Flat wire and manufacturing method thereof

Abstract

The present invention pertains to a flat wire provided with a flat conductor and a coating film of an insulating coating material that directly covers the entire circumferential direction of the flat conductor, the insulating coating material having a melt flow rate of 20.0-300.0 g / 10 minutes at a temperature of 372 DEG C and a load of 49 N, the insulating coating material contains a polyaryletherketone (A) and a fluorine-containing copolymer (B) having a tetrafluoroethylene-based unit, the content of the fluorine-containing copolymer (B) is 5 mass% or more with respect to the total mass of the polyaryletherketone (A) and the fluorine-containing copolymer (B) in the insulating coating material, and the flat wire has a tensile strength of 5.1. 2 flat wire in accordance with "JIS3216-3: 2011" in a winding test. The film of the insulating coating material does not peel off from the flat conductor.

Description

TECHNICAL FIELD

[0001] The present application relates to a flat wire and a manufacturing method thereof. This application claims priority based on Japanese Patent Application No. 2023-064886 filed on April 12, 2023, the contents of which are incorporated into this application. BACKGROUND

[0002] Vehicular equipment and the like used in automobiles, railways, aircraft, and the like are desired to be downsized and lightened. For this reason, a film of an insulating coating material of an insulating wire used in the vehicular equipment is required to be thinned. With high output power and high voltage of electrical equipment, the insulating coating material is also required to have excellent insulating properties and firm adhesion to a conductor.

[0003] By making a conductor of an electric wire into a flat conductor, a space factor when making a coil is higher compared to a round wire. As a result, it is possible to save a space of the entire coil, which contributes to downsizing of electrical equipment. However, in the case of a flat conductor, there is a problem that it is difficult to form a uniform film of an insulating coating material, and it is not possible to sufficiently maintain insulating properties compared to a round wire.

[0004] A manufacturing method of a flat wire is disclosed in Patent Literature 1, in which a film of an insulating coating layer having a thickness of 10 to 150 μm is formed on an outer periphery of a flat conductor by applying a powder having an average particle diameter of 0.02 μm or more and 150 μm or less on the flat conductor, the powder containing a melt-processable fluororesin having a melting point of 100°C or more and 325°C or less and having at least one functional group selected from a carbonyl group, a hydroxyl group, an epoxy group, and an isocyanate group. PRIOR ART DOCUMENTS PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Laid-Open No. 2017-204410 SUMMARY PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] However, in the manufacturing method described in Patent Literature 1, a preparation process of the powder and a firing process after the powder application are required, and there is a problem of low productivity. In addition, because the powder is to be applied, there is also a problem of low surface smoothness of the film of the insulating coating material. There are also problems of low conformability of the film of the insulating coating material to the flat conductor, easy generation of wrinkles in the film of the insulating coating material when the flat conductor is bent and deformed, and peeling of the film of the insulating coating material from the flat conductor.

[0007] The technical problem to be solved by the present invention is to provide a flat wire with high productivity, excellent surface smoothness of the insulating coating film and excellent conformability of the insulating coating film to the flat conductor when bent and deformed, and a method thereof for manufacturing the same. Technical solutions adopted to solve technical problems

[0008] The present invention has the following technical content. [1] A flat wire comprising a flat conductor having a rectangular cross-section in a direction perpendicular to the axial direction, and a film of an insulating coating material formed by extrusion directly covering the entire circumference of the flat conductor, wherein the melt flow rate of the insulating coating material at a temperature of 372°C and a load of 49N is 20.0–300.0 g / 10 min, the average thickness of the film of the insulating coating material is 10–1000 μm, and the unbiased standard deviation of the thickness of the film of the insulating coating material in the axial direction of the flat wire is less than 0.06 mm. The material comprises polyaryletherketone (A) and a fluorinated copolymer (B) having tetrafluoroethylene-based units, wherein the fluorinated copolymer (B) comprises one or more selected from fluorinated resins (B1) and fluorinated elastomers (B2) with melting points above 260°C, and the content of the fluorinated copolymer (B) is 5% by mass or more relative to the total mass of the polyaryletherketone (A) and the fluorinated copolymer (B) in the insulating coating material, and the film of the insulating coating material does not peel off from the flat conductor in a winding test according to "JIS 3216-3:2011 5.1.2 Flat Wire". [2] As described in [1], the flat wire has a cross-sectional area of ​​2.6 mm². 2 above. [3] A flat line as described in [1] or [2], wherein the fluorinated resin (B1) has a -CH2OH group, the content of which is 1 × 10⁻⁶ relative to the number of carbon atoms in the main chain of the fluorinated resin (B1). 6 More than 30. [4] The flat line as described in any one of [1] to [3], wherein the fluorinated elastomer (B2) has iodine atoms, and the content of the iodine atoms is more than 0.05% by mass relative to the total mass of the fluorinated elastomer (B2). [5] The flat wire as described in any one of [1] to [4], wherein the partial discharge initiation voltage of the insulating coating material is above 600 Vrms. [6] A flat wire manufacturing method of flat wire provided with a flat conductor having a rectangular cross section in a direction perpendicular to an axial direction, and a film of an insulating coating material formed by extrusion molding that directly covers the entire circumference of the flat conductor, the flat wire manufacturing method comprising the step of: using an extruder provided with a die, melting a composition containing a polyarylene ether ketone (A) and a fluorine-containing copolymer (B) having a unit based on tetrafluoroethylene (B), and extruding the melted composition from the die to the circumference of the flat conductor, thereby coating the flat conductor with the melted composition to form the insulating coating material, the insulating coating material having a melt flow rate of 20.0 to 300.0 g / 10 minutes at a temperature of 372°C and a load of 49 N, the film of the insulating coating material having an average thickness of 10 to 1000 μm, the flat wire having an unbiased standard deviation of the thickness of the film of the insulating coating material in the axial direction of less than 0.06 mm, the fluorine-containing copolymer (B) containing one or more selected from a fluorine-containing resin (B1) having a melting point of 260°C or higher and a fluorine-containing elastomer (B2), the content of the fluorine-containing copolymer (B) being 5% by mass or more with respect to the total mass of the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) in the composition, and the film of the insulating coating material not being peeled from the flat conductor in a winding test according to "JIS 3216-3:2011 5.1.2 Flat Wire". [7] The flat wire manufacturing method according to [6], wherein a draw ratio DDR calculated by the following formula 1 is 0.5 or more and less than 10.0, DDR = (D A -C 2 ) / (F A -C 2 ) Formula 1 In the formula 1, D A is an opening area (mm 2 ) of the die, C 2 is an area (mm 6 ) of a cross section in a direction perpendicular to the axial direction of the flat conductor, and F 2 is an area (mm 2 ) of a cross section in a direction perpendicular to the axial direction of the flat wire. [8] The flat wire manufacturing method according to [6] or [7], wherein the cross-sectional area of the flat conductor is 2.6 mm 2 or more. [9] The flat wire manufacturing method according to any one of [6] to [8], wherein the fluorine-containing resin (B1) has a -CH2OH group, and the content of the -CH2OH group is more than 30 per 1 x 10 2 carbon atoms of the main chain of the fluorine-containing resin (B1).

[10] The flat wire production method according to any one of [6] to [9], wherein the fluoroelastomer (B2) has iodine atoms, and the content of the iodine atoms is 0.05% by mass or more with respect to the total mass of the fluoroelastomer (B2).

[11] The flat wire production method according to any one of [6] to

[10] , wherein the partial discharge inception voltage of the insulating coating material is 600 Vrms or more. [1A] A flat wire provided with a flat conductor having a rectangular cross section in a direction perpendicular to an axial direction, and a skin film of an insulating coating material formed by extrusion molding that directly covers the entire circumference of the flat conductor, wherein a melt flow rate of the insulating coating material at a temperature of 372°C under a load of 49 N is 20.0 to 300.0 g / 10 minutes, 30.0 to 250.0 g / 10 minutes, 40.0 to 200.0 g / 10 minutes, or 50.0 to 230.0 g / 10 minutes, an average thickness of the skin film of the insulating coating material is 10 to 1000 μm, 20 to 500 μm, or 50 to 200 μm, an unbiased standard deviation of the thickness of the skin film of the insulating coating material in the axial direction of the flat wire is less than 0.06 mm, 0.03 mm or less, 0.01 mm or less, 0.001 mm or more and less than 0.06 mm, 0.001 to 0.03 mm, or 0.001 to 0.01 mm, the insulating coating material contains a polyaryletherketone (A) and a fluorine-containing copolymer (B) having a unit based on tetrafluoroethylene, the fluorine-containing copolymer (B) contains one or more selected from a fluorine-containing resin (B1) having a melting point of 260°C or more, 280°C or more, 290°C or more, 260 to 350°C, 280 to 340°C, or 290 to 330°C, and a fluoroelastomer (B2), and the content of the fluorine-containing copolymer (B) is 5% by mass or more, 5 to 45% by mass, or 10 to 30% by mass with respect to the total mass of the polyaryletherketone (A) and the fluorine-containing copolymer (B) in the insulating coating material, and in a winding test according to "JIS3216-3:2011 5.1.2 Flat Wire", the skin film of the insulating coating material is not peeled from the flat conductor. [2A] The flat wire according to [1A], wherein the cross-sectional area of the flat conductor is 2.6 mm 2 or more, 3.0 to 15 mm 2 or more, 3.0 to 15 mm 2 or more, 3.0 to 15 mm 2 . [3A] The flat wire according to [1A] or [2A], wherein the fluorine-containing resin (B1) has -CH2OH groups, the content of the -CH2OH groups being 1 x 10 6 more than 30, 60 or more, 150 or more, more than 30 and 5000 or less, 60 to 3000, or 150 to 1000. [4A] The flat wire according to any one of [1A] to [3A], wherein the fluorine-containing elastomer (B2) has iodine atoms, the content of the iodine atoms being 0.05% by mass or more, 0.1 to 5% by mass, or 0.2 to 1% by mass, relative to the total mass of the fluorine-containing elastomer (B2). [5A] The flat wire according to any one of [1A] to [4A], wherein the partial discharge inception voltage of the insulating coating material is 600 Vrms or more, 700 Vrms or more, 800 Vrms or more, 900 Vrms or more, 600 to 5000 Vrms, 700 to 4000 Vrms, 800 to 3000 Vrms, or 900 to 3000 Vrms. [6A] A flat wire manufacturing method of flat wire provided with a flat conductor having a rectangular cross section in a direction perpendicular to an axial direction, and a skin of an insulating coating material formed by extrusion molding that directly covers the entire circumference of the flat conductor, comprising a step of: using an extruder provided with a die, melting a composition containing a polyarylene ether ketone (A) and a fluorine-containing copolymer (B) having a unit based on tetrafluoroethylene (B), and extruding the melted composition from the die to the circumference of the flat conductor, thereby coating the flat conductor with the melted composition to form the insulating coating material, the melt flow rate of the insulating coating material being 20.0 to 300.0 g / 10 minutes, 30.0 to 250.0 g / 10 minutes, 40.0 to 200.0 g / 10 minutes, or 50.0 to 230.0 g / 10 minutes at a temperature of 372°C and a load of 49 N, the average thickness of the skin of the insulating coating material being 10 to 1000 μm, 20 to 500 μm, or 50 to 200 μm, the unbiased standard deviation of the thickness of the skin of the insulating coating material in the axial direction of the flat wire being less than 0.06 mm, 0.03 mm or less, 0.01 mm or less, 0.001 mm or more and less than 0.06 mm, 0.001 to 0.03 mm, or 0.001 to 0.01 mm, the fluorine-containing copolymer (B) containing one or more selected from a fluorine-containing resin (B1) having a melting point of 260°C or higher, 280°C or higher, 290°C or higher, 260 to 350°C, 280 to 340°C, or 290 to 330°C, and a fluorine-containing elastomer (B2), the content of the fluorine-containing copolymer (B) being 5% by mass or more, 5 to 45% by mass, or 10 to 30% by mass, with respect to the total mass of the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) in the composition, the skin of the insulating coating material not peeling from the flat conductor in a winding test according to "JIS 3216-3:2011 5.1.2 Flat Wire". [7A] The flat wire manufacturing method according to [6A], wherein a draw ratio DDR calculated by the following formula 1 is 0.1 or more and less than 10.0, 0.5 or more and less than 10.0, 0.5 to 5, or 0.8 to 1.5, DDR = (D A -C A ) / (F A -C A ) Formula 1 In the formula 1, D A is the opening area of the die (mm 2 ), C A is the area of the cross section of the flat conductor in the direction perpendicular to the axial direction (mm 2 ), and F Aarea (mm2) of a cross section of the flat wire in a direction perpendicular to the axial direction 2 ). [8A] The method for producing a flat wire according to [6A] or [7A], wherein the cross-sectional area of the flat conductor is 2.6 mm2or more, 3.0 mm2or more, 2.6 to 15 mm2, 3.0 to 15 mm2, or 2.6 to 15 mm2. 8 . 2 . 2 . 2 . [9A] The method for producing a flat wire according to any one of [6A] to [8A], wherein the fluorine-containing resin (B1) has -CH2OH groups, and the content of the -CH2OH groups is 1 x 10-4or more, 30 or more, 60 or more, 150 or more, 30 or less, 5000 or less, 60 to 3000, or 150 to 1000, with respect to the number of main chain carbons of the fluorine-containing resin (B1). 6 . [10A] The method for producing a flat wire according to any one of [6A] to [9A], wherein the fluorine-containing elastomer (B2) has iodine atoms, and the content of the iodine atoms is 0.05% by mass or more, 0.1 to 5% by mass, or 0.2 to 1% by mass, with respect to the total mass of the fluorine-containing elastomer (B2). [11A] The method for producing a flat wire according to any one of [6A] to [10A], wherein the partial discharge inception voltage of the insulating coating material is 600 Vrmsor more, 700 Vrmsor more, 800 Vrmsor more, 900 Vrmsor more, 600 to 5000 Vrms, 700 to 4000 Vrms, 800 to 3000 Vrms, or 900 to 3000 Vrms. Effects of the Invention

[0009] According to the present application, a flat wire having high productivity, excellent surface smoothness of the film of the insulating coating material, and excellent compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation, and a method for producing the same can be provided. DETAILED DESCRIPTION

[0010] The melt flow rate is the melt flow rate (MFR) defined in JIS K 7210-1:2014 (corresponding to International Standard ISO 1133-1:2011). Hereinafter, the melt flow rate is also referred to as MFR. The melt viscosity can be obtained by the method described in the examples. The average thickness of the film of the insulating coating material is obtained by taking 5 m of the flat wire, measuring the thickness of the film of the insulating coating material on the long side in the rectangular cross section in the direction perpendicular to the axial direction at every 100 mm, and performing arithmetic averaging. The unbiased standard deviation of the thickness of the skin of the insulating coating material in the axial direction of the flat wire is obtained by taking 5 m of the flat wire, measuring the thickness of the skin of the insulating coating material in the long side of the rectangular cross section in the direction perpendicular to the axial direction every 100 mm, and calculating from the measured values. The content of the -CH2OH group in the fluorine-containing resin (B1) can be obtained by infrared spectroscopy. Specifically, it can be obtained by the method described in the examples. The content of the iodine atom in the fluorine-containing elastomer (B2) can be obtained by ion chromatography. The melting point can be obtained as the temperature corresponding to the maximum value of the melting peak measured by differential scanning calorimetry (DSC) method. The partial discharge inception voltage of the insulating coating material can be obtained by the method described in the examples. The volume of the polyaryletherketone (A) or the fluorine-containing copolymer (B) is a value obtained by dividing the mass (g) of the polyaryletherketone (A) or the fluorine-containing copolymer (B) by its specific gravity (g / cm 3 ). The specific gravity of the polyaryletherketone (A) or the fluorine-containing copolymer (B) is a value measured by the water displacement (suspension) method at 23°C. The "number average particle diameter" of the fluorine-containing copolymer (B) is the average value of the maximum diameters of 100 randomly selected particles under optical microscope observation. The storage modulus G' of the fluorine-containing elastomer (B2) is a value measured at 100°C at 50 cpm based on ASTM D6204. The Mooney viscosity (ML 1+10 , 121°C) of the fluorine-containing elastomer (B2) is a value measured at 121°C according to JIS K6300-1:2000 (corresponding to international standards ISO 289-1:2005, ISO 289-2:1994). The welding strength, the heat expansion rate, and the Izod impact strength of the composition containing the polyaryletherketone (A) and the fluorine-containing copolymer (B) can be obtained by the methods described in the examples.

[0011] The unit of the polymer refers to a portion (polymerized unit) from a monomer that is formed by polymerization of the monomer. The unit can be a unit directly formed by polymerization reaction, or a unit in which a portion of the above unit is converted into another structure by treatment of the polymer. In this specification, the unit based on the monomer is also referred to as monomer unit.

[0012] Flat wire It has a flat conductor whose cross section in a direction perpendicular to the axial direction is rectangular, and a film of an insulating coating material formed by extrusion molding that directly covers the entire circumference of the flat conductor. The flat wire of the present embodiment is such that, in a winding test according to "JIS 3216-3:2011 5.1.2 Flat Wire", the film of the insulating coating material does not peel off from the flat conductor. In the case where the film of the insulating coating material does not peel off from the flat conductor in the winding test, the surface smoothness of the film of the insulating coating material and the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation are improved.

[0013] <Flat conductor> The flat conductor is a core wire of a flat wire, and is a conductor whose cross section in a direction perpendicular to the axial direction is rectangular. As the material of the flat conductor, a material known as the material of a core wire of an electric wire can be used, and examples thereof include copper, tin, silver, gold, aluminum, and alloys thereof. Among them, copper is preferable from the viewpoint of easy formation of the flat conductor. The thickness of the flat conductor is, for example, 0.5 mm to 3.0 mm. The width of the flat conductor is, for example, 1.0 mm to 5.0 mm. The thickness of the flat conductor is the short side of the rectangular cross section in the direction perpendicular to the axial direction. The width of the flat conductor is the long side of the rectangular cross section in the direction perpendicular to the axial direction.

[0014] The cross-sectional area of the flat conductor is preferably 2.6 mm 2 or more, and more preferably 3.0 mm 2 or more. The upper limit of the cross-sectional area of the flat conductor is not particularly limited, and is, for example, 15 mm 2 . The cross-sectional area of the flat conductor is preferably 2.6 to 15 mm 2 , and more preferably 3.0 to 15 mm 2 . The cross-sectional area of the flat conductor is the cross-sectional area in the direction perpendicular to the axial direction. In the case where the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation is low, the larger the cross-sectional area of the flat conductor, the more easily the film of the insulating coating material is likely to wrinkle at the time of bending deformation of the flat wire, and the more easily the film of the insulating coating material is likely to peel off from the flat conductor. The flat wire of the present embodiment is excellent in the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation, and thus the larger the cross-sectional area of the flat conductor, the more useful the flat wire is.

[0015] <Film of insulating coating material> The average thickness of the film of the insulating coating material is 10 to 1000 μm, preferably 20 to 500 μm, and more preferably 50 to 200 μm. If the average thickness of the film is equal to or greater than the lower limit value described above, the tracking resistance is excellent. If the average thickness of the film is equal to or less than the upper limit value described above, the overall thickness of the flat wire can be reduced, and when formed into a coil shape, the space of the entire coil can be saved, which contributes to the miniaturization of electrical equipment.

[0016] The thickness of the film of the insulating coating material in the axial direction of the flat wire has an unbiased standard deviation (hereinafter also referred to as "thickness variation") of less than 0.06 mm, preferably 0.03 mm or less, and more preferably 0.01 mm or less. If the thickness variation of the film is less than the upper limit value described above (or equal to or less than the upper limit value described above), the crack resistance during bending deformation and the tracking resistance are excellent. The thickness variation of the film is preferably 0.001 mm or more from the viewpoint of ease of manufacture and yield of the finished product. The thickness variation of the film is preferably 0.001 mm or more and less than 0.06 mm, 0.001 to 0.03 mm, or 0.001 to 0.01 mm. The lower limit value described above and the upper limit value described above can be appropriately combined. As examples of the combination, in the case where the thickness variation of the film is not 0, 0.001 mm or more and less than 0.06 mm, 0.001 to 0.03 mm, or 0.001 to 0.01 mm can be exemplified. In order to make the thickness variation less than 0.06 mm, it is preferable to form the film of the insulating coating material by extrusion molding in such a manner as to directly cover the entire circumference of the flat conductor. Other methods, such as forming the film of the insulating coating material by powder coating, are not preferable because the thickness variation tends to increase. In particular, compared with non-fluorine resins such as acrylic resins, epoxy resins, epoxy-acrylic resins, polyurethane resins, polyester resins, polyimide resins, polyamide-imide resins, and polyester-imide resins, in the case where the film of the insulating coating material is formed by powder coating, the fluorine-containing resin tends to have an increased variation because it is difficult to adjust the viscosity at the time of melting.

[0017] The MFR of the insulating coating material at a temperature of 372°C and a load of 49 N is 20.0 to 300.0 g / 10 minutes, preferably 30.0 to 250.0 g / 10 minutes, more preferably 40.0 to 200.0 g / 10 minutes, and further preferably 50.0 to 230.0 g / 10 minutes. The measurement of the MFR of the insulating coating material is preferably performed after 5 minutes of preheating at the measurement temperature (372°C). In addition, in the case where the MFR is 100.0 g / 10 minutes or more, the preheating time is preferably shortened. At this time, the preheating time is preferably 30 seconds to 180 seconds.

[0018] If the MFR of the insulating coating material at a temperature of 372°C under a load of 49 N is above the above lower limit value, the surface smoothness of the film of the insulating coating material and the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation are improved. If the MFR of the insulating coating material at a temperature of 372°C under a load of 49 N is below the above upper limit value, the strength of the film of the insulating coating material is improved.

[0019] The partial discharge inception voltage of the insulating coating material is preferably 600 Vrms or more, more preferably 700 Vrms or more, further preferably 800 Vrms or more, and particularly preferably 900 Vrms or more. The upper limit of the partial discharge inception voltage of the insulating coating material is not particularly limited, and for example, can be 5000 Vrms or less, can be 4000 Vrms or less, or can be 3000 Vrms or less. The partial discharge inception voltage of the insulating coating material is preferably 600 to 5000 Vrms, more preferably 700 to 4000 Vrms, further preferably 800 to 3000 Vrms, and particularly preferably 900 to 3000 Vrms.

[0020] If there is a minute gap-like defect or the like in the insulating coating material, an electric field is concentrated in that portion, and weak discharge occurs. This discharge is partial discharge. If the partial discharge inception voltage is above the above lower limit value, it means that the above defect is small. If the partial discharge inception voltage of the insulating coating material is above the above lower limit value, the adhesion of the insulating coating material to the flat conductor is improved. As a result, the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation is improved.

[0021] The insulating coating material contains a polyarylene ether ketone (A) and a fluorine-containing copolymer (B) having a unit based on tetrafluoroethylene. The insulating coating material can contain other components in addition to the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) as long as the characteristics thereof are not substantially impaired.

[0022] The total content of the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) is preferably 50% by mass or more, more preferably 70% by mass or more, and can be 100% by mass, with respect to the total mass of the insulating coating material.

[0023] The content of the fluorine-containing copolymer (B) is 5% by mass or more, preferably 5 to 45% by mass, and preferably 10 to 30% by mass, with respect to the total mass of the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) in the insulating coating material. That is, the content of the polyarylene ether ketone (A) is 95% by mass or less, preferably 55 to 95% by mass or more, and preferably 70 to 90% by mass, with respect to the total mass of the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) in the insulating coating material.

[0024] < Polyarylene Ether Ketone (A) > From the viewpoint of mechanical properties and heat resistance, polyether ketone (hereinafter also referred to as "PEK"), polyether ether ketone (hereinafter also referred to as "PEEK"), or polyether ketone ketone (hereinafter also referred to as "PEKK") are preferred as polyether ketone (A), with PEEK being particularly preferred. Polyaryletherketone (A) can be used in combination of two or more types, but it is preferred to use one type alone.

[0025] As a PEEK, a PEEK having repeating units represented by the following formula (I) is preferred.

[0026]

Chemistry 1

[0027] The melting point of polyaryletherketone (A) is preferably 200–430°C, more preferably 250–400°C, and even more preferably 280–380°C. If the melting point of polyaryletherketone is above the lower limit of the above range, the heat resistance of the insulating coating material is superior. If the melting point of polyaryletherketone is below the upper limit of the above range, the degradation of physical properties caused by the thermal decomposition of fluorinated copolymer (B) during the manufacture of flat wires can be suppressed, and the properties of fluorinated copolymer (B) (softness, impact resistance, chemical resistance, etc.) can be maintained.

[0028] The melt viscosity of polyaryletherketone (A) at a temperature of 390°C and a shear rate of 122 sec is... -1 Under the specified conditions, the preferred values ​​are 10–690 Pa·s, more preferably 50–500 Pa·s, and even more preferably 100–400 Pa·s. The MFR of polyaryletherketone (A) at a temperature of 372°C and a load of 49N is preferably 20.0 to 150.0 g / 10 min, more preferably 21.0 to 200.0 g / 10 min. If the melt viscosity and MFR of polyaryletherketone (A) are within the above range, it is easy to adjust the MFR of the insulating coating material to the above range.

[0029] Polyaryletherketone (A) can be a commercially available material or a material synthesized from various raw materials by various methods. Commercially available PEEK products include, for example, Victrex PEEK (manufactured by Victrex Corporation), VESTAKEEP series (manufactured by Dassault-Evonik Corporation), and Ketaspire (manufactured by Solvay Specailty Polymers). As a commercially available product of PEKK, for example, Kepstan (manufactured by Arkema) can be mentioned.

[0030] <Fluorine-containing copolymer (B)> The fluorine-containing copolymer (B) has a unit based on tetrafluoroethylene (hereinafter also referred to as "TFE"). The fluorine-containing copolymer (B) contains one or more selected from a fluorine-containing resin (B1) having a melting point of 260°C or higher and a fluorine-containing elastomer (B2).

[0031] (Fluorine-containing resin (B1)) The fluorine-containing resin (B1) has a melting point of 260°C or higher, preferably 280°C or higher, and further preferably 290°C or higher. If the melting point is higher than the lower limit value described above, the strength of the resulting insulation-coated material is excellent. The melting point of the fluorine-containing resin (B1) is preferably 350°C or lower, more preferably 340°C or lower, and further preferably 330°C or lower. If the melting point is lower than the upper limit value described above, the elongation of the resulting insulation-coated material is excellent. The lower limit value described above and the upper limit value described above can be appropriately combined. As examples of the combination, 260 to 350°C, 280 to 340°C, and 290 to 330°C can be mentioned.

[0032] The melt viscosity of the fluorine-containing resin (B1) is preferably 100 to 1400 Pa-s, more preferably 300 to 1300 Pa-s, and further preferably 500 to 1200 Pa-s, under the measurement conditions of a temperature of 390°C and a shear rate of 122 sec -1 The MFR of the fluorine-containing resin (B1) at a temperature of 372°C under a load of 49 N is preferably 10.0 to 300.0 g / 10 minutes, more preferably 12.0 to 200.0 g / 10 minutes, further preferably 15.0 to 150.0 g / 10 minutes, and particularly preferably 18 to 80 g / 10 minutes. If the melt viscosity and the MFR of the fluorine-containing resin (B1) are within the ranges described above, it is easy to adjust the MFR of the insulation-coated material to be within the range described above.

[0033] The fluorine-containing resin (B1) has a TFE unit and another unit other than the TFE unit.

[0034] As the other unit, a unit u1 based on a fluorine-containing monomer other than the TFE unit, a unit u2 based on a monomer having a functional group (but excluding the fluorine-containing monomer), and a unit u3 based on a non-fluorine-containing monomer (but excluding the monomer having a functional group) can be mentioned.

[0035] ​As the fluorine-containing monomer of the unit u1, a fluorine-containing compound having one polymerizable carbon-carbon double bond is preferred. For example, fluorinated olefins (for example, fluoroethylene, vinylidene fluoride, trifluoroethylene, hexafluoropropylene (hereinafter also referred to as "HFP"), chlorotrifluoroethylene, hexafluoroisobutene, etc.; except TFE), perfluoro(alkyl vinyl ether) (hereinafter also referred to as "PAVE"), CF2=CFOR f2 SO2X 1 (wherein, R f2 is a perfluoroalkylene group having 1 to 10 carbon atoms, which can have an oxygen atom between carbon atoms, and X 1 is a halogen atom or a hydroxyl group), CF2=CFOR f3 CO2X 2 (wherein, R f3 is a perfluoroalkylene group having 1 to 10 carbon atoms, which can have an oxygen atom between carbon atoms, and X 2 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), CF2=CF(CF2) p OCF=CF2(wherein, p is 1 or 2), fluoroalkyl ethylene (hereinafter also referred to as "FAE"), fluorine-containing monomers having a ring structure (for example, perfluoro(2,2-dimethyl-1,3-dioxolene), 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxolene, perfluoro(2-methylene-4-methyl-1,3-dioxolane), etc.), etc. The fluorine-containing monomer can be used alone as one kind, or two or more kinds in combination.

[0036] As the fluorine-containing monomer of the unit u1, from the viewpoint that the composition containing the fluorine-containing resin (B1) is excellent in moldability, at least one kind selected from the group consisting of HFP, PAVE and FAE is preferred, from the viewpoint that the electric properties (dielectric constant, dielectric loss tangent) and heat resistance are excellent, HFP, PAVE are more preferred, and PAVE is particularly preferred.

[0037] As the PAVE, for example, CF2=CFOR f2 (wherein, R f2 is a perfluoroalkyl group having 1 to 10 carbon atoms, which can have an oxygen atom between carbon atoms) can be exemplified. As a specific example of the PAVE, CF2=CFOCF2CF3, CF2=CFOCF2CF2CF3 (hereinafter also referred to as "PPVE"), CF2=CFOCF2CF2CF2CF3, CF2=CFO(CF2)6F can be exemplified. As the PAVE, PPVE is preferred.

[0038] As the FAE, for example, CH2=CX 3 (CF2) q X 4 (wherein, X 3is a hydrogen atom or a fluorine atom, q is an integer of 2 to 10, X 4 is a hydrogen atom or a fluorine atom. As the specific examples of the FAE, CH2=CF(CF2)2F, CH2=CF(CF2)3F, CH2=CF(CF2)4F, CH2=CF(CF2)5F, CH2=CF(CF2)6F, CH2=CF(CF2)2H, CH2=CF(CF2)3H, CH2=CF(CF2)4H, CH2=CF(CF2)5H, CH2=CF(CF2)6H, CH2=CH(CF2)2F, CH2=CH(CF2)3F, CH2=CH(CF2)4F, CH2=CH(CF2)5F, CH2=CH(CF2)6F, CH2=CH(CF2)2H, CH2=CH(CF2)3H, CH2=CH(CF2)4H, CH2=CH(CF2)5H, CH2=CH(CF2)6H can be exemplified. As the FAE, CH2=CH(CF2) q 1X 4 (wherein, q1 is 2 to 6, preferably 2 to 4), more preferably CH2=CH(CF2)2F, CH2=CH(CF2)3F, CH2=CH(CF2)4F, CH2=CF(CF2)3H, CH2=CF(CF2)4H, particularly preferably CH2=CH(CF2)4F, CH2=CH(CF2)2F.

[0039] As the monomer having a functional group of the unit u2, a monomer having a carboxyl group (for example, maleic acid, itaconic acid, citraconic acid, undecylenic acid, etc.), a monomer having an acid anhydride group (for example, itaconic anhydride (hereinafter also referred to as "IAH"), citraconic anhydride (hereinafter also referred to as "CAH"), 5-norbornene-2,3-dicarboxylic anhydride (hereinafter also referred to as "NAH"), maleic anhydride, etc.), a monomer having a hydroxyl group and an epoxy group (for example, hydroxybutyl vinyl ether, glycidyl vinyl ether, etc.), etc. can be exemplified. The monomer having a functional group can be used alone by one kind, or can be used in combination of two or more kinds. The acid anhydride group means a group represented by -C(=O)-O-C(=O)-.

[0040] As the monomer having a functional group of the unit u2, a monomer having an acid anhydride group is preferable, and it is preferably selected from one or more kinds of IAH, CAH and NAH, more preferably IAH or NAH, further preferably NAH. If one or more kinds selected from IAH, CAH and NAH are used, the fluorine-containing resin (Bl) having an acid anhydride group can be easily produced without using a special polymerization method necessary when maleic anhydride is used (refer to Japanese Patent Application Laid-Open No. 11-193312).

[0041] As the fluorine-free monomer of the unit u3, a fluorine-free compound having one polymerizable carbon-carbon double bond is preferred, and examples thereof include olefins (e.g., ethylene, propylene, 1-butene, etc.), vinyl esters (e.g., vinyl acetate, etc.). The fluorine-free monomer can be used alone or in combination of two or more.

[0042] As the fluorine-containing resin (B1), a fluorine-containing resin having a TFE unit and a PAVE unit (hereinafter also referred to as "PFA"), a fluorine-containing resin having a TFE unit and a HFP unit (hereinafter also referred to as "FEP"), a fluorine-containing resin having a TFE unit and an ethylene unit are preferred from the viewpoints of the point characteristics (dielectric constant, dielectric loss tangent) and heat resistance, and the PFA, the FEP, and particularly the PFA are preferred.

[0043] The fluorine-containing resin (B1) preferably has at least one functional group selected from a carbonyl group-containing group, a hydroxyl group, an epoxy group, and an isocyanate group. The fluorine-containing resin (B1) is easily dispersed in the polyaryletherketone (A) by having the functional group. In addition, the functional group bonds to the atoms of the surface of the flat conductor, and the adhesion of the insulating coating material to the flat conductor is improved. As a result, the conformability of the film of the insulating coating material to the flat conductor at the time of bending deformation is improved. The functional group is preferably present as either or both of a terminal group of the main chain and a side group of the main chain of the fluorine-containing resin (B1). The main chain refers to the main carbon chain of a chain compound, and is the main trunk portion having the largest number of carbons.

[0044] As the functional group, a carbonyl group-containing group is preferred from the viewpoint of dispersibility in the polyaryletherketone (A). The carbonyl group-containing group is a group having a carbonyl group -C(=O)- in the structure. As the carbonyl group-containing group, examples include a group having a carbonyl group between carbon atoms of a hydrocarbon group, a carbonate group, a carboxyl group, a halogenated formyl group, an alkoxy carbonyl group, an acid anhydride group. As the hydrocarbon group in the group having a carbonyl group between carbon atoms of a hydrocarbon group, examples include an alkylene group having 2 to 8 carbons. In addition, the number of carbons of the alkylene group is the number of carbons excluding the carbon constituting the carbonyl group. The alkylene group can be linear or branched. The halogenated formyl group is represented by -C(=O)-X (where X is a halogen atom). As the halogen atom in the halogenated formyl group, examples include a fluorine atom, a chlorine atom, etc., and a fluorine atom is preferred. That is, as the halogenated formyl group, a fluorinated formyl group (also referred to as a carbonyl fluoride group) is preferred. As the alkoxy group in the alkoxy carbonyl group, an alkoxy group having 1 to 8 carbons is preferred, and a methoxy group or an ethoxy group is particularly preferred. The alkoxy group can be linear or branched.

[0045] As the fluorine-containing resin (B1) having a functional group, depending on the manufacturing method, for example, the following fluorine-containing resins can be exemplified. Fluororesin (B1-1): a fluororesin having a functional group derived from at least one selected from the group consisting of a monomer, a chain transfer agent, and a polymerization initiator used at the time of production of the fluororesin. Fluororesin (B1-2): a fluororesin obtained by introducing a functional group into a fluororesin having no functional group by surface treatment such as corona discharge treatment, plasma treatment, or the like. Fluororesin (B1-3): a fluororesin obtained by graft-polymerizing a monomer having a functional group onto a fluororesin having no functional group. As the fluororesin having a functional group, the fluororesin (B1-1) is preferable.

[0046] In the case where the functional group in the fluororesin (B1-1) is derived from a monomer used at the time of production of the fluororesin (B1-1), as the monomer, only a monomer having a functional group of the unit u2 described above needs to be used.

[0047] In the case where the functional group in the fluororesin (B1-1) is derived from a chain transfer agent used at the time of production of the fluororesin (B1-1), as the chain transfer agent, only a chain transfer agent having a functional group such as acetic acid, acetic anhydride, methyl acetate, ethylene glycol, propylene glycol, or the like needs to be used. In this case, the functional group exists as a terminal group of the main chain of the fluororesin (B1-1).

[0048] In the case where the functional group in the fluororesin (B1-1) is derived from a polymerization initiator used at the time of production of the fluororesin (B1-1), as the polymerization initiator, only a polymerization initiator having a functional group such as di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, t-butyl isopropyl peroxydicarbonate, bis(4-t-butylcyclohexyl) peroxydicarbonate, di(2-ethylhexyl) peroxydicarbonate, or the like needs to be used. In this case, the functional group exists as a terminal group of the main chain of the fluororesin (B1-1).

[0049] The functional group in the fluororesin (B1-1) can be derived from two or more of the monomer, the chain transfer agent, and the polymerization initiator used at the time of production of the fluororesin (B1-1).

[0050] As the fluororesin (B1-1), from the viewpoint of being able to easily control the content of the functional group, a fluororesin having a functional group derived from a monomer used at the time of production of the fluororesin (B1-1) is preferable. As the fluororesin (B1-1) having a functional group derived from a monomer, from the viewpoint of thermal stability, a fluoropolymer having a unit u2 based on a cyclic hydrocarbon monomer having an acid anhydride group (hereinafter also referred to as "acid anhydride group-containing cyclic hydrocarbon monomer"), a TFE unit, and a unit u1 based on a fluorine-containing monomer other than the TFE unit is preferable. The acid anhydride group of the unit u2 corresponds to the functional group.

[0051] The content of the functional group in the fluororesin (B1) is preferably 1 x 10 6 Preferably, the content of the functional group is 10 to 60,000, more preferably 100 to 50,000, further preferably 100 to 10,000, particularly preferably 300 to 5,000. If the content of the functional group is above the lower limit value described above, dispersibility is excellent, and if it is below the upper limit value described above, heat stability is excellent. The content of the functional group can be determined by nuclear magnetic resonance (NMR) analysis, infrared absorption spectrum analysis, or the like. For example, using infrared absorption spectrum analysis or the like as described in Japanese Patent Application Publication No. 2007-314720, the content of the functional group can be calculated from the proportion (mole %) of the units having the functional group among all the units constituting the fluororesin (B1).

[0052] The fluororesin (B1) preferably has a -CH2OH group as the functional group. The content of the -CH2OH group is preferably greater than 30, more preferably 60 or greater, further preferably 150 or greater, with respect to 1 x 10 6 6 Preferably, the content of the -CH2OH group is 1 x 10 6 Preferably, the content of the -CH2OH group is 1 x 10

[0053] If the content of the -CH2OH group in the fluororesin (B1) is above the lower limit value described above, the -CH2OH group bonds with the atoms of the flat conductor surface, and the adhesion of the insulating coating material to the flat conductor is improved. As a result, the conformability of the insulating coating material film to the flat conductor is improved during bending deformation.

[0054] In addition, by performing fluorination treatment on the fluororesin (B1) having a -CH2OH group, the amount of the -CH2OH group can be reduced. Furthermore, by controlling the type and amount of the chain transfer agent, the polymerization initiator, the monomers, and the reaction conditions, the amount of the -CH2OH group can also be controlled.

[0055] The preferred content and ratio of each unit of the fluororesin (B1) are as described below. The content of the TFE unit is preferably 90.0 to 99.9 mole %, more preferably 95.0 to 99.5 mole %, further preferably 96.0 to 99.0 mole %, with respect to the total amount of the structural units of the fluororesin (B1).

[0056] In the case where the fluorine-containing resin (B1) contains the unit u1, the content of the unit u1 is preferably 0.1 to 10.0 mol%, more preferably 0.5 to 5.0 mol% relative to the total amount of the structural units of the fluorine-containing resin (B1). In the case where the fluorine-containing resin (B1) contains the unit u2, the content of the unit u2 is preferably 0.01 to 1.0 mol%, more preferably 0.05 to 0.5 mol% relative to the total amount of the structural units of the fluorine-containing resin (B1). In the case where the fluorine-containing resin (B1) contains the unit u3, the content of the unit u3 is preferably more than 0 mol% and 1.0 mol% or less relative to the total amount of the structural units of the fluorine-containing resin (B1). In one embodiment, the fluorine-containing resin (B1) preferably does not contain the unit u3. In the case where the fluorine-containing resin (B1) contains any one of the unit u1 to the unit u3, the total content of the unit u1 to the unit u3 is preferably 0.01 to 10.0 mol%, more preferably 0.05 to 5.0 mol% relative to the total amount of the structural units of the fluorine-containing resin (B1). In the case where the fluorine-containing resin (B1) contains any one of the unit u1 to the unit u3, the total content of the TFE unit and the unit u1 to the unit u3 is preferably 90 mol% or more, more preferably 95 mol% or more, and further preferably 100 mol% relative to the total amount of the structural units of the fluorine-containing resin (B1).

[0057] If the content of each unit is within the above range, the surface smoothness of the film of the insulating coating material and the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation are improved in the resulting flat wire.

[0058] The ratio of each unit can be calculated by melt NMR analysis, fluorine content analysis, infrared absorption spectrum analysis, or the like of the fluorine-containing resin (B1).

[0059] In the fluorine-containing resin (B1), a part of the anhydride group in the unit u2 is hydrolyzed, and as a result, a unit based on a dicarboxylic acid (itaconic acid, citraconic acid, 5-norbornene-2,3-dicarboxylic acid, maleic acid, or the like) corresponding to the cyclic hydrocarbon monomer having an anhydride group can sometimes be contained. In the case where the unit based on the dicarboxylic acid is contained, the unit is regarded as the unit u2.

[0060] As preferable specific examples of the fluorine-containing resin (B1), as a copolymer of TFE and PAVE, there can be mentioned a TFE / PPVE copolymer, a TFE / PAVE / NAH copolymer, and the like. As a copolymer of TFE and HFP, there can be mentioned a TFE / HFP copolymer, a TFE / HFP / PAVE copolymer, and the like. As a copolymer of TFE and E, there can be mentioned a TFE / E / HFP copolymer, a TFE / E / CH2=CH(CF2)2F copolymer, a TFE / E / CH2=CH(CF2)4F copolymer, a TFE / E / CH2=CH(CF2)2F / CH2=CH(CF2)4F copolymer, a TFE / E / HFP / IAH copolymer, a TFE / E / CH2=CH(CF2)2F / IAH copolymer, a TFE / E / CH2=CH(CF2)4F / IAH copolymer, a TFE / E / CH2=CH(CF2)2F / CH2=CH(CF2)4F / IAH copolymer, and the like.

[0061] The fluorine-containing resin (B1) can use a material manufactured by a publicly known manufacturing method, or a commercially available material. As the publicly known manufacturing method, for example, there can be mentioned the methods described in International Publication No. 2015 / 182702, International Publication No. 2016 / 006644, and International Publication No. 2016 / 017801.

[0062] (Fluorine-containing elastomer (B2)) The fluorine-containing elastomer (B2) is different from the fluorine-containing resin (B1), and is a fluorine-containing elastomeric copolymer which shows an energy storage modulus G' of 80 or more at 100°C and 50 cpm and does not have a melting point.

[0063] The melt viscosity of the fluorine-containing elastomer (B2) is preferably 10 to 2500 Pa-s, more preferably 100 to 2300 Pa-s, and further preferably 200 to 2000 Pa-s, under the measurement conditions of a temperature of 300°C and a shear rate of 122 sec -1 The MFR of the fluorine-containing elastomer (B2) at a temperature of 230°C and under a load of 21 N is preferably 0.1 to 300.0 g / 10 minutes, more preferably 1.0 to 200.0 g / 10 minutes, and further preferably 40.0 to 150.0 g / 10 minutes. If the melt viscosity and the MFR of the fluorine-containing elastomer (B2) are within the above ranges, it is easy to adjust the MFR of the insulating coating material to within the above ranges.

[0064] ​The storage modulus G' of the fluorine-containing elastomer (B2) is preferably 80 to 800 kPa, more preferably 100 to 800 kPa, and further preferably 120 to 600 kPa. The greater the storage modulus G' of the fluorine-containing elastomer (B2), the greater the molecular weight and the higher the entanglement density of the molecular chain. If the storage modulus G' of the fluorine-containing elastomer (B2) is within the above range, the mechanical properties such as the tensile strength of the insulation-coated material are more excellent.

[0065] The number average molecular weight of the fluorine-containing elastomer (B2) is preferably 10,000 to 1,500,000, more preferably 20,000 to 1,000,000, further preferably 20,000 to 800,000, and particularly preferably 50,000 to 600,000. If the number average molecular weight of the fluorine-containing elastomer (B2) is above the lower limit of the above range, the impact resistance and the mechanical properties of the insulation-coated material are excellent. If the number average molecular weight of the fluorine-containing elastomer (B2) is below the upper limit of the above range, the flowability and the dispersibility in the polyaryletherketone (A) are excellent. As a result, the flexibility is improved. The number average molecular weight refers to the polystyrene conversion molecular weight determined using GPC with tetrahydrofuran as the eluent, using a polystyrene polymer of known molecular weight to prepare a calibration curve.

[0066] The Mooney viscosity (ML 1+10 , 121°C) of the fluorine-containing elastomer (B2) is preferably 10 to 300, more preferably 20 to 280, and further preferably 30 to 250. The Mooney viscosity is an index of the molecular weight. The greater the value of the Mooney viscosity, the greater the molecular weight. The smaller the value of the Mooney viscosity, the smaller the molecular weight. If the Mooney viscosity (ML 1+10 , 121°C) of the fluorine-containing elastomer (B2) is above the lower limit of the above range, the impact resistance and the mechanical properties of the insulation-coated material are excellent. If the Mooney viscosity (ML 1+10 , 121°C) of the fluorine-containing elastomer (B2) is below the upper limit of the above range, the flowability and the dispersibility in the polyaryletherketone (A) are excellent. As a result, the moldability of the composition containing the fluorine-containing elastomer (B2) is excellent.

[0067] The fluorine-containing elastomer (B2) has TFE units and other units than TFE units.

[0068] As the other units, the following units based on monomer m1, units based on monomer m2, and units based on monomer m3 can be exemplified.

[0069] The monomer m1 is at least one monomer selected from the group consisting of HFP, vinylidene fluoride (hereinafter also referred to as "VdF"), and chlorotrifluoroethylene. The monomer m1 can be used alone or in combination of two or more kinds, and is preferably used alone. In addition, the monomer m1 can not be used.

[0070] The monomer m2 is at least one monomer selected from the group consisting of ethylene (hereinafter also referred to as "E"), propylene (hereinafter also referred to as "P"), PAVE, fluoroethylene (hereinafter also referred to as "VF"), 1,2-difluoroethylene (hereinafter also referred to as "DiFE"), 1,1,2-trifluoroethylene (hereinafter also referred to as "TrFE"), 3,3,3-trifluoro-1-propene (hereinafter also referred to as "TFP"), 1,3,3,3-tetrafluoropropene, and 2,3,3,3-tetrafluoropropene.

[0071] As the PAVE, in addition to the above-mentioned PPVE, CF2=CFOCF2CF2CF2CF3, and CF2=CFO(CF2)6F, CF2=CFOCF3 (hereinafter also referred to as "PMVE") can be exemplified. Among them, as the PAVE, PMVE and PPVE are preferred, and PMVE is more preferred. The PAVE can be used alone or in combination of two or more kinds.

[0072] The monomer m3 is a monomer capable of copolymerizing with TFE, having any one of iodine atom, epoxy group, and anhydride group at the molecular terminal. By using the monomer m3, any one of iodine atom, epoxy group, and anhydride group can be introduced into the fluorine-containing elastomer (B2). The proportion of the monomer m3 unit is preferably 20 mol% or less, more preferably 5 mol% or less, and particularly preferably 0 mol% with respect to the total units constituting the fluorine-containing elastomer (B2).

[0073] As the monomer m3 having iodine atom at the molecular terminal, for example, vinyl iodide, 4-iodo-3,3,4,4-tetrafluoro-1-butene, 2-iodo-1,1,2,2-tetrafluoro-1-vinyloxyethane, 2-iodoethyl vinyl ether, allyl iodide, 1,1,2,3,3,3-hexafluoro-2-iodo-1-(perfluoroethenyloxy)propane, 3,3,4,5,5,5-hexafluoro-4-iodopentene, iodotrifluoroethylene, and 2-iodoperfluoro(ethyl vinyl ether) can be exemplified. The monomer m3 having iodine atom at the molecular terminal can be used alone or in combination of two or more kinds.

[0074] As the monomer m3 having epoxy group at the molecular terminal, for example, glycidyl (meth)acrylate, β-methyl glycidyl (meth)acrylate, and the like (glycidyl esters of (meth)acrylic acid); allyl glycidyl ether, allyl methyl glycidyl ether, and the like (allyl glycidyl ethers); 3,4-epoxycyclohexyl acrylate, 3,4-epoxycyclohexyl methacrylate, and the like (vinyl monomers containing alicyclic epoxy group) can be exemplified. The monomer m3 having an epoxy group at the molecular terminal can be used alone or in combination of two or more kinds.

[0075] As the monomer m3 having an anhydride group at the molecular terminal, for example, itaconic anhydride, citraconic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, maleic anhydride can be exemplified. The monomer m3 having an anhydride group at the molecular terminal can be used alone or in combination of two or more kinds.

[0076] As examples of the fluorine-containing elastomer (B2), the following two kinds of fluorine-containing copolymers can be exemplified. • a copolymer having a TFE unit and a P unit. • a copolymer having a TFE unit and a PAVE unit (but a copolymer having a P unit or a VdF unit is excluded) The total proportion of each unit specifically shown in the two kinds of fluorine-containing elastomers is preferably 50 mol% or more with respect to the total units constituting the fluorine-containing elastomer.

[0077] As the copolymer having a TFE unit and a P unit, for example, the following copolymers can be exemplified. a copolymer composed of a TFE unit and a P unit, a copolymer composed of a TFE unit, a P unit and a VF unit, a copolymer composed of a TFE unit, a P unit and a VdF unit, a copolymer composed of a TFE unit, a P unit and an E unit, a copolymer composed of a TFE unit, a P unit and a TFP unit, a copolymer composed of a TFE unit, a P unit and a PAVE unit, a copolymer composed of a TFE unit, a P unit and a 1,3,3,3-tetrafluoropropene unit, a copolymer composed of a TFE unit, a P unit and a 2,3,3,3-tetrafluoropropene unit, a copolymer composed of a TFE unit, a P unit and a TrFE unit, a copolymer composed of a TFE unit, a P unit and a DiFE unit, a copolymer composed of a TFE unit, a P unit and a VdF unit and a TFP unit, a copolymer composed of a TFE unit, a P unit, a VdF unit and a PAVE unit. Among them, as the copolymer having a TFE unit and a P unit, a copolymer composed of a TFE unit and a P unit is preferred.

[0078] As the copolymer having a TFE unit and a PAVE unit, for example, a copolymer composed of a TFE unit and a PAVE unit can be exemplified. Among them, a copolymer composed of a TFE unit and a PMVE unit, a copolymer composed of a TFE unit, a PMVE unit and a PPVE unit, a copolymer composed of a TFE unit and a PMVE unit are preferable, and a copolymer composed of a TFE unit and a PMVE unit is more preferable.

[0079] As other examples of the fluorine-containing elastomer (B2), for example, a copolymer composed of a TFE unit, a VdF unit and a 2,3,3,3-tetrafluoropropene unit can be exemplified.

[0080] As the fluorine-containing elastomer (B2), a copolymer having a TFE unit and a P unit, a copolymer having a TFE unit and a PAVE unit are preferable, a copolymer having a TFE unit and a P unit is more preferable, and a copolymer composed of a TFE unit and a P unit is particularly preferable. The copolymer composed of a TFE unit and a P unit is excellent in heat stability at the time of manufacturing a flat wire, and thus stability of transportability at the time of manufacturing a flat wire is stable. Further, coloring and foaming of the insulating coating material are reduced.

[0081] From the viewpoint of easily contributing to the impact resistance of the insulating coating material, the proportion of each unit constituting the fluorine-containing elastomer (B2) is preferably in the following range. The molar ratio of each unit (hereinafter, referred to as "TFE : P", and the same applies to other molar ratios) in the copolymer composed of a TFE unit and a P unit is preferably 30 to 80 : 70 to 20, more preferably 40 to 70 : 60 to 30, and further preferably 50 to 60 : 50 to 40. The TFE : P : VF in the copolymer composed of a TFE unit, a P unit and a VF unit is preferably 30 to 60 : 60 to 20 : 0.05 to 40. The TFE : P : VdF in the copolymer composed of a TFE unit, a P unit and a VdF unit is preferably 30 to 60 : 60 to 20 : 0.05 to 40. The TFE : P : E in the copolymer composed of a TFE unit, a P unit and an E unit is preferably 20 to 60 : 70 to 30 : 0.05 to 40. The TFE : P : TFP in the copolymer composed of a TFE unit, a P unit and a TFP unit is preferably 30 to 60 : 60 to 30 : 0.05 to 20. The TFE : P : PAVE in the copolymer composed of a TFE unit, a P unit and a PAVE unit is preferably 40 to 70 : 60 to 29.95 : 0.05 to 20. The TFE:P:2,3,3,3-tetrafluoropropene in the copolymer composed of TFE units, P units and 2,3,3,3-tetrafluoropropene units is preferably 30-60:60-20:0.05-40. The TFE:P:2,3,3,3-tetrafluoropropene in the copolymer composed of TFE units, P units and 2,3,3,3-tetrafluoropropene units is preferably 30-60:60-20:0.05-40. The TFE:P:TrFE in the copolymer composed of TFE units, P units and TrFE units is preferably 30-60:60-20:0.05-40. The TFE:P:DiFE in the copolymer composed of TFE units, P units and DiFE units is preferably 30-60:60-20:0.05-40. The TFE:P:VdF:TFP in the copolymer composed of TFE units, P units, VdF units and TFP units is preferably 30-60:60-20:0.05-40:0.05-20. The TFE:P:VdF:PAVE in the copolymer composed of TFE units, P units, VdF units and PAVE units is preferably 30-70:60-20:0.05-40:0.05-20.

[0082] The TFE:VdF:HFP in the copolymer composed of TFE units, VdF units and HFP units is preferably 20-60:1-40:20-60. The TFE:VdF:HFP:TFP in the copolymer composed of TFE units, VdF units, HFP units and TFP units is preferably 30-60:0.05-40:60-20:0.05-20. The TFE:VdF:HFP:PAVE in the copolymer composed of TFE units, VdF units, HFP units and PAVE units is preferably 30-70:60-20:0.05-40:0.05-20.

[0083] The TFE:PAVE in the copolymer composed of TFE units and PAVE units is preferably 40-70:60-30. The TFE:PMVE in the copolymer composed of TFE units and PMVE units is preferably 40-70:60-30. The TFE:PMVE:PPVE in the copolymer composed of TFE units, PMVE units and PPVE units is preferably 40-70:3-57:3-57.

[0084] The TFE:VdF:2,3,3,3-tetrafluoropropene in the copolymer composed of TFE units, VdF units, and 2,3,3,3-tetrafluoropropene units is preferably 1 to 30:30 to 90:5 to 60.

[0085] The fluorine-containing elastomer (B2) can be used alone or in combination of two or more, but is preferably used alone. The fluorine-containing elastomer (B2) can be a commercially available material or a material synthesized from various raw materials by various methods. The fluorine-containing elastomer (B2) can be synthesized, for example, by polymerizing any one or more of TFE, monomer ml, monomer m2, and monomer m3.

[0086] A radical polymerization initiator is preferably used at the time of polymerization. As the radical polymerization initiator, a compound having a half-life of 10 hours at a temperature of 0 to 100°C is preferable, and a compound having a temperature of 20 to 90°C is particularly preferable. Examples include azo compounds (azobisisobutyronitrile, etc.), non-fluorine-based diacyl peroxides (diisobutyryl peroxide, dicaprylyl peroxide, benzoyl peroxide, lauryl peroxide, etc.), peroxydicarbonates (diisopropyl peroxydicarbonate, etc.), peroxy esters (tert-butyl peroxy pivalate, tert-butyl peroxy isobutyrate, tert-butyl peroxy acetate, etc.), fluorine-containing diacyl peroxides (Compound 1 represented by the following formula Fl), and inorganic peroxides (potassium persulfate, sodium persulfate, ammonium persulfate, etc.). (Z(CF2) r COO)2··· Formula F1 In the formula Fl, Z is a hydrogen atom, a fluorine atom, or a chlorine atom, and r is an integer of 1 to 10.

[0087] A chain transfer agent can be used at the time of polymerization. Examples of the chain transfer agent include Compound 2 represented by the following formula F2, Compound 3 represented by the following formula F3, alcohols (methanol, ethanol, etc.), chlorofluorocarbons (1,3-dichloro-1,1,2,2,3-pentafluoropropane, 1,1-dichloro-1-fluoroethane, etc.), hydrocarbons (pentane, hexane, cyclohexane, etc.), and mercaptans (tert-dodecyl mercaptan, n-octadecyl mercaptan, etc.). R 1 I2··· Formula F2 R 2 IBr··· Formula F3 In the formula F2, R 1 is an alkylene group or a polyfluoroalkylene group having 2 or more carbons. In the formula F3, R 2 is an alkylene group or a polyfluoroalkylene group having 1 to 16 carbons.

[0088] R 1 , R2 In the present application, the polyfluoroalkylene group can be linear or branched. As R 1 , R 2 , preferably a perfluoroalkylene group. As the compound 2, for example, 1,4-diiodoperfluorobutane, 1,2-diiodoperfluoroethane, 1,3-diiodoperfluoropropane, 1,5-diiodoperfluoropentane, 1,6-diiodoperfluorohexane can be exemplified. Among them, 1,4-diiodoperfluorobutane is preferred. As the compound 3, for example, 1-iodo-4-bromoperfluorobutane, 1-iodo-4-bromoperfluorobutane, 1-iodo-6-bromoperfluorohexane, 1-iodo-8-bromoperfluorooctane can be exemplified.

[0089] The iodine compound of the compound 2, the compound 3, or the like can function as a chain transfer agent. Therefore, if the respective monomers are copolymerized in the presence of the iodine compound, iodine atoms can be bonded to the ends of the main chain of the fluorine-containing elastomer (B2). In the case where a fluorine-containing elastomer (B2) having a branched chain is obtained, iodine atoms can also be incorporated at the ends of the branched chain.

[0090] As the polymerization method, for example, emulsion polymerization, solution polymerization, suspension polymerization, bulk polymerization, or the like can be exemplified. From the viewpoint of easiness in adjusting the number average molecular weight of the fluorine-containing elastomer (B2), the copolymer composition, and excellent productivity, the emulsion polymerization method in which the monomers are polymerized in the presence of an aqueous medium and an emulsifier is preferred. As the free radical chain initiator used in the emulsion polymerization, a water-soluble initiator is preferred. As the water-soluble initiator, for example, persulfate, hydrogen peroxide, a water-soluble organic peroxide, an organic initiator, a redox initiator composed of persulfate or hydrogen peroxide and a reducing agent, and an inorganic initiator in which the redox initiator further coexists with a small amount of iron, ferrous salt, silver sulfate, or the like can be exemplified. As the persulfate, for example, ammonium persulfate, sodium persulfate, potassium persulfate can be exemplified. As the water-soluble organic peroxide, for example, dibutylenesebacate peroxide, dipentylene glutarate peroxide, t-butyl hydroxy peroxide can be exemplified. As the organic initiator, for example, azobisdimethylamidinium dihydrochloride can be exemplified. As the reducing agent, for example, sodium bisulfite, sodium thiosulfate can be exemplified. In the emulsion polymerization method, the monomers are polymerized in the presence of an aqueous medium, an emulsifier, and a free radical polymerization initiator, and a latex of an elastomer is obtained. A pH adjustor can be used at the time of polymerization of the monomers.

[0091] The fluorine-containing elastomer (B2) preferably has iodine atoms. The content of the iodine atoms is preferably 0.05% by mass or more, more preferably 0.1 to 5% by mass, and further preferably 0.2 to 1% by mass, with respect to the total mass of the fluorine-containing elastomer (B2).

[0092] If the content of iodine atoms in the fluorine-containing elastomer (B2) is above the above lower limit value, iodine atoms bond with atoms on the surface of the flat conductor, and the adhesion of the insulating coating material to the flat conductor improves. As a result, the conformability of the insulating coating material film to the flat conductor improves at the time of bending deformation.

[0093] The amount of iodine atoms can also be controlled by controlling the type and amount of iodine atom-containing chain transfer agent, iodine atom-containing monomer, and reaction conditions.

[0094] <Other components> As the other components, for example, fluorine-containing polymers other than the fluorine-containing copolymer (B), non-fluorine-containing polymers other than the polyaryletherketone (A), fillers, pigments, other additives can be exemplified. As specific examples of the fillers, resins, inorganic fillers are preferable. As the resins, fibrous resins such as aramid fibers, liquid crystal polyester fibers, and the like, and powdered resins such as polytetrafluoroethylene in a powdered form, and the like can be exemplified. As the inorganic fillers, fibrous fillers such as glass fibers, carbon fibers, boron fibers, stainless steel microfibers, and the like, and powdered fillers such as talc, mica, graphite, molybdenum disulfide, calcium carbonate, silica, silica-alumina, alumina, titanium dioxide, and the like can be exemplified. Further, hydrotalcite and metal oxides such as zinc oxide, magnesium oxide, titanium oxide, lead oxide, copper oxide can be exemplified. Further, metal powders can also be used. For example, powders of stainless steel, iron-based materials, titanium, copper, nickel can be exemplified. The fillers can be used singly or in combination of two or more. As the pigments, coloring pigments such as organic pigments, inorganic pigments, and the like can be exemplified. As specific examples, carbon black (black pigment), iron oxide (red pigment), aluminum cobalt oxide (blue pigment), copper phthalocyanine (blue pigment, green pigment), perylene (red pigment), bismuth vanadate (yellow pigment) can be exemplified. The other components can be used singly or in combination of two or more.

[0095] <Manufacturing method of flat wire> The above flat wire can be manufactured by the following method: using an extruder provided with a die, melting a composition containing the polyaryletherketone (A) and the fluorine-containing copolymer (B), and extruding the melted composition from the die to the periphery of the flat conductor, thereby coating the melted composition around the flat conductor to form the insulating coating material. In the extruder, the above other components can be added in addition to the fluorine-containing copolymer.

[0096] (Composition) The composition contains the polyaryletherketone (A) and the fluorine-containing copolymer (B) having a unit based on tetrafluoroethylene. The composition can further contain other components than the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) as long as the properties thereof are not substantially impaired.

[0097] The total content of the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) is preferably 50% by mass or more, more preferably 70% by mass or more, and can be 100% by mass, with respect to the total mass of the composition.

[0098] The content of the fluorine-containing copolymer (B) is 5% by mass or more, preferably 5 to 45% by mass, and preferably 10 to 30% by mass, with respect to the total mass of the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) in the composition. That is, the content of the polyarylene ether ketone (A) is 95% by mass or less, preferably 55 to 95% by mass, and preferably 70 to 90% by mass, with respect to the total mass of the polyarylene ether ketone (A) and the fluorine-containing copolymer (B) in the composition.

[0099] The MFR of the composition at 372°C under a load of 49 N is preferably 19.0 to 300.0 g / 10 minutes, more preferably 25.0 to 250.0 g / 10 minutes, and further preferably 50.0 to 200.0 g / 10 minutes.

[0100] The weld strength of the composition is preferably 50 MPa or more, more preferably 60 MPa or more, and further preferably 70 MPa or more. If the weld strength is above the lower limit value described above, it is easy to obtain a flat wire in which the film of the insulating covering material has excellent compliance to the flat conductor at the time of bending deformation. The higher the weld strength, the better, and the upper limit value is not particularly limited. The upper limit value of the weld strength is, for example, 100 MPa. The weld strength of the composition is preferably 50 to 100 MPa, more preferably 60 to 100 MPa, and further preferably 70 to 100 MPa.

[0101] The heat expansion rate of the composition is preferably 0.48% or less, more preferably 0.45% or less, and further preferably 0.40% or less. If the heat expansion rate is below the upper limit value of the above numerical range, it is easy to obtain a flat wire in which the film of the insulating covering material has excellent compliance to the flat conductor at the time of bending deformation. The lower the heat expansion rate, the better, and the lower limit value is not particularly limited.

[0102] The Izod impact strength at 23°C when the composition is made into a test piece having a thickness of 4.0 mm is preferably 80 J / m or more, more preferably 90 J / m or more, and further preferably 100 J / m or more. If the Izod impact strength at 23°C is above the lower limit value described above, the impact resistance of the insulating covering material at ordinary temperature is excellent. The upper limit value of the Izod impact strength at 23°C is not particularly limited, and is, for example, NB (No break).

[0103] The molten (melt-kneaded) fluorine-containing copolymer (B) is preferably made into particles having a number average particle diameter of 0.5 to 10 μm and dispersed in the polyaryletherketone (A). By appropriately adjusting the melt-kneading temperature, the extrusion shear rate, and the residence time of the melt-kneading target in the melt-kneading device, the fluorine-containing copolymer (B) having a number average particle diameter of 0.5 to 10 μm can be dispersed in the polyaryletherketone (A).

[0104] (manufacturing conditions) As the extruder, a twin-screw extruder, a single-screw extruder, and preferably a twin-screw extruder can be exemplified. The opening surface of the die is rectangular in shape. The cylinder temperature and the die temperature of the extruder are set according to the kind of the polyaryletherketone (A) and the fluorine-containing copolymer (B). The cylinder temperature of the extruder is preferably 50 to 450°C, more preferably 80 to 440°C, and further preferably 90 to 430°C. The die temperature is preferably 100 to 420°C, more preferably 120 to 400°C, and further preferably 150 to 380°C. If the cylinder temperature and the die temperature of the extruder are above the above lower limit, the mixing of the materials is good. If the cylinder temperature and the die temperature of the extruder are below the above upper limit, the deterioration of the fluorine-containing copolymer (B) due to heat is easily suppressed. The residence time in the extruder is preferably 10 seconds or more and 30 minutes or less. The screw rotation speed of the extruder is preferably 0.5 to 100 rpm.

[0105] The flat conductor is preferably preheated. The temperature of the flat conductor after preheating is preferably 50 to 400°C, and more preferably 80 to 250°C. The preheating method is not particularly limited, and light heating, hot air heating, radiation heating, gas burner heating, induction heating, and the like can be exemplified.

[0106] (drawn ratio) In the manufacturing method of the flat wire of the present embodiment, the drawn ratio (hereinafter also referred to as "DDR") calculated from the following formula 1 is preferably 0.1 or more and less than 10.0, more preferably 0.5 or more and less than 10.0, further preferably 0.5 to 5, and particularly preferably 0.8 to 1.5. If the DDR is above the above lower limit, a flat wire in which the surface smoothness of the skin of the insulating coating material is excellent is easily obtained. If the DDR is less than the above upper limit (or below the above upper limit), a flat wire in which the surface smoothness of the skin of the insulating coating material and the compliance of the skin of the insulating coating material to the flat conductor at the time of bending deformation are excellent is easily obtained.

[0107] DDR = (D A - C A ) / (F A - C A) Formula 1 In the above Formula 1, D A is the opening area of the die (mm 2 ), C A is the area of the cross section of the flat conductor in the direction perpendicular to the axial direction (mm 2 ), and F A is the area of the cross section of the flat wire in the direction perpendicular to the axial direction (mm 2 ).

[0108] D A may be obtained from the following Formula 2. D A = D L x D S Formula 2 In the above Formula 2, D L is the length of the inner dimension of the long side of the rectangular opening surface of the die (mm), and D S is the length of the inner dimension of the short side of the rectangular opening surface of the die (mm).

[0109] C A may be obtained from the following Formula 3. C A = C L x C S Formula 3 In the above Formula 3, C L is the length of the long side of the rectangular cross section of the flat conductor in the direction perpendicular to the axial direction (mm), and C S is the length of the short side of the rectangular cross section of the flat conductor in the direction perpendicular to the axial direction (mm).

[0110] F A may be obtained from the following Formula 4. F A = F L x F S Formula 4 In the above Formula 4, F L is the length of the long side of the rectangular cross section of the flat wire in the direction perpendicular to the axial direction (mm), and F S is the length of the short side of the rectangular cross section of the flat wire in the direction perpendicular to the axial direction (mm).

[0111] In the present embodiment, it is preferable that the formation of the insulating coating material be performed under pressure, i.e., it is preferable that a so-called press forming method be employed. By employing the press forming method, the DDR is easily made smaller than the above upper limit value (or below the above upper limit value) compared to the conventional tube forming method, and as a result, a flat wire in which the surface smoothness of the film of the insulating coating material and the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation are excellent is easily obtained.

[0112] (Use) The flat wire of the present application can be applied to, for example, an isolated amplifier, an isolated transformer, an alternator of an automobile, a hybrid automobile, an electric ship, an electric airplane, an electric vertical takeoff and landing airplane, and the like. In addition, it can also be used as various electric wires (winding electric wires, automobile electric wires, robot electric wires), coil windings (electromagnetic wires). Examples

[0113] The present application is described in more detail below using examples, but the present application is not limited to these examples. In the following examples, Examples 1 to 10 are examples, and Examples 11 to 24 are comparative examples.

[0114] <Method of Evaluation> (MFR of the Insulating Coating Material) The MFR under 49N was measured according to JIS K 7210-1:2014 after preheating the insulating coating material at 372°C for 5 minutes. The measurement was performed at 372°C. In addition, in the case where the MFR is greater than 100 g / 10 minutes, the preheating time can also be 30 seconds to 180 seconds.

[0115] (MFR of the Polyaryletherketone (A) and Fluorine-Containing Resin (B1)) The MFR under 49N was measured according to JIS K 7210-1:2014. The measurement was performed at 372°C.

[0116] (MFR of the Fluorine-Containing Elastomer (B2)) The MFR under 21N was measured according to JIS K 7210-1:2014. The measurement was performed at 230°C.

[0117] (Melt Viscosity of the Polyaryletherketone (A) and Fluorine-Containing Copolymer (B)) The melt viscosity was measured using a capillary rheometer (manufactured by Toyo Rikiki Co., Ltd., capillary length L: 10 mm, capillary inner diameter r: 1.0 mm, piston diameter D: 9.55 mm). For the polyaryletherketone (A) and the fluorine-containing resin (B1), the measurement was performed at a temperature: 390°C, a shear rate: 122 sec -1 For the fluorine-containing elastomer (B2), the measurement was performed at a temperature: 300°C, a shear rate: 122 sec -1 For the fluorine-containing elastomer (B2), the measurement was performed at a temperature: 300°C, a shear rate: 122 sec

[0118] (Melting Point of the Polyaryletherketone (A) and Fluorine-Containing Resin (B1)) The melting peak when the polyaryletherketone (A) or the fluorine-containing resin (B1) was warmed at a rate of 10°C / minute was recorded using a differential scanning calorimeter (manufactured by Seiko Instruments Inc.), and the temperature corresponding to the maximum value was the melting point.

[0119] (Mooney Viscosity (ML1+10 , 121°C) Determined using a SMV-201 (manufactured by Shimadzu Corporation) in accordance with JIS K6300-1:2000 (corresponding to international standards ISO 289-1:2005, ISO 289-2:1994) at 121°C.

[0120] Storage modulus G' of fluoroelastomer (B2) Determined using an RPA2000 (manufactured by Alpha Technologies) in accordance with ASTM D6204 at 100°C at 50 cpm.

[0121] Content of -CH2OH group of fluoroelastomer (B2) The particles of fluoroelastomer (B2) were molded by cold press molding to produce a film having a thickness of 0.25 to 0.30 mm. This film was scanned 40 times with a Fourier transform infrared spectrometer (FT-IR (Spectrum One, manufactured by PerkinElmer)) and analyzed to obtain infrared absorption spectrum 1. The same operation was performed on particles of fluoroelastomer having no -CH2OH group (where the thickness of the film was the same) to obtain infrared absorption spectrum 2. Infrared absorption spectrum 1 was subtracted from infrared absorption spectrum 2 to obtain a difference spectrum. From the peak (absorbance) at 3648 cm -1 of the difference spectrum, the content of -CH2OH group relative to 1 x 10 6 carbon atoms of the main chain of fluoroelastomer (B2) was calculated from the following formula 5. The peak at 3648 cm -1 was confirmed in the model compound C7H 15 CH2OH having a -CH2OH group. In addition, the molar absorption coefficient of -CH2OH group was 104 (absorbance / cm / mol). N = I x A x t Formula 5 In the above formula 5, I is absorbance, A is a correction coefficient, which is 2236 for -CH2OH group, and t is the thickness of the film (mm).

[0122] Iodine content of fluoroelastomer (B2) The iodine content of fluoroelastomer (B2) was determined using an ion chromatography measuring device (device in which an automatic sample combustion device ion chromatography pretreatment device AQF-100 type is combined with an ion chromatograph, manufactured by Dia Instruments Corporation).

[0123] Welding strength of composition The composition comprising the particulate polyarylene ether ketone (A) and the fluorine-containing copolymer (B) was pre-dried at 200°C for 3 hours under heating. Thereafter, the composition was injection-molded using an injection molding machine (ROBOSHOT α-50 manufactured by Fanuc Corporation) and a mold for measuring the weld strength under the conditions of a cylinder temperature: 380°C and a mold temperature: 170°C, to obtain a test piece in conformity with ISO 527, Sample Size: IB. The test piece was measured in accordance with ISO 527 using a Tensilon universal testing machine RTF-1350 (manufactured by Ander Co., Ltd.).

[0124] (Heat expansion rate of the composition) The composition was molded into a sheet having a thickness of 0.5 mm using a hot press machine manufactured by TESTER Sangyo Co., Ltd. under the conditions of a processing temperature of 370°C, preheating for 10 minutes, a pressure of 10 MPa, and a pressurization time of 3 minutes. A square sample having a size of 4 mm x 4 mm x thickness 0.5 mm was cut out from the obtained sheet. The obtained sample was measured for a TMA curve (abscissa: temperature, ordinate: deformation amount) using a TMA device (TMA / SS6100 manufactured by Hitachi High-Technologies Corporation) in accordance with JIS K7196:1991 (measurement mode: needle insertion mode) under the conditions of a temperature setting: 30 to 390°C, a temperature increase rate: 5°C / minute, and a load: 100 mN. In the temperature range of 50 to 303°C of the obtained TMA curve, the maximum dimensional change rate at which the value of the deformation amount changes the most was found, which was the heat expansion rate. The dimensional change rate was specifically calculated by the following equation. Dimensional change rate (%) = (thickness direction length after test - thickness direction length before test) / thickness direction length before test x 100

[0125] (Preparation of the evaluation injection-molded body) The composition comprising the particulate polyarylene ether ketone (A) and the fluorine-containing copolymer (B) was pre-dried at 200°C for 3 hours under heating. Thereafter, the composition was injection-molded using an injection molding machine (ROBOSHOT α-50 manufactured by Fanuc Corporation) under the conditions of a cylinder temperature: 380°C and a mold temperature: 170°C, to obtain an evaluation injection-molded body having a thickness: 4.0 mm.

[0126] (Chisel impact strength of the composition) A test piece having a length: 80 mm and a width: 10 mm was cut out from the evaluation injection-molded body, and a notch was cut at a position of a height: 40 mm of the test piece. For the test piece, the Izod impact strength was measured using an Izod impact tester (manufactured by Toyo Seiki Jiki Kogyo Co., Ltd.) under the following conditions: hammer capacity: 2.75 J, hammer load: 13.97 N, distance from the axis to the center of gravity: 10.54 cm, distance from the axis to the point of impact: 33.5 cm. The measurement was performed at 23°C.

[0127] (Number average particle diameter of fluorine-containing copolymer (B) in the composition) For the evaluation injection-molded body, observation was performed using a scanning electron microscope (manufactured by Hitachi, Ltd., S-4800), the maximum diameter of 100 particles selected at random was measured, the arithmetic mean was calculated, and the number average particle diameter of the fluorine-containing copolymer (B) in the composition was calculated.

[0128] (Local discharge inception voltage of the insulation coating material) The skin of the insulation coating material was cut out from the flat conductor of the flat wire, and pressure molding was performed (350°C, preheating for 5 minutes, pressure for 2 minutes) to obtain a measurement sample of 130 mm x 130 mm x 0.12 mm in thickness. Using the obtained measurement sample, the local discharge inception voltage of the insulation coating material was measured under the following measurement conditions (low frequency method). The voltage at which 10 pC of discharge charge was detected was taken as the local discharge inception voltage. In addition, the measurement was performed on five measurement samples, and the average of them was taken as the local discharge inception voltage. In Tables 1 to 3, the local discharge inception voltage is denoted as PDIV. [Measurement conditions] Measurement device: Partial Discharge Detector A-006, manufactured by Fujikura Dia Cable Co., Ltd. Electrode: An electrode conforming to JIS C 2110-1 was used. Test voltage: Set to a maximum of 20 kVrms (50 Hz), and the voltage was decreased after 100 pC of discharge charge was detected. Voltage rise and fall speed: 100 V / sec. Other conditions: In the atmosphere, temperature: 18 degrees, relative humidity: 30%.

[0129] (Average thickness and thickness variation of the skin) Five meters of the flat wire were taken, and the thickness of the skin of the insulation coating material on the long side in the rectangular cross section perpendicular to the axial direction (only the side that contacted the upper inner surface of the die during molding) was measured at every 100 mm. The arithmetic mean of the measurement values (mm) was taken as the average thickness. The unbiased standard deviation (mm) of the measurement values (mm) was taken as the thickness variation.

[0130] (Winding test) The flat wire was evaluated by a winding test in accordance with "JIS 3216-3:2011 5.1.2 Flat wire". The cross section of the flat wire was confirmed by visual observation, and evaluated according to the following criteria. A: The film of the insulating coating material was peeled off from the flat conductor. B: The film of the insulating coating material was peeled off from the flat conductor.

[0131] (Compliance) For the flat wire, bending deformation in the edgewise and flatwise directions was performed, respectively. The deformation angle was 90 ± 10°. Thereafter, the surface of the film of the insulating coating material and the cross section of the flat wire of the portion after the bending deformation were observed by visual observation, and the compliance was evaluated according to the following criteria. A: No wrinkle was generated on the surface of the film of the insulating coating material at the time of the above bending, and no phenomenon of peeling of the film of the insulating coating material from the flat conductor occurred. B: A wrinkle was generated on the surface of the film of the insulating coating material at the time of the above bending, or a phenomenon of peeling of the film of the insulating coating material from the flat conductor occurred.

[0132] (Surface smoothness) For the flat wire, the surface roughness (Ra) was measured with a digital microscope (manufactured by HORIX Co., Ltd., HRX-1). The measurement was performed at a magnification of 80 times and a measurement length of 4 mm. A: The surface roughness was 45 μm or less B: The surface roughness was more than 45 μm

[0133] <Usage materials> (Polyaryletherketone (A)) • Polyaryletherketone (Al): PEEK (manufactured by SABIC Innovative Plastics, product name "VESTAKEEP 2000G", melting point: 340°C, MFR: 64 g / 10 minutes, melt viscosity: 290 Pa-s, specific gravity: 1.32). • Polyaryletherketone (A2): PEEK (manufactured by SABIC Innovative Plastics, product name "VESTAKEEP 1000G", melting point: 340°C, MFR: 140 g / 10 minutes, melt viscosity: 178 Pa-s, specific gravity: 1.32). • Polyaryletherketone (A3): PEEK (manufactured by SABIC Innovative Plastics, product name "VESTAKEEP 3300G", melting point: 340°C, MFR: 21 g / 10 minutes, melt viscosity: 700 Pa / s, specific gravity: 1.32).

[0134] Fluorine-containing copolymer (B) Fluoropolymer (B1): A fluoropolymer with a molar ratio of TFE units:PPVE units:NAH units = 97.9:2.0:0.1 (melting point: 300℃, specific gravity: 2.13, MFR: 16g / 10min, melt viscosity: 1120Pa·s, relative to the number of carbon atoms in the main chain 1×10). 6 The content of -CH2OH groups: 303. Fluorinated elastomer (B2-1): A fluorinated elastomer with a molar ratio of TFE units:P units = 56:44 and containing 0.4% by mass of iodine atoms relative to the mass of the fluorinated elastomer; MFR: difficult to determine (<150 g / 10 min); melt viscosity: <300 Pa·s; specific gravity: 1.55; Mooney viscosity (ML). 1+10 (121℃): 50, energy storage modulus G': 250kPa). Fluorinated elastomer (B2-2): A fluorinated elastomer with a molar ratio of TFE units to P units of 56:44 and lacking iodine atoms; MFR: 11 g / 10 min; melt viscosity: 270 Pa·s; specific gravity: 1.55; Mooney viscosity (ML). 1+10 (121℃): 100, energy storage modulus G': 390kPa).

[0135] (Example 1) The compositions of the formulations listed in Table 1 are subjected to wire extrusion molding under the following conditions to produce flat wires. DDR is 1. In wire extrusion molding, the insulating coating material is formed under pressure, i.e., a so-called pressure molding method is employed. Die head temperature: 390℃. Barrel temperature: 320~390℃. Flat conductor: Flat copper wire, 1.473mm thick and 2.278mm wide. Preheating temperature for flat conductors: 180℃. Coating thickness (set value): 0.12mm.

[0136] (Examples 2~24) In addition to using the compositions formulated in Tables 1-3, flat wires were manufactured in the same manner as in Example 1. In Examples 11-24, the DDR was 15, and the insulating coating material was formed essentially under normal pressure, i.e., using the so-called tube forming method.

[0137] The insulation coating materials and flat wires of each example were evaluated as described above. The results are shown in Tables 1-3.

[0138] [Table 1]

[0139] [Table 2]

[0140] [Table 3]

[0141] In Examples 1 to 10, the surface smoothness of the film of the insulating coating material and the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation were excellent. In Examples 11 and 12 not containing the fluorine-containing copolymer (B), the surface smoothness of the film of the insulating coating material and the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation were poor. In Examples 13 to 16 in which the MFR of the insulating coating material under a load of 49 N at 372°C was less than 20.0 g / 10 minutes, the surface smoothness of the film of the insulating coating material and the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation were poor. In Examples 17 to 24 containing the fluorine-containing copolymer (B), in which the MFR of the insulating coating material under a load of 49 N at 372°C was 20.0 to 300.0 g / 10 minutes and the DDR was 15, the surface smoothness of the film of the insulating coating material and the compliance of the film of the insulating coating material to the flat conductor at the time of bending deformation were poor.

Claims

1. A flat wire comprising a flat conductor having a rectangular cross-section in a direction perpendicular to the axial direction, and a film of an insulating coating material formed by extrusion directly covering the entire circumference of the flat conductor, wherein, The melt flow rate of the insulating coating material at a temperature of 372℃ and a load of 49N is 20.0–300.0 g / 10 min, the average thickness of the film of the insulating coating material is 10–1000 μm, and the unbiased standard deviation of the thickness of the film of the insulating coating material along the axial direction of the flat wire is less than 0.06 mm. The insulating coating material comprises polyaryletherketone (A) and a fluorinated copolymer (B) having tetrafluoroethylene-based units, wherein the fluorinated copolymer (B) comprises one or more selected from fluorinated resins (B1) and fluorinated elastomers (B2) with melting points above 260°C, and the content of the fluorinated copolymer (B) is 5% by mass or more relative to the total mass of the polyaryletherketone (A) and the fluorinated copolymer (B) in the insulating coating material. In the winding test according to "JIS3216-3:2011-5.1.2 Flat Wire", the film of the insulating coating material does not peel off from the flat conductor.

2. The flat line as described in claim 1, wherein, The cross-sectional area of ​​the flat conductor is 2.6 mm². 2 above.

3. The flat line as described in claim 1 or 2, wherein, The fluorinated resin (B1) has -CH2OH groups, and the content of the -CH2OH groups is 1 × 10⁻⁶ carbons in the main chain of the fluorinated resin (B1). 6 More than 30.

4. The flat line as described in claim 1 or 2, wherein, The fluorinated elastomer (B2) has iodine atoms, and the content of the iodine atoms is more than 0.05% by mass relative to the total mass of the fluorinated elastomer (B2).

5. The flat line as described in claim 1 or 2, wherein, The partial discharge initiation voltage of the insulating coating material is above 600Vrms.

6. A method for manufacturing a flat wire, comprising a flat conductor having a rectangular cross-section in a direction perpendicular to the axial direction, and a film of insulating coating material formed by extrusion directly covering the entire circumference of the flat conductor, the method comprising the following steps: Using an extruder equipped with a die, a composition comprising polyaryletherketone (A) and a fluorinated copolymer (B) having tetrafluoroethylene-based units is melted, and the molten composition is extruded from the die around the flat conductor, thereby coating the flat conductor with the molten composition to form the insulating coating material. The melt flow rate of the insulating coating material at a temperature of 372℃ and a load of 49N is 20.0–300.0 g / 10 min, the average thickness of the film of the insulating coating material is 10–1000 μm, and the unbiased standard deviation of the thickness of the film of the insulating coating material along the axial direction of the flat wire is less than 0.06 mm. The fluorinated copolymer (B) comprises one or more selected from fluorinated resins (B1) and fluorinated elastomers (B2) with melting points above 260°C, and the content of the fluorinated copolymer (B) is 5% by mass or more relative to the total mass of the polyarylether ketone (A) and the fluorinated copolymer (B) in the composition. In the winding test according to "JIS3216-3:2011-5.1.2 Flat Wire", the film of the insulating coating material does not peel off from the flat conductor.

7. The method for manufacturing a flat wire as described in claim 6, wherein, The stretching ratio DDR calculated by Formula 1 is above 0.5 and less than 10.

0. DDR = (D A - C A ) / (F A - C A ) Formula 1 In Equation 1, D A The opening area of ​​the die head (mm²) 2 ), C A The area (mm²) of the cross-section of the flat conductor in the direction perpendicular to the axial direction. 2 ), F A The area (mm²) of the cross section of the flat line in the direction perpendicular to the axial direction. 2 ).

8. The method for manufacturing a flat wire as described in claim 6 or 7, wherein, The cross-sectional area of ​​the flat conductor is 2.6 mm². 2 above.

9. The method for manufacturing a flat wire as described in claim 6 or 7, wherein, The fluorinated resin (B1) has -CH2OH groups, and the content of the -CH2OH groups is 1 × 10⁻⁶ carbons in the main chain of the fluorinated resin (B1). 6 More than 30.

10. The method for manufacturing a flat wire as described in claim 6 or 7, wherein, The fluorinated elastomer (B2) has iodine atoms, and the content of the iodine atoms is more than 0.05% by mass relative to the total mass of the fluorinated elastomer (B2).

11. The method for manufacturing a flat wire as described in claim 6 or 7, wherein, The partial discharge initiation voltage of the insulating coating material is above 600Vrms.

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