruded into a lump, a strand, a sheet, or a rod, and then used in a crusher or a cutting machine in a form suitable for molding such as a lump, a granule, or a pellet. ..

Next, the method (2) will be specifically described. In order to obtain a stirring mixture by stirring and mixing the polyarylene ether ketone resin and synthetic mica, a tumbler mixer, a hensyl mixer, a V-type mixer, and a nouter mixer , Ribbon blender, universal stirring mixer, etc. At this time, the shape of the polyarylene ether ketone resin is preferably in the form of a powder that can be more uniformly dispersed with synthetic mica. Examples of the method of crushing into powder include a shear crushing method, an impact crushing method, a collision crushing method, a frozen crushing method, and a solution crushing method.

The molding material 4 is a mixing roll of a stirred mixture of polyarylene ether ketone resin and synthetic mica, a pressure kneader, a Banbury mixer, a single-screw extruder, and a multi-screw extruder (two-screw extruder, three-screw extruder, four-screw extruder). It is prepared by melt-kneading and dispersing with a melt-kneader such as a machine).

The temperature of the melt-kneader at the time of this preparation is not particularly limited as long as it can be melt-kneaded and dispersed and the polyarylene ether ketone resin does not decompose, but is in the range of the melting point of the polyarylene ether ketone resin and lower than the thermal decomposition temperature. Is. Specifically, for the same reason as in the method (1), the range is preferably 320 ° C. or higher and 450 ° C. or lower, preferably 360 ° C. or higher and 420 ° C. or lower, and more preferably 380 ° C. or higher and 400 ° C. or lower. The prepared molding material 4 is usually extruded into a lump, a strand, a sheet, or a rod, and then used in a crusher or a cutting machine in a form suitable for molding such as a lump, a granule, or a pellet. ..

The molding material 4 is molded into the resin film 1 by various molding methods such as a melt extrusion molding method, a calender molding method, and a casting molding method. Among these molding methods, the melt extrusion molding method is most suitable from the viewpoint of improving handleability and simplifying equipment. In this melt extrusion molding method, as shown in FIG. 2, the molding material 4 is melt-kneaded by a melt extrusion molding machine 10 such as a single-screw extruder or a twin-screw extrusion machine, and the T-die 13 of the melt extrusion molding machine 10 is used. This is a method of continuously extruding a strip-shaped resin film 1 in the directions of a plurality of cooling rolls 16 and crimping rolls 17.

As shown in FIG. 2, the melt extrusion molding machine 10 includes, for example, a single-screw extrusion molding machine, a twin-screw extrusion molding machine, and the like, and functions to melt-knead the charged molding material 4. A raw material input port 11 for the polyarylene ether ketone resin of the molding material 4 is installed behind the upper part on the upstream side of the melt extrusion molding machine 10, and helium gas, neon gas, argon gas, etc. are installed in the raw material input port 11. An inert gas supply pipe 12 that supplies an inert gas such as krypton gas, nitrogen gas, or carbon dioxide gas as needed is connected, and the inflow of the inert gas through the inert gas supply pipe 12 causes a molding material. Oxidation deterioration and oxygen cross-linking of the polyarylene ether ketone resin of No. 4 are effectively prevented.

The temperature of the melt extrusion molding machine 10 is not particularly limited as long as the resin film 1 can be molded and the polyarylene ether ketone resin does not decompose, but the thermal decomposition temperature is equal to or higher than the melting point of the polyarylene ether ketone resin. The range less than is good. Specifically, the temperature is adjusted to 320 ° C. or higher and 450 ° C. or lower, preferably 360 ° C. or higher and 420 ° C. or lower, and more preferably 380 ° C. or higher and 400 ° C. or lower. This is because when the temperature of the melt extrusion molding machine 10 is lower than the melting point of the polyarylene ether ketone resin, the polyarylene ether ketone resin does not melt and molding of the resin film 1 becomes difficult, and conversely, the temperature is equal to or higher than the thermal decomposition temperature. In this case, the polyarylene ether ketone resin is violently decomposed.

The T die 13 is attached to the tip of the melt extrusion molding machine 10 via a connecting pipe 14 and functions to continuously push the strip-shaped resin film 1 downward. The temperature at the time of extrusion of the T-die 13 is in the range of the melting point of the polyarylene ether ketone resin or more and less than the thermal decomposition temperature. Specifically, the temperature is adjusted to 320 ° C. or higher and 450 ° C. or lower, preferably 360 ° C. or higher and 420 ° C. or lower, and more preferably 380 ° C. or higher and 400 ° C. or lower. This hinders melt extrusion molding of the molding material 4 containing the polyarylene ether ketone resin when it is lower than the melting point of the polyarylene ether ketone resin, and conversely, when it exceeds the thermal decomposition temperature, the polyarylene ether It is based on the reason that the ketone resin may be severely decomposed.

It is preferable that the gear pump 15 is mounted on the connecting pipe 14 upstream of the T die 13. The gear pump 15 transfers the molding material 4 melt-kneaded by the melt extrusion molding machine 10 to the T-die 13 at a constant flow rate and with high accuracy.

The plurality of cooling rolls 16 are made of a rotatable metal roll having a diameter larger than that of the crimping roll 17, for example, and are arranged and axially supported in a row from below the T-die 13 in the downstream direction, and the extruded resin film 1 is provided. It is sandwiched between the adjacent cooling rolls 17 and between the adjacent cooling rolls 16 and the cooling rolls 16, and the thickness of the resin film 1 is kept within a predetermined range while cooling the resin film 1 together with the crimping rolls 17. To control.

Each cooling roll 16 has a polyarylene ether ketone resin [glass transition point + 20 ° C.] or more and less than the melting point of the polyarylene ether ketone resin, preferably a polyarylene ether ketone resin [glass transition point + 30 ° C.] or more. [Glass transition point + 160 ° C] or less, more preferably [Glass transition point + 50 ° C] or more of polyarylene ether ketone resin or more, [Glass transition point + 140 ° C] or less of polyarylene ether ketone resin, still more preferably polyarylene ether ketone resin. It is adjusted to the temperature range of [Glass transition point + 60 ° C.] or more of the polyarylene ether ketone resin [Glass transition point + 120 ° C.], and is in sliding contact with the resin film 1 for a high frequency circuit substrate.

Explaining this point, when the temperature of each cooling roll 16 is less than the [glass transition point + 20 ° C.] of the polyarylene ether ketone resin, the relative crystallinity of the resin film 1 is less than 80%, and the solder heat resistance is improved. There is a problem that it cannot be obtained. On the other hand, when the temperature of each cooling roll 16 is equal to or higher than the melting point of the polyarylene ether ketone resin, the resin film 1 may stick to the cooling roll 16 and break during the production of the resin film 1. Examples of the temperature adjustment and cooling method of each cooling roll 16 include a method using a heat medium such as air, water, and oil, an electric heater, induction heating, and the like.

A pair of the plurality of pressure-bonding rolls 17 are rotatably supported from below the T-die 13 of the melt extrusion molding machine 10 in the downstream direction, sandwiching the plurality of cooling rolls 16 arranged in a row, and forming a resin film on the cooling rolls 16. 1 is pressed. In the pair of crimping rolls 17, a winding machine 18 for the resin film 1 is installed downstream of the crimping roll 17 located on the downstream side, and a resin is placed between the pair of crimping rolls 17 and the winding pipe 19 of the winding machine 18. A slit blade 20 that forms a slit on the side of the film 1 is arranged so as to be able to move up and down at least, and a tension is applied to the resin film 1 between the slit blade 20 and the winder 18 to smoothly wind the resin film 1. The required number of shafts of tension rolls 21 for taking are rotatably supported.

In order to improve the adhesion between the resin film 1 and the cooling roll 16 on the peripheral surface of each pressure-bonding roll 17, at least natural rubber, isoprene rubber, butadiene rubber, norbornene rubber, acrylonitrile butadiene rubber, nitrile rubber, urethane rubber, and silicone A rubber layer such as rubber or fluororubber is formed by coating as needed, and an inorganic compound such as silica or alumina is selectively added to this rubber layer. Among these, it is preferable to use silicone rubber or fluororubber having excellent heat resistance.

As the pressure-bonding roll 17, a metal elastic roll having a metal surface is used as needed, and when this metal elastic roll is used, it is possible to form a polyarylene ether ketone resin film 1 having an excellent surface smoothness. Become. Specific examples of this metal elastic roll include a metal sleeve roll, an air roll [manufactured by Dimco: product name], a UF roll [manufactured by Hitachi Zosen Corporation: product name], and the like.

Like the cooling roll 16, such a pressure-bonding roll 17 has a polyarylene ether ketone resin [glass transition point + 20 ° C.] or more and less than the melting point of the polyarylene ether ketone resin, preferably a polyarylene ether ketone resin [glass transition point +30]. ° C] or higher, polyarylene ether ketone resin [glass transition point + 160 ° C] or lower, more preferably polyarylene ether ketone resin [glass transition point + 50 ° C] or higher, polyarylene ether ketone resin [glass transition point + 140 ° C] or lower, More preferably, it is adjusted to a temperature range of [glass transition point + 60 ° C.] or higher of the polyarylene ether ketone resin [glass transition point + 120 ° C.] of the polyarylene ether ketone resin, and is in sliding contact with the resin film 1.

The temperature of the crimping roll 17 is adjusted to the relevant temperature range in order to adjust the relative crystallization of the resin film 1 to 80% or more. That is, when the temperature of the pressure-bonding roll 17 is less than the [glass transition point + 20 ° C.] of the polyarylene ether ketone resin film 1, the relative crystallinity of the polyarylene ether ketone resin film 1 is less than 80%, and the solder heat resistance. The problem arises that Further, when the temperature of the pressure-bonding roll 17 is equal to or higher than the melting point of the polyarylene ether ketone resin, the resin film 1 may stick to the cooling roll 16 during the production of the resin film 1 and may break.

As with the cooling roll 16, the temperature adjustment and cooling method of each crimping roll 17 is not limited, and examples thereof include a method using a heat medium such as air, water, and oil, an electric heater, and dielectric heating.

In the above, when manufacturing the resin film 1 for a high-frequency circuit board, as shown in FIG. 2, first, the molding material 4 is inactive at the raw material input port 11 of the melt extrusion molding machine 10 as shown by an arrow in the figure. The gas is charged while being supplied, and the polyarylene ether ketone resin of the molding material 4 and the synthetic mica are melt-kneaded by the melt extrusion molding machine 10, and the resin film 1 is continuously extruded from the T die 13 into a strip shape.

At this time, the water content of the molding material 4 before melt extrusion is adjusted to 2000 ppm or less, preferably 1000 ppm or less, and more preferably 100 ppm or more and 500 ppm or less. This is because when the water content exceeds 2000 ppm, the polyarylene ether ketone resin may foam immediately after being extruded from the T die 13.

After extruding the resin film 1, the resin film 1 is sequentially wound on a pair of crimping rolls 17, a plurality of cooling rolls 16, a tension roll 21, and a winding pipe 19 of a winding machine 18, and then the resin film 1 is cooled by the cooling roll 16. If both sides of the resin film 1 are cut by the slit blades 20 and the resin film 1 is sequentially wound around the winding tube 19 of the winding machine 18, the resin film 1 for a high-frequency circuit board can be manufactured. During the production of the resin film 1, fine irregularities can be formed on the surface of the resin film 1 without losing the effect of the present invention, and the friction coefficient of the surface of the resin film 1 can be reduced.

The thickness of the resin film 1 is not particularly limited as long as it is 2 μm or more and 1000 μm or less, but is preferably 10 μm or more and 800 μm from the viewpoint of ensuring a sufficient thickness of the high-frequency circuit board, handling, and thinning. Below, it is more preferably 20 μm or more and 500 μm or less, and further preferably 75 μm or more and 250 μm or less.

The relative permittivity of the resin film 1 in the frequency range of 800 MHz or more and 100 GHz or less, preferably 1 GHz or more and 90 GHz or less, more preferably 10 GHz or more and 85 GHz or less, and further preferably 25 GHz or more and 80 GHz or less, realizes high-speed communication utilizing a high frequency band. From the viewpoint of the above, 3.5 or less, preferably 3.3 or less, more preferably 3.1 or less, still more preferably 3.0 or less is preferable. The lower limit of the relative permittivity is not particularly limited, but is practically 1.5 or more.

Specifically, the relative permittivity of the resin film 1 at a frequency of 1 GHz is 3.4 or less, the relative permittivity at a frequency of 10 GHz is 3.17 or less, the relative permittivity near a frequency of 28 GHz is 3.29 or less, and the frequency is 76.5 GHz. The relative permittivity in is preferably 3.42 or less. This is because if the relative permittivity of the resin film 1 in the frequency range of 800 MHz or more and 100 GHz or less exceeds 3.5, the propagation speed of the electric signal decreases, which causes a problem that it is not suitable for high-speed communication.

The dielectric loss tangent in the frequency range of 800 MHz or more and 100 GHz or less, preferably 1 GHz or more and 90 GHz or less, more preferably 10 GHz or more and 85 GHz or less, and further preferably 25 GHz or more and 80 GHz or less of the resin film 1 realizes high-speed communication utilizing a high frequency band. Therefore, 0.007 or less, preferably 0.005 or less, more preferably 0.004 or less, still more preferably 0.003 or less is preferable. The lower limit of the dielectric loss tangent is not particularly limited, but is 0.0001 or more in practical use.

Specifically, it is desirable that the dielectric loss tangent of the resin film 1 at a frequency of 1 GHz is 0.003 or less, and the dielectric loss tangent at a frequency of around 10 GHz is 0.003 or less. Further, the dielectric loss tangent near the frequency of 28 GHz is preferably 0.0037 or less, and the dielectric loss tangent near the frequency of 76.5 GHz is preferably 0.0050 or less. These are based on the reason that when the dielectric loss tangent in the frequency range of 800 MHz or more and 100 GHz or less exceeds 0.007, the loss is large and the signal transduction rate is lowered, which is not suitable for large-capacity communication.

The method for measuring the specific dielectric constant and the dielectric tangent is not particularly limited, but is reflected / transmitted (S) such as the coaxial probe method, the coaxial S parameter method, the waveguide S parameter method, and the free space S parameter method. Parameter) method, measurement method using strip line (ring) resonator, cavity resonator perturbation method, measurement method using split-post waveguide resonator, measurement method using cylindrical (split cylinder) cavity resonator, Measurement methods using a multi-frequency balanced disc resonator, measurement methods using a cut-off cylindrical waveguide cavity resonator, resonator methods such as an open resonator method using a fabric perot resonator, etc. Be done.

In addition, the Fabry-Perot method using an open interferometer, the method of obtaining the relative permittivity and dielectric loss tangent of high frequencies by the cavity resonator perturbation method, the three-terminal measurement method by a mutual induction bridge circuit, etc. can be mentioned. Of these, the Fabry-Perot method and the cavity resonator perturbation method, which are excellent in high resolution, are the most suitable.

The relative crystallinity of the resin film 1 is 80% or more, preferably 90% or more, more preferably 95% or more, still more preferably 100%. This is because when the relative crystallinity of the resin film 1 is less than 80%, there is a problem in the solder heat resistance of the resin film 1. Further, when the relative crystallinity is 80% or more, it can be expected to secure the heating dimensional stability that can be used as a high frequency circuit board.

The crystallinity of the resin film 1 can be expressed by the relative crystallinity. The relative crystallinity of the resin film 1 is calculated by the following formula based on the thermal analysis result measured at a heating rate of 10 ° C./min using a differential scanning calorimeter.

Relative crystallinity (%) = {1- (ΔHc / ΔHm)} × 100
ΔHc: calorific value of recrystallization peak (J / g)
ΔHm: Calorific value of melting peak (J / g)

The thermal dimensional stability of the resin film 1 can be expressed by the coefficient of linear expansion. The coefficient of linear expansion is 1 ppm / ° C. or higher and 50 ppm / ° C. or lower, preferably 3 ppm / ° C. or higher and 40 ppm / ° C. or lower, and more preferably 5 ppm / ° C. or higher in both the extrusion direction and the width direction (direction perpendicular to the extrusion direction) of the resin film 1. It is preferably 35 ppm / ° C. or lower, more preferably 10 ppm / ° C. or higher and 30 ppm / ° C. or lower. This is because if the coefficient of linear expansion deviates from the range of 1 ppm / ° C. or higher and 50 ppm / ° C. or lower, curling or warpage is likely to occur when the resin film 1 and the conductive layer 3 are laminated, and the resin film 1 and the conductive layer 3 This is because there is a risk of peeling.

The mechanical properties of the resin film 1 can be evaluated by the tensile elastic modulus at 23 ° C. The tensile elastic modulus of the resin film 1 at 23 ° C. is 3500 N / mm ² or more and 10000 N / mm ² or less, preferably 3800 N / mm ² or more and 9000 N / mm ² or less, more preferably 3900 N / mm ² or more and 8880 N / mm ² or less. The range is optimal. This is because when the tensile elastic modulus is less than 3500 N / mm ² , the resin film 1 is inferior in rigidity, so that the resin film 1 may be wrinkled or the resin film 1 may be deformed during the production of the high frequency circuit substrate. Because there is. On the contrary, when it exceeds 10000 N / mm ² , it takes a long time to mold the resin film 1, and the cost reduction cannot be expected.

The heat resistance of the resin film 1 is preferably evaluated by the solder heat resistance in consideration of the convenience of manufacturing a high frequency circuit board. Specifically, in accordance with the JIS standard C 5016 test method, the resin film 1 is floated in a solder bath at 288 ° C for 10 seconds, and if the resin film 1 is found to be deformed or wrinkled, it becomes heat resistant. If it is evaluated that there is a problem and no deformation or wrinkles are observed in the resin film 1, it is evaluated that there is no problem in heat resistance.

Next, in the case of manufacturing a high-frequency circuit board, if the conductive layer 3 is formed on the manufactured resin film 1 and then the wiring pattern of the conductive circuit is formed on the conductive layer 3, the high-frequency circuit board can be manufactured. Can be done. The conductive layer 3 is formed on either the front and back surfaces, the front surface, or the back surface of the resin film 1, and the wiring pattern of the conductive circuit is formed later. Examples of the conductor used for the conductive layer 3 include metals such as copper, gold, silver, chromium, iron, aluminum, nickel and tin, or alloys made of these metals.

The conductive layer 3 is formed by (1) heat-sealing the resin film 1 and the metal foil 2 to form the conductive layer 3, and (2) bonding the resin film 1 and the metal foil 2 with an adhesive. (3) A seed layer is formed on the resin film 1 and a metal layer is laminated on the seed layer, and the conductive layer 3 is formed from the seed layer and the metal layer. The method of forming the above is mentioned.

The method (1) is a method in which a resin film 1 and a metal foil 2 are sandwiched between a press molding machine or a roll and heated and pressurized to form a conductive layer 3. In the case of this method, the thickness of the metal foil 2 is preferably in the range of 1 μm or more and 100 μm or less, preferably 5 μm or more and 80 μm or less, and more preferably 10 μm or more and 70 μm or less.

The surface of the resin film 1 or the metal foil 2 can form fine irregularities in order to improve the fusion strength at the time of heat fusion. Further, the surface of the resin film 1 or the metal foil 2 may be surface-treated by corona irradiation treatment, ultraviolet irradiation treatment, plasma irradiation treatment, frame irradiation treatment, itro irradiation treatment, oxidation treatment, hairline processing, sand mat processing or the like. Further, the surface of the resin film 1 or the metal foil 2 can be treated with a silane coupling agent, a silane agent, a titaniumate-based coupling agent, or an aluminate-based coupling agent.

In the method (2), an adhesive such as an epoxy resin adhesive, a phenol resin adhesive, or a siloxane-modified polyamide imide resin adhesive is placed between the resin film 1 and the metal foil 2, and a press molding machine or a roll is used. This is a method of forming a metal foil 2 on a resin film 1 by sandwiching it between them and then heating and pressurizing it. In the case of this method, the thickness of the metal foil 2 is preferably in the range of 1 μm or more and 100 μm or less, preferably 5 μm or more and 80 μm or less, and more preferably 10 μm or more and 70 μm or less.

Similar to the above, the surface of the resin film 1 or the metal foil 2 can be formed with fine irregularities from the viewpoint of improving the adhesive strength. Further, the surface of the resin film 1 or the metal foil 2 may be surface-treated by corona irradiation treatment, ultraviolet irradiation treatment, plasma irradiation treatment, frame irradiation treatment, itro irradiation treatment, oxidation treatment, hairline processing, sand mat processing, or the like. Absent. Further, the surface of the resin film 1 or the metal foil 2 can be treated with a silane coupling agent, a silane agent, a titaniumate-based coupling agent, or an aluminate-based coupling agent in the same manner as described above.

In the method (3), a seed layer for adhesion is formed on the resin film 1 by a method such as a sputtering method, a thin film deposition method, or a plating method, and a heat fusion method, a thin film deposition method, or a plating method is used on the seed layer. This is a method of forming a metal layer and forming the seed layer and the metal layer on the conductive layer 3. As the seed layer, for example, a metal such as copper, gold, silver, chromium, iron, aluminum, nickel, tin, zinc, or an alloy composed of these metals can be used. The thickness of the seed layer is usually in the range of 0.1 μm or more and 2 μm or less.

When forming a seed layer on the resin film 1, it is possible to form an anchor layer for the purpose of improving the adhesive strength of these layers. Examples of the anchor layer include metals such as nickel and chromium, but nickel having excellent environmental friendliness is preferably preferable.

As the metal layer, for example, a metal such as copper, gold, silver, chromium, iron, aluminum, nickel, tin, zinc or an alloy composed of these metals can be used. The metal layer may be a single layer made of one kind of metal, or may be a plurality of layers or multiple layers made of two or more kinds of metals. The thickness of the metal layer is not particularly limited, but is preferably 0.1 μm or more and 50 μm or less, preferably 1 μm or more and 30 μm or less.

The conductive layer 3 composed of the seed layer and the metal layer is preferably in the range of 0.2 μm or more and 50 μm or less, preferably 1 μm or more and 30 μm or less, more preferably 5 μm or more and 20 μm or less, and further preferably 5 μm or more and 10 μm or less. The seed layer and the metal layer may be the same metal or different metals. Further, in order to prevent surface corrosion, a metal protective layer such as gold or nickel may be coated on the surface of the metal layer.

Among these methods for forming the conductive layer 3, the method (1) in which the resin film 1 and the metal foil 2 are heat-sealed is the most suitable. This is because in the case of the method (2), it is necessary to bond the resin film 1 and the metal foil 2 with an adhesive, so that the dielectric properties of the adhesive are reflected, and the relative permittivity and dielectric constant of the high frequency circuit board are reflected. This is because there is a situation in which the direct contact rises. Further, in the case of the method (3), the process of forming the conductive layer 3 becomes complicated, which leads to an increase in cost.

The required number of wiring patterns for the conductive circuit can be formed by an etching method, a plating method, a printing method, or the like. As a method for forming this wiring pattern, it is possible to use a sulfuric acid-hydrogen peroxide system, an etching agent for iron chloride, or the like, which minimizes the occurrence of undercut and wiring thinning and enables good wiring formation. By forming such a wiring pattern having a predetermined shape, it is possible to manufacture a high-frequency circuit board having excellent low dielectric properties and capable of suppressing signal loss.

According to the above, since the resin film 1 is molded by the molding material 4 containing non-swellable synthetic mica, the coefficient of linear expansion can be reduced. Therefore, when the heating dimensional stability of the resin film 1 can be improved, the difference in the heating dimensional characteristics from the metal layer made of the metal foil 2 or the like can be suppressed, and the conductive layer 3 is laminated to manufacture the high frequency circuit board. In addition, it is possible to prevent the high frequency circuit board from being curled or deformed.

Further, since the resin film 1 is molded by the molding material 4 containing the polyarylene ether ketone resin, the relative permittivity of the resin film 1 in the frequency range of 800 MHz or more and 100 GHz or less is 3.5 or less, and the dielectric loss tangent is 0. It becomes 007 or less, and the values of the relative permittivity and the dielectric loss tangent can be made lower than before. Therefore, it is possible to obtain a high-frequency circuit board capable of transmitting and receiving a large-capacity high-frequency signal at high speed. Further, the use of this high frequency circuit board makes it possible to greatly contribute to the realization of the fifth generation mobile communication system.

Further, since the polyarylene ether ketone resin is used, the loss is reduced, and the resin film 1 for the high frequency circuit board can be used for a long period of time, which makes it very easy to realize high-speed communication utilizing the high frequency band. .. Further, since the polyarylene ether ketone resin is used instead of the polyimide resin, it is possible to easily multi-layer the high frequency circuit board. Further, since the resin film 1 having a relative crystallinity of 80% or more, which is excellent in heat resistance, is used as the substrate material, excellent solder heat resistance can be obtained.

Next, FIG. 3 shows a second embodiment of the present invention. In this case, metal foils 2 for wiring patterns are laminated on both the front and back surfaces of the resin film 1 by a heat fusion method, and the pair is laminated. The conductive layer 3 is formed by the metal foil 2 of the above. Since the other parts are the same as those in the above embodiment, the description thereof will be omitted.

In this embodiment as well, the same effects as those in the above embodiment can be expected, and since the conductive layers 3 are formed on both sides of the resin film 1, the wiring of the high frequency circuit board is made denser and the high frequency circuit board is made into multiple layers. Clearly makes it easier.

Although one type of synthetic mica was used alone in the above embodiment, two or more types may be used in combination. Further, although the conductive layer 3 is laminated on one resin film 1, the present invention is not limited to this, and the conductive layer 3 may be newly laminated on a plurality of resin films 1 having a laminated structure. Further, the metal foil 2 is laminated on the surface of the resin film 1 by a heat fusion method, and the conductive layer 3 is laminated and formed. However, the present invention is not limited to this, and the metal foil 2 may be laminated and formed by a vapor deposition method or a plating method. good. Further, the high frequency circuit board can also be used for an automobile collision prevention millimeter wave radar device, an advanced driver assistance system (ADAS), artificial intelligence (AI), and the like.

Hereinafter, examples of the resin film, the high-frequency circuit board, and the method for manufacturing the same according to the present invention will be described together with comparative examples.
[Example 1]
First, in order to manufacture a resin film for a high-frequency circuit board, a commercially available polyetheretherketone resin [manufactured by Victorec, product name: Victorex Granules 450G (hereinafter abbreviated as "450G")] is used as a polyetherketone resin. The mixture was prepared and dried in a dehumidifying hot air dryer heated to 160 ° C. for 12 hours or more.

After the polyetheretherketone resin was dried, this polyetheretherketone resin was provided near the screw root of a co-rotating twin-screw extruder [φ42 mm, L / D = 38, product name: K660 manufactured by Belstruf]. It was put into the hopper, which is the first supply port. In addition, the non-swelling synthetic mica was forcibly press-fitted from the second supply port of the side feeder immediately next to the vent port opened to the atmospheric pressure of the co-rotating twin-screw extruder. As this synthetic mica, a commercially available potassium tetrasilicon mica [manufactured by Katakura Corp. Agri, product name: Micromica MK-100, average particle size: 4.9 μm] was used.

After the polyetheretherketone resin was charged and the non-swellable synthetic mica was press-fitted in this way, the temperature of the barrel of the twin-screw extruder rotating in the same direction: 350 ° C to 370 ° C, the rotation speed of the screw: 150 rpm, per hour. Discharge rate: Melt-kneaded under the condition of 20 kg / hr and extruded into strands.

The molten state of the polyetheretherketone resin was visually observed from the vent port of the co-rotating twin-screw extruder. The polyetheretherketone resin and synthetic mica were added so as to be 25 parts by mass of synthetic mica with respect to 100 parts by mass of the polyetheretherketone resin. A strand-shaped extruded product was extruded from a co-rotating twin-screw extruder, and the extruded product was air-cooled and solidified, and then cut into pellets to prepare a molding material.

Next, the obtained molding material was put into a single-screw extruder with a T-die having a width of 900 mm and melt-kneaded, and the melt-kneaded molding material was continuously extruded from the T-die to obtain a resin film for a high-frequency circuit board. It was extruded into a strip shape. The single-screw extruder was of the type with L / D = 32, compression ratio: 2.5, and screw: full flight screw. The temperature of the single-screw extruder was adjusted to 380 to 400 ° C., the temperature of the T-die was adjusted to 400 ° C., and the temperature of the connecting pipe connecting the single-screw extruder and the T-die and the gear pump was adjusted to 400 ° C. When the molding material was charged into this single-screw extrusion molding machine, nitrogen gas 18 L / min was supplied through a non-volatile gas supply pipe.

After molding the resin film for the high frequency circuit board in this way, the resin film is formed into a pair of pressure-bonding rolls made of silicone rubber as shown in FIG. 2, and a plurality of metal rolls which are cooling rolls at 200 ° C., 230 ° C., and 250 ° C. The 6-inch take-up pipe of the take-up machine located downstream of these is sequentially wound, sandwiched between the crimping roll and the metal roll, and both sides of the continuous resin film are cut with a slit blade and taken up. A resin film having a length of 100 m and a width of 650 mm was produced by sequentially winding it around a tube. A slit blade that cuts both sides of the resin film is arranged so as to be able to move up and down between the crimping roll and the take-up pipe, and a tension roll that applies tension to the resin film is placed between the take-up pipe and the slit blade. Was rotatably supported.

After manufacturing the resin film, the thickness, mechanical properties, heating dimension stability, dielectric properties, and heat resistance of the resin film were evaluated and summarized in Table 1. The mechanical properties were evaluated by the tensile elastic modulus, the thermal dimensional stability was evaluated by the linear expansion coefficient, the dielectric properties were evaluated by the relative permittivity and the dielectric loss tangent, and the heat resistance was evaluated by the solder heat resistance.

-Film thickness of resin film for high-frequency circuit board The film thickness of the resin film for high-frequency circuit board was measured using a micrometer [Product name manufactured by Mitutoyo Co., Ltd .: Coolant Proof Micrometer Code MDC-25PJ]. At the time of measurement, arbitrary 10 points in the width direction (direction perpendicular to the extrusion direction) of the polyarylene ether ketone resin film were measured, and the average value thereof was taken as the film thickness.

-Relative crystallinity of the resin film for high-frequency circuit boards Regarding the relative crystallinity of the resin film for high-frequency circuit boards, weigh about 8 mg of the measurement sample from the resin film and measure it with a differential scanning calorimeter [manufactured by SII Nano Technologies]. Product name: EXSTAR7000 series X-DSC7000] was used to measure the temperature rise rate at 10 ° C./min and the measurement temperature range from 20 ° C. to 380 ° C. It was calculated from the calorific value of the crystal melting peak (J / g) and the calorific value of the recrystallization peak (J / g) obtained at this time using the following formula.

Relative crystallinity (%) = {1- (ΔHc / ΔHm)} × 100
Here, ΔHc represents the calorific value (J / g) of the recrystallization peak of the resin film under the heating condition of 10 ° C./min, and ΔHm is the crystal of the resin film under the heating condition of 10 ° C./min. It represents the calorific value (J / g) of the melting peak.

-Mechanical properties of the resin film for high-frequency circuit boards The mechanical properties of the resin film for high-frequency circuit boards were evaluated by the tensile elastic modulus at 23 ° C. The mechanical properties were measured in the extrusion direction and the width direction (direction perpendicular to the extrusion direction). The measurement was carried out in accordance with JIS K 7127 under the conditions of a tensile speed of 50 mm / min, a temperature of 23 ° C. ± 2 ° C., and a relative humidity of 50 RH ± 5% RH. The tensile elastic modulus was measured 5 times and the average value was taken as the tensile elastic modulus.

Dielectric characteristics of resin film for high-frequency circuit boards [Frequency: 1 GHz, 10 GHz]
The dielectric characteristics of the resin film for a high-frequency circuit board at a frequency of 1 GHz and 10 GHz were measured by a cavity resonator perturbation method using a network analyzer [PNA-L network analyzer N5230A manufactured by Agilent Technologies]. For the measurement of the dielectric property at 1 GHz, ASTMD2520 except that the cavity resonator was changed to the cavity resonator 1 GHz [Kanto Electronics Application Development Co., Ltd. model; CP431] and the cavity resonator 10 GHz [Kanto Electronics Application Development Co., Ltd. model; CP531]. It was carried out in accordance with. The measurement of the dielectric property was carried out in an environment of temperature: 23 ° C. ± 1 ° C. and humidity of 50% RH ± 5% RH.

Dielectric characteristics of resin film for high-frequency circuit boards [Frequency: around 28 GHz, around 76.5 GHz]
The frequency of the resin film for a high-frequency circuit board: around 28 GHz and around 76.5 GHz was measured by the Fabry-Perot method, which is a kind of open resonator method, using a vector network analyzer. The resonator is an open type resonator [manufactured by Keycom: Fabry-Perot resonator Model No. DPS03] was used.

At the time of measurement, a resin film for a high-frequency circuit board was placed on the sample table of the open resonator jig, and the measurement was performed by the Fabry-Perot method, which is a kind of open resonator method, using a vector network analyzer. Specifically, the relative permittivity and the dielectric loss tangent were measured by a resonance method utilizing the difference in resonance frequency between the state where the resin film was not placed on the sample table and the state where the resin film was placed. The specific frequencies used for measuring the dielectric properties are as shown in Table 4.

Measurement of the dielectric property, specifically, the dielectric property near 28 GHz and 76.5 GHz was measured by a predetermined measuring device under an environment of temperature: 24 ° C. and humidity of 40%. As a predetermined measuring device, a vector network analyzer E8631A [manufactured by Agilent Technologies: product name] was used near 28 GHz. At around 76.5 GHz, a vector network analyzer N5227A [manufactured by Agilent Technologies: product name] was used.

-Linear expansion coefficient of resin film for high-frequency circuit board The linear expansion coefficient of the resin film for high-frequency circuit board was measured in the extrusion direction and width direction (direction perpendicular to the extrusion direction) of the resin film. Specifically, when measuring the linear expansion coefficient in the extrusion direction of the resin film, the extrusion direction is 20 mm × 4 mm in the width direction, and when measuring the linear expansion coefficient in the width direction, the extrusion direction is 4 mm × 20 mm in the width direction. It was cut out to a size and measured. When measuring the coefficient of linear expansion, a load: 50 mN and a heating rate: 5 ° C./min were used in a tension mode using a thermomechanical analyzer [Product name: SII // SS7100 manufactured by Hitachi High-Tech Science Co., Ltd.]. From 25 ° C to 250 ° C at the rate of temperature rise: 5 ° C / min. The temperature was raised at the rate of 1 and the temperature change of the dimensions was measured, and the coefficient of linear expansion was determined by the inclination in the range of 25 ° C. to 125 ° C.

-Solder heat resistance of resin film for high-frequency circuit boards The solder heat resistance of resin films for high-frequency circuit boards conforms to the JIS C 5016 test method, and the resin film is floated in a solder bath at 288 ° C for 10 seconds and cooled to room temperature. After that, the presence or absence of deformation and wrinkles of the resin film was visually observed.
◯: When the resin film is not deformed or wrinkled ×: When the resin film is not deformed or wrinkled

[Example 2]
First, in order to manufacture a resin film for a high-frequency circuit board, a commercially available polyetheretherketone resin [manufactured by Solvay Specialty Polymers, product name: Ketaspire PEEK KT-851NL SP (hereinafter, "KT") is used as a polyetherketone resin. -851NL SP ")] was prepared, and this polyetheretherketone resin was dried for 12 hours or more in a dehumidifying hot air dryer heated to 160 ° C. For non-swelling synthetic mica, commercially available potassium tetrasilicon mica [Product name: Micromica MK-100DS, average particle size: 3.3 μm] manufactured by Katakura Corp. Agri Co., Ltd. was used.

Next, the polyetheretherketone resin and synthetic mica were prepared as a molding material for a resin film for a high-frequency circuit substrate by the same method as in Example 1. The polyetheretherketone resin and synthetic mica were mixed so as to be 35 parts by mass of synthetic mica with respect to 100 parts by mass of the polyetheretherketone resin.

After preparing the molding material, the resin film for the high frequency circuit board was extruded using this molding material by the same method as in Example 1. After the resin film was extruded, the thickness, mechanical properties, heating dimension stability, dielectric properties, and heat resistance of the resin film were evaluated by the same methods as in Example 1 and summarized in Table 1.

[Example 3]
First, in order to manufacture a resin film for a high-frequency circuit board, the polyetheretherketone resin used in Example 2 as the polyetherketone resin [manufactured by Solvay Specialty Polymers, product name: Ketaspire PEEK KT-851NL SP ( Hereinafter, it is abbreviated as “KT-851NL SP”)], and this polyetheretherketone resin and non-swellable synthetic mica are used as a molding material for a resin film for a high-frequency circuit substrate by the same method as in Example 1. Manufactured. As for the polyetheretherketone resin and synthetic mica, synthetic mica was added so as to be 45 parts by mass of synthetic mica with respect to 100 parts by mass of the polyetheretherketone resin. The synthetic mica was the potassium tetrasilicon mica of Example 1.

After preparing the molding material, the resin film for the high frequency circuit board was extruded using this molding material by the same method as in Example 1. After the resin film was extruded, the thickness, mechanical properties, heating dimension stability, dielectric properties, and heat resistance of the resin film were evaluated by the same methods as in Example 1 and summarized in Table 1.

[Example 4]
In order to manufacture a resin film for a high-frequency circuit board, a commercially available polyetheretherketone resin [manufactured by Victorec, product name: Victorex Granules 381G (hereinafter abbreviated as "381G")] is prepared as a polyetherketone resin. , This polyetheretherketone resin was dried for 12 hours or more in a dehumidifying hot air dryer heated to 160 ° C. As the synthetic mica, the potassium tetrasilicon mica of Example 1 was used.

Next, non-swelling synthetic mica was added to the polyetheretherketone resin so that the amount of synthetic mica was 45 parts by mass with respect to 100 parts by mass of the polyetheretherketone resin, and the polyetheretherketone resin and synthetic mica were carried out. It was produced as a molding material for a resin film for a high-frequency circuit substrate by the same method as in Example 1.

After preparing the molding material, the resin film for the high frequency circuit board was extruded using this molding material by the same method as in Example 1. After the resin film was extruded, the thickness, mechanical properties, heating dimension stability, dielectric properties, and heat resistance of the resin film were evaluated by the same methods as in Example 1 and shown in Table 2.

[Example 5]
Polyetheretherketone resin used in Example 4 as a polyarylene ether ketone resin for producing a resin film for a high-frequency circuit board [manufactured by Victorec, product name: Victorex Granules 381G (hereinafter abbreviated as "381G"). ] Was prepared, and this polyetheretherketone resin was dried for 12 hours or more in a dehumidifying hot air dryer heated to 160 ° C.

Next, a polyetheretherketone resin and a non-swellable synthetic mica were produced as a molding material for a resin film for a high-frequency circuit board by the same method as in Example 1. As the non-swelling synthetic mica, a commercially available potassium tetrasilicon mica [manufactured by Katakura Corp. Agri, product name: Micromica MK-300, average particle size: 11.9 μm] was used. Further, the polyetheretherketone resin and synthetic mica were added so as to be 65 parts by mass of synthetic mica with respect to 100 parts by mass of the polyetheretherketone resin.

After preparing the molding material, the resin film for the high frequency circuit board was extruded by the same method as in Example 1 using this molding material. After the resin film was extruded, the thickness, mechanical properties, heating dimension stability, dielectric properties, and heat resistance of the resin film were evaluated by the same methods as in Example 1 and shown in Table 2.

[Comparative Example 1]
The polyetheretherketone resin used in Example 1 was prepared, and the polyetheretherketone resin was dried in a dehumidifying dryer heated to 160 ° C. for 12 hours or more. After the polyetheretherketone resin is dried, the polyetheretherketone resin is set in a φ40 mm extrusion molding machine equipped with a 900 mm wide T-die and melt-kneaded, and the melt-kneaded polyetheretherketone resin is uniaxially extruded. A resin film for a high-frequency circuit substrate was extruded by continuously extruding from the T-die of the molding machine and then cooling with a metal roll heated to 200 ° C., 230 ° C., and 250 ° C. from the single-screw extruder side. The temperature of the φ40 mm single-screw extruder was 380 ° C to 400 ° C (confirmed), and the temperature of the T die was 400 ° C.

After the resin film for the high-frequency circuit board is extruded in this way, the resin film is subjected to a pair of crimping rolls made of silicone rubber as shown in FIG. 2, and metal rolls at 200 ° C., 230 ° C. , And the 6-inch take-up pipe of the take-up machine located downstream of these, and sandwiched between the crimping roll and the metal roll, and both sides of the continuous resin film are cut with a slit blade and wound. A resin film having a length of 100 m and a width of 650 mm was produced by sequentially winding it around a pipe. Once the resin film was obtained, the thickness, mechanical properties, heating dimensional stability, dielectric properties, and heat resistance of the resin film were evaluated by the same methods as in Example 1 and summarized in Table 3.

[Comparative Example 2]
The polyetheretherketone resin used in Example 2 was prepared, and the polyetheretherketone resin was dried in a dehumidifying dryer heated to 160 ° C. for 12 hours or more. After drying the polyetheretherketone resin for 12 hours or more in this way, this polyetheretherketone resin and calcium carbonate [manufactured by Toyo Fine Chemicals, product name: Whiten P-10, average particle size: 2.5 μm] are used as examples. It was prepared as a molding material for a resin film for a high-frequency circuit substrate by the same method as in 1. The polyetheretherketone resin and calcium carbonate were mixed so as to be 43 parts by mass of calcium carbonate with respect to 100 parts by mass of the polyetheretherketone resin.

Next, the resin film for the high frequency circuit board was extruded by the same method as in Example 1 using the molding material. After the resin film was extruded, the thickness, mechanical properties, heating dimension stability, dielectric properties, and heat resistance of the resin film were evaluated by the same methods as in Example 1 and summarized in Table 3.

[Comparative Example 3]
The polyetheretherketone resin used in Example 4 was prepared, and the polyetheretherketone resin was dried in a dehumidifying dryer heated to 160 ° C. for 12 hours or more. After the polyetheretherketone resin has been dried for 12 hours or more, the polyetheretherketone resin and amorphous silica [manufactured by Admatex, product name: SC5500-SQ, average particle size: 1.4 μm] are added to the polyether. Amorphous silica was mixed so as to be 37 parts by mass with respect to 100 parts by mass of the ether ketone resin.

Next, after preparing the molding material, a resin film for a high-frequency circuit board was extruded using this molding material by the same method as in Example 1. Once the resin film was obtained, the thickness, mechanical properties, heating dimension stability, dielectric properties, and heat resistance of the resin film were evaluated by the same methods as in Examples, and are shown in Table 3.

[Result]
The resin film for the high-frequency circuit board of each embodiment had a relative permittivity of 3.5 or less and a dielectric loss tangent of 0.005 or less. Further, as for the mechanical properties, since the tensile elastic modulus is 3500 N / mm ² or more and has high rigidity, the handleability at the time of assembling the high frequency circuit board is excellent. Regarding the thermal dimensional stability, the coefficient of linear expansion was 50 ppm / ° C or less, and better results than before were obtained. Further, regarding heat resistance, no deformation or wrinkles were observed even when the product was floated in a solder bath at 288 ° C. for 10 seconds, and it had heat resistance that could be used as a high-frequency circuit board.

On the other hand, the resin film for the high-frequency circuit board of the comparative example did not contain the non-swellable synthetic mica, so the coefficient of linear expansion was 55 ppm / ° C or higher, which was an insufficient result. From these measurement results, it was found that the resin film of each example has excellent dielectric properties and is most suitable for a high frequency circuit board used in a high frequency band from the MHz band to the GHz band.

The resin film, high frequency circuit board and its manufacturing method according to the present invention are used in the fields of information communication, automobile equipment and the like.

1 Resin film 2 Metal foil (metal layer)
3 Conductive layer 4 Molding material 10 Melt extrusion molding machine (extrusion molding machine)
11 Raw material input port 13 T die (dice)
16 Cooling roll 17 Crimping roll 18 Winding machine 19 Winding pipe 20 Slit blade

Claims (7)

1. A resin film characterized by containing 100 parts by mass of a polyarylene ether ketone resin and 10 parts by mass or more and 80 parts by mass or less of non-swelling synthetic mica.
2. The resin film according to claim 1, wherein the relative crystallinity is 80% or more.
3. The resin film according to claim 1 or 2, wherein the coefficient of linear expansion is 1 ppm / ° C. or higher and 50 ppm / ° C. or lower.
4. The resin film according to claim 1, 2 or 3, wherein the non-swellable synthetic mica is at least one of phlogopite fluorine, tetrasilicon mica potassium, and potassium teniolite.
5. A high-frequency circuit board having the resin film according to any one of claims 1 to 4.
6. The high-frequency circuit board according to claim 5, which includes a metal layer that is heat-sealed and laminated on a resin film.
7. The molding material according to claim 5 or 6, wherein the molding material contains at least 100 parts by mass of a polyarylene ether ketone resin and 10 parts by mass or more and 80 parts by mass or less of a non-swellable synthetic mica. By melt-kneading, the molding material is extruded into a resin film by a die of an extrusion molding machine, and the resin film is brought into contact with a cooling roll to be cooled, the relative crystallinity of the resin film is increased to 80% or more. , A method for manufacturing a high-frequency circuit board, characterized in that the linear expansion coefficient of this resin film is 1 ppm / ° C. or higher and 50 ppm / ° C. or lower.
   

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